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Determination of Trace Impurities of Rare Earth Elements in High Purity Yttrium Oxide by ICPMS 被引量:2
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作者 刘晶磊 童迎东 章新泉 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第1期52-57,共6页
DeterminationofTraceImpuritiesofRareEarthElementsinHighPurityYttriumOxidebyICPMS¥LiuJinglei;TongYingdong;Zha... DeterminationofTraceImpuritiesofRareEarthElementsinHighPurityYttriumOxidebyICPMS¥LiuJinglei;TongYingdong;ZhangXinquan(Centreo... 展开更多
关键词 ICPMS High purity YTTRIUM OXIDE Determination of TRACE RARE earth element
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Determination of Non-Rare Earth Impurities in High Purity Lanthanum Oxide by Inductively Coupled Plasma Atomic Emission Spectrometry after HPLC Separation Using P507 Resin
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作者 江祖成 胡斌 +2 位作者 帅琴 秦永超 王雷 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第4期299-303,共5页
A new method for the determination of trace non rare earth elements (NREEs) impurities in high purity lanthanum oxide by HPLC combined with ICP AES is proposed. The chromatographic retention behaviors of matrix (La) a... A new method for the determination of trace non rare earth elements (NREEs) impurities in high purity lanthanum oxide by HPLC combined with ICP AES is proposed. The chromatographic retention behaviors of matrix (La) and NREEs were studied using 2 ethylhexyl hydrogen 2 ethylhexyl phosphonate (P507) chelating resin as the stationary phase and dilute nitric acid as the mobile phase. It is found that the use of pH 1.7 nitric acid enables effective elution of NREEs from HPLC column, but the lanthanum remains on the column. The experimental results show that a favorable separation between matrix lanthanum and NREEs can be obtained within 15 min. The method proposed is applied to the determination of 8 NREEs impurities in high purity La 2O 3. The recoveries of 8 NREEs are in the range of 90%~110%. 展开更多
关键词 RARE earths HPLC 2 ethylhexyl hydrogen 2 ethylhexylphosphonate (P507) ICP AES high purity LANTHANUM oxide non RARE earth IMPURITIES
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Quantification of trace amounts of impurities in high purity cobalt by high resolution inductively coupled plasma mass spectrometry 被引量:10
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作者 XIE Hualin HUANG Kelong +1 位作者 NIE Xidu TANG Yougen 《Rare Metals》 SCIE EI CAS CSCD 2007年第3期286-291,共6页
An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, A... An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pt, Au, and Pb) in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCl. The matrix effects because of the presence of excess HCl and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the deter- mination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits were 0.016-1.50 μg?g?1, the recovery ratios were 92.2%-111.2%, and the RSD was less than 3.6%. The method was accurate, quick, and convenient. It was applied to the determination of trace impurities in high purity cobalt with satisfactory results. 展开更多
关键词 高纯度钴 等离子体 光谱测定术 杂质跟踪 分辨率
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Quantification of Trace Amounts of Impurities in High Purity Cobalt by High Resolution Inductively Coupled Plasma Mass Spectrometry 被引量:3
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作者 Hua Lin XIE Xi Du NIE You Gen TANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1077-1080,共4页
An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, Sb... An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pt, Au and Pb in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCl. The matrix effects due to the presence of excess HCl and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination was tested and discussed. Correction for matrix effects, Sc, Rh and Bi were used as internal standards. The detection limits is 0.003-0.57 μg/g, the recovery ratio is 92.2%-111.2%, and the RSD is less than 3.6%. The method is accurate, quick and convenient. It has been applied to the determination of trace impurities in high purity cobalt with satisfactory results. 展开更多
关键词 高纯度钴 高分辨率感应耦合等离子体质谱分析 痕量杂质 基体效应 光谱干扰 内标
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Direct Determination of Trace Impurities in High Purity Zinc Oxide by High Resolution Inductively Coupled Plasma Mass Spectrometry 被引量:2
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作者 谢华林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第2期28-32,共5页
The determination of trace impurities in high purity zinc oxide by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) was investigated. To overcome some potentially problematic spectral interfere... The determination of trace impurities in high purity zinc oxide by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) was investigated. To overcome some potentially problematic spectral interference, measurements were acquired in both middle and high resolution modes. The matrix effects due to the presence of excess HCl and zinc were evaluated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits ranged from 0.02 μg/g to 6 μg/g depending on the elements.The experimental results for the determination of Na, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Mo, Cd, Sb and Pb in several high purity zinc oxide powders were presented. 展开更多
关键词 高纯氧化锌 微量杂质 含量测定 高分辨率感应耦合等离子体质谱学 光谱干扰 微波溶解
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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
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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 沉淀剂 亚硝基萘酚 基质分离 ICP-AES 氧化钴 测定
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Rapid accuracy determining DNA purity and concentration in heavy oils by spectrophotometry methods
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作者 YunYang Wan HongMei Mu +4 位作者 Na Luo JianPing Yang Yan Tian Ning Hong HaiLiang Dong 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3394-3399,共6页
DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstr... DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstream molecular biology research. In this study, three different spectrophotometry methods, BPM, NDTT and NPMTTZ were compared for their performance in determining DNA concentration and purity in 32 oil samples, and molecule methods like quantitative real-time PCR (qPCR) and high-throughput sequence were also performed to help assess the accuracy of the three methods in determining DNA concentration and purity. For ordinary heavy oil (OHO), extra heavy oil (EHO) and super heavy oil (SHO), the characteristics of high viscosity (η), density (ρ) and resin plus asphaltene content will affect the DNA extraction and UV determination. The DNA concentration was decreased as density increased: OHO (11.46 ± 18.34 ng/μL), EHO (6.68 ± 9.67 ng/μL) and SHO (6.20 ± 7.83 ng/μL), and the DNA purity was on the reverse: OHO (1.31 ± 0.27), EHO (1.54 ± 0.20), and SHO (1.83 ± 0.32). The results suggest that spectrophotometry such as BPM and NPMTTZ are qualitatively favorite methods as the quick non-consumable methods in determining DNA concentration and purity of medium oil and heavy oil. 展开更多
关键词 Heavy oil DNA concentration DNA purity SPECTROPHOTOMETRY qPCR
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Visualizing and witnessing first-order coherence,Bell nonlocality and purity by using a quantum steering ellipsoid in the non-inertial frame
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作者 杨欢 邢玲玲 +3 位作者 杜明明 孔敏 张刚 叶柳 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期210-218,共9页
A quantum steering ellipsoid(QSE)is a visual characterization for bipartite qubit systems,and it is also a novel avenue for describing and detecting quantum correlations.Herein,by using a QSE,we visualize and witness ... A quantum steering ellipsoid(QSE)is a visual characterization for bipartite qubit systems,and it is also a novel avenue for describing and detecting quantum correlations.Herein,by using a QSE,we visualize and witness the first-order coherence(FOC),Bell nonlocality(BN)and purity under non-inertial frames.Also,the collective influences of the depolarizing channel and the non-coherence-generating channel(NCGC)on the FOC,BN and purity are investigated in the QSE formalism.The results reveal that the distance from the center of the QSE to the center of the Bloch sphere visualizes the FOC of a bipartite system,the lengths of the QSE semiaxis visualize the BN,and the QSE's shape and position dominate the purity of the system.One can capture the FOC,BN and purity via the shape and position of the QSE in the non-inertial frame.The depolarizing channel(the NCGC)gives rise to the shrinking and degradation(the periodical oscillation)of the QSE.One can use these traits to visually characterize and detect the FOC,BN and purity under the influence of external noise.Of particular note is that the condition for the QSE to achieve the center of the Bloch sphere cannot be influenced by the depolarizing channel and the NCGC.The characterization shows that the conditions for the disappearance of the FOC are invariant under the additional influences of the depolarizing channel and NCGC. 展开更多
关键词 quantum steering ellipsoid first-order coherence Bell-nonlocality purity
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Effect of Al addition on corrosion behavior of high-purity Mg in terms of processing history
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作者 Sang Kyu Woo Byeong-Chan Suh +1 位作者 Ha Sik Kim Chang Dong Yim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第3期851-868,共18页
In this study,the effects of Al addition on the corrosion behavior of pure Mg with controlled impurity contents were systematically analyzed according to the processing history.The results revealed that the corrosion ... In this study,the effects of Al addition on the corrosion behavior of pure Mg with controlled impurity contents were systematically analyzed according to the processing history.The results revealed that the corrosion behavior of high-purity Mg-Al alloys is strongly related to changes in the microstructure,including theβphase and Al-Mn or Al-Fe phases,and the protectiveness of the surface film according to the Al content and processing history.In the as-cast alloys,the corrosion rate increased due to the increase ofβphase as the Al content increased,but in the as-extruded alloys,the corrosion rate,which was high due to intermetallic compounds caused by impurities in the low Al alloy,decreased as the Al content increased,and then increased again.This is due to the combined effect of the increase of theβphase and decrease of the impurity effect,and the increase of the dissolved Al content.The results suggest that it is necessary to analyze the effect of alloying elements on the corrosion behavior of pure Mg with information concerning the impurity content and processing history. 展开更多
关键词 Mg High purity Mg-Al alloys Processing history Micro-galvanic Surface film
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Accurate quantification of TiO_(2)(B)'s phase purity via Raman spectroscopy
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作者 Jiamiao Ran Hui Liu +8 位作者 Hongliang Dong Peng Gao Haowei Cheng Jianing Xu Hailun Wang Zixing Wang Qingfeng Fu Jiaxu Yan Jilei Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第5期1371-1379,共9页
Bronze phase titanium dioxide(TiO_(2)(B))could be a promising high-power anode for lithium ion battery.However,TiO_(2)(B)is a metastable material,so the as-synthesized samples are inevitably accompanied by the existen... Bronze phase titanium dioxide(TiO_(2)(B))could be a promising high-power anode for lithium ion battery.However,TiO_(2)(B)is a metastable material,so the as-synthesized samples are inevitably accompanied by the existence of anatase phases.It has been found that the TiO_(2)(B)'s purity is positively correlated with its electrochemical performance.Herein,we have established an accurate quantification of the TiO_(2)(B)/anatase ratio,by figuring out the function between the purity of TiO_(2)(B)phase in the high purity range and its Raman spectra features in combination of the calibration by the synchrotron radiation X-ray diffraction(XRD).Compared with the time-consuming electrochemical method,the rapid,sensitive and non-destructive features of Raman spectroscopy have made it a promising candidate for determining the purity of TiO_(2)(B).Further,the correlations developed in this work should be instructive in synthesizing pure TiO_(2)(B)and furthermore optimizing its electrochemical charge storage properties. 展开更多
关键词 TiO_(2)(B) Phase purity Raman spectroscopy Synchrotron XRD Charge storage properties
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Preparation of High-purity Sodium Tungstate from Low-grade Tung-sten-concentrate with a High Content of Calcium and Other Impurities
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作者 孙培梅 陈洲溪 +3 位作者 李洪桂 李运姣 梁永堂 陈树翘 《Rare Metals》 SCIE EI CAS CSCD 1996年第2期116-122,共7页
PreparationofHigh-puritySodiumTungstatefromLow-gradeTung-sten-concentratewithaHighContentofCalciumandOtherIm... PreparationofHigh-puritySodiumTungstatefromLow-gradeTung-sten-concentratewithaHighContentofCalciumandOtherImpuritiesSunPeimei... 展开更多
关键词 LOW-GRADE tungsten-concentrate Mechanical ACTIVATING causticdecomposition Ion exchange HIGH-purity SODIUM TUNGSTATE
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大中小学英语“课程思政”一体化PURITY模式的构建研究——基于教师专业学习共同体视角
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作者 王勤梅 张克会 《大学(研究与管理)》 2023年第3期142-147,共6页
大中小学“课程思政”一体化建设越来越受到学界的关注,英语学科作为“大思政”格局中重要的一部分,对学生意识形态和价值观的引领起着重要的作用。本研究在当前大中小学课程思政一体化研究的基础上,从教师专业学习共同体视角,构建了大... 大中小学“课程思政”一体化建设越来越受到学界的关注,英语学科作为“大思政”格局中重要的一部分,对学生意识形态和价值观的引领起着重要的作用。本研究在当前大中小学课程思政一体化研究的基础上,从教师专业学习共同体视角,构建了大中小学英语“课程思政”一体化PURITY模式,该模式基于教师专业学习共同体的支持性条件、共同体成员、目标、专业运用与实践四个维度来实现。通过两学期的实践探索发现,PURITY模式有效地达成了理论—实践融合的目标,增强了大中小学英语教师的交流与合作,节约了资源的利用,促进大中小学英语教师专业发展。 展开更多
关键词 大中小学“课程思政” 一体化 purity模式 专业学习共同体
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关于高纯石英原料矿石地质学评价方法的探讨
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作者 张亮 刘磊 +2 位作者 朱黎宽 王红杰 原垭斌 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第4期1311-1326,共16页
高纯石英资源是一种重要的战略性资源。本文结合高纯石英成矿地质特征及其对后期选矿提纯、材料加工等的影响,系统总结了高纯石英原料中杂质的赋存状态、形成机理以及评价方法等,得出:(1)可以作为高纯石英原料的潜在岩石类型有花岗伟晶... 高纯石英资源是一种重要的战略性资源。本文结合高纯石英成矿地质特征及其对后期选矿提纯、材料加工等的影响,系统总结了高纯石英原料中杂质的赋存状态、形成机理以及评价方法等,得出:(1)可以作为高纯石英原料的潜在岩石类型有花岗伟晶岩(包括不含暗色矿物的伟晶状花岗岩)、脉石英以及水晶,岩浆演化晚期的伟晶状花岗岩-伟晶岩早期阶段的NYF型花岗伟晶岩结晶形成的石英纯度更高,后期适当的变形变质作用更有利于高纯石英矿床的形成。高纯石英原料矿石中石英矿物呈现无色透明至半透明,矿物构造裂隙少,伟晶岩型矿石矿物组成通常为石英、钠长石、条纹长石、白云母等,黑云母等暗色矿物含量极少,基本不见锂辉石、独居石等稀有金属矿物和电气石、萤石等含挥发分矿物。(2)影响高纯石英的主要地质因素包括脉石矿物及晶界杂质、包裹体、晶格杂质等。其中包裹体类型、数量和尺寸是包裹体评价的关键指标,天然石英矿物中的气液两相包裹体、矿物包裹体和<10μm包裹体应尽量少;Al和Ti是晶格杂质元素评价标志性元素,通常要求天然石英矿物中Al<50×10-6和Ti<10×10-6。(3)建议按照手标本特征-石英矿物特征-石英中包裹体特征-晶格元素赋存状态及含量的顺序,从宏观到微观,综合借助光学显微镜、扫描电子显微镜(SEM)、阴极荧光光谱分析系统(SEM-CL)、激光剥蚀电感耦合等离子质谱仪(LA-ICP-MS)等开展地质学评价和研究工作。 展开更多
关键词 高纯石英 矿石特征 包裹体 晶格杂质元素 评价方法
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高光学纯度乳酸菌株的筛选及发酵性能研究
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作者 刘兰 李鹏 +1 位作者 王通 黄筱萍 《食品与发酵工业》 CAS CSCD 北大核心 2024年第7期24-31,共8页
从不同地区的土壤、泡菜中分离筛选出了2株高光学纯度D-乳酸菌株和2株高光学纯度L-乳酸菌株。通过形态学观察、生理生化鉴定和16S rDNA序列分析,确定L-乳酸产生菌HA7-5菌株为屎肠球菌(Enterococcus faecium),HJ57菌株为格氏乳球菌(Lacto... 从不同地区的土壤、泡菜中分离筛选出了2株高光学纯度D-乳酸菌株和2株高光学纯度L-乳酸菌株。通过形态学观察、生理生化鉴定和16S rDNA序列分析,确定L-乳酸产生菌HA7-5菌株为屎肠球菌(Enterococcus faecium),HJ57菌株为格氏乳球菌(Lactococcus garvieae);D-乳酸产生菌HB49-2菌株为德氏乳杆菌(Lactobacillus delbrueckii),HL64-1菌株为假肠膜明串株菌(Leuconostoc pseudomesenteroides)。经摇瓶发酵产酸培养,菌株HA7-5和HJ57发酵产L-乳酸分别达71.83 g/L和31.89 g/L;菌株HB49-2和HL64-1发酵产D-乳酸分别达73.14 g/L和62.04 g/L,且菌株HL64-1发酵周期仅为24 h,产酸速率快,平均产酸速率为2.58 g/(L·h)。D体和L体光学纯度均达99.8%(ee)以上。以上菌株均为产高光学纯度L-或D-乳酸野生型菌株,可作为后期诱变育种的出发菌株,进行菌株改良及发酵性能提升的研究。 展开更多
关键词 乳酸菌 分离 鉴定 高光学纯度乳酸 发酵
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基于红外光谱与多种预处理组合的柴油纯度检测方法
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作者 周围 李安吉 +3 位作者 俞铁铖 尹冉 赵丽娟 赵美琪 《精细石油化工》 CAS 2024年第1期32-37,共6页
利用红外光谱技术采集51种不同体积分数的柴油光谱数据,采用主成分马氏距离法剔除异常样本,通过71种预处理组合及偏最小二乘法建立了柴油纯度性质模型。结果表明:合理预处理后的建模效果明显优于未经预处理的效果,预测均方根误差(RMSEP... 利用红外光谱技术采集51种不同体积分数的柴油光谱数据,采用主成分马氏距离法剔除异常样本,通过71种预处理组合及偏最小二乘法建立了柴油纯度性质模型。结果表明:合理预处理后的建模效果明显优于未经预处理的效果,预测均方根误差(RMSEP)降到了0.0400以下,相关系数(R_(p))达到了0.9900以上,且预处理组合方法的顺序不同,其建模效果即模型评价指标RMSEP、R_(p)也不同;1stderivative+SNV、1^(st) derivative+SNV+center、1^(st) derivative+center+SNV、center+1stderivative+SNV这4种预处理组合方法的模型预测效果最好,RMSEP可达0.0187,R_(p)可达0.9978,可适用于柴油纯度光谱数据的处理,实现柴油纯度的检测。 展开更多
关键词 柴油纯度 红外光谱 预处理组合 偏最小二乘
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高纯液氨中痕量油分检测方法
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作者 姜阳 《低温与特气》 CAS 2024年第2期44-47,共4页
介绍了气体中油分检测的多种方法,比较了各方法的原理与适用范围。根据液氨中油分杂质的特性,提出了用总有机碳分析仪对痕量油分进行分析的新方法,该方法检出限为0.0015 mg/kg。液氨中有机碳为0.01~1.0 mg/kg,相对标准偏差为0.29%~4.40%... 介绍了气体中油分检测的多种方法,比较了各方法的原理与适用范围。根据液氨中油分杂质的特性,提出了用总有机碳分析仪对痕量油分进行分析的新方法,该方法检出限为0.0015 mg/kg。液氨中有机碳为0.01~1.0 mg/kg,相对标准偏差为0.29%~4.40%,加标回收率为99.64%~107.14%,可以实现高纯液氨中痕量油分的准确定量。 展开更多
关键词 高纯液氨 油分 总有机碳 TOC
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高纯溶剂应用及行业高质量发展展望
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作者 全灿 《化学试剂》 CAS 2024年第1期1-7,共7页
化学工业是国民经济的基干产业,在区域经济的许多部门发挥着至关重要的作用。高纯溶剂作为基础化工材料,服务国民经济主战场,与人们生产生活密接相关。绿色溶剂助力实现人类命运共同体和联合国可持续发展目标。首先介绍高纯溶剂的国内... 化学工业是国民经济的基干产业,在区域经济的许多部门发挥着至关重要的作用。高纯溶剂作为基础化工材料,服务国民经济主战场,与人们生产生活密接相关。绿色溶剂助力实现人类命运共同体和联合国可持续发展目标。首先介绍高纯溶剂的国内外市场应用,国际高纯溶剂行业发展趋势、市场以及增长动能,在此基础上,应我国高质量发展需求,展望高纯溶剂如何服务我国国民经济主战场,如何服务国家重大需求,重点介绍高纯溶剂标准物质研制以建立溯源性、电子级高纯溶剂标准化满足半导体行业重大需求以及生物基溶剂满足行业绿色环保发展需求。 展开更多
关键词 高纯溶剂 市场 应用 高质量发展 标准物质 电子级 生物基溶剂
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响应面法优化魔芋葡甘聚糖的纯化工艺
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作者 包芮宁 吴卫国 +1 位作者 廖卢艳 王燕 《食品工业科技》 CAS 北大核心 2024年第7期210-216,共7页
魔芋粉中脂肪、蛋白质等限制魔芋葡甘聚糖的应用,因此对魔芋粉进行纯化处理得到纯度更高的魔芋葡甘聚糖应用于食品、药品等产业。本研究采用乙醇作为溶剂,对利用超声波辅助纯化魔芋粉的工艺进行优化。经过单因素实验分析料液比、乙醇浓... 魔芋粉中脂肪、蛋白质等限制魔芋葡甘聚糖的应用,因此对魔芋粉进行纯化处理得到纯度更高的魔芋葡甘聚糖应用于食品、药品等产业。本研究采用乙醇作为溶剂,对利用超声波辅助纯化魔芋粉的工艺进行优化。经过单因素实验分析料液比、乙醇浓度、超声时间、超声功率、超声温度5个相关因素的显著性,选择料液比、乙醇浓度和超声时间为较显著的因子进行分析。而后通过响应面拟合模型对各相关因素进行优化,最终确定在料液比1:102(g/mL)、乙醇浓度73%、超声时间55 min、超声功率175 W、超声温度50℃条件下,魔芋葡甘聚糖含量为88.1%,与预测值相近,纯化工艺切实可行。利用红外光谱仪和X射线衍射仪测定优化前后样品结构,未发现明显差异。经该工艺纯化后的魔芋粉中魔芋葡甘聚糖含量明显高于未纯化魔芋粉,且结构受影响较小,本文旨在为魔芋葡甘聚糖的高效开发和利用提供理论依据。 展开更多
关键词 响应面 超声 魔芋葡甘聚糖 纯度
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提高溶解浆纯度的研究进展
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作者 张兰昊 于冬梅 +1 位作者 陈业红 吴朝军 《中国造纸》 CAS 北大核心 2024年第1期57-65,共9页
溶解浆是α-纤维素含量高于90%的漂白浆,是多种纤维素工业产品的制造原料,而纤维素工业产品不仅是制药、食品、化妆品和其他工业领域的重要添加剂之一,还可用来制作手机屏幕等电子产品零件,这些均对溶解浆的纯度和质量提出了更高的要求... 溶解浆是α-纤维素含量高于90%的漂白浆,是多种纤维素工业产品的制造原料,而纤维素工业产品不仅是制药、食品、化妆品和其他工业领域的重要添加剂之一,还可用来制作手机屏幕等电子产品零件,这些均对溶解浆的纯度和质量提出了更高的要求。溶解浆的纯化是通过提高α-纤维素含量、去除溶解浆中半纤维素、木质素-碳水化合物(LCC)等杂质来实现的。本文对溶解浆的纯化方法进行了综述,对比分析了生物纯化法、化学纯化法及组合纯化法等;并剖析了各种纯化技术的机理;归纳了各种纯化溶解浆技术的优缺点;提出了制备高纯度溶解浆的研究方向和思路。 展开更多
关键词 溶解浆 α-纤维素含量 高纯度 纯化方法
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基于黏性蒸馏-气相分离的冶金级粗碲提纯方法
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作者 黄大鑫 蒋文龙 +2 位作者 徐宝强 查国正 杨斌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第3期1037-1048,共12页
开发一种基于黏性蒸馏-气相分离的高纯碲材料制备方法。通过调节冷凝器结构和冷凝温度,达到黏性蒸馏、控制碲优势冷凝区的目的,使挥发性差的物质留在残留物中,而硒在气相中与碲分离,实现冶金级粗碲的提纯。研究饱和蒸气压、碲分子平均... 开发一种基于黏性蒸馏-气相分离的高纯碲材料制备方法。通过调节冷凝器结构和冷凝温度,达到黏性蒸馏、控制碲优势冷凝区的目的,使挥发性差的物质留在残留物中,而硒在气相中与碲分离,实现冶金级粗碲的提纯。研究饱和蒸气压、碲分子平均自由程、不同冷凝位置的杂质分布特征以及冷凝物形貌。500 g级的实验结果表明,在5 Pa、773 K和90 min的最佳实验条件下,碲的直收率为83.40%,纯度高于99.9996%,碲优势冷凝区冷凝物中硒含量降低至2.76×10^(-4)%(质量分数)。 展开更多
关键词 高纯碲 除硒 提纯 平均自由程 优势冷凝区
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