期刊文献+
共找到208篇文章
< 1 2 11 >
每页显示 20 50 100
A 700 W·h·kg^(-1) Rechargeable Pouch Type Lithium Battery 被引量:1
1
作者 李泉 杨旸 +1 位作者 禹习谦 李泓 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第4期85-90,共6页
High-energy-density rechargeable lithium batteries are being pursued by researchers because of their revolutionary potential nature.Current advanced practical lithium-ion batteries have an energy density of around300 ... High-energy-density rechargeable lithium batteries are being pursued by researchers because of their revolutionary potential nature.Current advanced practical lithium-ion batteries have an energy density of around300 W·h·kg^(-1).Continuing to increase the energy density of batteries to a higher level could lead to a major explosion development in some fields,such as electric aviation.Here,we have manufactured practical pouch-type rechargeable lithium batteries with both a gravimetric energy density of 711.3 W·h·kg^(-1)and a volumetric energy density of 1653.65 W·h·L^(-1).This is achieved through the use of high-performance battery materials including high-capacity lithium-rich manganese-based cathode and thin lithium metal anode with high specific energy,combined with extremely advanced process technologies such as high-loading electrode preparation and lean electrolyte injection.In this battery material system,the structural stability of cathode material in a widened charge/discharge voltage range and the deposition/dissolution behavior of interfacial modified thin lithium electrode are studied. 展开更多
关键词 BATTERY BATTERY LITHIUM
下载PDF
Quantitative morphometric analysis of a deep-water channel in the Taranaki Basin, New Zealand
2
作者 Wei Wu Guangxu Wang +4 位作者 Changsong lin Weiqing liu quan li Zhendong Feng Shuyuan Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期42-56,共15页
The morphological changes of deep-water channels have an important influence on the distributions of channel sand reservoirs,so it is important to explore the morphological change process of deep-water channel for the... The morphological changes of deep-water channels have an important influence on the distributions of channel sand reservoirs,so it is important to explore the morphological change process of deep-water channel for the exploration and development of deep-water oil and gas.Based on a typical sinuous Quaternary channel(Channel I)in the Taranaki Basin,New Zealand,a variety of seismic interpretation techniques were applied to quantitatively characterize the morphological characteristics of the Channel I,and the relationships between the quantitative parameters and the morphological changes of the Channel I,as well as the controlling factors affecting those morphological changes,were discussed.The results are as follows:(1)in the quantitative analysis,six parameters were selected:the channel depth,width,sinuosity,and aspect ratio(width/depth),the channel swing amplitude(λ)and the channel bend frequency(ω);(2)according to the quantitative morphological parameters of the channel(mainly including three parameters such as channel sinuosity,ωandλ),the Channel I was divided into three types:the low-sinuous channel(LSC),the high-sinuous channel(HSC),the moderate-sinuous channel(MSC).U-shaped channel cross-sections developed in the LSC,V-shaped channel cross-sections developed in the HSC,including inclined-V and symmetric-V cross-sections,and dish-shaped channel cross-sections developed in the MSC;(3)the morphological characteristics of the LSC and MSC were related to their widths and depths,while the morphology of the HSC was greatly affected by the channel width,a change in depth did not affect the HSC morphology;(4)the morphological changes of the Channel I were controlled mainly by the slope gradient,the restricted capacity of the channel and the differential in fluid properties. 展开更多
关键词 QUATERNARY deep-water channel geometrical morphology quantitative analysis Taranaki Basin New Zealand
下载PDF
Sedimentary elements,evolutions and controlling factors of the Miocene channel system:a case study of the deep-water Taranaki Basin in New Zealand
3
作者 Guangxu Wang Wei Wu +5 位作者 Changsong lin quan li Xiaoming Zhao Yongsheng Zhou Weiqing liu Shiqin liang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期44-58,共15页
Deep-water channel systems are important petroleum reservoirs,and many have been discovered worldwide.Understanding deep-water channel sedimentary elements and evolution is helpful for deep-sea petroleum exploration a... Deep-water channel systems are important petroleum reservoirs,and many have been discovered worldwide.Understanding deep-water channel sedimentary elements and evolution is helpful for deep-sea petroleum exploration and development.Based on high-resolution 3D seismic data,the Miocene channel system in the deep-water Taranaki Basin,New Zealand,was analyzed by using seismic interpretation techniques such as interlayer attribute extraction and strata slicing.The channel system was divided into five composite channels(CC-I to CC-V)according to four secondary level channel boundaries,and sedimentary elements such as channels,slump deposits,inner levees,mass transport deposits,and hemipelagic drape deposits were identified in the channel system.The morphological characteristics of several composite channels exhibited stark variances,and the overall morphology of the composite channels changed from relatively straight to highly sinuous to relatively straight.The evolution of the composite channels involved a gradual and repeated process of erosion and filling,and the composite channels could be divided into three evolutionary stages:initial erosion-filling,later erosion-filling(multistage),and channel abandonment.The middle Miocene channel system may have formed as a consequence of combined regional tectonic activity and global climatic change,and its intricate morphological alterations may have been influenced by the channel's ability to self-regulate and gravity flow properties.When studying the sedimentary evolution of a large-scale deep-water channel system in the Taranaki Basin during the Oligocene-Miocene,which transitioned from a passive margin to plate convergence,it can be understood how tectonic activity affected the channel and can also provide a theoretical reference for the evolution of the deepwater channels in areas with similar tectonic conversion environments around the world. 展开更多
关键词 deep-water channel system channel geomorphology sedimentary evolution climate and region tectonic activities deep-water Taranaki Basin
下载PDF
Mendelian randomization study to investigate the causal relationship between plasma homocysteine and chronic obstructive pulmonary disease
4
作者 Yanlan Hu Ping Tan +8 位作者 Juntao Wang Jun Zeng quan li Shijiao Yan Wenjie Hao Lanfen He Xingyue Song Caihong Zhang Chuanzhu Lyu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第5期367-371,共5页
BACKGROUND:Several observational studies have shown an association between homocysteine(Hcy)levels and chronic obstructive pulmonary disease(COPD),but causal relationships are not clear.Our study aimed to explore the ... BACKGROUND:Several observational studies have shown an association between homocysteine(Hcy)levels and chronic obstructive pulmonary disease(COPD),but causal relationships are not clear.Our study aimed to explore the causal relationship between plasma Hcy and COPD by two-sample Mendelian randomization(MR).METHODS:A two-sample MR study was performed to infer the causal link.Genetically predicted plasma Hcy was selected as an instrumental variable(Ⅳ)from published genome-wide association study(GWAS)meta-analyses.COPD with different etiologies was extracted as outcome variables from other GWAS meta-analyses.The main MR analysis was performed using the inversevariance weighted(IVW)method.Additional analyses were further performed using Cochran’s Q-test and MR-Egger regression to evaluate the heterogeneity or horizontal pleiotropy of our findings.RESULTS:MR analysis showed no significant association between plasma Hcy and COPD.The results of the groups were consistent with the sensitivity analysis and repeated analysis,without heterogeneity or horizontal pleiotropy.The IVW results showed COPD hospital admissions(odds ratio[OR]1.06,95%confidence interval[CI]0.91-1.24,P=0.42),asthma/COPD(OR 0.97,95%CI0.89-1.06,P=0.55),COPD-related chronic infection(OR 1.50,95%CI 0.57-3.99,P=0.41),COPDI asthma/interstitial lung disease(ILD)-related pneumonia or pneumonia-derived septicemia(OR 0.93,95%CI 0.86-1.02,P=0.13),and COPD-related respiratory insufficiency(OR 1.00,95%CI 0.7-1.44,P=0.99).CONCLUSION:There is no direct causal relationship between plasma Hcy and COPD in our study.As Hcy is known to have deleterious effects on endothelial function and vascular homeostasis,further studies are needed to investigate whether additional factors mediate the association between Hcy and COPD. 展开更多
关键词 HOMOCYSTEINE Chronic obstructive pulmonary disease Mendelian randomization
下载PDF
站城融合理念下高铁站点换乘导视系统优化设计研究
5
作者 丁楠 赵青青 +1 位作者 全利 王玖 《包装工程》 CAS 北大核心 2024年第10期450-459,468,共11页
目的本文以重庆建设国际性综合交通枢纽城市为研究背景,满足各类人群高铁出行的适宜性与多样性需求,升级城市形象展示窗口。深入剖析高铁站点导视系统在换乘枢纽中的实际应用情况,紧密关注城市智慧交通导视系统的发展趋势与最新动态,致... 目的本文以重庆建设国际性综合交通枢纽城市为研究背景,满足各类人群高铁出行的适宜性与多样性需求,升级城市形象展示窗口。深入剖析高铁站点导视系统在换乘枢纽中的实际应用情况,紧密关注城市智慧交通导视系统的发展趋势与最新动态,致力于解决用户在换乘过程中可能遇到的视觉困扰和引导不足等核心问题,并在此基础上提出具有针对性的优化设计方案。方法对城市高铁站轨道换乘导视系统的设计要点和布设方法进行举证研究,重点就城市智慧出行、数字导视系统进行分析,结合对乘客空间寻路、安全感、舒适感等心理需求的调研,总结轨道交通换乘站点导视系统的设计思路。综合考虑色彩及应用、字号及对比度、字体及视觉度、布设逻辑与信息分级,把控导视系统的视觉度、布设尺度、色彩材质、技术工艺。结合我国高铁站轨道换乘导视系统的发展现状,提出重庆西站换乘导视系统的优化设计策略。结论在尊重空间动向、用户体验、视觉流程的基础上,以智慧交通导视系统为研究对象,充分探寻高铁站点轨道换乘导视系统的高效性、便捷性,旨在提升枢纽的建设水平、运行效率,以及人民群众的出行体验。 展开更多
关键词 导视系统 高铁站点 出行体验 换乘能效
下载PDF
川东南地区中二叠统茅口组三段白云岩成因机理
6
作者 杨浩 潘磊 +5 位作者 全力 李让彬 王广伟 高俊杰 周玲 徐芮 《石油实验地质》 CAS CSCD 北大核心 2024年第2期311-318,共8页
白云岩是四川盆地海相层系最为重要的天然气储层类型之一,也是深层碳酸盐岩油气勘探的重点,白云岩成因机理的研究是预测深层优质白云岩储层分布的基础。通过川东南地区茅口组三段白云岩露头、岩心、薄片等资料,结合碳氧同位素、锶同位... 白云岩是四川盆地海相层系最为重要的天然气储层类型之一,也是深层碳酸盐岩油气勘探的重点,白云岩成因机理的研究是预测深层优质白云岩储层分布的基础。通过川东南地区茅口组三段白云岩露头、岩心、薄片等资料,结合碳氧同位素、锶同位素、稀土元素等研究了白云岩的成因机理。川东南地区茅三段白云岩可分为层状粉晶白云岩、层状细—中晶白云岩以及鞍形白云石胶结物。层状细—中晶白云岩是最主要的白云岩类型,未受热液影响的该类型白云岩δ^(18)O_(VPDB)值为-7.04‰~-6.08‰,与泥晶灰岩相似,^(87)Sr/^(86)Sr比值为0.707 550~0.707 740,处于同期海水范围值内,主要成因为准同生—埋藏期封闭局限海水渗透回流白云岩化;受到热液影响的该类型白云岩δ^(18)O_(VPDB)值为-7.33‰~-7.11‰,与泥晶灰岩相比略微偏负,^(87)Sr/^(86)Sr比值为0.707 950~0.708 171,高于同期海水。层状粉晶白云岩未明显受到热液影响改造,其成因与上述未受热液影响的层状细—中晶白云岩一致。而溶洞、裂缝中的鞍形白云石胶结物则是热液流体直接沉淀或重结晶所形成,具有较高的^(87)Sr/^(86)Sr比值(均值0.707 970)、明显偏负的δ^(18)O_(VPDB)值(均值-7.32‰)以及Eu的正异常。从层状粉晶白云岩、层状细—中晶白云岩到鞍形白云石胶结物,呈现出一种受控于封闭局限海水到热液流体的梯度性变化,研究区内的白云岩是由多期次流体、多次成岩作用的结果。 展开更多
关键词 地球化学特征 成因机理 白云岩 茅口组 中二叠统 四川盆地
下载PDF
大型钢结构多向钢节点电弧增材制造工艺
7
作者 汪阳 余圣甫 +2 位作者 权利 汪能 陈胜元 《焊接》 2024年第2期1-8,25,共9页
多向钢节点作为连接大型钢结构的关键构件,承载钢结构建筑各方向的力,对其安全性起至关重要的作用。基于七向钢节点结构特点,文中研究了电弧增材制造钢结构建筑的七向钢节点,采用分区成形、平曲面切片及摆动填充的路径规划方法,将其分... 多向钢节点作为连接大型钢结构的关键构件,承载钢结构建筑各方向的力,对其安全性起至关重要的作用。基于七向钢节点结构特点,文中研究了电弧增材制造钢结构建筑的七向钢节点,采用分区成形、平曲面切片及摆动填充的路径规划方法,将其分为直臂圆管区、相贯区和支管延长区3个区域,相贯区包括两管相贯、三管相贯和四管相贯3种类型。直臂圆管区和支管延长区采用摆动工艺进行堆积,两管相贯、三管相贯和四管相贯区分别采用曲面切片的路径规划进行堆积。对堆积完成的构件进行成形精度检测、微观组织的观测和力学性能的测量。结果表明,七向钢节点构件成形尺寸偏差为±1.32 mm,成形精度较高。微观组织为铁素体和珠光体,构件的抗拉强度和屈服强度相对于同成分铸件分别提高了约30%和105%,电弧增材制造的七向钢节点满足使用要求。 展开更多
关键词 七向钢节点 电弧增材制造 路径规划 成形精度
下载PDF
森林火灾风险下的配电线路单相断线放电发展过程研究
8
作者 权立 贺梦莎 +2 位作者 张小庆 王毅钊 付钰伟 《全球能源互联网》 CSCD 北大核心 2024年第1期55-65,共11页
随着台风、暴雪等极端恶劣环境的不断常态化,单相接地故障(如单相断线、单相击穿等)频繁发生,严重危害了电网安全。单相断线故障是引发森林火灾的常见故障之一,导线断线坠落至地面附近,在极短间隙内对地放电引燃地表附着的易燃物,最终... 随着台风、暴雪等极端恶劣环境的不断常态化,单相接地故障(如单相断线、单相击穿等)频繁发生,严重危害了电网安全。单相断线故障是引发森林火灾的常见故障之一,导线断线坠落至地面附近,在极短间隙内对地放电引燃地表附着的易燃物,最终引发森林火灾,对社会经济和自然环境危害严重。针对森林火灾风险下的配电线路单相断线对地放电发展过程研究建立短间隙放电模型,可以获得断口对地放电过程中的电场分布、电子平均能量分布、电子密度分布,以及不同断口外形对放电过程的影响机理。研究结果表明,随着断口半径从0.5 mm降至0.3 mm,流注头部的电场强度从80 kV/cm升高到110 kV/cm,电子平均能量从10 eV升高到11 eV,流注贯穿间隙时电子密度的最大值由1.5×10~(20)m~(-3)升高到2.7×10~(20) m~(-3)。断口半径越小、曲率越大,导致流注头部的电场强度和电子平均能量升高,流注头部电子密度和放电电流增加,更容易导致流注贯穿间隙。而断口不规则时由于具有更大半径,间隙击穿需要更长时间,因此放电电流峰值由9 A升高至15 A。如果考虑松针等含油量较高的地表附着物影响,该放电电流极易点燃地表附着物并形成电弧、引发火灾。该研究结果对于极端天气下的配电线路安全防护、预防森林火灾具有重要意义。 展开更多
关键词 山火放电机理 单相断线 流注放电
下载PDF
Ⅰ~Ⅲ期结直肠癌病人神经/脉管浸润风险因素分析并构建列线图预测模型
9
作者 权莉 张子晚 李莉 《安徽医药》 CAS 2024年第6期1203-1207,I0004,共6页
目的建立预测Ⅰ~Ⅲ期结直肠癌病人神经/脉管浸润(perineural or lymphovascular invasion,PNI/LVI)的列线图预测模型,验证和预测其效能。方法回顾性分析2017年1月至2022年9月徐州医科大学附属医院行结直肠癌根治术治疗的结直肠癌病人68... 目的建立预测Ⅰ~Ⅲ期结直肠癌病人神经/脉管浸润(perineural or lymphovascular invasion,PNI/LVI)的列线图预测模型,验证和预测其效能。方法回顾性分析2017年1月至2022年9月徐州医科大学附属医院行结直肠癌根治术治疗的结直肠癌病人684例的临床病理资料,利用R软件采用随机数种子的方式将上述资料按7∶3分成训练组(479例)和验证组(205例)。通过单因素相关分析,把P<0.1的参数纳入到多因素logistic回归分析,筛选影响结直肠恶性肿瘤PNI/LVI的危险因素,建立列线图模型。通过受试者操作特征曲线(ROC曲线)评估风险模型的预测价值,然后通过一致性指数、校准曲线和临床决策曲线分析(DCA)评估预测模型识别、校准和临床实用性方面的有效性。结果糖尿病、肿瘤长径、组织学分级、癌结节、T分期、N分期、血小板计数/淋巴细胞计数(PLR)、血小板计数×中性粒细胞计数/淋巴细胞(SII)、纤维蛋白原(g/L)/前白蛋白(g/L)(FPR)、癌胚抗原(CEA)、糖类抗原(CA)199在单因素分析中P<0.1。而多因素分析结果表明,CA199、T分期和N分期与Ⅰ~Ⅲ期结直肠癌病人PNI/LVI的发生独立相关因素。训练组和验证组的一致性指数分别为0.88[95%CI:(0.85,0.91)]和0.84[95%CI:(0.78,0.89)],同样校准曲线和DCA表明该模型具有良好的准确度和临床实用性。结论以CA199、T分期和N分期为基础建立的列线图模型有助于预测Ⅰ~Ⅲ期结直肠癌病人的PNI/LVI风险,该风险评价模型在临床上具有较好的预测效果。 展开更多
关键词 结直肠肿瘤 神经/脉管浸润 危险因素 预测模型 列线图
下载PDF
Experimental and clinical study of influence of high-frequency electric surgical knives on healing of abdominal incision 被引量:24
10
作者 Guang-Wei Ji Yuan-Zhi Wu +14 位作者 Xu Wang Hua-Xiong Pan Ping li Wan-Ying Du Zhi Qi An Huang li-Wei Zhang li Zhang Wen Chen Guang-Hua liu Hui Xu quan li Ai-Hua Yuan Xiao-Ping He Guo-Hua Mei 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第25期4082-4085,共4页
瞄准:在腹壁切口愈合上学习高周波的电的外科的刀的影响。方法:240 只白鼠被划分成 10 (0 ) , 10 (2 ) , 10 (5 ) ,并且 10 (8 ) 组和腹部手术的老鼠模型被分别地使用电的外科的刀和普通口针劝诱。然后,他们分别地被给生理盐水和 ... 瞄准:在腹壁切口愈合上学习高周波的电的外科的刀的影响。方法:240 只白鼠被划分成 10 (0 ) , 10 (2 ) , 10 (5 ) ,并且 10 (8 ) 组和腹部手术的老鼠模型被分别地使用电的外科的刀和普通口针劝诱。然后,他们分别地被给生理盐水和 0.2 mL 的皮下注射在 10 的集中(2 ) 的埃希氏杆菌属关口 i,葡萄球菌 aureus 和绿脓假单胞菌的量的混合, 10 (5 ) 并且 10 (8 ) 。根据动物实验,经历腹部手术(上面的类型 II ) 的 220 个病人随机被分配进跟随三个组之一:电热刀(EK, 93 个盒子) ,电凝法(EC, 55 个盒子) 并且控制(72 个盒子) 。高周波的电的外科的刀习惯于为在 EK 的血壅滞的腹的纸巾和电凝法组织的 dissect。普通口针和电凝法在 EC 组被使用。普通口针和系住的丝缝线在控制被使用。结果:在除了组 10 的所有组(0 ) ,电的外科的刀做的 incisional 创伤的感染率与普通口针比那显著地高。而且,在组有有效差量 10 (2 ) , 10 (5 ) ,并且 10 (8 )(P【0.05 ) ,然而并非(0 )(P】0.05 ) 在组, 10 在 EK 和 EC 之间组织。临床的研究显示出在控制组在 EK,在 EC 的 11 个盒子(16.36%) 和 2 个盒子(2.86%) 在 16 种情况(17.20%) 中愈合的一处推迟的创伤。在 EK 和控制之间的有效差量组织(chi2 = 8.57, P【0.01 ) ,并且在 EC 和控制组之间(chi2 = 5.66, P【0.05 ) 被观察,然而并非在 EK 和 EC 之间(chi2 = 0.017, P】0.05 ) 。结论:高周波的电的刀可以显著地推迟腹壁切口愈合。它的申请应该被最小化以便减少手术后的复杂并发症的可能性。 展开更多
关键词 实验研究 临床表现 高频手术刀 腹部手术
下载PDF
Adapter Based on Pre-Trained Language Models for Classification of Medical Text
11
作者 quan li 《Journal of Electronic Research and Application》 2024年第3期129-134,共6页
We present an approach to classify medical text at a sentence level automatically.Given the inherent complexity of medical text classification,we employ adapters based on pre-trained language models to extract informa... We present an approach to classify medical text at a sentence level automatically.Given the inherent complexity of medical text classification,we employ adapters based on pre-trained language models to extract information from medical text,facilitating more accurate classification while minimizing the number of trainable parameters.Extensive experiments conducted on various datasets demonstrate the effectiveness of our approach. 展开更多
关键词 Classification of medical text ADAPTER Pre-trained language model
下载PDF
Effects of rice or wheat residue retention on the quality of milled japonica rice in a rice–wheat rotation system in China 被引量:2
12
作者 Pengfu Hou Yanfeng Ding +6 位作者 Guofa Zhang quan li Shaohua Wang She Tang Zhenghui liu Chengqiang Ding Ganghua li 《The Crop Journal》 SCIE CAS CSCD 2015年第1期67-73,共7页
In rice–wheat rotation systems, crop straw is usually retained in the field at land preparation in every, or every other, season. We conducted a 3-year-6-season experiment in the middle–lower Yangtze River Valley to... In rice–wheat rotation systems, crop straw is usually retained in the field at land preparation in every, or every other, season. We conducted a 3-year-6-season experiment in the middle–lower Yangtze River Valley to compare the grain qualities of rice under straw retained after single or double seasons per year. Four treatments were designed as: both wheat and rice straw retained(WR), only rice straw retained(R), only wheat straw retained(W), and no straw retained(CK). The varieties were Yangmai 16 wheat and Wuyunjing 23 japonica rice. The results showed contrasting effects of W and R on rice quality. Amylopectin content, peak viscosity, cool viscosity, and breakdown viscosity of rice grain were significantly increased in W compared to the CK, whereas gelatinization temperature,setback viscosity, and protein content significantly decreased. In addition, the effect of WR on rice grain quality was similar to that of W, although soil fertility was enhanced in WR due to straw being retained in two cycles. The differences in protein and starch contents among the treatments might result from soil nitrogen supply. These results indicate that wheat straw retained in the field is more important for high rice quality than rice straw return, and straw from both seasons is recommended for positive effects on soil fertility. 展开更多
关键词 JAPONICA RICE Crop straw Grain QUALITY Paddy–upland rotation
下载PDF
Improved electrochemical performances of high voltage LiCoO_2 with tungsten doping 被引量:2
13
作者 张杰男 李庆浩 +2 位作者 李泉 禹习谦 李泓 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期605-611,共7页
The effects of tungsten W doping and coating on the electrochemical performance of LiCoO2 cathode are compara- tively studied in this work. The amount of modification component is as low as 0.1 wt% and 0.3 wt% respect... The effects of tungsten W doping and coating on the electrochemical performance of LiCoO2 cathode are compara- tively studied in this work. The amount of modification component is as low as 0.1 wt% and 0.3 wt% respectively. After 100 cycles between 3.0 V-4.6 V, 0.1 wt% W doping provides an optimized capacity retention of 72.3%. However, W coating deteriorates battery performance with capacity retention of 47.8%, even lower than bare LiCoO2 of 55.7%. These different electrochemical performances can be attributed to the surface aggregation of W between doping and coating methods. W substitution is proved to be a promising method to develop high voltage cathodes. Practical performance relies on detailed synthesis method. 展开更多
关键词 CATHODE lithium-ion batteries lithium cobalt oxide DOPING COATING
下载PDF
Nonlinear autopilot design for interceptors with tail fins and pulse thrusters via θ–D approach 被引量:3
14
作者 quan li Di Zhou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第2期273-280,共8页
The missile autopilot for an interceptor with tail fins and pulse thrusters is designed via the θ-D approach. The nonlin- ear dynamic model of the pitch and yaw motion of the missile is transformed into a linear-like... The missile autopilot for an interceptor with tail fins and pulse thrusters is designed via the θ-D approach. The nonlin- ear dynamic model of the pitch and yaw motion of the missile is transformed into a linear-like structure with state-dependent coef- ficient (SDC) matrices. Based on the linear-like structure, a θ-D feedback controller is designed to steer the missile to track refer- ence acceleration commands. A sufficient condition that ensures the asymptotic stability of the tracking system is given based on Lyapunov's theorem. Numerical results show that the proposed autopilot achieves good tracking performance and the closed-loop tracking system is asymptotically stable. 展开更多
关键词 blended control nonlinear control suboptimal control θ-D approach.
下载PDF
Artificial solid electrolyte interphase based on polyacrylonitrile for homogenous and dendrite-free deposition of lithium metal 被引量:1
15
作者 徐航宇 李泉 +4 位作者 潘弘毅 邱纪亮 曹文卓 禹习谦 李泓 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期523-528,共6页
High chemical reactivity, large volume changes, and uncontrollable lithium dendrite growth have always been the key problems of lithium metal anodes.Coating has been demonstrated as an effective strategy to protect th... High chemical reactivity, large volume changes, and uncontrollable lithium dendrite growth have always been the key problems of lithium metal anodes.Coating has been demonstrated as an effective strategy to protect the lithium metal.In this work, the effects of polyacrylonitrile(PAN)-based coatings on electrodeposited lithium have been studied.Our results show that a PAN coating layer provides uniform and dendrite-free lithium deposition as well as better cycling performance with carbonate electrolyte.Notably, heat treatment of the PAN coating layer promotes the formation of larger deposit particle size and higher coulombic efficiency(85%).The compact coating layer of heat-treated PAN with a large Young modulus(82.7 GPa) may provide stable protection for the active lithium.Improved homogeneity of morphology and mechanical properties of heat-treated PAN contribute to the larger deposit particles.This work provides new feasibility to optimize the polymer coating through rational modification of polymers. 展开更多
关键词 LITHIUM deposition polymer coating artificial solid ELECTROLYTE INTERPHASE POLYACRYLONITRILE
下载PDF
Arctigenin attenuates paraquat-induced human lung epithelial A549 cell injury by suppressing ROS/p38 mitogen-activated protein kinases-mediated apoptosis 被引量:1
16
作者 Chao liu Zhao-rui Sun +7 位作者 Meng-meng Wang Zhi-zhou Yang Wei Zhang Yi Ren Xiao-qin Han Rui liu quan li Shi-nan Nie 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2022年第5期373-378,共6页
BACKGROUND:Paraquat(PQ)-induced acute lung injury(ALI)and pulmonary fi brosis are common diseases with high mortality but without eff ective antidotes in emergency medicine.Our previous study has proved that arctigeni... BACKGROUND:Paraquat(PQ)-induced acute lung injury(ALI)and pulmonary fi brosis are common diseases with high mortality but without eff ective antidotes in emergency medicine.Our previous study has proved that arctigenin suppressed pulmonary fibrosis induced by PQ.We wondered whether arctigenin could also have a protective eff ect on PQ-induced ALI.METHODS:A PQ-induced A549 cell injury model was used,and the effect of arctigenin was determined by a cell counting kit-8(CCK-8)cell viability assay.In addition,terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick-end labelling(TUNEL)staining assays and mitochondrial membrane potential assays were performed to evaluate the level of cell apoptosis.The generation of reactive oxygen species(ROS)was refl ected by dihydroethidium(DHE)staining and a 2’,7’-dichlorodihy drofluorescein diacetate(DCFH-DA)assay.Moreover,immunoblotting studies were used to assess the expression of mitogen-activated protein kinases(MAPKs)and p38 MAPK.RESULTS:Arctigenin attenuated PQ-induced inhibition of A549 cell viability in a dose-dependent manner.Arctigenin also significantly reduced PQ-induced A549 cell apoptosis,as refl ected by the TUNEL assay and mitochondrial membrane potential assay,which may result from suppressed ROS/p38 MAPK signaling because we found that arctigenin dramatically suppressed ROS generation and p38 MAPK phosphorylation.CONCLUSION:Arctigenin could attenuate PQ-induced lung epithelial A549 cell injury in vitro by suppressing ROS/p38 MAPK-mediated cell apoptosis,and arctigenin might be considered a potential candidate drug for PQ-induced ALI. 展开更多
关键词 PARAQUAT A549 cells ARCTIGENIN Reactive oxygen species Mitogen-activated protein kinases Apoptosis
下载PDF
Taxonomic revision of the genus Mesechinus (Mammalia Erinaceidae) with description of a new species 被引量:1
17
作者 Huai-Sen Ai Kai He +7 位作者 Zhong-Zheng Chen Jia-Qi li Tao Wan quan li Wen-Hui Nie Jin-Huan Wang Wei-Ting Su Xue-Long Jiang 《Zoological Research》 SCIE CAS CSCD 2018年第5期335-347,共13页
Hedgehogs in the genus Mesechinus (Family Erinaceidae), which include two currently recognized species ( M. dauuricus and M. hughi), are distributed from northeast Mongolia to the upper Amur Basin in Russia and ad... Hedgehogs in the genus Mesechinus (Family Erinaceidae), which include two currently recognized species ( M. dauuricus and M. hughi), are distributed from northeast Mongolia to the upper Amur Basin in Russia and adjacent areas in northeast and northern China. In recent years, a population of Mesechinus hedgehogs was discovered from Mt. Gaoligong, southwestern Yunnan, China, far from the known distribution range of the genus. Furthermore, these hedgehogs are the only known population to be distributed at elevations higher than 2 100 m and in sympatry with gymnures. To evaluate the taxonomic status of these hedgehogs, we examined specimens representing Mesechinus taxa in China and further conducted morphometric and karyotypic analyses. Our results supported the existence of four species in China. Specifically, we identified the hedgehogs from Mt. Gaoligong as a new species, Mesechinus wangi sp. nov., and recognized M. miodon, previously considered as a synonym of either M. dauuricus or M. hughi as a distinct species. Interestingly, we observed a supernumerary M4 on all specimens of Mesechinus wangi sp. nov., which is an extremely rare event in the evolution of mammalian dentition. 展开更多
关键词 Mesechinus Taxonomy MorphometricsInhibitory cascade KARYOTYPE New speciesSupernumerary molar
下载PDF
定子励磁型混合磁路直线旋转永磁电机磁路设计与实验研究
18
作者 徐磊 朱孝勇 +4 位作者 刘路远 张超 刘浩 全力 CHEN Wenhua 《中国电机工程学报》 EI CSCD 北大核心 2023年第19期7683-7694,共12页
针对智能装备系统直线与旋转两自由度驱动需求,提出定子励磁型混合磁路直线旋转永磁(statorexcitedhybrid magnetic circuit linear and rotary permanent magnet,SEHMCLRPM)电机,采用轴向和径向双凸极齿结构,轴向直线运动与径向旋转运... 针对智能装备系统直线与旋转两自由度驱动需求,提出定子励磁型混合磁路直线旋转永磁(statorexcitedhybrid magnetic circuit linear and rotary permanent magnet,SEHMCLRPM)电机,采用轴向和径向双凸极齿结构,轴向直线运动与径向旋转运动磁场共用定、转子磁路。永磁体设置在定子上,动子上既无绕组也无永磁体,动子结构简单坚固,重量轻,具有转矩惯量比高、动态响应速度快、可靠性高等特点;定子同时设置有直线与旋转两套绕组,直线和旋转运动控制独立,降低两自由度驱动控制的复杂度。分析该类电机的运行原理和结构特点,探讨混合磁路特征,构建该类SEHMC-LRPM电机的解耦等效磁路模型,实现该类电机的磁路设计。在此基础上,基于3D有限元方法分析混合磁路与两自由度耦合磁场,揭示两自由度磁场与电机磁场分布、空载和负载特性的关系。最后,加工制造样机,并进行实验研究,验证该电机结构的有效性和理论分析的正确性。 展开更多
关键词 定子励磁 直线旋转 两自由度 永磁电机 混合磁路 磁路分析
下载PDF
Effects of platelet-rich plasma on in vitro proliferation and migration of fibroblasts from human chronic refractory wound granulation tissue 被引量:1
19
作者 Tie-ning Zhang quan li +3 位作者 Te Ba Tian-xi Shao Fang li ling-feng Wang 《Discussion of Clinical Cases》 2021年第1期24-28,共5页
Objective:To observe the effects of platelet-rich plasma(PRP)on in vitro proliferation and migration of fibroblasts from human chronic refractory wound granulation tissue.Methods:Fibroblasts were separated from human ... Objective:To observe the effects of platelet-rich plasma(PRP)on in vitro proliferation and migration of fibroblasts from human chronic refractory wound granulation tissue.Methods:Fibroblasts were separated from human chronic refractory wound granulation tissue and then were identified.The obtained fibroblasts were divided into fetal bovine serum(FBS)group,hydrogel group and PRP group,and the three groups were cultured with culture mediums containing FBS,hydrogel and PRP respectively,in order to observe the growth of fibroblasts.The wound scratch assay was used to observe the migration of fibroblasts.Results:PRP group had more fibroblasts than FBS group and hydrogel group since Day 5 of culture,and exhibited greater fibroblast scratch migration area than FBS group on 48 h and 72 h of wound scratch assay(all p<.05).Conclusions:Compared with FBS,human fibroblasts cultured by PRP can more effectively promote the proliferation and migration of fibroblasts. 展开更多
关键词 FIBROBLAST Chronic refractory wound Granulation tissue Platelet-rich plasma Cell proliferation Cell migration In vitro
下载PDF
Demonstration of quantum anti-Zeno effect with a single trapped ion
20
作者 张满超 吴伟 +4 位作者 何林泽 谢艺 吴春旺 黎全 陈平形 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期191-196,共6页
We experimentally demonstrate the quantum anti-Zeno effect in a two-level system based on a single trapped ion ^(40)Ca~+. In the large detuning regime, we show that the transfer from the ground state to the excited... We experimentally demonstrate the quantum anti-Zeno effect in a two-level system based on a single trapped ion ^(40)Ca~+. In the large detuning regime, we show that the transfer from the ground state to the excited state can be remarkably enhanced by the inserted projection measurements. The inserted measurements in our experiment are realized by the electron shelving technique. Compared to the ideal projection measurement, which makes the quantum state collapse instantaneously, a practical electron shelving process needs a finite time duration. The minimum time for this collapse process is shown to be inversely proportional to the square of the coupling strength between the measurement laser and the system. 展开更多
关键词 quantum anti-Zeno effect single trapped ion quantum measurement
下载PDF
上一页 1 2 11 下一页 到第
使用帮助 返回顶部