检索结果-南通市图书馆

Topology Optimization of Two Fluid Heat Transfer Problems for Heat Exchanger Design

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第8期140卷 1949-1974页

作者： kun Yan Yunyu wang Jun Yan School of Chemical Engineering Dalian University of TechnologyDalian116024China Jianghuai Advanced Technology Center Hefei230000China State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian116024China

Topology optimization of thermal-fluid coupling problems has received widespread *** article proposes a novel topology optimization method for laminar two-fluid heat exchanger *** proposed method utilizes an artificial density field to create two permeability interpolation functions that exhibit opposing trends,ensuring separation between the two fluid ***,a Gaussian function is employed to construct an interpolation function for the thermal conductivity ***,a computational program has been developed on the OpenFOAM platform for the topology optimization of two-fluid heat *** program leverages parallel computing,significantly reducing the time required for the topology optimization *** enhance computational speed and reduce the number of constraint conditions,we replaced the conventional pressure drop constraint condition in the optimization problem with a pressure inlet/outlet boundary *** 3D optimization results demonstrate the characteristic features of a surface structure,providing valuable guidance for designing heat exchangers that achieve high heat exchange efficiency while minimizing excessive pressure *** the same time,a new structure appears in large-scale topology optimization,which proves the effectiveness and stability of the topology optimization program written in this paper in large-scale calculation.

关键词： Topology optimization two fluid heat exchanger OpenFOAM large scale

Robust enhancement of valley polarization and quantum yield in composition grading lateral heterostructure of MoS2-WS2 monolayer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2024年第1期34卷 187-193页

作者： Mengke Kang Cheng Zhang Congpu Mu kun Zhai Tianyu Xue Bochong wang Fusheng Wen Yingchun Cheng Jianyong xiang Jun-Feng Dai Anmin Nie Zhongyuan Liu Center for High Pressure Science State Key Laboratory of Metastable Materials Science and Technology Yanshan University Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology Shenzhen Key Laboratory of Quantum Science and Engineering

Valley degeneracy can be broken owing to the strong spin-orbit coupling in two-dimensional transition metal dichalcogenides（2D-TMDCs）. Valley-dependent interaction of carriers in TMDCs with different circular polarizations of light offers valley degree-of-freedom besides charge and spin to carry information. Thus, bandgap engineering of 2D-TMDCs plays a critical role in developing practical valleytronic devices. Hereby, we demonstrate a great enhancement in quantum yield as well as polarization of monolayer MoS2achieved by gradually alloying W atoms in MoS2. By appropriately setting a time offset between the evaporation of MoO3and WO3precursors during chemical vapor deposition, a compositionally graded heterostructure of MoS2-WS2monolayer can be readily grown at large scale. Raman and transmission electron microscopy measurements demonstrate that the interface possesses a steep gradient in composition, spanning from MoS2to WS2over a length ～2 μ*** to pure monolayer MoS2, the photoluminescence intensity at the compositionally graded interface of Mo1-xWxS2was observed to increase by a factor of 16 owing to the effective separation of photogenerated carriers by the built-in electric field. Particularly, a remarkably high polarization of 70% at 16 K is demonstrated for the compositionally graded interface of Mo1-xWxS2, which is ～1.4 times larger than that in MoS2and is attributed to the combined effect of the alloyed structure and graded bandgap. Such an engineering scheme with a graded bandgap offers new approach for the development of high-efficiency valleytronics devices.

关键词： Transition metal dichalcognide monolayer Compositionally graded in-plane heterostructure Chemical vapor deposition Valley polarization Quantum yield

A chromosome-level genome assembly for Chinese plum‘Wushancuili'reveals the molecular basis of its fruit color and susceptibility to rain-cracking

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Horticultural Plant Journal 2024年第3期10卷 672-688页

作者： kun Zhou Jingwen wang Lin Pan Fang xiang Yi Zhou Wei Xiong Ming Zeng Donald Grierson Wenbin Kong Lingyu Hu Wanpeng Xi College of Horticulture and Landscape Architecture Southwest UniversityChongqing 400715China Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River(Ministry of Education) Southwest UniversityChongqing 400715China Department of Pomology Chongqing Agricultural Technology Extension StationChongqing 401420China Plant and Crop Sciences Division School of BiosciencesUniversity of NottinghamSutton Bonington CampusLoughborough LE125RDUK Wuxi Economical Crop Technology Extension Station Chongqing 405800China

Chinese plum(Prunus salicina Lindl.)originates from China and makes a large contribution to the global production of *** ***‘Wushancuili'has a green coloration and high fruit quality and is economically important in eliminating poverty and protecting ecology in the Yangtze River Three Gorges ***,rain-induced cracking(rain-cracking,literally skin cracking caused by rain)is a limitation to‘Wushancuili'fruit production and causes severe *** study reported a high-quality‘Wushancuili'genome assembly consisting of a 302.17-Mb sequence with eight pseudo-chromosomes and a contig N50 of 23.59 Mb through the combination of Illumina sequencing,Pacific Biosciences HiFiⅢsequencing,and high-throughput chromosome conformation capture technology.A total of 25109 protein-coding genes are predicted and 54.17%of the genome is composed of repetitive sequences.‘Wushancuili'underwent a remarkable orthoselection during *** identification revealed that loss-of-function in four core MYB10 genes results in the anthocyanin deficiency and absence of red color,revealing the green coloration due to the residual high chlorophyll in fruit ***,the occurrence of cracking is assumed to be closely associated with cell wall modification and frequently rain-induced pathogen enrichment through transcriptomic *** loss of MYB10 genes might render fruit more susceptible to pathogen-mediated cracking by weakening the epidermal strength and reactive oxygen species(ROS)*** findings provided fundamental knowledge regarding fruit coloration and rain-cracking and will facilitate genetic improvement and cultivation management in Chinese plums.

关键词： Chinese plum Fruit coloration Fruit epidermis Genome MYB10 Rain-cracking

Success rate of current human-derived gastric cancer organoids establishment and influencing factors:A systematic review and meta-analysis

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第4期16卷 1626-1646页

作者： Kai-Lin Jiang xiang-xiang wang Xue-Jiao Liu Li-kun Guo Yong-Qi Chen Qing-Ling Jia Ke-Ming Yang Jiang-Hong Ling Department of Gastroenterology Shuguang HospitalShanghai 200021China Department of Pathology Shuguang HospitalShanghai 200021China

BACKGROUND Human-derived gastric cancer organoids(GCOs)are widely used in gastric cancer research;however,the culture success rate is generally *** To explore the potential influencing factors,and the literature on successful culture rates of GCOs was reviewed using *** PubMed,Web of Science,and EMBASE were searched for *** trained researchers selected the studies and extracted *** 17.0 software was used for meta-analysis of the incidence of each outcome *** adjusted Methodological Index for Non-Randomized Studies scale was used to assess the quality of the included *** plots and Egger’s test were used to detect publication *** analyses were conducted for sex,tissue source,histo-logical classification,and the pathological tumor-node-metastasis(pTNM)cancer staging *** Eight studies with a pooled success rate of 66.6%were *** derived from women and men had success rates of 67%and 46.7%,*** from surgery or biopsy/endoscopic submucosal dissection showed success rates of 70.9%and 53.7%,*** of poorly-differentiated,moderately-differentiated and signet-ring cell cancer showed success rates of 64.6%,31%,and 32.7%,*** with pTNM stages I-II and III-IV showed success rates of 38.3%and 65.2%,respectively.Y-27632 and non-Y-27632 use showed success rates of 58.2%and 70%,*** generated with collagenase were more successful than those constructed with Liberase TH and TrypLE(72.1%vs 71%,respectively).EDTA digestion showed a 50%lower success rate than other methods(P=0.04).CONCLUSION GCO establishment rate is low and varies by sex,tissue source,histological type,and pTNM *** Y-27632,and using Liberase TH,TrypLE,or collagenase yields greater success than EDTA.

关键词： Gastric cancer organoids Human-derived organoids Gastric cancer Cell lines In vitro research models

Classification of spin Hall effect in two-dimensional systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第3期19卷 103-114页

作者： Longjun xiang Fuming Xu Luyang wang Jian wang College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Quantum Science Center of Guangdong-Hongkong-Macao Greater Bay Area(Guangdong) Shenzhen 518045China Department of Physics The University of Hong KongPokfulam RoadHong KongChina

Physical properties such as the conductivity are usually classified according to the symmetry of the underlying system using Neumann’s principle, which gives an upper bound for the number of independent components of the corresponding property tensor. However, for a given Hamiltonian, this global approach usually can not give a definite answer on whether a physical effect such as spin Hall effect (SHE) exists or not. It is found that the parity and types of spin-orbit interactions (SOIs) are good indicators that can further reduce the number of independent components of the spin Hall conductivity for a specific system. In terms of the parity as well as various Rashba-like and Dresselhaus-like SOIs, we propose a local approach to classify SHE in two-dimensional (2D) two-band models, where sufficient conditions for identifying the existence or absence of SHE in all 2D magnetic point groups are presented.

关键词： spin Hall effect symmetry two-dimensional system

Using MsfNet to Predict the ISUP Grade of Renal Clear Cell Carcinoma in Digital Pathology Images

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 393-410页

作者： kun Yang Shilong Chang Yucheng wang Minghui wang Jiahui Yang Shuang Liu kun Liu Linyan Xue College of Quality and Technical Supervision Hebei UniversityBaoding071002China National and Local Joint Engineering Research Center of Metrology Instrument and System Hebei UniversityBaoding071002China Hebei Technology Innovation Center for Lightweight of New Energy Vehicle Power System Hebei UniversityBaoding071002China

Clear cell renal cell carcinoma(ccRCC)represents the most frequent form of renal cell carcinoma(RCC),and accurate International Society of Urological Pathology(ISUP)grading is crucial for prognosis and treatment *** study presents a new deep network called Multi-scale Fusion Network(MsfNet),which aims to enhance the automatic ISUP grade of ccRCC with digital histopathology pathology *** MsfNet overcomes the limitations of traditional ResNet50 by multi-scale information fusion and dynamic allocation of channel *** model was trained and tested using 90 Hematoxylin and Eosin(H&E)stained whole slide images(WSIs),which were all cropped into 320×320-pixel patches at 40×*** achieved a micro-averaged area under the curve(AUC)of 0.9807,a macro-averaged AUC of 0.9778 on the test *** Gradient-weighted Class Activation Mapping(Grad-CAM)visually demonstrated MsfNet’s ability to distinguish and highlight abnormal areas more effectively than *** t-Distributed Stochastic Neighbor Embedding(t-SNE)plot indicates our model can efficiently extract critical features from images,reducing the impact of noise and redundant *** results suggest that MsfNet offers an accurate ISUP grade of ccRCC in digital images,emphasizing the potential of AI-assisted histopathological systems in clinical practice.

关键词： Renal cell carcinoma computer-aided diagnosis pathology image deep learning machine learning

Optimizing hemicelluloses pre-extraction in eucalyptus kraft pulping:A pathway towards enhancing pulp mill biorefineries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第6期70卷 162-172页

作者： Yuhan wang Danqi Xue Jingjing Zhuo Zhouyang xiang State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640China

A critical pathway towards enhancing pulp mill biorefineries is to integrate the extraction and utilization of hemicelluloses into the pulping ***,an industrial pre-extraction strategy for hemicelluloses targeting eucalyptus kraft pulping process was *** solution or pulping white liquor was used to pre-extract hemicelluloses before the actual pulping *** response surface methodology(RSM)technique was applied to investigate the most suitable conditions to maximize the yield of these hemicelluloses while simultaneously minimizing the damage to pulp yields and ***(105 to 155℃),alkali concentration(3%to 8%),sulfidity(20%to 30%)and retention time(19 to 221 min)were combined to evaluate their effects on hemicellulose yields and chemical *** optimal pre-extraction conditions identified in this work(5.75%NaOH concentration,25%sulfidity at 135℃for 60 min)successfully allowed recovering 4.8%of hemicelluloses(based on the wood dry mass)and limited damages to pulp yields and *** cellulose content in pulp can even be increased by about 10%.Hemicellulose emulsification properties were also evaluated,which were comparable to synthetic *** study provides an industrial pathway to effectively separate and utilize wood hemicelluloses from the pulping process,which has the potential to improve the economy and material utilization of pulp and paper mills.

关键词： Hemicelluloses Xylan Pre-extraction Kraft pulping Emulsifying Response surface methodology(RSM)

Thermal fatigue and wear of compacted graphite iron brake discs with various thermomechanical properties

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第3期21卷 248-256页

作者： Gui-quan wang Zhuo Xu Zhong-li Liu xiang Chen Yan-xiang Li School of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005ShandongChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China

The increase in payload capacity of trucks has heightened the demand for cost-effective yet high performance brake *** this work,the thermal fatigue and wear of compacted graphite iron brake discs were investigated,aiming to provide an experimental foundation for achieving a balance between their thermal and mechanical *** graphite iron brake discs with different tensile strengths,macrohardnesses,specific heat capacities and thermal diffusion coefficients were produced by changing the proportion and strength of *** peak temperature,pressure load and friction coefficient of compacted graphite iron brake discs were analyzed through inertia friction *** morphology of thermal cracks and 3D profiles of the worn surfaces were also *** is found that the thermal fatigue of compacted graphite iron discs is determined by their thermal properties.A compacted graphite iron with the highest specific heat capacity and thermal diffusion coefficient exhibits optimal thermal fatigue *** of the matrix at low temperatures significantly weakens the function of alloy strengthening in hindering the propagation of thermal *** the reduced hardness,increasing the ferrite proportion can mitigate wear loss resulting from low disc temperatures and the absence of abrasive wear.

关键词： compacted graphite iron brake disc thermomechanical properties thermal fatigue wear

Discovering Latent Variables for the Tasks With Confounders in Multi-Agent Reinforcement Learning

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1591-1604页

作者： kun Jiang Wenzhang Liu Yuanda wang Lu Dong Changyin Sun the School of Automation Southeast UniversityNanjing 210096China the School of Artificial Intelligence Anhui UniversityHefei 230601China IEEE the School of Cyber Science and Engineering Southeast UniversityNanjing 211189China the Engineering Research Center of Autonomous Unmanned System Technology Ministry of EducationHefei 230601China

Efficient exploration in complex coordination tasks has been considered a challenging problem in multi-agent reinforcement learning(MARL). It is significantly more difficult for those tasks with latent variables that agents cannot directly observe. However, most of the existing latent variable discovery methods lack a clear representation of latent variables and an effective evaluation of the influence of latent variables on the agent. In this paper, we propose a new MARL algorithm based on the soft actor-critic method for complex continuous control tasks with confounders. It is called the multi-agent soft actor-critic with latent variable(MASAC-LV) algorithm, which uses variational inference theory to infer the compact latent variables representation space from a large amount of offline ***, we derive the counterfactual policy whose input has no latent variables and quantify the difference between the actual policy and the counterfactual policy via a distance function. This quantified difference is considered an intrinsic motivation that gives additional rewards based on how much the latent variable affects each agent. The proposed algorithm is evaluated on two collaboration tasks with confounders, and the experimental results demonstrate the effectiveness of MASAC-LV compared to other baseline algorithms.

关键词： Latent variable model maximum entropy multi-agent reinforcement learning(MARL) multi-agent system