检索结果-南通市图书馆

Chemical Research in Chinese Universities 2007年第5期23卷 579-584页

作者： LIU Xiu-dong YU Wei-ting lin jun-zhang MA Xiao-jun YUAN Quan Laboratory of Biomedical Material Engineering Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P. R. China College of Environment and Chemical Engineering Dalian University Dalian 116622 P. R. China

Alginate has been widely used in cell microencapsulation and drug delivery systems in the form of gel beads or *** an alternative novel emulsification-internal gelation technology has been established and both the properties and the potential applications of the beads in drug delivery systems have been studied,the mechanism has not been well understood compared with the traditional droplet method（external gelation technology）.On the basis of our previous knowledge that the novel technology is composed of complicatedly consecutive processes with multistep diffusion and reaction,and the diffusion of acetic acid across oil/water interface being the prerequisite that determines the occurrence and rate for the reactions and the structures and properties of final produced gel beads,a special emphasis was placed on the diffusion *** the aid of diffusion modeling and simple experimental design,the diffusion rate constant and diffusion coefficient of acetic acid across oil/water interface were determined to be in the orders of magnitude of 10-6 and 10-16,*** knowledge will be of particular importance in understanding and interpreting the formation,structure of the gel beads and the relationship between the structure and properties and guiding the preparation and quality control of the gel beads.

关键词： Emulsification-internal gelation technology Alginate Gel bead Diffusion rate constant Diffusion coefficient

An Interfacial Dynamic Crosslinking Approach toward Catalyst-free and Mechanically Robust Elastomeric Vitrimer with a Segregated Structure

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2021年第2期39卷 201-210,I0007页

作者： Yong Zhu Jing-Li Gao lin-jun zhang Yan Peng Hao Wang Fang-Wei ling Guang-Su Huang Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

Elastomeric vitrimers with covalent adaptable networks are promising candidates to overcome the intrinsic drawbacks of conventional covalently-crosslinked elastomers;however, most elastomeric vitrimers show poor mechanical properties and require the addition of exogenous catalysts. Herein, we fabricate a catalyst-free and mechanically robust elastomeric vitrimer by constructing a segregated structure of sodium alginate (SA) in the continuous matrix of epoxidized natural rubber (ENR), and further crosslinking the composite by exchangeable hydroxyl ester bonds at the ENR-SA interfaces. The manufacturing process of the elastomeric vitrimer is facile and environmentally friendly without hazardous solvents or exogenous catalysts, as the abundant hydroxyl groups of the segregated SA phase can act as catalyst to activate the crosslinking reaction and promote the dynamic transesterification reaction. Interestingly, the segregated SA structure bears most of the load owing to its high modulus and small deformability, and thus ruptures preferentially upon deformation, leading to efficient energy ***, the periodic stiffness fluctuation between rigid segregated SA phase and soft ENR matrix is beneficial to the crack-resisting. As a result,the elastomeric vitrimer manifests exceptional combination of catalyst-free, defect-tolerance, high tensile strength and toughness. In addition,the elastomeric vitrimer also exhibits multi-shape memory behavior which may further broaden its applications.

关键词： Tough Defect-tolerant Elastomeric vitrimer Interfacial dynamic crosslinks Segregated structure

System utility based resource allocation for multi-cell OFDM system

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 2010年第2期17卷 14-18,45页

作者： HAO Zhi-jie XU Xiao-dong ZHAO Ying-hong TAO Xiao-feng LI lin-jun zhang Zhong-qi Wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Utility based resource allocation strategy in multi-cell orthogonal frequency-division multiplexing （OFDM） system plays a critical role in next generation mobile communication systems. Based on the analysis of risk aversion utility functions, this article proposed the system utility based utility, which is named the customer satisfaction （CS） utility. Compared with the proportional fairness （PF） utility, the CS utility reflects the user demands better, and enables the system to adjust its resource allocation according to both the traffic requirements and the resource situation.

关键词： OFDM resource allocation utility multi-cell

Development and application of an intelligent thermal state monitoring system for sintering machine tails based on CNN-LSTM hybrid neural networks

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2025年第1期32卷 52-63页

作者： Da-lin Xiong Xin-yu zhang Zheng-wei Yu Xue-feng zhang Hong-ming Long Liang-jun Chen Anhui Province Key Laboratory of Metallurgical Engineering&Resources Recycling Anhui University of TechnologyMa’anshan243002AnhuiChina School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina School of Computer Science Anhui University of TechnologyMa’anshan243032AnhuiChina

Real-time prediction and precise control of sinter quality are pivotal for energy saving,cost reduction,quality improvement and efficiency enhancement in the ironmaking *** advance,the accuracy and comprehensiveness of sinter quality prediction,an intelligent flare monitoring system for sintering machine tails that combines hybrid neural networks integrating convolutional neural network with long short-term memory(CNN-LSTM)networks was *** system utilized a high-temperature thermal imager for image acquisition at the sintering machine tail and employed a zone-triggered method to accurately capture dynamic feature images under challenging conditions of high-temperature,high dust,and *** feature images were then segmented through a triple-iteration multi-thresholding approach based on the maximum between-class variance method to minimize detail loss during the segmentation *** the advantages of CNN and LSTM networks in capturing temporal and spatial information,a comprehensive model for sinter quality prediction was constructed,with inputs including the proportion of combustion layer,porosity rate,temperature distribution,and image features obtained from the convolutional neural network,and outputs comprising quality indicators such as underburning index,uniformity index,and FeO content of the *** accuracy is notably increased,achieving a 95.8%hit rate within an error margin of±*** the system is applied,the average qualified rate of FeO content increases from 87.24%to 89.99%,representing an improvement of 2.75%.The average monthly solid fuel consumption is reduced from 49.75 to 46.44 kg/t,leading to a 6.65%reduction and underscoring significant energy saving and cost reduction effects.

关键词： Sinter quality Convolutional neural network Long short-term memory Image segmentation FeO prediction

Molecular Characterization and Expression Pattern of Rheb Gene in Inner Mongolia Cashmere Goat(Capra hircus)

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

Agricultural Sciences in China 2011年第9期10卷 1452-1458页

作者： ZHENG Xu YANG Jiao-fu WANG Xiao-jing LIANG Yan WU Man-lin SHI Jie-jun zhang Tao QIN Yin LI Shu-yu HAO Xi-yan WANG Zhi-gang LIU Dong-jun College of Life Science lnner Mongolia University/Key Laboratory of Mammal Reproductive Biology and Biotechnology Ministry of Education Hohhot 010021 P.R.China

As one member of the Ras super family, Rheb is an upstream regulator of mTOR signaling pathway, which regulates the process of cell-growth, proliferation and differentiation. In order to study the relationship between Rheb and mTOR in Inner Mongolian Cashmere goat （Capra hircus） cells, Ras homolog enriched in brain （Rheb） gene eDNA was amplified by RT-PCR. It is 555 bp in length and includes the complete ORF encoding 184 amino acids （GenBank accession no. HM569224）. The full eDNA nucleotide sequence has a 99% identity with that of sheep, 98% with cattle and 93% with human while their amino acids sequence shares identity with 98, 97 and 97% of them, correspondingly. The bioinformatics analysis showed that Rheb has a Ras family domain, two casein kinase II phosphorylation sites, two ATP/GTP-binding sites motifA （P-loop）, a prenyl group binding site （CAAX box）. Tissue-specific expression analysis performed by semi- quantitative RT-PCR. The Rheb gene was expressed in all the tested tissues and the highest level ofmRNA accumulation was detected in brain, suggesting that Rheb played an important role in goat cells.

关键词： Inner Mongolia Cashmere goat Rheb gene expression pattern

Partial multi-label learning via label-specific feature corrections

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2025年第03期68卷 95-109页

作者： jun-Yi HANG Min-ling zhang School of Computer Science and Engineering Southeast University Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of Education

Partial multi-label learning（PML） allows learning from rich-semantic objects with inaccurate annotations, where a set of candidate labels are assigned to each training example but only some of them are valid. Existing approaches rely on disambiguation to tackle the PML problem, which aims to correct noisy candidate labels by recovering the ground-truth labeling information ahead of prediction model induction. However, this dominant strategy might be suboptimal as it usually needs extra assumptions that cannot be fully satisfied in real-world scenarios. Instead of label correction, we investigate another strategy to tackle the PML problem, where the potential ambiguity in PML data is eliminated by correcting instance features in a label-specific manner. Accordingly, a simple yet effective approach named PASE, i.e., partial multi-label learning via label-specific feature corrections, is proposed. Under a meta-learning framework, PASElearns to exert label-specific feature corrections so that potential ambiguity specific to each class label can be eliminated and the desired prediction model can be induced on these corrected instance features with the provided candidate labels. Comprehensive experiments on a wide range of synthetic and real-world data sets validate the effectiveness of the proposed approach.

关键词： machine learning multi-label learning partial multi-label learning label-specific features feature correction

同方期刊数据库

A STUDY OF THE REACTIONS OF BENZYL ETHERS WITH DIBROMOCARBENE

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1992年第4期3卷 259-262页

作者： Qi jun lin & Miao zhang Department of chemistry and applied chemistry, Shandong University, Jinan, Shandong, 250100

Using potassium carbonate as base and a polyethylene glycol with an average molecular weight of 600 (PGE600) as phase transfer catalyst, reaction of benzyl ethers with dibromocarbene leads to benzylic C—H bond insert... 详细信息

关键词： A STUDY OF THE REACTIONS OF BENZYL ETHERS WITH DIBROMOCARBENE

Numerical Study of Flow and Heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric Heater with Circularly Perforated Baffles

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2025年第1期34卷 24-33页

作者： lin Yongjie zhang Cancan WU Yuting zhang Yi LU Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of TechnologyBeijing 100124China

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings(φ),i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/(Δp)^(1/3)was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29%to 17.18%over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer

Turbulent Agglomeration of Microparticles in a Cylinder Wake Flow Using LES-DEM:Focusing on the Effect of the Reynolds Number

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2025年第1期34卷 34-49页

作者： WANG Shuang MU lin LI Xue XIE jun DONG Ming School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China School of Optical Information and Energy Engineering Wuhan Institute of TechnologyWuhan 430205China School of Energy and Environment Shenyang Aerospace UniversityShenyang 110136China

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method(LES-DEM)*** validity of the LES approach was verified by comparison with available direct numerical simulation(DNS)*** adopted the Johnson-Kendall-Roberts(JKR)contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters(d_(p)=2-20μm)in the laminar and transition of shear layer(TrSL)flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise(y-direction).With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

关键词： microparticle particle agglomeration discrete element method large eddy simulation

Aerodynamic Optimization and Flow Mechanism for a Compressor Cascade at Low Reynolds Number

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2025年第1期34卷 92-109页

作者： LI lin zhang Jianshe CHEN Caiyan TAN Wei zhang Yanfeng Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Beijing 100190China

Low-Reynolds-number effect is an important factor affecting the performance of compressors and other main components of high-altitude long-endurance unmanned aerial *** improve the flow condition and reduce flow loss under the condition of high altitude and low Reynolds number(Re),this paper proposes an optimization process based on a surrogate model,which combines the class-shape transformation method(CST),the Latin hypercube sampling(LHS)method,the light gradient-boosting machine algorithm(LightGBM),and a genetic algorithm(GA)to optimize a high-subsonic compressor *** surrogate model is verified to be accurate and can be used in the optimization *** accuracy of the GA is higher than the other algorithms under common test *** optimization results are verified by numerical simulation,and the flow differences before and after optimization are compared,especially the flow within the boundary *** changing the blade shape,the optimization process adjusts the loading distribution to delay the transition of the optimized blade on the suction surface,which changes the turbulent reattachment in the laminar separation bubble(LSB)into laminar ***,the mixing loss induced by the turbulent reattachment of the LSB and the wake loss of turbulent separation at the trailing edge are significantly reduced,and the performance of the compressor profile is finally *** addition,turbulent separation of the optimized profile is delayed reducing the range of the wake region on the suction *** this optimization process,the reduction of total pressure loss coefficient at Re of 2.5×10^(5),3.5×10^(5),and 4.5×10^(5) are 16.32%,20.76%,and 22.16%,respectively.

关键词： low Reynolds numbers compressor optimization boundary layer transition