Total Results: 14105
Mechanical Behaviour of an Aluminium Alloy With Fusible Grain Boundaries
92
Authors: B. Baudelet; M. C. Dang; F. Bordeaux; INSTITUT NATIONAL POLYTECHNIQUE DE GRENOBLE (FRANCE)
7000 SERIES Al alloy was shown to have a liquid grain boundary, the extent and distribution of which depended on the thermal history of the material. If T was less than 477 C (melting temperature of the boundary), the solid material displayed classical mechanical behavior. At T greater than 477 C, it was observed that the liquid grain boundary influenced the mechanical behavior of the alloy. At higher strain rates ...
Creep Fracture Mechanisms in Single Crystal Superalloys
92
Authors: S. H. Ai; V. Lupinc; M. Maldini; ACADEMIA SINICA SHENYANG (CHINA) INST OF METAL RESEARCH
Using constant load creep tests, the creep fracture mechanisms of single crystal superalloys CMSX-2, SRR 99 and RR 2000 were studied. Crystals having orientations within 12 degrees of were tested in air between 750- 1000 C. It was shown that creep cracks always initiated at carbides in alloys containing a higher carbon level and at casting pores. Crack propagation occurred anisotropically along the crystallographic planes perpendicular to the applied load ...
High Temperature Tensile Deformation of a Nitrided Fe-1%V Alloy
92
Authors: A. Sakir Bor; MIDDLE EAST TECHNICAL UNIV ANKARA (TURKEY) DEPT OF METALLURGICAL ENGINEERING
A nominally pure Fe-1V alloy with less than 0.01% total impurities, and with homogeneously distributed vanadium nitride precipitates which had been formed by gas nitriding, was used to determine the relations governing the hot tensile deformation behavior. The true stress-strain at various temperatures from 673 to 1073K and strain rates 10-2 to 10-4/s for the alloys are reported. Temperature and strain rate dependence of the strength coefficient, K, obeyed an ...
Superplastic Behavior at High Strain Rates of a Mechanically Alloyed Al- Mg-Li Alloy
92
Authors: K. Higashi; T. Okada; T. Mukai; S. Tanimura; OSAKA PREFECTURE UNIV SAKAI (JAPAN) DEPT OF MECHANICAL ENGINEERING
The possible mechanisms of high strain rate superplasticity were analyzed by studying the tensile behavior of thin rolled sheet specimens of mechanically alloyed IN905XL with ultrafine grained structure (400nm in mean size) at various strain rates and temperatures. Strain rate sensitivity increased from 0.3 to 0.5 with increasing temperature.
articles
Wednesday, April 29, 2009
Atomic Absorption Spectrophotometer AAS –21
[PDF] Atomic Absorption Spectrophotometer AAS –21 - [ Terjemahkan laman ini ]
Jenis Berkas: PDF/Adobe Acrobat - Versi HTML
FEATURES:
Innovated rich oxygen air-acetylene flame analysis technique:
The patented flame analysis technique adopting rich oxygen air-acetylene flame as the substitution for nitrous oxide-acetylene flame for high temperature element analyses, such as Ca, Al, Ba, W, Mo, Ti, V, etc. Flame temperature is continuously adjustable between 2300-2950 with makes it possible to choose the best atomization temperature for different elements. It features easy operation, low analysis cost and wide flame AAS analytical range. Rich oxygen flame will not pollute the environment and is not harmful to human bodies. It's break-through in flame AAS analysis Integrated flame/graphite furnace atomization system, changeable with flame emission burner;
• Automatically controlled changeover of the integrated flame and graphite furnace atomizer
featuring easy operation and time saving eliminates human labor
• A flame emission burner head can be installed to perform flame emission analysis to akali
metais as K, Na etc.
Accurate fully automated control system
• Automatic 6-lamp turret, automatic adjustment of lamp current and optimization of light beam
position
• Automatic wavelength scanning and peak picking
• Automatic spectral bandwidth changing
• Automatic changeover between flame and graphite furnace operation, automatic optimization
of position parameters, automatic ignition and automatic gas flow setting
Jenis Berkas: PDF/Adobe Acrobat - Versi HTML
FEATURES:
Innovated rich oxygen air-acetylene flame analysis technique:
The patented flame analysis technique adopting rich oxygen air-acetylene flame as the substitution for nitrous oxide-acetylene flame for high temperature element analyses, such as Ca, Al, Ba, W, Mo, Ti, V, etc. Flame temperature is continuously adjustable between 2300-2950 with makes it possible to choose the best atomization temperature for different elements. It features easy operation, low analysis cost and wide flame AAS analytical range. Rich oxygen flame will not pollute the environment and is not harmful to human bodies. It's break-through in flame AAS analysis Integrated flame/graphite furnace atomization system, changeable with flame emission burner;
• Automatically controlled changeover of the integrated flame and graphite furnace atomizer
featuring easy operation and time saving eliminates human labor
• A flame emission burner head can be installed to perform flame emission analysis to akali
metais as K, Na etc.
Accurate fully automated control system
• Automatic 6-lamp turret, automatic adjustment of lamp current and optimization of light beam
position
• Automatic wavelength scanning and peak picking
• Automatic spectral bandwidth changing
• Automatic changeover between flame and graphite furnace operation, automatic optimization
of position parameters, automatic ignition and automatic gas flow setting
Saturday, April 18, 2009
Baseline geochemical data for stream sediment and surface water
[PDF] Baseline analytical data for stream sediment and surface water ... - [ Terjemahkan laman ini ]
Jenis Berkas: PDF/Adobe Acrobat - Versi HTMLspectrophotometry following the method of O'Leary and Meier (1996). ... Co, Cr, Cu, Fe, Ga, Ge, La, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Pd, Pt, Sb, Sc, Sn, Sr, Th, Ti, V, W,. Y, Zn, and Zr. This method is designated ES in Table 2 and in the data ... This is particularly true for the major elements Al, Ca, Fe, K, Mg, ...
Jenis Berkas: PDF/Adobe Acrobat - Versi HTMLspectrophotometry following the method of O'Leary and Meier (1996). ... Co, Cr, Cu, Fe, Ga, Ge, La, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Pd, Pt, Sb, Sc, Sn, Sr, Th, Ti, V, W,. Y, Zn, and Zr. This method is designated ES in Table 2 and in the data ... This is particularly true for the major elements Al, Ca, Fe, K, Mg, ...
INTRODUCTION
During a 3-week period in the summer of 1996, the U.S. Geological Survey conducted a reconnaissance baseline geochemical study in central Idaho. Areas covered include Panther Creek, the Middle Fork of the Salmon River from Boundary Creek to the mouth, and the Main
Salmon River from North Fork to Corn Creek (Fig. 1). Stream sediment samples were collected
at all sample sites. Filtered and unfiltered stream water samples were collected at most sample
sites. The purpose of the baseline study was to establish a “geochemical snapshot” of the area,
as a datum for monitoring future change in the geochemical landscape, whether natural or human-induced. Events that could change the geochemical landscape include, but are not limited to, mining, flood, landslide, wildfire, or resource extraction activities. In the summer of 2000, there were numerous large wildfires in central Idaho. In particular, the Clear Creek (206,000 acres; 83,370 hectares), Little Pistol (74,000 acres; 29,950 hectares), and Shellrock (64,000 acres; 25,900 hectares) fires swept across much of the area that was sampled. Thus, these data represent a pre-fire baseline geochemical dataset. A 2001 post-fire study is planned and will involve re-sampling of the pre-fire baseline sites, to allow for pre- and post-fire comparison. Sampling was conducted from July 8-28, 1996. Weather during this period was warm and precipitation sparse. Only one rain event occurred during the sampling period—a brief rain storm on the evening of July 16, with about ¼” (0.64 cm) of total precipitation. River levels were lower than normal for this time of year because of lower-than-normal precipitation during
the previous winter and spring. The study area lies within the Salmon River Mountains, and much of the area— particularly along the Middle Fork of the Salmon River—lies within the Frank Church-River of No Return Wilderness (Fig. 1). Topographic relief is high. Peaks at the heads of drainages commonly have elevations above 9000 ft (2740 m), while river-level elevations are typically several thousand feet lower, ranging from around 5700 ft (1740 m) at Boundary Creek on the Middle Fork of the Salmon River, to less than 3000 ft (914 m) at Corn Creek on the Main
Salmon River. Terrain ranges from rugged, steep peaks, ridges, and cirques at higher elevations,
through tree-covered mountains and meadows at intermediate elevations, to steep, narrow, heavily vegetated canyons at lower elevations. Climatic conditions vary from warm summer days with frequent thunderstorms to cold winter days with heavy snowfall accumulations. Access to the Panther Creek basin is by U.S. Forest Service gravel roads 030 from North Fork, Idaho, and 055, which runs along Panther Creek. Access to the Main Salmon River from North Fork to Corn Creek is by U.S. Highway 93 and U.S. Forest Service gravel road 030, which runs along the Main Salmon, ending at Corn Creek, and by raft or jet boat. Access to the Middle Fork of the Salmon River is exclusively by oar-powered raft or pack trail.
OVERVIEW OF ENVIRONMENTAL ANALYSIS
A. INTRODUCTION
1. Environmental Analysis
Environmental analysis, as used in these notes, is the chemical (or physical) characterization of some component of the natural or engineered environment. One may speak of four facets to environmental analysis:
1. Analytical Methods
2. Sampling Protocol
3. Quality Control
4. Data Analysis
The first, analytical methods, is what one most commonly associates with chemical analysis of the environment. It is the recipe or set of laboratory procedures one follows in order to obtain a signal that can be related to the concentration of the analyte. Analytical methods are presented in Chapters XV-XXII, and grouped according to the instrument or apparatus used. The second facet, sampling protocol, is sometimes trivial, yet sometimes very important and complex. Sampling is the means by which a subset of the environmental matrix of interest is selected, stored and transported to the laboratory for analysis (Chapter XIII). Then, quality control, is a set of procedures which are intended to warn the analyst when his/her analytical method is not working properly (Chapter XII). Some of these procedures may be implicitly writted into the analytical method. Finally, data analysis, is required to place the analytical results into the framework of a numerical value with uncertainty. Statistical theory plays an important role in this process, and this subject is treated in Chapter XXIII.
2. Analytical Methods
supplemental Material and Method
[PDF] Figure Legends - [ Terjemahkan laman ini ]
Jenis Berkas: PDF/Adobe Acrobat
Aliquots were then analyzed for Ag, Al, As, Ba, Be, Ca, Cd, Co,. Cr, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sr, Te, Ti, V, Y, Zn, and Zr ...
Supplemental Materials and Methods
SWCNT particles
Commercially manufactured raw SWCNT made by the Arc method in specifically designed chambers was obtained through collaboration with the National Institute of Standards and Technology (NIST, Gaithersburg, MD. The SE grade SWCNT manufactured by CarboLex was reported to have a purity of 70-90% and contained catalyst impurities encapsulated in carbon shells (Carbolex Inc., Broomall, PA). Some amorphous carbon was also found on the outer surfaces of the ropes. The SWCNT were heated by the manufacturer to 2,800° C in an argon atmosphere using a graphite furnace to improve structural integrity and to remove polyaromatic hydrocarbons and a significant amount of iron. The individual SWCNT are self-assembled into a rope bundle structure. SWCNT manufactured by this method are reported to have an average diameter of 1.4 nm with lengths of 2-5 μm.
Jenis Berkas: PDF/Adobe Acrobat
Aliquots were then analyzed for Ag, Al, As, Ba, Be, Ca, Cd, Co,. Cr, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sr, Te, Ti, V, Y, Zn, and Zr ...
Supplemental Materials and Methods
SWCNT particles
Commercially manufactured raw SWCNT made by the Arc method in specifically designed chambers was obtained through collaboration with the National Institute of Standards and Technology (NIST, Gaithersburg, MD. The SE grade SWCNT manufactured by CarboLex was reported to have a purity of 70-90% and contained catalyst impurities encapsulated in carbon shells (Carbolex Inc., Broomall, PA). Some amorphous carbon was also found on the outer surfaces of the ropes. The SWCNT were heated by the manufacturer to 2,800° C in an argon atmosphere using a graphite furnace to improve structural integrity and to remove polyaromatic hydrocarbons and a significant amount of iron. The individual SWCNT are self-assembled into a rope bundle structure. SWCNT manufactured by this method are reported to have an average diameter of 1.4 nm with lengths of 2-5 μm.
Monday, April 6, 2009
GMELIN, Handbook of Inorganic and Organometallic Chemistry
[PDF] Section 4: Compounds (Continued) - [ Terjemahkan laman ini ]Jenis Berkas: PDF/Adobe Acrobat
system, or Mn, Fe, Co, Ni, as well as a nonmetal element. Concludes the series on the purely ...... compounds, as well as detection and determination, conclude the ..... Ca, Mg, B, Al, Ga, In, Tl, Si, Ge, Sn, and Pb. Contains the formula ...... covered contain Sb, Bi, Zn, Hg, Al, Ti, Zr, Hf, Th, Sn, Pb, V, Ta, Cr, ...
ublib.buffalo.edu/libraries/asl/guides/Gmelin-Complete-Catalog.pdf - Halaman sejenis
system, or Mn, Fe, Co, Ni, as well as a nonmetal element. Concludes the series on the purely ...... compounds, as well as detection and determination, conclude the ..... Ca, Mg, B, Al, Ga, In, Tl, Si, Ge, Sn, and Pb. Contains the formula ...... covered contain Sb, Bi, Zn, Hg, Al, Ti, Zr, Hf, Th, Sn, Pb, V, Ta, Cr, ...
ublib.buffalo.edu/libraries/asl/guides/Gmelin-Complete-Catalog.pdf - Halaman sejenis
Sunday, March 8, 2009
OVERVIEW OF ENVIRONMENTAL ANALYSIS
A. INTRODUCTION
1. Environmental Analysis
Environmental analysis, as used in these notes, is the chemical (or physical) characterization of some component of the natural or engineered environment. One may speak of four facets to environmental analysis:
1. Analytical Methods
2. Sampling Protocol
3. Quality Control
4. Data Analysis
B. TRADITIONAL CLASSIFICATION OF ANALYTICAL METHODS
I. Classical
A. Gravimetric
1. Evaporation
2. Filtration
3. Precipitation
4. Extraction
B. Volumetric Analysis or Titrimetric Analysis
1. Acid/Base
2. Precipitation
3. Complexation or Chelation
4. Oxidation/Reduction
II. Modern or Instrumental Methods
A. Spectroscopic Methods
1. Molecular
a. Molecular Absorption
i. Ultraviolet/Visible
ii. Infrared
b. Molecular Emission
2. Atomic
b. Atomic Absorption (AAS)
i. Flame
ii. Furnace
b. Atomic Emission
i. Flame
ii. Plasma
B. Electrochemical Methods
1. Potentiometry
a. Glass Electrode
b. Ion Selective Electrodes (ISE)
2. Amperometry
3. Voltammetry
4. Conductance
C. Chromatographic Methods
1. Planar Chromatography
2. Gas Chromatography
a. Flame Ionization Detection
b. Electron Capture Detection
c. Thermal Conductivity
3. Liquid Chromatography
D. Mass Spectrometry
a. Probe Introduction
b. GC Introduction (GC/MS)
c. LC Introduction (LC/MS)
E. Nuclear Methods
III. Biochemical Methods
A. Whole Organisms
B. Cell Cultures
C. Enzyme Systems
Articles
1. Environmental Analysis
Environmental analysis, as used in these notes, is the chemical (or physical) characterization of some component of the natural or engineered environment. One may speak of four facets to environmental analysis:
1. Analytical Methods
2. Sampling Protocol
3. Quality Control
4. Data Analysis
B. TRADITIONAL CLASSIFICATION OF ANALYTICAL METHODS
I. Classical
A. Gravimetric
1. Evaporation
2. Filtration
3. Precipitation
4. Extraction
B. Volumetric Analysis or Titrimetric Analysis
1. Acid/Base
2. Precipitation
3. Complexation or Chelation
4. Oxidation/Reduction
II. Modern or Instrumental Methods
A. Spectroscopic Methods
1. Molecular
a. Molecular Absorption
i. Ultraviolet/Visible
ii. Infrared
b. Molecular Emission
2. Atomic
b. Atomic Absorption (AAS)
i. Flame
ii. Furnace
b. Atomic Emission
i. Flame
ii. Plasma
B. Electrochemical Methods
1. Potentiometry
a. Glass Electrode
b. Ion Selective Electrodes (ISE)
2. Amperometry
3. Voltammetry
4. Conductance
C. Chromatographic Methods
1. Planar Chromatography
2. Gas Chromatography
a. Flame Ionization Detection
b. Electron Capture Detection
c. Thermal Conductivity
3. Liquid Chromatography
D. Mass Spectrometry
a. Probe Introduction
b. GC Introduction (GC/MS)
c. LC Introduction (LC/MS)
E. Nuclear Methods
III. Biochemical Methods
A. Whole Organisms
B. Cell Cultures
C. Enzyme Systems
Articles
Saturday, March 7, 2009
12th General Conference of the Romanian Physical Society "TRENDS IN PHYSICS"
FOREWORD
The Romanian Physical Society (RPS) has been organizing, every year, the National Conference of Physics, since 1990, the date of society's post-war initiation. It however continues a tradition that the community of physicists managed to pursue for two decades earlier. There are important differences as comparing with the past in many respects: logistics, means, motivation of participation both of institutions and individuals, scope and aims. However from several points of view the word "continuity" has a factual support.
The main purpose of the national conference is to bring together physicists from various institutions, universities, research laboratories, colleges, and high schools, to discuss all matters referring to our profession and activity. And problems appear more and more acute in the present stage of historical development of our country.
Equally important is to watch to what extent the standard of research and education in physics correspond to the mainstream of the world science and to what extent we find the physics in Romania imbedded in .the world's civilization.
The sub-title "trends in physics" , adopted from the European general conferences, expresses exactly the desire of the organizers to have an overview of the status of research and education in physics in our country capable to constitute a frame for further steps and a signal for competent authorities in science policy - and for physicists themselves, too. From this point of view the Romanian Physical Society is the ideal institution, if not the only one, capable to engage on such a task. Specialized conferences more, or less successful, have been abundant during the last few years and they are extremely necessary. They solve punctual problems of scientific communication and cooperation. National conferences are expected to be a general real forum for physics promotion and advancement in Romania.
The present book contains the abstracts of contributions submitted to the conference. They will be catalogued by several international agencies (i.e. INIS-AIEA) and will be kept in the web page of RPS. As we have found an increase of the standard of presentation by the authors no paper was rejected, though we recognize that there are many misprints and language mistakes in many texts. The meaning and the intrinsic value of these texts are however transparent. Unfortunately the organizers did not have the means and time to make the necessary corrections; we operated in general to the printing aspect and uniformity of presentations. Regarding the content, spelling, grammar and logical flow, these remain entirely as the responsibility of the authors themselves.
Articles
The main purpose of the national conference is to bring together physicists from various institutions, universities, research laboratories, colleges, and high schools, to discuss all matters referring to our profession and activity. And problems appear more and more acute in the present stage of historical development of our country.
Equally important is to watch to what extent the standard of research and education in physics correspond to the mainstream of the world science and to what extent we find the physics in Romania imbedded in .the world's civilization.
The sub-title "trends in physics" , adopted from the European general conferences, expresses exactly the desire of the organizers to have an overview of the status of research and education in physics in our country capable to constitute a frame for further steps and a signal for competent authorities in science policy - and for physicists themselves, too. From this point of view the Romanian Physical Society is the ideal institution, if not the only one, capable to engage on such a task. Specialized conferences more, or less successful, have been abundant during the last few years and they are extremely necessary. They solve punctual problems of scientific communication and cooperation. National conferences are expected to be a general real forum for physics promotion and advancement in Romania.
The present book contains the abstracts of contributions submitted to the conference. They will be catalogued by several international agencies (i.e. INIS-AIEA) and will be kept in the web page of RPS. As we have found an increase of the standard of presentation by the authors no paper was rejected, though we recognize that there are many misprints and language mistakes in many texts. The meaning and the intrinsic value of these texts are however transparent. Unfortunately the organizers did not have the means and time to make the necessary corrections; we operated in general to the printing aspect and uniformity of presentations. Regarding the content, spelling, grammar and logical flow, these remain entirely as the responsibility of the authors themselves.
Articles
Synthesis of a chitosan-based chelating resin and its application to the selective concentration and ultratrace determination of silver in environment
Abstract
A novel chelating resin using chitosan as a base material, ethylenediamine-type chitosan, has been synthesized for the first time in the present study, and applied to the collection/concentration of ultratrace amounts of silver in environmental water samples. In the present study, ultratrace amounts of silver collected on the resin were eluted and determined by ICP-MS. The resin packed in a 1 mL mini column could adsorb silver selectively and quantitatively at a flow rate of 2 mL min−1 in the wide pH range from 1 to 8, and silver adsorbed on the resin could be easily recovered by passing 1 M nitric acid as an eluent into the column. High adsorption capacity for silver at pH 5, 0.37 mmol mL−1 of the resin, was achieved, and t1/2 of the adsorption is less than 5 min. The effect of chloride on the collection of silver was examined by varying chloride concentrations from 10−4 to 0.75 M; the results showed that the present resin can be used for the collection/concentration of ultratrace amounts of silver in natural waters, as well as seawater. To ensure the accuracy and the precision of the method, CASS-4 near shore seawater reference material from the NRCC has been analyzed. This is not a certified SRM for silver, but has been used for comparative silver analysis by several groups, who report very similar results to those that are reported here. The developed method using ethylenediamine-type chitosan resin gives 0.7 pg mL−1 of the detection limit when 50-fold enrichment was used. The proposed method was successfully applied to the determination of silver in tap, river, and seawater samples.
Keywords: Chelating resin; Chitosan; Determination of silver; Environmental water samples; ICP-MS
Article Outline
- 1. Introduction
- 2. Experimental
- 2.1. Instruments
- 2.2. Reagents and solutions
- 3. Procedure
- 3.1. Synthesis of ethylenediamine-type chitosan resin
- 3.2. Mini column procedure for collection and concentration of silver
- 4. Results and discussion
- 4.1. Characteristics of the ethylenediamine-type chitosan resin
- 4.2. Adsorption capacity of ethylenediamine-type chitosan resin
- 4.3. Adsorption behavior of metal ions on ethylenediamine-type chitosan resin
- 4.4. Detection limit
- 4.5. Effect of chloride ion
- 4.6. Speciation of silver in water and adsorption mechanism of silver on the ethylenediamine-type chitosan resin
- 4.7. Determination of silver in CASS-4 nearshore seawater reference material
- 4.8. Determination of silver in tap, river, and seawater samples
- 5. Conclusion
- Acknowledgements
- References
Quality Traceability DependabilityWorld wide
ASTM D97 method for determination of the pour point of petroleum products. ...... K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr. Y Zr Nb ... Na Mg. Al. P. K Ca Sc Ti V. Cu Zn. As. Rb. Tc Ru Rh Pd Ag. In. Sb. Cs Ba La Hf Ta W Re Os .... Th Pa U. Mo. Mg. Al. P. Cr Mn Fe Co Ni. Ba. Pb. B. Na. Si. K. Ti V. Zn ...
[PDF] VHGCatalog_Final 92607B.qxp:Layout 1
[PDF] VHGCatalog_Final 92607B.qxp:Layout 1
SUMMARIES OF PHYSICAL RESEARCH IN METALLURGY, SOLID STATE PHYSICS, AND CERAMICS
I. PRODUCTION, TREATMENT, AND PROPERTIES OF MATERIALS
A. Metallurgy of Reactor Materials
Metallurgical and Other Investigations on Special Metals, Other Materials-5 and Processes
Purification of Alkali Halides-8
Physical Metallurgy of Uranium-9
Uranium A13 oys -10
Physical Metallurgy of Plutonium and Its Alloys-12
Niobium Phase Diagrams-13
System Zirconium-Iron-Tin -14
Uranium Phase Equilibria Studies-15
Bonding Fundamentals -16
Basic Studies Relevant to the Liquid Metal Fuel Reactor-17
Transformation Characteristics of Zirconium-Niobium Alloys-19
Study of Inclusions in Uranium-21
Fatigue Behavior of Dilute Alloys of Niobium -22
Physical Metallurgy of Uncommon Metals -23
Constitution of Uranium Alloys-24
Fundamentals of Diffusional Bonding-25
Phase Equilibria Studies of Alloy Systems Involving One or More Alkali
and Alkaline Earth Metals as Components -26
Basic Properties of Light Metal Hydrides -27
B. Materials Preparation
Preparation, Structure and Properties of Uranium Compounds-31
Metal Purification and Crystal Preparation-32
Preparation of Semiconducting Materials-33
C. Refractory Materials
Basic Research In Ceramics-37
Properties of Ceramics at Elevated Temperatures-38
Research on Graphite-39
Volume Change on Melting 1102 -40
Ceramics Research-41
D. Corrosion and Oxidation Studies
Basic Corrosion Studies-45
Scaling of Zirconium at Elevated Temperatures-46
Study of the Films Formed on Zirconium-Niobium Alloys in Oxygen Atmospheres -47
Investigation of Phenomena Related To Liquid Metal Corrosion-48
Corrosion of Nuclear Metals -49
Electrochemical Studies on the Corrosion of Nuclear Reactor Metals-50
[PDF] SUMMARIES OF PHYSICAL RESEARCH IN METALLURGY, SOLID STATE PHYSICS ..
A. Metallurgy of Reactor Materials
Metallurgical and Other Investigations on Special Metals, Other Materials-5 and Processes
Purification of Alkali Halides-8
Physical Metallurgy of Uranium-9
Uranium A13 oys -10
Physical Metallurgy of Plutonium and Its Alloys-12
Niobium Phase Diagrams-13
System Zirconium-Iron-Tin -14
Uranium Phase Equilibria Studies-15
Bonding Fundamentals -16
Basic Studies Relevant to the Liquid Metal Fuel Reactor-17
Transformation Characteristics of Zirconium-Niobium Alloys-19
Study of Inclusions in Uranium-21
Fatigue Behavior of Dilute Alloys of Niobium -22
Physical Metallurgy of Uncommon Metals -23
Constitution of Uranium Alloys-24
Fundamentals of Diffusional Bonding-25
Phase Equilibria Studies of Alloy Systems Involving One or More Alkali
and Alkaline Earth Metals as Components -26
Basic Properties of Light Metal Hydrides -27
B. Materials Preparation
Preparation, Structure and Properties of Uranium Compounds-31
Metal Purification and Crystal Preparation-32
Preparation of Semiconducting Materials-33
C. Refractory Materials
Basic Research In Ceramics-37
Properties of Ceramics at Elevated Temperatures-38
Research on Graphite-39
Volume Change on Melting 1102 -40
Ceramics Research-41
D. Corrosion and Oxidation Studies
Basic Corrosion Studies-45
Scaling of Zirconium at Elevated Temperatures-46
Study of the Films Formed on Zirconium-Niobium Alloys in Oxygen Atmospheres -47
Investigation of Phenomena Related To Liquid Metal Corrosion-48
Corrosion of Nuclear Metals -49
Electrochemical Studies on the Corrosion of Nuclear Reactor Metals-50
[PDF] SUMMARIES OF PHYSICAL RESEARCH IN METALLURGY, SOLID STATE PHYSICS ..
Chelating Sorbents in Inorganic Chemical Analysis
INTRODUCTION
Accurate analysis of various complex samples (natural and waste waters, geological, biological and industrial materials, substances of high purity), especially at trace levels, is one of the most difficult and complicatedanalytical tasks.
The rapid development of electronic instrumentation has created powerful analytical tools for trace element determination. At the same time, matrix effects (which can give erroneous results) and the extent of separation chemistry in instrumental methods have become evident.1
In the last years, the importance of separation and concentration techniques involving chelating sorbents in the trace analysis has risen substantially.
Pre-treatment of an aqueous sample by the sorption technique not only increases the ion concentration to a detectable level but also eliminates matrix effects. The use of chelating sorbents can provide a concentration factor up to several hundred folds, better separation of interferent ions, high efficiency and rate of process, and the possibility of combining with different determination methods.2¿5
A chelating sorbent essentially consists of two components: the chelate forming functional group and the polymeric matrix or the support; the properties of both components determine the features and the applications of the respective material.
[PDF] Chelating Sorbents in Inorganic Chemical Analysis
Accurate analysis of various complex samples (natural and waste waters, geological, biological and industrial materials, substances of high purity), especially at trace levels, is one of the most difficult and complicatedanalytical tasks.
The rapid development of electronic instrumentation has created powerful analytical tools for trace element determination. At the same time, matrix effects (which can give erroneous results) and the extent of separation chemistry in instrumental methods have become evident.1
In the last years, the importance of separation and concentration techniques involving chelating sorbents in the trace analysis has risen substantially.
Pre-treatment of an aqueous sample by the sorption technique not only increases the ion concentration to a detectable level but also eliminates matrix effects. The use of chelating sorbents can provide a concentration factor up to several hundred folds, better separation of interferent ions, high efficiency and rate of process, and the possibility of combining with different determination methods.2¿5
A chelating sorbent essentially consists of two components: the chelate forming functional group and the polymeric matrix or the support; the properties of both components determine the features and the applications of the respective material.
[PDF] Chelating Sorbents in Inorganic Chemical Analysis
Biosorption of heavy metals by Saccharomyces cerevisiae: A review
Abstract
Heavy metal pollution has become one of the most serious environmental problems today. Biosorption, using biomaterials such as bacteria, fungi, yeast and algae, is regarded as acosteffective biotechnology for the treatment of high volume and low concentration complex wastewaters containing heavy metal(s) in the order of 1 to 100 mg/L. Among the promising biosorbents for heavy metal removal which have been researched during the past decades, Saccharomyces cerevisiae has received increasing attention due to the unique nature in spite of its mediocre capacity for metal uptake compared with other fungi. S. cerevisiae is widely used in food and beverage production, is easily cultivated using cheap media, is also a by-product in large quantity as a waste of the fermentation industry, and is easily manipulated at molecular level.
The state of the art in the field of biosorption of heavy metals by S. cerevisiae not only in China, but also worldwide, is reviewed in this paper, based on a substantial number of relevant references published recently on the background of biosorption achievements and development. Characteristics of S. cerevisiae in heavy metal biosorption are extensively discussed. The yeast can be studied in various forms for different purposes. Metal-binding capacity for various heavy metals by S. cerevisiae under different conditions is compared. Lead and uranium, for instances, could be removed from dilute solutions more effectively in comparison with other metals. The yeast biosorption largely depends on parameters such as pH, the ratio of the initial metal ion and initial biomass concentration, culture conditions, presence of various ligands and competitive metal ions in solution and to a limited extent on temperature. An assessment of the isotherm equilibrium model, as well as kinetics was performed. The mechanisms of biosorption are understood only to a limited extent. Elucidation of the mechanism of metal uptake is a real challenge in the field of biosorption. Various mechanism assumptions of metal uptake by S. cerevisiae are summarized.
Article Outline
- 1. Introduction
- 2. Advantages of S. cerevisiae as biosorbents in metal biosorption
- 3. Forms of S. cerevisiae in biosorption research
- 4. Biosorption capacity of S. cerevisiae
- 4.1. Metal ion uptake
- 4.2. Biosorption capacity
- 4.3. Selectivity and competitive biosorption by S. cerevisiae
- 4.4. Comparison with other biomaterials
- 5. Influential factors
- 5.1. Properties of metal ions in solution
- 5.2. Environmental conditions
- 5.2.1. pH
- 5.2.2. Temperature
- 5.2.3. Contact time
- 5.2.4. Competing ions/co-ions
- 5.2.5. Initial concentration of metal ions and biomass
- 5.2.6. Composition of cultural medium
- 5.2.6.1. Glucose
- 5.2.6.2. Other compositions of cultural medium
- 5.2.7. Cell age
- 6. Pretreatment
- 7. Biosorption equilibrium isotherm models and kinetics models
- 7.1. Equilibrium isotherm models
- 7.2. Kinetics of biosorption
- 7.3. Process of metal uptake
- 7.4. Kinetic models for S. cerevisiae
- 8. Biosorption mechanism by the cell of S. cerevisiae
- 8.1. Extracellular accumulation/precipitation
- 8.2. Cell surface sorption/precipitation
- 8.3. Intracellular accumulation/ precipitation
- 9. Instrumental tools and techniques used in metal biosorption studies
- 10. Discussions and future directions
- 10.1. Mechanism research
- 10.2. Application of biosorption technology
- 10.3. Screening of biomaterials
- 10.4. Hybrid technology
- Acknowledgements
- References
Organic Reagents in Spectrophotometric Analysis
1985 Russ. Chem. Rev. 54 1074-1090 doi: 10.1070/RC1985v054n11ABEH003158 
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Abstract.
The spectrophotometric analytical methods using organic reagents in modern chemistry are discussed. Certain new organic reagents, synthesised in recent years, are presented. New methodological procedures in spectrophotometric analysis and the possibilities of the available apparatus are examined. The advances achieved in the development of the theoretical principles of the action of organic reagents are described and a new approach to the explanation of the reactivity of organic compounds is put forward.
The bibliography includes 200 references.
Atomic Spectrometry Update. Industrial analysis: metals, chemicals and advanced materials
This Atomic Spectrometry Update is the latest in an annual series appearing under the title Industrial Analysis. Due to changes in the abstracting system that the ASU reviews depend upon, there has been a slight change in the quantity and quality of the abstracts that were presented to the writing team this year. For most of the review no significant changes have occurred. However, for several specialised topics such as Glasses and Catalysts the amount of information has both increased in relevance and quantity. In contrast Table 3 is reduced this year due to the abstracting changes. Hopefully, more refinements of the new system will bring in more benefits as to the quality of the review in the coming years.
New developments in solid sample introduction continue to be reported both for ferrous and non-ferrous metal analysis. The technique that has shown much promise in this area is laser induced breakdown spectrometry (LIBS) and several interesting reports were received.
In contrast to the 2000 review, where petroleum additives were a hot topic, only one paper referring to petroleum additives was received. Solid phase micro-extraction (SPME) has also been employed in conjunction with Raman spectroscopy to determine the petroleum contamination of water. The analysis of coal in this review period is split mainly into two areas: the analysis of total trace metals in the coal and the determination of elements which raise environmental concerns.
Papers detailing pre-concentration using various functionalised resins, e.g., XAD-2 and XAD-16, solid phase extraction and various organic chemicals have a large contribution to this year's review. This year there has been a more general application of analytical techniques for analysis of inorganic materials. As in previous years, solid sample analysis has been a prominent feature, with the development of a portable XRF device, several ETA-AAS studies and some interesting secondary ion mass spectrometry work being reported.
Inductively coupled plasma mass spectrometry (ICP-MS), in each of its variants, continues to be the dominant technique in the application of analytical atomic spectroscopy to the analysis of nuclear materials.
One point for avid review readers is the quantity of rare earth element papers mentioned in Table 3 this year. This may be due to either the new abstracting system or to the fact that our colleagues who publish in this area around the world are growing weary of this field of research.
New developments in solid sample introduction continue to be reported both for ferrous and non-ferrous metal analysis. The technique that has shown much promise in this area is laser induced breakdown spectrometry (LIBS) and several interesting reports were received.
In contrast to the 2000 review, where petroleum additives were a hot topic, only one paper referring to petroleum additives was received. Solid phase micro-extraction (SPME) has also been employed in conjunction with Raman spectroscopy to determine the petroleum contamination of water. The analysis of coal in this review period is split mainly into two areas: the analysis of total trace metals in the coal and the determination of elements which raise environmental concerns.
Papers detailing pre-concentration using various functionalised resins, e.g., XAD-2 and XAD-16, solid phase extraction and various organic chemicals have a large contribution to this year's review. This year there has been a more general application of analytical techniques for analysis of inorganic materials. As in previous years, solid sample analysis has been a prominent feature, with the development of a portable XRF device, several ETA-AAS studies and some interesting secondary ion mass spectrometry work being reported.
Inductively coupled plasma mass spectrometry (ICP-MS), in each of its variants, continues to be the dominant technique in the application of analytical atomic spectroscopy to the analysis of nuclear materials.
One point for avid review readers is the quantity of rare earth element papers mentioned in Table 3 this year. This may be due to either the new abstracting system or to the fact that our colleagues who publish in this area around the world are growing weary of this field of research.
| Contents | |
|---|---|
| 1 | Metals |
| Table 1 | Summary of analyses of metals |
| 1.1 | Ferous metals and alloys |
| 1.2 | Non-ferrous metals and alloys |
| 2 | Chemicals |
| 2.1 | Petroleum and petroleum products |
| 2.1.1 | Petroleum products |
| 2.1.2 | Fuels |
| 2.1.3 | Oils |
| 2.2 | Organic chemicals and solvents |
| 2.2.1 | Chemicals |
| 2.2.2. | Solvents |
| 2.3. | Inorganic chemicals and acids |
| 2.4. | Nuclear materials |
| Table 2 | Summary of analyses of chemicals |
| 3 | Advanced materials |
| 3.1 | Polymeric materials and composites |
| 3.2 | Semiconductor and conducting materials |
| 3.3 | Glasses |
| 3.4 | Ceramics and refractories |
| Table 3 | Summary of analyses of advanced materials |
| 3.5. | Catalysts |
| 4 | References |
Thursday, March 5, 2009
Spectrophotometric
Beckman Instruments, Inc.: Bulletin 134-D. Fullerton, California. ...... been the basis for many published methods for the determination of ...... ments Ag, Al, B, Ba, Be, Or, Co, Cu, Fe, Mn,. Mo, Ni, Pb, Sn, Sr, Ti, V, Zn, and Zr are deter- ... Al, Ba, Mn, Ni, Cs, Sn,. Sr, Cr, Zn, Pb, Mo and Cd are monitored with ...
PDF: SPECTROPHOTOMETRY
Study on color reaction of 2-(2-quinolylazo)-5-dimethylaminoanline with palladium and its application
Abstrasct
A new chromogenic reagent, 2-(2-quinolylazo)-5-dimethylaminoaniline (QADMAA) was synthesized. A sensitive, selective and rapid method for the determination of palladium based on the rapid reaction of palladium(II) with QADMAA was developed. In the presence of 0.5-2.5 mol/L of hydrochloric acid solution and cetyl trimethylammonium bromide (CTMAB) medium, QADMAA reacts with palladium to form a violet complex of a molar ratio 1:2 (palladium to QADMAA). The molar absorptivity of the chelate is 1.35¡Á105 L.mol-1.cm-1 at 600 nm. Beer¡¯s law is obeyed in the range of 0.01~ 0.6 m g/ml. The relative standard deviation for eleven replicate sample of 0.2 m g/ml level is 1.02 %. This method had been applied to the determination of palladium with good results.
Keywords 2-(2-quinolylazo)-5-dimethylaminoaniline; palladium; spectrophotometry
Study on color reaction of 2-(2-quinolylazo)-5-dimethylaminoanline with palladium and its application
Abstrasct
A new chromogenic reagent, 2-(2-quinolylazo)-5-dimethylaminoaniline (QADMAA) was synthesized. A sensitive, selective and rapid method for the determination of palladium based on the rapid reaction of palladium(II) with QADMAA was developed. In the presence of 0.5-2.5 mol/L of hydrochloric acid solution and cetyl trimethylammonium bromide (CTMAB) medium, QADMAA reacts with palladium to form a violet complex of a molar ratio 1:2 (palladium to QADMAA). The molar absorptivity of the chelate is 1.35¡Á105 L.mol-1.cm-1 at 600 nm. Beer¡¯s law is obeyed in the range of 0.01~ 0.6 m g/ml. The relative standard deviation for eleven replicate sample of 0.2 m g/ml level is 1.02 %. This method had been applied to the determination of palladium with good results.
Keywords 2-(2-quinolylazo)-5-dimethylaminoaniline; palladium; spectrophotometry
Supramolecular function of fluorescent probe/cyclodextrincomplex sensors in water
This paper reviewed the supramolecular function of fluorescent probe/cyclodextrin (CyD) complexes for ion and molecule recognition in water. Benzo-15-crown-5 fluoroionophores, Cn-15C5 (n=1, 3, 5), with different alkyl spacer lengths were first examined to develop supramolecular Cn-15C5/γ-CyD complex sensors for alkali metal-ion recognition in water. In organic solutions, C3-15C5 shows moderate Na+selectivity based on 1:1 complex formation. However, the C3-15C5/γ-CyD complex is found to selectively respond to K+ion in water and to exhibit pyrene dimer emission. An equilibrium analysis of the γ-CyD inclusion complexes in water reveals that the major component for the dimer emission is a 2:1:1 complex of C3-15C5 with K+and γ-CyD. Although the K+sensitivity of the C5-15C5/γ-CyD complex is comparable to that of the C3-15C5/γ-CyD complex, it also responds to Na+. The fluoroionophore C1-15C5, which has the shortest methylene spacer, exhibits no response to alkali metal cations in the presence of γ-CyD. Thus, the response function is strongly affected by the alkyl spacer length of Cn-15C5, and the highest K+selectivity in water is obtained for the C3-15C5/γ-CyD complex. The boronic acid fluoroionophore C4-PB/β-CyD complex binds sugars and produces increased fluorescence emission in water. A pH-fluorescence profile for the C4-PB/β-CyD complex reveals that the fluorescence intensity increases upon the formation of the boronate conjugate base. Upon the addition of fructose, the apparent pKa decreases to a lower pH, resulting in increased fluorescence at neutral pH. The fluorescence emission response of the C4-PB/β-CyD complex upon sugar binding appears to be due to suppression of the photoinduced electron transfer (PET) from the pyrene donor to the trigonal arylboronic acid acceptor.
REVIEW OF HEAVY METALS
1. INTRODUCTION
In natural aquatic ecosystems, metals occur in low concentrations, normally at the nanogram to microgram per litre level. In recent times, however, the occurrence of metal contaminants' especially the heavy metals in excess of natural loads, has become a problem of increasing concern. This situation has arisen as a result of the rapid growth of population, increased urbanisation, expansion of industrial activities, exploration and exploitation of natural resources, extension of irrigation and other modern agricultural practices as well as the lack of environmental regulations.
At the global level the scientific community has investigated some of these problems and the results have been published in several reviews and books (Nriagu, 1989; Förstner and Wittmann, 1981; Salomons and Förstner, 1984). Most of the present introductory material is based on these sources.
Unlike other pollutants like petroleum hydrocarbons and litter which may visibly build up in the environment, trace metals may accumulate, unnoticed, to toxic levels. Thus problems associated with trace metal contamination were first highlighted in the industrially advanced countries because of their larger industrial discharges and especially by incidents of mercury and cadmium pollution in Sweden and Japan (Kurland et al., 1960; Nitta, 1972; Goldberg, 1976). In spite of the relatively low level of industrial activity in less developed regions such as Africa, there is nevertheless growing awareness of the need for rational management of aquatic resources including control of waste discharges into the environment. This becomes even more important in view of the expected increases in industrial and urban activities in all parts of the continent.
Existing information on various environmental problems has been reviewed by Dejoux (1988) in a monograph of pollution in African inland waters and by Phillips (1991) on a worldwide basis on tropical marine ecosystems. These publications showed that the existing information on Africa is scattered and scarce, and therefore demonstrated the need for a more precise and specific review of the occurrence of trace heavy metals in various aquatic environmental compartments in the continent.
For effective water pollution control and management there is a need for a clear understanding of the inputs (loads), distribution and fate of contaminants, including trace metals from land-based sources into aquatic ecosystems. In particular, the quantities and qualities need to be considered together with the distribution pathways and fate and the effects on biota.
The need to make an assessment of the level of heavy metal contamination in the African environment has led to the initiation of several pollution monitoring programmes and research work in various universities and scientific institutions in the region. The most relevant programmes are the Mediterranean pollution monitoring programme (MEDPOL) covering also North Africa, the West and Central Africa marine pollution and research programme (WACAF 2) and the Eastern Africa marine pollution and research programme (EAF/6).
During the last decade, there have also been considerable improvements in the sampling and analytical techniques for trace metals. These, coupled with international intercomparison exercises, have facilitated the generation of more reliable data. The present paper thus attempts to compile and analyze the available information on the occurrence of trace metals in both freshwater and marine ecosystems of Africa as a contribution towards the formulation of rational management policies for aquatic resources in the continent.
The decision to review freshwater and marine data jointly is a result of the need to have a holistic approach that could influence future control strategies.
In natural aquatic ecosystems, metals occur in low concentrations, normally at the nanogram to microgram per litre level. In recent times, however, the occurrence of metal contaminants' especially the heavy metals in excess of natural loads, has become a problem of increasing concern. This situation has arisen as a result of the rapid growth of population, increased urbanisation, expansion of industrial activities, exploration and exploitation of natural resources, extension of irrigation and other modern agricultural practices as well as the lack of environmental regulations.
At the global level the scientific community has investigated some of these problems and the results have been published in several reviews and books (Nriagu, 1989; Förstner and Wittmann, 1981; Salomons and Förstner, 1984). Most of the present introductory material is based on these sources.
Unlike other pollutants like petroleum hydrocarbons and litter which may visibly build up in the environment, trace metals may accumulate, unnoticed, to toxic levels. Thus problems associated with trace metal contamination were first highlighted in the industrially advanced countries because of their larger industrial discharges and especially by incidents of mercury and cadmium pollution in Sweden and Japan (Kurland et al., 1960; Nitta, 1972; Goldberg, 1976). In spite of the relatively low level of industrial activity in less developed regions such as Africa, there is nevertheless growing awareness of the need for rational management of aquatic resources including control of waste discharges into the environment. This becomes even more important in view of the expected increases in industrial and urban activities in all parts of the continent.
Existing information on various environmental problems has been reviewed by Dejoux (1988) in a monograph of pollution in African inland waters and by Phillips (1991) on a worldwide basis on tropical marine ecosystems. These publications showed that the existing information on Africa is scattered and scarce, and therefore demonstrated the need for a more precise and specific review of the occurrence of trace heavy metals in various aquatic environmental compartments in the continent.
For effective water pollution control and management there is a need for a clear understanding of the inputs (loads), distribution and fate of contaminants, including trace metals from land-based sources into aquatic ecosystems. In particular, the quantities and qualities need to be considered together with the distribution pathways and fate and the effects on biota.
The need to make an assessment of the level of heavy metal contamination in the African environment has led to the initiation of several pollution monitoring programmes and research work in various universities and scientific institutions in the region. The most relevant programmes are the Mediterranean pollution monitoring programme (MEDPOL) covering also North Africa, the West and Central Africa marine pollution and research programme (WACAF 2) and the Eastern Africa marine pollution and research programme (EAF/6).
During the last decade, there have also been considerable improvements in the sampling and analytical techniques for trace metals. These, coupled with international intercomparison exercises, have facilitated the generation of more reliable data. The present paper thus attempts to compile and analyze the available information on the occurrence of trace metals in both freshwater and marine ecosystems of Africa as a contribution towards the formulation of rational management policies for aquatic resources in the continent.
The decision to review freshwater and marine data jointly is a result of the need to have a holistic approach that could influence future control strategies.
SOIL GENESIS ON PERALKALINE FELSICS IN BIG BEND NATIONAL PARK, TEXAS
Abstract
Soil genesis involving felsic rocks frequently involves understanding the roles of climate and time on the transformations of the primary minerals into secondary products. This study focuses on the weathering of peralkaline felsics in a semiarid climate. Soils and fresh parent materials were collected from different microclimate regimes in the Chisos Mountains of Big Bend National Park, Texas. Soils in the Chisos mountains generally have either a mollic-argillic-rock or a mollic-rock horizon sequence, whereas other sites at lower and drier locations have an ochric-rock horizon sequence. Atmospheric deposition of Ca and Sr and wind deflation of clay are important attributes of soil genesis. Elemental loss rates of Si, Al, K, Na, and other elements are appreciable, suggesting that leaching has been important to the soil formation. Iron oxide formation, which is related to the moisture regime, is greater in soils having wetter microclimates. Solution chemistry suggests that Mg concentrations are appropriate for smectite synthesis and maintenance, potassium concentrations reflect the presence of feldspar, sodium concentrations reflect their loss rates because of leaching, and calcium reflects the presence of calcite. The rare earth elements similarly demonstrate loss rates consistent with chemical weathering. In general, chemical weathering of feldspars, atmospheric deposition of Ca and Sr, and wind deflation are important pedogenic processes.
Digestion of Solid Matrices Desk Study - Horizontal
SUMMARY
Choice of digestion methods
The report in hand concerns an evaluation of potential for horizontal standardisation for the digestion of samples prior to the determination of trace elements covering sludge, soil, treated biowaste and neighbouring fields.
The detailed comparison of standards for the digestion prior to the determination of trace elements demonstrates the possibility of preparing horizontal standards in this field, however
investigation has to be initiated prior to the establishment.
From an environmental impact evaluation perspective the composition derived from either "partial" or "total" digestion is hardly relevant, as the fraction which even under extreme environmental condition will be brought into solution (and made available for plants etc.) is several orders of magnitude lower. Thus for control purposes or for monitoring or evaluation of developments in element concentration, the use of "partial" methods are considered acceptable.
However, it is of vital importance that the methods provide comparable results with a sufficiently high reproducibility for the elements and matter in question.
In many European countries, digestion methods used for solid environmental samples such as waste, sludge and soil are based on the use of aqua regia in accordance with the relevant European and International standards for the different areas. However, in some European countries, e.g. the Nordic countries, the digestion methods are based on the use of nitric acid.
The reason for this choice being the smaller interference effects from using nitric acids on some of the subsequent analytical procedures.
Polarized Zeeman Absorption Atomic Spectrophotometer
Easier Operation, Higher Reliable Analyses,
and Higher Sensitivity Than Ever Before
This is the concept of Z-series of the polarized Zeeman AAS.
Three models are available to meet your specific need.
High Quality
Compact
Useful Design
Excellent Sensitivity using Zeeman Method and Dual Detector.
Space of Installation is Reduced (Z-2300/2700 )
Slim designed with built-in Graphite Furnace Autosampler
[PDF] Untitled
and Higher Sensitivity Than Ever Before
This is the concept of Z-series of the polarized Zeeman AAS.
Three models are available to meet your specific need.
High Quality
Compact
Useful Design
Excellent Sensitivity using Zeeman Method and Dual Detector.
Space of Installation is Reduced (Z-2300/2700 )
Slim designed with built-in Graphite Furnace Autosampler
[PDF] Untitled
Concentration Methods for the Determination of Trace Elements
Yurii A Zolotov 1980 Russ. Chem. Rev. 49 683-694 doi: 10.1070/RC1980v049n07ABEH002497
PDF (1.71 MB) References Articles citing this article
Yurii A Zolotov
Abstract. Methods of concentrating trace constituents are discussed, and the quantitative parameters used to describe them are defined. The main methods of concentration (extraction, sorption, coprecipitation, evaporation, etc.) are examined and compared. Rational combinations of methods of concentration and methods of determination of trace elements are recommended, and successful examples of such combinations are quoted. Special aspects of concentration methods applicable to the analysis of high-purity materials and of natural waters are discussed. 114 references.
PDF (1.71 MB) References Articles citing this article
Yurii A Zolotov
Abstract. Methods of concentrating trace constituents are discussed, and the quantitative parameters used to describe them are defined. The main methods of concentration (extraction, sorption, coprecipitation, evaporation, etc.) are examined and compared. Rational combinations of methods of concentration and methods of determination of trace elements are recommended, and successful examples of such combinations are quoted. Special aspects of concentration methods applicable to the analysis of high-purity materials and of natural waters are discussed. 114 references.
FLUOROMETRIC DETERMINATION OF IRON WITH SOME N-ARYL-3-AMINOPROPIONIC ACIDS
Iron is essential to most life forms and to normal human physiology. Iron is an integral part of many proteins and enzymes that maintain good health. In humans, iron is an essential component of proteins involved in oxygen transport [ , ]. It is also essential for the regulation of cell growth and differentiation [ , ]. A deficiency of iron limits oxygen delivery to cells, resulting in fatigue, poor work performance, and decreased immunity [1, - ]. On the other hand, excess amounts of iron can result in toxicity and even death [ ].
Therefore the element is necessary for control in food products and objects of environment (corresponding norms are presented in table 1). Also small contents of iron are necessary for control in various metallurgical objects [8].
Articles
Therefore the element is necessary for control in food products and objects of environment (corresponding norms are presented in table 1). Also small contents of iron are necessary for control in various metallurgical objects [8].
Articles
Wednesday, March 4, 2009
Highly Selective and Sensitized Spectrophotometric Determination of Iron (III) Following Potentiometric Study
Abstract References Full Text: PDF (Size: 261K) Related Articles Citation Tracking
Article
Highly Selective and Sensitized Spectrophotometric Determination of Iron (III) Following Potentiometric Study
Ardeshir Shokrollahi, Mehrorang Ghaedi *, Hamid Reza Rajabi
Chemistry Department Yasouj University Yasouj Iran 75914-353
email: Mehrorang Ghaedi (m_ghaedi@mail.yu.ac.ir)
*Correspondence to Mehrorang Ghaedi, Chemistry Department Yasouj University Yasouj Iran 75914-353, Tel.Fax. (+98)-741-2223048
setDOI("ADOI=10.1002/adic.200790067")
Abstract
A simple, selective and sensitized spectrophotometric method for determination of trace amounts of Fe3+ ion in tap and waste water solutions has been described. The spectrophotometric determination of Fe3+ ion using Ferron in the presence of N,N-Dodecytrimethylammonium bromide (DTAB) has been carried out. The Beer's law is obeyed over the concentration range of 0.05-2.6 g mL-1 of Fe3+ ion with the relative standard deviation (RSD %) <0.2 % and the molar absorptivity of complexes in pH 3.5 is 3.8×103 L mol-1 cm-1.
Potentiometric pH titration has been used for prediction of protonation constants of ferron, and evaluating its stoichiometry and respective stability constant with Fe3+ ion. As it is obvious the most likely species of ferron alone and its complexes are LH (log=7.64), LH2 (logK=10.52), LH3 (logK=11.74) and ML2 (log= 23.68), ML3 (log= 23.68), ML3H (log= 23.68), ML3H2 (log= 23.68) and ML(OH)2 (log=23.68) respectively.
Article
Highly Selective and Sensitized Spectrophotometric Determination of Iron (III) Following Potentiometric Study
Ardeshir Shokrollahi, Mehrorang Ghaedi *, Hamid Reza Rajabi
Chemistry Department Yasouj University Yasouj Iran 75914-353
email: Mehrorang Ghaedi (m_ghaedi@mail.yu.ac.ir)
*Correspondence to Mehrorang Ghaedi, Chemistry Department Yasouj University Yasouj Iran 75914-353, Tel.Fax. (+98)-741-2223048
setDOI("ADOI=10.1002/adic.200790067")
Abstract
A simple, selective and sensitized spectrophotometric method for determination of trace amounts of Fe3+ ion in tap and waste water solutions has been described. The spectrophotometric determination of Fe3+ ion using Ferron in the presence of N,N-Dodecytrimethylammonium bromide (DTAB) has been carried out. The Beer's law is obeyed over the concentration range of 0.05-2.6 g mL-1 of Fe3+ ion with the relative standard deviation (RSD %) <0.2 % and the molar absorptivity of complexes in pH 3.5 is 3.8×103 L mol-1 cm-1.
Potentiometric pH titration has been used for prediction of protonation constants of ferron, and evaluating its stoichiometry and respective stability constant with Fe3+ ion. As it is obvious the most likely species of ferron alone and its complexes are LH (log=7.64), LH2 (logK=10.52), LH3 (logK=11.74) and ML2 (log= 23.68), ML3 (log= 23.68), ML3H (log= 23.68), ML3H2 (log= 23.68) and ML(OH)2 (log=23.68) respectively.
Rapid Spectrophotometric Determination of Zirconium(IV)
Rapid Spectrophotometric Determination of Zirconium(IV) with 2,2,3,4-tetrahydroxy–3 -sulpho–5-chloroazobenzene in Alloys
A. Ali HÜSEYİNLİ,1†Fitnat KÖSEOĞLU,2 and Ülkü Dilek UYSAL1
1† Anadolu University, Faculty of Sciences, Department of Chemistry, 26470, Eskişehir, Turkey (E-mail: ahuseyin@anadolu.edu.tr)
2 Gazi University, Gazi Education Faculty, Teknikokullar, 06500, Ankara, Turkey
New o,o/–monoazo reagents have been synthesized using pyrogallol and 2-aminophenol-6-sulphonic acid or its derivatives. Spectrophotometric properties of the complexes formed by the reaction of synthesized monoazo reagents with Zr4+ have been investigated. According to the results it is found that the most sensitive and selective ligand for the Zr4+ is 2,2/,3,4-tetrahydroxy–3/-sulpho–5/-chloroazobenzene (tetrahydroxyazon SCl) and it was used for the direct spectrophotometric determination of Zr4+ion. Tetrahydroxyazon SCl reagent forms a red complex with Zr4+ ion in acidic media up to pH 6. The complex formation is fast and its absorbance reaches to a level immediately where remains constant for more than three days. The metal (M):ligand (L) ratio of the formed complex is 1:1 and the optimal wavelength of the
complex is 496 nm. Under optimum conditions Zr4+ ion acts in accordance with the Beer law at an ion concentration range of 0.08-3.20 μg/mL. The molar absorptivity was found as 34500 Lmol-1cm-1. The determination of Zr4+ was not interfered by Cu2+, Cd2+, Pb2+, Ni2+, Cr3+, Zn2+, Bi3+, U6+, Th4+, Al3+, Be2+, Co2+, Mn2+, Hg2+, halides, phosphates, sulfates, thiocyanides, urea, tartrate, ascorbic acid etc. This method is highly sensitive, selective, very rapid and a simple technique. It has been successfully applied to the determination of Zr4+ ion in an aluminum based certified alloys.
A. Ali HÜSEYİNLİ,1†Fitnat KÖSEOĞLU,2 and Ülkü Dilek UYSAL1
1† Anadolu University, Faculty of Sciences, Department of Chemistry, 26470, Eskişehir, Turkey (E-mail: ahuseyin@anadolu.edu.tr)
2 Gazi University, Gazi Education Faculty, Teknikokullar, 06500, Ankara, Turkey
New o,o/–monoazo reagents have been synthesized using pyrogallol and 2-aminophenol-6-sulphonic acid or its derivatives. Spectrophotometric properties of the complexes formed by the reaction of synthesized monoazo reagents with Zr4+ have been investigated. According to the results it is found that the most sensitive and selective ligand for the Zr4+ is 2,2/,3,4-tetrahydroxy–3/-sulpho–5/-chloroazobenzene (tetrahydroxyazon SCl) and it was used for the direct spectrophotometric determination of Zr4+ion. Tetrahydroxyazon SCl reagent forms a red complex with Zr4+ ion in acidic media up to pH 6. The complex formation is fast and its absorbance reaches to a level immediately where remains constant for more than three days. The metal (M):ligand (L) ratio of the formed complex is 1:1 and the optimal wavelength of the
complex is 496 nm. Under optimum conditions Zr4+ ion acts in accordance with the Beer law at an ion concentration range of 0.08-3.20 μg/mL. The molar absorptivity was found as 34500 Lmol-1cm-1. The determination of Zr4+ was not interfered by Cu2+, Cd2+, Pb2+, Ni2+, Cr3+, Zn2+, Bi3+, U6+, Th4+, Al3+, Be2+, Co2+, Mn2+, Hg2+, halides, phosphates, sulfates, thiocyanides, urea, tartrate, ascorbic acid etc. This method is highly sensitive, selective, very rapid and a simple technique. It has been successfully applied to the determination of Zr4+ ion in an aluminum based certified alloys.
Tungsten and Cobalt in Workplace Atmospheres (ICP Analysis)
Related Information: Chemical Sampling - Tungsten (as W) Insoluble Compounds, Tungsten (as W) Soluble Compounds, Cobalt, Metal, Dust & Fume (as Co)
Method Number: ID-213
Matrix: Air
Analytical Procedure:
The MCE filter is subjected to a sequence of digestion steps using ammonium hydroxide (aqueous ammonia), water, hydrochloric acid, nitric acid, and phosphoric acid. The resulting solution is analyzed by aspiration into the argon stream of an inductively coupled plasma atomic emission spectrometer (ICP-AES).
Monday, March 2, 2009
An Extractive Spectrophotometric Method of Determination of Molybdenum(VI) Using 3-Hydroxy-2-(4-methoxyphenyl)-6-methyl-4H-chromen-4-one
Abstract
3-Hydroxy-2-(4-methoxyphenyl)-6-methyl-4H-chromen-4-one (HL) behaved as a sensitive spectrophotometric reagent for molybdenum(VI). The metal ion formed a yellow complex with the reagent in acetic acid medium. The complex was extractable into 1,2-dichloroethane and the absorbance values remained unchanged for more than one week. Spectral data showed the formation of 1 : 2 species with λmax value at 411 nm. Beer’s law was obeyed over the concentration range of 0—2.3 ppm. The molar absorptivity and Sandell’s sensitivity were calculated to be 5.61 × 104 dm3 mol−1 cm−1 and 0.0017 μg Mo cm−2 respectively, at 411 nm. The effect of as many as 41 cations and 28 anions and complexing agents was studied. Out of these only Sn(II), Ce(IV), citrate, oxalate, disodium dihydrogen ethylenediaminetetraacetate, and hydrogen peroxide interfered seriously. For ten replicate determinations of 1 μg Mo cm−3 the standard deviation was 0.008 with a relative mean error of ±0.09%. The method is simple, selective, precise and rapid. It has been applied satisfactorily to the determination of molybdenum in steels, waters and flue dust samples.
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