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Structure and electrochemical performances of Mg20-xYxNi10（x=0-4） alloys prepared by mechanical milling

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Rare Metals 2019年第10期38卷 954-964页

作者： Yang-Huan Zhang Xi-ping song Pei-Long Zhang Yong-Guo Zhu Hui-ping Ren Bao-Wei Li Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Whole Win Materials Sci.&Tech.Co. Ltd.Beijing 100083Chin

Mg2Ni-type Mg20-xYxNi10(x=0,1,2,3 and4) electrode alloys were fabricated by vacuum induction ***,the as-cast alloys were mechanically milled on a planetary-type ball *** effects of milling time and Y content on the microstructures and electrochemical performances of the alloys were investigated in *** results show that nanocrystalline and amorphous structure can be successfully obtained through mechanical *** substitution of Y for Mg facilitates the glass forming of the Mg2Ni-type alloy and significantly enhances the electrochemical characteristics of the alloy ***,the discharge capacity of Y-free alloy monotonously grows with the milling time prolonging,while that of the Y-substituted alloys has the maximum values in the same *** milling time of obtaining the greatest discharge capacity markedly decreases with Y content *** electrochemical kinetics of the alloys,including high rate discharge ability(HRD),diffusion coefficient(D),limiting current density(IL) and charge transfer rate,monotonously increase with milling time extending.

关键词： Mg2Ni-type alloy Y substitution for Mg Milling duration Electrochemical performances

Rapid and non-destructive detection method for water status and water distribution of rice seeds with different vigor

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 231-238页

作者： ping song Ghiseok Kim Peng song Tao Yang Xia Yue Ying Gu College of Information and Electrical Engineering Shenyang Agricultural UniversityShenyang 110866China Liaoning Engineering Research Centre for Information Technology in Agricultural Shenyang Agricultural UniversityShenyang 110866China Department of Biosystems&Biomaterials Science and Engineering College of Agriculture&Life SciencesSeoul National UniversitySeoul 08826Korea College of Plant Science&Technology Huazhong Agricultural UniversityWuhan 430070China School of Information and Intelligence Engineering University of SanyaSanyaHainan 572022China Academician Workstation of Guoliang Chen University of SanyaSanyaHainan 572022China

In this study,newly harvested and aged rice seeds were analyzed to determine their aging process,identify the difference between artificially and naturally aged seeds,and develop a rapid,accurate,and non-destructive detection method for water status and water distribution of rice seed with different *** this end,an artificially accelerated aging test was conducted on the newly harvested rice ***,low-field nuclear magnetic resonance(LF-NMR)technology was applied to test the new(Shennong No.9816,2018),old(Shennong No.9816,2017),and artificially aged seeds(Shennong No.9816,2018).A standard germination test was conducted for three types of ***,the differences of water status and distribution between rice seeds of different vigor were analyzed based on the standard germination test results and wave spectrometry information collected using *** results indicated that new seeds,old seeds,and the artificially accelerated aging rice seeds all exhibited two water phases,and the vigor of rice seeds after the artificial accelerated aging test was lower than that of new *** were significant differences between the frequencies of bound water at the time of the peak and the time at the end of the peak for the three types of *** two times showed an increasing trend for rice seeds with poor vigor,indicating that the ability of the water in the rice seeds having poor vigor to combine with other substances was *** were significant differences between the distributions of free water peak end time for the three types of *** the rice seeds with poor vigor exhibited a decreasing trend at this time,indicating that the freedom of free water inside the rice seed samples with poor vigor was *** total water content of the artificially aged seeds and the aged seeds was higher than that of the new seeds,but the free water content increased from artificially aged seeds to new seeds to aged *** indicates that LF-NMR technol

关键词： low-field nuclear magnetic resonance rice seed water status detection water distribution detection seed vigor

Detection of rice seed vigor by low-field nuclear magnetic resonance

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International Journal of Agricultural and Biological Engineering 2018年第6期11卷 195-200页

作者： ping song Peng song Hongwei Yang Tao Yang Jing Xu Kaitian Wang College of Information and Electrical Engineering Shenyang Agricultural UniversityShenyang 110866China Beijing Research Center for Information Technology in Agriculture Beijing 10097China National Research Center of Intelligent Equipment for Agriculture Beijing 10097China

A new method to predict the seed vigor of rice was developed to control adulteration during the seed trading process and to address the deficiencies of traditional manual detection ***-field nuclear magnetic resonance(LF-NMR)technique was used to detect the vigor of rice *** varieties(Beijing-1,Qianchonglang-2,Yanfeng-47 and Shennong-265)of rice seeds from the Rice Research Institute of Shenyang Agricultural University were chosen for the *** transverse relaxation time T_(2),T_(21) and T_(22) were observed in the *** peak start time of free water(transverse relaxation time T_(22)),signal amplitude of bound water(transverse relaxation time T_(21)),and moisture content decreased with the decrease in the vigor of the *** were no obvious trends observed for the top of the peak and the end point of the transverse relaxation time T_(22).In addition,the start,top,and end time of the peak(transverse relaxation time T_(21)),and the signal amplitude of bound water showed no consistent *** results indicated that LF-NMR could be used as a method to distinguish the vigor of rice seeds *** study provided theoretical basis and technical support for the rapid detection of rice seed vigor.

关键词： nondestructive detection nuclear magnetic resonance transverse relaxation time signal amplitude rice seeds vigor

Hydrothermal Synthesis, Structural Characterization and Properties of Mixed Valent Decavanadium Oxide [Co_2Cl_8V_(10) O_(18)(H_2O)]Cl_2·6H_2O with Novel Three-dimensional Framework

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Chemical Research in Chinese Universities 2003年第2期19卷 135-139页

作者： WU ping song XU Lin WANG En bo HU Chang wen Faculty of Chemistry Northeast Normal UniversityChangchun 130024P.R.China

Decavanadium oxide [Co 2Cl 8V 10 O 18 (H 2O)]Cl 2·6H 2O was synthesized hydrothermally with NH 4VO 3, Na 2MoO 4·2H 2O, H 3PO 4(85%), CoCl 2·6H 2O and hexamethylenetetraamine. The X ray diffraction analysis showed that [Co 2Cl 8V 10 O 18 (H 2O)]Cl 2·6H 2O crystallized in a monoclinic crystal system, the space group was C2/m with cell parameters a =1 6065(3) nm, b =2 2699(5) nm, c =1 3897(3) nm, β = 125.29(3)°, V =4 1363(14) nm 3, Z =2 and the final R =0 06, wR =0 1926. Its crystal structure is a 3 D open framework constructed by VO x polyhedra and CoCl 4 tetrahedra with channels along the crystallographic axes a, b, and c .

关键词： Hydrothermal synthesis Polyoxometalate Crystal structure

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装液战斗部液体分散的数值仿真与试验研究

兵器装备工程学报 2024年第6期45卷 134-141页

作者：王振雄宋平郝焕明余留芳陆晓霞陈鹏军事科学院防化研究院北京102205

通过建立典型战斗部结构在不同驱动压力、不同动力黏度液体工况下的液体分散流体动力学仿真模型,对战斗部壳体的受力情况进行计算分析,仿真计算结果与试验测试数据对比可知,计算模型可为该装液战斗部壳体的受力规律分析提供支撑。建立... 详细信息

通过建立典型战斗部结构在不同驱动压力、不同动力黏度液体工况下的液体分散流体动力学仿真模型,对战斗部壳体的受力情况进行计算分析,仿真计算结果与试验测试数据对比可知,计算模型可为该装液战斗部壳体的受力规律分析提供支撑。建立了战斗部壳体内部压力测试系统,获得壳体内部轴向的不同部位的压力时程曲线和压力峰值,得出战斗部壳体内部由于压力波的叠加导致战斗部内部壳壁的峰值均高于驱动压力值,位于喷射孔近区的战斗部壳体承受压力值最大,随着与喷射孔距离的增加,压力峰值随之下降;火药产生的驱动压力和液体动力黏度与战斗部壳体的压力值均正相关。

关键词：战斗部设计黏弹性液体液体分散数值仿真试验研究

Effects of immunosuppressants after penetrating keratoplasty:meta-analysis of randomized controlled trials

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International Journal of Ophthalmology(English edition) 2011年第5期4卷 529-536页

作者： Xin Wei Xiao-Ming Chen Lin Wang Jin-ping song and Yin-ping Deng Department of Ophthalmology & Ophthalmic Laboratories West China Hospital Sichuan University Chengdu 610041 Sichuan Province China

AIM: To assess the effectiveness of immunosuppressants in the prophylaxis of corneal allograft rejection after high-risk keratoplasty and normal-risk keratoplasty. METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CNKI, VIP and reference lists of articles. Date of most recent search: 18 June, 2011. All randomised controlled trials (RCTs) assessing the use of immunosupressants in the prevention of graft rejection, irrespective of publication language. Two authors assessed trial quality and extracted data independently. Only dichotomous outcomes (clear graft survival, ratio of immune reactions and side effects) were available and were expressed as relative risk (RR) and 95% confidence intervals (CI). RESULTS: Seven studies were included in this review. In the comparing of mycophenolate mofetil (MMF) with placebo, the results showed MMF could significantly reduce immune reactions compared with placebo (RR 1.08 95% Cl 0.95 to 1.21), but no effect on clear graft survival (RR 1.11 95% Cl 0.90 to 1.35). In clear graft survival and immune reactions, MMF and cyclosporine A (CsA) showed similar effect (RR 1.11 95% Cl 0.90 to 1.35, and RR 1.48, 95% Cl 0.56 to 3.93, respectively). Tacrolimus (FK506) and steroid showed similar effects on clear graft survival and immune reactions (RR 0.32, 95% CI 0.02 to 6.21, and RR 1.00, 95%CI 0.88 to 1.14, respectively). No drug relative side effect has been found. CONCLUSION: MMF may reduce immune reactions in both normal-risk and high-risk rejection of penetrating keratoplasty. CsA and FK506 showed similar effects as MMF. However, due to the lack of large clinical trials, the evidence remain weak, the quality of evidences were rated as very low to moderate. Large, properly randomised, placebo-controlled, double masked trials are needed to evaluate the effect of immunosuppressants.

关键词： immunosuppressants penetrating keratoplasty meta-analysis

3D Shapeable,Superior Electrically Conductive Cellulose Nanofibers/Ti_(3)C_(2)T_(x) MXene Aerogels/Epoxy Nanocomposites for Promising EMI Shielding

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Research 2020年第1期2020卷 690-701页

作者： Lei Wang ping song Cheng-Te Lin Jie Kong Junwei Gu Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072China Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and Engineering(NIMTE)Chinese Academy of SciencesNingbo 315201China

In this work,3D highly electrically conductive cellulose nanofibers(CNF)/Ti_(3)C_(2)T_(x) MXene aerogels(CTA)with aligned porous structures are fabricated by directional freezing followed by freeze-drying technique,and the thermally annealed CTA(TCTA)/epoxy nanocomposites are then fabricated by thermal annealing of CTA,subsequent vacuum-assisted impregnation and curing *** show that TCTA/epoxy nanocomposites possess 3D highly conductive networks with ultralow percolation threshold of 0.20 vol%Ti_(3)C_(2)T_(x).When the volume fraction of Ti_(3)C_(2)T_(x) is 1.38 vol%,the electrical conductivity(σ),electromagnetic interference shielding effectiveness(EMI SE),and SE divided by thickness(SE/d)values of the TCTA/epoxy nanocomposites reach 1672 Sm-1,74 dB,and 37 dBmm-1,respectively,which are almost the highest values compared to those of polymer nanocomposites reported previously at the same filler *** addition,compared to those of the samples without Ti_(3)C_(2)T_(x),the storage modulus and heat-resistance index of TCTA/epoxy nanocomposites are enhanced to 9792.5 MPa and 310.7℃,increased by 62%and 6.9℃,respectively,presenting outstanding mechanical properties and thermal *** fabricated lightweight,easy-to-process,and shapeable TCTA/epoxy nanocomposites with superior EMI SE values,excellent mechanical properties,and thermal stabilities greatly broaden the applications of MXene-based polymer composites in the field of EMI shielding.

关键词： MXene composites fibers

Tensile properties of tungsten-rhenium wires with nanofibrous structure

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International Journal of Minerals,Metallurgy and Materials 2018年第9期25卷 1055-1059页

作者： Na-na Qiu Yin Zhang Cheng Zhang Huan Tong Xi-ping song State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

In this study, the mechanical properties of tungsten-rhenium wires with nanofibrous microstructure were investigated at both room temperature(RT) and 800?C. The strengthening mechanism associated to the nanofibrous microstructure was discussed. The results showed that the tungsten-rhenium wires with nanofibrous grains exhibited a very high tensile strength reaching values of 3.5 GPa and 4.4 GPa for the coarse(grains diameter of 240 nm) and fine(grains diameter of 80 nm) wires, respectively. With increasing the temperature from RT to 800?C, the tensile strength decreased slightly but still held high values(1.8 GPa and 3.8 GPa). All the fracture surfaces exhibited apparent necking and characteristics of spear-edge shaped fracture surface, indicating excellent ductility of the wires. A model of the strengthening mechanism of these tungsten-rhenium wires was proposed.

关键词： tungsten-rhenium wire mechanical properties nanofibrous microstructure tensile strength

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Neuroscience Bulletin 2017年第2期33卷 238-246页

作者： Rong Zhang Hong-Feng Zhang Ji-Sheng Han song-ping Han Neuroscience Research Institute Peking UniversityBeijing 100191China Department of Neurobiology School of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China Key Laboratory for Neuroscience Ministry of Education/National Health and Family Planning CommissionPeking UniversityBeijing 100191China Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of NeuroscienceCollege of MedicineXiamen UniversityXiamen 361005China

Autism spectrum disorder（ASD） is a highly heritable neurodevelopmental disorders characterized by impaired social interactions, communication de？cits, and repetitive behavior. Although the mechanisms underlying its etiology and manifestations are poorly understood,several lines of evidence from rodent and human studies suggest involvement of the evolutionarily highly-conserved oxytocin（OXT） and arginine-vasopressin（AVP）, as these neuropeptides modulate various aspects of mammalian social behavior. As far as we know, there is no comprehensive review of the roles of the OXT and AVP systems in the development of ASD from the genetic aspect. In this review, we summarize the current knowledge regarding associations between ASD and single-nucleotide variants of the human OXT-AVP pathway genes OXT, AVP, AVP receptor 1a（AVPR1a）, OXT receptor（OXTR）, theoxytocinase/vasopressinase（LNPEP）, and ADP-ribosyl cyclase（CD38）.

关键词： Oxytocin Arginine-vasopressin Singlenucleotide polymorphisms Autism spectrum disorder