检索结果-南通市图书馆

Chemical research in Chinese Universities 2008年第5期24卷 640-643页

作者： ZHANG Cheng-wu HUANG Yu-dong WANG Sheng-chao ZHANG Chun-yu ZHANG Xue-quan Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 P. R. China heilongjiang provincial plastics industry scientific research institute Harbin 150001 P R. China Changchun institute of Applied Chemistry Chinese Academy of Sciences Changehun 130022 P. R. China

Morphologies,crystallization behavior and mechanical properties of polypropylene（PP）/syndiotactic 1,2-polybutadiene（s-1,2 PB）blends were *** observation shows the well dispersed domains of s-1,2 PB in PP matrix with the rather small domain sizes from 0.1 to 0.5μm when the s-1,2 PB content increases from 5%to 20%（mass fraction）in the blends,and the phase structure tends to become co-continuous as s-1,2 PB content further *** temperature（Tc）of PP component in the blends is fluctuated with the variation of s-1,2 PB content in the ***,to some extent,between the two components is inferred from the examination of both morphology and crystallization *** of impact strength of PP toughened by s-1,2 PB becomes significant only in the case of s-1,2 PB content above 20%（mass fraction）.

关键词： Syndiotactic 1,2-polybutadiene Polypropylene Crystallization SEM DSC

Correlation analysis of longitudinal cracks and vertical deformation within asphalt pavement of cold regions

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research in Cold and Arid Regions 2023年第6期15卷 278-287页

作者： Ke Chen Lun Ji ZeYu Xiao JinQi Wu LinLin Xu ZhiCe Cheng heilongjiang provincial Highway Survey and Design institute HarbinHeilongjiang 150080China School of Traffic Science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150090China heilongjiang Highway Construction Center HarbinHeilongjiang 150090China

The asphalt pavement longitudinal crack is a common distress in cold regions,resulting from uneven deformation of the *** of the correlation law between uneven deformation and crack distress is of positive significance for understanding the mechanism of crack initiation,and putting forward treatment *** view of the complexity of longitudinal crack inducement and road surface deformation,the grey relational method was used to analyze this *** long-term monitoring of the vertical deformation data of typical road sections,the vertical deformation law of the pavement surface and its deformation characteristics under the action of temperature field are *** such as vertical relative deformation,vertical relative deformation rate and vertical differential deformation VDSr were constructed to describe vertical deformation *** distribution characteristics of longitudinal fractures and their length and distribution characteristics are also *** grey correlation analysis theory was utilized to analyze the relationship between deformation characteristics of sections,cross sections and monitoring points and longitudinal crack characteristics(length and location).The analysis reveals a linear positive correlation or a high correlation between several *** study can provide a deeper understanding of the occurrence and development mechanism of longitudinal cracks in asphalt pavement of cold areas,and give references for the research of road engineering structure,materials and distress prevention.

关键词： Asphalt pavement Cold region Longitudinal crack Vertical deformation Grey relational analysis

Fabrication and wear properties of co-deposited Ni-Cr nanocomposite coatings

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中国有色金属学会会刊：英文版 2010年第1期20卷 104-109页

作者：周月波赵国刚张海军 College of Materials Science and Engineering Heilongjiang Institute of Science and Technology

Ni-Cr nanocomposite coatings with different Cr particles contents were developed by electrodeposition method from a nickel sulfate solution containing different concentrations of Cr nanoparticle with an average particle size of 40 nm. The characteristics of the coatings were assessed by scanning electron microscopy and microhardness test. The friction and wear performances of Ni-Cr nanocomposite coatings and pure Ni film were comparatively investigated, with the effect of the Cr content on the friction and wear behaviors to be emphasized. The results indicate the microhardness, friction and wear behaviors of Ni-Cr nanocomposite coatings are closely related with Cr particles content. The Ni-Cr nanocomposite coating with a lower Cr content of 4.0% shows somewhat increased microhardness and wear resistance than the pure Ni coating, while the Ni-Cr nanocomposite coating with a higher Cr content has much better wear resistance than the pure Ni coating. The effect of Cr nanoparticles on the microhardness and wear resistance was discussed.

关键词：纳米复合涂层摩擦磨损行为镍铬涂层性能扫描电子显微镜硬度测试沉积制备

Sliding wear behaviors of electrodeposited Ni composite coatings containing micrometer and nanometer Cr particles

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中国有色金属学会会刊：英文版 2009年第2期19卷 319-323页

作者：赵国刚周月波张海军 College of Materials Science and Engineering Heilongjiang Institute of Science and Technology

Micrometer and nanometer Cr particles were co-deposited with Ni by electroplating from a nickel sulfate bath containing a certain content of Cr particles. Cr microparticles are in a size range of 1-5 μm and Cr nanoparticles have an average size of 40 nm. The friction and the wear performance of the co-deposited Ni-Cr composite coatings were comparatively evaluated by sliding against Si3N4 ceramic balls under non-lubricated conditions. It is found that the incorporation of Cr particles enhances the microhardness and wear resistance of Ni coatings. The wear resistance of Ni composite coating containing Cr nanoparticles is higher than that of the Ni composite coating containing Cr microparticles with a comparable Cr particle content. The co-deposition of smaller nanometer Cr particles with Ni effectively reduces the size of Ni crystals and significantly increases the hardness of the composite coatings due to grain-refinement strengthening and dispersion-strengthening,resulting in a significant improvement of wear resistance of the Ni-Cr nanocomposite coatings.

关键词：纳米粒子复合涂层电沉积镍铬磨损行为微米滑动 Si3N4陶瓷球

Germinated brown rice relieves hyperlipidemia by alleviating gut microbiota dysbiosis

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Journal of Integrative Agriculture 2023年第3期22卷 945-957页

作者： REN Chuan-ying ZHANG Shan HONG Bin GUAN Li-jun HUANG Wen-gong FENG Jun-ran SHA Di-xin YUAN Di LI Bo JI Ni-na LIU Wei LU Shu-wen Food Processing research institute Heilongjiang Academy of Agricultural SciencesHarbin 150086P.R.China heilongjiang Province Key Laboratory of Food Processing Harbin 150086P.R.China Safety and Quality institute of Agricultural Products Heilongjiang Academy of Agricultural SciencesHarbin 150086P.R.China Soybean research institute Heilongjiang Academy of Agricultural SciencesHarbin 150086P.R.China The Second Affiliated Hospital Harbin Medical UniversityHarbin 150086P.R.China

Hyperlipidemia is a frequent metabolic disorder that is closely associated with diet. It is believed that brown rice, containing the outer bran layer and germ, is beneficial for the remission of hyperlipidemia. This study established a rat model of hyperlipidemia by feeding a high-fat diet. The hypolipidemic potential of germinated brown rice(Gbrown) and germinated black rice(a germinated black-pigmented brown rice, Gblack) were explored in the model rats, mainly in the aspects of blood lipids, lipases, apolipoproteins, and inflammation. The gut microbiota in hyperlipidemic rats receiving diverse dietary interventions was determined by 16S rDNA sequencing. The results showed that the intervention of Gbrown/Gblack alleviated the hyperlipidemia in rats, evidenced by decreased TC, TG, LDL-C, and apolipoprotein B, and increased HDL-C, HL, LPL, LCAT, and apolipoprotein A1. Gbrown/Gblack also weakened the inflammation in hyperlipidemia rats, evidenced by decreased TNF-α, IL-6, and ET-1. In addition, 16S rDNA sequencing revealed that the diet of Gbrown/Gblack elevated the abundance and diversity of gut microbiota in hyperlipidemia rats. At the phylum level, Gbrown/Gblack decreased Firmicutes, increased Bacteroidetes, and decreased the F/B ratio in hyperlipidemia rats. At the genus level, Gbrown/Gblack decreased Streptococcus and increased Ruminococcus and Allobaculum in hyperlipidemia rats. Some differential microbial genera relating to lipid metabolism were also determined, such as the Lachnospira and Ruminococcus in the Gblack group, and the Phascolarctobacterium, Dorea, Turicibacter, and Escherichia-Shigella in the Gbrown group. Notably, the beneficial effect of Gblack was stronger than Gbrown. To sum up, the dietary interventions of Gbrown/Gblack contributed to the remission of hyperlipidemia by alleviating the dysbiosis of gut microbiota.

关键词： hyperlipidemia germination brown rice black rice gut microbiota

Water regime-nitrogen fertilizer incorporation interaction：Field study on methane and nitrous oxide emissions from a rice agroecosystem in Harbin, China

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Journal of Environmental Sciences 2018年第2期30卷 289-297页

作者： Wenjun Dong Jia Guo Lijun Xu Zhifeng Song Jun Zhang Ao Tang Xijuan Zhang Chunxu Leng Youhong Liu Lianmin Wang Lizhi Wang Yang Yu Zhongliang Yang Yilei Yu Ying Meng Yongcai Lai heilongjiang Academy of Agricultural Sciences Postdoctoral Programme Harbin 150086 China Cultivation and Farming research institute Heilongjiang Academy of Agricultural Sciences Harbin 150086 China Northern Japonica Rice Molecular Breeding Joint research Center Chinese Academy of Sciences Harbin 250086 China scientific Observing and Experimental Station of Crop Cultivation in Northeast China Ministry of Agriculture Harbin 150086 China institute of Wetland research Chinese Academy of Forestry Beijing 100091 China Beijing Key Laboratory of Wetland Services and Restoration Beijing 100091 China institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Jilin Academy of Agricultural Sciences ChangchunJilin 130124 China institute of Crop Science Chinese Academy of Agricultural Sciences Beijing 100081 China Rice institute of Wuchang Heilongjiang Academy of Agricultural Sciences Wuchang 150229 China

Water regime and nitrogen（N） fertilizer are two important factors impacting greenhouse gases（GHG） emission from paddy field, whereas their effects have not been well studied in cold region. In this study, we conducted a two-year field experiment to study the impacts of water regime and N fertilizer on rice yields and GHG emissions in Harbin, China, a cold region located in high latitudes. Our results showed that intermittent irrigation significantly decreased methane（CH4） emission compared with continuous flooding, however,the decrement was far lower than the global average level. The N2O emissions were very small when flooded but peaked at the beginning of the disappearance of floodwater. The N fertilizer treatments increased CH4 emissions at low level（75 kg N/ha）. But both CH4 and N2O emissions were uninfluenced at the levels of 150 kg N/ha and 225 kg N/ha. Rice yields increased under intermittent irrigation and were highest at the level of 150 kg N/ha. From our results, we recommended that the intermittent irrigation and 150 kg N/ha as the ideal water regime-nitrogen fertilizer incorporation for this area to achieve low GHG emissions without impacting rice yields.

关键词： Methane(CH4) Nitrous oxide(N2O) Rice ecosystem Cold region Global warming potential

Baicalin inhibits colistin sulfate-induced apoptosis of PC12 cells

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Neural Regeneration research 2013年第28期8卷 2597-2604页

作者： Hong Jiang Pengfei Lv Jichang Li Hongjun Wang Tiezhong Zhou Yingzi Liu Wei Lin institute of Veterinary Medicine Northeast Agricultural University institute of Animal Husbandry and Veterinary Medicine Liaoning Medical University scientific research Department Liaoning Medical Universit

Baicalin, a type of flavonoid extracted from the dried root of Scutellaria baicalensis georgi, has been shown to effectively inhibit cell apoptosis. Therefore, we assumed that baicalin would suppress colistin sulfate-induced neuronal apoptosis. PC12 cells exposed to colistin sulfate （62.5-500 μg/mL） for 24 hours resulted in PCl2 cell apoptosis. In addition, caspase-3 activity, lactate dehydrogenase level and free radical content increased in a dose-dependent manner. Subsequently, PC12 cells were pretreated with baicalin （25, 50 and 100 pg/mL）, and exposed to 125 pg/mL colistin sulfate. Cell morphology markedly changed, and cell viability increased. Moreover, caspase-3 activity, lac- tate dehydrogenase level and free radical content decreased. Results indicated that baicalin inhib- ited colistin sulfate-induced PC12 cell apoptosis by suppressing free radical injury, and reducing caspase-3 activity and lactate dehydrogenase activity.

关键词： neural regeneration traditional Chinese medicine baicalin colistin sulfate PC12 cells apoptosis caspase-3 lactate dehydrogenase grants-supported paper neuroregeneration

Conceptual design of the tail research experiment at the Space Plasma Environment research Facility(SPERF-TREX)

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Plasma Science and Technology 2024年第8期26卷 44-49页

作者：肖青梅毛傲华何向磊邹继同杨肖易孙萌萌李丰汤鹏飞周田春王晓钢 the SPERF Team Laboratory for Space Environment and Physical Sciences Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Physics Harbin Institute of TechnologyHarbin 150001People’s Republic of China heilongjiang provincial Key Laboratory of Plasma Physics and Application Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

The Space Plasma Environment research Facility(SPERF)for ground simulation of the space plasma environment is a key component of the Space Environment Simulation research Infrastructure(SESRI),a major national science and technology infrastructure for fundamental *** is designed to investigate outstanding issues in the space plasma environment,such as energetic particle acceleration,transport,and interaction with electromagnetic waves,as well as magnetic reconnection processes,in magnetospheric *** Tail-research EXperiment(TREX)is part of the SPERF for laboratory studies of space physics relevant to magnetic reconnection,dipolarization and hydromagnetic wave excitation in the *** is designed to carry out three types of experiments:the tail plasmoid for magnetic reconnection,dipolarization front formation,and magnetohydrodynamic waves excited by highspeed plasma *** this paper,the scientific goals and three scenarios of SPERF-TREX for typical processes in space plasmas are presented,and experimental plans for SPERF-TREX are also reviewed,together with the plasma sources applied to generate the plasma with the desired parameters and various magnetic configurations.

关键词： SPERF-TREX wave-particle interaction magnetic reconnection dipolarization

Characterization of chaotic and periodic dynamics in a time series

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Journal of Harbin institute of Technology(New Series) 2011年第2期18卷 67-70页

作者：谢忠玉王科俊张旺 College of Automation Harbin Engineering University Dept. of Electronic Engineering Heilongjiang Institute of Technology research Centre for Space Optical Engineering Harbin Institute of Technology

In order to characterize synthesizing periodic and chaotic component dynamics in a time series, classical chaotic system-logistic map and Duffing system was examined by time dependent exponent (TDE) of the direct dynamical test. The simulative calculation results with the logistic map and Duffing system showed that periods and chaotic dynamics can be readily characterized by computing a series of TDE curves. The method was also applied to study power short-term load time series as well as measured a time series. Their dynamic characteristics of chaotic component and period were conveniently found.

关键词： chaos period time dependent exponent

Sine-Gordon Solitons and Breathers in Rod-like Magnetic Liquid Crystals under External Magnetic Field

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Communications in Theoretical Physics 2018年第12期69卷 759-764页

作者： Yan Li Xiao-Bo Lu Chun-Feng Hou Department of Physics Harbin Institute of Technology Department of Physics Science and Technology Heilongjiang University

To study the nonlinear phenomena in rod-like magnetic liquid crystals(RMLCs), this paper establishes the dynamic model of molecular motion when giving a twisting disturbance to the molecules under external magnetic *** find the twist of the molecules under magnetic field can be propagated in the form of a traveling wave. The dynamic equation of the molecular twisting we derived satisfies the form of Sine-Gordon equation. We obtain two solutions of the Sine-Gordon equation by theoretical calculation: the kink and anti-kink solitons and breathers. The characteristics of those solitons and breathers are discussed.

关键词： rod-like magnetic liquid crystals Sine-Gordon equation kink and anti-kink solitons breathers