scholarly journals The Implications of HClO4 for Dissolving Large Masses of Low Level Os in Metal Sulfides and Factors that Influence Re-Os Dating

2020 ◽  
Vol 10 (18) ◽  
pp. 6218
Author(s):  
Bingyu Gao ◽  
Wenjun Li ◽  
Lianchang Zhang ◽  
Jun Gao
Keyword(s):  
Reference Materials ◽  
Traditional Method ◽  
Isotope Exchange ◽  
Heating Temperature ◽  
Metal Sulfide ◽  
Metal Sulfides ◽  
Sample Weight ◽  
Aqua Regia ◽  
Certified Values ◽  
Larger Sample

In general, no more than 1 g of metal sulfide can be completely digested in 20 mL of inverse aqua regia using the Carius tube technique. In this study, the sample weight increased after adding HClO4 to inverse aqua regia while the volume of acid concurrently decreased significantly. Three grams of metal sulfide were digested in 12 mL of acid (3 mL of HClO4 and 9 mL of inverse aqua regia) via the HClO4-inverse aqua regia method. The results using molybdenite reference materials JDC and HLP mixed with 3 g of pyrite were consistent with certified values. Compared to the traditional method, the HClO4-inverse aqua regia method could dissolve a larger sample mass (3 g) with a smaller volume of acids (12 mL). We simultaneously found that the oxidation of digestion acids greatly affected the Os signal but had no influence on the equilibrium of isotope exchange between 185Re and 190Os spikes in Re and Os samples. Remarkably, the heating temperature was the most significant factor influencing the equilibrium of isotope exchange, and the Os in a sample was not equilibrated with the spike until the heating temperature reached 190 °C.

ZnO nanorods decorated with metal sulfides as stable and efficient counter-electrode materials for high-efficiency quantum dot-sensitized solar cells

2016 ◽  
Vol 4 (21) ◽  
pp. 8161-8171 ◽  
Author(s):  
Chandu V. V. M. Gopi ◽  
Mallineni Venkata-Haritha ◽  
Young-Seok Lee ◽  
Hee-Je Kim
Keyword(s):  
Solar Cells ◽  
Quantum Dot ◽  
Counter Electrode ◽  
Electrode Materials ◽  
High Efficiency ◽  
Zno Nanorods ◽  
Metal Sulfide ◽  
Metal Sulfides ◽  
Sensitized Solar Cells

Metal sulfide decorated with ZnO NRs (ZnO/CoS, ZnO/NiS, ZnO/CuS and ZnO/PbS) were fabricated and used as efficient CEs for QDSSCs.

Recent Advances and the Design Criteria of Metal Sulfide Photocathode and Photoanode for Photoelectrocatalysis

2021 ◽  
Author(s):  
Cui Ying Toe ◽  
Shujie Zhou ◽  
Michael Gunawan ◽  
Xinxin Lu ◽  
Yun Hau Ng ◽  
...  
Keyword(s):  
Optical Properties ◽  
Light Absorption ◽  
Rapid Development ◽  
Metal Sulfide ◽  
Metal Sulfides ◽  
Design Criteria ◽  
Structural And Optical Properties ◽  
Recent Advances ◽  
Favorable Light

Metal sulfides have emerged as promising materials for photoelectrochemical (PEC) applications due to their favorable light absorption ability, tunable structural and optical properties. With the rapid development of PEC systems,...

Design, synthesis, and application of metal sulfides for Li–S batteries: progress and prospects

2020 ◽  
Vol 8 (35) ◽  
pp. 17848-17882 ◽  
Author(s):  
Bo Yan ◽  
Xifei Li ◽  
Wei Xiao ◽  
Junhua Hu ◽  
Lulu Zhang ◽  
...  
Keyword(s):  
High Performance ◽  
Recent Progress ◽  
Review Paper ◽  
Metal Sulfide ◽  
Design Principles ◽  
Metal Sulfides ◽  
Comprehensive Overview ◽  
Design Synthesis

This review paper presents a comprehensive overview of recent progress in the use of metal sulfide for high-performance Li–S batteries with a particular focus on the modified approaches, design principles, synthetic strategies, and representative applications.

scholarly journals The Honey as a Bioindicator of the Environment

2017 ◽  
Vol 24 (4) ◽  
pp. 583-594 ◽  
Author(s):  
Manfred Sager
Keyword(s):  
Rural Areas ◽  
Urban Areas ◽  
Dust Exposure ◽  
Urban Dust ◽  
Plant Origin ◽  
Sample Weight ◽  
Aqua Regia ◽  
Ash Weight ◽  
Experimental Errors ◽  
Adjacent Soil

Abstract Monofloral rape, sunflower, linden and acacia honeys as well as honeys sampled within and around the Austrian towns Vienna and Linz, as well as in rural areas in Lower Austria, were analysed for main and trace elements. The results were tested to be used as indication of urban dust exposure. Main elements of the ash are K, P, and B, which are specific for plant origin. Ash based data correct for dilutions by the sugar matrix. They showed enrichments of Cu, Zn and Mo, whereas the contaminant elements Cd, Pb and Co were found at about the same levels as expectable in dust. Ash-based Al, Fe, Cr and Li were much lower than soil levels obtainable from aqua regia. Among the monofloral honey samples, the effect of adjacent soil was largest for Mn. Most differences between rural areas and urban areas in Vienna and Linz were within experimental errors, both per sample weight and per ash weight. In cases honey samples are considered to trace contaminations, the additional use of ash-based data is recommended.

Dry Ashing, Hydride Generation Atomic Absorption Spectrometric Determination of Arsenic and Selenium in Foods

1982 ◽  
Vol 65 (3) ◽  
pp. 647-650 ◽  
Author(s):  
Gerard K H Tam ◽  
Gladys Lacroix
Keyword(s):  
Detection Limit ◽  
Atomic Absorption ◽  
Reference Materials ◽  
Hydride Generation ◽  
Spectrometric Method ◽  
Flameless Atomic Absorption ◽  
Dry Ashing ◽  
Atomic Absorption Spectrometric ◽  
Certified Values

Abstract A dry ashing, flameless atomic absorption spectrometric method was evaluated to determine arsenic and selenium in foods. Samples were dry-ashed with Mg(N03)2-MgO and dissolved in HC1. Selenate was reduced to selenite by boiling in 4N HC1, and arsenate to arsenite by treatment with KI. Hydrides of arsenic and selenium were generated by the addition of NaBH4 and were swept by nitrogen and hydrogen into a thermally heated silicate tube furnace. The detection limit was about 5 ppb for each element based on a 10 g sample. Analytical results obtained for several samples of NBS reference materials agreed with the certified values. The procedure was evaluated by another laboratory and results were satisfactory.

Insights into charge storage and electroactivation of mixed metal sulfides in alkaline media: NiCoMn ternary metal sulfide nano-needles forming core–shell structures for hybrid energy storage

2019 ◽  
Vol 7 (35) ◽  
pp. 20414-20424 ◽  
Author(s):  
Jaime S. Sanchez ◽  
Afshin Pendashteh ◽  
Jesus Palma ◽  
Marc Anderson ◽  
Rebeca Marcilla
Keyword(s):  
Energy Storage ◽  
Metal Sulfide ◽  
Shell Structures ◽  
Alkaline Media ◽  
Ex Situ ◽  
Metal Sulfides ◽  
Hybrid Energy ◽  
Storage Mechanism ◽  
Hybrid Energy Storage ◽  
Ternary Metal

NiCoMnS2 were subjected to ex situ/operando measurements, shedding light on energy storage mechanism and electroactivation of mixed sulfides in alkaline media.

scholarly journals Application of the lyophilization system for preparation of reference materials for composition of nutrition products

2021 ◽  
Vol 17 (1) ◽  
pp. 35-45
Author(s):  
M. Y. Medvedevskikh ◽  
N. L. Vostrikova ◽  
A. S. Sergeeva ◽  
V. V. Studenok
Keyword(s):  
Reference Materials ◽  
Fat Mass ◽  
Mass Fraction ◽  
Primary Standard ◽  
Poultry Meat ◽  
Chicken Breast ◽  
Homogeneous Material ◽  
Freeze Dried ◽  
Air Dryer ◽  
Certified Values

The article presents the application of the lyophilization system for preparation of reference materials (RM) for composition of nutritive products samples. The purpose of the research was the development of lyophilization procedure of RM for composition of poultry meat samples preparation with certified values of mass fraction of moisture, nitrogen (protein) and fat.The poultry meat of two types was used as the primary material for RM for poultry meat composition preparation -1) white meat (chicken breast); 2) red meat (chicken thigh). The procedure included pounding, boiling, freezing and lyophilisation (syn. freeze drying). The researches for homogeneity were implemented with hot air dryer standard system from the State primary standard GET 173-2017. Measurement of nitrogen (protein) mass fraction was performed on State secondary standard GVET176-1-2010. Measurements of fat mass fraction were performed with accordance to State Primary Reference Measurement Procedure.The total time of lyophilization process for samples № 1 and № 2 was 19 and 28 hours, respectively. The total mass loss for sample № 1 was about 63 %, for sample № 2 was about 65 %. The difference in material moisture mass fraction values of materials dried on different trays of freeze dryer was statistically significant, i. e., material was non-homogeneous. To obtain a homogeneous material, an additional homogenization procedure was performed: grinding in a laboratory mill, sieving through a sieve, thorough mixing and conditioning. The certified values of moisture, nitrogen, protein, fat mass fraction for the sample № 1 were accordingly 4,5 %, 14,74 %, 92,1 %, 7,9 %. The same values in the same sequence were 6,3 %, 12,21 %, 76,3 %, 23,8 %.The procedure of lyophilisation was developed for production of reference materials for composition of boiled and freeze-dried poultry meat. The usage of this lyophilisation system allowed to ensure a RM expiration date of six months at ambient temperature of (7±3) °C and relative humidity no more than 60 %. The Reference Materials for composition of boiled and freeze-dried poultry meat was added into Register of certified RMs under № GSO 11276-2019 by the results.

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