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细颗粒等静压石墨结构调控及性能研究

炭素技术 2024年第3期43卷 41-46页

作者：连鹏飞赵俊通张俊鹏宋金亮刘犇赵红超刘占军中国科学院山西煤炭化学研究所山西太原030001 五星新材科技有限公司河南平顶山467000 中国科学院上海应用物理研究所上海201800 中国科学院大学北京100049

分别采用骨料/黏结剂二元法和中间相炭微球单相自烧结法制备了细颗粒等静压石墨。以煤沥青为黏结剂,平均粒径分别为10μm和5μm的沥青焦为骨料制备等静压石墨,标记为G1和G2;以平均粒径为5μm的中间相炭微球为原料,制备等静压石墨,标记... 详细信息

分别采用骨料/黏结剂二元法和中间相炭微球单相自烧结法制备了细颗粒等静压石墨。以煤沥青为黏结剂,平均粒径分别为10μm和5μm的沥青焦为骨料制备等静压石墨,标记为G1和G2;以平均粒径为5μm的中间相炭微球为原料,制备等静压石墨,标记为G3。研究了原料种类和颗粒尺寸对石墨材料微观结构、孔隙结构、晶体参数和热力学性能等的影响。骨料的粒径减小,能够有效地降低石墨材料结构内部的孔隙/缺陷尺寸,并提高材料的力学强度;G2石墨的平均孔径为0.527μm,远低于G1石墨的1.620μm,其抗折和抗压强度分别达到84MPa和142MPa。然而,较小的骨料粒径会降低石墨的结晶程度和晶粒尺寸,从而不利于其热性能的提升。采用平均粒径5μm的中间相炭微球试制的G3石墨具有非常优异的机械性能,抗折强度高达96MPa,平均孔径仅为0.071μm,而石墨化度和晶粒尺寸L_(a)分别为71.5%和38.8nm,石墨的常温热导率仅有47W/(m·K)。

关键词：细颗粒等静压石墨孔径分布微观结构热力学性能

Development of Ti_(0.85)Zr_(0.17)(Cr-Mn-V)_(1.3)Fe_(0.7)-based Laves phase alloys for thermal hydrogen compression at mild operating temperatures

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Rare Metals 2022年第8期41卷 2588-2594页

作者： Zi-Ming Cao Pan-Pan Zhou Xue-zhang Xiao liu-jun zhan Zhi-Fei Jiang Shu-Mao Wang Li-jun Jiang Li-Xin Chen State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Department of Materials Science and Engineering The University of ManchesterManchesterM139PLUK Institute of Energy Materials and Technology General Research Institute for Non-ferrous MetalsBeijing100088China Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province Hangzhou310013China

Metal hydride with proper hydrogen storage properties is the key component of hydride thermal hydrogen *** this work,Ti_(0.85)Zr_(0.17)(Cr-Mn-V)_(1.3)Fe_(0.7)-based alloys were developed to achieve thermal hydrogen compression at mild operating temperatures of water *** results indicate the single C 14-type Laves phase as well as homogeneously distributed elements of all *** increased Mn content in Ti_(0.85)Zr_(0.17)Cr_(1.2-x)Mn_xFe_(0.7)V_(0.1)(x=0,0.1,0.2,0.3)alloys.

关键词： alloys hydrogen Laves

Bursting behaviours in cascaded stimulated Brillouin scattering

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Chinese Physics B 2012年第1期21卷 310-313页

作者： liu zhan-jun He Xian-Tu Zheng Chun-Yang Wang Yu-Gang Institute of Applied Physics and Computational Mathematics Beijing 100094China State Key Laboratory of Nuclear Physics and Technology Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China

Stimulated Brillouin scattering is studied by numerically solving the Vlasov Maxwell system. A cascade of stim- ulated Brillouin scattering can occur when a linearly polarized laser pulse propagates in a plasma. It is found that a stimulated Brillouin scattering cascade can reduce the scattering and increase the transmission of light, as well as intro- duce a bursting behaviour in the evolution of the laser-plasma interaction. The bursting time in the reflectivity is found to be less than half the ion acoustic period. The ion temperature can affect the stimulated Brillouin scattering cascade, which can repeat several times at low ion temperatures and can be completely eliminated at high ion temperatures. For stimulated Brillouin scattering saturation, higher-harmonic generation and wave wave interaction of the excited ion acoustic waves can restrict the amplitude of the latter. In addition, stimulated Brillouin scattering cascade can restrict. the amplitude of the scattered light.

关键词： bursting behaviour stimulated Brillouin scattering cascade

Soil Quality Assessment of Acid Sulfate Paddy Soils with Different Productivities in Guangdong Province,China

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Journal of Integrative Agriculture 2014年第1期13卷 177-186页

作者： liu zhan-jun ZHOU Wei SHEN Jian-bo LI Shu-tian LIANG Guo-qing WANG Xiu-bin SUN Jing-wen AI Chao Key Laboratory of Plant Nutrition and Fertilization Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences College of Resources and Environmental Sciences China Agricultural University

Land conversion is considered an effective measure to ensure national food security in China, but little information is available on the quality of low productivity soils, in particular those in acid sulfate soil regions. In our study, acid sulfate paddy soils were divided into soils with high, medium and low levels based on local rice productivity, and 60 soil samples were collected for analysis. Twenty soil variables including physical, chemical and biochemical properties were determined. Those variables that were significantly different between the high, medium and low productivity soils were selected for principal component analysis, and microbial biomass carbon （MBC）, total nitrogen （TN）, available silicon （ASi）, pH and available zinc （AZn） were retained in the minimum data set （MDS）. After scoring the MDS variables, they were integrated to calculate a soil quality index （SQI）, and the high, medium and low productivity paddy soils received mean SQI scores of 0.95, 0.83 and 0.60, respectively. Low productivity paddy soils showed worse soil quality, and a large discrepancy was observed between the low and high productivity paddy soils. Lower MBC, TN, ASi, pH and available K （AK） were considered as the primary limiting factors. Additionally, all the soil samples collected were rich in available P and AZn, but deficient in AK and ASi. The results suggest that soil AK and ASi deficiencies were the main limiting factors for all the studied acid sulfate paddy soil regions. The application of K and Si on a national basis and other sustainable management approaches are suggested to improve rice productivity, especially for low productivity paddy soils. Our results indicated that there is a large potential for increasing productivity and producing more cereals in acid sulfate paddy soil regions.

关键词： soil quality assessment acid sulfate paddy soil soil quality index different productivity

Different responses of two adjacent artificial beaches to Typhoon Hato in Zhuhai,China

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Journal of Oceanology and Limnology 2024年第2期42卷 511-521页

作者： jun ZHU Qing WANG Chao zhan Fengjuan SUN Wenhao HUA Jianhui liu Hongshuai QI Yu YANG Coastal Research Institute Ludong UniversityYantai 264025China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 261005China

Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach(XL beach)and Meiliwan Beach(ML beach)in Zhuhai,China,were studied after Super Typhoon *** this study,a fully nonlinear Boussinesq wave model(FUNWAVE)-Total Variation Diminishing(TVD)was used to distinguish the main impact factors,their relative contributions,and the hydrodynamic mechanisms underlying the different beach *** show that compared to the ML beach,the main reason for the relatively weak erosion on Xiangluwan(XL)beach was the smaller beach berm height(accounting for approximately 75.9%of the erosion response).Regarding the beach with a higher berm,the stronger wave-induced undertow flow,along with the higher sediment concentration,led to a higher offshore sediment transport flux,resulting in more severe erosion relative to the beach with a smaller berm *** second most important reason explaining the weak erosion on XL beach was the absence of seawalls(accounting for approximately 17.9%of the erosion response).Wave reflection induced by the seawall could cause higher suspended sediment concentration,resulting in a toe scouring near the *** offshore submerged breakwater protected XL beach slightly(accounting for approximately 6.1%of the erosion response).Due to the higher water level induced by storm surge,most of the wave energy could penetrate through the submerged *** effect of the larger berm width of XL beach was *** to the beach with a larger berm width,the erosion/deposition regions in the beach with a narrower berm width showed shoreward migration,without significant changes in the erosion/deposition *** of this,the larger berm width could reduce the wave energy reaching the *** study of the storm stability of artificial beaches may be applied to beach restoration design.

关键词： beach erosion berm height berm width seawall fully nonlinear Boussinesq wave model(FUNWAVE)

Engineering the future cereal crops with big biological data:toward intelligence-driven breeding by design

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Journal of Genetics and Genomics 2024年第8期51卷 781-789页

作者： Lei liu Jimin zhan Jianbing Yan National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubei 430070China

How to feed 10 billion human populations is one of the challenges that need to be addressed in the following decades,especially under an unpredicted climate *** breeding,initiating from the phenotype-based selection by local farmers and developing into current biotechnology-based breeding,has played a critical role in securing the global food ***,regarding the changing environment and ever-increasing human population,can we breed outstanding crop varieties fast enough to achieve high productivity,good quality,and widespread adaptability?This review outlines the recent achievements in understanding cereal crop breeding,including the current knowledge about crop agronomic traits,newly developed techniques,crop big biological data research,and the possibility of integrating them for intelligence-driven breeding by design,which ushers in a new era of crop breeding practice and shapes the novel architecture of future *** review focuses on the major cereal crops,including rice,maize,and wheat,to explain how intelligence-driven breeding by design is becoming a reality.

关键词： Crop Big biological data Multi-omic Artificial intelligence Crop design breeding

Single-shot phase retrieval for randomly fluctuated and obstructed vortex beams

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 72-80页

作者： Hao zhang jun’an Zhu Xingyuan Lu Zhiquan Hu Jianbo Gao Kun liu Qiwen zhan Yangjian Cai Chengliang Zhao School of Physical Science and Technology Soochow UniversitySuzhou 215006China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shandong Provincial Engineering and Technical Center of Light Manipulations Shandong Provincial Key Laboratory of Optics and Photonic DeviceSchool of Physics and ElectronicsShandong Normal UniversityJinan 250358China Joint Research Center of Light Manipulation Science and Photonic Integrated Chip of East China Normal University and Shandong Normal University East China Normal UniversityShanghai 200241China

Vortex beams with orbital angular momentum play a crucial role in increasing the information capacity in optical *** magnitude of orbital angular momentum determines the ability of information *** practice,a vortex beam can encounter random objects or turbulence during free-space propagation,resulting in information ***,accurately measuring the orbital angular momentum of a randomly fluctuated and obstructed vortex beam is a considerable ***,we propose a single-shot method for the phase retrieval of a randomly fluctuated and obstructed vortex beam by combining the phase-shift theorem and self-reference *** results reveal that the sign and magnitude of the initial orbital angular momentum can be simultaneously determined based on their quantitative relation with the number of coherence singularities on the observation plane,thus addressing the effects of random occlusion and atmospheric *** proposed method considerably improved the accurate decoding of orbital angular momentum information in nonideal freespace optical communications.

关键词： optical vortex phase retrieve orbital angular momentum measurement antiturbulence antidisturbance

BMSC-derived Exosomes Ameliorate Peritoneal Dialysis-associated Peritoneal Fibrosis via the Mir-27a-3p/TP53 Pathway

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Current Medical Science 2024年第2期44卷 333-345页

作者： jun-li ZHAO Lin ZHAO Qiu-nan zhan Miao liu Ting zhanG Wen-wen CHU Department of Nephrology Shanghai University of Medicine&Health Sciences Affiliated Zhoupu HospitalShanghai 201318China Orthopedic Department Guangming Traditional Chinese Medicine Hospital of Pudong New AreaShanghai 201399China

Objective:Peritoneal fibrosis(PF)is the main cause of declining efficiency and ultrafiltration failure of the peritoneum,which restricts the long-term application of peritoneal dialysis(PD).This study aimed to investigate the therapeutic effects and mechanisms of bone marrow mesenchymal stem cells-derived exosomes(BMSC-Exos)on PF in response to ***:Small RNA sequencing analysis of BMSC-Exos was performed by second-generation sequencing.C57BL/6J mice were infused with 4.25%glucose-based peritoneal dialysis fluid(PDF)for 6 consecutive weeks to establish a PF model.A total of 36 mice were randomly divided into 6 groups:control group,1.5%PDF group,2.5%PDF group,4.25%PDF group,BMSC-Exos treatment group,and BMSC-Exos+TP53 treatment *** transcription quantitative polymerase chain reaction(RT-qPCR)was performed to measure the expression level of miR-27a-3p in BMSC-Exos and peritoneum of mice treated with different concentrations of *** and Masson staining were performed to evaluate the extent of *** therapeutic potential of BMSC-Exos for PF was examined through pathological examination,RT-qPCR,Western blotting,and peritoneal function ***-mesenchymal transition(EMT)of HMrSV5 was induced with 4.25%*** were divided into control group,4.25%PDF group,BMSC-Exos treatment group,and BMSC-Exos+TP53 treatment *** Counting Kit-8 assay was used to measure cell viability,and transwell migration assay was used to verify the capacity of BMSC-Exos to inhibit EMT in HMrSV5 ***:Small RNA sequencing analysis showed that miR-27a-3p was highly expressed in BMSC-derived exosomes compared to *** RT-qPCR results showed that the expression of miR-27a-3p was upregulated in BMSC-Exos,but decreased in PD *** found that PF was glucose concentration-dependently enhanced in the peritoneum of the PD *** with the control mice,the PD mice showed high solute transport and decreased ultrafiltration volume as well as an obvious f

关键词： peritoneal fibrosis bone marrow mesenchymal stem cell-derived exosomes miR-27a-3p TP53 epithelialmesenchymal transition

Dislocation density-me diate d creep ageing behavior of an Al-Cu-Li alloy

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Journal of Materials Science & Technology 2024年第7期174卷 204-217页

作者： Chang Zhou Lihua zhan Chunhui liu Minghui Huang College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China Light Alloys Research Institute Central South UniversityChangsha 410083China

Creep aging is well-known to be a time-dependent,coupled process of deformation and precipitation strengthening for age-hardening *** existing mechanisms are mainly attributed to those interac-tions between atomic diffusion and dislocation ***,an understanding of the relationship between dislocation density and a special multistage creep behavior,i.e.,double steady creep feature,is still far *** we investigate the effect of various dislocation density levels on such an abnormal multistage creep of an Al-Cu-Li *** find that the increased dislocation densities enable an apparent time decrease(from 6.2 h to 0.8 h)of their first steadyⅡ-*** yield strength of post-aged sam-ples increases from 425.0 MPa to 580.0 MPa while the corresponding elongation decreases from 12.3%to 7.3%for the creep-aged samples#1 to#*** results also reveal that a great difference in dislocation configuration,tailored by various density levels,results in varying creep processes of theⅡ-*** stage is closely related to the nucleation and early growth of T_(1)*** number densities(maximum:2.9×10^(19)m^(-3))and the average length(maximum:21.3 nm)of T_(1)precipitates are much smaller than those of the stable peak-aged T_(1)phases,suggesting that creepⅡ-stage of all three creep-aged samples is dominant by the nucleation and initial growth of those T_(1)*** study provides valuable insights into the dislocation density-mediated creep deformation of an Al-Cu-Li alloy.

关键词： Dislocation density Al-Cu-Li alloy Creep ageing T_(1)precipitation