检索结果-南通市图书馆

A comparative study on mechanical and vibroacoustic performance of sandwich cylindrical shells with positive,negative,and zero Poisson’s ratio cellular cores

引用

Journal of Ocean Engineering and Science 2024年第4期9卷 379-390页

作者： qing li Peichang li Yongjin Guo Xi’an liu State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China China Ship Development and Design Center Wuhan430064China MOE Key Laboratory of Marine Intelligent Equipment and System Shanghai Jiao Tong UniversityShanghai200240China

Deep-sea submersibles are significant mobile platforms requiring multi-functional capabilities that are strongly determined by the constituent *** cylindrical protective cover can be advanced by designing their sandwiched cellular materials whose physical properties can be readily parameterized and flexibly *** honeycomb materials are capable of possessing tuned positive,negative,or zero Poisson’s ratios(PPR,NPR,and ZPR),which is expected to produce distinct physical performance when utilized as a cellular core of cylindrical shells for the deep-sea submersibles.A novel cylindrical meta-structure sandwiched with the semi-re-entrant ZPR metamaterial has been designed as well as its similarly-shaped sandwich cylindrical shell structures with PPR and NPR *** mechanical and vibroacoustic performance of sandwich cylindrical shells with cellular materials featuring a full characteristic range of Poisson’s ratios are then compared systematically to explore their potential for engineering applications on submerged pressure-resistant *** respective unit cells are designed to feature an equivalent load-bearing *** properties of pressure resistance,buckling,and sound insulation are simulated,respectively,and the orders of each property are then generalized by systematic *** results indicate that the PPR honeycomb core takes advantage of higher structural strength and stability while the ZPR one yields better energy absorption and sound insulation *** NPR one yields moderate properties and has the potential for lower circumferential *** work explores the application of cellular materials with varied Poisson’s ratios and provides guidance for the multi-functional design of sandwich cylindrical meta-structures.

关键词： Sandwich cylindrical shells Poisson’s ratio Pressure-resistant Buckling Vibroacoustic

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phosphorylated cellulose nanofibers establishing reliable ion-sieving barriers for durable lithium-sulfur batteries

引用

Journal of Energy Chemistry 2024年第5期92卷 619-628页

作者： Zihao li Pengsen Qian Hongyang li He Xiao jun Chen Gaoran li School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina National Forestry and Grassland Administration Key Laboratory of Plant Fiber Functional Materials Fuzhou 350108FujianChina

The shuttle effect is among the most characteristic and formidable challenges in the pursuit of high-performance lithium-sulfur(li-S)***,phosphorylated cellulose nanofibers(pCNF)are intentionally engineered to establish an ion-sieving barrier against polysulfide shuttling and thereby improve battery *** phosphorylation,involving the grafting of phosphate groups onto the cellulose backbone,imparts an exceptional electronegativity that repels the polysulfide anions from penetrating through the ***,the electrolyte wettability and li^(+)transfer can be significantly promoted by the polar nature of pCNF and the facile li^(+)*** such,rational ion management is realized,contributing to enhanced reversibility in both sulfur and lithium *** a result,li-S cells equipped with the self-standing pCNF separator demonstrate outstanding long-term cyclability with a minimum fading rate of 0.013%per cycle over 1000 cycles at 1 C,and a decent areal capacity of 5.37 mA h cm^(-2) even under elevated sulfur loading of 5.0 mg cm^(-2) and limited electrolyte of 6.0 mL g^(-1).This work provides a facile and effective pathway toward the well-tamed shuttle effect and highly durable li-S batteries.

关键词： lithium-sulfur batteries Cellulose Phosphorylation Ion-sieving Shuttle effect

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Time-domain dynamic constitutive model suitable for mucky soil site seismic response

引用

Earthquake Engineering and Engineering Vibration 2024年第1期23卷 1-13页

作者： Dong qing Chen Su Jin liguo Zhou Zhenghua li Xiaojun Architectural Engineering Institute Huaiyin Institute of TechnologyHuai’an 223600China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100020China Institute of Geophysics China Earthquake AdministrationBeijing 100089China College of Transportation Science and Engineering Nanjing Tech UniversityNanjing 211816China

Soil nonlinear behavior displays noticeable effects on the site seismic *** study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton *** integrating shear modulus and combining the dynamic skeleton curve and the damping degradation coefficient,the constitutive equation of the logarithmic dynamic skeleton can be obtained,which considers the damping effect in a soil dynamics *** on the finite difference method and the multi-transmitting boundary condition,a 1D site seismic response analysis program called Soilresp1D has been developed herein and used to analyze the time-domain seismic response in three types of *** the same time,this study also provides numerical simulation results based on the hyperbolic constitutive model and the equivalent linear *** results verify the rationality of the new soil dynamic constitutive *** can analyze the mucky soil site nonlinear seismic response,reflecting the deformation characteristics and damping effect of the silty *** hysteresis loop area is more extensive,and the residual strain is evident.

关键词： seismic response time-domain dynamic constitutive model logarithmic dynamic skeleton dampening effect mucky soil

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

汽轮发电机负荷变化时水内冷定子线棒的温度水力模型

引用

中国电机工程学报 2005年第9期25卷 122-125页

作者：李俊卿李和明华北电力大学电气工程学院河北省保定市071003

大型汽轮发电机水内冷定子绕组的出水口温度以及定子槽内上下层线棒之间的温度监测是发电机状态监测和早期故障诊断中的一个重要方面,对发电机的安全、经济运行具有重要作用。为此,根据传热学和流体力学的基本原理,提出了汽轮发电机负... 详细信息

大型汽轮发电机水内冷定子绕组的出水口温度以及定子槽内上下层线棒之间的温度监测是发电机状态监测和早期故障诊断中的一个重要方面,对发电机的安全、经济运行具有重要作用。为此,根据传热学和流体力学的基本原理,提出了汽轮发电机负荷变化时水内冷定子线棒的温度水力模型,采用热平衡方程将温度模型离散化为非线性方程组,联立求解定子绕组温度与冷却水温度的方程组,即可求出定子线棒中的温度分布。根据线棒内三维温度分布的计算结果,提出了状态监测中定子线棒内铜温和水温标准值的确定方法。最后计算了一台QFSN-220-2 型汽轮发电机的一根定子线棒内的温度分布,结果表明该模型以及计算方法是正确的。

关键词：定子线棒水力模型负荷变化水内冷大型汽轮发电机非线性方程组温度分布状态监测热平衡方程冷却水温度故障诊断温度监测定子绕组经济运行基本原理流体力学温度模型绕组温度计算结果计算方法定子槽出水口

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

汽轮发电机状态监测中定子温度标准值的确定

引用

中国电机工程学报 2007年第9期27卷 87-91页

作者：李俊卿李和明华北电力大学电气工程学院河北省保定市071003

为了便于运行人员实时监测发电机定子各部位的温度,需要确定发电机在各种运行状态下的温度标准值。为此,研究了基于发电机定子三维温度场的温度标准值的确定方法。根据传热学和流体力学的基本原理,提出了汽轮发电机定子三维温度场的数... 详细信息

为了便于运行人员实时监测发电机定子各部位的温度,需要确定发电机在各种运行状态下的温度标准值。为此,研究了基于发电机定子三维温度场的温度标准值的确定方法。根据传热学和流体力学的基本原理,提出了汽轮发电机定子三维温度场的数学模型,模型中考虑了温度场与流体场的耦合。采用热平衡原理对定子温度场的偏微分方程进行离散化处理,与冷却介质温度的计算相耦合,形成联立方程组。求解联立方程组即可求出定子的三维温度分布,从而确定发电机定子任一部位温度的标准值。计算了一台QFSN-220-2型汽轮发电机在不同运行工况下定子的三维温度场,与实测值比较,结果表明该模型以及计算方法是正确的。

关键词：汽轮发电机定子温度场温度标准值状态监测

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

计及转子静偏心的双馈式发电机转子匝间短路故障频谱特性的仿真分析

引用

电机与控制学报 2015年第6期19卷 1-5页

作者：李俊卿张立鹏华北电力大学电气与电子工程学院河北保定071003

为了研究双馈风力发电机转子静偏心故障和转子绕组匝间短路故障频谱特性的区别,避免静偏心导致对转子绕组匝间短路故障的误诊断。依据有限元理论,建立双馈风力发电机转子绕组匝间短路模型和计及静偏心的模型,对转子绕组匝间短路、计及... 详细信息

为了研究双馈风力发电机转子静偏心故障和转子绕组匝间短路故障频谱特性的区别,避免静偏心导致对转子绕组匝间短路故障的误诊断。依据有限元理论,建立双馈风力发电机转子绕组匝间短路模型和计及静偏心的模型,对转子绕组匝间短路、计及静偏心的转子匝间短路故障进行了仿真。以转子线电流和定子线电压为研究对象,从频谱特性角度,对各组的仿真结果进行了对比研究。分析结果表明,静偏心的存在会导致定子线电压中出现与转子绕组匝间短路故障相同的特征频率,可能导致误诊断;同时对转子线电流和定子线电压以及定子线电压的高频段进行监测,能够有效区分静偏心与转子绕组匝间短路故障,避免静偏心导致对转子绕组匝间短路故障的误诊断。

关键词：双馈式发电机有限元转子匝间短路转子静偏心频谱特征区分

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

SLC6A14 promotes ulcerative colitis progression by facilitating NLRP3 inflammasome-mediated pyroptosis

引用

World Journal of Gastroenterology 2024年第3期30卷 252-267页

作者： qing Gu Huan Xia Yue-Qiong Song jun Duan Yun Chen You Zhang He-Ping Chen li Zhang Department of Elderly Digestive Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalUniversity of Electronic Science and TechnologyChengdu 610072Sichuan ProvinceChina Geriatrics Research Institute Sichuan Provincial People’s HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Ulcerative colitis(UC)is an inflammatory condition with frequent relapse and *** suggests the involvement of SLC6A14 in UC pathogenesis,but the central regulator remains *** To explore the role of SLC6A14 in UC-associated *** Quantitative real-time polymerase chain reaction(qRT-PCR),immunoblotting,and immunohistochemical were used to assess SLC6A14 in human UC ***(LPS)was used to induce inflammation in FHC and NCM460 cells and model enteritis,and SLC6A14 levels were *** markers were quantified using enzyme-linked immunosorbent assay,Western blotting,and qRT-PCR,and EdU incubation,CCK-8 assays and flow cytometry were used to examine proliferation and *** models of UC were used for *** SLC6A14 was increased and correlated with NLRP3 in UC ***-induced FHC and NCM460 cells showed increased SLC6A14 *** SLC6A14 increased cell proliferation and suppressed *** SLC6A14 decreased pyroptosis-associated proteins(ASC,IL-1β,IL-18,NLRP3).NLRP3 overexpression counteracted the effects of sh-SLC6A14 on LPS-induced FHC and NCM460 cell ***6A14 improved the mucosa in mice with dextran sulfate sodium-induced *** SLC6A14 promotes UC pyroptosis by regulating NLRP3,suggesting the therapeutic potential of modulating the SLC6A14/NLRP3 axis.

关键词： Ulcerative colitis SLC6A1 NLRP3 Pyroptosis Inflammasome

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

HHO optimized support vector machine classifier for traditional Chinese medicine syndrome differentiation of diabetic retinopathy

引用

International Journal of Ophthalmology(English edition) 2024年第6期17卷 991-1000页

作者： li Xiao Cheng-Wu Wang Ying Deng Yi-Jing Yang Jing Lu jun-Feng Yan qing-Hua Peng School of Chinese Medicine Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina School of Informatics Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Provincial Key Laboratory for Prevention and Treatment of Ophthalmology and Otolaryngology Diseases with Chinese Medicine Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Provincial Engineering and Technological Research Center for Prevention and Treatment of Ophthalmology and Otolaryngology Diseases with Chinese Medicine and Protecting Visual Function Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina

AIM:To develop a classifier for traditional Chinese medicine(TCM)syndrome differentiation of diabetic retinopathy(DR),using optimized machine learning algorithms,which can provide the basis for TCM objective and intelligent syndrome ***:Collated data on real-world DR cases were collected.A variety of machine learning methods were used to construct TCM syndrome classification model,and the best performance was selected as the basic *** Algorithm(GA)was used for feature selection to obtain the optimal feature *** Hawk Optimization(HHO)was used for parameter optimization,and a classification model based on feature selection and parameter optimization was *** performance of the model was compared with other optimization *** models were evaluated with accuracy,precision,recall,and F1 score as ***:Data on 970 cases that met screening requirements were *** Vector Machine(SVM)was the best basic classification *** accuracy rate of the model was 82.05%,the precision rate was 82.34%,the recall rate was 81.81%,and the F1 value was 81.76%.After GA screening,the optimal feature combination contained 37 feature values,which was consistent with TCM clinical *** model based on optimal combination and SVM(GA_SVM)had an accuracy improvement of 1.92%compared to the basic *** model based on HHO and GA optimization(HHO_GA_SVM)had the best performance and convergence speed compared with other optimization *** with the basic classification model,the accuracy was improved by 3.51%.CONCLUSION:HHO and GA optimization can improve the model performance of SVM in TCM syndrome differentiation of *** provides a new method and research idea for TCM intelligent assisted syndrome differentiation.

关键词： traditional Chinese medicine diabetic retinopathy Harris Hawk Optimization Support Vector Machine syndrome differentiation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Dt1-SWEET10a partner:Photoperiodic control of seed weight in soybean

引用

Molecular Plant 2024年第6期17卷 839-841页

作者： li-qing Chen Lalit Dev Tiwari Department of Plant Biology University of Illinois at Urbana-ChampaignUrbanaIL 61801USA DOE Center for Advanced Bioenergy and Bioproducts Innovation University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Institute for Sustainability Energyand EnvironmentUniversity of Illinois at Urbana-ChampaignUrbanaIL 61801USA

Seed weight and size are critical agronomic traits essential for determining yield and composition,receiving significant attention throughout domestication(Meyer et al.,2012).Seed weight serves as a reliable indicator of average seed size due to their positive *** of seed weight involves both developmental and environmental cues,affecting cell proliferation or expansion(li et al.,2019).

关键词： soybean SWEET1 weight

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Experimental research on the launching system of auxiliary charge with filter cartridge structure

引用

Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-jun Chen Ze He Hong-Hao Ma Lu-qing Wang Zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the *** combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the *** breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the *** this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the *** proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the *** order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are *** experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak *** projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,*** muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the *** the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：