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A Study on the Impact of Chemical Structure on the Evolution of Aggregate Structure in Fiber-shaped High Density Polyethylene Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1557-1565,I0013页

作者： bing Wang Yuan-chu Gao Hai Wang Hui Niu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China

Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shaped HDPE vitrimers through a reaction extrusion and post-drawing *** chemical structure characterization,morphology observation,thermal and mechanical properties investigation,as well as aggregate structure analysis,this work revealed the influence of dynamic bonds on the formation of aggregate structures during fiber-shaped vitrimers processing.A small amount of dynamic bonds in HDPE restricts the motion of PE chain during melt-extruding and post-drawing,resulting in a lower orientation of the PE ***,lamellar growth and fibril formation during post-drawing at high temperature are enhanced to some extent due to the competition between dynamic bond and chain *** uneven morphology of fibershaped HDPE vitrimers can be attributed to the stronger elastic effect brought by dynamic bonding,which plays a more dominant role in determining the mechanical properties of fiber-shaped vitrimers compared to aggregate *** Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shap

关键词： High density polyethylene vitrimer Fiber-shaped Aggregate structures Transesterification reaction

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Mapping Changes of Whole Brain Blood Flow in Rats with Myocardial Ischemia/Reperfusion Injury Assessed by Positron Emission Tomography

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Current Medical Science 2019年第4期39卷 653-657页

作者： Xu-chu PAN zhi-xiao LI Duo-zhi WU Shun-yuan LI Hong-bing XIANG Yong-tang SONG Medical Association of Hubei Province Wuhan 430071China Department of Anesthesiology and Pain Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Anesthesiology Hainan General HospitalHaikou 570311China Department of Anesthesiology the First Affiliated Quanzhou Hospital of Fujian Medical UniversityQuanzhou 362000China

l8F-labeled fluorodeoxyglucose positron emission tomography (l8F-FDG PET) is the most sensitive tool for studying brain metabolism in *** investigated the image patterns of 18F-FDG PET during reperfusion injury and correlated changes of whole brain blood flow utilizing a rat myocardial ischemia/reperfiision injury (MIRI) *** results assessed by echocardiography indicated resultant cardiac dysfunction after ischemia-reperfusion in the rat *** was found that the average standardized uptake value (SUVaverage) of the whole brain was significantly decreased in model rats,and the glucose uptake of different brain regions including accumbens core/shell (Acb),left caudate putamen (LCPu),hippocampus (HIP),left hypothalamus (LHYP),olfactory (OLF),superior colliculus (SC),right midbrain (RMID),ventral tegmental area (VTA),inferior colliculus (IC) and left thalamus whole (LTHA) was significantly decreased in MIRI rats whereas no significant difference was found in the SUVaverage of amygdala (AMY),right Cpu,RHYP,right HYP,left MID,right THA,pons and medulla oblongata (MO).These l8F-FDG PET data provide a reliable identification method for brain metabolic changes in rats with MIRI.

关键词： cardiac ischemia-reperfusion injury brain metabolism 18-fluorodeoxyglucose positron emission tomography

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Comparison of pyrolysis characteristics of two Chinese oil shales based onthe migration and conversion of organic carbon

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Carbon Resources Conversion 2018年第3期1卷 209-217页

作者： zhi-bing Chang Mo chu Chao Zhang Shu-xia Bai Sheng-tao Wang Bao-man Liu School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China

In this study,the Huadian oil shale(HD-R)and Balikun oil shale(BLK-R)were pyrolyzed in a fixed-bed pyrolyzer at 360–530℃.Based on the migration and conversion of organic carbon,their pyrolysis characteristics were investigated and *** aliphaticity of Huadian kerogen(HD-K)and Balikun kerogen(BLK-K)are 80.53%and 52.83%,*** HD-K contains more C=O,which will render the depolymerization and decomposition of kerogen to occur at low temperatures to produce volatile ***,the cumulative conversion of the Huadian shale oil is greater than the Balikun shale oil at 390–435℃.The aliphatic carbons of the BLK-K are mainly present as short methylene chains attached to aromatic *** will leave the kerogen matrix with the breakage of relatively weaker CeC bonds at β-sites from aromatic rings at medium *** contrast,aliphatic carbons of the HD-K are dominated by long aliphatic *** temperature is necessary to break other stronger CeC to form shale oil and gaseous species,which appears to make the oil accumulation conversion of BLK-R exceed that of HD-R at 450–510℃.

关键词： Oil shale Pyrolysis Kerogen Organic carbon Thermal bitumen Shale oil

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The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

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Research in Astronomy and Astrophysics 2024年第5期24卷 140-150页

作者： zhi-chu Ma Rui Niu Wen Zhao CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

关键词： gravitational waves-gravitation-black hole physics

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Physical exercise suppresses hepatocellular carcinoma progression by alleviating hypoxia and attenuating cancer stemness through the Akt/GSK-3β/β-catenin pathway

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Journal of Integrative Medicine 2023年第2期21卷 184-193页

作者： chu-lan Xiao zhi-peng Zhong Can Lü bing-jie Guo Jiao-jiao Chen Tong Zhao Zi-fei Yin Bai Li Department of Rehabilitation Changhai HospitalNaval Medical UniversityShanghai 200433China Department of Traditional Chinese Medicine The 920th Hospital of Joint Logistics Support ForceKunming 650000Yunnan ProvinceChina Second Team Graduate SchoolNaval Medical UniversityShanghai 200433China College of Integrated Traditional Chinese and Western Medicine Nanjing University of Traditional Chinese MedicineNanjing 210023Jiangsu ProvinceChina Department of Military Traditional Chinese Medicine Faculty of Traditional Chinese MedicineNaval Medical UniversityShanghai 200433China

Objective:Physical exercise,a common non-drug intervention,is an important strategy in cancer treatment,including hepatocellular carcinoma(HCC).However,the mechanism remains largely *** to the importance of hypoxia and cancer stemness in the development of HCC,the present study investigated whether the anti-HCC effect of physical exercise is related to its suppression on hypoxia and cancer ***:A physical exercise intervention of swimming(30 min/d,5 d/week,for 4 weeks)was administered to BALB/c nude mice bearing subcutaneous human HCC *** anti-HCC effect of swimming was assessed in vivo by tumor weight monitoring,hematoxylin and eosin(HE)staining,and immunohistochemistry(IHC)detection of proliferating cell nuclear antigen(PCNA)and *** expression of stemness transcription factors,including Nanog homeobox(NANOG),octamer-binding transcription factor 4(OCT-4),v-Myc avian myelocytomatosis viral oncogene homolog(C-MYC)and hypoxia-inducible factor-1a(HIF-1a),was detected using real-time reverse transcription polymerase chain reaction.A hypoxia probe was used to explore the intratumoral hypoxia *** blot was used to detect the expression of HIF-1a and proteins related to protein kinase B(Akt)/glycogen synthase kinase-3β(GSK-3β)/β-catenin signaling *** IHC analysis of platelet endothelial cell adhesion molecule-1(CD31),and the immunofluorescence co-location of CD31 and desmin were used to analyze tumor blood ***-7721 cells were treated with nude mice *** inhibition effect on cancer stemness in vitro was detected using suspension sphere experiments and the expression of stemness transcription *** hypoxia status was inferred by measuring the protein and mRNA levels of ***,the expression of proteins related to Akt/GSK-3β/β-catenin signaling pathway was ***:Swimming significantly reduced the body weight and tumor weight in nude mice bearing HCC *** staining and IHC results show

关键词： Physical exercise Swimming Hepatocellular carcinoma Liver cancer Blood perfusion Hypoxia Cancer stemness Akt/GSK-3β/β-catenin

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Effect of sintering temperature on the microstructure and thermal conductivity of Al/diamond composites prepared by spark plasma sintering

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 234-240页

作者： Ke chu Cheng-chang Jia Xue-bing Liang Hui Chen School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Spark plasma sintering was used to fabricate Al/diamond *** effect of sintering temperature on the microstructure and thermal conductivity（TC） of the composites was investigated with the combination of experimental results and theoretical *** composite sintered at 550℃shows high relative density and strong interfacial bonding,whereas the composites sintered at lower（520CC） and higher（580-600℃） temperatures indicate no interfacial bonding and poor interfacial bonding,*** relative density and strong interfacial bonding can maximize the thermal conductivity of Al/diamond composites,and taking both effects of particle shape and inhomogeneous interfacial thermal conductance into consideration can give a fairly good prediction of composites＇ thermal conduction properties.

关键词： metal matrix composites thermal properties spark plasma sintering interface

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Multistage desulfurization mechanism to reduce sulfur content of high ferrotitanium prepared using thermite method

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Rare Metals 2021年第8期40卷 2313-2319页

作者： chu Cheng zhi-He Dou Ting-An Zhang Yu-Lai Song Collaborative Innovation Center of Nonferrous Metals Henan Province School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang471003China Key Laboratory of Ecological Utilization of Multi-metal Intergrown Ores of Ministry of Education Northeastern UniversityShenyang110819China

High ferrotitanium is used as a deoxidizer and alloying agent in steelmaking processes and is mainly produced using high-cost remelting *** thermite method is a simple and low-cost method for preparing low ***,the high levels of S,Al,and O residues in the product severely restrict its applicability in the low-cost preparation of good-quality high *** this study,a novel multistage deep reduction method for preparing high-quality high ferrotitanium is proposed,and the multistage desulfurization mechanism is systematically *** results indicate that multistage desulfurization is an effective method for reducing the S content of high ferrotitanium prepared via the thermite *** the strong desulfurization stage,Ti_(2)S reacts with CaO at the slag-metal interface and produces *** S content decreases,while the O content increases,with the increase of CaO in the CaO-Al_(2)O_(3)-based *** the deep desulfurization,Ti_(2)S is deeply reduced by the Ca and produces CaS,thus further reducing the S *** S content decreases with the incremental addition of Ca and can be reduced to 0.035 wt%after multistage desulfurization.

关键词： Multistage desulfurization High ferrotitanium Thermite method Multistage reduction Deep reduction

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Ordered Bicontinuous Network Structures Regulated by Orientational Interactions in a Rod-Coil Block Copolymer

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Chinese Journal of Polymer Science 2024年第5期42卷 636-642,I0008页

作者： Xiao-Lin Lyu Shi-chu Yang An-Qi Xiao Ping-Ping Hou Wei Zhang Hong-bing Pan zhi-Hao Shen Xing-He Fan Qi-Feng Zhou Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Key Laboratory of Advanced Materials Technologies International(HongKong Macao and Taiwan)Joint Laboratory on Advanced Materials TechnologiesCollege of Materials Science and EngineeringFuzhou UniversityFuzhou350108China

The rich phase behavior of block copolymers(BCPs)has drawn great attention in recent ***,the double diamond(DD)phase is rarely obtained because of the competition between the minimization of interfacial energy and packing ***,a rod-coil BCP containing mesogen-jacketed liquid crystalline polymer is designed to acquire ordered bicontinuous network *** reduction of internal energy originating from the orientational interaction among the rod blocks can compensate for the free energy penalty of packing frustration to stabilize the DD *** resulting BCP can also experience lamellae-to-DD and double gyroid-to-lamellae transitions by changing the annealing *** results make the rod-coil BCP an excellent candidate for the self-assembly of ordered network structures,demonstrating great potential in nanopatterning and metamaterials.

关键词： Block copolymer Rod-coil Ordered bicontinuous phase Double diamond Double gyroid

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Massive self-organized shape formation in grid environments

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Science China(Information Sciences) 2022年第6期65卷 256-257页

作者： Wenjie chu Wei ZHANG Haiyan ZHAO zhi JIN Hong MEI School of Computer Science Peking University Key Lab of High Confidence Software Technologies (Peking University) Ministry of Education Key Lab of High Confidence Software Technologies P(eking University) Ministry of Education

Self-organized shape formation can be observed in many natural processes [1, 2], involving crystallization, multi-cellular organism formation, and social insects collaboration. In these natural processes, complex stru... 详细信息

关键词： Shape Formation Self-Organization Artificial Light Field Multi-Agent Path Planning Collective Intelligence

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基于知识图谱增强的恶意代码分类方法

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郑州大学学报（理学版） 2025年第2期57卷 61-68页

作者：夏冰何取东刘文博楚世豪庞建民中原工学院前沿信息技术研究院河南郑州450007 河南省网络舆情监测与智能分析重点实验室河南郑州450007 数学工程与先进计算国家重点实验室河南郑州450001

针对应用程序接口(application programming interface,API)序列识别的恶意代码分类方法存在特征描述能力弱和调用关系缺失的问题,提出一种基于知识图谱增强的恶意代码分类方法。首先,基于函数调用图抽取恶意代码所含的API实体及其调用... 详细信息

针对应用程序接口(application programming interface,API)序列识别的恶意代码分类方法存在特征描述能力弱和调用关系缺失的问题,提出一种基于知识图谱增强的恶意代码分类方法。首先,基于函数调用图抽取恶意代码所含的API实体及其调用关系,在此基础上构建恶意代码API知识图谱。其次,使用Word2Vec技术计算携带上下文调用语义的API序列向量,借助TransE技术捕获API知识图谱中的API实体向量,将这两个向量的融合结果作为API特征。最后,将恶意代码所含的API表示为特征矩阵,输入TextCNN进行分类模型训练。在恶意代码家族分类任务中,与基线模型相比,所提方法的准确率有较大提升,达到93.8%,表明知识图谱可以有效增强恶意代码家族分类效果。同时,通过可解释性实验证实了所提方法具有应用价值。

关键词：恶意代码 API序列语义抽取知识图谱可解释性

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