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Methods for Thickness Determination of SiC Homoepilayers by Using Infrared Reflectance Spectroscopy

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Chinese Physics Letters 2010年第6期27卷 240-243页

作者： LI Zhi-yun SUN ji-wei ZHANG yu-Ming ZHANG Yi-Men TANG Xiao-Yan Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices School of Microelectronics Xidian University Xi'an 710071

Infrared reflectance spectra have been widely used to measure layer thickness based either on calculation or on curve fitting, and two traditional methods for thickness determination have been studied. Considering the disadvantages of those two methods, we propose a new fitting model based on the fitting of the fringe order difference. In comparison with the measured results, the new fitting model shows its superiority not only for its stable and accurate results which have great agreement with the results from SEM, but also for its simple and quick fitting process.

关键词： THICKNESS measurement SILICON carbide INFRARED spectroscopy CURVE fitting COMPARATIVE studies SCANNING electron microscopy

Influence of CD133^+ expression on patients' survival and resistance of CD133^+ cells to anti-tumor reagents in gastric cancer

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Asian Pacific Journal of Tropical Biomedicine 2015年第12期5卷 996-1004页

作者： De-Hu Chen Rui-Qi Lu Xiao-Chun Ni Ju-Gang Wu Shou-Lian Wang Bo-jian jiang ji-wei yu Department of General Surgery Third People's Hospital Shanghai Jiao Tong University School of Medicine

Objective:To investigate the influence of CD133+expression on patients'survival and resistance of CD133+cells to anti-tumor agents in gastric cancer(GC).Methods:Influence of CD133 expression on prognosis was analyzed employing samples from patients with *** cell lines were utilized to separate CD133+and CD133-subpopulations by immunomagnetic separation and to analyze the biological features of two subpopulations in vitro and in vivo,especially in resistant to anti-tumor reagents and its apoptotic ***:The lower CD133+group showed a significantly better survival compared with the higher CD133+*** highest content of CD133+subpopulations for KATO-III cells had stronger proliferative ability than CD133-subpopulations.A single CD133+cell was capable of generating new cell colony and the tumorigenicity rate in nude mice was100%for CD133+clonal spheres or for CD133+cells,but 0%for ***,the higher expression levels of Oct-4,Sox-2,Musashi-1 and ABCG2 in CD133+clonal spheres were identified compared with CD133+cells or *** the treatment of anti-tumor reagents,CD133+cells had lower suppression rates compared with CD133-cells while lower level of Bcl-2 and higher level of Bax were found in CD133+cells compared with ***:The patients with lower CD133+expression had a better *** CD133+cells in clonal sphere shared the ability to be self-renewable,proliferative,tumorigenic and resistant to anti-tumor agents as probably regulated by Bcl-2 and Bax.

关键词： Stomach Cancer CD133 Tumor initiating cells

The Application and Prospect of Stabilization/Solidification Technology for Hazardous Waste in China

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科技信息 2011年第27期 I0018-I0019页

作者： WANG ji-wei ZHANG Pei-yu CHEN Shu ZHENG Meng Environmental Science and Engineering Department of Qingdao University Qingdao Shandong 266071

The number of hazardous waste in our country increased dramatically in recent years,stabilization/solidification technology begins to attract a wide spread attention by domestic *** on the domestic related literature,this paper discussed the present situation about the treatment of the solid waste using stabilization/solidification technology;meanwhile we have a variety of outlooks on the future of the stabilization/solidification technology.

关键词：学位论文研究生青岛大学凝固工艺

Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 224-231页

作者： WU yuxuan XU Wenyuan yu Tianlai ji Yongcheng School of Civil Engineering Northeast Forestry UniversityHarbin 150040China

This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal *** mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics *** transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane *** results demonstrate that a 1%concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of *** phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component *** reduction in interaction slows the setting ***,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate.

关键词： polyurethane retarder setting time molecular dynamics diffusion coefficient

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大数据环境下的推荐系统

北京邮电大学学报 2015年第2期38卷 1-15页

作者：孟祥武纪威宇张玉洁北京邮电大学智能通信软件与多媒体北京市重点实验室北京100876

信息过载是大数据环境下最严重的问题之一,推荐系统作为有效缓解该问题的方法,受到工业界和学术界越来越多的关注.如何充分利用丰富的用户反馈、社会化网络等信息进一步提高推荐系统的性能和用户满意度,成为大数据环境下推荐系统的主要... 详细信息

信息过载是大数据环境下最严重的问题之一,推荐系统作为有效缓解该问题的方法,受到工业界和学术界越来越多的关注.如何充分利用丰富的用户反馈、社会化网络等信息进一步提高推荐系统的性能和用户满意度,成为大数据环境下推荐系统的主要任务.首先,对近几年大数据环境下的推荐系统进行了综述,对大数据和推荐系统进行了概述,对推荐系统在传统环境下和大数据环境下的区别进行了辨析;然后,根据层次化的框架对推荐系统关键技术、效用评价以及应用实践等进行了概括、比较和分析;最后,对大数据环境下推荐系统有待深入研究的难点和发展趋势进行了展望.

关键词：大数据推荐系统关键技术

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融合多种数据信息的餐馆推荐模型

软件学报 2019年第9期30卷 2869-2885页

作者：戴琳孟祥武张玉洁纪威宇智能通信软件与多媒体北京市重点实验室(北京邮电大学) 北京100876 北京邮电大学计算机学院北京100876

餐馆推荐可以利用用户的签到信息、时间上下文、地理上下文、餐馆属性信息以及用户的人口统计信息等挖掘用户的饮食偏好,为用户生成餐馆推荐列表.为了更加有效地融合这些数据信息,提出一种融合了多种数据信息的餐馆推荐模型,该模型首先... 详细信息

餐馆推荐可以利用用户的签到信息、时间上下文、地理上下文、餐馆属性信息以及用户的人口统计信息等挖掘用户的饮食偏好,为用户生成餐馆推荐列表.为了更加有效地融合这些数据信息,提出一种融合了多种数据信息的餐馆推荐模型,该模型首先利用签到信息和时间上下文构建“用户-餐馆-时间片”的三维张量,同时利用其他数据信息挖掘若干用户相似关系矩阵和餐馆相似关系矩阵;然后,在概率张量分解的基础上同时对这些关系矩阵进行分解,并利用 BPR 优化准则和梯度下降算法进行模型求解;最后得到预测张量,从而为目标用户在不同时间片生成相应的餐馆推荐列表.通过在两个真实数据集上的实验结果表明:相比于目前存在的餐馆推荐模型,所提出的模型有着更好的推荐效果和可接受的运行时间,并且缓解了数据稀疏性对推荐效果的影响.

关键词：餐馆推荐概率张量分解相似关系 BPR 优化梯度下降

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping yu Emily Choi Michael Qjiang Ling wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping CHENG jian wei Chao yuAN Bin yu Chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

恶性腹水源性腹腔间隔室综合征肝脏损伤的研究进展

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世界华人消化杂志 2017年第9期25卷 769-774页

作者：王宏业尉继伟大同大学附属医院肿瘤科山西省大同市037005

恶性腹水源性腹腔间隔室综合征(malignant ascites-induced abdominal compartment syndrome,MAACS)继发肝脏损伤,临床症状隐匿,受到的关注较少.探索MAACS继发肝脏损害具有重要的临床意义.近年来,随着临床对腹腔间隔室综合征的发病机制... 详细信息

恶性腹水源性腹腔间隔室综合征(malignant ascites-induced abdominal compartment syndrome,MAACS)继发肝脏损伤,临床症状隐匿,受到的关注较少.探索MAACS继发肝脏损害具有重要的临床意义.近年来,随着临床对腹腔间隔室综合征的发病机制及病理生理研究逐步深入,肝脏的继发改变成为研究的新热点.本文对MAACS继发肝脏损害中的病理生理过程、病理改变及治疗进行述评.

关键词：腹腔间隔室综合征恶性肿瘤腹水肝脏