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The Method of Testing for Asbestos in Electronic and Electric Products through Polarizing Microscope and X-Ray Diffraction 预览
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作者 Hongwei Wang Jun Liu +4 位作者 Qiang Ma Hongwei Su Deyong Liu Junfang Li Hua Bai 《电力能源(英文)》 2019年第11期35-41,共7页
Asbestos is widely applied in such sectors as manufacturing automobiles, tractors, chemical industrial equipment, and electric equipment. Asbestos fiber is harmful to human health. Therefore, the technology of testing... Asbestos is widely applied in such sectors as manufacturing automobiles, tractors, chemical industrial equipment, and electric equipment. Asbestos fiber is harmful to human health. Therefore, the technology of testing for asbestos in products is especially important. At present, in our country’s national specifications, there is no determination method or specification that is applicable to the asbestos in electronic and electric products. In this article, the components of asbestos in electronic and electric products are identified using the method of combining polarizing microscope with X-ray diffractometer. This method is simple, fast, highly reliable, and suitable to be widely adopted. 展开更多
关键词 Asbestos Polarizing MICROSCOPE X-RAY DIFFRACTION
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Synthesis, Spectroscopic Studies and X-Ray Diffraction of Heptacoordinated Mn(II) and Co(II) Complexes with Ligands Derived from Carbonohydrazide 预览
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作者 Thierno Moussa Seck Adama Sy +5 位作者 Djiby Lo Papa Aly Gaye Mohamed Lamine Sall Ousmane Diouf Mahy Diaw Mohamed Gaye 《无机化学期刊(英文)》 2019年第4期35-52,共18页
The ligand 1-(1-(pyridin-2-yl)ethylidene)carbonohydrazide (H4L1) and 1-(pyridin-2-ylmethylene)carbonohydrazide (H4L2) were prepared by reaction of carbonohydrazide with 2-acetylpyridine or pyridine carbaldehyde respec... The ligand 1-(1-(pyridin-2-yl)ethylidene)carbonohydrazide (H4L1) and 1-(pyridin-2-ylmethylene)carbonohydrazide (H4L2) were prepared by reaction of carbonohydrazide with 2-acetylpyridine or pyridine carbaldehyde respectively in a reflux methanol solution. The complexes are prepared by reaction of the ligand with the appropriate metal salt. These complexes are well characterized by elemental analysis, IR and UV spectroscopies and their structure were determined by single X-ray diffraction technic. In the crystal of the dinuclear complex [Mn2(H4L1)2(H2O)4]·Cl4, 1) each Mn(II) center is seven coordinated by two nitrogen atom and one carbonyl atom of the one ligand and one nitrogen atom and one carbonyl oxygen atom of another ligand molecule. The coordination sphere is completed by two water molecules. Each of the carbonyl oxygen atom acts as bridge between the two Mn(II) centers. In the mononuclear complex [Co(H4L2)(NO3)(H2O)2]·(NO3);2) the Co(II) center is heptacoordinated. The ligand acts in tridentate fashion through two nitrogen atoms and one carbonyl oxygen atom. Two water molecules lie in the apical positions. One nitrate group acts in bidentate manner while the other nitrate group remains uncoordinated. In both complexes the coordination polyhedral are best described as a pentagonal bipyramid. The molecules are linked together in each case by multiple hydrogen bond interaction resulting in a three-dimensional network. The crystallographic data has been deposited in Cambridge Crystallographic Data Centre [CCDC No. 1944387 (complex 1) and 1944386 (complex 2)]. 展开更多
关键词 Carbonohydrazide MANGANESE Cobalt Complex X-Ray DIFFRACTION
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Low temperature Pmmm and C2/m phases in Sr2CuO3+δ high temperature superconductor
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作者 王海波 罗震林 +5 位作者 杨远俊 刘清青 胡思侠 杨蒙蒙 靳常青 高琛 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第5期206-209,共4页
A new low temperature Pmmm (120 K) phase was found in high temperature superconductor Sr2CuO3+δ,which was indicated as a pure electronic phase by resonant x-ray diffraction at Cu K-edge.As shown by x-ray absorption f... A new low temperature Pmmm (120 K) phase was found in high temperature superconductor Sr2CuO3+δ,which was indicated as a pure electronic phase by resonant x-ray diffraction at Cu K-edge.As shown by x-ray absorption fine structure (EXAFS) and x-ray absorption near edge structure (XANES) at Cu K-edge,the strong charge density redistribution and local lattice fluctuations around Cu site at the onset of phase transition were due to the occurrence of superconductive coherence,the redistribution and fluctuation finished at Tc.Finally,the electron–lattice interaction was mainly elaborated to understand the superconductivity of Sr2CuO3+δ. 展开更多
关键词 RESONANT X-RAY diffraction X-RAY absorption fine structure MODULATED phase SUPERCONDUCTIVITY
复合绝缘子憎水特性与其微观特性的对应关系
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作者 晏年平 房子祎 +3 位作者 周东 刘玉婷 陈灿 贾志东 《高电压技术》 EI CAS CSCD 北大核心 2019年第6期1745-1753,共9页
为研究复合绝缘子憎水特性与其微观特性的对应关系,选取江西电网4串线路复合绝缘子进行憎水性及憎水性迁移试验,采用傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)以及X射线衍射(XRD)等微观分析技术,研究了绝缘子表面元素含量及化合... 为研究复合绝缘子憎水特性与其微观特性的对应关系,选取江西电网4串线路复合绝缘子进行憎水性及憎水性迁移试验,采用傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)以及X射线衍射(XRD)等微观分析技术,研究了绝缘子表面元素含量及化合态以及微观结构变化情况。研究发现,表面粉化严重的绝缘子保持较高的静态接触角,与其粉化后表面粗糙度上升密切相关;静态接触角不能作为评估粗糙表面憎水性的唯一依据,应结合绝缘子表面是否保持有足够含量的憎水性基团进行评估。复合绝缘子憎水迁移性能优劣与其表层是否存在硅氧烷XRD衍射峰具有良好的对应关系,建议测量复合绝缘子表层是否存在硅氧烷XRD衍射峰,判断其憎水迁移性能否满足继续运行要求。 展开更多
关键词 复合绝缘子 憎水特性 傅里叶红外光谱 X射线光电子能谱 X射线衍射
基于神经网络集成-X射线荧光光谱法的铁矿石中全铁含量测定 预览 被引量:1
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作者 李颖娜 徐志彬 《冶金分析》 CAS 北大核心 2019年第1期35-41,共7页
为了探索人工智能在铁矿石品质快速检验中的应用,研究了机器学习算法与化学计量学和X射线荧光光谱仪(XRF)相结合快速测定铁矿石中全铁含量的方法。收集来自于不同产地的,主要物相为赤铁矿、褐铁矿、磁铁矿、针铁矿和多物相混和结构的铁... 为了探索人工智能在铁矿石品质快速检验中的应用,研究了机器学习算法与化学计量学和X射线荧光光谱仪(XRF)相结合快速测定铁矿石中全铁含量的方法。收集来自于不同产地的,主要物相为赤铁矿、褐铁矿、磁铁矿、针铁矿和多物相混和结构的铁矿石样品共1098个作为样本集。采用X射线荧光光谱仪对铁矿石样品熔片进行扫描,扫描后的光谱图提取数据点后作为神经网络的输入,以全铁含量作为输出结果。然后依据X射线衍射(XRD)得到的物相结构优化自组织(SOM)网络,并对全部样本的XRF图谱进行分类,对分类后的每一个子集分别采用反向传播(BP)和径向基函数(RBF)网络建立回归子模型,对各子模型的预测结果进行整合,最终建立基于集成神经网络和X射线荧光光谱法的铁矿石中全铁含量预测模型。方法模型建立后,不需要额外标准物质建立校准曲线,能够实现对未知样品的分类和输出全铁含量结果。 展开更多
关键词 铁矿石 X射线荧光光谱法 X射线衍射 反向传播(BP)神经网络 径向基函数(RBF)神经网络 集成神经网络
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孕烷X受体配体结合结构域蛋白晶体的X线衍射结构解析 预览
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作者 冯帆 姜棋予 +4 位作者 孙慧伟 王祥喜 申立军 辛绍杰 李伯安 《生物技术通讯》 CAS 2019年第3期365-370,共6页
目的:利用X线衍射技术解析孕烷X受体(PXR)配体结合结构域(LBD)蛋白晶体的3维结构。方法:对PXR蛋白LBD(130~434氨基酸残基)序列进行密码子优化并化学合成后克隆至pRSFDuet-1表达载体,再将载体导入大肠杆菌BL21(DE3),对PXR-LBD蛋白进行原... 目的:利用X线衍射技术解析孕烷X受体(PXR)配体结合结构域(LBD)蛋白晶体的3维结构。方法:对PXR蛋白LBD(130~434氨基酸残基)序列进行密码子优化并化学合成后克隆至pRSFDuet-1表达载体,再将载体导入大肠杆菌BL21(DE3),对PXR-LBD蛋白进行原核表达与分离纯化;采用晶体筛选试剂盒筛选蛋白结晶条件,采用悬滴法获得目标蛋白的晶体;对获得的蛋白晶体进行X线晶体衍射检测,并收集相关数据建立PXR-LBD的三维结构。结果:获得了PXR-LBD的高质量晶体并利用X线衍射解析了该蛋白质晶体的结构数据,使用Phenix.refine软件和COOT软件等对结构进行修正,最终获得了高分辨率的3维结构数据。结论:完成了孕烷X受体配体结合结构域蛋白晶体的X线衍射结构解析,为研究和开发PXR相关药物奠定了基础。 展开更多
关键词 孕烷X受体 X线衍射 蛋白质晶体 三维维结构解析
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Inconel 718合金锻造压气机盘件的残余应力及显微组织特征 预览
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作者 徐小严 马向东 +6 位作者 王虹 叶璋 常建卫 徐瑶 孙光爱 吕维洁 高玉魁 《中国有色金属学报:英文版》 SCIE EI CAS CSCD 2019年第3期569-578,共10页
残余应力对商用发动机Inconel 718 材料构件的疲劳性能、可靠性与耐久性起着重要作用,但由于中国中子衍射测量设备与测量经验与标准的缺乏,压气机盘件的系统性残余应力研究鲜见报导。采用X 射线与中子衍射分别测量Inconel 718 锻造盘件... 残余应力对商用发动机Inconel 718 材料构件的疲劳性能、可靠性与耐久性起着重要作用,但由于中国中子衍射测量设备与测量经验与标准的缺乏,压气机盘件的系统性残余应力研究鲜见报导。采用X 射线与中子衍射分别测量Inconel 718 锻造盘件的表面及内部残余应力,采用扫描电子显微镜与透射电子显微镜观察锻造显微组织特征。锻造盘件表面呈压残余应力,内部为拉残余应力,且相比于锻造产生的残余应力,盘件表面的残余应力受粗加工影响较大。位错密度随距盘件表面的距离减小而增高,残余应力会加速位错产生与动态再结晶。 展开更多
关键词 中子衍射 X 射线衍射 残余应力 INCONEL 718 压气机盘
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NaCl单晶非切割面晶面的X射线衍射 预览
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作者 赖宣颖 王春梅 沈国土 《物理实验》 2019年第7期16-21,共6页
现有的德国莱宝X射线实验仪用默认的COUPLED模式仅能观察到NaCl单晶的(100)面衍射.同时按下TARGET,COUPLED和β-LIMIT键,可重新设置TARGET与SENSOR的测角零点,使用COUPLED模式扫描,可以观察到其他晶面的X射线衍射峰.实验观测到单晶中非... 现有的德国莱宝X射线实验仪用默认的COUPLED模式仅能观察到NaCl单晶的(100)面衍射.同时按下TARGET,COUPLED和β-LIMIT键,可重新设置TARGET与SENSOR的测角零点,使用COUPLED模式扫描,可以观察到其他晶面的X射线衍射峰.实验观测到单晶中非切割面晶面的X射线的布拉格衍射现象,且通过增大Δt,能较显著地提高衍射谱线的分辨率,但在一定的Δt仅能观察到某些晶面的1级衍射,这表明在一定的晶面序数下高的衍射级数对衍射光强的削弱作用很强. 展开更多
关键词 X射线 布拉格衍射 NaCl单晶 非切割面晶面 晶面序数 衍射级数
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新型含1,2,3-三唑基的α-氨基膦酸酯类化合物的合成及其晶体结构
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作者 王俊岭 冯书晓 +2 位作者 汪小伟 谷广娜 马军营 《分子科学学报:中英文版》 CAS 北大核心 2019年第3期253-258,共6页
在微波无溶剂无催化条件下,以2-苯基-1,2,3-三唑-4-甲醛、芳胺和亚磷酸二乙酯为原料合成了4个新型含1,2,3-三唑基的α-氨基膦酸酯类化合物.经X-射线衍射方法测定了O,O′-二乙基-α-(4-硝基苯基)氨基-α-(2-苯基-1,2,3-三唑)-4-基甲基膦... 在微波无溶剂无催化条件下,以2-苯基-1,2,3-三唑-4-甲醛、芳胺和亚磷酸二乙酯为原料合成了4个新型含1,2,3-三唑基的α-氨基膦酸酯类化合物.经X-射线衍射方法测定了O,O′-二乙基-α-(4-硝基苯基)氨基-α-(2-苯基-1,2,3-三唑)-4-基甲基膦酸酯(化合物2b)的晶体结构.晶体属三斜系,P-1空间群,晶胞参数为a=1.302 85(7)nm,b=1.305 03(8)nm,c=1.535 45(9)nm,α=76.575(5)°,β=65.737(5)°,γ=68.206(5)°,V=2.200 1(3)nm3,Dc=1.302g/cm3,μ=0.164mm-1,F(000)=904,Z=4,R1=0.061 6,wR2=0.135 5. 展开更多
关键词 三唑 氨基膦酸酯 合成 X-单晶衍射 晶体结构
高压下FeNiP的压缩性 预览
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作者 贺雪菁 KAGI Hiroyuki +1 位作者 秦善 巫翔 《高压物理学报》 CAS CSCD 北大核心 2019年第6期48-56,共9页
利用金刚石压腔技术和原位同步辐射X射线衍射技术,对FeNiP(P62m)的压缩性进行了实验研究。常温下,FeNiP在0~23.4 GPa压力范围内保持P62m结构不变。用Birch-Murnaghan状态方程对单位晶胞体积随压力的变化关系(p-V关系)进行拟合,得到:体... 利用金刚石压腔技术和原位同步辐射X射线衍射技术,对FeNiP(P62m)的压缩性进行了实验研究。常温下,FeNiP在0~23.4 GPa压力范围内保持P62m结构不变。用Birch-Murnaghan状态方程对单位晶胞体积随压力的变化关系(p-V关系)进行拟合,得到:体积模量K0=153(2)GPa,体积模量微商=5.7(2),零压下晶胞体积V0=101.6(1)Å3;或K′0=167(1)GPa,=4.0(固定值),V0=101.5(1)Å3。与Fe2P相比,FeNiP的体积模量更小,呈现出与Fe2P相反、与Ni2P相同的轴向压缩各向异性,据此探讨了Ni对(Fe,Ni)2P压缩性的影响。应用当前实验结果,估算了FeNiP、Fe2P、Fe3P、Fe2.15Ni0.85P和Fe3S在月球外核温压条件下的密度,通过与γ-Fe及月球外核密度的比较,得出Ni的加入会使“Fe-轻元素”体系的密度更接近月球外核密度,进一步阐释以多元合金体系(如Fe-Ni-S-P)为对象来研究行星核部物质组成更具合理性。 展开更多
关键词 FeNiP 金刚石压腔 X射线衍射 月球 外核
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不同地质条件及地层下煤矸石理化性质的试验研究 预览
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作者 邱继生 周云仙 +2 位作者 关虓 侯博雯 王民煌 《科学技术与工程》 北大核心 2019年第21期123-128,共6页
通过对不同地质条件和不同地层的煤矸石进行XRD(X-ray diffraction)试验及物理性能试验,分析其矿物组成与物理性能指标的内在规律。研究结果表明,煤矸石的化学成分以SiO 2和Al 2O 3为主,但不同地质条件下的煤矸石矿物组成及化学成分差... 通过对不同地质条件和不同地层的煤矸石进行XRD(X-ray diffraction)试验及物理性能试验,分析其矿物组成与物理性能指标的内在规律。研究结果表明,煤矸石的化学成分以SiO 2和Al 2O 3为主,但不同地质条件下的煤矸石矿物组成及化学成分差异较大。在物理性能方面,黄陇侏罗纪煤田煤矸石吸水率较高,表观密度较小,压碎指标较大,渭北石炭二叠纪煤田的煤矸石和陕北侏罗纪煤田的煤矸石的吸水率较小,表观密度较大和压碎指标较小。不同地层的煤矸石的矿物组成和化学成分含量相差不大,但地层越深的煤矸石吸水率越低、表观密度越大、压碎指标越小。研究成果可为不同地区煤矸石在混凝土资源化利用提供依据。 展开更多
关键词 煤矸石 X射线衍射 矿物化学成分 物理性能
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Dielectric relaxation and magneto-electric characteristics of lead-free double perovskite: Sm2NiMnO6
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作者 Rutuparna DAS R.N.P.CHOUDHARY 《先进陶瓷(英文版)》 CSCD 2019年第2期174-185,共12页
The polycrystalline sample of a double perovskite, Sm2NiMnO6 was synthesized by a solid-state reaction route. From the X-ray structural study, it is found that the structure of the material is monoclinic with lattice ... The polycrystalline sample of a double perovskite, Sm2NiMnO6 was synthesized by a solid-state reaction route. From the X-ray structural study, it is found that the structure of the material is monoclinic with lattice parameters: a = 4.1750(63) ?, b = 7.6113(63) ?, c = 5.9896(63) ?, and β = 112.70°. These parameters are very close to and consistent with those of such type of materials. The dielectric, impedance, AC conductivity, and electrical modulus properties of the sample were studied in the temperature range of 25–300℃ and the frequency range of 1 kHz–1 MHz. Typical relaxor behavior observed in the dielectric studies was confirmed by Vogel–Fulcher fitting. From the Nyquist plots, the temperature dependent contribution of grain and grain boundary effect was confirmed. The non-Debye type of relaxation was found using the complex impedance spectroscopy. The magnetic study revealed that the sample had paramagnetic behavior at room temperature. Magneto-electric(ME) coefficient was obtained by changing DC bias magnetic field. This type of lead-free relaxor ferroelectric compound may be useful for high-temperature applications. 展开更多
关键词 SOLID-STATE reaction X-ray diffraction(XRD) dielectric RELAXATION magneto-electric(ME) coupling
Spatial distribution and formation mechanism of aeolian sand in the middle reaches of the Yarlung Zangbo River
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作者 LIU Yong WANG Yun-sheng SHEN Tong 《山地科学学报:英文版》 SCIE CSCD 2019年第9期1987-2000,共14页
Aeolian sand landforms in the Yarlung Zangbo River(YZR) valley are a special type of aeolian landform that has attracted the attention of many scholars. However, the spatial distribution as well as the formation mecha... Aeolian sand landforms in the Yarlung Zangbo River(YZR) valley are a special type of aeolian landform that has attracted the attention of many scholars. However, the spatial distribution as well as the formation mechanism of aeolian sand has rarely been reported with integrated studies. In this paper, for remote sensing interpretation, scanning electron microscopy(SEM), X-ray diffraction(XRD) and particle size distribution(PSD) methods were used to analyze the spatial distribution and the deposition characteristics of aeolian sand. Combined with wind data and topography, the main driving factors and the formation mechanism of aeolian sand landforms were also examined. In the middle reaches of the YZR valley, there is a total of 2324.43 km~2 of aeolian sand, especially on the north bank of the wide valleys. In different wide valleys, the aeolian sand landforms exhibit a decreasing trend from the upstream to the downstream regions in both the area and expansion rate of aeolian sand. The cyclonic vortexes generated by the westerly winds and glacial winds are the main driving factors for transporting alluvial sand to the riverbank areas to form aeolian dunes. There are three main types of sand dunes in the river valley: climbing dunes, lee dunes and circumfluent dunes. Climbing dunes and lee dunes are mostly located west of the Jiacha Gorge, and the circumfluent dunes are mostly located east of the Jiacha Gorge. 展开更多
关键词 Aeolian processes Remote sensing interpretation Scanning electron microscopy X-ray DIFFRACTION Particle size distribution GLACIAL winds Cyclonic vortexes
淹水对土壤重金属浸出行为的影响及机制
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作者 杨宾 罗会龙 +3 位作者 刘士清 韩聪 宋秋浩 曹云者 《环境工程学报》 CAS CSCD 北大核心 2019年第4期936-943,共8页
为了明确淹水对土壤重金属浸出行为的影响及其作用机制,以实际场地重金属污染土壤为研究对象,开展了淹水实验。对淹水过程中土壤重金属的浸出浓度、氧化还原电位、pH、铁氧化物浓度及重金属形态等相关指标进行测定了分析。结果表明,淹水... 为了明确淹水对土壤重金属浸出行为的影响及其作用机制,以实际场地重金属污染土壤为研究对象,开展了淹水实验。对淹水过程中土壤重金属的浸出浓度、氧化还原电位、pH、铁氧化物浓度及重金属形态等相关指标进行测定了分析。结果表明,淹水后,重金属浸出浓度随淹水时间呈现先增长后降低趋势。淹水初期(30 d),Cu、Zn、Cd和Pb浸出浓度分别增加了6.71%、4.03%、3.56%和4.55%。pH降低、有机质降解和铁氧化物还原溶解是导致重金属浸出浓度升高的主要原因。随淹水时间的持续增加,重金属浸出浓度逐渐降低并于90 d时趋于稳定。淹水结束时(180 d),Cu、Zn、Cd和Pb浸出浓度分别降低了23.78%、16.78%、15.48%和15.45%。重金属形态分析表明,淹水促使重金属赋存形态由酸可提取态转化为可还原态和可氧化态,降低了重金属活性;矿物成份分析证实了金属硫化铜物相的生成。新形成的无定形氧化铁对重金属的吸附作用和硫化物与重金属的化学沉淀作用是重金属浸出浓度降低的主要机制。该研究为淹水条件下重金属污染土壤风险控制提供了依据。 展开更多
关键词 土壤污染 重金属 淹水实验 浸出浓度 重金属形态 X射线衍射分析
Hydrogen Bonding Assembled 3D Supramolecular Structures Formed by 5-Amino-2,4,6-triiodoisophthalic Acid and TV-Heterocyclic Aromatic Ligands
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作者 YU Wenli ZHANG Mingjuan +2 位作者 LIU Kang YANG Yu WANG Lei 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第5期806-811,共6页
Three salts constructed by 5-amino-2,4,6-triiodoisophthalic acid(ATIPA) with N-heterocycles aromatic coformers such as pyridine tetrazolium, tetramethylpyraziiie and cyanuric acid were synthesized by slowing evaporati... Three salts constructed by 5-amino-2,4,6-triiodoisophthalic acid(ATIPA) with N-heterocycles aromatic coformers such as pyridine tetrazolium, tetramethylpyraziiie and cyanuric acid were synthesized by slowing evaporation of solvent. X-Ray single crystal analysis shows that hydrogen protons of the carboxyl groups transfer to nitrogen atoms of the N-heterocyclic coformers to form N-H…0 hydrogen bonds in all the three compounds. A huge amount of H-bonds play significant role in tlie construction of these compounds and all of them generate 3D structures through strong O-H…N, O-H…O, N-H…O and weak C-H…O hydrogen bonds. Moreover, solvent water molecules are indispensable in the formation of compounds 1 and 3, which constitutes different supramolecular synthons to bridge individual molecules and chains to form stable structures. In addition, these crystal structures were further characterized by themiogravimetric analysis and infrared spectroscopy. 展开更多
关键词 Hydrogen bond SUPRAMOLECULAR structure X-Ray diffraction N-Heterocyclic AROMATIC ligand
中药珍珠层粉X射线衍射指纹图谱研究
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作者 乔艺涵 索亚然 +7 位作者 孟雪丹 姬蕾 张文婷 陈龙 滕传震 赵崇军 林瑞超 邹迪新 《药物分析杂志》 CAS CSCD 北大核心 2019年第5期911-918,共8页
目的:建立中药珍珠层粉X射线衍射指纹图谱,为珍珠层粉质量评价提供新的方法。方法:采用X射线衍射技术对珍珠层粉进行定性分析,并对21批不同基原和产地的珍珠层粉进行评价。结果:得到了21批珍珠层粉的X射线衍射图谱,其中18批样品的衍射... 目的:建立中药珍珠层粉X射线衍射指纹图谱,为珍珠层粉质量评价提供新的方法。方法:采用X射线衍射技术对珍珠层粉进行定性分析,并对21批不同基原和产地的珍珠层粉进行评价。结果:得到了21批珍珠层粉的X射线衍射图谱,其中18批样品的衍射图谱几何拓扑特征基本一致,利用这18批珍珠层粉的X射线衍射图谱,建立中药珍珠层粉的X射线衍射指纹图谱,并建立其对照图谱,经过寻峰处理得到共有峰,以夹角余弦法和相关系数法计算18批珍珠层粉X射线衍射图谱的相似度,发现不同样品X射线衍射图谱具有较高的相似度,而劣质珍珠层粉的X射线衍射图谱与正品存在显著差别。结论:X射线衍射指纹图谱分析方法专属性强,准确可靠,可实现对中药珍珠层粉的鉴别和质量评价。 展开更多
关键词 珍珠层粉 X射线衍射 指纹图谱 相似度 质量评价
Mineral phase and structure changes during roasting of fine-grained carbonaceous gold ores and their effects on gold leaching efficiency
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作者 Jianping Jin Yuexin Han +4 位作者 Hui Li Yangyang Huai Yongjun Peng Xiaotian Gu Wei Yang 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第5期1184-1190,共7页
While roasting has been widely applied to reduce the negative effect of carbonaceous matters on gold extraction from fine-grained carbonaceous gold ores, the phase and structure changes of minerals during roasting and... While roasting has been widely applied to reduce the negative effect of carbonaceous matters on gold extraction from fine-grained carbonaceous gold ores, the phase and structure changes of minerals during roasting and their in fluences on the leachi ng rate of gold have not been fully understood. This limits the extraction of carbonaceous gold deposits. The current work examines the oxidation process of a fine-grained carbonaceous gold ore during roasting using a range of techniques including X-ray diffraction (XRD), seanning electron microscopy (SEM), Energy Dispersive Spectrometer (EDS) analysis and pore structure analysis together with gold leaching tests. The results show that during the process of oxidative roasting, the carbonaceous matters (organic carbon and graphitic carbon) and pyrite were completely decomposed at 600 ℃ with the carbonaceous components burned and pyrite oxidized into hematite. At 650 ℃, while dolomite was decomposed into calcia, magnesia, calcium sulfate etc., the calcine structure became loose and porous, leading to a high gold leaching rate from the roasted product. Above 750 ℃, the porous calcite structure started to collapse along with the agglomeration, leading to the secondary encapsulation of gold particles, which contributed to the sharp drop in the gold leaching rate of the roasted product. This study suggests optimum phase and structure changes of minerals during roasting to achieve maximum gold extraction from fine-grained carbonaceous gold deposits. 展开更多
关键词 CARBONACEOUS gold ore ROASTING LEACHING X-ray DIFFRACTION (XRD) Scanning electron MICROSCOPY (SEM)
Synthesis, Structure and Biological Activity of 2-[2-(4-Fluorobenzylidene)hydrazinyl]-4-(1-methyl-1H-indol-3-yl)thieno[3,2-d]pyrimidine 预览
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作者 史建涛 宫益林 +4 位作者 李军 王洋 陈烨 丁实 刘举 《结构化学》 SCIE CAS CSCD 2019年第9期1530-1536,共7页
The title compound 2-[2-(4-fluorobenzylidene)hydrazinyl]-4-(1-methyl-1 H-indol-3-yl)thieno[3,2-d] pyrimidine(8) was synthesized by the condensation of 4-fluorobenzaldehyde(7) with 2-hydrazinyl-4-(1-methyl-1 H-indol-3-... The title compound 2-[2-(4-fluorobenzylidene)hydrazinyl]-4-(1-methyl-1 H-indol-3-yl)thieno[3,2-d] pyrimidine(8) was synthesized by the condensation of 4-fluorobenzaldehyde(7) with 2-hydrazinyl-4-(1-methyl-1 H-indol-3-yl)thieno[3,2-d]pyrimidine(6). This intermediate was prepared from methyl 3-aminothiophene-2-carboxylate(1) by the condensation with urea, chlorination with phosphorus oxychloride and then condensation with hydrazine hydrate. The crystal of 8 belongs to monoclinic system, space group P21/c with a = 14.0453(18), b = 17.436(2), c = 18.0982(17) ? and β = 122.969(7)°. In addition, 8 possesses marked inhibition against the proliferation of human colon cancer cell line HT-29(IC50 = 6.09 μM) and human gastric cancer cell line MKN45(IC50 = 3.04 μM), displaying promising anticancer activity. 展开更多
关键词 thieno[3 2-d] PYRIMIDINE SYNTHESIS X-ray DIFFRACTION ANTITUMOR activity
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Influence of Replacement Level of Coal-series Kaolin on Hydration of Ordinary Portland Cement by X-ray Diffraction/Rietveld Method
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作者 刘园圆 雷绍民 +2 位作者 LI Yang XIE Feixiang LI Bo 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第3期614-621,共8页
The influence of replacement level of calcined coal-series kaolin (CCK) on hydration of ordinary Portland cement (OPC) was studied by X-ray diffraction(XRD)/Rietveld method. X-ray diffraction/ Rietveld method was used... The influence of replacement level of calcined coal-series kaolin (CCK) on hydration of ordinary Portland cement (OPC) was studied by X-ray diffraction(XRD)/Rietveld method. X-ray diffraction/ Rietveld method was used to quantify the crystalline phase composition of the hydrated samples. Additionally, the morphology of hydrated samples was observed by scanning electron microscopy (SEM). The results showed that, calcium hydroxide (CH), ettringite (AFt) and amorphous phase content in hydrated samples decreased as the replacement level of CCK increased, while AFm and stratiingite increased, which was caused by the combination of dilute, physical and pozzolanic effects. The hydration of anhydrous cement phases was accelerated by physical effect but hindered by the retardation effect of CCK. The role of each effects was discussed in detail to analyze the mechanism of OPC hydration with CCK addition. The SEM images showed that the shortening of AFt at 1 day and the denser texture at 28 days was observed with CCK addition, which was caused by the physical and pozzolanic effects, respectively. 展开更多
关键词 CALCINED coal-series KAOLIN X-ray diffraction/rietveld method HYDRATION cement PASTE morphology
Synthesis and Cytotoxicity of the First Arene Ruthenium Compound Containing Two Thiosemicarbazone Ligands 预览
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作者 苏炜 罗志进 +3 位作者 崔浩 唐兆丰 李培源 彭炳华 《结构化学》 SCIE CAS CSCD 2019年第9期1543-1548,共6页
A Ru-arene compound containing two thiosemicarbazone ligands [(η6-p-cymene)Ru(TSC)2 Cl]Cl(1, TSC = benzophenone 4-methylthiosemicarbazone) has been synthesized and characterized by 1 H NMR, elemental analysis and HR-... A Ru-arene compound containing two thiosemicarbazone ligands [(η6-p-cymene)Ru(TSC)2 Cl]Cl(1, TSC = benzophenone 4-methylthiosemicarbazone) has been synthesized and characterized by 1 H NMR, elemental analysis and HR-ESI mass spectrometry analysis. The molecular structure was determined by single-crystal X-ray diffraction analysis. The in vitro anticancer activities of the complex have been evaluated against two human cancer cell lines(SGC-7901, BEL-7404), and the IC50 values are 32.5 and 57 μM, respectively. 展开更多
关键词 RUTHENIUM ARENE THIOSEMICARBAZONES X-ray crystal diffraction CYTOTOXICITY running head ARENE RUTHENIUM compound containing TSC
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