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RELATIONSHIP OF HOMOCYSTEINE AND GENE POLYMORPHISMS OF ITS RELATED METABOLIC ENZYMES WITH ALZHEIMER'S DISEASE

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Chinese Medical Sciences Journal 2005年第4期20卷 247-251,页

作者： Ying-dong zhang Xiao-yan ke wei Shen Yang Liu Neuropsychiatric Institute Nanjing Brain Hospital Nanjing Medical University Nanjing 210029

Objective To investigate the relationship of plasma homocysteine (Hcy) levels and the gene polymorphisms of N5, N10-methylenetetrahydrofolate reductase (MTHFR), cystathionine β-synthase (CBS) with Alzheimer’s disease (AD). Methods Plasma Hcy levels were measured by means of high voltage capillary electrophoresis with ultra-violet detection, the polymorphisms of C677T in exon 4 of MTHFR gene and 844ins68 in exon 8 of CBS gene were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 105 AD patients and 102 non-AD controls. All controls were excluded from cardiocerebrovascular disorders and other diseases. Results The plasma Hcy level in AD patients (16.04 ± 3.84 μmol/L) was significantly higher than that in the controls(11.94 ± 3.87 μmol/L, P < 0.001). There were no significant differences of the genotype and allele frequencies of MTHFR C677T mutation and CBS 844ins68 mutation between the patients and controls. However, the T allele of MTHFR gene was found to relate with the plasma Hcy level increase in all subjects. Conclusion The elevated plasma Hcy level in AD patients is probably involved in the pathogenesis of AD, which may be due to the environmental factor rather than genetic factors of the mutations of MTHFR and CBS.

关键词： Alzheimer's disease homocysteine N^5, N^10-methylenetetrahydrofolate reductase cystathionine [3-synthase

NUMERICAL RESEARCH ON WATER GUIDE BEARING OF HYDRO-GENERATOR UNIT USING FINITE VOLUME METHOD

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Journal of Hydrodynamics 2007年第5期19卷 635-642页

作者： PENG Yu-cheng CHEN Xi-yang zhang ke-wei HOU Guo-xiang School of Energy and Power. Engineering Huazhong University of Science and Technology Wuhan 430074 China School of Traffic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

With the consideration of the geometry of tilting pad journal bearing, a new form of the Reynolds equation was derived in this article. The film thickness, the squeeze motion of the journal and the rotation motion of the pad were explicitly contained in the equation. Based on this equation, together with the equilibrium equation of pad pivot, the water guide bearing used in the Gezhouba 10 F hydro-generator unit was numerically researched. The new Reynolds equation for the lubricating film was solved using Finite Volume （FV） discretization, Successive Over-Relaxation （SOR） iteration method and C＋＋ code are included. According to the numerical solution, and the stability of the film and the influences of the film thickness, the journal squeeze effect and the pad rotation effect on film force were discussed. The results indicate that the squeeze effect can not be neglected, although the rotation effect is negligible for both low-speed and high-speed bearings, so the computing time could be greatly reduced.

关键词： hydro-generator unit Reynolds equation,tilting pad journal bearing Finite Volume (FV) method

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 246-257页

作者： zhang Jian NIE wei HUANG Jin ZHU ke LIU Ruxia zhang Ruizhi LUO Guoqiang SHEN Qiang State key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

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优化式着色算法的混色机制

电子与信息学报 2013年第7期35卷 1612-1618页

作者：张可为申群太中南大学信息科学与工程学院长沙410008 湖南工程学院电气信息学院湘潭411101

基于局部关系模型的优化式着色方式,难以定量描述其全局特性信息诸如着色结果与用户输入间关系。该文首先提出一种优化式着色框架,证明两种常用算法为其特例而且等价,然后将每个像素的着色结果转化为各涂抹颜色的组合形式,并通过数学分... 详细信息

基于局部关系模型的优化式着色方式,难以定量描述其全局特性信息诸如着色结果与用户输入间关系。该文首先提出一种优化式着色框架,证明两种常用算法为其特例而且等价,然后将每个像素的着色结果转化为各涂抹颜色的组合形式,并通过数学分析推导出组合系数非负且归一化,从而证明优化着色具有混色机制,其结果由涂抹颜色混色而成,并推导出混色权重与首达概率的等价性,最后基于混色机制对现有算法提出改进。实验结果表明混色机制的引入既有助于提高着色效果对涂抹数量与位置的鲁棒性,也便于实时挑选涂抹颜色。

关键词：图像处理优化式着色数学分析算法等价混色

Melting Evaluation of Phase Change Materials Impregnated into Cascaded Metal Foams with Regionalized Enhancement

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Journal of Thermal Science 2025年第1期34卷 223-241页

作者： wei Xinyi zhang Nan zhang Zhaoli CAO Xiaoling YUAN Yanping School of Mechanical Engineering Southwest Jiaotong University

Metal foam promotes the heat transfer of phase change materials(PCMs) in the penalty of reducing the energy storage density of the composite *** this work,the effects of constant porosity(0.96,0.94,0.92,or 0.90) and pore density(PPI) of metal foam on heat transfer of composite PCMs are *** rate could be enhanced by employing with low porosity copper ***,aiming to the right bottom phase changing "dead region",a regionalized enhancement strategy of cascaded metal foams is *** dynamic melting performances of all the composite PCMs are comprehensively *** results reveal that the cascaded configuration is beneficial for *** show that the horizontal strategy enhances melting performance:a maximum of 17.98% reduction in total melting time could be reached when the rear part porosity is 90%.The energy storage density rate could be raised by 5.48%.Besides,the vertical strategy performs with a better average temperature uniformity of 0.441 and brings a lower temperature in the heated *** sum up,the regionalized enhancement of copper foam provides better performance in the phase change *** shows significant potential for solar heat storage and thermal protection.

关键词： copper metal foam heat transfer enhancement phase change materials regionalized enhancement

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一种改进的AprioriTid算法

沈阳工业大学学报 2016年第3期38卷 314-318页

作者：张伟科沈阳理工大学理学院沈阳110159

针对经典Apriori算法多次扫描数据库产生I/O负载影响运行效率等问题,在对Apriori算法的原理及其相关改进算法研究的基础上,提出了一种基于压缩集的改进Apriori算法,即Apriori Tid_M算法.通过有效的裁剪方法减少无效项集的产生,减少候选... 详细信息

针对经典Apriori算法多次扫描数据库产生I/O负载影响运行效率等问题,在对Apriori算法的原理及其相关改进算法研究的基础上,提出了一种基于压缩集的改进Apriori算法,即Apriori Tid_M算法.通过有效的裁剪方法减少无效项集的产生,减少候选项集的数量,从而提高算法的效率.仿真实验表明,在支持度相同但数据量不同,以及数据量相同但支持度不同这两种条件下,Apriori Tid_M算法在性能上和运算时间上都比Apriori算法有很大程度的改善.

关键词： Apriori算法 AprioriTid算法 AprioriTid_M算法关联规则置信度项集支持度性能

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药品犯罪刑事司法治理模式的实践检视

北京社会科学 2023年第12期 79-92页

作者：张伟珂中国人民公安大学法学院

通过对药品犯罪司法惩治现状的梳理,发现既往犯罪治理的重点在销售端,对生产行为与帮助行为的查处有限;司法认定中偏重缺陷药品的形式评价,而对药品危险性的实质评价不足;量刑环节报应色彩较重,弱化了刑罚预防功能。在《刑法修正案(十一... 详细信息

通过对药品犯罪司法惩治现状的梳理,发现既往犯罪治理的重点在销售端,对生产行为与帮助行为的查处有限;司法认定中偏重缺陷药品的形式评价,而对药品危险性的实质评价不足;量刑环节报应色彩较重,弱化了刑罚预防功能。在《刑法修正案(十一)》生效以后,这种传统治理模式难以适应缺陷药品性质评价复杂化、缺陷药品证据认定标准复杂化、犯罪故意司法认定复杂化的挑战。为此,应当拓宽缺陷药品的证明方式,通过司法推定的反驳机制,合理限制主观明知的司法扩张,限缩妨害药品管理罪中具体危险的判断规则,加强对缺陷药品的源头治理,强化刑罚的特殊预防效果。

关键词：药品犯罪刑事犯罪妨害药品管理罪司法治理

运用离子选择性电极研究氟离子与蛋白质的相互作用

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化学学报 2008年第1期66卷 10-14页

作者：卢雁王公轲张玮玮河南师范大学化学与环境科学学院新乡453007

在醋酸-醋酸钠缓冲溶液中(pH=5.68),运用氟离子选择性电极研究了288～308K时F-与牛血清蛋白(BSA)、牛血红蛋白(BHb)和卵清蛋白(OVA)的相互作用.F-和3种蛋白质相互作用体系的实验数据通过Klotz方程进行处理,得到了很好的线性关系,根据拟... 详细信息

在醋酸-醋酸钠缓冲溶液中(pH=5.68),运用氟离子选择性电极研究了288～308K时F-与牛血清蛋白(BSA)、牛血红蛋白(BHb)和卵清蛋白(OVA)的相互作用.F-和3种蛋白质相互作用体系的实验数据通过Klotz方程进行处理,得到了很好的线性关系,根据拟合的直线得到了F-在3种蛋白分子上的束缚位点数以及相应的束缚常数.结果表明,F-在BSA和BHb分子上的束缚位点数随着温度的升高而增大,而在OVA分子上的束缚位点数随着温度的升高而减小.另外,F-与BSA和BHb作用的束缚常数随着温度的升高,先减小后增大;而与OVA的束缚常数则表现出相反的规律,即先增大后减小.根据蛋白质分子二级结构的差别,对上述现象进行了合理的解释.运用热力学方程计算出了不同温度下每个束缚过程的热力学函数(△G,△H,△S),说明F-和蛋白质分子之间主要依靠静电作用力相结合.

关键词：离子选择性电极氟离子牛血清蛋白牛血红蛋白卵清蛋白束缚

不同形貌Bi2WO6/CNOs复合材料的电化学性能研究

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人工晶体学报 2019年第12期48卷 2265-2269页

作者：张涛张卫珂太原理工大学环境科学与工程学院太原030000 山东省科学院新材料研究所济南250014

低污染、高能量的超级电容器是目前研究的重点。本文利用水热法合成了Bi2WO6/CNOs复合材料,并通过改变前驱体的pH值来调整复合材料的形态,在pH值为3和11的条件下合成了花状片层结构和块状结构的复合材料,并将其作为赝电容的电极材料。... 详细信息

低污染、高能量的超级电容器是目前研究的重点。本文利用水热法合成了Bi2WO6/CNOs复合材料,并通过改变前驱体的pH值来调整复合材料的形态,在pH值为3和11的条件下合成了花状片层结构和块状结构的复合材料,并将其作为赝电容的电极材料。采用循环伏安法、恒电流充放电法和电化学阻抗法研究了制备的Bi2WO6/CNOs复合材料的电化学性能。结果表明,在电流密度为10 mA/cm^2时,以1 mol/L KOH溶液为电解液的条件下,pH=3时花状片层结构的Bi2WO6/CNOs复合材料的比电容为152.7 F/g,大于pH=11时复合材料的比电容。这主要是由于CNOs能均匀分散在Bi2WO6的片层之间,从而起到良好的支撑和电子传输作用。

关键词： Bi2WO6 纳米洋葱碳赝电容形貌