检索结果-南通市图书馆

nSiO2-PVDF复合膜制备与膜蒸馏性能研究

在线全文

学校读者我要写书评

暂无评论

水处理技术 2025年第03期51卷 67-71页

作者：侯雪怡黄世耿班锦宏卢彦越广西民族大学化学化工学院广西高校化学与生物转化过程新技术重点实验室

为了提高聚偏氟乙烯（PVDF）平板膜的膜蒸馏分离性能，用溶胶凝胶法制备不同粒径的纳米二氧化硅（nSiO2）溶胶作为致孔剂，采用相转换方法制备nSiO2-PVDF复合膜。利用XRD、XPS、SEM等对PVDF膜和nSiO2-PVDF复合膜进行表征，研究了纳米nS... 详细信息

为了提高聚偏氟乙烯（PVDF）平板膜的膜蒸馏分离性能，用溶胶凝胶法制备不同粒径的纳米二氧化硅（nSiO2）溶胶作为致孔剂，采用相转换方法制备nSiO2-PVDF复合膜。利用XRD、XPS、SEM等对PVDF膜和nSiO2-PVDF复合膜进行表征，研究了纳米nSiO2的粒径和添加量对复合膜形貌和结构、疏水性能以及膜蒸馏分离性能的影响。分析结果表明，在添加不同粒径的纳米nSiO2溶胶后，复合膜的水通量大幅提升。在进料液为质量分数3.5%Na Cl溶液，进料温度为75℃，渗透测温度为25℃的条件下，添加质量分数3%的100 nm nSiO2的复合膜水通量达到22.1 kg/（m2·h），相对于未改性膜提高了116.7%；其截留率高达99.9%以上。

关键词：直接接触膜蒸馏海水淡化聚偏氟乙烯膜纳米二氧化硅

Emergency Logistics Management for hazardous Materials with Demand Uncertainty and Link Unavailability

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2023年第2期32卷 175-205页

作者： Ginger y.Ke James h.Bookbinder Faculty of Business Administration Memorial University of NewfoundlandSt.John’sNewfoundland and LabradorA1B 3X5Canada Department of Management Sciences University of WaterlooWaterlooOntarioN2L 3G1Canada

Due to its harmful nature,any incident associated with hazardous material(hazmat)may cause tremendous impacts on the surrounding people and the *** on the incident involving this specific type of good,we develop a reliable and robust emergency logistics network that considers both demand uncertainty and possible unavailability of particular links.A time-based risk measure is carefully designed upon the traditional risk assessment to reflect the stakeholder’s sensitivity to risk over response *** disruption and uncertainty are modeled as two sets of scenarios which are integrated into a bi-objective robust model to evaluate the trade-offs between risk and *** effectiveness of the emergency response can be assured by expenditures that add extra capacities to certain links or establish additional facilities that aid recovery from *** apply our model and approach to a real-world network in Guangdong *** results reveal the necessity of embedding consideration of uncertainty and unreliability into emergency network design problems;outline the importance of hedging against unpredictability by system redundancies;and indicate the impact of stakeholder’s orientation towards cost and risk on the location,allocation,and routing decisions in hazmat emergency response.

关键词： Emergency response hazardous materials robust optimization link disruption emergency demand uncertainty

Effect of samarium oxide on structural,optical and electrical properties of some alumino-borate glasses with constant copper chloride

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

Journal of Rare Earths 2020年第7期38卷 770-775,I0004页

作者： M.S.Sadeq h.y.Morshidy Basic Sciences Dept. Faculty of EngineeringSinai Univ.45511Al-ArishEgypt

The glass system under study was prepared and examined using the melt quenching procedures and XRD to emphasize the amorphous nature,*** of the prepared solid glass system was performed by a spectrophotometer in wavelengths from 190 to 1099 *** traditional techniques and standard formulas,the density,molar volume,refractive index,optical band gap and the optical filter characteristics were determined,then the influence of samarium oxide on some properties like the structure and optical,also the electrical properties were dissected.A novel formula was proposed to estimate the refractive index from the optical energy *** obtained samples are good optical filters especially the sample that contains 0.8 mol% of Sm2 *** this sample has the utmost density,the least molar volume,the maximum transmittance,least refractive index,the highest optical band gap and the least dc conductivity.

关键词： Alumino borate glasses Samarium oxide Optical properties Rare earths

Composition and size dependent torsion fracture of metallic glasses

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第23期82卷 153-160页

作者： J.Dong J.Shen y.h.Sun h.B.Ke B.A.Sun W.h.Wang h.y.Bai Institute of Physics Chinese Academy of SciencesBeijing100190PR China College of Materials Science and Opto Electronic Technology University of Chinese Academy of SciencesBeijing100049PR China Songshan Lake Materials Laboratory DongguanGuangdong523808PR China

The fracture of metallic glasses(MGs)of different compositions and sizes down to micrometers under torsion loading were systematically *** to the flat shear fracture along the circumferential plane as commonly supposed under torsion,we find that the torsion fracture of metallic glasses can deviate from flat shear plane,and the fracture angle is closely dependent on the composition and the size of MG *** a conversion method,we show that the torsion fracture of both millimeterand micrometer-sized MGs can be described by the ellipse fracture criterion as originally proposed for the tension *** deviation from the circumferential shear plane under torsion is further shown to intrinsically relate to the fracture toughness of *** tougher MG tends to have a smaller fracture angle with respect to the maximum shear plane,and vice versa,indicating a correlation between the fracture toughness and pressure/normal stress sensitivity in *** results provide new insights on the fracture mechanism and are helpful to design and control the deformation and fracture behavior of MGs under torsion loading.

关键词： Metallic glasses Torsion fracture Pressure sensitivity Fracture toughness

Channel Estimation for Full-Duplex Relay Transmission in Cloud Radio Access Networks

在线全文

学校读者我要写书评

暂无评论

China Communications 2015年第11期12卷 35-42页

作者： hU Chunjing LI Jian MAO Zhendong ban yourong Key Laboratory of Universal Wireless Communication Ministry of EducationBeijing University of Posts and Telecommunications Department of Electrical Engineering University of Arkansas

Relay in full-duplex(FD) mode can achieve higher spectrum efficiency than that in half-duplex mode,while it is crucial to suppress relay self-interference to ensure transmission quality which requires instantaneous channel state information(CSI). In this paper,the channel estimation issue in FD amplify-andforward relay networks is considered,where the training-based estimation technique is adopted. Firstly,the least square(LS) estimation is implemented to obtain composite channel coefficients of source-relay-destination(SRD) channel and relay loop-interference(LI) channel in order to assist destination in performing data detection. Secondly,both LS and maximum likelihood estimation methods are utilized to perform individual channel estimation aiming at supporting successive interference cancelation at destination. Finally,simulation results demonstrate the effectiveness of both composite and individual channel estimation,and the presented ML method can achieve lower MSEs than LS solution.

关键词： channel estimation full-duplex cloud radio access networks

One-dimensional Ga N nanomaterials transformed from one-dimensional Ga_2O_3 and Ga nanomaterials

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2009年第1期1卷 4-8页

作者： X.y.han y.h.Gao X.h.Zhang Wuhan National Laboratory for Optoelectronics-Shool of Physics Huazhong University of Science and Technology Wuhan National Laboratory for Optoelectronics & Col ege of Optoelectronic Science and Engineering Huazhong University of Science and Technology

One-dimensional(1D) GaN nanomaterials exhibiting various morphologies and atomic structures were prepared via ammoniation of either Ga_2O_3 nanoribbons, Ga_2O_3 nanorods or Ga nanowires filled into carbon nanotubes(CNTs). The 1D GaN nanomaterials transformed from Ga_2O_3 nanoribbons consisted of numerous GaN nanoplatelets having the close-packed plane, i.e.(0002)2h or(111)3C parallel to the axes of starting nanoribbons. The 1D GaN nanomaterials converted from Ga_2O_3 nanorods were polycrystalline rods covered with GaN nanoparticles along the axes. The 1D GaN nanomaterials prepared from Ga nanowires filled into CNTs displayed two dominant morphologies:(i) single crystalline Ga N nanocolumns coated by CNTs, and(ii) pure single crystalline Ga N nanowires. The cross-sectional shape of Ga N nanowires were analyzed through the transmission electron microscopy(TEM) images. Formation mechanism of all-mentioned 1D GaN nanomaterials is then thoroughly discussed.

关键词： GaN One-dimensional Ga2O3 Nanostructures

Study of large area hydrogenated microcrystalline silicon p-layers for back surface field in crystalline silicon solar cells

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第1期54卷 63-69页

作者： ban Qun Martin hANKER Dietmar BORChERT ShEN hui Institute for Solar Energy System Sun Yat-sen University Guangzhou 510006 China Fraunhofer Institute for Solar Energy Systems Laboratory and Service Center Gelsenkirchen 45884 Germany

A series of hydrogenated microcrystalline silicon （μc-Si：h） p-layers for back surface field in crystalline silicon solar cells were deposited on glass substrates by the developed large area （45 cm×45 cm） plasma enhanced chemical vapour deposition processor operating at 13.56 Mhz and various values of source gas trimethylboron （TMB） to h2 flowratio. The influence of deposition parameters on the large area p-layer performance was intensively studied, as well as the thin film uniformity, optical, electrical and structural performances by Raman, PTIR, Ellipsometry, etc. Arrhenius and Tauc plots were used to discuss the μc-Si：h thin film＇s activation energy and the defects state distribution. When amorphous-microcrystalline transition state was obtained, the deposited p-doped μc-Si：h layers showed specific resistance of 38.3 Ω^-1cm1 at the flowratio of 0.66% and high crystallinity of 45%-50% with no further treatment. The effect of source gas flowratio, deposition rate, and source gas partial pressure on μc-Si：h thin film＇s performance was also investigated.

关键词： μc-Si:h flowratio uniformity band structure

Integration of power-to-hydrogen in day-ahead security-constrained unit commitment with high wind penetration

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2017年第3期5卷 337-349页

作者： Mingfei ban Jilai yU Mohammad ShAhIDEhPOUR yiyun yAO School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China Robert W.Galvin Center for Electricity Innovation Illinois Institute of TechnologyChicagoILUSA

The increasing integration of variable wind generation has aggravated the imbalance between electricity supply and demand. Power-to-hydrogen(P2h) is a promising solution to balance supply and demand in a variable power grid, in which excess wind power is converted into hydrogen via electrolysis and stored for later use. In this study, an energy hub(Eh) with both a P2h facility(electrolyzer) and a gas-to-power(G2P) facility(hydrogen gas turbine) is proposed to accommodate a high penetration of wind power. The Eh is modeled and integrated into a security-constrained unit commitment(SCUC) problem, and this optimization problem is solved by a mixed-integer linear programming(MILP) method with the Benders decomposition technique. Case studies are presented to validate the proposed model and elaborate on the technological potential of integrating P2h into a power system with a high level of wind penetration(hWP).

关键词： Electricity and natural gas coordination Power-to-hydrogen(P2h) Wind generation Security-constrained unit commitment(SCUC) Energy hub(Eh)

Multiple feature fusion for unimodal emotion recognition

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2019年第2期26卷 17-29页

作者： yang Lingzhi ban Xiaojuan Michele Mukeshimana Chen Zhe School of Computer and Communication Engineering Beijing Key Laboratory of Knowledge Engineering for Materials ScienceUniversity of Science and Technology BeijingBeijing 10083China Citic Pacific Special Steel holdings Qingdao Special Iron and Steel Company Limited Faculity of Engineering Sciences University of BurundiBujumbura P.0.Box 1550 BujumburaBurundi Qingdao hisense Group Company Limited Qingdao 266000China

A new semi-serial fusion method of multiple feature based on learning using privileged information(LUPI) model was put *** exploitation of LUPI paradigm permits the improvement of the learning accuracy and its stability,by additional information and computations using optimization *** execution time is also reduced,by sparsity and dimension of testing *** essence of improvements obtained using multiple features types for the emotion recognition(speech expression recognition),is particularly applicable when there is only one modality but still need to improve the *** results show that the LUPI in unimodal case is effective when the size of the feature is *** comparison to other methods using one type of features or combining them in a concatenated way,this new method outperforms others in recognition accuracy,execution reduction,and stability.

关键词： multiple feature LUPI emotion recognition semi-serial fusion method