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RESEARCH ON IMPROVED CUT-OFF NEGATIVE PRESSURE METHOD FOR UNSTEADY SEEPAGE FLOW WITH FREE SURFACE

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Journal of Hydrodynamics 2005年第5期17卷 521-531页

作者： ZHANG Qian-fei wang yan-ming Shanghai Municipal Engineering Design Institute Shanghai 200092 China

The cut-off negative pressure method is one of effective approaches to solve the seepage flow with free surface. According to the characteristics of this method, however, it has been found out that the deficiency of the algorithms is to easily cause inaccurate simulation in the vicinity of free surface owing to the penalty function with only one controlling penalty parameter. Therefore, an improved cut-off pressure method was presented by constructing penalty function with two controlling penalty parameters. The improved algorithms were illustrated to be able to improve the simulation accuracy and raise the convergence speed through considering the effects of the partially saturated or unsaturated elements more reasonably and calculating the nodal external forces more accurately. Finally, the improved cut-off negative pressure method was applied to the simulation of unsteady seepage flow with free surface, and the corresponding program codes were developed with validation of some cases.

关键词： free surface unsteady seepage flow finite element method improved cut-off negative pressure method

基于机械剥离制备的PEDOT:PSS/β-Ga_(2)O_(3)微米片异质结紫外光电探测器研究

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物理学报 2024年第15期73卷 172-178页

作者：宜子琪王彦明王硕隋雪石佳辉杨壹涵王德煜冯秋菊孙景昌梁红伟辽宁师范大学物理与电子技术学院大连116029 大连理工大学集成电路学院大连116024

β-Ga_(2)O_(3)具有超宽带隙(约4.9 eV)、高的击穿电场(约8 MV/cm)、良好的化学稳定性和热稳定性等优点,是一种很有前途的制备紫外光电探测器的候选材料.由于未掺杂的β-Ga_(2)O_(3)为n型导电,所以制备p型β-Ga_(2)O_(3)面临很多困难,... 详细信息

β-Ga_(2)O_(3)具有超宽带隙(约4.9 eV)、高的击穿电场(约8 MV/cm)、良好的化学稳定性和热稳定性等优点,是一种很有前途的制备紫外光电探测器的候选材料.由于未掺杂的β-Ga_(2)O_(3)为n型导电,所以制备p型β-Ga_(2)O_(3)面临很多困难,从而制约了同质PN结的开发与应用.聚(3,4-乙烯二氧噻吩)-聚苯乙烯磺酸(PEDOT:PSS)是一种p型导电聚合物,在250—700 nm有着较高的透明度,采用p型有机材料PEDOT:PSS和n型β-Ga_(2)O_(3)构成的异质结可能为PN结型光电器件的研制提供一种途径.本文利用机械剥离法从β-Ga_(2)O_(3)单晶衬底上剥离出单根β-Ga_(2)O_(3)微米片,微米片的长度为4 mm,宽度为500μm,厚度为57μm.将有机材料PEDOT:PSS涂覆在剥离出来的微米片的一侧制备出PEDOT:PSS/β-Ga_(2)O_(3)无机-有机异质结的紫外光电探测器,器件表现出典型的整流特性,而且发现器件对254 nm紫外光敏感,具有良好的自供电性能.该异质结紫外探测器的响应度和外量子效率分别为7.13 A/W和3484%,上升时间和下降时间分别为0.25 s和0.20 s.此外,3个月后器件对254 nm紫外光的探测性能并未发现明显的衰减现象.本文的相关研究工作将对研发新型紫外探测器提供了新的思路和理论基础.

关键词： β-Ga_(2)O_(3) PEDOT:PSS 异质结紫外光电探测器

Capillary electrophoresis with direct chemiluminescence detection for the analysis of catecholamines in human urine

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Chinese Chemical Letters 2007年第4期18卷 452-454页

作者： Cheng Quan wang Hui wang yan ming Liu College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang 464000 China

A rapid and sensitive method for the analysis of three catecholamines by capillary electrophoresis （CE） with direct chemiluminescence （CL） detection is described. The detection limits （S/N= 3） were 1.3 × 10^-8 g/mL for isoprenaline, 1.0 × 10^-8g/mL for epinephrine and 2.8 × 10^-8 g/mL for dopamine. The proposed method was successfully applied to the analysis of catecholamines in urine samples of cigarette smokers and nonsmokers. The results showed that there is a close relation between the release of dopamine in human body fluids and cigarette smoking/nonsmoking.

关键词： Capillary electrophoresis Catecholamines Chemiluminescence detection Urine

经阴道三维超声参数及血清VEGF、TIMP-1水平与宫腔粘连程度的相关性

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四川生理科学杂志 2024年第10期46卷 2192-2194,2247页

作者：姚娟张悦王燕铭周口骨科医院超声医学科河南周口466000 周口市妇幼保健院(周口市儿童医院)超声科河南周口466000 湖州学院附属南太湖医院超声科河南湖州313000

目的:探究经阴道三维超声(Transvaginal three-dimensional ultrasound,3D-TVS)参数、血清血管内皮细胞生长因子(Vascular endothelial cell growth factor,VEGF)、基质金属蛋白酶抑制因子-1(Matrix metalloproteinase inhibitor-1,TIMP-1)与宫腔粘连程度的相关性。方法:收集2022年6月至2023年6月于我院就诊的76例宫腔粘连患者为粘连组,另选76例子宫内膜正常患者为对照组,比较2组、不同粘连程度患者3D-TVS参数及血清VEGF、TIMP-1水平,分析相关性及诊断价值。结果:两组3D-TVS参数及血清VEGF、TIMP-1水平存在明显差异(P<0.05);血清VEGF、TIMP-1水平随宫腔粘连程度加重升高,3D-TVS参数随宫腔粘连程度加重降低(P<0.05);宫腔粘连严重程度与3D-TVS参数呈负相关,与血清VEGF、TIMP-1水平呈正相关(P<0.05);3D-TVS参数、血清VEGF、TIMP-1水平联合诊断中度、重度宫腔粘连AUC为0.920、0.947。结论:3D-TVS参数联合血清VEGF、TIMP-1水平与宫腔粘连程度关系密切,且诊断价值较高。

关键词：经阴道三维超声参数血管内皮细胞生长因子基质金属蛋白酶抑制因子-1 宫腔粘连联合诊断

Assembling and releasing performance of supramolecular hydrogels formed from simple drug molecule as the hydrogelator

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Chinese Chemical Letters 2007年第8期18卷 1009-1012页

作者： Yu Jiang wang Liang yan Li ming Tang Jian Yu Laboratory of Advanced Materials Department of Chemical Engineering Tsinghua University Beijing 100084 China

A simple drug compound, 4-oxo-4-（2-pyridinylamino） butanoic acid （defined as AP）, was able to gel water at 4 wt% concentration under various conditions. In the superstructure, AP molecules assembled into fibrous aggregates driving by hydrogen bonds and π-π stacking interaction. The gels with different backbone structures released drug molecules in different speeds.

关键词： Supramolecular hydrogel Hydrogelator Releasing

Ionic liquid-assisted synthesis of silver nanorods by polyol reduction

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Chinese Chemical Letters 2010年第7期21卷 872-875页

作者： Hong Ying wang yan An Gao ming Wei Zhao Li Qiang Zheng Key Laboratory of Colloid and Interface Chemistry of Ministry of Education in Shandong University Jinan 250100China

Silver nanorods have been successfully synthesized in large scale by the ethylene glycol（EG） reduction in the presence of ionic liquid（IL） 1-butyl-3-methylimidazolium tetrafluoroborate（bmimBF_4） and polyvinyl-pyrrolidone（PVP）.The silver nanorods were characterized by scanning electron microscopy（SEM）,high-resolution transmission electron microscopy（HRTEM）,transmission electron microscopy（TEM）,electron energy disperse spectroscopy（EDS） and UV-vis *** results showed that the uniform silver nanorods have an average diameter of about 100 nm and the aspect ratio from 15 to ***,bmimBF_4 may play a role of capping agent together with PVP in the formation of silver *** the other band,bmimBF_4 may accelerate nucleation and improve the stability of the resulting Ag nanorods due to the low interface tension of IL.

关键词： Silver nanorods Ionic liquid Ethylene glycol Capping agent

Growth process,defects,and dopants of bulkβ-Ga_(2)O_(3)semiconductor single crystals

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China Foundry 2024年第5期21卷 491-506页

作者： yan-shen wang ming-zhi Zhu Yuan Liu School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Beijing 100084China

β-gallium oxide(β-Ga2O3),as the typical representative of the fourth generation of semiconductors,has attracted increasing attention owing to its ultra-wide bandgap,superior optical properties,and excellent tolerance to high temperature and *** to the single crystals of other semiconductors,high-quality and large-sizeβ-Ga_(2)O_(3)single crystals can be grown with low-cost melting methods,making them highly *** this review,the growth process,defects,and dopants ofβ-Ga_(2)O_(3)are primarily ***,the growth process(e.g.,decomposition,crucible corrosion,spiral growth,and development)ofβ-Ga_(2)O_(3)single crystals are summarized and compared in ***,the defects ofβ-Ga_(2)O_(3)single crystals and the influence of defects on Schottky barrier diode(SBD)devices are emphatically ***,the influences of impurities and intrinsic defects on the electronic and optical properties ofβ-Ga_(2)O_(3)are also briefly *** this comprehensive analysis,the article offers a concise summary of the current state,challenges and prospects ofβ-Ga_(2)O_(3)single crystals.

关键词： β-Ga_(2)O_(3) single-crystal growth defects dopants semiconductor

双黄连口服液对H9亚型禽流感的预防和治疗效果

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动物医学进展 2024年第9期45卷 127-132页

作者：朱巧艳聂春波张盼涛薛瑞王锐王艳鸣赵青森李新乐高彬文赵坤坤洛阳中科基因检测诊断中心有限公司河南洛阳471000 徐州天意药业股份有限公司江苏徐州221000 北京中科基因技术股份有限公司北京102600

为了评价双黄连口服液对H9亚型禽流感的预防和治疗效果,分别在SPF鸡感染H9亚型禽流感病毒前和感染后口服双黄连口服液,病毒感染后3、5、7、10 d采集喉头和泄殖腔棉拭子,通过实时荧光定量RT-PCR检测排毒率,并在感染后5、7 d剖检观察组织... 详细信息

为了评价双黄连口服液对H9亚型禽流感的预防和治疗效果,分别在SPF鸡感染H9亚型禽流感病毒前和感染后口服双黄连口服液,病毒感染后3、5、7、10 d采集喉头和泄殖腔棉拭子,通过实时荧光定量RT-PCR检测排毒率,并在感染后5、7 d剖检观察组织病变,进行病理组织学观察。结果显示,双黄连口服液可降低H9亚型禽流感病毒感染鸡的排毒率,缩短排毒周期,治疗组和预防治疗组病毒感染后10 d排毒率为0,极显著低于病毒感染组排毒率6/10(60%)(P<0.01);治疗组和预防治疗组SPF鸡在感染后5 d和7 d喉头、气管黏膜、肺脏的组织损伤较小;且与治疗组相比,预防治疗组排毒率更低,喉头、气管、肺脏组织病理损伤更轻微。结果表明,双黄连口服液不仅可降低感染鸡的排毒率,缩短鸡体排毒时间。针对呼吸道病原,双黄连口服液预防治疗效果优于感染后治疗效果。该研究为双黄连口服液更好地应用于临床呼吸道疫病的防控提供了新的策略。

关键词：双黄连口服液 H9亚型禽流感预防和治疗排毒率组织病理学

微生物燃料电池耦合光催化技术降解葡萄酒清洗废水研究

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当代化工 2024年第1期53卷 63-67,72页

作者：张秀丽王延明李春虎青岛工程职业学院山东青岛266111 中国海洋大学山东青岛264200

光催化耦合微生物降解技术,在微生物代谢后期,污水中COD下降到光催化剂反应的范围,利用光能激发催化反应,将有机物质氧化成活性基团,可以将水体中难降解的有机物分解。以碳棒作为阳极,以碳布材料作为阴极,以负载TiO_(2)的活性炭作为生... 详细信息

光催化耦合微生物降解技术,在微生物代谢后期,污水中COD下降到光催化剂反应的范围,利用光能激发催化反应,将有机物质氧化成活性基团,可以将水体中难降解的有机物分解。以碳棒作为阳极,以碳布材料作为阴极,以负载TiO_(2)的活性炭作为生物载体,构建微生物燃料电池体系。葡萄酒废水酸性环境下微生物的生长缓慢,当阳极底物质量浓度由1000 mg·L^(-1)增大到3000 mg·L^(-1)时,COD去除率由较低水平的67%增大到较高水平的92%。在一定范围内,随着阳极底物质量浓度的增加,COD的去除率也有所增加。当阳极底物质量浓度由3000 mg·L^(-1)增大到4500 m·L^(-1)时,COD去除率由92%减小到81%,光催化的引入对处理低浓度的氨氮、总磷和COD效果均高于90%。

关键词： COD降解生物催化反应输出电压光催化活性