期刊文献+
共找到17篇文章
< 1 >
每页显示 20 50 100
Determination of trace impurity elements in MnZn ferrite powder by direct current glow discharge mass spectrometry 被引量:4
1
作者 FU Liang MA Jun-cai SHI Shu-yun 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第7期1590-1597,共8页
An analytical method for the determination of 26 impurity elements (such as Li, Be, Na, Mg, Al, Si, P, S, K, Ca, Sc, Ti, V, Cr, Co, Ni, Ga, Ge, Y, Nb, Mo, Ag, Cd, Sb, W and Pb) in MnZn ferrite powder by direct curre... An analytical method for the determination of 26 impurity elements (such as Li, Be, Na, Mg, Al, Si, P, S, K, Ca, Sc, Ti, V, Cr, Co, Ni, Ga, Ge, Y, Nb, Mo, Ag, Cd, Sb, W and Pb) in MnZn ferrite powder by direct current glow discharge mass spectrometry (GD-MS) was established. MnZn ferrite powder was mixed with copper powder, used as a conductor, and pressed. The effects of MnZn ferrite powder preparation conditions and glow discharge parameters for the sensitivity and stability of signal analysis were investigated. By determining the choice of isotope and the application of the mass resolutions of 4000 (MR, medium resolution) and 10000 (HR, high resolution), mass spectral interference was eliminated. The contents of impurity elements in MnZn ferrite powder was calculated by subtraction after normalizing the total signal of Mn, Zn, Fe, O and Cu. The results showed that the detection limit of 26 kinds of impurity elements was between 0.002 and 0.57 μg/g, and the relative standard deviation (RSD) was between 3.33% and 32.35%. The accuracy of this method was verified by the ICP-MS. The method was simple and practical, which is applied to the determination of impurity elements in MnZn ferrite powder. 展开更多
关键词 MnZn ferrite powder glow discharge mass spectrometry impurity elements copper powder
在线阅读 下载PDF
Determination of impurity elements in MnZn ferrites by inductively coupled plasma mass spectrometry 被引量:3
2
作者 张萍 符靓 +1 位作者 马俊才 唐有根 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期37-42,共6页
An inductively coupled plasma mass spectrometry(ICP-MS) method was developed for the determination of Na, Mg, Al,K, Ca, Ti, Cr, Co, Ni, Cu, Ga, As, Mo, Ag, Cd and Pb in MnZn ferrites. The sample was digested by HNO3+H... An inductively coupled plasma mass spectrometry(ICP-MS) method was developed for the determination of Na, Mg, Al,K, Ca, Ti, Cr, Co, Ni, Cu, Ga, As, Mo, Ag, Cd and Pb in MnZn ferrites. The sample was digested by HNO3+HCl with microwave digestion followed by dilution with ultrapure water, then the above 16 impurity elements in the solution were analyzed directly by ICP-MS. The impurity elements were introduced by the helium gas or hydrogen gas into the octopole reaction system(ORS) to eliminate the polyatomic interferences caused by the high salty matrixes. The matrix effect was minimized through matrix matching,and Be, Y and Rh were used as internal standard elements. The working parameters of the instrument were optimized. The results show that the method has good precision and high accuracy. The detection limits for the investigated elements are in the range of0.9-37.5 ng/L, the relative standard deviation of each element is within 1.1%-4.8%, and the recovery of each element is 90%-108%. 展开更多
关键词 inductively coupled plasma mass spectrometry(ICP-MS) MnZn ferrites octopole reaction system(ORS) impurity elements
在线阅读 下载PDF
Analysis of Impurity Density in the Structure of Arsenopyrite of the Panimba Deposit
3
作者 Victor V.Onufrienok Maarten A.T.M.Broekmans 《矿物学报》 CAS CSCD 北大核心 2013年第S1期94-94,共1页
Based on comprehensive analysis of the crystal structure, chemical and phase composition of natural arsenopyrite of the "Panimba" deposit (Krasnoyarsk region), an analytical expression for calculating the im... Based on comprehensive analysis of the crystal structure, chemical and phase composition of natural arsenopyrite of the "Panimba" deposit (Krasnoyarsk region), an analytical expression for calculating the impurity density in structure of minerals type of marcasite are received. 展开更多
关键词 gold impurity DENSITY ARSENOPYRITE chemical compound crystal STRUCTURE theoretical CALCULATIONS
在线阅读 下载PDF
IMPURITY EFFECTS ON INTERFACE STABILITY
4
作者 Zhang Ying Dai Xianqi Ji YuanmingPhysics Department, Henan Normal University Xinxiang Henan 453002Pingyuan University, Xinxiang Henan 453002 《原子与分子物理学报》 CAS CSCD 北大核心 1998年第S1期249-250,共2页
Thequantum-mechanicaltheoryofsolidinterfaceisanexpandingbranchofsurfacephysics.Thepropertiesofmetal-semicond... Thequantum-mechanicaltheoryofsolidinterfaceisanexpandingbranchofsurfacephysics.Thepropertiesofmetal-semiconductorinterfaceare... 展开更多
关键词 Green FUNCTION INTERFACE ENERGY impurity
在线阅读 下载PDF
An evaluation of the influence of impurity concentration and composition in concrete on activation and radiation dose in the reactor facility
5
作者 Jae Hyun KIM Myeong Hyeon WOO +1 位作者 Chang Ho SHIN Jong Kyung KIM 《辐射防护》 CAS CSCD 北大核心 2020年第6期486-490,共5页
The content analysis of radioactive waste and radiation dose evaluation is considered as one of the important factors in the reactor facility design.This kind of buildings consists of the concrete for the most part an... The content analysis of radioactive waste and radiation dose evaluation is considered as one of the important factors in the reactor facility design.This kind of buildings consists of the concrete for the most part and uses it as the structure and shield of the building.Generally,the concrete has impurities such as cobalt,europium,nickel,and cesium with specific content depending on the production method or manufacturing company.Dominant radioactive nuclides generated from the fundamental components of concrete are considered that it is less contributed to the radiation dose because they are beta decay nuclides in general.Thus,impurities of irradiated concrete in the reactor facilities,are considered occasionally an important evaluation factor for induced activity.In this study,the influence on the activation of impurities in concrete was evaluated from the radiation dose and induced activity calculations.The calculation was evaluated at the bio-shield which is one of the areas with the highest neutron irradiation among the concrete structure in the reactor facility.The results show that radioactive nuclides with gamma decay were produced in these impurities.Moreover,the radiation dose of concrete with impurities was higher than concrete without impurities.The increased radiation dose was quantified through the content of impurities. 展开更多
关键词 radiation dose CONCRETE impurity activation analysis
在线阅读 下载PDF
乙嘧酚磺酸酯中杂质的GC-MS分析 被引量:2
6
作者 宁艳利 张皋 赵效文 《分析测试学报》 CAS CSCD 北大核心 2008年第S1期263-265,269,共4页
The structure of bupirimate was identified by using MS and NMR.The structures of 10 impurities were identified by using GC-MS.The method provides a powerful tool for structure analysis special in complex samples.
关键词 bupirimate IMPURITIES structural IDENTIFY MS NMR GC-MS
在线阅读 下载PDF
ICP-MS法分析过氧化氢、硝酸、硫酸中的金属杂质 被引量:4
7
作者 黄曜 黄郁芳 《质谱学报》 EI CAS CSCD 2005年第z1期15-16,共2页
Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect trace metal impurities in reagents such as H2O2, HNO3and H2SO4. The limit of detection to metal elements can be down to 2-20 ng/L in H2O2 and HN... Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect trace metal impurities in reagents such as H2O2, HNO3and H2SO4. The limit of detection to metal elements can be down to 2-20 ng/L in H2O2 and HNO3 and 0.1-1.0 ng/L in H2SO4. 展开更多
关键词 inductively coupled plasma mass SPECTROMETRY (ICP-MS) metal IMPURITIES REAGENTS
在线阅读 下载PDF
辅酶Q10及其杂质结构鉴定 被引量:1
8
作者 宁艳利 王民昌 张皋 《分析测试学报》 CAS CSCD 北大核心 2008年第S1期266-269,共4页
The structure of coenzyme Q10 sample was identified by MS,IR and NMR.And the impurities were identified by HPLC-ESI MS.The unknown impurities were coenzyme Q10’s structure isomeride,Q9,Q11
关键词 identification COENZYME Q10 IMPURITIES STRUCTURAL IR NMR HPLC-ESI MS
在线阅读 下载PDF
SINA法生产己内酰胺工艺中杂质分析 被引量:6
9
作者 于广欣 高瑞娥 +1 位作者 肖光辉 王文生 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期302-303,共2页
  己内酰胺(CPL)工业生产方法有多种,由SINA公司开发的以甲苯为原料生产CPL中杂质种类多,与以苯为原料生产的己内酰胺产品中的杂质有很大的区别,并且杂质含量很低,且多数杂质物化性质与主成分相近,分离与检测都很困难[1,2].本文利用...   己内酰胺(CPL)工业生产方法有多种,由SINA公司开发的以甲苯为原料生产CPL中杂质种类多,与以苯为原料生产的己内酰胺产品中的杂质有很大的区别,并且杂质含量很低,且多数杂质物化性质与主成分相近,分离与检测都很困难[1,2].本文利用气相色谱-质谱联用仪对SINA法生产的己内酰胺进行了杂质的分析.…… 展开更多
关键词 SINA Process CAPROLACTAM impurity GC-MS Amidate
在线阅读 下载PDF
Simultaneous determination of seven impurities in high-purity cobalt oxide by ICP-AES after matrix separation using 1-nitroso-2-naphthol as a precipitant 被引量:1
10
作者 王艳 周春山 +1 位作者 段青兵 陈萍 《Journal of Central South University of Technology》 2002年第2期100-103,共4页
A method was developed for the simultaneous determination of seven trace impurities (Cd, Mn, Pb, Zn, Cu, Fe and Ni) in high purity cobalt oxide by ICP AES. The matrix effect was eliminated by preci pitation with 1 nit... A method was developed for the simultaneous determination of seven trace impurities (Cd, Mn, Pb, Zn, Cu, Fe and Ni) in high purity cobalt oxide by ICP AES. The matrix effect was eliminated by preci pitation with 1 nitroso 2 naphthol. The matrix effect of cobalt on the absorptions of trace impurities, the effects of reaction time, pH value, dosage of precipitant on the formation of cobalt 1 nitroso 2 naphthol complex, the effects of hydrochloric acid on the stability of this complex and masking of elements were studied. Recoveries of the impurities in spiked sample are from 90% to 110% with a precision of 1.1% 5.0% RSD. The detection limits of the seven elements are in the range of 0.01 0.24μg/g. The method can be applied to the analysis of high purity cobalt metal, cobalt oxide and other cobalt compounds. 展开更多
关键词 trace impurity high purity cobalt oxide matrix separation inductively coupled plasma atomic emission spectrometry (ICP AES)
在线阅读 下载PDF
EFFECT OF INTERSTITIAL IMPURITIES ON THE PHASETRANSFORMATION OF Ti-Al ALLOYS
11
作者 李文 支文 朴英锡 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共4页
应用固体与分子经验电子理论的平均晶胞和平均原子模型分析计算了间隙杂质对Ti-Al合金价电子结构和相变的影响。同时根据该理论的键能公式计算了间隙杂质影响下的键能、熔点和液相线的变化。据此解释了Ti-Al合金相变目前尚有争议的主要... 应用固体与分子经验电子理论的平均晶胞和平均原子模型分析计算了间隙杂质对Ti-Al合金价电子结构和相变的影响。同时根据该理论的键能公式计算了间隙杂质影响下的键能、熔点和液相线的变化。据此解释了Ti-Al合金相变目前尚有争议的主要实验结果。表明,间隙杂质提高了合金元素的原子杂阶,引起键结构呈严重的各向异性,阻碍了β→α相转变,导致中间成分相变的复杂性。间隙杂质也降低了熔点及高温液相线,采用近似处理由该理论可较好地计算其平均降低程度。 展开更多
关键词 TI-AL合金 相变 价电子结构 间隙杂质 EFFECT OF INTERSTITIAL IMPURITIES ON THE PHASE
在线阅读 下载PDF
指示稳定性的高效液相色谱方法和强制降解研究片剂型马西替坦中的杂质(英文)
12
作者 Narasimha S LAKKA Chandrasekar KUPPAN Parthasarathy RANGASAMY 《色谱》 CAS CSCD 北大核心 2019年第1期100-110,共11页
Macitentan (MAC) is a pulmonary arterial hypertension (PAH) drug marketed as a tablet and often has stability issues in the final dosage form. Quantitative determination of MAC and its associated impurities in tablet ... Macitentan (MAC) is a pulmonary arterial hypertension (PAH) drug marketed as a tablet and often has stability issues in the final dosage form. Quantitative determination of MAC and its associated impurities in tablet dosage form has not been previously reported. This study quantified impurities present in Macitentan tablets using a binary solvent-based gradient elution method using reversed phase-high performance liquid chromatography.The developed method w as validated per International Conference on Harmonization (ICH) guidelines and the drug product w as subjected to forced degradation studies to evaluate stability. The developed method efficiently separated the drug and impurities (48 min) w ithout interference from solvents,excipients,or other impurities. The developed method met all guidelines in all characteristics w ith recoveries ranging from 85%-115%,linearity w ith r 2≥0. 996 6,and substantial robustness. The stability-indicating nature of the method w as evaluated using stressed conditions (hydrolysis:1 N HCl at 80℃/15 min; 1 N NaOH at 25℃/45 min; humidity stress (90%relative humidity) at 25℃for 24 h,oxidation:at 6%(v/v) H2O2,80℃/15 min,thermolysis:at105℃/16 h and photolysis:UV light at 200 Wh/m2; Fluorescent light at 1. 2 million luxh). Forced degradation experiments show ed that the developed method w as effective for impurity profiling. All stressed samples w ere assayed and mass balance w as> 96%. Forced degradation results indicated that MAC tablets w ere sensitive to hydrolysis (acid and alkali) and thermal conditions. The developed method is suitable for both assay and impurity determination,w hich is applicable to the pharmaceutical industry. 展开更多
关键词 reverse phase-high performance liquid chromatography(RP-HPLC) STABILITY-INDICATING method forced degradation study binary solvent gradient ENDOTHELIN receptor antagonist(ERA) pulmonary ARTERIAL hypertension(PAH) macitentan(MAC) impurity profiling
在线阅读 下载PDF
LC-MS^n测定2-[[(2′-氰基联苯基)-4-基]甲基]氨基-3-硝基苯甲酸乙酯中的不纯物
13
作者 姚骏骅 《分析测试学报》 CAS CSCD 北大核心 2007年第z1期125-126,共2页
The impurities in ethyl-2-[[2′-cyanobiphenyl-4-yl] methyl] amino]-3-nitrobenzoate,an intermediate for synthesis of candesartan cilexiti,were detected by LC-MSn. The structural assignment of these impurities was carri... The impurities in ethyl-2-[[2′-cyanobiphenyl-4-yl] methyl] amino]-3-nitrobenzoate,an intermediate for synthesis of candesartan cilexiti,were detected by LC-MSn. The structural assignment of these impurities was carried out by LC-MSn using electrospray ionization source and an ion trap mass analyzer. The formation of the impurities was discussed. Also the fragmentation pathways of these compounds were studied. 展开更多
关键词 LC-MSn Ethyl-2-[[2′-cyanobiphenyl-4-yl] methyl] amino]-3-nitrobenzoate IMPURITIES Fragmentation pathways
在线阅读 下载PDF
同位素稀释质谱法对溶液中倍硫磷原药中杂质的质谱定性分析
14
作者 耿岳 傅利娟 +1 位作者 佟玲 李重九 《分析测试学报》 CAS CSCD 北大核心 2008年第S1期145-150,共6页
Fenthion is an organothiophosphate insecticide,which is a subset of the organophosphates.The analysis of impurities in the pesticide plays an important role in quality control,making a strong impact on the quality of ... Fenthion is an organothiophosphate insecticide,which is a subset of the organophosphates.The analysis of impurities in the pesticide plays an important role in quality control,making a strong impact on the quality of preparation,crops,non-target organisms,human health and the ecological environment.In this article,fenthion and 7 impurities were separated by GC and HPLC,and identified by using electron impact mass spectrometry(EI MS) and electrospray ionization mass spectrometry(ESI MS) methods.The fragmentation reactions of fenthion were further investigated in order to speculate the fragmentation structures of 展开更多
关键词 FENTHION IMPURITIES GC-MS GC-MS/MS HPLC-MS
在线阅读 下载PDF
Leaching behavior of zinc from crude zinc oxide dust in ammonia leaching 被引量:6
15
作者 JIANG Tao MENG Fei-yu +6 位作者 GAO Wei ZENG Yan SU Huan-huan LI Qian XU Bin YANG Yong-bin ZHONG Qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第9期2711-2723,共13页
Zinc extraction from crude zinc oxide(CZO)is beneficial to the full utilization of secondary resources and environmental protection.In this paper,a systematic investigation was carried out to study the leaching behavi... Zinc extraction from crude zinc oxide(CZO)is beneficial to the full utilization of secondary resources and environmental protection.In this paper,a systematic investigation was carried out to study the leaching behavior of CZO by using ammonia-ammonium carbonate solution.It was found that the maximum leaching rate of zinc from CZO dust was 95.7%under the conditions of[Zn]T:[NH 3]T:[CO_(3)^(2−)]=1:7.00:1.75,liquid to solid ratio 5:1,leaching temperature 30℃ and leaching time 60 min.Compared with pure zinc oxide(PZO)leaching,the CZO leaching required longer time and more leaching agents,which is caused by the Cd^(2+),Pb^(2+) and other metal cationic impurities in CZO.The metal cationic impurities dissolved in the leaching solution and combined with ammonium to form complexes,consuming leaching agents and affecting zinc leaching. 展开更多
关键词 crude zinc oxide dust ammonia leaching leaching behavior metal cationic impurities
在线阅读 下载PDF
Trace amounts of impurities in electrolytic manganese metal by sector field inductively coupled plasma mass spectrometry 被引量:3
16
作者 聂西度 梁逸曾 +1 位作者 唐有根 谢华林 《Journal of Central South University》 SCIE EI CAS 2013年第12期3385-3390,共6页
An analytical method, using sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) for rapid simultaneous determination of Be, Na, Mg, Si, Ca, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, As, Sn, Sb, Pb and Bi in e... An analytical method, using sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) for rapid simultaneous determination of Be, Na, Mg, Si, Ca, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, As, Sn, Sb, Pb and Bi in electrolytic manganese metal, was described. At the beginning, the samples were decomposed by HNO3 and H2504, and then analyzed by SF-ICP-MS. Most of the spectral interferences could be avoided by measuring in different mass resolution modes. The matrix effects due to the excess of sulfuric acid and Mn were evaluated. Correction of matrix effects was conducted by using the internal standard elements. The optimum condition for the determination was investigated and discussed. The detection limit is in the range of 0.001-0.169 gg/L. The current method is applied to the determination of trace impurities in electrolytic manganese metal. And experiments show that good results can be obtained much faster, more accurately and conveniently by current method. 展开更多
关键词 sector field inductively coupled plasma mass spectrometry electrolytic manganese IMPURITIES spectral interferences matrix effects
在线阅读 下载PDF
Electrode heating effects on preparation of Al-65V alloy
17
作者 WAN He-li XU Bao-qiang +3 位作者 LI Lan-jie YANG Bin WANG Li DAI Yong-nian 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期1-9,共9页
In this study,Al-65V alloy has been produced by electrode heating for 3−15 min.The impurities content,microstructure and the vanadium content of the alloy in the slag are investigated.The results indicate that differe... In this study,Al-65V alloy has been produced by electrode heating for 3−15 min.The impurities content,microstructure and the vanadium content of the alloy in the slag are investigated.The results indicate that different heating time shows obviously impacts not only on the impurities and microstructure of AlV alloy,but also on the vanadium recovery rate of slag.The impurities contents of C,O and N are 0.085%,0.022%and 0.036%,respectively,which meet the commercial standard when the electric heating time is controlled to 10 min,and the content of vanadium in slag is 0.18%. 展开更多
关键词 Al-65V alloy electrode heating impurities content microstructure
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部