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倾斜摄影技术在京杭运河徐州段三维建模中的应用研究

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江苏水利 2024年第5期 41-44页

作者：徐良格尹萌薛振宁左曦徐州市水务局江苏徐州221000

结合京杭运河徐州段主河道及其支流开展的倾斜摄影与三维建模项目进行研究,提出了倾斜摄影与三维建模技术的优势与需求,并通过实际应用介绍了流域性河道开展倾斜摄影、三维建模与修饰的操作流程与关键步骤,为推进数字流域建设提供技术... 详细信息

结合京杭运河徐州段主河道及其支流开展的倾斜摄影与三维建模项目进行研究,提出了倾斜摄影与三维建模技术的优势与需求,并通过实际应用介绍了流域性河道开展倾斜摄影、三维建模与修饰的操作流程与关键步骤,为推进数字流域建设提供技术参考。

关键词：数字孪生数据底板倾斜摄影三维建模应用研究

3~5岁听障儿童与健听儿童不同送气方式塞音发音清晰度比较研究

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中国听力语言康复科学杂志 2024年第3期22卷 298-302页

作者：史泱尹梦雅曲春燕首都医科大学附属北京儿童医院北京100045

目的比较学龄前听障儿童与健听儿童塞音清晰度,分析不同送气方式下听障儿童不同发音部位塞音的发音难度,探讨影响其清晰度的原因,为送气塞音康复训练提供依据。方法选择3~5岁听障儿童104名和健听儿童36名,以《汉语构音能力测验词表》... 详细信息

目的比较学龄前听障儿童与健听儿童塞音清晰度,分析不同送气方式下听障儿童不同发音部位塞音的发音难度,探讨影响其清晰度的原因,为送气塞音康复训练提供依据。方法选择3~5岁听障儿童104名和健听儿童36名,以《汉语构音能力测验词表》为测试材料,分析不同送气方式塞音的发音清晰度。结果 (1)3~5岁健听儿童的塞音已习得(≥90%),各年龄段送气塞音的清晰度与不送气塞音相同,送气方式不同对各年龄段塞音清晰度的影响无显著差异(P>0.05);(2)3~5岁听障儿童的塞音均未习得(<90%),送气塞音的清晰度小于不送气塞音,两者的清晰度有显著差异(P=0.010≤0.01);(3)3~5岁各个年龄段无论送气与否,听障儿童与健听儿童的发音清晰度均有显著差异(P<0.05);(4)是否送气不影响听障儿童对舌根音声母的习得。结论听障儿童对发音位置靠前的送气塞音习得更加困难,训练时需加强听障儿童对送气的感知,提高送气塞音的清晰度。

关键词：听障儿童构音障碍塞音送气方式清晰度

银含量对快速热冲击下Sn−xAg−0.5Cu焊点显微组织和力学性能的影响

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Transactions of Nonferrous Metals Society of China 2024年第6期34卷 1922-1935页

作者：彭晨王善林吴鸣尹立孟陈玉华叶科江陈维政张体明谢吉林南昌航空大学江西省航空构件成形与连接重点实验室南昌330036 江西省智能产业技术创新研究院南昌330200 重庆科技学院冶金与材料工程学院重庆401331

使用高频感应加热设备研究Ag含量对快速热冲击下Sn−xAg−0.5Cu焊点的显微组织和剪切强度的影响。结果表明,Ag含量的增加使焊点表面更致密光滑,减少焊点内部长条状Cu6Sn5金属间化合物(IMC)的产生,从而提高焊点的抗氧化性。Ag能够加快焊点... 详细信息

使用高频感应加热设备研究Ag含量对快速热冲击下Sn−xAg−0.5Cu焊点的显微组织和剪切强度的影响。结果表明,Ag含量的增加使焊点表面更致密光滑,减少焊点内部长条状Cu6Sn5金属间化合物(IMC)的产生,从而提高焊点的抗氧化性。Ag能够加快焊点界面IMC层的生长速度,Cu6Sn5层的生长速度由体扩散和晶界扩散共同决定,Cu3Sn层的生长速度由体扩散和界面反应共同决定。在快速热冲击环境下,焊点的断裂模式从韧性断裂转变为脆性断裂,而高Ag含量使得焊点的断裂模式转变时间更短,降低焊点的抗热疲劳性能。

关键词： Ag含量快速热冲击 Sn−Ag−Cu 焊点生长动力学断裂模式

Ethylene/1-Hexene Copolymerization with Modified Ziegler-Natta Catalyst

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Chemical Research in Chinese Universities 2019年第6期35卷 1089-1094页

作者： yin meng ZHANG Zhiqiang XIONG Yujie LIU Min ZHANG Yan MI Puke Key Laboratory for Ultrafine Materials Ministry of EducationShanghai Key Laboratory of Advanced Polymeric MaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237P.R.China

Siloxane compounds were treated with the compounds containing internal donors,such as aromatic ester,phosphate,or 1,3-diether compounds,and the resulting intermediates were further reacted with TiCl4 to form the modified Ziegler-Natta catalysts for ethylene/1-hexene(E-H)*** the modified Ziegler-Natta catalysts,the effect of the internal donors and the molar ratio of alcohol to magnesium on the catalyst performance was investigated by the orthogonal *** synthetic method of the catalysts was also optimized by choosing the proper way to mix the internal *** branch degree,sequence structure,molecular weight,and molecular weight distribution of the copolymer products were determined by Fourier transform infrared spectroscopy(FTIR),carbon-13 nuclear magnetic resonance(^13C NMR)spectrometry and gel permeation chromatography(GPC).Under the optimum conditions,the catalytic system with tetraethyl orthosilicate and 2,2-dimethoxypropane as the internal donors exhibited the best performance with an activity of 926.74 g copolymer/(g Cat·h^?1).The branch degree,1-hexene content,and molecular weight distribution of the resulting copolymers reached up to 40 branches/1000C,5.99%and 5.8,respectively.

关键词： Ziegler-Natta catalyst Internal donor Lewis base Ethylene-olefin copolymerization Copolymer structure

Recent Progress in Networked Control Systems——A Survey

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International Journal of Automation and computing 2015年第4期12卷 343-367页

作者： Yuan-Qing Xia Yu-Long Gao Li-Ping Yan meng-yin Fu School of Automation Beijing Institute of Technology

For the past decades,networked control systems(NCSs),as an interdisciplinary subject,have been one of the main research highlights and many fruitful results from different aspects have been *** these growing research trends,it is significant to consolidate the latest knowledge and information to keep up with the research *** this paper,the results of different aspects of NCSs,such as quantization,estimation,fault detection and networked predictive control,are *** addition,with the development of cloud technique,cloud control systems are proposed for the further development of NCSs.

关键词： Networked control systems quantization filter data fusion fault detection networked predictive control cloud control systems.

A functional PVA aerogel-based membrane obtaining sutureability through modified electrospinning technology and achieving promising anti-adhesion effect after cardiac surgery

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Bioactive Materials 2022年第4期7卷 355-366页

作者： Dawei Jin Shuofei Yang Shuting Wu meng yin Haizhu Kuang Department of Cardiothoracic Surgery Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dong Fang RoadShanghai200127People’s Republic of China Department of Vascular Surgery Renji HospitalSchool of MedicineShanghai Jiao Tong University160 Pujian RoadShanghai200127People’s Republic of China Department of Pharmacy The Third Affiliated Hospital(The Affiliated Luohu Hospital)of Shenzhen UniversityShenzhen518001Guangdong ProvincePeople’s Republic of China

Pericardial barrier destruction,inflammatory cell infiltration,and fibrous tissue hyperplasia,trigger adhesions after cardiac *** are few anti-adhesion materials that are both functional and sutureable for pericardial ***,a few studies have reported on the mechanism of preventing pericardial ***,a functional barrier membrane with sutureability was developed via a modified electrospinning *** was composed of poly(L-lactide-co-caprolactone)(PLCL)nanofibers,poly(vinyl alcohol)(PVA)aerogel,and melatonin,named *** PPMT had a special microstructure manifested as a staggered arrangement of nanofibers on the surface and a layered macroporous aerogel structure in a *** providing the porosity and hydrophilicity obtained from PVA,the structure also had suitable mechanical properties for stitching due to the addition of PLCL ***,it inhibited the proliferation of fibroblasts by suppressing the activation of Fas and P53,and achieved anti-inflammatory effects by affecting the activity of inflammatory cells and reducing the release of pro-inflammatory factors,such as interleukin 8(IL-8)and tumor necrosis factorα(TNF-α).Finally,in vivo transplantation showed that it up-regulated the expression of matrix metalloproteinase-1(MMP1)and tissue inhibitor of metalloproteinase-1(TIMP1),and down-regulated the expression of Vinculin and transforming growth factorβ(TGF-β)in the myocardium,thereby reducing the formation of ***,these results demonstrate a great potential of PPMT membrane for practical application to anti-adhesion.

关键词： Anti-Adhesion PVA aerogel-Based membrane Sutureability Modified electrospinning technology Pericardial reconstruction

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羧基化改性海带渣对结晶紫的吸附性能研究

粮食与油脂 2024年第5期37卷 84-90页

作者：杜国丰陈小焕梁飞龙尹梦琪杨杰书梁海营口理工学院化学与环境工程学院辽宁营口115014

采用丁二酸酐(SA)对海带渣(LJR)进行羧基化修饰。利用红外光谱、扫描电镜、能量色散光谱对LJR和改性海带渣(CLJR)进行表征,对比改性前后LJR对结晶紫(CV)的吸附性能,并确定CLJR的最优吸附条件。结果发现:CLJR在1728 cm^(-1)处出现羧基的... 详细信息

采用丁二酸酐(SA)对海带渣(LJR)进行羧基化修饰。利用红外光谱、扫描电镜、能量色散光谱对LJR和改性海带渣(CLJR)进行表征,对比改性前后LJR对结晶紫(CV)的吸附性能,并确定CLJR的最优吸附条件。结果发现:CLJR在1728 cm^(-1)处出现羧基的特征峰,孔隙结构明显增多,羧基化改性增强了LJR对CV的吸附性能。CLJR的最优吸附条件为初始质量浓度100 mg/L、吸附剂投加量0.8 g/L、初始pH 5~11;升高温度对LJR和CLJR的吸附过程有利。

关键词：海带渣羧基化改性吸附结晶紫吸附等温线

A New Method of Deoxygenation in the Synthesis of Taxanes by Hypophosphorous Acid

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有机化学 2003年第Z1期23卷 340-341页

作者： GU Jun ZHANG meng yin Da-Li Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050

　　Based on the chemistry involved in the radical chain deoxygenation of alcohols by the Barton-McCombie reaction, numerous applications in the synthesis of taxanes were reported. [1] In the original Barton-McCombie method,tributyltin hydride was the hydrogen atom source and tributyltin radical generated from the hydride served as a chain carrier. [2] Although the method gave the good yield and found many applications, the problems associated with the price, toxicity and removal of tin residues prompted search for other hydrogen atom sources. Radical chain deoxygenation of alcohols can be carried out with phosphorus centered radicals, generated from hypophosphorous acid orits salts. [3]……

关键词： Hypophosphorous Acid hydrogen atom hypophosphorous acid

Meta-analysis of outcomes from drug-eluting stent implantation in infrapopliteal arteries

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World Journal of Clinical Cases 2023年第22期11卷 5273-5287页

作者： Ming-Xuan Li Hai-Xia Tu meng-Chen yin Department of Vascular Surgery Beijing Fengtai You'anmen HospitalBeijing 100069China

BACKGROUND Percutaneous drug-eluting stent implantation(DESI)is an emerging and promising treatment modality for infrapopliteal artery diseases(IPADs).This systematic review and meta-analysis summarizes and quantitatively analyzes the outcomes of DESI in IPADs considering the hazard ratio(HR),which is a more accurate and appropriate outcome measure than the more commonly used relative risk and odds *** To explore the superiority of drug-eluting stents(DESs)vs traditional treatment modalities for *** The following postoperative indicators were the outcomes of interest:All-cause death(ACD)-free survival,major amputation(MA)-free survival,target lesion revascularization(TLR)-free survival,adverse event(AE)-free survival,and primary patency(PP)*** outcome measures were then compared according to their respective HRs with 95%confidence intervals(CIs).The participants were human IPAD patients who underwent treatments for infrapopliteal *** was set as the intervention arm,and traditional percutaneous transluminal angioplasty(PTA)with or without bare metal stent implantation(BMSI)was set as the control arm.A systematic search in the Excerpta Medica Database(Embase),PubMed,Web of Science,and Cochrane Library was performed on November 29,*** controlled studies published in English with sufficient data on outcomes of interest for extraction or conversion were *** studies did not directly report the HRs but gave a corresponding survival curve,we utilized Engauge Digitizer software and standard formulas to convert the information and derive ***,meta-analyses were conducted using a random-effects *** Five randomized controlled trials and three cohort studies involving 2639 participants were *** ACDfree and MA-free survival HR values for DESI were not statistically significant from those of the control treatment(P>0.05);however,the HR values for TLR-free,AE-free,and PP-survival differed significantly[2.65(95%

关键词： Infrapopliteal Drug-eluting stent Below-the-knee Meta-analysis Hazard ratio