检索结果-南通市图书馆

Small molecular non-fullerene electron acceptors for P3HT-based bulk-heterojunction solar cells

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2014年第7期57卷 973-981页

作者： LIU Xin CAI Ping CHEN DongChen CHEN junwu SU ShiJian CAO Yong State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials & Devices South China University of Technology

Three small molecules with the same arms and different cores of perylene diimide(PDI)or indaceno[2,1-b:6,5-b']dithiophene(IDT)were designed and synthesized as the acceptor materials for P3HT-based bulk-heterojunction(BHJ)solar *** impacts of the different cores on the optical absorption,electrochemical properties,electron mobility,film morphology,photoluminescene characteristics,and solar cell performance were thoroughly *** three compounds possess a broad absorption covering the wavelength range of 400–700 nm and relatively low lowest unoccupied molecular orbital(LUMO)energy levels of?3.86,?3.81 and?3.99 *** highest power conversion efficiency of 0.82%was achieved for the BHJ solar cells based on SM3 as the acceptor material,the compound with a PDI core.

关键词： bulk-heterojunction solar cells electron acceptor non-fullerene n-type materials low band gap

注射成形低钨-钨连接度的90W-6Ni-4Mn的高比重合金及其组织与性能研究

在线全文

学校读者我要写书评

暂无评论

粉末冶金工业 2024年第3期34卷 21-27,33页

作者：伍威邓汲坤任伯勇刘君武仲洪海蒋阳合肥工业大学材料科学与工程学院安徽合肥230009

作为新一代动能穿甲弹材料,90W-Ni-Mn合金的制备一直存在W-W连接度高、烧结密度低以及加工成本过高等问题。为此,实验使用化学镀镍工艺对钨粉末进行处理,通过注射成形技术为喂料塑形,采用氩气-氩氢两步气氛烧结工艺制备出了低W-W连接度... 详细信息

作为新一代动能穿甲弹材料,90W-Ni-Mn合金的制备一直存在W-W连接度高、烧结密度低以及加工成本过高等问题。为此,实验使用化学镀镍工艺对钨粉末进行处理,通过注射成形技术为喂料塑形,采用氩气-氩氢两步气氛烧结工艺制备出了低W-W连接度的高密度90W-6Ni-4Mn合金。研究发现90W-6Ni-4Mn合金制品可以实现近净成形,且新型两步气氛烧结工艺既能还原W、Ni氧化物又能避免MnO的产生,制得的合金样品相对密度达99.2%,粘结相分布均匀,W-W连接度低。通过微观组织与断口形貌分析发现,化学镀镍能促进钨骨架的活化烧结提高合金致密度,同时还能使粘结相实现均匀分布。且具有低W-W连接度的90W-6Ni-4Mn合金由于W-W弱界面的减少,失效速率减缓,从而使其拥有1 583.4 MPa的抗压强度与968 MPa的抗拉强度,塑性与韧性可分别达到21.5%与5.3 J/cm^(2)。

关键词：低W-W连接度注射成形 90W-6Ni-4Mn合金微观组织力学性能

An improved method of absolute calibration to satellite altimeter: A case study in the Yellow Sea, China

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2014年第5期33卷 103-112页

作者： LIU Yalong TANG junwu ZHU Jianhua LIN Mingsen ZHAI Wanlin CHEN Chuntao Ocean University of China National Ocean Technological Center State Oceanic Administration National Satellite Ocean Application Service State Oceanic Administration

An improved absolute calibration technology based on indirect measurements was developed through two probative experiments, the performance of which was evaluated by applying the approach to in situ sea surface height （SSH） at the Tianheng Island （tidal gauge） and the satellite nadir （GPS buoy）. Using Geoid/MSS （mean sea surface） data, which accounted for a constant offset between nadir and onshore tidal gauge water levels, and TMD （tidal model driver）, which canceled out the time-varying offsets, nadir SSH （sea surface height） could be indirectly acquired at an onshore tidal gauge instead of from direct offshore observation. The approach extrapolated the onshore SSH out to the offshore nadir with an accuracy of （1.88±0.20） cm and a standard deviation of 3,3 cm, which suggested that the approach presented was feasible in absolute altimeter calibration/validation （Cal/Val）, and the approach enormously facilitated the obtaining SSH from the offshore nadir.

关键词： radar altimeter absolute calibration Yellow Sea

Near-fault ground motions with prominent acceleration pulses:pulse characteristics and ductility demand

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2007年第3期6卷 215-223页

作者： Mai Tong Vladimir Rzhevskyt Dai junwu George C Lee Qi Jincheng Qi Xiaozhai MCEER State University of New York at Buffalo USA Institute of Enginering Mechanics China Earthquake Administration Harbin 150080 China

Major earthquakes of last 15 years （e.g., Northridge 1994, Kobe 1995 and Chi-Chi 1999） have shown that many near-fault ground motions possess prominent acceleration pulses. Some of the prominent ground acceleration pulses are related to large ground velocity pulses, others are caused by mechanisms that are totally different from those causing the velocity pulses or fling steps. Various efforts to model acceleration pulses have been reported in the literature. In this paper, research results from a recent study of acceleration pulse prominent ground motions and an analysis of structural damage induced by acceleration pulses are summarized. The main results of the study include：（1） temporal characteristics of acceleration pulses; （2） ductility demand spectrum of simple acceleration pulses with respect to equivalent classes of dynamic systems and pulse characteristic parameters; and （3） estimation of fundamental period change under the excitation of strong acceleration pulses. By using the acceleration pulse induced linear acceleration spectrum and the ductility demand spectrum, a simple procedure has been developed to estimate the ductility demand and the fundamental period change of a reinforced concrete （RC） structure under the impact of a strong acceleration pulse.

关键词： near-fault ground motions acceleration pulse ductility demand spectrum

在线全文

学校读者我要写书评

暂无评论

复杂环境下深基坑全过程变形控制设计与实践

土工基础 2024年第3期38卷 419-426页

作者：廖志坚朱火根唐军武上海市地矿工程勘察(集团)有限公司上海200072 同济大学地下建筑与工程系上海200092

上海城区建筑物密集、管线众多、高架及隧道纵横交错,地下工程开发需求量大,市区深基坑工程施工难度越来越高,传统的基坑工程设计施工由强度控制,在复杂环境条件下需由变形控制。以上海市中心某宾馆深基坑工程为背景,介绍在复杂环境条件... 详细信息

上海城区建筑物密集、管线众多、高架及隧道纵横交错,地下工程开发需求量大,市区深基坑工程施工难度越来越高,传统的基坑工程设计施工由强度控制,在复杂环境条件下需由变形控制。以上海市中心某宾馆深基坑工程为背景,介绍在复杂环境条件下,运用勘察、设计和监测施工一体化的深基坑工程全过程变形控制思路。勘察阶段准确获取设计参数,设计阶段详细调查周边环境,采取有针对性的支护设计方法,施工阶段采用有效的降水方案和挖土措施,运用信息化监测手段,全过程控制基坑变形,保护周边环境。项目实施效果表明,采用全过程变形控制方法达到了预期目标,以期为类似深基坑的变形控制提供参考。

关键词：深基坑地下通道变形控制承压水基坑监测

An atlas of expression quantitative trait loci of microRNAs in longissimus muscle of eight-way crossbred pigs

在线全文

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2023年第6期50卷 398-409页

作者： Liepeng Zhong Min Zheng Yizhong Huang Tao Jiang Bin Yang Lusheng Huang junwu Ma State Key Laboratory for Pig Genetic Improvement and Production Technology Jiangxi Agricultural UniversityNanchangJiangxi 330045China

MicroRNAs(miRNAs)are key regulators of myocyte development and traits,yet insight into the genetic basis of variation in miRNA expression is still ***,we present a systematic analysis of expression quantitative trait loci(eQTL)for miRNA profiling in longissimus muscle of pigs from an eight-breed crossed heterogeneous *** integrating the whole-genome sequencing and miRNAomics data,we map 54 cis-and 292 trans-e QTLs at high resolution that are associated with the expression of 54 and 92miRNAs,***-three trans-acting loci are identified to affect the expression of nine myomi Rs(known muscle-specific miRNAs).MiRNAs in mammalian conserved miRNA clusters are found to be subjected to regulation by shared cis-e QTLs,while the expression of mature miRNA-5p/-3p counterparts is more likely to be regulated by different cis-e *** mapping and bioinformatics analyses pinpoint the peak cis-e SNP of mi R-4331-5p,rs344650810,which is located in its seed region,as a causal variant for the changes in expression and function of this ***,rs344650810 is significantly(P<0.01)correlated with the density and percentage of type I muscle ***,this study provides a comprehensive atlas of miRNA-e QTLs in porcine skeletal muscle and new insights into regulatory mechanisms of miRNA expression.

关键词： miRNA eQTL Pig Muscle Causal variant Regulatorymechanism

Long-tailed object detection of kitchen waste with class-instance balanced detector

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2023年第8期66卷 2361-2372页

作者： FANG LeYuan TANG Qi OUYANG LiHan YU junwu LIN JiaXing DING ShuaiYu TANG Lin College of Electrical and Information Engineering Hunan UniversityChangsha 410082China College of Environmental Science and Engineering Hunan UniversityChangsha 410082China

Intelligent detection and classification of kitchen waste can promote ecological sustainability by replacing inefficient manual ***,the presence of non-degradable waste mixed in kitchen waste often follows a long-tailed distribution,making it challenging to train convolutional neural network-based object detectors,which results in the unsatisfactory detection of tailclass *** address this challenge,we propose a class-instance balanced detector(CIB-Det) for intelligent detection and classification of kitchen ***-Det implements two strategies for the loss function:the class-balanced strategy(CBS)and the instance-balanced strategy(IBS).The CBS focuses more on tail classes,and the IBS concentrates on hard-to-classify instances adaptively during ***,CIB-Det comprehensively and adaptively addresses the long-tailed *** experiments on a real dataset of kitchen waste images support the effectiveness of CIB-Det for kitchen waste detection.

关键词： kitchen waste detection and classification object detection long-tailed distribution convolutional neural networks

威远311.1 mm井眼优快钻井技术的难点与对策

在线全文

学校读者我要写书评

暂无评论

化工管理 2024年第4期 90-92页

作者：常杨李永钊朱俊武李鹏娜中国石油集团长城钻探工程有限公司工程技术研究院辽宁盘锦124000

四川页岩气311.1 mm井眼压力体系复杂,层位多变化不定,部分地层可钻性差,钻进过程中存在滑动托压严重、机械钻速慢、井漏、气侵、卡钻事故频发等问题,严重影响了整体勘探开发。通过该井段的大数据分析,基于地质特点和易漏、卡钻等工程难... 详细信息

四川页岩气311.1 mm井眼压力体系复杂,层位多变化不定,部分地层可钻性差,钻进过程中存在滑动托压严重、机械钻速慢、井漏、气侵、卡钻事故频发等问题,严重影响了整体勘探开发。通过该井段的大数据分析,基于地质特点和易漏、卡钻等工程难点,从井下设备、井眼轨迹、钻井液性能调整和钻井参数设定等方面,提高机械钻速。但目前地面参数只是在客观陈述机械钻速变慢,钻头处实际获取的参数并未可知。利用井下钻压、转速和扭矩参数,结合机械钻速和水力参数表现整合成一个综合参数,规避井下作业风险的同时,真实评定井下工作状态,建立多元钻井参数实时优化系统,形成智能钻井服务能力,从而实现优快钻井技术。

关键词：钻压转速钻井技术

Design, synthesis and photovoltaic properties of a series of new acceptor-pended conjugated polymers

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2016年第12期59卷 1583-1592页

作者： Zhihong Wu Yongxiang Zhu Wei Li Yunping Huang junwu Chen Chunhui Duan Fei Huang Yong Cao Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of Technology

A series of novel acceptor-pended conjugated polymers featuring a newly developed carbazole-derived unit are designed and synthesized. The relationships between chemical structure and optoelectronic properties of the polymers are systematically in-vestigated. The control of UV-Vis absorption spectra and energy levels in resulting polymers are achieved by introducing suitable pended acceptor units. The photovoltaic properties of the resulting polymers are evaluated by blending the polymers with （6,6）-phenyl-CTFbutyric acid methyl ester. The resulting solar cells exhibit moderate performances with high open-circuit voltage. Charge transport properties and morphology were investigated to understand the performance of corresponding solar cells.

关键词： acceptor.pended conjugated polymers polymer solar cells band gap energy level