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Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Perlite is a vitreous rock formed by rapid cooling of volcanic eruptive acidic lava. It is a very important non-metallic mineral, because of its brittleness, light weight, rapid expansion on heating, and other excellent characteristics, and is widely used in construction, water treatment, agriculture and other fields. However, according to the International Database for Certified Reference Materials ( COMAR), there is no reference material for perlite composition analysis at home and abroad. So, in order to meet the research needs of perlite, it is necessary to develop one. OBJECTIVES: To develop a reference material for composition analysis of perlite. The reference material can basically cover the chemical composition needed by the market. METHODS: Perlite samples were collected from Shangcheng County, Henan Province. The collected samples were dried and picked out, the bulk ore was crushed and ground in a ball mill for 40h, then the samples were coarse crushed and discharged, and the debris was removed by 1mm sieve. The samples were dried at 105℃ for 24h, dehydrated and inactivated. After drying, the samples were crushed in a grinder containing high -alumina ceramic balls, and the grinding time was determined by the time required to meet the particle size requirements of the first class standard substance. The processed samples were stored temporarily in polyethylene plastic vats under constant temperature and clean conditions, then sub-packed at 70g per bottle for test. Random samples were taken for homogeneity and stability tests. Through nine collaborative laboratories, more targeted valuation methods such as the gravimetric method, volumetric method, inductively coupled plasma - mass spectrometry, and inductively coupled plasma-optical emission spectrometry were used to ensure the accuracy of the perlite valued components. RESULTS: Fifteen items of 60 components were tested for uniformity and stability, including Ag, As, B, Ba, Be, Bi, Cd, Co, Cr, Cs, Cu, Ga, Hf, Hg, In, Li, Mo, Nb, Ni, Pb, Rb, Sb, Sc, Sn, Sr, Ta, Th, U, V, W, Zn, Zr, SiO2, Al2O3, TFe2O3, FeO, MgO, CaO, Na2O, K2O, MnO, TiO2, P2O5, LOI, TC, and rare earth elements. The RSD of most of the components was less than 3%, and the F value of the variance test was less than the critical value [F0. 05 (29,60) = 1. 65], indicating that the homogeneity of the reference material was good. During the stability inspection period, there was no significant difference in the content of the 60 components, indicating that the reference material was stable. The data were processed in accordance with General and Statistical Principles for Characterization of Reference Materials and outlier tests were performed using the Grubbs and Dixon methods. According to statistics, there were 2500 original data of perlite reference material, and 68 outliers were eliminated, with an elimination rate of 2. 7%. The standard value and uncertainty of the certified reference material for perlite composition analysis were determined by statistical processing of the constant value test data. The normal distribution of the mean data set was tested by the method of Shapiro-wilk, and the test results were all normal distribution. The final values were 63 components, covering major, trace, and all rare earth elements. The contents of three major components MgO, CaO and TFe2O3 were all less than 1%, which formed a gradient with the existing silicate reference material content. CONCLUSIONS: The certified reference material for perlite composition analysis developed in this paper has met the requirements of Technical Norm of Primary Reference Material ( JJF1006—94 ) by processing, crushing, homogeneity and stability test of the candidate. The test for uniformity and stability adopts the same detection technology as the fixed value method, and the selected fixed value technology is suitable and accurate, which ensures the accuracy of the fixed value data. The development of perlite composition analysis standard material has enriched the series of China geological mineral composition analysis standard material, and its chemical composition is numerous, it provides important technical support for instrument calibration, analysis method verification, quality control and quantity traceability of modern analytical technology. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sandstone-type uranium deposits are important strategic mineral resource. Rapid and accurate analysis of uranium and thorium content is of great significance to the evaluation and comprehensive utilization of this type of deposit. At present, the analysis of uranium and thorium is mainly determined by acid dissolution and alkali fusion methods to decompose samples. For the open acid dissolution method, the decomposition is often incomplete, resulting in lower results. The alkali fusion process is lengthy, which is not conducive to rapid detection. In addition, the high content of iron elements in sandstone type uranium deposits interfere with the measurement of uranium and thorium. OBJECTIVES: To develop a method which can determine uranium and thorium in sandstone uranium deposits by inductively coupled plasma-optical emission spectrometry (ICP-OES) with microwave digestion. METHODS: The samples were treated by microwave digestion technology, EDTA and triethanolamine mixed solution were added to the hydrochloric acid extract as masking agents to form a complex with iron ions in the solution, which effectively eliminated the interference of coexisting elemental iron on the determination of uranium and thorium. The experiment optimized the analytical spectral lines of each element, compared the amount of masking agent to obtain the best conditions, and basically eliminated the spectral line interference of coexisting elements by using the interference correction coefficient method. RESULTS: The linear correlation coefficients of standard curves were greater than 0. 9995, and the detection limit of uranium and thorium were 0. 70μg / g, and 0. 58μg / g, respectively. The relative error of the determination results of reference materials was 1. 47% - 1. 82% and the relative standard deviation ( RSD, n = 12) was 1. 32%-1. 78%. CONCLUSIONS: The method is simple to operate, effectively masking the interference of iron on uranium and thorium, and can be used to accurately complete the simultaneous determination of uranium and thorium in sandstone-type uranium deposits. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Jiaotong University (Medical Science) is the property of Journal of Shanghai Jiaotong University (Medical Science) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Solid sampling technology applied in soil sample measurement has the limitation of sample size, and cannot be applied to the mainstream element analysis instrument. OBJECTIVES: To determine the trace elements by smashing soil samples to micron scale by high - speed grinding technology and under the action of a dispersant. METHODS: The ultra - fine grinding technology of soil samples was systematically studied. The sample was crushed to micron level in a few minutes in an ethanol medium. The prepared solid suspension was directly measured by ICP - MS, avoiding blockage of pneumatic atomizers. RESULTS: The determination of the reference material shows that the solid suspension still has interference when the particle size is 6. 8 p.m. By adding a small amount of hydrofluoric acid and nitric acid to modify the solid suspension, the solid particle size was reduced and thereby the impact of the sample size was reduced. The 13 trace elements of lithium , beryllium , vanadium , chromium , nickel , copper , zinc , rubidium , strontium , cadmium , cesium , barium and lead were successfully determined by ICP - MS. Accuracy experiment showed that the maximum relative error is 10. 5% ±3% and most of the elements have a relative error less than 5% . The precision experiment showed that most elements have a relative standard deviation (RSD) of less than 5%. CONCLUSIONS: The determination results meet the requirements of DZ/G 0130-2006 ‘Test of Geology and Mineral Resources Quality Management Standards ’ . [ABSTRACT FROM AUTHOR]

BACKGROUND: The reductive environment of uranium is the most important influencing factor of uranium mineralization. The study of various redox markers in interlayer oxidation bands is of great significance for finding interlayer oxidation zone sandstone-type uranium deposits.OBJECTIVES: The reduction experiments were carried out on reducing materials commonly found in sandstonetype uranium deposits such as ferrous,sulfide,pyrite,ilmenite,humic acid,biogas,and hydrogen. The reduction capacity of ferrous ion,sulfur ion,pyrite and other reduction factors at room temperature and pressure was studied.METHODS: By polarography and spectrophotometry experiments to determine U( Ⅵ) and U( Ⅳ) content respectively. Their reduction capacity was analyzed.RESULTS: Iron ion and sulfur ion had strong reducing properties,andhumic acid had certain reducing properties.Such as pyrite,ilmenite experiment in different acidity and sage green sandstone water soaking experiments showed that the soaked solution of gray-green sandstone contained a certain amount of ferrous ions,and there was no sulfur ion.CONCLUSIONS: These ferrous ions were the main reason for the strong reducibility of gray-green sandstone.It also indicated that the gray-green sandstone was one of the most important factors in the subsequent mineralization of sandstone type uranium deposit in Ordos area. [ABSTRACT FROM AUTHOR]