检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

某300MW机组高压进汽结构气动优化

汽轮机技术 2024年第1期66卷 7-8页

作者：刘志德刘云锋管伟诗魏红阳哈尔滨汽轮机厂有限责任公司哈尔滨150046 哈尔滨工业大学能源与科学工程学院哈尔滨150006

采用数值模拟的方法对某300MW汽轮机的高压进汽结构进行了气动优化,通过增大关键部位通流面积、增大过渡倒圆,降低了流速,总压损失由4.11%降低到0.045%,出口静压不均匀度由0.67降低到0.020。

关键词：汽轮机高压进汽气动优化

电力自动化专业各研究领域发展趋势与现状调查

在线全文

学校读者我要写书评

暂无评论

长沙电力学院学报（自然科学版） 2006年第4期21卷 134-139页

作者：陈纲曹斌勇刘宏伟长沙理工大学湖南长沙410076

以电力自动化专业内的各研究领域和方法为对象,以相关主题的学术论文发表数量为标准,评估专业内各领域研究活动活跃程度及各研究方法的发展走向,并试图从中找出一定的规律,为从事该专业领域研究的科研人员提供一个选题依据.

关键词：电力系统自动化专业拟合网络数据库

在线全文

学校读者我要写书评

暂无评论

小型铅芯橡胶支座剪切性能试验研究

振动工程学报 2024年第2期37卷 326-335页

作者：韩淼刘祥辉杜红凯蒋金卫杨杰川北京建筑大学土木与交通工程学院北京100044

通过对小型铅芯橡胶支座(LRB)进行剪切试验,研究了支座剪应变、压应力和加载频率对支座等效水平刚度、屈服后刚度、屈服力和等效阻尼比的影响。结果表明:随着剪应变的增大,支座的等效水平刚度和屈服后刚度减小,屈服力增大,等效阻尼比呈... 详细信息

通过对小型铅芯橡胶支座(LRB)进行剪切试验,研究了支座剪应变、压应力和加载频率对支座等效水平刚度、屈服后刚度、屈服力和等效阻尼比的影响。结果表明:随着剪应变的增大,支座的等效水平刚度和屈服后刚度减小,屈服力增大,等效阻尼比呈线性减小;随着竖向压应力的增大,支座的等效水平刚度减小,屈服后刚度呈线性减小,屈服力和等效阻尼比呈线性增大;加载频率对支座的剪切性能基本没有影响,可以忽略;100%剪应变以内,施加的剪应变和压应力没有对隔震支座造成损伤;剪应变超过100%的大变形和大压应力会使支座进入塑性,造成支座部分永久性损伤。建议根据振动台试验的工况顺序及支座在振动台试验的最大实际变形设计拟静力试验的工况。提出日本规范等效水平刚度计算公式的修正系数,并与振动台试验实测值进行对照,证明了修正后的计算公式计算精度有所提高。

关键词：小型铅芯橡胶支座剪应变压应力加载频率振动台试验

A new nonfullerene acceptor with an extended π conjugation core enables ternary organic solar cells approaching 19%efficiency

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第5期17卷 4062-4068页

作者： Chunyan liu Nailiang Qiu Zhengjin Li Yan Lu School of Materials Science and Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials and Photoelectric DevicesMinistry of EducationTianjin University of TechnologyTianjin 300384China School of Chemistry Chemical Engineering and MaterialsJining UniversityQufu 273155China

In organic solar cells(OSCs),it is an effective way to improve the power conversion efficiency(PCE)by adding a guest component with appropriate absorption and energy levels in the host ***,a new nonfullerene acceptor(NFA)named TBF-2Cl was developed by the strategy of expanding theπconjugated core of 2,2’-(((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b’]dithiophene-2,7-diyl)bis(methaneylylidene))bis(5,6-dichloro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(IDT-4Cl)with two benzene *** increase of benzene units,TBF-2Cl exhibits higher lowest unoccupied molecular orbital(LUMO)level of-3.75 eV than that of one benzene unit based NFA IDT-4Cl and fluorene core based NFA F-2Cl,which facilitates enhancing the open-circuit voltage(V_(oc))of ternary ***,TBF-2Cl film shows a medium optical bandgap with the absorption range from 500-800 nm,being well complementary with the wide bandgap polymer donor D18 and narrow bandgap NFA ***,a remarkable PCE of 18.92%with a high short-circuit current density(J_(sc))of 27.40 mA·cm^(-2),a fill factor(FF)of 0.749,especially an outstanding V_(oc) of 0.922 V was achieved for the optimal ternary device based on D18:TBF-2Cl:CH-6F,surpassing the binary counterpart(17.08%).The findings provide insight into the development of new guest acceptors for obtaining more efficient OSCs.

关键词： medium optical bandgap high lowest unoccupied molecular orbital(LUMO)level the third component ternary organic solar cell high open-circuit voltage

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

高程导线测量竞赛对策研究

现代测绘 2023年第5期46卷 57-61页

作者：姚先锋王宏俊刘伟宏江苏省测绘地理信息职业技能鉴定指导中心江苏南京210013 江苏工程职业技术学院江苏南通226005

高程导线测量在地面起伏较大、视线较长的地区有着广泛的应用,只要作业过程严谨细致,高程导线可以代替高等级水准控制测量。高程导线测量作为竞赛项目可以比较全面地考核参赛队伍使用全站仪进行平面控制、高程控制的测量与计算技能。参... 详细信息

高程导线测量在地面起伏较大、视线较长的地区有着广泛的应用,只要作业过程严谨细致,高程导线可以代替高等级水准控制测量。高程导线测量作为竞赛项目可以比较全面地考核参赛队伍使用全站仪进行平面控制、高程控制的测量与计算技能。参照江苏省住房与城乡建设系统2021年工程测量员职业技能大赛竞赛细则和《城市测量规范》(CJJT8-2011),分析了高程导线的原理和技术要求,通过多次测量比对,找出了高程导线测量往返测高差较差超限的原因,论述了高程导线测量若要取得合格成果必须进行仪器高修正,给出了仪器高修正值测定方法,最后结合组织“工程测量员”技能大赛备赛的经验,阐述了竞赛制胜的对策建议。

关键词：高程导线仪器高修正竞赛对策

Small amount but big impact:Trace oxygen interstitially inserted PtCu alloys by microalloying for efficient oxygen reduction catalysis

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 7001-7012页

作者： Qiheng Wang Zhiguo Chen Jingyan Zhang Jingjun liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

The introduction of small size non-metal elements(e.g.,oxygen)into solid solution alloys may be a promising strategy for fabricating efficient Pt-based catalysts with high activity and stability toward oxygen reduction reaction(ORR).Herein,oxygen interstitially inserted PtCu(O-PtCu)alloys are firstly designed by an oxygen-microalloying strategy,through ultraviolet(UV)irradiation-assisted galvanic replacement in an aqueous solution containing H_(2)PtCl_(6) and Cu_(2)O nanowires as sacrificial *** obtained O-PtCu alloys feature a typical face-centered cubic(FCC)structure with majority Pt,Cu atoms as building bricks and trace interstitial oxygen(1.65 wt.%)existed in the octahedral sites surrounding Cu atoms,leading to a short-range disordered *** alloy reaches a recorded half-wave potential of 0.96 V(*** hydrogen electrode(RHE))and mass activity of 0.48 A·mgPt^(−1),much higher than those of commercial Pt/*** the accelerated degradation test(ADT),the mass activity lost only 4.2%after 10k cycles,while the commercial Pt/C lost 66.7%under the same *** with pure Pt and undoped PtCu alloy,the remarkably improved performance can be attributed to the lattice distortion and energy band reconstruction caused by the interstitial oxygen atoms in form of Cu–O ***,the stable Cu–O bonds delay the possible place exchange between surface Pt atoms and surface-adsorbed oxygen species,thereby hindering Pt dissolution,providing a new paradigm to address Pt degradation ***,the introduction of interstitial oxygen into Pt-based alloys may be a facile and smart strategy for the development of advanced Pt-based alloys electrocatalysts.

关键词： oxygen-microalloying platinum alloys octahedral interstices oxygen reduction reaction

From molecule to cell:the expanding frontiers of plant immunity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2024年第7期51卷 680-690页

作者： Lei Li Jing liu Jian-Min Zhou Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Hainan Yazhou Bay Seed Laboratory SanyaHainan 572025China

In recent years,the field of plant immunity has witnessed remarkable *** the co-evolution between plants and pathogens,plants have developed a wealth of intricate defense mechanisms to safeguard their *** identified immune receptors have added unexpected complexity to the surface and intracellular sensor networks,enriching our understanding of the ongoing plant–pathogen *** the molecular mechanisms of resistosome shapes our understanding of these mysterious molecules in plant ***,technological innovations are expanding the horizon of the plant–pathogen battlefield into spatial and temporal *** the development provides new opportunities for untangling the complex realm of plant immunity,challenges remain in uncovering plant immunity across spatiotemporal dimensions from both molecular and cellular levels.

关键词： Plant immunity Calcium Spatiotemporal Biomolecular condensate Immune receptor Resistosome

Satellite anomaly detection based on reconstruction discrepancy theory utilizing a new dual-branch reconstruction model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Technological Sciences 2024年第10期67卷 3294-3307页

作者： ZHAO HaoTian QIU Shi liu Ming CAO XiBin Research Center of Satellite Technology School of AstronauticsHarbin Institute of Technology

To enhance the accuracy of deep learning methods based on reconstruction discrepancy in satellite anomaly detection tasks, this study proposes a dual-branch reconstruction model(DBRM) and designs a comprehensive satellite anomaly detection framework around this model. Firstly, we introduce the temporal-channel mixer(TC-Mixer) module, which mainly comprises a self-attention layer for capturing long-range temporal dependencies in telemetry data, and two types of feed-forward networks(FFN) for extracting complex patterns in the temporal and channel dimension of telemetry data. This design endows the TC-Mixer module with robust capabilities for extracting complicated dependencies in telemetry data. Secondly, with the TC-Mixer module as the main component, we designed the DBRM. This model utilizes a shared latent representation layer, allowing the regeneration branch and forecasting branch of the DBRM to share most of the feature extraction network architecture. This approach significantly enhances the model's regression accuracy while reducing computational complexity. Thirdly, using the DBRM as the core network model, we devised a comprehensive satellite anomaly detection framework. This includes an anomaly criterion that considers the reconstruction discrepancy of both the regeneration and forecasting branches, the peak-over-threshold(POT) method for anomaly thresholding, and the MIC-based feature engineering method, etc. Finally, we conducted comparative experiments with several SOTA anomaly detection algorithms on two public and one private satellite anomaly detection datasets. The experimental results validate the effectiveness and superiority of our proposed method.

关键词： anomaly detection reconstruction discrepancy dual-branch reconstruction model (DBRM) satellite telemetry data time series

Comparison of different preoperative objective nutritional indices for evaluating 30-d mortality and complications after liver transplantation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Surgery 2024年第1期16卷 143-154页

作者： Chuan Li hong-Xia Chen Yan-Hua Lai Department of Transplantation People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Clinical Pharmacy People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND The nutritional status is closely related to the prognosis of liver transplant re-cipients,but few studies have reported the role of preoperative objective nutri-tional indices in predicting liver transplant *** To compare the predictive value of various preoperative objective nutritional indicators for determining 30-d mortality and complications following liver transplantation(LT).METHODS A retrospective analysis was conducted on 162 recipients who underwent LT at our institution from December 2019 to June *** This study identified several independent risk factors associated with 30-d mor-tality,including blood loss,the prognostic nutritional index(PNI),the nutritional risk index(NRI),and the control nutritional *** 30-d mortality rate was 8.6%.Blood loss,the NRI,and the PNI were found to be independent risk factors for the occurrence of severe postoperative *** NRI achieved the highest prediction values for 30-d mortality[area under the curve(AUC)=0.861,P<0.001]and severe complications(AUC=0.643,P=0.011).Compared to those in the high NRI group,the low patients in the NRI group had lower preoperative body mass index and prealbumin and albumin levels,as well as higher alanine aminotransferase and total bilirubin levels,Model for End-stage Liver Disease scores and prothrombin time(P<0.05).Furthermore,the group with a low NRI exhibited significantly greater incidences of intraabdominal bleeding,primary graft nonfunction,and *** The NRI has good predictive value for 30-d mortality and severe complications following *** NRI could be an effective tool for transplant surgeons to evaluate perioperative nutritional risk and develop relevant nutritional therapy.

关键词： Liver transplantation Nutritional indicator Complications Prognosis Nutrition assessment