期刊文献+
共找到128篇文章
< 1 2 7 >
每页显示 20 50 100
Surface Patterning of Metal Zinc Electrode with an In‑Region Zincophilic Interface for High‑Rate and Long‑Cycle‑Life Zinc Metal Anode 被引量:1
1
作者 tian wang Qiao Xi +8 位作者 Kai Yao Yuhang Liu Hao Fu Venkata Siva Kavarthapu Jun Kyu Lee Shaocong Tang Dina Fattakhova‑Rohlfing Wei Ai Jae Su Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期192-209,共18页
The undesirable dendrite growth induced by non-planar zinc(Zn)deposition and low Coulombic efficiency resulting from severe side reactions have been long-standing challenges for metallic Zn anodes and substantially im... The undesirable dendrite growth induced by non-planar zinc(Zn)deposition and low Coulombic efficiency resulting from severe side reactions have been long-standing challenges for metallic Zn anodes and substantially impede the practical application of rechargeable aqueous Zn metal batteries(ZMBs).Herein,we present a strategy for achieving a high-rate and long-cycle-life Zn metal anode by patterning Zn foil surfaces and endowing a Zn-Indium(Zn-In)interface in the microchannels.The accumulation of electrons in the microchannel and the zincophilicity of the Zn-In interface promote preferential heteroepitaxial Zn deposition in the microchannel region and enhance the tolerance of the electrode at high current densities.Meanwhile,electron aggregation accelerates the dissolution of non-(002)plane Zn atoms on the array surface,thereby directing the subsequent homoepitaxial Zn deposition on the array surface.Consequently,the planar dendrite-free Zn deposition and long-term cycling stability are achieved(5,050 h at 10.0 mA cm^(−2) and 27,000 cycles at 20.0 mA cm^(−2)).Furthermore,a Zn/I_(2) full cell assembled by pairing with such an anode can maintain good stability for 3,500 cycles at 5.0 C,demonstrating the application potential of the as-prepared ZnIn anode for high-performance aqueous ZMBs. 展开更多
关键词 Zn metal anode Surface patterning Directional Zn deposition Aqueous Zn-I_(2)batteries
下载PDF
球磨GNPs/SiO_(2)复合改性沥青流变性能和疲劳特性研究
2
作者 田旺 王宇航 +2 位作者 常亮亮 陈惠坤 牛冬瑜 《长沙理工大学学报(自然科学版)》 CAS 2024年第5期53-64,共12页
【目的】研究石墨烯纳米片(GNPs)和SiO_(2)复合改性沥青的流变性能和疲劳特性。【方法】本文以机械球磨法制备GNPs和SiO_(2)复合改性剂为核心,选取不同掺量的球磨GNPs/SiO_(2)复合改性剂,通过多应力蠕变恢复(multiple stress creep reco... 【目的】研究石墨烯纳米片(GNPs)和SiO_(2)复合改性沥青的流变性能和疲劳特性。【方法】本文以机械球磨法制备GNPs和SiO_(2)复合改性剂为核心,选取不同掺量的球磨GNPs/SiO_(2)复合改性剂,通过多应力蠕变恢复(multiple stress creep recovery,MSCR)试验、温度扫描试验、频率扫描试验和线性振幅扫描试验,分析球磨GNPs/SiO_(2)复合改性沥青的高温流变特性和疲劳特性,揭示球磨GNPs/SiO_(2)复合改性机理。【结果】球磨GNPs/SiO_(2)复合改性剂的加入,可使高应力水平重复荷载作用下的改性沥青抗变形能力得到明显改善。当复合改性剂掺量达到9‰时,球磨GNPs/SiO_(2)复合改性沥青的抗变形能力显著提高。在低应变水平下,球磨GNPs/SiO_(2)复合改性剂的添加有利于提高沥青的抗疲劳性能。【结论】球磨GNPs/SiO_(2)复合改性沥青相较于单一改性沥青在高应力水平重复荷载作用下的抗变形能力和低应变水平下的抗疲劳性能更优。 展开更多
关键词 道路建筑材料 球磨 石墨烯纳米片 纳米二氧化硅 复合改性沥青 流变性能
下载PDF
基于超声-微纳米气泡辅助技术的可变光程水质多参数检测方法研究
3
作者 李文 李德健 +6 位作者 马永跃 田旺 陈银银 王利民 吕赫 李杰 骆紫云 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第7期2037-2044,共8页
针对目前国家标准分析检测水质多参数方法存在的科学与技术问题,提出了一种基于超声-微纳米气泡(US-MNB)辅助技术、连续光谱法和顺序注射分析法(SIA)的可变光程水质多参数检测新方法。设计水质多参数检测系统,通过检测总磷(TP)、化学需... 针对目前国家标准分析检测水质多参数方法存在的科学与技术问题,提出了一种基于超声-微纳米气泡(US-MNB)辅助技术、连续光谱法和顺序注射分析法(SIA)的可变光程水质多参数检测新方法。设计水质多参数检测系统,通过检测总磷(TP)、化学需氧量(COD)、氨氮(NH_(3)-N)和六价铬(Cr^(6+))四种水质参数,验证了新方法的可行性。系统设计的核心是基于超声与微纳米气泡相结合的消解室以及具有可变光程功能的光谱扫描检测室,可达到快速消解和稳定检测的目的。同时系统基于国家水质检测标准,优化了水质多参数联合检测流程,并利用分光光度法和顺序注射分析技术对四种水质参数的含量进行连续光谱检测。首先,在常温常压下采用US-MNB辅助技术结合强氧化剂对TP进行消解,同时对检测室中NH_(3)-N参数显色反应后的化合物直接进行光谱扫描测定,消解后,再进行TP的测定。同理,消解COD的同时,对检测室中的Cr^(6+)参数显色反应后的化合物直接进行光谱扫描测定,消解后,再进行COD的测定。整个检测过程所用时间大幅降低,可在短时间内自动完成水质多参数的测定,显著地提高了检测的效率。以上述四种水质参数为测定对象,利用最小二乘法构建回归模型,拟合回归方程并计算相关系数,并绘制各参数的浓度-吸光度标准工作曲线。结果表明:TP标准工作曲线拟合系数≥0.9845,且浓度与吸光度成正相关,重复性(RSD)为3.05%~3.62%,加标回收率为97.8%~103.6%;COD标准工作曲线拟合系数≥0.9987,且浓度与吸光度成负相关,重复性(RSD)为2.12%~2.74%,加标回收率为98.7%~104.7%;NH_(3)-N标准工作曲线拟合系数≥0.9953,且浓度与吸光度成正相关,重复性(RSD)为3.41%~3.59%,加标回收率为99.2%~102.4%;Cr^(6+)标准工作曲线拟合系数≥0.9938,且浓度与吸光度成正相关,重复性(RSD)为3.51%~3.92%,加标回收率为98.9%~109.3%。系统可准确测定水样中TP、COD、NH_(3)-N和Cr^(6+)的含量,且具有良好的稳定性与可靠性。基于超声-微纳米气泡辅助技术的可变光程水质多参数检测方法研究,对于拓宽光谱法在水质多参数快速检测领域的应用以及提升检测效率等方面的研究具有重要作用。 展开更多
关键词 连续光谱 超声-微纳米气泡 顺序注射分析法 可变光程 多参数水质检测 联合检测
下载PDF
基于复杂因果关系模型的特征选择新方法及其在蜡油加氢工业装置上的应用
4
作者 田旺 秦康 +4 位作者 吴昊 李明丰 谢煜 张璠玢 梁家林 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第3期580-590,共11页
复杂因果关系模型的特征选择方法是当前人工智能领域的难点问题,开发新的特征选择方法对于因果关系模型的发展意义重大。以蜡油加氢工业装置为研究对象,针对模型涉及输入原料性质、操作参数等自变量特征和输出因变量特征精制蜡油硫含量... 复杂因果关系模型的特征选择方法是当前人工智能领域的难点问题,开发新的特征选择方法对于因果关系模型的发展意义重大。以蜡油加氢工业装置为研究对象,针对模型涉及输入原料性质、操作参数等自变量特征和输出因变量特征精制蜡油硫含量之间复杂的因果关系,综合考虑输入变量两两之间的关系和输入变量与输出变量之间的关系筛选出合适的特征。首先,分别求出自变量特征之间和自变量与因变量之间的相关关系;其次,设计阈值和判别函数,将自变量、因变量结合起来,综合考虑两类变量之间的关系,最终将蜡油原料馏程中的初馏点筛选出来并剔除。相比传统的相关性特征选择方法,新筛选特征模型预测精制蜡油硫质量分数的平均绝对误差(MAE)减少62.97μg/g,平均相对误差(MRE)减少2.02百分点,决定系数R 2增加0.395,充分说明了新特征筛选方法对复杂因果关系模型的有效性。 展开更多
关键词 蜡油加氢 硫含量 因果关系 相关关系 特征选择
下载PDF
An intelligent active probing and trace-back scheme for IoT anomaly detection
5
作者 Luying wang Lingyi Chen +3 位作者 Neal N.Xiong Anfeng Liu tian wang Mianxiong Dong 《Digital Communications and Networks》 SCIE CSCD 2024年第1期168-181,共14页
Due to their simple hardware,sensor nodes in IoT are vulnerable to attack,leading to data routing blockages or malicious tampering,which significantly disrupts secure data collection.An Intelligent Active Probing and ... Due to their simple hardware,sensor nodes in IoT are vulnerable to attack,leading to data routing blockages or malicious tampering,which significantly disrupts secure data collection.An Intelligent Active Probing and Trace-back Scheme for IoT Anomaly Detection(APTAD)is proposed to collect integrated IoT data by recruiting Mobile Edge Users(MEUs).(a)An intelligent unsupervised learning approach is used to identify anomalous data from the collected data by MEUs and help to identify anomalous nodes.(b)Recruit MEUs to trace back and propose a series of trust calculation methods to determine the trust of nodes.(c)The last,the number of active detection packets and detection paths are designed,so as to accurately identify the trust of nodes in IoT at the minimum cost of the network.A large number of experimental results show that the recruiting cost and average anomaly detection time are reduced by 6.5 times and 34.33%respectively,while the accuracy of trust identification is improved by 20%. 展开更多
关键词 Anomaly detection Internet of things Integrating data collection Mobile edge users INTELLIGENT
下载PDF
MXene Sediment-Based Poly(vinyl alcohol)/Sodium Alginate Aerogel Evaporator with Vertically Aligned Channels for Highly Efficient Solar Steam Generation
6
作者 tian wang Meng Li +12 位作者 Hongxing Xu Xiao wang Mingshu Jia Xianguang Hou Shuai Gao Qingman Liu Qihang Yang Mingwei tian Lijun Qu Zhenhua Song Xiaohu Wu Lili wang Xiansheng Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期638-654,共17页
Solar-driven interfacial evaporation from seawater is considered an effective way to alleviate the emerging freshwater crisis because of its green and environmentally friendly characteristics.However,developing an eva... Solar-driven interfacial evaporation from seawater is considered an effective way to alleviate the emerging freshwater crisis because of its green and environmentally friendly characteristics.However,developing an evaporator with high efficiency,stability,and salt resistance remains a key challenge.MXene,with an internal photothermal conversion efficiency of 100%,has received tremendous research interest as a photothermal material.However,the process to prepare the MXene with monolayer is inefficient and generates a large amount of“waste”MXene sediments(MS).Here,MXene sediments is selected as the photothermal material,and a three-dimensional MXene sediments/poly(vinyl alcohol)/sodium alginate aerogel evaporator with vertically aligned pores by directional freezing method is innovatively designed.The vertical porous structure enables the evaporator to improve water transport,light capture,and high evaporation rate.Cotton swabs and polypropylene are used as the water channel and support,respectively,thus fabricating a self-floating evaporator.The evaporator exhibits an evaporation rate of 3.6 kg m^(-2)h^(-1)under one-sun illumination,and 18.37 kg m^(-2)of freshwater is collected in the condensation collection device after 7 h of outdoor sun irradiation.The evaporator also displays excellent oil and salt resistance.This research fully utilizes“waste”MS,enabling a self-floating evaporation device for freshwater collection. 展开更多
关键词 MXene sediments Porous structure DESALINATION Self-floating
下载PDF
无源微混合器研究进展
7
作者 谢煜 田旺 +1 位作者 张杨 秦康 《现代化工》 CAS CSCD 北大核心 2024年第5期82-87,共6页
介绍了基于层压的微混合器、基于障碍物的微混合器、基于收敛-发散的微混合器和基于弯曲通道的微混合器等4种主要的无源微混合器研究进展,深入分析了各自的结构特点、混合特性、优缺点及适宜的应用场景。在此基础上,对无源微混合器的主... 介绍了基于层压的微混合器、基于障碍物的微混合器、基于收敛-发散的微混合器和基于弯曲通道的微混合器等4种主要的无源微混合器研究进展,深入分析了各自的结构特点、混合特性、优缺点及适宜的应用场景。在此基础上,对无源微混合器的主要制造技术进行了归纳,未来3D打印等新型增材制造技术的发展将会高效赋能微流控元件的大规模制造和集成化应用。最后展望了无源微混合器的发展方向。 展开更多
关键词 无源微混合器 微尺度 多相流 应用场景 制造
下载PDF
Correction: Surface Patterning of Metal ZincElectrode with an In-Region Zincophilic Interfacefor High-Rate and Long-Cycle-Life Zinc MetalAnode
8
作者 tian wang Qiao Xi +8 位作者 Kai Yao Yuhang Liu Hao Fu Venkata Siva Kavarthapu Jun Kyu Lee Shaocong Tang Dina Fattakhova-Rohlfing Wei Ai Jae Su Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期456-457,共2页
Correction to:Nano-Micro Letters(2024)16:112 https://doi.org/10.1007/s40820-024-01327-2 In the supplementary information the following corrections have been carried out:1.Institute of Energy and Climate Research,Mater... Correction to:Nano-Micro Letters(2024)16:112 https://doi.org/10.1007/s40820-024-01327-2 In the supplementary information the following corrections have been carried out:1.Institute of Energy and Climate Research,Materials Synthesis and Processing,Forschungszentrum Jülich GmbH,52425 Jülich,Germany.Corrected:Institute of Energy and Climate Research:Materials Synthesis and Processing(IEK-1),Forschungszentrum Jülich GmbH,52425 Jülich,Germany. 展开更多
关键词 CORRECTION ZINC ELECTRODE
下载PDF
大直径不锈钢管内旋压成形的金属流动堆积缺陷研究
9
作者 田旺 王琛 +1 位作者 张斌凯 李维壮 《钢管》 CAS 2024年第2期28-33,共6页
采用Abaqus软件仿真分析大直径不锈钢管在内旋压成形过程中的金属流动堆积现象。采用单因素控制法讨论了壁厚分别为20 mm、12 mm和7 mm时Ф508 mm不锈钢管在三旋轮内旋压过程中的等效应变、金属流动及旋轧力的变化规律,并分析了不同厚... 采用Abaqus软件仿真分析大直径不锈钢管在内旋压成形过程中的金属流动堆积现象。采用单因素控制法讨论了壁厚分别为20 mm、12 mm和7 mm时Ф508 mm不锈钢管在三旋轮内旋压过程中的等效应变、金属流动及旋轧力的变化规律,并分析了不同厚度时层间金属质点的流动速度,进一步得出金属流动堆积的原因。结果表明:随着初始壁厚值的不断减小,壁厚为7 mm时,旋轮前方产生的金属堆积高度达到9 mm,接触区的等效应变值最大达到7.9,产生的旋轧力高达450 kN。可见,在相同工况下,钢管的壁厚越小,接触区的等效应变值越大,所需旋压力也越大,产生的金属堆积现象越严重。 展开更多
关键词 不锈钢管 内旋压 金属流动 堆积 等效应变 旋压力
下载PDF
芪苈强心胶囊对急性左心衰竭患者血管内皮功能及心功能指标的影响
10
作者 田旺 章蕾蕾 《中国医学创新》 CAS 2024年第32期63-66,共4页
目的:探讨芪苈强心胶囊对急性左心衰竭患者血管内皮功能及心功能指标的影响。方法:按随机数字表法将2021年1月—2023年12月在萍乡赣西医院接受治疗的80例急性左心衰竭患者分为两组,每组40例。对照组采用重组人脑利钠肽治疗,观察组在对... 目的:探讨芪苈强心胶囊对急性左心衰竭患者血管内皮功能及心功能指标的影响。方法:按随机数字表法将2021年1月—2023年12月在萍乡赣西医院接受治疗的80例急性左心衰竭患者分为两组,每组40例。对照组采用重组人脑利钠肽治疗,观察组在对照组基础上加用芪苈强心胶囊治疗。对比两组中医证候疗效、血管内皮功能、心功能指标和不良反应发生情况。结果:观察组治疗总有效率高于对照组(P<0.05);观察组治疗后内皮素-1(ET-1)低于对照组,一氧化氮(NO)、充血肱动脉内径增加度(FMD)水平均高于对照组(P<0.05);观察组治疗后左心室舒张末期容积(LVEDV)、左心室收缩末期容积(LVESV)均低于对照组,左心室射血分数(LVEF)高于对照组(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:芪苈强心胶囊在急性左心衰竭患者治疗中效果显著,能够改善患者血管内皮功能,可有效促进患者心功能水平恢复,利于缓解患者中医证候,且副作用较少,安全性较高。 展开更多
关键词 急性左心衰竭 芪苈强心胶囊 血管内皮功能 心功能指标
下载PDF
Optical molecular imaging in cancer research:current impact and future prospect
11
作者 Yinuo Li Zihan Li +4 位作者 Yuting Li Xiaofan Gao tian wang Xiangyi Ma Mingfu Wu 《Oncology and Translational Medicine》 CAS 2024年第5期212-222,共11页
Cancer has long been amajor threat to human health.Recent advancements inmolecular imaging have revolutionized cancer research by enabling early and precise disease localization,essential for effective management.In p... Cancer has long been amajor threat to human health.Recent advancements inmolecular imaging have revolutionized cancer research by enabling early and precise disease localization,essential for effective management.In particular,optical molecular imaging is an invaluable cancer detection tool in preoperative planning,intraoperative guidance,and postoperative monitoring owing to its noninvasive nature,rapid turnover,safety,and ease of use.The tumor microenvironment and cells within it express distinct biomarkers.Optical imaging technology leverages these markers to differentiate tumor tissues from surrounding tissues and capture real-time images with high resolution.Nevertheless,a robust understanding of these cancer-relatedmolecules and their dynamic changes is crucial for effectivelymanaging cancer.Recent advancements in opticalmolecular imaging technologies offer novel approaches for cancer investigation in research and practice.This review investigates themodern opticalmolecular imaging techniques employed in both preclinical and clinical research,including bioluminescence,fluorescence,chemiluminescence,photoacoustic imaging,and Raman spectroscopy.We explore the current paradigm of optical molecular imaging modalities,their current status in preclinical cancer research and clinical applications,and future perspectives in the fields of cancer research and treatment. 展开更多
关键词 CANCER Opticalmolecular imaging Bioluminescence imaging FLUORESCENCE CHEMILUMINESCENCE Photoacoustic imaging Raman spectroscopy
下载PDF
4UPS-RPS并联机器人工作空间分析及参数优化
12
作者 杨智勇 汪浩洋 +1 位作者 田望 刘旭 《制造业自动化》 2024年第10期91-99,共9页
针对一种4UPS-RPS并联机器人,为增大该机器人的工作空间,对其进行工作空间分析和结构参数优化。首先进行机器人的运动学分析,确定动平台的姿态和驱动分支之间的映射关系。然后利用数值法和MATLAB软件求解机器人工作空间体积。接着通过... 针对一种4UPS-RPS并联机器人,为增大该机器人的工作空间,对其进行工作空间分析和结构参数优化。首先进行机器人的运动学分析,确定动平台的姿态和驱动分支之间的映射关系。然后利用数值法和MATLAB软件求解机器人工作空间体积。接着通过单一因素分析法和正交实验法共同分析并联机器人各种结构参数对其工作空间体积的影响,结果表明各参数影响程度由大到小分别为:驱动分支杆长最大值、转动副转角范围、驱动分支杆长最小值、动平台半径,且当驱动分支杆长最小值为340 mm,最大值为640 mm,动平台半径为140 mm,转动副转角为±52°时得到最大工作体积为2.49×10~7 mm3,较优化前提高了107.5%。最后建立样机进行实验,证明了建立模型的正确性。4UPS-RPS并联机器人工作空间分析及参数优化为提高机器人的工作能力提供了重要的基础保证。 展开更多
关键词 并联机器人 工作空间分析 MATLAB仿真 单因素分析法 正交实验法
下载PDF
麝香保心丸对慢性心功能不全急性加重患者血管内皮功能及心功能的影响
13
作者 田旺 章蕾蕾 《江西中医药》 CAS 2024年第11期34-36,共3页
目的:探究麝香保心丸对慢性心功能不全(CCI)急性加重患者血管内皮功能及心功能的影响。方法:择取2021年1月—2023年8月在萍乡赣西医院治疗的CCI急性加重患者94例,随机分成观察组和对照组,各47例。对照组予西医常规治疗,观察组在此基础... 目的:探究麝香保心丸对慢性心功能不全(CCI)急性加重患者血管内皮功能及心功能的影响。方法:择取2021年1月—2023年8月在萍乡赣西医院治疗的CCI急性加重患者94例,随机分成观察组和对照组,各47例。对照组予西医常规治疗,观察组在此基础上予麝香保心丸治疗。比较2组心功能、血管内皮功能和炎症反应。结果:治疗后,2组心输出量(CO)与左室射血分数(LVEF)均升高,左室舒张末容积(LVEDV)均降低,且观察组CO、LVEF高于对照组,LVEDV低于对照组,差异均有统计学意义(P<0.05);2组内皮素-1(ET-1)均降低,一氧化氮(NO)均升高,且观察组ET-1低于对照组,NO高于对照组,差异均有统计学意义(P<0.05);2组肿瘤坏死因子-α(TNF-α)、超敏C反应蛋白(hs-CRP)、白介素-6(IL-6)水平均降低,且观察组IL-6、hs-CRP、TNF-α低于对照组,差异均有统计学意义(P<0.05)。结论:麝香保心丸用于CCI急性加重患者,可改善血管内皮功能,降低炎症反应,提高心功能。 展开更多
关键词 慢性心功能不全 麝香保心丸 血管内皮功能 心功能
下载PDF
Observational Subseasonal Variability of the PM_(2.5) Concentration in the Beijing-Tianjin-Hebei Area during the January 2021 Sudden Stratospheric Warming 被引量:1
14
作者 Qian LU Jian RAO +4 位作者 Chunhua SHI Dong GUO Ji wang Zhuoqi LIANG tian wang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第10期1623-1636,共14页
It is still not well understood if subseasonal variability of the local PM_(2.5) in the Beijing-Tianjin-Hebei(BTH)region is affected by the stratospheric state.Using PM_(2.5) observations and the ERA5 reanalysis,the e... It is still not well understood if subseasonal variability of the local PM_(2.5) in the Beijing-Tianjin-Hebei(BTH)region is affected by the stratospheric state.Using PM_(2.5) observations and the ERA5 reanalysis,the evolution of the air quality in BTH during the January 2021 sudden stratospheric warming(SSW)is explored.The subseasonal variability of the PM_(2.5) concentration after the SSW onset is evidently enhanced.Stratospheric circumpolar easterly anomalies lasted for 53 days during the January-February 2021 SSW with two evident stratospheric pulses arriving at the ground.During the tropospheric wave weakening period and the intermittent period of dormant stratospheric pulses,the East Asian winter monsoon weakened,anomalous temperature inversion developed in the lower troposphere,anomalous surface southerlies prevailed,atmospheric moisture increased,and the boundary layer top height lowered,all of which favor the accumulation of pollutant particulates,leading to two periods of pollution processes in the BTH region.In the phase of strengthened East Asian winter monsoon around the very beginning of the SSW and another two periods when stratospheric pulses had reached the near surface,opposite-signed circulation patterns and meteorological conditions were observed,which helped to dilute and diffuse air pollutants in the BTH region.As a result,the air quality was excellent during the two periods when the stratospheric pulse had reached the near surface.The increased subseasonal variation of the regional pollutant particulates after the SSW onset highlights the important role of the stratosphere in the regional environment and provides implications for the environmental prediction. 展开更多
关键词 sudden stratospheric warming(SSW) PM_(2.5) Beijing-Tianjin-Hebei(BTH) East Asian winter monsoon boundary layer meteorological conditions
下载PDF
Analysis of Clinical Characteristics and Risk Factors of Pseudomonas aeruginosa Bloodstream Infection in 55 Cases
15
作者 Pengpeng tian Shanshan Su +3 位作者 tian wang Lisa Zhu Wen Fan Huawei Yi 《Yangtze Medicine》 2023年第3期162-170,共9页
Objective: Pseudomonas aeruginosa bloodstream infection presents a severe challenge to hospitalized patients. To investigate the clinical characteristics, risk factors and drug resistance of Pseudomonas aeruginosa blo... Objective: Pseudomonas aeruginosa bloodstream infection presents a severe challenge to hospitalized patients. To investigate the clinical characteristics, risk factors and drug resistance of Pseudomonas aeruginosa bloodstream infection. Methods: Clinical data and laboratory results of patients with Pseudomonas aeruginosa bloodstream infection in the First Affiliated Hospital of Yangtze University from January 2019 to December 2022 were retrospectively analyzed. The factors associated with infection and death were analyzed by univariate analysis. Results: A total of 55 patients were enrolled in this study, The 28-day mortality rate was 14.5%. Univariate analysis showed that high procalcitonin, low albumin, ICU admission, central venous catheterization, indwelling catheter, and mechanical ventilation were associated with death. Multivariate Logistic regression analysis showed that hypoproteinemia and central venous catheters were independent risk factors for death in patients with Pseudomonas aeruginosa bloodstream infection. Conclusions: The drug resistance of P. aeruginosa bloodstream infection is not high, but the fatality rate is high. The combination of hypoalbuminemia after the onset of the disease and the use of central vein catheters can lead to increased mortality, suggesting that clinical identification of high-risk patients as early as possible, reducing the use of catheters, preventing the occurrence of P. aeruginosa bloodstream infection and improving the prognosis. 展开更多
关键词 Pseudomonas aeruginosa Bloodstream Infections RESISTANCE Risk Factors
下载PDF
一种S频段反射型可调模拟移相器的设计
16
作者 赵来定 万梦军 +2 位作者 张更新 田旺 廉佳鹏 《微电子学》 CAS 北大核心 2023年第2期241-246,共6页
设计了一种应用于S频段卫星通信相控阵系统的反射型可调模拟移相器。该移相器利用三分支线定向耦合器扩展了带宽,改善了工作频段内驻波;采用传输线和变容二极管构成的L型反射负载扩大了相移量。测试结果表明,在上行频段1.98~2.01 GHz内... 设计了一种应用于S频段卫星通信相控阵系统的反射型可调模拟移相器。该移相器利用三分支线定向耦合器扩展了带宽,改善了工作频段内驻波;采用传输线和变容二极管构成的L型反射负载扩大了相移量。测试结果表明,在上行频段1.98~2.01 GHz内,相移量达到191°±1°,在下行频段2.17~2.2 GHz内,相移量达到186°±0.1°;插入损耗优于3.3 dB且插入损耗波动小于1 dB,回波损耗在整个电压调谐范围内均大于20 dB。该移相器结构简单、便于调节且价格低廉,在卫星通信领域有一定的应用价值。 展开更多
关键词 S频段 反射型移相器 三分支线定向耦合器 变容二极管
下载PDF
大功率量子级联激光器的光学与热学协同优化设计 被引量:2
17
作者 杨若珂 张东亮 +5 位作者 郑显通 田旺 柳渊 鹿利单 祝连庆 王伟平 《激光与红外》 CAS CSCD 北大核心 2023年第9期1350-1359,共10页
针对大功率量子级联激光器存在热积累严重的问题,本文基于MBE与MOCVD结合的二次外延生长InP基量子级联激光器结构的工艺方法,设计优化中波单管4W连续光输出的大功率量子级联激光器光学与散热性能。通过COMSOL软件对器件结构进行建模,设... 针对大功率量子级联激光器存在热积累严重的问题,本文基于MBE与MOCVD结合的二次外延生长InP基量子级联激光器结构的工艺方法,设计优化中波单管4W连续光输出的大功率量子级联激光器光学与散热性能。通过COMSOL软件对器件结构进行建模,设计器件光学和热学结构模型,分析不同结构参数对器件性能的影响,得到最优结构参数:在In053Ga047As层厚度为50nm,波导下包层InP为1μm,上包层InP为2μm,封装金层厚度为3μm时,器件光学和热学综合性能最优,其中波导光限制因子为074,核心区温度为378 K。本文研究相关结论可为后续大功率中波量子级联激光器结构与工艺设计提供指导。 展开更多
关键词 量子级联激光器 二次外延 波导结构 热学结构 协同优化
下载PDF
浅水湖泊底泥细菌群落的时空分布特征及主要营养盐驱动因素
18
作者 钟美芳 张化永 +3 位作者 王华林 王中玉 田旺 黄头生 《地球与环境》 CAS CSCD 北大核心 2023年第4期377-387,共11页
为探究富营养化浅水湖泊底泥中细菌群落的结构特征及驱动因素,本研究以安徽八里河湖为例,通过16S rRNA高通量测序手段并结合底泥的营养盐理化性质,分析了底泥细菌群落物种组成和多样性的时空分布特征以及与营养盐的相关性关系。结果显示... 为探究富营养化浅水湖泊底泥中细菌群落的结构特征及驱动因素,本研究以安徽八里河湖为例,通过16S rRNA高通量测序手段并结合底泥的营养盐理化性质,分析了底泥细菌群落物种组成和多样性的时空分布特征以及与营养盐的相关性关系。结果显示:(1)在物种组成方面,γ-变形菌纲(Gammaproteobacteria),δ-变形菌纲(Deltaproteobacteria)和拟杆菌纲(Bacteroidia)是八里河湖底泥中的优势菌纲,它们在空间上呈均质性和在季节上有稳定性;(2)在群落结构方面,底泥细菌群落整体上以季节进行聚类,呈现了季节内的相似性和季节间的差异性,且可能来自于鱼类粪便的Clostridia菌纲在八里河湖底泥细菌群落结构差异的塑造上有重要贡献;(3)从四个季节所有样品的整体角度来看,与磷相关的指标(总磷、铁铝结合态磷、钙磷、有机磷)对细菌群落变化的解释最强(r=0.23~0.45,p<0.001),且底泥细菌群落之间的差异性随各磷指标内部之间差异的增大而增大。本研究的发现为认识和理解富营养化浅水湖泊中底泥细菌群落特征及其驱动因素提供了新的信息,对湖泊生态系统健康状态的监测和评估有重要意义。 展开更多
关键词 16S rRNA 富营养化湖泊 群落结构 物种组成
下载PDF
Supplemental Clostridium butyricum modulates lipid metabolism by reshaping the gut microbiota composition and bile acid profile in IUGR suckling piglets 被引量:6
19
作者 Xin Zhang Yang Yun +7 位作者 Zheng Lai Shuli Ji Ge Yu Zechen Xie Hao Zhang Xiang Zhong tian wang Lili Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1150-1166,共17页
Background Intrauterine growth restriction(IUGR)can cause lipid disorders in infants and have long-term adverse effects on their growth and development.Clostridium butyricum(C.butyricum),a kind of emerging probiotics,... Background Intrauterine growth restriction(IUGR)can cause lipid disorders in infants and have long-term adverse effects on their growth and development.Clostridium butyricum(C.butyricum),a kind of emerging probiotics,has been reported to effectively attenuate lipid metabolism dysfunctions.Therefore,the objective of this study was to investigate the effects of C.butyricum supplementation on hepatic lipid disorders in IUGR suckling piglets.Methods Sixteen IUGR and eight normal birth weight(NBW)neonatal male piglets were used in this study.From d 3to d 24,in addition to drinking milk,the eight NBW piglets(NBW-CON group,n=8)and eight IUGR piglets(IUGR-CON group,n=8)were given 10 mL sterile saline once a day,while the remaining IUGR piglets(IUGR-CB group,n=8)were orally administered C.butyricum at a dose of 2×108colony-forming units(CFU)/kg body weight(suspended in 10 mL sterile saline)at the same frequency.Results The IUGR-CON piglets exhibited restricted growth,impaired hepatic morphology,disordered lipid metabolism,increased abundance of opportunistic pathogens and altered ileum and liver bile acid(BA)profiles.However,C.butyricum supplementation reshaped the gut microbiota of the IUGR-CB piglets,characterized by a decreased abundance of opportunistic pathogens in the ileum,including Streptococcus and Enterococcus.The decrease in these bile salt hydrolase(BSH)-producing microbes increased the content of conjugated BAs,which could be transported to the liver and function as signaling molecules to activate liver X receptorα(LXRα)and farnesoid X receptor(FXR).This activation effectively accelerated the synthesis and oxidation of fatty acids and down-regulated the total cholesterol level by decreasing the synthesis and promoting the efflux of cholesterol.As a result,the growth performance and morphological structure of the liver improved in the IUGR piglets.Conclusion These results indicate that C.butyricum supplementation in IUGR suckling piglets could decrease the abundance of BSH-producing microbes(Streptococcus and Enterococcus).This decrease altered the ileum and liver BA profiles and consequently activated the expression of hepatic LXRαand FXR.The activation of these two signaling molecules could effectively normalize the lipid metabolism and improve the growth performance of IUGR suckling piglets. 展开更多
关键词 Bile acid Clostridium butyricum Gut microbiota Intrauterine growth restriction Lipid metabolism Suckling piglet
下载PDF
Self-Modifying Nanointerface Driving Ultrahigh Bidirectional Thermal Conductivity Boron Nitride-Based Composite Flexible Films 被引量:2
20
作者 Taoqing Huang Xinyu Zhang +5 位作者 tian wang Honggang Zhang Yongwei Li Hua Bao Min Chen Limin Wu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第1期14-24,共11页
While boron nitride(BN) is widely recognized as the most promising thermally conductive filler for rapidly developing high-power electronic devices due to its excellent thermal conductivity and dielectric properties,a... While boron nitride(BN) is widely recognized as the most promising thermally conductive filler for rapidly developing high-power electronic devices due to its excellent thermal conductivity and dielectric properties,a great challenge is the poor vertical thermal conductivity when embedded in composites owing to the poor interracial interaction causing severe phonon scattering.Here,we report a novel surface modification strategy called the "self-modified nanointerface" using BN nanocrystals(BNNCs) to efficiently link the interface between BN and the polymer matrix.Combining with ice-press assembly method,an only 25 wt% BNembedded composite film can not only possess an in-plane thermal conductivity of 20.3 W m-1K-1but also,more importantly,achieve a through-plane thermal conductivity as high as 21.3 W m-1K-1,which is more than twice the reported maximum due to the ideal phonon spectrum matching between BNNCs and BN fillers,the strong interaction between the self-modified fillers and polymer matrix,as well as ladder-structured BN skeleton.The excellent thermal conductivity has been verified by theoretical calculations and the heat dissipation of a CPU.This study provides an innovative design principle to tailor composite interfaces and opens up a new path to develop high-performance composites. 展开更多
关键词 Thermal management materials Boron nitride Thermal conductivity Interfacial thermal resistance
下载PDF
上一页 1 2 7 下一页 到第
使用帮助 返回顶部