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Science China Chemistry 2010年第3期53卷 568-574页

作者： Chen, Yi Chang Liu, Xian Xian Huang, Hong wu, wei wei Zheng, Yan Song Department of Chemistry Huazhong University of Science and Technology Wuhan 430074 China Department of Chemistry Guilin Normal College Guilin 541001 China

t-Butyl and t-pentylcalix[4]arenes bearing two 2-naphthol-1-hydrazone groups at the lower rim were synthesized,and showed excited-state intermolecular proton transfer fluorescent signal with basic *** are more sensitive to dihydrogen phosphate anion than to fluoride anion,although the latter has stronger *** with t-butylcalix[4]arene bearing two 2-naphthol-1-hydrazone groups,t-pentylcalix[4]arenes derivative has a larger fluorescent difference between dihydrogen phosphate and fluoride *** finding may be used to analyze dihydrogen phosphate anion in the presence of fluoride anion and provide a new approach for designing fluorescence probes that are highly selective for H2PO4-.

关键词： calixarene probe for anions fluorescence dihydrogen phosphate anion excited-state proton transfer

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基于真实解剖模型的肺肿瘤微波消融研究

医疗卫生装备 2024年第9期45卷 27-34页

作者：刘菊高宏建王琦张宇博何慧静吴薇薇吴水才北京工业大学化学与生命科学学院北京100124 首都医科大学生物医学工程学院北京100069

目的:基于真实解剖模型研究肺肿瘤的微波消融(microwave ablation,MWA)结果,以更有效地规划微波天线的穿刺方向,实现个性化术前仿真。方法:首先,基于真实患者的肺部CT数据构建由肺组织、肿瘤和血管系统等组成的个性化MWA仿真模型。其次... 详细信息

目的:基于真实解剖模型研究肺肿瘤的微波消融(microwave ablation,MWA)结果,以更有效地规划微波天线的穿刺方向,实现个性化术前仿真。方法:首先,基于真实患者的肺部CT数据构建由肺组织、肿瘤和血管系统等组成的个性化MWA仿真模型。其次,通过对电磁场和生物传热场2个物理场进行耦合求解来仿真MWA效果,得到消融热凝固区的大小和肺组织的温度分布。最后,从电导率和血液灌注2个维度定量评估血管网络对消融结果的影响,并分析大血管与天线处于不同距离(大血管与天线尖端相距5和10 mm)和穿刺方向下(大血管相对于天线尖端平行和相交)的消融结果。结果:血管网络的存在使热凝固区体积减小0.5%~3.7%,且血液灌注使得消融温度大幅下降、热凝固区体积大幅减小。随着大血管与天线之间的距离增加,大血管所带来的降温效果逐渐减小。在相同的治疗参数下,大血管与天线处于平行方向形成的热凝固区明显大于相交方向形成的热凝固区。结论:基于真实CT数据的个性化MWA仿真分析可获得更接近实际情况的温度分布和损伤估算,从而为MWA精准治疗肺肿瘤以及协助医生确定微波天线的穿刺方向提供重要的参考和指导。

关键词：肿瘤治疗肺肿瘤微波消融真实解剖模型仿真分析

多中心四肢创伤性骨髓炎的临床特征分析及预后研究

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中国骨与关节杂志 2024年第3期13卷 184-189页

作者：张茹琦张乐刘泽民李超邬惟为张永红山西医科大学公共卫生学院流行病学教研室太原030001

目的多中心分析山西地区四肢创伤性骨髓炎患者的临床特征及预后因素。方法查阅山西医科大学第二医院、省人民医院、白求恩医院、运城市中心医院4家医院电子病历系统,回顾分析2016年1月1日至2021年12月31日确诊为四肢创伤性骨髓炎患者... 详细信息

目的多中心分析山西地区四肢创伤性骨髓炎患者的临床特征及预后因素。方法查阅山西医科大学第二医院、省人民医院、白求恩医院、运城市中心医院4家医院电子病历系统,回顾分析2016年1月1日至2021年12月31日确诊为四肢创伤性骨髓炎患者的基本信息、实验室指标、病原菌培养结果,根据出院情况分为预后良好组和预后不良组,组间比较用χ^(2)或Mann-Whitney U检验,多元Logistic回归模型分析预后因素。结果 374例四肢创伤性骨髓炎男女比例为3.2∶1,中位发病年龄为47 (33,58)岁;以开放性骨折[241例(64.4%)]多见,致伤原因常见于交通伤[150例(40.1%)];胫骨[201例(53.7%)]为感染好发部位;血清炎症标志物阳性率为白细胞18.7%、C反应蛋白(C-reactive protein,CRP) 62.1%、红细胞沉降率75.0%;病原菌培养阳性率为69.8%,单一致病菌145例(73.2%),以金黄色葡萄球菌[73例(50.3%)]最常见。多元Logistic回归显示CRP (OR=0.965,95%CI:0.924~0.989)是四肢创伤性骨髓炎的预后因素。结论四肢创伤性骨髓炎多见于男性,继发于开放性骨折,好发于胫骨,金黄色葡萄球菌为常见致病菌;CPR是四肢创伤性骨髓炎的预后因素。

关键词：骨髓炎骨折,开放性金黄色葡萄球菌并发症

Development of component stiffness equations for thread-fixed one-side bolt connections to an enclosed rectangular hollow section column under tension

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： Fu-wei wu Yuan-Qi LI Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Blind Signal Reception in Downlink Generalized Spatial Modulation Multiuser MIMO System Based on Minimum Output Energy

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Chinese Journal of Electronics 2024年第2期33卷 504-515页

作者： wei-Chiang wu College of Mechanical and Electrical Engineering Sanming University

This paper considers downlink multiuser multiple-input-multiple-output system with parallel spatial modulation scheme, in which base station transmitter antennas are separated into K groups corresponding to K user terminals. Generalized spatial modulation is employed, in which a subset(more than single antenna) of transmit antenna array are activated and the activating pattern corresponds to specific spatial symbol. Different from existing precoding-based algorithms, we develop a two-stage detection scheme at each user terminal: In the pre-processing stage, a minimax algorithm is proposed to identify the indices of active antennas, where the key idea is that the minimum output energy of the detector is maximized; A constrained minimum output energy algorithm is proposed in the post-processing stage to mitigate multiuser interference and extract temporal symbols. Compared with existing precoding-based algorithms, the complexity is significantly reduced. Moreover, the proposed algorithm is semi-blind,in which only a small subset of channel state information is required to identify active antennas as well as eliminate multiuser interference. Simulation results demonstrate that the proposed algorithm is near-far resistant and the spectral efficiency is extensively increased compared to the conventional spatial modulation scheme.

关键词： GSM Spectral efficiency Computer network reliability Transmitting antennas Modulation Symbols Downlink

Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient

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Chinese Journal of Chemical Engineering 2024年第5期69卷 212-219页

作者： Guangxia Jin Yuxue wu Feng wei School of Biological and Chemical Engineering NingboTech UniversityNingbo 315100China

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar *** study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive *** introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream ***,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation ***,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for *** using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

关键词： Solvent gradient Twin-column recycling chromatography Purification Minor component Natural products

Almost Periodic Type Group Actions on Compact Quantum Metric Spaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 568-594页

作者： Bo Tao LONG wei wu College of Mathematics MIIT Key Laboratory of Mathematical Modelling and High Performance Computing of Air VehiclesNanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China School of Mathematical Sciences Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal UniversityShanghai 200241P.R.China

A compact quantum metric space is a complete order unit space A endowed with a Lipnorm *** give some characterizations of almost periodic type group actions on a compact quantum metric space(A,L)by means of several kinds of subsets of A,its induced equicontinuous actions on several important subsets of the dual Banach space A*,and the Lip-norm L with its induced metric space structures on the state space S(A)of A.

关键词： Lip-norm compact quantum metric space Lipschitz isomorphism almost periodicity Arzela-Ascoli theorem metric set

Hydraulics of a multiple slit-type energy dissipater

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Journal of Hydrodynamics 2014年第1期26卷 86-93页

作者：吴建华姚莉马飞吴伟伟 College of Water Conservancy and Hydropower Engineering Hohai University Hydraulic Structures Design Division Hydrochina Huadong Engineering Corporation

With the constructions of high dam projects in China, the energy dissipation downstream of a dam becomes a serious concern. In this study, a multiple slit-type energy dissipater, with different reduction size slits in the outlet, is developed on the basis of conventional slit-type energy dissipaters, aiming to enhance the energy dissipation through the turbulence and the friction between the different layers of the jet flow and the air entrainment due to the increased surface of the flow to the air. The hydraulic characteristics of the energy dissipater are experimentally investigated by means of three sets of physical models in nine cases, to characterize the geometric parameters with suitable performance. The main concerns are the flow regime, the jet flow trajectory, the energy dissipation, the cavitation characteristics, and the flow choking. The results indicate that the dissipater enjoys a high energy dissipation ratio with suitable hydraulic performance comparing with the conventional slit-type energy dissipaters.

关键词： aerator cavity length fin lateral deflector

Optimization of Hydrocracking Process for Enhanced BTX Production from Coal Tar-Derived Hydrorefined Products

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 139-151页

作者： wu Hao wei Hongyuan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

Hydroconversion of coal tar to produce aromatic hydrocarbons(BTX)represents a crucial strategy for the highvalue hierarchical utilization of *** study focused on the hydrocracking of hydrorefined products derived from coal tar to enhance the production of benzene,toluene,and xylene(BTX).Various reaction conditions,including reaction temperature,hydrogen pressure,space velocity,and hydrogen-to-oil volume ratio,were systematically explored to optimize BTX yields while also considering the process’s economic *** results indicate that increasing the reaction temperature from 360℃ to 390℃ significantly favors the production of BTX,with yields increasing from 21.42%to 41.14%.Similarly,an increase in hydrogen pressure from 4 MPa to 6 MPa boosts BTX production,with yields rising from 36.31%to 41.14%.Reducing the space velocity from 2 h^(-1) to 0.5 h^(-1) also favors the BTX production process,with yields increasing from 37.96%to 45.13%.Furthermore,raising the hydrogen-to-oil volume ratio from 750 to 1500 improves BTX yields from 41.61%to 45.44%.Through economic analysis,the optimal conditions for BTX production were identified as a reaction temperature of 390℃,hydrogen pressure of 5-6 MPa,space velocity of 1 h^(-1),and hydrogen-to-oil volume ratio of 1000,achieving a BTX yield of 43.73%.This investigation highlights the importance of a holistic evaluation of hydrocracking conditions to optimize BTX ***,the findings offer valuable insights for the design and operation of industrial hydrocracking processes aimed at efficiently converting coal tar-derived hydrorefined feedstock into BTX.

关键词： coal tar hydrocracking BTX process optimization economic assessment

Glial progenitor heterogeneity and plasticity in the adult spinal cord

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Neural Regeneration Research 2024年第12期19卷 2567-2568页

作者： Haichao wei Jia Qian wu Department of Neurosurgery McGovern Medical SchoolThe University of Texas Health Science Center at HoustonHoustonTXUSA Center for Stem Cell and Regenerative Medicine UT Brown Foundation Institute of Molecular MedicineHoustonTXUSA MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences HoustonTXUSA

Glial progenitor cells were reported to have the capacity to generate various types of cells in both the central nervous system(CNS)and peripheral nervous *** progenitor cells can respond to diverse environmental signals and transform into distinct populations,each serving specific ***,the adult spinal cord hosts various populations of glial progenitors,a region integral to the central nervous *** development,glial progenitors express glial fibrillary acidic protein(GFAP;Dimou and Gotz,2014).However,the specific identities of GFAP-expressing progenitors in the adult spinal cord were not thoroughly investigated.

关键词： functions plasticity thoroughly