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China Foundry 2022年第4期19卷 342-350页

作者： Yu-hao Chen Dun-ming Liao Wei-dong Li Tao Chen Ming Yang jun-ke shi State key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Luoyang Sunrui Titanium Precision Casting Co. Ltd.Luoyang 471003HenanChina Wuhan Chenxi Yunfeng Technology Co. Ltd.Wuhan 430074China

In the casting process,in order to compensate for the solidification shrinkage to obtain higher dimensional accuracy of the casting,it is often necessary to modify the original design of castings,and a suitable compensation method has a decisive impact on the dimensional accuracy of the actual *** this study,based on solidification simulation,a design method of reverse deformation is proposed,and two compensation methods,empirical compensation and direct reverse deformation,are *** simulation results show that the empirical compensation method has problems such as difficulty in determining the parameters and satisfaction of both the overall and local accuracy at the same time;while based on the simulation results for each node of the casting,the direct reverse deformation design achieves the design with *** addition,the casting model can be optimized through iterative revisions,so that higher dimensional accuracy can be continuously obtained in the subsequent design ***,the direct reverse deformation design is more accurate and reasonable compared to empirical compensation method.

关键词： casting simulation thermal stress deformation dimensional compensation dimensional accuracy

不同配重的浮球覆盖下干旱区平原水库的节水效率对比分析

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长江科学院院报 2017年第5期34卷 14-17页

作者：李存立严新军侍克斌新疆农业大学水利与土木工程学院乌鲁木齐830052

为达到抑制干旱区平原水库水分蒸发的目的,采用PVC浮球为试验材料,通过室内、外试验观测并分析无配重浮球在不同风速下的运动情况,探究浮球产生不规则旋转和翻滚运动的原因,并采取增加配重的办法对此问题加以解决。通过对比不同配重的... 详细信息

为达到抑制干旱区平原水库水分蒸发的目的,采用PVC浮球为试验材料,通过室内、外试验观测并分析无配重浮球在不同风速下的运动情况,探究浮球产生不规则旋转和翻滚运动的原因,并采取增加配重的办法对此问题加以解决。通过对比不同配重的浮球在不同气象条件下的湿润率并对其在试验期内的蒸发抑制率进行评价,结果表明:负载配重后的浮球比无配重的浮球的防蒸发节水效果更加显著,其水面综合蒸发抑制率最大可提高24%。研究成果为干旱区平原水库的节水措施提供了新思路。

关键词：干旱区平原水库节水效率配重浮球覆盖蒸发抑制率

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang Nan Zheng Qingming Lin Yan You Zheng Gong Yangping Zhuang Jiali Wu Yu Wang Hanlin Huang jun ke Feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

各向同性热解石墨表面金属化及AgCu钎料的润湿性能

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微波学报 2010年第S1期26卷 706-709页

作者：马天军赵世柯胡京军吴昆吕艳杰中国科学院电子学研究所北京100190

各向同性热解石墨作为一种新型的碳素材料由于具有许多优良的性能,而适宜制作真空电子器件的零部件。本文采用真空离子镀技术对其实现了表面金属化,并对金属化层从膜厚、组分、结合强度以及AgCu焊料的润湿性方面进行了性能分析。结果表... 详细信息

各向同性热解石墨作为一种新型的碳素材料由于具有许多优良的性能,而适宜制作真空电子器件的零部件。本文采用真空离子镀技术对其实现了表面金属化,并对金属化层从膜厚、组分、结合强度以及AgCu焊料的润湿性方面进行了性能分析。结果表明:真空离子镀CrNi层的力学性能良好,AgCu焊料在其表面的润湿性能良好。

关键词：热解石墨真空离子镀润湿性

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei Chen Nian Liu Jing He Jue shi Zihe Hu Yanyan Zhou Zhijian Xie Yong He State key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

Efficient channel blind estimator for multiuser system with conjugate cyclostationarity

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 1-6页

作者： ZHOU ke CAO shi-ke ZHANG Li-jun Communication and Information Engineering College Nanjing University of Posts and Telecommunications Nanjing 210003 China

The problem of blind channel identification in a multiuser system is considered in this article. For this purpose, a blind identification algorithm is proposed based on the conjugate cyclostationarity of the received signal. The new approach contains a two-stage identification procedure. First, the separation technique in the cyclic domain is used to separate the second-order cyclic statistics for each user. Second, a subspace algorithm based on the rational subspace theory is exploited to estimate the desired channel. Theoretical analysis and simulation results show that this algorithm is suitable for a multiuser system. Compared with other methods, the algorithm shows good performance even in a bad situation when the number of users is large and the diversity condition is unavailable.

关键词： conjugate cyclostationarity rational subspace theory subspace algorithm

Single-cell omics: experimental workflow, data analyses and applications

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Science China Life Sciences 2025年第1期68卷 5-102页

作者： Fengying Sun Haoyan Li Dongqing Sun Shaliu Fu Lei Gu Xin Shao Qinqin Wang Xin Dong Bin Duan Feiyang Xing jun Wu Minmin Xiao Fangqing Zhao Jing-Dong J.Han Qi Liu Xiaohui Fan Chen Li Chenfei Wang Tieliu shi Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang University key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji University) Ministry of EducationOrthopaedic DepartmentTongji HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Frontier Science Center for Stem Cells School of Life Sciences and TechnologyTongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Research Institute of Intelligent Computing Zhejiang Lab Shanghai Research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public HealthShanghai Jiao Tong University School of Medicine National key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang University Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biologythe Institute of Biomedical Sciences and School of Life SciencesEast China Normal University Beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesCenter for Quantitative Biology (CQB)Peking University Zhejiang key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women's HospitalZhejiang University School of Medicine key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of StatisticsEast China Normal University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial sc RNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

关键词： single-cell sequencing genome epigenome proteomics metabolomics multimodal spatial transcriptomics CRISPR screening

Performance Analysis of Anti-Interference UWB-OFDM System

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 6-9,38页

作者： ZHANG shi-bing CAO shi-ke ZHANG Li-jun Communication and Information Engineering Institute Nanjing University of Posts and Telecommunications Nanjing 210003 P.R. China School of Electronics and Information Nantong University Nantong 226007 P.R. China

This paper examines the robustness of anti-interference Ultra-Wide-Band UWB-OFDM （AI-UWB） systems in presence of narrow-band interference. It analyzes the bit error rate performance of the systems in both the single-user and multi-user modes, and compares its robustness in different code matrixes. By encoding transmitted symbols and spreading their power over all sub-bands, AI-UWB systems can make full use of the frequency diversity across the sub-bands and have more robustness to the narrowband interference. Simulating results show that different codes have almost the same robustness to the narrowband interference. The encoding and spreading could suppress the narrowband interference effectively. Compared with the IS-UWB systems, our approach has more than 5 dB interference margin.

关键词： UWB anti-interference bit error rate coding spreading

Towards Automatic Generation of As-built BIM:3D Building Facade Modeling and Material Recognition from Images

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International Journal of Automation and computing 2016年第4期13卷 338-349页

作者： jun Yang Zhong-ke shi Zi-Yan Wu School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an 710072 China School of Automation Northwestern Polytechnical University Xi'an 710072 China

As-built building information model （BIM） is an urgent need of the architecture, engineering, construction and facilities management （AEC/FM） community. However, its creation procedure is still labor-intensive and far from maturity. Taking advantage of prevalence of digital cameras and the development of advanced computer vision technology, the paper proposes to reconstruct a building facade and recognize its surface materials from images taken from various points of view. These can serve as initial steps towards automatic generation of as-built BIM. Specifically, 3D point clouds are generated from multiple images using structure from motion method and then segmented into planar components, which are further recognized as different structural components through knowledge based reasoning. Windows are detected through a multilayered complementary strategy by combining detection results from every semantic layer. A novel machine learning based 3D material recognition strategy is presented. Binary classifiers are trained through support vector machines. Material type at a given 3D location is predicted by all its corresponding 2D feature points. Experimental results from three existing buildings validate the proposed system.

关键词： As-built Building information models (BIM) image reconstruction modeling material recognition three dimensional

Theoretical Studies on the Hydrogen Bond Transfer and Proton Transfer between Anamorphoses of the Dihydrated Glycine Complex

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Chinese Journal of Structural Chemistry 2007年第5期26卷 580-586页

作者： WANG ke-Cheng MENG Xiang-jun shi Jin LI Bing-Huan Department of Chemistry Tangshan Teacher＇s College Tangshan 063000 China

The conversion between anamorphoses of the dihydrated glycine complex was studied by means of B3LYP/6-31＋＋G^＊＊. It was found that proton transfer was accompanied by hydrogen bond transfer in the process of conversion between different kinds of anamorphoses. With proton transfer, the electrostatic action was notably increased and the hydrogen-bonding action was evidently strengthened when the dihydrated neutral glycine complex converts into dihydrated zwitterionic glycine complex. The activation energy required for hydrogen bond transfer between dihydrated neutral glycine complexes is very low （6.32 kJ·mol^-1）; however, the hydrogen bond transfer between dihydrated zwitterionic glycine complexes is rather difficult with the required activation energy of 13.52 kJ·mol^-1 due to the relatively strong electrostatic action. The activation energy required by proton transfer is at least 27.33 kJ·mol^-1, higher than that needed for hydrogen bond transfer. The activation energy for either hydrogen bond transfer or proton transfer is in the bond-energy scope of medium-strong hydrogen bond, so the four kinds of anamorphoses of the dihydrated glycine complex could convert mutually.

关键词： intermolecular interaction B3LYP glycine,hydrogen bond transfer proton transfer