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Influence of Size of Hematite Powder on Its Reduction Kinetics by H_2 at Low Temperature

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Journal of Iron and Steel Research International 2009年第5期16卷 7-11页

作者： PANG jian-ming GUO Pei-min ZHAO Pei cao Chao-zhen ZHANG Dian-wei The State Key Laboratory for Advanced Iron and Steel Processes and Materials Central Iron and Steel Research Institute Beijing 100081 China

The reduction kinetics and mechanisms of hematite ore with various particle sizes with hydrogen at low temperature were studied using the thermogravimetric analysis. At the same temperature, after the particle size of powder decreases from 107. 5μm to 2. 0 μm, the surface area of the powder and the contact area between the powder and gas increase, which makes the reduction process of hematite accelerate by about 8 times, and the apparent activation energy of the reduction reaction drops to 36.9 kJ/mol from 78. 3 kJ/mol because the activity of ore powder is improved by refining gradually. With the same reaction rate, the reaction temperature of 6.5 μm powder decreases by about 80 ℃ compared with that of 107. 5 μm powder. Thinner diffusion layer can also accelerate the reaction owing to powder refining. The higher the temperature, the greater is the peak of the reduction rate; at the same temperature, the greater the particle size, the smaller is the peak value of the reduction rate; both inner diffusion and interface chemical reaction play an important role in the whole reaction process.

关键词： iron oxide low temperature reduction kinetics thermogravimetric analysis (TGA), reduction mechanism

Properties of DR1/PMMA-co-GMA for High Speed Electro-optical Switch

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Chemical Research in Chinese Universities 2012年第6期28卷 1091-1094页

作者： cao Zi-jian JIN Lin WANG Xi-bin CUI Zhan-chen ZHANG Da-ming State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering State Key Laboratory of Superamolecular Structure and Materials Jilin University Changchun 130012 P. R. China

A non-linear optical（NLO） material was synthesized by means of a simple *** material can be applied in electro-optical（EO） devices,such as EO switches and *** Disperse Red 1（DR1） was doped in polymethyl-methacrylate-co-glycidyl methacrylate（PMMA-co-GMA） as the NLO active *** synthesis process and material structure were *** thermal properties,surface morphology and optical characteristics of the material were investigated by means of differential scanning calorimetry（DSC）,thermogravimetric analysis（TGA）,atomic force microscopy（AFM）,and m-lines *** the reflection technique,the value of the electro-optical coefficient γ 33 was measured as 11 pm/V at a wavelength of 1310 *** EO switch with nanosecond response based on this material has been fabricated.

关键词： Disperse Red 1/polymethyl-methacrylate-co-glycidyl methacrylate(DR1/PMMA-co-GMA) Electrooptical switch Thermal stability Optical property

Activation of Growth-associated Protein by Intragastric Brazilein in Motor Neuron of Spinal Cord Connected with Injured Sciatic Nerve in Mice

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Chemical Research in Chinese Universities 2011年第2期27卷 254-257页

作者： cao jian LI Li-sen LIU Biao LIU Hao-yu ZHANG Hui ZHAO ming-ming YIN Wei-tian China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China

The purpose of this study is to explore the expression of growth-associated protein（GAP-43） in spinal cord segments connected with injured sciatic nerve by the treatment with brazilein in mice. Unilateral sciatic nerve interruption and anastomosis were performed. Physiological saline（blank group）, high dose, middle dose and low dose of brazilein were administrated intragastrically to healthy adult BALB/c mice in separate groups. L4―6 spinal segments connected with the sciatic nerve were harvested. Real-time PCR（Polymerase chain reaction） and Western blot analysis were performed to detect the expression of GAP-43 in spinal segments. Histological staining on myelin and the electrophysiology were performed to examine the sciatic nerve recovery. GAP-43 was activated in spinal cord L4―6 connected with injured sciatic nerve. In the survival time of 12 h, 24 h, 3 d, 5 d, 7 d and 14 d, GAP-43 expression in the motor neurons of spinal cord of the high dose group and that in the middle dose group were significantly higher than those on the low dose and blank groups. Myelin in the high dose group and that in the middle dose group were more mature and the potential amplitude and MNCV（motor nerve conduction velocity） in the high and middle dose groups were obviously higher than those in the low dose group and blank group. Brazilein facilitates the expression of GAP-43 in neurons in spinal cord L4―6 segments connected with injured sciatic nerve, which promotes nerve regeneration.

关键词： Brazilein Growth-associated protein(GAP-43) Injury of sciatic nerve Regeneration

丹酚酸B调控脂质代谢改善非酒精性脂肪肝实验研究

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中国药理学通报 2025年第1期41卷 107-115页

作者：张佳健郭梦茹梅金玉陈明安徽医科大学基础医学院药理学教研室安徽合肥230032 安徽医科大学第二附属医院耳鼻喉科安徽合肥230601

目的探讨丹酚酸B(SalB)可能通过调控Lcn2改善非酒精性脂肪肝的作用。方法体内实验,8周龄♂C57BL/6J小鼠用普通维持饲料喂养,作为对照组,8周龄ApoE-/-小鼠用高脂饲料喂养,随机分为模型组和SalB组。在饲养8周后,SalB组小鼠用SalB灌胃,低... 详细信息

目的探讨丹酚酸B(SalB)可能通过调控Lcn2改善非酒精性脂肪肝的作用。方法体内实验,8周龄♂C57BL/6J小鼠用普通维持饲料喂养,作为对照组,8周龄ApoE-/-小鼠用高脂饲料喂养,随机分为模型组和SalB组。在饲养8周后,SalB组小鼠用SalB灌胃,低剂量为15 mg·kg^(-1)·d^(-1),高剂量为30 mg·kg^(-1)·d^(-1),对照组和模型组用等剂量生理盐水灌胃。肝脏转录组测序结果揭示模型组和SalB组的差异表达基因,HE染色、油红O染色观察肝组织的病理变化,试剂盒检测血清和肝组织的脂质、氧化应激和炎症指标,RT-qPCR检测Lcn2、SREBP-1C以及脂质合成相关酶的mRNA水平。体外实验,用棕榈酸(PA)诱导L02和LX-2细胞24 h建立NAFLD模型,用SalB(30μmol·L^(-1))和PA(0.2 mmol·L^(-1))共孵育检测SalB体外改善NAFLD的情况。试剂盒检测L02细胞TC、TG的含量,细胞油红O染色试剂盒检测L02细胞的脂质积累,RT-qPCR检测LX-2细胞Lcn2、SREBP-1C以及脂质合成相关酶基因的mRNA水平。结果模型组血清、肝脏的生化指标异常,肝组织脂质、炎症和氧化应激水平升高,出现大面积脂肪空泡和大量的脂质沉积,PA诱导的L02细胞也出现大量的脂质积累,在SalB干预后均有明显改善。转录组测序结果表明SalB可以调控肝脏脂质代谢和炎症。肝脏和LX-2细胞mRNA水平显示模型组Lcn2、SREBP-1C以及脂质合成相关酶基因表达明显上调,SalB干预后均能降低这些基因的表达。结论丹酚酸B可以明显改善非酒精性脂肪肝,其机制可能是通过下调Lcn2、SREBP-1C和脂质合成酶的表达。

关键词： SalB 非酒精性脂肪肝脂质代谢 Lcn2 SREBP-1C 脂质合成相关酶

3D-QSAR Studies on the Imidazopyrimidine Derivatives

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Chinese Journal of Structural Chemistry 2020年第11期39卷 1985-1989页

作者： TONG jian-Bo cao Xu Shaanxi Key Laboratory of Chemical Additives for Industry Shaanxi University of Science and TechnologyXi'an 710021China

Comparative molecular field analysis(CoMFA) and comparative molecular similarity indices analysis(CoMSIA) for imidazopyrimidine derivatives were performed to get the molecular active conformation selection, molecular alignment, as well as the establishment of corresponding 3 D-QSAR model. The model established by this method has good ability to predict such compounds. For CoMFA model, the cross-validated q2 and non-cross-validated r2 values are 0.665 and 0.872, respectively. The best q2 value for CoMSIA model is 0.632 and r2 value is 0.923. Using this information and the three-dimensional equipotential map for molecular design can theoretically obtain some new antibacterial drugs with higher activity. There are two newly designed molecules with activity values of 7.921 and 7.872, which are higher than that of the template molecule No. 12 with an activity value of 7.850, and the QSAR research results can provide a theoretical reference for the synthesis of new drugs.

关键词： 3D-QSAR comparative molecular force field analysis molecular design

The investigation on strain of SiGe/Si heteroepitaxial system during high temperature annealing by RBS/Channeling

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The investigation on strain of SiGe/Si heteroepitaxial syste...

Effects of Al contents on microstructure and properties of hot-dip Zn-Al alloy coatings on hydrogen reduced hot-rolled steel without acid pickling

'2001全国荷电粒子源、粒子束学术会议

作者： CHEN Chang-Chun 1, ZHU De-Zhang 1, ZHANG Shi-Li 2, LIU Hua-ming 1, cao jian-Qin 1, ZHANG Zhi-Bin 1, PAN Hao-Chuang 1 and WANG Yong-Qi 11. Laboratory of Nuclear Analyses and Techniques, Shanghai institute of nuclear research, P. 0. BOX 800-204, Chinese Academy of Sciences, Shanghai 201800, China2. Kungliga Tekniska Hogskolan, Department of Electronics, Electrum 229, SE-16440 Kista, Sweden

The influence of the high temperature processing on strain stored in SiGehetero-epilayer was studied by means of RBS/*** angular scanalong the axial direction in the(100) plane was used to characterize thetetragonal distortion in SiGe strained *** strained crystal structureparameters can be acquired by combining the determination of strain with theelasticity *** is shown that the strain stored in the SiGe epilayer hassignificantly change(relaxation factor from 0.023 to 0.84) after high *** potential strain relaxation mechanisms were discussed.

关键词： The investigation on strain of SiGe/Si heteroepitaxial system during high temperature annealing by RBS/Channeling RBS

来源： cnki会议评论

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Journal of Iron and Steel Research International 2017年第10期24卷 1032-1040页

作者： Zhi-feng Li Yong-quan He Guang-ming cao Jun-jian Tang Xiang-jun Zhang Zhen-yu Liu State Key Laboratory of Rolling and Automation Northeastern University School of Mechatronics Engineering Zhengzhou University of Aeronautics

A new hot-dip galvanizing method was employed on hot-rolled low carbon *** effects of Al contents on microstructure,micro-hardness and corrosion resistance of Zn-Al alloy coatings were systematically *** composition,microstructure and element distribution in Zn-Al alloy coatings were analyzed using X-ray diffraction（XRD）and electron probe micro analysis（EPMA）,*** is found that Al content（0.6-6.0 wt.%）in galvanizing zinc affects surface quality and adhesion between coatings and matrix in the newly developed *** addition,with increasing Al content,micro-hardness significantly increased due to the increase in Zn-Al eutectoid *** polarization and electrochemical impedance spectroscopy（EIS）also revealed that increase in Al plays a noticeable role in improving the corrosion resistance of Zn-Al alloy coatings.

关键词： Hot-rolled steel strip Hydrogen reduction Eutectoid structure Micro-hardnessCorrosion resistance Zn-Al alloy coating

SAR image denoising based on wavelet-fractal analysis

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Journal of Systems Engineering and Electronics 2007年第1期18卷 45-48页

作者： Zhao jian cao Zhengwen Zhou mingquan School of Electronics and Information Northwestern Polytechnical Univ. Xi'an 710072 E R. China School of Information Science and Technology Northwest Univ. Xi'an 710069 E R. China

Wavelet-fractal based SAR （synthetic aperture radar） image processing is one of the advanced technologies in image processing. The main concept of analysis is that after wavelet transformation, multifractal spectrum of the signal is different from that of noise. This difference is used to alleviate the noise produced by SAR *** method to denoise SAR image using the process based on wavelet-fractai analysis is discussed in detail. Essentially, the present method focuses on adjusting the Hoelder exponent α of multifractal spectrum. After simulation, α should be adjusted to 1.72-1.73. The more the value of α exceeds 1.73, the less distinctive the edges of SAR image become. According to the authors denoising is optimal at α=1.72-1.73. In other words, when α =1.72-1.73, a smooth and denoised SAR image is produced.

关键词： Synthetic aperture radar image Wavelet Multifractal analysis Denoising Hoelder exponent

Electrochemical Behavior of CoSb_3-based Electrodes Using Binary PAni/PVDF Binder

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Journal of Materials Science & Technology 2007年第1期23卷 142-144页

作者： jian XIE Xinbing ZHAO Gaoshao cao Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

The polyaniline （PAni）/polyvinylidene fluoride （PVDF） hybrid was served as a novel binder for CoSb3-based alloy electrode. The effect of PAni content on the electrochemical performances of the alloy electrode was investigated. It was found that the CoSb3 electrode using the binary PAni/PVDF binder exhibits higher reversible capacity than that using the single PVDF binder, especially in the initial cycles. As a result, the PAni/PVDF hybrid could be a promising binder for the alloy electrode.

关键词： PAni/PVDF binder CoSb3 electrode Electrochemical behavior Lithium ion batteries