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Thin Layer Identification of Jiedu Shengxue Granules and Determination of Notoginsenoside R1 Content
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作者 Zhenying FU Bing QING +6 位作者 Yinghong HUANG Xianyi SHI Meiyan QIU Xian PENG Jiangcun WEI Fengzhen LI Wen ZHONG 《Medicinal Plant》 2024年第1期71-74,共4页
[Objectives]To establish the quality standard of hospital preparation Jiedu Shengxue granules.[Methods]Scleromitrion diffusum and Prunella vulgaris in Jiedu Shengxue granules were qualitatively identified by thin laye... [Objectives]To establish the quality standard of hospital preparation Jiedu Shengxue granules.[Methods]Scleromitrion diffusum and Prunella vulgaris in Jiedu Shengxue granules were qualitatively identified by thin layer chromatography(TLC).A high performance liquid chromatography(HPLC)was established to determine the content of notoginsenoside R1 in the granule.[Results]The traditional Chinese medicinal materials in Jiedu Shengxue granules could be identified by TLC,and the characteristic spots were stable and clear.Notoginsenoside R1 had a good linear relationship in the range of 10.45-104.5μg/mL,with an average recovery of 98.52%and RSD=2.36%.[Conclusions]TLC and HPLC,as the quality control methods of Jiedu Shengxue granules,have high accuracy and good repeatability,which lays a foundation for the quality control of this mixture. 展开更多
关键词 Jiedu Shengxue granules Thin layer identification Notoginsenoside R1 Quality standard
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MPEG-1 Layer2双声道定点音频编码器的硬件设计
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作者 史伟伟 赵光东 +2 位作者 徐渊 易子林 周德福 《计算机与数字工程》 2017年第7期1444-1447,1463,共5页
MEPG-1 Layer2音频编解码在数字视音频广播领域有着广泛的应用。现有的MEPG-1 Layer2音频编码方案大多在DSP/CPU平台上用软件方式实现,算法本身实现起来复杂,且浮点数的运算本身占用更多的CPU资源,要实现实时性更多的依赖CPU的性能。论... MEPG-1 Layer2音频编解码在数字视音频广播领域有着广泛的应用。现有的MEPG-1 Layer2音频编码方案大多在DSP/CPU平台上用软件方式实现,算法本身实现起来复杂,且浮点数的运算本身占用更多的CPU资源,要实现实时性更多的依赖CPU的性能。论文采用全硬件的设计方法,设计实现了MEPG-1 Layer2双声道音频编码器,简化了算法的复杂度且实现了定点数的运算,使用Xilinx提供的ISE完成verilog代码的编写与综合,第三方软件Modelsim完成各功能模块的仿真,在VC707上完成验证,和MEPG-1 Layer2的音频软件编码相比实时性更好,资源使用更少。 展开更多
关键词 MEPG-1layer2 MODELSIM 实时 VERILOG
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Uniform AlF_3 thin layer to improve rate capability of LiNi_(1/3)Co_(1/3) Mn_(1/3)O_2 material for Li-ion batteries 被引量:3
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作者 王海燕 唐爱东 +1 位作者 黄可龙 刘素琴 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期803-808,共6页
LiNi1/3Co1/3Mn1/3O2 was coated with uniform nano-sized AlF3 layer by chemical precipitation method to improve its rate capability.The samples were characterized by X-ray diffractometry (XRD),transmission electron micr... LiNi1/3Co1/3Mn1/3O2 was coated with uniform nano-sized AlF3 layer by chemical precipitation method to improve its rate capability.The samples were characterized by X-ray diffractometry (XRD),transmission electron microscopy (TEM),energy dispersive spectroscopy (EDS),charge-discharge cycling,cyclic voltammetry (CV),and electrochemical impedance spectroscopy (EIS).Uniform coated layer with a thickness of about 3 nm was observed on the surface of LiNi1/3Co1/3Mn1/3O2 particle by TEM.At 0.5C and 2C rates,1.5% (mass fraction) AlF3-coated LiNi1/3Co1/3Mn1/3O2/Li in 2.8-4.3 V versus Li/Li+ after 80 cycles showed less than 3% of capacity fading,while those of the bare one were 16.5% and 45.9%,respectively.At 5C rate,the capacity retention of the coated sample after 50 cycles maintained 91.4% of the initial discharge capacity,while that of the bare one decreased to 52.6%.EIS result showed that a little change of charge transfer resistance of the coated sample resulting from uniform thin AlF3 layer was proposed as the main reason why its rate capability was improved obviously.CV result further indicated a greater reversibility for the electrode processes and better electrochemical performance of AlF3-coated layer. 展开更多
关键词 Li-ion battery LINI1/3CO1/3MN1/3O2 coating uniform thin AlF3 layer rate capability
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Effects of ZnO Buffer Layer Thickness on Properties of Mg_xZn_(1-x)O Thin Films Deposited by MOCVD 被引量:1
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作者 DONG Xin LIU Da-li +4 位作者 DU Guo-tong ZHANG Yuan-tao ZHU Hui-chao YAN Xiao-long GAO Zhong-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第5期583-586,共4页
High-quality MgxZn1-xO thin films were grown on sapphire(0001 ) substrates with a ZnO buffer layer of different thicknesses by means of metal-organic chemical vapor deposition. Diethyl zinc, bis-cyclopentadienyl-Mg ... High-quality MgxZn1-xO thin films were grown on sapphire(0001 ) substrates with a ZnO buffer layer of different thicknesses by means of metal-organic chemical vapor deposition. Diethyl zinc, bis-cyclopentadienyl-Mg and oxygen were used as the precursor materials. The crystalline quality, surface morphologies and optical properties of the Mg, Zn1-xO films were investigated by X-ray diffraction, atomic force microscopy and photoluminescence spectrometry. It was shown that the quality of the MgxZn1-xO thin films depends on the thickness of the ZnO buffer layer and an Mg, Zn1-xO thin film with a ZnO buffer layer whose thickness was 20 nm exhibited the best crystal-quality, optical properties and a flat and dense surface. 展开更多
关键词 MGXZN1-XO ZnO Buffer layer Sapphire substrate MOCVD AFM
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Hydrothermal Synthesis and Crystal Structure of a New 2D Layered Cadmium(II) Coordination Polymer:[Cd(bimc)_2]_n(bimc=1H-Benzimidazole-5-carboxylate) 被引量:1
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作者 DENG Qian-Jun ZENG Ming-Hua +1 位作者 LIANG Hong HUANG Ke-Long 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期975-978,共4页
A new coordination polymer [Cd(bimc)2]n was obtained by the reaction of Hbimc with Cd(NO3) 2·4H2O in NaOH solution, and characterized by elemental analysis, IR and singlecrystal X-ray diffraction. The crystal... A new coordination polymer [Cd(bimc)2]n was obtained by the reaction of Hbimc with Cd(NO3) 2·4H2O in NaOH solution, and characterized by elemental analysis, IR and singlecrystal X-ray diffraction. The crystal belongs to orthorhombic, space group Pbcn with a = 12.533(4), b = 15.705(5), c = 15.200(5) A, V= 2991.8(15) A^3, Mr = 434.68, Z = 8, Dc = 1.930 g/cm^3, F(000) = 1712,μ(MoKa) = 1.492 mm^-1, the final R = 0.0410 and wR = 0.0804 for 1661 observed reflections (I 〉 2σ(I)). The Cd atom exhibits a distorted six-coordinate CdNzOa octahedral coordination geometry. The complex molecules are linked by both μ2-(η2-O, O^-), NI and μ2-(η2-O, O^-), N3 coordination modes of ligands to form cross-like wave (4, 4) layer structures which are further stacked through interlayer hydrogen bonds and π-π stacking interactions in an offset fashion to form a 3D supramolecular structure. 展开更多
关键词 hydrothermal synthesis cadmium(Ⅱ) polymer 1H-benzimidazole-5-carbonate 2D layer
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Weak Interactions and 2D Layer Structure of a New Ion-pair Complex Bis(1-benzyl-4-methylquinolinium)-bis(maleonitriledithiolato)nickel(Ⅱ)
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作者 周家容 倪春林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第11期1263-1266,共4页
A new ion-pair complex, [BzMeQ1]2[Ni(nmt)2]1([BzMeQ1]^+ = 1-benzyl-4-ntethylquino- linium, mnta- -- maleonitriledithiolate) has been synthesized and structurally characterized by IR, ESI-MS and X-ray diffraction ... A new ion-pair complex, [BzMeQ1]2[Ni(nmt)2]1([BzMeQ1]^+ = 1-benzyl-4-ntethylquino- linium, mnta- -- maleonitriledithiolate) has been synthesized and structurally characterized by IR, ESI-MS and X-ray diffraction methods. Complex 1 is of triclinic, space group PI, with a = 9.079(2), b = 10.154(2), c = 11.243(2)A, α= 81.58(1), β= 69.63(1), γ = 68.02(1)°, V= 940.1(3)A3, Dc = 1.427 g/cm^3, Z = 1, F(000) = 418 and R = 0.0442. A 2D layer structure is formed via the cation-cation π…π and C-H…π interactions observed in the solid state of the complex. 展开更多
关键词 1-benzyl-4-methylquinolinium bis (maleonitriledithiolate)nickclatc(Ⅱ) complex weak interactions 2D layer structure
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Proposal and Achievement of a Relatively Al-rich Interlayer for In-rich Al_x In_(1-x)N Films Deposition
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作者 吕默 DONG Chengjun 王一丁 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第5期868-875,共8页
Ternary In-rich AlxIn1-x N films were successfully grown on Si (111) and (0001) sapphire substrates by radio-frequency magnetron sputtering on a relatively Al-rich AlxIn1-x N layer after AlN buffer. X-ray diffract... Ternary In-rich AlxIn1-x N films were successfully grown on Si (111) and (0001) sapphire substrates by radio-frequency magnetron sputtering on a relatively Al-rich AlxIn1-x N layer after AlN buffer. X-ray diffraction (XRD) patterns of the films indicate highly c axis-oriented wurtzite structure and the indium content of about 0.76 has been evaluated according to the Vegard's law. An Al-rich AlxIn1-xN transition layer was formed between the ultimate In-rich AlxIn1-x N film and the AlN buffer, which served as a further buffer to alleviate mismatch. X-ray photoelectron spectroscopy (XPS) depth profiling analyses confirm the alternative of indium and aluminum composition and the unavoidable oxygen impurities from surface to bulk. Owing to high indium content, obvious E2u and InN-like Al (LO) phonon model accompanying with slight A1N-like A1 (LO) phonon model are observed. Hall effect measurements demonstrate n-type electrical conductivity in these alloys with carrier concentrations n=1019 cm-3. The strain in In-rich AlxIn1-x N films can be significantly reduced by introducing an Al-rich interlayer, facilitating the improvement of film quality for diverse device applications. 展开更多
关键词 AlxIn1-x N film magnetron sputtering buffer layer microstructure
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Environmentally Friendly Room Temperature Synthesis of 1-Tetralone over Layered Double Hydroxide-Hosted Sulphonato-Salen-Nickel(II) Complex
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作者 Samiran Bhattacharjee Mohammad A. Matin +1 位作者 Hasina Akhter Simol Anowar Hosen 《Green and Sustainable Chemistry》 CAS 2023年第1期9-22,共14页
1-Tetralone, a useful synthetic intermediate in the manufacture of pharmaceuticals, agrochemicals and dyes, can be prepared by liquid phase catalytic oxidation of tetralin. Selective oxidation of tetralin to 1-tetralo... 1-Tetralone, a useful synthetic intermediate in the manufacture of pharmaceuticals, agrochemicals and dyes, can be prepared by liquid phase catalytic oxidation of tetralin. Selective oxidation of tetralin to 1-tetralone is still a big challenge with low-temperature processes using environmentally friendly routes even after decades of research. Herein, we demonstrate room-temperature oxidation of tetralin to 1-tetralone over layered double hydroxide-hosted sulphonato-salen-nickel(II) complex, LDH-[Ni-salen]. The layered double hydroxide-hosted sulphonato-salen-nickel(II) compound was characterized by powder X-ray diffraction, Fourier transform infrared spectrometer (FTIR), UV-Visible diffuse reflectance spectra, scanning electron microscopy (SEM) and elemental analysis. The theoretical calculations of free sulphonato-salen-nickel(II) complex using Density Functional Theory/CAM-B3LYP at the 6-311++ G(d,p) level of theory were also used to determine the orientation of the Ni-salen compound within the layered structure. The immobilized compound, LDH-[Ni-salen] was found to be an effective reusable catalyst for the oxidation of tetralin to 1-tetralone using a combination of trimethylacetaldehyde and molecular oxygen (14.5 psi) and at 25&deg;C. At 45.5% conversion, tetralin was converted to 1-tetralone with 77.2% selectivity at room temperature and atmospheric pressure after 24 h. The catalyst recycles test and hot filtration experiment showed that oxidation proceeded through Ni(II) sites in LDH-[Ni-salen]. The catalysts were reused several times without losing their catalytic activity and selectivity. The present results may provide a convenient strategy for the preparation of 1-tetralone using layered double hydroxide-based heterogeneous catalyst at ambient temperature for industrial application in near future. 展开更多
关键词 Sulphonato-Salen-Nickel(II) layered Double Hydroxide Tetralin Oxidation Room Temperature 1-Tetralone
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不同层电荷数钙蒙脱石对黄曲霉毒素B_(1)的吸附性能与机理研究
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作者 肖莎 彭同江 +1 位作者 孙红娟 张伟 《硅酸盐通报》 CAS 北大核心 2024年第1期172-182,共11页
以内蒙古、新疆及辽宁三地的钙基膨润土为研究对象,探究不同层电荷数钙蒙脱石对黄曲霉毒素B1(AFB_(1))的吸附性能与机理。采用X射线衍射仪、红外光谱仪、高效液相色谱仪等测试手段,研究不同产地膨润土的矿物学属性、理化性能及钙蒙脱石... 以内蒙古、新疆及辽宁三地的钙基膨润土为研究对象,探究不同层电荷数钙蒙脱石对黄曲霉毒素B1(AFB_(1))的吸附性能与机理。采用X射线衍射仪、红外光谱仪、高效液相色谱仪等测试手段,研究不同产地膨润土的矿物学属性、理化性能及钙蒙脱石吸附AFB_(1)的动力学和等温吸附作用。结果表明,钙蒙脱石含量高、比表面积大、层电荷数高的内蒙古膨润土(N-Mt)吸附性能较好,当初始浓度为1.5 mg/L、吸附剂用量为5 mg时,N-Mt对AFB_(1)的饱和吸附量为1.153 mg/g,吸附过程受pH值影响较小。钙蒙脱石对AFB_(1)的吸附行为同时符合准一级动力学模型和准二级动力学模型,表明吸附过程可能同时涉及物理吸附和化学吸附。钙蒙脱石与AFB_(1)之间的吸附作用同时发生在层间域和层面上,该作用主要源于电子供体-受体结合作用和钙蒙脱石与AFB_(1)分子之间的离子-偶极相互作用。钙蒙脱石对AFB_(1)的等温吸附符合Langmuir模型,属单分子层吸附。 展开更多
关键词 膨润土 蒙脱石 层电荷 黄曲霉毒素B_(1) 吸附性能 吸附机理
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Effect of the Compound Layer of Plasma Nitriding on Thermal Fatigue Behavior of 4Cr5MoSiV1 Die Steel
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作者 彭文屹 吴晓春 +1 位作者 闵永安 许珞萍 《Journal of Shanghai University(English Edition)》 CAS 2003年第1期87-92,共6页
With the Uddeholm self restricted method, the effect of compound layer of plasma nitriding on thermal fatigue behavior of 4Cr5MoSiV1 steel was studied by the way of adding Ar during plasma nitriding to remove the com... With the Uddeholm self restricted method, the effect of compound layer of plasma nitriding on thermal fatigue behavior of 4Cr5MoSiV1 steel was studied by the way of adding Ar during plasma nitriding to remove the compound layer. The results show that the compound layer of plasma nitriding can delay the nucleation of heat cracks and hold back the propagation of heat cracks from surface to substrate because of its high hardness and strength. On the other land, the heat checking expands faster with the compound layer on the surface than that without it. After 3000 cycles of thermal fatigue test, both heat cracks with the compound layer are wider than the another without compound layer and the number of heat cracks of the former is more from the view of cross section. 展开更多
关键词 Cr5MoSiV1 steel plasma nitriding compound layer thermal fatigue behavior thermal stress.
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Characterization of Cd1-xZnxTe(0≤x≤1) Nanolayers Grown by Atomic Layer Deposition on GaSb and GaAs(001) Oriented Substrates
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作者 Joel Díaz-Reyes Roberto Saúl Castillo-Ojeda José Eladio Flores-Mena 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第2期97-108,共12页
ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these material... ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these materials have acquired renewed importance due to the new explored nanolayer properties of modern devices. In addition, as shown in this work they can be grown using uncomplicated synthesis techniques based on the deposition in vapour phase of the elemental precursors. This work presents the results obtained from the deposition of nanolayers of these materials using the precursor vapour on GaAs and GaSb (001) substrates. This growth technique, extensively known as atomic layer deposition (ALD), allows the layers growth with nanometric dimension. The main results presented in this work are the used growth parameters and the results of the structural characterization of the layers by the means of Raman spectroscopy measurements. Raman scattering shows the peak corresponding to longitudinal optical (LO)-ZnTe, which is weak and slightly redshift in comparison with that reported for the ZnTe bulk at 210 cm^-1. For the case of the CdTe nanolayer, Raman spectra presented the LO-CdTe peak, which is indicative of the successful growth of the layer. Its weak and slightly redshift in comparison with that reported for the CdTe bulk can be related with the nanometric characteristic of this layer. The performed high-resolution X-ray diffraction (HR-XRD) measurement allows to study some important characteristics such as the crystallinity of the grown layer. In addition, the HR-XRD measurement suggests that the crystalline quality has dependence on the growth temperature. 展开更多
关键词 Ⅲ-Ⅴ SUBSTRATES atomic layer deposition(ALD) defect generation mechanism TERNARY alloy Cd1-xZnxTe Zn and Cd mixture
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Simulation Study of CuO-Based Solar Cell with Different Buffer Layers Using SCAPS-1D
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作者 Towhid Adnan Chowdhury 《Energy and Power Engineering》 2023年第9期307-314,共8页
In copper oxide (CuO) based solar cells, various buffer layers such as CdS, In<sub>2</sub>S<sub>3</sub>, WS<sub>2</sub> and IGZO have been investigated by solar cell capacitance sim... In copper oxide (CuO) based solar cells, various buffer layers such as CdS, In<sub>2</sub>S<sub>3</sub>, WS<sub>2</sub> and IGZO have been investigated by solar cell capacitance simulator (SCAPS) in this work. By varying absorber and buffer layer thickness, photovoltaic parameters (open circuit voltage, fill factor, short-circuit current density and efficiency) are determined. The highest efficiency achieved is 19.6% with WS<sub>2</sub> buffer layer. The impact of temperature on all CuO-based solar cells is also investigated. 展开更多
关键词 Solar cell Buffer layer EFFICIENCY Hetero-Junction Scaps-1D
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SphK/S1P在心血管疾病中的作用
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作者 唐丽鸿 陈春玲 《基础医学与临床》 CAS 2024年第8期1175-1179,共5页
磷酸鞘氨醇(S1P)是一种活性高的膜磷脂类代谢物,对心血管系统具有重要的生理作用。鞘氨醇激酶(SphK)是一种脂肪酶,对维持体内S1P水平的稳定非常重要。S1P通过催化调节与细胞表面的G蛋白偶联受体(S1PR1-5)的结合,从而在心血管疾病中发挥... 磷酸鞘氨醇(S1P)是一种活性高的膜磷脂类代谢物,对心血管系统具有重要的生理作用。鞘氨醇激酶(SphK)是一种脂肪酶,对维持体内S1P水平的稳定非常重要。S1P通过催化调节与细胞表面的G蛋白偶联受体(S1PR1-5)的结合,从而在心血管疾病中发挥不同的生理学效应,如参与调控动脉粥样硬化、心肌缺血再灌注损伤、心肌梗死、心力衰竭等疾病的发生发展,维持血管内皮细胞屏障功能,保护内皮糖萼层,白细胞黏附以及炎性反应等生理病理过程。 展开更多
关键词 1-磷酸鞘氨醇 鞘胺醇激酶 心血管疾病 内皮糖萼层
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Similarities and differences in inherent mechanism and characteristic frequency between the one-dimensional poroelastic model and the layered White model
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作者 Li-Ming Zhao Cai-Ping Lu +1 位作者 Yang Liu Chao-Chao Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2383-2392,共10页
The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D)poroelastic model and the layered White model were investigated.This investigation was conducted under ... The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D)poroelastic model and the layered White model were investigated.This investigation was conducted under the assumption that the rock was homogenous and isotropic at the mesoscopic scale.For the inherent mechanism,both models resulted from quasi-static flow in a slow P-wave diffusion mode,and the differences between them originated from saturated fluids and boundary conditions.On the other hand,for the characteristic frequencies of the models,the characteristic frequency of the 1D poroelastic model was first modified because the elastic constant and formula for calculating it were misused and then compared to that of the layered White model.Both of them moved towards higher frequencies with increasing permeability and decreasing viscosity and diffusion length.The differences between them were due to the diffusion length.The diffusion length for the 1D poroelastic model was determined by the sample length,whereas that for the layered White model was determined by the length of the representative elementary volume(REV).Subsequently,a numerical example was presented to demonstrate the similarities and differences between the models.Finally,published experimental data were interpreted using the 1D poroelastic model combined with the Cole-Cole model.The prediction of the combined model was in good agreement with the experimental data,thereby validating the effectiveness of the 1D poroelastic model.Furthermore,the modified characteristic frequency in our study was much closer to the experimental data than the previous prediction,validating the effectiveness of our modification of the characteristic frequency of the 1D poroelastic model.The investigation provided insight into the internal relationship between wave-induced fluid flow(WIFF)models at macroscopic and mesoscopic scales and can aid in a better understanding of the elastic modulus dispersion and attenuation caused by the WIFF at different scales. 展开更多
关键词 1D poroelastic model layered White model Quasi-static flow Slow P-wave diffusion Characteristic frequency Diffusion length
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Composition and Assemblage Characteristics of Magnetic Minerals in Layer S_(5-1) of Xifeng and Duanjiapo Sections
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作者 贾蓉芬 彭先芝 +3 位作者 周正 刘德汉 王冠鑫 王德强 《Chinese Journal Of Geochemistry》 EI CAS 2004年第3期197-206,共10页
Relatively strongly magnetic fine components (<30μm, XS-4J and DS-4J) which are most environmentally sensitive were separated from layer S-{5-1} in the Xifeng and Duanjiapo loess sections and analyzed by MPV-3 for... Relatively strongly magnetic fine components (<30μm, XS-4J and DS-4J) which are most environmentally sensitive were separated from layer S-{5-1} in the Xifeng and Duanjiapo loess sections and analyzed by MPV-3 for their morphometric characteristics and reflectance, SEM-ESD for their element contents and XRD for their mineral phases, respectively. The results showed that minerals in both samples are dominated by detrial Fe-Ti oxides of aeolian origin. In sample XS-4J the reflectance and iron contents of magnetic minerals are usually high. In addition to magnetite (Fe-3O-4), maghemite (γFe-2O-3) and hematite (Fe-2O-3), some Fe-high oxide ({72.25 wt%}-{86.67 wt%}), ilmenite (FeTiO-3), and magnetite-ulvspinel were also detected. In sample DS-4J obvious negative linear correlations were found between Ti and Fe, and the contents of Mn, Si, Al and Ca are usually high and the minerals are dominated by magnetite (maghemite), goethite (FeOOH) and limonite (containing Si and OH). In addition, the signs of corrosion of magnetic minerals and newly crystallized magnetite (maghemite) were recognized. Differences in the composition and assemblage characteristics of magnetite minerals between XS and DS reflect significant differences in source rocks and preserving conditions. 展开更多
关键词 磁性材料 黄土 古土壤 可结晶性 光学微观结构 物理性质
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LTE Cat.1物联网芯片物理层设计与开发
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作者 吴晓荣 《科学技术创新》 2024年第15期75-78,共4页
本文结合芯迈微半导体的Cat.1物联网芯片开发项目展开研究,首先简要介绍项目开发情况;然后重点阐述了物理层功能的软硬件协同开发流程、软硬件划分、ASIC设计的硬件资源与时序优化,以及功耗相关的软硬件设计;最后规划清晰的芯片验证路径... 本文结合芯迈微半导体的Cat.1物联网芯片开发项目展开研究,首先简要介绍项目开发情况;然后重点阐述了物理层功能的软硬件协同开发流程、软硬件划分、ASIC设计的硬件资源与时序优化,以及功耗相关的软硬件设计;最后规划清晰的芯片验证路径,有效暴露ASIC模块的设计问题。 展开更多
关键词 Cat.1 LTE通信芯片 通信物理层 芯片验证
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肠内菌群对人参皂苷Rg_1的代谢转化作用的研究 被引量:73
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作者 王毅 刘铁汉 +1 位作者 王巍 王本祥 《中国中药杂志》 CAS CSCD 北大核心 2001年第3期188-190,共3页
目的 :通过离体和整体实验研究大鼠及人的肠道内细菌对人参皂苷Rg1的代谢作用。方法 :用薄层层析及电喷雾质谱检测Rg1的代谢产物。结果 :Rg1在大鼠体内被代谢成一对同分异构体 (Rh1及F1)及苷元 [2 0(S)Protopanaxatriol,Ppt]。但在人的... 目的 :通过离体和整体实验研究大鼠及人的肠道内细菌对人参皂苷Rg1的代谢作用。方法 :用薄层层析及电喷雾质谱检测Rg1的代谢产物。结果 :Rg1在大鼠体内被代谢成一对同分异构体 (Rh1及F1)及苷元 [2 0(S)Protopanaxatriol,Ppt]。但在人的肠道内 ,则代谢物为Rh1及苷元。结论 :Rg1在人和大鼠肠内菌作用下均被代谢 ,但沿不同的代谢途径进行代谢。在大鼠体内 ,代谢模式为 :Rg1Rh1(F1)Ppt ;在人体内 ,代谢模式为Rg1Rh1Ppt。 展开更多
关键词 人参皂苷RG1 人参皂苷RH1 肠内菌群 电喷雾质谱 薄层层析
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金平1浅层大位移水平井钻井技术 被引量:28
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作者 裴建忠 刘天科 +1 位作者 周飞 王树永 《石油钻探技术》 CAS 北大核心 2009年第1期87-90,共4页
金平1井是胜利油田第一口特浅大位移水平井,创全国陆地油田水平井位垂比最高纪录(位垂比2.803∶1)。该井为预探井,钻进地层埋深浅,欠压实程度高,地层不稳定,上部地层松软,地层造斜能力差。通过优化井身结构设计、钻具组合与钻井参数,保... 金平1井是胜利油田第一口特浅大位移水平井,创全国陆地油田水平井位垂比最高纪录(位垂比2.803∶1)。该井为预探井,钻进地层埋深浅,欠压实程度高,地层不稳定,上部地层松软,地层造斜能力差。通过优化井身结构设计、钻具组合与钻井参数,保证了井眼轨迹平滑;利用摩阻扭矩计算软件进行实时摩阻扭矩分析,采用短起下钻、分段循环等手段有效清除了岩屑床,保障了井眼畅通和井下安全;采用乳化润滑防塌钻井液体系,根据地层特点合理调整钻井液性能,满足了全井井壁稳定、携岩和润滑的要求。全井克服了浅地层造斜稳斜控制困难,大井眼、长水平段岩屑携带困难,起下钻摩阻大,旋转钻进扭矩大等一系列技术难题,安全钻至井深2218m,水平位移1636.49m,垂深592.90m。详细介绍了金平1井的现场施工情况。 展开更多
关键词 浅层 大角度斜井 水平井 金平1
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H_2及H^+对C_xH_(1-x)薄膜表面状态的影响 被引量:29
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作者 吴卫东 罗江山 +7 位作者 黄勇 张占文 许华 郑永铭 陆晓明 唐永建 赵纯培 陈红 《强激光与粒子束》 EI CAS CSCD 北大核心 2000年第5期593-596,共4页
系统研究了 H2 流量和 H+原位处理 Cx H1-x薄膜的时间对 Cx H1-x薄膜的稳定时间、表面悬挂键密度和表面电子局域化程度的影响 ,表明 Cx H1-x薄膜的长时间 H+ 原位处理是减小 Cx H1-x薄膜表面悬挂键密度的有效途径。
关键词 薄膜 ICF靶涂层技术 氢分子 氢离子
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降脂1号口服液中芍药苷的含量测定 被引量:11
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作者 黎新荣 温宝仪 +1 位作者 李健群 曾环兵 《中国医院药学杂志》 CAS CSCD 北大核心 1999年第6期335-337,共3页
目的:对降脂1号口服液中芍药苷的定量方法进行研究,以控制制剂质量。方法:用薄层层析法鉴定芍药苷,以薄层扫描法测定制剂中芍药苷的含量。结果:所建立的方法能简便准确鉴定及有效地测定制剂中的芍药苷。结论:本法具有稳定、色谱... 目的:对降脂1号口服液中芍药苷的定量方法进行研究,以控制制剂质量。方法:用薄层层析法鉴定芍药苷,以薄层扫描法测定制剂中芍药苷的含量。结果:所建立的方法能简便准确鉴定及有效地测定制剂中的芍药苷。结论:本法具有稳定、色谱分离效果好。 展开更多
关键词 降脂1号口服液 芍药苷 含量 质量控制
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