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Nickel-catalyzed hydromonofluoromethylation of unactivated alkenes for expedient construction of primary alkyl fluorides

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Chinese Chemical Letters 2023年第3期34卷 279-282页

作者： Shan-Xiu Ni Yan-lin Li Hui-Qi Ni Yu-Xiang Bi jie Sheng Xi-Sheng Wang Department of Chemistry University of Science and Technology of ChinaHefei 230026China

A nickel-catalyzed direct hydromonofluoromethylation of unactivated olefins with industrial raw fluoroiodomethane is developed,furnishing various primary alkyl fluorides in a step-economic *** key factor to success is the use of pyridine-oxazoline as ligand and(MeO)_(2)MeSiH as the hydrogen *** transformation demonstrates high efficiency,mild conditions,good functional-group compatibility and great potential in the drug discovery.

关键词： Hydromonofluoromethylation Unactivated alkenes Nickel-catalysis Primary fluorides Ni-H species

Spatial Downscaling of Remote Sensing Precipitation Data in the Beijing-Tianjin-Hebei Region

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Spatial Downscaling of Remote Sensing Precipitation Data in ...

作者： Nuan Wang jie Yu lin Zhu Yanbing Wang Zhengyang He College of Resource Environment and Tourism Capital Normal University State Key Laboratory Incubation Base of Urban Environmental Processes and Digital Simulation Henan Geological Bureau China Chemical Geology and Mine Bureau Beijing Laboratory of Water Resources Security Beijing Municipal Education Commission Key Laboratory of 3-Dimensional Information Acquisition and Application Ministry of Education

Precipitation is an important part of the global hydrological cycle. The largescale, high-precision continuous precipitation data obtained by satellite remote sensing detection technology has become an important source of spatial precipitation data. However, because the spatial resolution of remote sensing precipitation data is still low, it is difficult to meet the needs of hydrological research, which restricts their application in drought and flood analysis, hydrological simulation, etc. In response to this problem, this paper takes the Beijing-Tianjin-Hebei region as the research area, downscaling the TRMM data and the GPM data space of the continuation plan, and increasing the spatial resolution of the data to 1 km. Compared with the original data, spatial downscaling data not only greatly improves the spatial resolution, but also increases the accuracy of the data, which has better applicability.

关键词： TRMM GPM Spatial Downscaling Geographically Weighted Regression

Low Altitude Small UAV Detection Based on YOLO model

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Low Altitude Small UAV Detection Based on YOLO model

第三十九届中国控制会议

作者： Xiyu Yuan jie Xia Jiang Wu JinXu Shi lin Deng School of Automation Science and Electrical Engineering Beihang University

Low altitude small UAV recently becomes a hot technology with rapid development and comprehensive application which raising many risks in Low-altitude airspace. Considering the characteristics of low altitude small UAV, previous approaches like radar and radio are insufficient, this paper is devoted to the detection of small UAV by using images from low-cost cameras. Method of detecting low altitude small UAV based on YOLO model with two neural networks, ResNet and DenseNet, is designed and performed. One small dataset is established accordingly. Experiment on the dataset shows that the detection method with YOLO model can make contributions to the low altitude UAV detection in complicated environments.

关键词： Low Attitude UAV Detection YOLO Neural Network

Synthesis and Properties of Mg-doped ZnO Nanobelts

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Semiconductor Photonics and Technology 2009年第4期15卷 225-228,251页

作者： LIU Hang ZHUANG Hui-zhao XUE Cheng-shan WANG jie LI Jun-lin Institute of Semiconductors Shandong Normal University Jinan 250014 CHN

The chemical vapor deposition(CVD)growth method is applicable to produce high-yield single-crystalline ZnO *** Mg-doped ZnO nanobelts with a smooth surface have been successfully *** morphology,microstructure and optical properties of the ZnO nanobelts were analyzed by X-ray diffraction(XRD),scanning electron microscope(SEM),transmission electron microscope(TEM),selective area electron diffraction(SAED),energy dispersive X-ray spectroscopy(EDS)and photoluminescence(PL)*** reveal that the ZnO nanobelts possess good crystalline *** special formation mechanism of crystal growth is discussed,emphasizing the effect of polar orientation on the nucleation and growth of the ZnO nanobelts.

关键词： Mg-doped ZnO nanobelts chemical vapour deposition method of crystal growth

An Electro-thermal Model and Its Application on SOE Estimation for LiFePO4/C Battery

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An Electro-thermal Model and Its Application on SOE Estimati...

作者： Luo ling Song Wenji lin Shili Lv jie Feng Ziping Guangzhou Institute of Energy Conversion Chinese Academy of Sciences University of Chinese Academy of Sciences

The state of energy(SOE)is an important state parameter and evaluation index to indicate the residual energy for LiFePO/C *** order to improve the estimation accuracy of SOE,the influence of the thermal energy inside the battery is researched by the electro-thermal energy model and an enhanced algorithm considering electrical energy and thermal energy is proposed to realize the accurate estimation of *** novel estimation model is verified by lots of experiments that it’s highly similar to the situation of actual energy consumption and has a high accuracy of SOE estimation.

关键词： Eletro-thermal model SOE LiFePO4/C battery

Low Power Consumption Thermo-optical Switch based on DR1/PMMA

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Low Power Consumption Thermo-optical Switch based on DR1/PMM...

全国第15次光纤通信暨第16届集成光学学术会议

作者： Zijian Cao Yunfei Yan jie Meng lin Jin Daming Zhang State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin University

In this paper,a low power consumption thermo-optical switch based on DRl/PMMA materials was *** material is easy to synthesis and has high cost-performance,high thermo-coefficient and the other advantages for electro-optical device. SiO was chosen as substrate material,DRl/PMMA as the core material and PMMA as the cladding *** SiO substrate can make the optical filed distribution near the heater,this structure is good for improve the modulation *** rectangle waveguide based Mach-Zehnder interferometer was chosen for this device.A coplanar waveguide electrode was chosen as figure 1. The coplanar waveguide heater ensured the high frequency response of *** the meanwhile, it is a heat sink can prevent the thermo power *** length of device is 3.5 cm and the length of heater is 1.5 *** test results show the power consumption is 30 mW and the extinction ratio is 19 dB.. The rise time and fall time are less than 0.5 *** work gives important information for design and fabrication of electro-optical and thermo-optical hybrid integrated devices.

关键词： DR1/PMMA Optical Switch Mach-Zehnder

胆囊癌根治性目的切除术达到教科书式结局对远期预后影响的全国多中心队列研究

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中华消化外科杂志 2024年第7期23卷 926-933页

作者：刘智鹏李子沐罗宇乐赵小林白洁江艳李云峰喻超黄帆吴兆平周进学尹大龙丁睿郭伟朱沂陈伟林科灿岳平程遥戴海粟张东陈志宇陆军军医大学第一附属医院肝胆外科全军肝胆外科研究所重庆400038 湖南省人民医院肝胆胰外科长沙410002 贵州医科大学附属医院肝胆外科贵阳550004 安徽医科大学第一附属医院普通外科合肥230022 九江市第一人民医院肝胆胰外科九江332001 郑州大学附属肿瘤医院肝胆胰外科郑州450003 中国科学技术大学附属第一医院肝胆外科合肥230002 空军军医大学第一附属医院肝胆胰外科西安710032 首都医科大学附属北京友谊医院普通外科北京100050 浙江大学医学院附属第二医院肝胆胰外科杭州310003 中山大学第一附属医院肝胆胰外科中山510080 福建医科大学孟超肝胆医院肝病中心福州350025 兰州大学第一医院普通外科兰州730013 重庆医科大学附属第二医院肝胆外科重庆400010 西安交通大学第一附属医院肝胆外科西安710061

目的探讨胆囊癌根治性目的切除术后达到肝脏外科中教科书式结局(TOLS)对远期预后的影响。方法采用回顾性队列研究方法。收集2014年1月至2021年1月中华消化外科菁英荟胆道外科学组全国多中心数据库15家医学中心收治的824例胆囊癌患者的... 详细信息

目的探讨胆囊癌根治性目的切除术后达到肝脏外科中教科书式结局(TOLS)对远期预后的影响。方法采用回顾性队列研究方法。收集2014年1月至2021年1月中华消化外科菁英荟胆道外科学组全国多中心数据库15家医学中心收治的824例胆囊癌患者的临床病理资料;男285例,女539例;年龄为(62±11)岁。根据TOLS评价标准,将患者分为达到TOLS和未达到TOLS。正态分布的计量资料以x±s表示,组间比较采用独立样本t检验;偏态分布的计量资料以M(Q1,Q3)表示,组间比较采用Mann‑Whitney U检验。计数资料以绝对数表示,组间比较采用χ^(2)检验。等级资料比较采用Mann‑Whitney U检验。采用Kaplan‑Meier法计算生存率和绘制生存曲线,Log‑rank检验进行生存分析。单因素分析和多因素分析采用COX逐步回归模型向后Wald法。结果(1)TOLS情况。824例行胆囊癌根治性目的切除术患者中,510例达到TOLS,314例未达到TOLS。(2)随访情况。824例行胆囊癌根治性目的切除术患者,排除出院后90 d内死亡的112例,712例患者纳入生存分析。510例达到TOLS患者的中位随访时间为22.1(11.4,30.1)个月,中位总生存时间为47.6(30.6,64.6)个月,5年总生存率为47.5%。202例未达到TOLS患者的中位随访时间为14.0(6.8,25.5)个月,中位总生存时间为24.3(20.0,28.6)个月,5年总生存率为21.0%。两者总生存情况比较,差异有统计学意义(χ^(2)=58.491,P<0.05)。(3)影响患者生存情况的因素分析。多因素分析结果显示:TOLS、癌胚抗原、CA19‑9、肿瘤分化程度为低分化、第八版美国癌症联合委员会(AJCC)T2期、第八版AJCC T3期和T4期、第八版AJCC N1期、第八版AJCC N2期、辅助治疗是胆囊癌根治性目的切除术后患者总生存时间的独立影响因素(风险比=0.452,1.479,1.373,1.612,1.455,1.481,1.835,1.978,0.538,95%可信区间为0.352~0.581,1.141~1.964,1.052~1.791,1.259~2.063,1.102~1.920,1.022~2.147,1.380~2.441,1.342~2.915,0.382~0.758,P<0.05)。结论达到TOLS的胆囊癌根治性目的切除术患者能够获得更好的远期预后。

关键词：胆道肿瘤肝切除教科书式结局影响因素分析预后

稳定表达Aβ特异性单链抗体的哺乳动物细胞株构建和功能研究

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中国生物工程杂志 2017年第2期37卷 1-7页

作者：温杰宋琳琳张莹王荷何金生洪涛北京交通大学理学院生命科学与生物工程研究院北京100044 中国疾病预防控制中心病毒病预防控制所北京100052

构建可以稳定表达Aβ特异性单链抗体(scFv)的哺乳动物细胞株。应用重叠延伸PCR的方法,以前期建立的Aβ特异性单克隆抗体(A8)的轻、重链可变区基因为模板,构建scFv的基因片段,通过(G_4S)_3或p2A两种不同的连接肽(linker)序列,拼接得到多... 详细信息

构建可以稳定表达Aβ特异性单链抗体(scFv)的哺乳动物细胞株。应用重叠延伸PCR的方法,以前期建立的Aβ特异性单克隆抗体(A8)的轻、重链可变区基因为模板,构建scFv的基因片段,通过(G_4S)_3或p2A两种不同的连接肽(linker)序列,拼接得到多种形式的scFv基因片段,用于构建真核表达载体。利用脂质体分别转染人宫颈癌细胞(Hela)和中国仓鼠卵巢细胞(CHO),Western blot鉴定scFv的表达情况;以潮霉素筛选获得稳定表达抗Aβ的scFv细胞株,以间接ELISA和斑点印迹分析所得scFv的抗原识别能力;采用体外细胞实验,在超微病理水平分析所得scFv的细胞保护作用。结果:成功构建了Aβ特异性scFv的3个真核表达载体pSecTag2/HygroA-VL-(G_4S)_3-VH、pSecTag2/HygroA-VH-(G_4S)_3-VL和pSecTag2/HygroA-VL-p2A-VH,获得了2株稳定表达Aβ特异性scFv的细胞株Hela-VL-p2A-VH和CHO-VL-(G_4S)_3-VH。Western blot结果表明了相应scFv的正确表达,间接ELISA和斑点印迹结果表明所分泌的细胞上清具有Aβ抗原识别能力,体外实验显示其具有阻断和抑制Aβ寡聚体细胞毒性的作用。稳定表达Aβ特异性单链抗体的细胞株有助于AD免疫治疗基础研究的进一步开展。

关键词：阿尔茨海默病 β淀粉样肽(Aβ) 单链抗体

冰冻单采血小板在外周血干细胞移植中的应用:与输注新鲜单采血小板效果比较

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中国组织工程研究与临床康复 2010年第27期14卷 5015-5017页

作者：杨孝顺谢琳朱鸿杰李琳华王桂华云南省委机关卫生所云南省昆明市650032 云南省肿瘤医院化疗中心云南省昆明市650118 解放军第五三三医院急诊科云南省昆明市650224 解放军昆明总医院成都军区血液中心云南省昆明市650032

背景：由于实行义务献血后血小板来源紧张,输注新鲜单采血小板有时难以保证。而冰冻单采血小板有较好的即刻止血效果,可用于各种低血小板患者的止血。目的：探讨冰冻单采血小板输注在外周血干细胞移植中的替代疗效。方法：44例血液病或... 详细信息

背景：由于实行义务献血后血小板来源紧张,输注新鲜单采血小板有时难以保证。而冰冻单采血小板有较好的即刻止血效果,可用于各种低血小板患者的止血。目的：探讨冰冻单采血小板输注在外周血干细胞移植中的替代疗效。方法：44例血液病或淋巴瘤患者均接受外周血干细胞移植,血小板计数低于40×109L-1,随机分为新鲜血小板组、冰冻血小板组,22例/组。外周血干细胞移植后0~14d,新鲜血小板组患者直接输注经专用白细胞滤器过滤后的新鲜单采血小板;冰冻血小板组患者将同型冰冻单采血小板取出后,放入37℃水浴迅速融化,用白细胞滤器过滤后,于40min内输注。一般每3d输注1次,10U/次,共输入3~16次,输入次数根据患者出血情况酌情增减。结果与结论：与新鲜血小板组比较,冰冻血小板组输注后24h血小板及凝血四项指标无明显变化（P〉0.05）;输注后48h血小板计数显著降低（P〈0.01）;输注后72h出血时间、凝血酶原时间、活化部分凝血活酶时间及血小板计数均显著降低（P〈0.05或P〈0.01）,凝血酶时间及纤维蛋白原无明显差异（P〉0.05）。建议在外周血干细胞移植中,应用冰冻单采血小板防止出血输注时间为2d输注1次。

关键词：血小板输注冰冻血小板外周血干细胞移植出血/止血干细胞