期刊文献+
共找到276篇文章
< 1 2 14 >
每页显示 20 50 100
Preparation of high purity ruthenium nitrosyl nitrate from spent Ru-Zn/ZrO_(2)catalyst
1
作者 LIU Kai-ming QIU Yun-ren LI Yan 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3014-3023,共10页
Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying t... Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying to obtain ruthenium trichloride,nitrosation and hydrolysis to obtain ruthenium nitrosyl hydroxide,removing of K^(+)and Cl^(-),and neutralization with nitric acid.The effects of temperature,concentration,time and pH on the yield and purity of intermediates and final product were studied,and the optimum process conditions were obtained.The yield of ruthenium nitrosyl nitrate is 92%,the content of ruthenium in high purity product is 32.16%,and the content of Cl^(-)and K^(+)are much less than 0.005%.The reaction kinetics of ruthenium nitrosyl chloride to ruthenium nitrosyl hydroxide was studied.The reaction orders of Ru(NO)Cl_(3)at 40,55 and 70℃are 0.39,0.37 and 0.39,respectively,while those of KOH are 0.16,0.15 and 0.17,respectively.The activation energy is-2.33 k J/mol. 展开更多
关键词 ruthenium nitrosyl nitrate spent catalyst high purity utilization of wastes reaction kinetics
下载PDF
OAM mode purity improvement based on antenna array
2
作者 Dandan Liu Wei Wu +1 位作者 Liangqi Gui Tao Jiang 《Digital Communications and Networks》 SCIE CSCD 2024年第4期1145-1153,共9页
Orbital Angular Momentum(OAM)waves are characterized by helical wave fronts and orthogonality between different modes.Therefore,OAM waves have huge potential in improving wireless communications'channel capacity a... Orbital Angular Momentum(OAM)waves are characterized by helical wave fronts and orthogonality between different modes.Therefore,OAM waves have huge potential in improving wireless communications'channel capacity and radar imaging's resolution.Consequently,the generation and application of OAM waves have attracted a lot of attention.And many methods are proposed to generate OAM waves.Although antenna array is the most popular method of generating OAM waves,OAM waves generated by antenna array have redundant modes.However,all advantages of OAM waves are closely related to infinite OAM modes.Thus,to better apply OAM waves to wireless communications and radar,it is very important to reduce unnecessary OAM modes and improve the OAM mode purity.In order to improve the OAM mode purity,two combined antenna arrays composed of X direction antenna and Y direction antenna array are proposed in this paper.The X direction antenna array and the Y direction antenna array are supplied by the excitations with the same amplitude and fixed phase shift.The overall phase shift of the X direction antenna array isπ/2 more or less than that of the Y direction antenna array.The results of formulas and antenna models in CST show that the combined antenna arrays can generate OAM waves with less redundant modes in x component,y component and z component.Besides,the z component carries pure OAM modes. 展开更多
关键词 Orbital angular momentum Antenna array Theoretical formula OAM mode purity
下载PDF
Rapid accuracy determining DNA purity and concentration in heavy oils by spectrophotometry methods
3
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
下载PDF
Effect of Al addition on corrosion behavior of high-purity Mg in terms of processing history
4
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
下载PDF
Visualizing and witnessing first-order coherence,Bell nonlocality and purity by using a quantum steering ellipsoid in the non-inertial frame
5
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
原文传递
Accurate quantification of TiO_(2)(B)'s phase purity via Raman spectroscopy
6
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
下载PDF
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
7
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
下载PDF
Modification Behavior of Trace Rare Earth on Impurity Phases in Commercial Purity Aluminum 被引量:27
8
作者 傅高升 孙锋山 +2 位作者 任立英 陈文哲 钱匡武 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第1期61-66,共6页
Modifying effect and mechanism of trace rare earth on Fe(Si) rich impurity phases in commercial purity aluminum were studied with the aids of SEM, EDAX, TEM, etc. It is found that Ce rich mixed rare earth (RE) is an... Modifying effect and mechanism of trace rare earth on Fe(Si) rich impurity phases in commercial purity aluminum were studied with the aids of SEM, EDAX, TEM, etc. It is found that Ce rich mixed rare earth (RE) is an effective modifying agent, which makes the coarse Fe rich impurity phases transform into complex compounds of tiny, sphere/short stick form, thus improving mechanical properties of this material; its modifying mechanism is in that RE gathering in front of solid/liquid interface enters into the impurity phases, forming complex (AlFeSiRE) compounds; or is adsorbed in the impurity phases surface, impeding the growth of impurity phases; however, excessive RE will result in the increasing of RE compounds (secondary phases), and plasticity reduction of this material. Therefore, its addition amount should be less than 0 07% (mass fraction). 展开更多
关键词 rare earths commercial purity aluminum Fe rich impurity phases modification of impurity phases
下载PDF
Structure uniformity and limits of grain refinement of high purity aluminum during multi-directional forging process at room temperature 被引量:6
9
作者 朱庆丰 李磊 +3 位作者 班春燕 赵志浩 左玉波 崔建忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1301-1306,共6页
The effect of forging passes on the refinement of high purity aluminum during multi-forging was investigated. The attention was focused on the structure uniformity due to deformation uniformity and the grain refinemen... The effect of forging passes on the refinement of high purity aluminum during multi-forging was investigated. The attention was focused on the structure uniformity due to deformation uniformity and the grain refinement limitation with very high strains. The results show that the fine grain zone in the center of sample expands gradually with the increase of forging passes. When the forging passes reach 6, an X-shape fine grain zone is initially formed. With a further increase of the passes, this X-shape zone tends to spread the whole sample. Limitation in the structural refinement is observed with increasing strains during multi-forging process at the room temperature. The grains size in the center is refined to a certain size (110 μm as forging passes reach 12, and there is no further grain refinement in the center with increasing the forging passes to 24. However, the size of the coarse grains near the surface is continuously decreased with increasing the forging passes to 24. 展开更多
关键词 multi-directional forging high purity aluminum structure uniformity grain refinement
下载PDF
Effect of nano TiN/Ti refiner on as-cast and hot-working microstructure of commercial purity aluminum 被引量:4
10
作者 蔡思祺 李玉洁 +2 位作者 谌援 李欣蔚 薛丽红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期1890-1897,共8页
A novel type nano TiN/Ti composite grain refiner (TiN/Ti refiner) was prepared by high energy ball milling, and its effect on as-cast and hot-working microstructure of commercial purity aluminum (pure Al) was inve... A novel type nano TiN/Ti composite grain refiner (TiN/Ti refiner) was prepared by high energy ball milling, and its effect on as-cast and hot-working microstructure of commercial purity aluminum (pure Al) was investigated. The results show that TiN/Ti refiner exhibits excellent grain refining performances on pure Al. With an addition of 0.2% TiN/Ti refiner, the average grain size of pure Al decreases to 82 μm, which is smaller than that of pure Ti and Al 5Ti 1B master alloy as refiners. The microstructure of weld joint of pure Al with 0.1% TiN/Ti refiner is fine equiaxed grains and the hardness of weld joint is higher than that of the base metal. For pure Al with 40% cold deformation and recrystallization at 250 °C for 1.0 h, the grains of the sample added 0.1% Ti powder have an obvious grain growth behavior. In contrast, oriented grains caused by deformation have been eliminated, and there is no obvious grain growth in pure Al refined with 0.1% TiN/Ti refiner, indicating that nano TiN in the refiner inhibits the growth of grain during recrystallization. 展开更多
关键词 nano TiN/Ti composite grain refiner commercial purity aluminum grain refinement weld joint deformation and recrystallization
下载PDF
Signal-purity-spectrum-based colored deconvolution 被引量:3
11
作者 李国发 彭更新 +2 位作者 岳英 王万里 崔永福 《Applied Geophysics》 SCIE CSCD 2012年第3期333-340,362,共9页
Signal to noise ratio (SNR) and resolution are two important but contradictory characteristics used to evaluate the quality of seismic data. For relatively preserving SNR while enhancing resolution, the signal purit... Signal to noise ratio (SNR) and resolution are two important but contradictory characteristics used to evaluate the quality of seismic data. For relatively preserving SNR while enhancing resolution, the signal purity spectrum is introduced, estimated, and used to define the desired output amplitude spectrum after deconvolution. Since a real reflectivity series is blue rather than white, the effects of white reflectivity hypothesis on wavelets are experimentally analyzed and color compensation is applied after spectrum whitening. Experiments on real seismic data indicate that the cascade of the two processing stages can improve the ability of seismic data to delineate the geological details. 展开更多
关键词 signal purity spectrum SNR spectrum resolution spectrum whitening colorcompensation
下载PDF
Screening of SSR Core Primers for Purity Identification of Pepper(Capsicum) Hybrids 被引量:2
12
作者 管俊娇 黄清梅 +3 位作者 张鹏 马芙蓉 张惠 张建华 《Agricultural Science & Technology》 CAS 2015年第10期2155-2158,2230,共5页
[Objective] This study aimed to screen a set of SSR core primers suitable for purity identification of pepper (Capsicum) hybrids. [Method] DNA fingerprint of 100 pepper hybrids was analyzed using 17 SSR primers. [Re... [Objective] This study aimed to screen a set of SSR core primers suitable for purity identification of pepper (Capsicum) hybrids. [Method] DNA fingerprint of 100 pepper hybrids was analyzed using 17 SSR primers. [Result] According to the polymorphism and heterozygosity, Hpms1-214, Es395 and Hpmsl-5 were determined as three preferred core primers for purity identification of pepper hybrids. By using these three preferred core primers, 97 pepper hybrids (accounting for 97%) had heterozygous band pattern with at least one primer. Es330, Es363, Epms923, Es120 and Es64 were determined as candidate core primers for purity identification of pepper hybrids. Specific primers of 14 varieties were obtained, which could be used to further screen parent-complementary primers of each pepper hybrid. [Con- clusion] This study laid the foundation for constructing standard DNA fingerprints for purity identification of pepper hybrids. 展开更多
关键词 PEPPER SSR HYBRID purity identification Core primers
下载PDF
Identification of Genetic Purity of Bitter Gourd Hybrid by ISSR Markers 被引量:1
13
作者 陈龙正 徐海 +3 位作者 宋波 张慧 况媛媛 袁希汉 《Agricultural Science & Technology》 CAS 2015年第4期649-652,共4页
Objective] This study was conducted to verify the feasibiIity of ISSR marker for identifying genetic purity of bitter gourd hybrid, and thus to provide an effective method for seed purity test in production practices.... Objective] This study was conducted to verify the feasibiIity of ISSR marker for identifying genetic purity of bitter gourd hybrid, and thus to provide an effective method for seed purity test in production practices. [Method] The DNA fin-gerprints of a bitter gourd cuItivar Xiuyu 1 and its parents were analyzed using IS-SR marker with 91 primers. [Result] Two primers ISSR-845 and ISSR-891 which ampIified two DNA bands of 510 and 300 bp respectiveIy from F1 generation and its parents were screened out from 91 primers. ISSR-845 couId distinguish the male parent from F1 hybrid and the female parent, whiIe ISSR-891 couId distinguish the female parent inbred Iine from Xiuyu 1. Seed purity test with the specific markers gave the same resuIt with fiIed trials based on morphoIogical identification. [Conclu-sion] ISSR marker is an accurate, simpIe and effective method for seed purity test bitter gourd hybrid, and thus can be used in production practices. 展开更多
关键词 Bitter gourd ISSR marker purity test
下载PDF
Detection of Purity of Thai Hom Mali Rice by RAPD 被引量:1
14
作者 徐颖 《Agricultural Science & Technology》 CAS 2011年第11期1565-1568,共4页
[Objective] The aim was to establish more specific, sensitive, accurate and practical method to detect purity of Thai Hom Mali rice. [Method] RAPD method cooperated with two primers of KDML105 and RD15 was established... [Objective] The aim was to establish more specific, sensitive, accurate and practical method to detect purity of Thai Hom Mali rice. [Method] RAPD method cooperated with two primers of KDML105 and RD15 was established by feeling for the extraction methods of DNA, optimizing concentrations of the factors influencing the results of RAPD such as template DNA, Mg2+, random primer, dNTPs and Taq polymerase, and screening the random primers. [Result] The optimum RAPD reaction system was 25.0 μl in total volume, containing 4.0-32.0 ng/μl of template DNA, 200.0 μg/L random primer, 2.0 mmol/L Mg2+, 200.0 μmol/L dNTPs and 1.0 U of Taq enzyme. Then, the Thai Hom Mali rice and non-Thai Hom Mali rice can be distinguished according to the presence or absence of two DNA markers. [Conclusion] The RAPD technology can effectively cover the shortages of identifications by sense and boiling in water; in addition, it is simple, sensitive and low-cost, suitable to be used in routine tests. 展开更多
关键词 RAPD Thai Hom Mali Rice purity
下载PDF
A High Purity Integer-N Frequency Synthesizer in 0.35μm SiGe BiCMOS
15
作者 张健 李志强 +2 位作者 陈立强 陈普峰 张海英 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期655-659,共5页
An integer-N frequency synthesizer in 0.35μm SiGe BiCMOS is presented. By implementing different building blocks with different types of devices,a high purity frequency synthesizer with excellent spur and phase noise... An integer-N frequency synthesizer in 0.35μm SiGe BiCMOS is presented. By implementing different building blocks with different types of devices,a high purity frequency synthesizer with excellent spur and phase noise performance has been realized. All the building blocks are implemented with differential topology except for the off-chip loop filter. To further reduce the phase noise,bonding wires are used to form the resonator in the LC-VCO. The frequency synthesizer operates from 2.39 to 2.72GHz with output power of about 0dBm. The measured closed-loop phase noise is - 95dBc/Hz at 100kHz offset and - 116dBc/Hz at 1MHz offset from the carrier. The power level of the reference spur is less than - 72dBc. With a 3V power supply, the whole chip including the output buffers consumes 60mA. 展开更多
关键词 SiGe BiCMOS phase-locked loop high purity loop bandwidth
下载PDF
RAPD Appraisal of Purity of the Hybrid Rice SY63 被引量:1
16
作者 陈洪 钱前 +2 位作者 朱立煌 闵绍楷 陈美玲 《Developmental and Reproductive Biology》 1996年第2期60-66,共7页
使用纯度低或真实性差的杂交种子会给农业生产造成极大损失。然而杂交种子的纯度无法单纯从种子形态上鉴别.本文首次采用RAPD特异扩增谱带做为分子标记对水稻杂交种纯度进行了鉴定。汕优63杂交水稻种子由中国水稻研究所从某制种... 使用纯度低或真实性差的杂交种子会给农业生产造成极大损失。然而杂交种子的纯度无法单纯从种子形态上鉴别.本文首次采用RAPD特异扩增谱带做为分子标记对水稻杂交种纯度进行了鉴定。汕优63杂交水稻种子由中国水稻研究所从某制种单位随机取样获得。珍汕97A不育系和明恢63恢复系等品种由中国水稻研究所提供。在做形态观察的同时,分别取上述三种材料叶片制备DNA作为初始模板DNA。对300个RAPD随机引物,经过三次多态性初筛复筛,发现随机引物P18可以稳定地扩增出一条来源于父本明恢63的0.8kb的特异条带。用P18引物对100株汕优63杂交单株进行RAPD扩增,其中83个获得了0.8kb特异条带(Fig.1upper)。分子杂交证明其结果是可靠的(Fig.1Lower)。以RAPD扩增结果为依据,对这100株材料进行植株形态比较,发现那17个不能扩增出特异条带的单株均为假杂种。说明该制种单位汕优63的假种率为17%。大大超过农业部的有关规定。应对其原因和后果进行追究。用P18引物对18种分别为籼粳及其中间型的常用稻种进行RAPD扩增鉴定,除明恢63的亲本──圭630和中间型Pccos,Aus373具有0.8kb的特异条带? 展开更多
关键词 Hybrid rice purity of a hybrid RAPD Appraisal.
下载PDF
Purity Identification of Xinshikui 6 Using SSR Marker Technique
17
作者 柳延涛 段维 +4 位作者 刘胜利 王鹏 李万云 陈寅初 赵刚 《Agricultural Science & Technology》 CAS 2017年第2期203-206,共4页
[Objective] SSR molecular marker technique was used to determine the purity of sunflower seed with the aim to provide accurate, convenient method for the identification of the purity of hybrid seeds in production and ... [Objective] SSR molecular marker technique was used to determine the purity of sunflower seed with the aim to provide accurate, convenient method for the identification of the purity of hybrid seeds in production and processing. [Method] With the DNA of Xinshikui 6 and its parents as template, about 100 pairs of SSR molecular markers were screened after DNA extraction, PCR amplification and electrophoresis production. [Results] SSR polymorphic primer marker 532 produced a specific band of 469 bp in the female parent, and a specific band of 451 bp in the male parent; primer marker 574 produced a specific band of 364 bp in the female parent, and a specific band of 384 bp in the male parent. The indoor molecular purity identification and field purity identification were consistent with each other. The primer marker 532 and 574 could be obtained from the SSR molecular marker method to distinguish the male parent, female parent and hybrid of Xinshikui 6, and both of the 2 primer markers can effectively identify the purities of the hybrid seeds of Xinshikui 6, as well as the authenticity of the seeds. [Conclusion] The proposed method was simple, fast, accurate to operate with the advantages of high reproducibility, and it had become the major method in the identification of sunflower varieties. 展开更多
关键词 SSR marker Xinshikui 6 Variety purity identification
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
18
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)
下载PDF
Effect of indentation size and grain/sub-grain size on microhardness of high purity tungsten 被引量:2
19
作者 刘光玉 倪颂 宋旼 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第10期3240-3246,共7页
Hardness of materials depends significantly on the indentation size and grain/sub-grain size via microindentation and nanoindentation tests of high-purity tungsten with different structures.The grain boundary effect a... Hardness of materials depends significantly on the indentation size and grain/sub-grain size via microindentation and nanoindentation tests of high-purity tungsten with different structures.The grain boundary effect and indentation size effect were explored.The indentation hardness was fitted using the Nix-Gao model by considering the scaling factor.The results show that the scaling factor is barely correlated with the grain/sub-grain size.The interaction between the plastically deformed zone(PDZ) boundary and the grain/sub-grain boundary is believed to be the reason that leads to an increase of the measured hardness at the specific depths.Results also indicate that the area of the PDZ is barely correlated with the grain/sub-grain size,and the indentation hardness starts to stabilize once the PDZ expands to the dimension of an individual grain/sub-grain. 展开更多
关键词 high purity tungsten indentation hardness indentation size effect grain boundary plastic deformation zone
下载PDF
Synthesis of High Purity SiC Powder for High-resistivity SiC Single Crystals Growth 被引量:13
20
作者 Li WANG Xiaobu HU Xiangang XU Shouzheng JIANG Lina NING Minhua JIANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2007年第1期118-122,共5页
High purity silicon carbide (SIC) powder was synthesized in-situ by chemical reaction between silicon and carbon powder. In order to ensure that the impurity concentration of the resulting SiC powder is suitable for... High purity silicon carbide (SIC) powder was synthesized in-situ by chemical reaction between silicon and carbon powder. In order to ensure that the impurity concentration of the resulting SiC powder is suitable for high-resistivity SiC single crystal growth, the preparation technology of SiC powder is different from that of SiC ceramic. The influence of the shape and size of carbon particles on the morphology and phase composition of the obtained SiC powder were discussed. The phase composition and morphology of the products were investigated by X-ray diffraction, Raman microspectroscopy and scanning electron microscopy. The results show that the composition of resulting SiC by in-situ synthesis from Si/C mixture strongly depends on the nature of the carbon source, which corresponds to the particle size and shape, as well as the preparation temperature. In the experimental conditions, flake graphite is more suitable for the synthesis of SiC powder than activated carbon because of its relatively smaller particle size and flake shape, which make the conversion more complete. The major phase composition of the full conversion products is β-SiC, with traces of α-SiC. Glow discharge mass spectroscopy measurements indicated that SiC powder synthesized with this chemical reaction method can meet the purity demand for the growth of high-resistivity SiC single crystals. 展开更多
关键词 Activated carbon Flaky graphite Particle size SiC powder High purity
下载PDF
上一页 1 2 14 下一页 到第
使用帮助 返回顶部