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Performance analysis of WCDMA wireless access standard

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Frontiers of Electrical and Electronic Engineering in China 2007年第1期2卷 57-62页

作者： FU Haiyang SHEN hui lu Suhua College of Communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

Based on the transmitting power of a mobile station and the maximum cell capacity,the analysis of a wide-band code-division multiple access(WCDMA)standard and the comparison of the corresponding parameters with CDMA2000 or evolution-data only(EV-DO)are given in this *** result proves that the mobile station of WCDMA cannot provide the required transmitting power on the specified frequency band and data rate,and the symmetrical capacity in an up-downlink cannot meet the requirement of a mobile *** is questionable for the International Telecommunication Union(ITU)to select the frequency band of 2 GHz for vehicular mobile telecommunication and unreasonable to distribute it over the downlink and uplink channels *** CDMA20001X EV-DO or enhanced data rate for GSM evolution(EDGE),which adopts the Time Division Multiple Access(TDMA)mode,can provide the high-speed data rate for a wireless access.

关键词： WCDMA electromagnetic radiation transmit power cell capacity data rate

Facile Synthesis of Polycarbonate Diol via Copolymerization of CO_(2) and Cyclohexene Oxide Catalysed by a Combination of One-Component Phosphonium Borane Lewis Pair and Water

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Chinese Journal of Polymer Science 2023年第5期41卷 735-744,I0009页

作者： xiao-Wu Wang Ji-Wen hui Yu-Tao Li Yan-Ru Gu Zhi-Bo Li State Key Laboratory Base of Eco-Chemical Engineering/College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China Key Laboratory of Biobased Polymer Materials Shandong Provincial Education Department/School of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China

Well-defined polycarbonate diol was successfully synthesized through a strategy using a combination of organocatalyst and *** strategy was less developed in organocatalyzed polymerization and frequently regarded as side ***,one-component phosphonium borane Lewis pairs PB1-PB8 were successfully applied in the copolymerization of CO_(2) and cyclohexene oxide(CHO)to generate poly(CHO-alt-CO_(2))carbonate(PCHC).Parameters of linker length and counter anion effects on the catalyst activity were *** was found that Lewis pair PB3 served as a dual initiator and catalyst in the copolymerization of CHO and CO_(2) with or without the presence of *** contrast,Lewis pair PB8 can serve as a true catalyst for the preparation of well-definedα,ω-hydroxyl PCHC *** was achieved by introducing a labile CF3COO group as counter anion through anion exchange reaction while water molecules acted as chain transfer *** function of trifluoroacetate group in the polymerization process was investigated in detail and possible mechanism was *** changing the amount of water and catalyst loading,PCHC diols with varied molecular weight(1.5 kg/mol to 7.5 kg/mol),low dispersities(D99%)could be easily *** low molecular weight PCHC diol was used as a bifunctional macroinitiator for the ring-opening polymerization of L-lactide(LLA)to afford ABA triblock copolymer in one-pot synthesis.

关键词： Polycarbonate Phosphonium borane Lewis pair CO_(2)utilization Organocatalysis Ring-opening polymerization

基于DRG的新疆三级综合医院医疗服务绩效评价

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中华医院管理杂志 2024年第2期40卷 119-124页

作者：尚慧恩刘艳丽乔心雨张艳敏方金鸣路阳新疆医科大学公共卫生学院乌鲁木齐830001 新疆维吾尔自治区医疗卫生服务管理指导中心乌鲁木齐830001 新疆维吾尔自治区人民医院科研教育中心乌鲁木齐830001 武汉市第四医院质量管理办公室武汉430033

目的基于疾病诊断相关分组(DRG)综合评价新疆三级综合医院的医疗服务绩效水平, 为各级卫生行政部门提供决策参考。方法自新疆医院质量与绩效评价平台提取2022年三级综合医院的病案首页信息, 参照《自治区级医疗机构综合绩效考核与评价... 详细信息

目的基于疾病诊断相关分组(DRG)综合评价新疆三级综合医院的医疗服务绩效水平, 为各级卫生行政部门提供决策参考。方法自新疆医院质量与绩效评价平台提取2022年三级综合医院的病案首页信息, 参照《自治区级医疗机构综合绩效考核与评价实施方案(1.1版)》中三级综合医院的医疗服务绩效评价指标体系确定本研究的评价指标, 并邀请专家确定指标权重。采用加权TOPSIS法对新疆28家三级综合医院的DRG医疗服务绩效进行评价。结果共纳入28家医院的1 045 458例病案首页数据。选取医院业务能力、医疗服务水平、医疗服务效率、外科能力、重点专科能力和医疗安全6个一级指标和9个二级指标, 二级指标中权重排名前3的分别为病例组合指数(20%), 三、四级手术占比(15%)和重点监控病种占比(15%)。加权TOPSIS法评价排名前3的医院是A4、A6和B11, Ci值分别为0.914、0.811和0.591, 其他25家医院的Ci值均<0.5, 而且Ci值最低的B5医院仅为0.070。结论新疆三级综合医院的医疗服务绩效水平整体不高且差异较大。建议通过加大援疆帮扶力度, 推进各类医疗联合体建设与远程医疗协作, 促进优质医疗资源扩容和区域医疗协同发展, 同时应强化三级医院功能定位, 完善绩效管理机制, 并结合医院实际采取针对性的措施持续提升医疗服务绩效水平。

关键词：疾病诊断相关分组加权TOPSIS法三级综合医院医疗服务绩效评价新疆维吾尔自治区

Effects of PbO poisoning on Ce-Mn/AC catalyst for low-temperature selective catalytic reduction of NO with NH_(3)

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Journal of Iron and Steel Research International 2021年第2期28卷 133-139页

作者： Zeng-hui Su Shan Ren Tian-shi Zhang Jie Yang Yu-han Zhou lu Yao College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

As a common heavy metal in the sintering flue gas,Pb can exist in the form of oxide(PbO)and lead to the decrease in the denitration catalysts ***-Mn/AC(activated carbon)and PbO-Ce-Mn/AC catalysts were prepared by impregnation method and their selective catalytic reduction of NH_(3) with NO was *** showed that selective catalytic reduction activity of Ce-Mn/AC decreased remarkably after doping *** the NO conversion of Ce-Mn/AC reached 94.52% at 200℃,while the value was reduced to 65.8% after doping PbO at the same *** doping of PbO decreased the total pore volume and oxygen functional groups of activated carbon,increased crystallinity of Mn oxides on the catalyst,decreased Mn^(4+) and chemisorbed oxygen content and then inhibited the“fast selective catalytic reduction”denitration reaction for Ce-Mn/AC *** this basis,the poisoning effects of lead oxide on Ce-Mn/AC catalysts for low-temperature selective catalytic reduction were revealed.

关键词： Ce-Mn/AC catalyst PbO poisoning Fast selective catalytic reduction Poisoning effect

The design, manufacture and application of multistable mechanical metamaterials-a state-of-the-art review

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International Journal of Extreme Manufacturing 2023年第4期5卷 416-452页

作者： Rui Xu Chuanqing Chen Jiapeng Sun Yulong He Xin Li Ming-hui lu Yanfeng Chen College of Engineering and Applied Sciences Nanjing UniversityNanjingJiangsu 210093People’s Republic of China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094People’s Republic of China Institute of Applied Mechanics College of Mechanical and Vehicle EngineeringTaiyuan University of TechnologyTaiyuan 030024People’s Republic of China

Multistable mechanical metamaterials are a type of mechanical metamaterials with special features,such as reusability,energy storage and absorption capabilities,rapid deformation,and amplified output *** metamaterials are usually realized by series and/or parallel of bistable *** can exhibit multiple stable configurations under external loads and can be switched reversely among each other,thereby realizing the reusability of mechanical metamaterials and offering broad engineering *** paper reviews the latest research progress in the design strategy,manufacture and application of multistable mechanical *** divide bistable structures into three categories based on their basic element types and provide the criterion of their *** manufacturing techniques to fabricate these multistable mechanical metamaterials are introduced,including mold casting,cutting,folding and three-dimensional/4D ***,the prospects of multistable mechanical metamaterials for applications in soft driving,mechanical computing,energy absorption and wave controlling are ***,this paper highlights possible challenges and opportunities for future *** review aims to provide insights into the research and development of multistable mechanical metamaterials.

关键词： multistable mechanical metamaterials bistable units mechanical properties design and manufacture

Research of Modeling and Simulation on Adaptive Front-Lighting System for Corner Based on CCD 25th

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Research of Modeling and Simulation on Adaptive Front-Lighti...

蒸烫预处理对铁棍山药片干燥及品质变化的影响

第25届中国控制与决策会议

作者： Fengqun Guo hui xiao Shouzhi Tang College of Electronic and Information Engineering Tongji University

ISBN: (纸本)9781467355339

This paper analyzed photometric characteristics of vehicle headlamps when turning the corner, and developed a new kind of AFS （adaptive front-lighting system） based on CCD （charge-coupled device） which was better than traditional AFS. This new AFS used CCD image sensor to detect information about the corner and then sent curvature radius to electronic control units in advance. Meanwhile, electronic control units would calculate accurate rotation angle of headlamps through velocity and curvature radius, and send it to motor to adjust headlamps to get the lighting beam which was suitable for the corner. Through this way, it could avoid "blind spot" caused by the fixed lighting area when coming into the corner, and improve driving safety. This paper gave a modeling for horizontal rotation angle of vehicle headlamps, and simulated it with MATLAB.

关键词： photometric characteristics adaptive front-lighting system charge-coupled device curvature radius horizontal rotation angle modeling and simulation

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食品科技 2024年第2期49卷 24-31页

作者：谢永康李萍李星仪杨慧郑志安路风银河南省农业科学院农副产品加工研究中心河南郑州450002 中国农业大学工学院北京100083

以铁棍山药片为试材,采用不同的烫漂时间对铁棍山药片进行烫漂预处理,测定了干燥前后铁棍山药片色泽、质构、多酚氧化酶(Polyphenol oxidase,PPO)和过氧化物酶(Peroxidase,POD)的活性,并观察了水分迁移规律及微观结构,以期获得铁棍山药... 详细信息

以铁棍山药片为试材,采用不同的烫漂时间对铁棍山药片进行烫漂预处理,测定了干燥前后铁棍山药片色泽、质构、多酚氧化酶(Polyphenol oxidase,PPO)和过氧化物酶(Peroxidase,POD)的活性,并观察了水分迁移规律及微观结构,以期获得铁棍山药最佳的预处理工艺。结果表明:蒸烫预处理增加了山药片干燥时间,降低了干燥速率;烫漂60 s和90 s时,山药片总色差值较低;烫漂干燥后的山药片硬度值、弹性值、黏性值随着烫漂时间增加而增加,烫漂时间0~60 s时,其值均显著低于鲜样(P<0.05),烫漂90 s和120 s时显著增大;烫漂90 s后,山药片中的POD已完全失活;烫漂后山药片内部水分在60 s至120 s区间显著增加(P<0.05);从微观结构分析,烫漂超过90 s时,过度烫漂导致细胞组织严重破坏。综合分析,铁棍山药片蒸烫预处理的最佳时间在60~90 s,该研究可为探究山药片蒸汽烫漂的品质调控提供理论参考依据。

关键词：烫漂山药片干燥特性理化性质

Identification of a delayed leaf greening gene from a mutation of pummelo

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Science China(Life Sciences) 2021年第7期64卷 1165-1173页

作者： hui-Wen Yu Zhi-Hao lu Xia Wang Dan Liu Jia-Xian He xiao-Lin Jiang Ling-Jun Ke Wen-Wu Guo Xiu-Xin Deng Qiang Xu Key Laboratory of Horticultural Plant Biology(Ministry of Education) Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Landscape Plants with Fujian and Taiwan Characteristics ofFujian Colleges and Universities Minnan Normal UniversityZhangzhou 363000China

Delayed greening of young leaves is an unusual phenomenon of plants in *** are mostly evergreen tree ***,a natural mutant of“Guanxi”pummelo(Citrus maxima),which shows yellow leaves at the young stage,was characterized to identify the genes underlying the trait of delayed leaf greening in plants.A segregating population with this mutant as the seed parent and a normal genotype as the pollen parent was *** DNA pools respectively from the leaves of segregating seedlings with extreme phenotypes of normal leaf greening and delayed leaf greening were collected for *** segregant analysis(BSA)and In Del marker analysis demonstrated that the delayed leaf greening trait is governed by a 0.3 Mb candidate region on chromosome *** expression analysis further identified a key candidate gene(Citrus Delayed Greening gene 1,CDG1)in the 0.3 Mb region,which showed significantly differential expression between the genotypes with delayed and normal leaf greening *** was a 67 bp In Del region difference in the CDG1 promoter and the In Del region contains a TATA-box *** laser-scanning microscopy revealed that the CDG1-GFP fusion protein signals were co-localized with the chloroplast signals in the *** of CDG1 in tobacco and Arabidopsis led to the phenotype of delayed leaf *** results suggest that the CDG1 gene is involved in controlling the delayed leaf greening phenotype with important functions in chloroplast development.

关键词： citrus pummelo delayed leaf greening chlorophyll

基于CiteSpace的蜂蜜安全性研究现状与热点分析

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食品工业科技 2024年第13期45卷 389-401页

作者：肖甜王燕杨帆许华灯钟晓红唐其陆英金秀娥王峻郑亚杰湖南农业大学国家植物功能成分利用工程技术研究中心湖南长沙410128 湖南农业大学园艺学院湖南长沙410128 湖南省土壤肥料工作站湖南长沙410006 湖南省岳阳县原种场湖南岳阳414000 湖北省兽药监察所湖北武汉430000

为了梳理蜂蜜安全性研究的现状及热点,本文基于中国知网(CNKI)数据库和Web of Science(WOS)核心数据库,运用CiteSpace软件对发文趋势、发表期刊、作者、机构、国家(地区)、关键词等内容进行分析及可视化展示。从上述数据库中得到169篇... 详细信息

为了梳理蜂蜜安全性研究的现状及热点,本文基于中国知网(CNKI)数据库和Web of Science(WOS)核心数据库,运用CiteSpace软件对发文趋势、发表期刊、作者、机构、国家(地区)、关键词等内容进行分析及可视化展示。从上述数据库中得到169篇中文文献和281篇英文文献。分析表明蜂蜜安全性研究方向中文文献的发文量自2011年起呈上升趋势,英文文献发文量自2007年起呈现出波动性上升趋势,近十五年来英文文献的发文量多于中文文献;张强和Gunduz A分别是发表中文和英文文献量最多的作者,中英文研究领域的学者之间有相对固定的研究合作关系,但各个团体之间的合作程度较低;《蜜蜂杂志》和《Food Chemistry》分别是发表蜂蜜安全性文献最多的中英文期刊,中英文发文期刊都以食品领域为主;云南省疾病预防控制中心和Karadeniz Technical University分别是发表中文和英文文献量最多的研究机构,国内研究机构间的合作较少;研究国家(地区)中土耳其是影响力最大的国家,其次是中国、波兰和新西兰;中文文献在研究初期以“肉毒杆菌”“粉源植物”“雷公藤”“蜂蜜中毒”等为研究热点;2000年之后,色谱、光谱、扫描电镜等技术日渐成熟,“蜂蜜孢粉学”“气相色谱”等关键词出现,气相色谱、液相色谱、液质联用、扫描电镜等检测手段成为蜂蜜安全性研究中的热门研究方法。英文文献在研究初期以“pyrrolizidine alkaloids”“mad honey”“grayanotoxin”“natural toxicants”等为研究热点,说明此阶段主要是研究毒蜂蜜以及吡咯里西啶生物碱、梫木毒素等蜂蜜中检测到的天然毒素;随着色谱等技术的发展,“mass spectrometry”等关键词开始出现。可以看出,中英文文献研究在热点领域基本一致,都是以有毒蜜、蜂蜜中毒、蜂蜜中毒性成分检测和溯源等为主;但在侧重点上略有不同,国内有毒蜜源植物以雷公藤、钩吻、博落回等为主,蜂蜜中毒性成分检测以雷公藤甲素、钩吻素子等成分为主,国外蜂蜜中毒事件多是因为梫木毒素、吡咯西啶生物碱或羟基马桑毒素等造成。本研究为分析蜂蜜安全性的研究内容和发展历程及判断研究热点提供参考。

关键词：蜂蜜安全性文献计量学 CiteSpace 现状与热点

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