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Preparation of hollow ceramic microspheres absorbent based on self-reactive quenching technology

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Rare Metals 2015年第5期34卷 344-350页

作者： Jian-Jiang Wang Hong-Fei Lou Jin-Hua Wen xu-Dong cai Advanced Materials Institute Mechanical Engineering College

A1 ＋ BaO2 ＋ Fe2O3 ＋ sucrose and O2 as reaction system and feeding gas, respectively, are used to prepare hollow multiphase ceramic microspheres （HMCMs） absorbent based on self-reactive quenching technology. The morphologies, particle size distribution, hollow structure and phase compositions were characterized by scanning electron microscope （SEM）, X-ray diffraction （XRD） and size analysis. The results show that the quenching products possess high sphere-forming rate, and most of them are hollow structures. Owing to the self-burst, the particle size is between 40 and 70 μm. The phase compositions contain Al2O3, Fe3O4, Fe2O3, Ba2Fe14O22, BaO2 and BaFe4O7. The microwave absorbing tests show that the lowest reflectivity of HMCMs is -19 dB. The frequency bands less than -10 dB are from 13.0 to 15.8 GHz. The reasons for HMCMs possessing good microwave absorbing properties may be their magnetic and electrical properties as well as special hollow structure.

关键词： Self-reactive quenching technology Hollow multiphase ceramic microspheres Microwave absorbing properties

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考虑负荷特性与工况的公交充电站光储配置

计算机仿真 2024年第6期41卷 180-185,231页

作者：何鑫孙国歧魏晓宾蔡旭东华大学信息科学与技术学院上海201620 山东德佑电气股份有限公司山东淄博255088 上海交通大学电子信息与电气工程学院上海200240

随着光储充一体化充电站的发展,如何在现有公交充电站基础上合理确定光储容量成为了焦点。因此提出了考虑负荷特性与运行工况的光储公交充电站容量配置模型。首先考虑公交充电站充电负荷特性,通过移动边界法确定储能充放电状态的阈值,... 详细信息

随着光储充一体化充电站的发展,如何在现有公交充电站基础上合理确定光储容量成为了焦点。因此提出了考虑负荷特性与运行工况的光储公交充电站容量配置模型。首先考虑公交充电站充电负荷特性,通过移动边界法确定储能充放电状态的阈值,构建更加最优的光储公交充电站运行工况及运行条件。其次,以极大化光伏利用率和极小化系统投资、运行成本为目标,采用粒子群算法进行优化求解,确定出光储公交充电站最优的光伏以及储能容量。基于实际运营数据,对考虑负荷特性和运行工况的光储公交充电站和未考虑的光储公交充电站进行经济性对比。结果表明,在相同配置情况下考虑负荷特性和运行工况能够得到更加合理地光伏和储能容量。

关键词：电动公交光储电动公交充电站粒子群算法移动边界法

Texture and stretch formability of rolled Mg–Zn–RE(Y, Ce, and Gd) alloys at room temperature

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Rare Metals 2013年第5期32卷 441-447页

作者： Zheng-xu cai Hai-Tao Jiang Di Tang Zhao Ma Qiang Kang National Engineering Research Center of Advanced Rolling University of Science and Technology Beijing

To develop a new magnesium alloy with excellent formability at room temperature, the effect of Y, Ce, and Gd addition on texture and stretch formability of Mg-1.5Zn alloys was carried out. The result shows that Y, Ce, and Gd addition in Mg-1.5Zn alloys can effectively weaken and modify the basal plane texture, characterized by TD-split texture in which the position of basal is titled from normal direction （ND） toward transverse direction （TD）. When Mg-1.5Zn alloy with Gd addition appears low texture intensity and TD-split texture, where the position of basal poles is tilted by about 4-35° from ND toward to TD, the largest Erichsen value of 7.0 and the elongation rate reaches 29.1% in TD direction. However, Y and Ce addition in Mg-1.5Zn alloys promote a large number of second phase particles, which cancel the contribution of the unique basal texture to stretch formability and ductility.

关键词： Magnesium Texture Size effects Stretch formability Mechanical property Rare earth elements

Synthesis and Characterization of a HydrophilicHydrophobic IPN Composed of Poly(vinyl alcohol)and Polystyrene

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Chinese Chemical Letters 2005年第12期16卷 1597-1599页

作者： Yi Zhen TAN Man cai xu Hai Tao LI College of Chemistry and Chemical Engineering Hunan Normal University Changsha 410081

A hydrophilic/hydrophobic interpenetrating polymer network （IPN） of poly （vinyl alcohol） / polystyrene was prepared by conversion of the IPN of poly （vinyl acetate）/polystyrene. The hydrophilic/hydrophobic IPN w... 详细信息

关键词： Hydrophilic/hydrophobic interpenetrating polymer network poly(vinyl alcohol) polystyrene

ZL205A合金侧盖壳体铸造工艺研究与产品试制

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铸造 2024年第6期73卷 865-871页

作者：马文龙杨力杨小冬徐远财罗辉樊自田唐锦球江麓机电集团有限公司湖南湘潭411100 华中科技大学材料成形与模具技术全国重点实验室湖北武汉430000

模拟分析了重力铸造与低压铸造方法下ZL205A合金侧盖壳体铸件的充型、凝固过程及缺陷特征,进行了侧盖壳体铸件试制及性能对比。采用重力铸造时,模拟显示铸件充型速度快,紊流、混流现象严重,凝固速率慢且过程混乱,孔隙率高;样件表面及内... 详细信息

模拟分析了重力铸造与低压铸造方法下ZL205A合金侧盖壳体铸件的充型、凝固过程及缺陷特征,进行了侧盖壳体铸件试制及性能对比。采用重力铸造时,模拟显示铸件充型速度快,紊流、混流现象严重,凝固速率慢且过程混乱,孔隙率高;样件表面及内部缩松、偏析等缺陷严重,基体组织及晶界中微观缩松与成分偏析交织显现。取样部位平均抗拉强度与伸长率为A区:400 MPa,3.1%,B区:444 MPa,3.4%,铸件为不合格品。采用低压铸造时,模拟显示铸件充型平稳,凝固速率快且自上而下顺序凝固,孔隙率低,样件探伤合格,组织均匀致密且微观缩松和偏析占比显著降低。取样部位平均抗拉强度与伸长率为A区:478 MPa,4.7%,B区:484 MPa,4.9%,铸件合格且性能优异。验证了低压铸造工艺对ZL205A合金侧盖壳体铸件的适应性与优势。

关键词： ZL205A 铸造侧盖壳体组织结构力学性能

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On Multiplicity Difference Correlators in Second-Order Quark-Gluon Plasma Phase Transition

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Chinese Physics Letters 1999年第4期16卷 253-255页

作者： YAN Wen-biao YANG Chun-bin cai xu Institute of Particle Physics Huazhong Normal UniversityWuhan 430079 Institut für Theoretische Physik Freie Universität Berlin14195 BerlinGermany

The multiplicity difference correlators between two well-separated bins are studied in second-order quark-gluon plasma(QGP)phase transition within the Ginzburg-Landau *** the case with very low mean multiplicities,an exponentγis found,which has very weak dependence on the parameters of the model and can be used as a signal for the formation of QGP in ultra-relativistic heavy-ion collisions.

关键词： Transition exponent quark

竖脊肌平面阻滞与局部浸润麻醉对老年PKP手术患者镇痛效果、应激反应和炎症反应的影响

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现代生物医学进展 2024年第16期24卷 3143-3147页

作者：徐涛吴刚吴绪才徐敏燕黄良库石川西安交通大学医学院附属红会医院手术麻醉科陕西西安710001 西安交通大学医学院附属红会医院骨科陕西西安710001

目的:观察竖脊肌平面阻滞(ESPB)与局部浸润麻醉对老年球囊扩张椎体后凸成形术(PKP)手术患者镇痛效果、应激反应和炎症反应的影响。方法:选取2020年4月~2023年4月期间我院收治的110例老年PKP手术患者。根据随机数字表法,将患者分为对照组... 详细信息

目的:观察竖脊肌平面阻滞(ESPB)与局部浸润麻醉对老年球囊扩张椎体后凸成形术(PKP)手术患者镇痛效果、应激反应和炎症反应的影响。方法:选取2020年4月~2023年4月期间我院收治的110例老年PKP手术患者。根据随机数字表法,将患者分为对照组(接受局部浸润麻醉)、实验组(接受ESPB),各55例。对比两组血流动力学、疼痛视觉模拟评分(VAS)、应激反应和炎症反应情况,同时观察两组不良反应发生情况。结果:穿刺时(T1)~手术结束出室前(T4)时间点,两组平均动脉压(MAP)、心率(HR)先升高后下降,实验组低于同期的对照组(P0.05)。结论:与局部浸润麻醉相比,ESPB可更好的控制老年PKP手术患者血流动力学稳定,减轻应激反应和炎症反应,发挥良好的镇痛效果。

关键词：竖脊肌平面阻滞局部浸润麻醉老年 PKP 镇痛效果应激反应炎症反应

Slight shading after anthesis increases photosynthetic productivity and grain yield of winter wheat (Triticum aestivum L.) due to the delaying of leaf senescence

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Journal of Integrative Agriculture 2016年第1期15卷 63-75页

作者： xu cai-long TAO Hong-bin WANG Pu WANG Zhen-lin College of Agriculture and Biotechnology China Agricultural University National Key Laboratory of Crop Biology Agronomy College Shandong Agricultural University

The solar radiation intensity and duration are continuously decreasing in the major wheat planting area of China. As a con- sequence, leaf senescence, photosynthesis, grain filling and thus wheat yield shall be affected by light deficiency. Therefore, two winter wheat （Triticum aestivum L.） cultivars, Tainong 18 （a large-spike cultivar） and Ji＇nan 17 （a multiple-spike cultivar）, were subjected to shading during anthesis and maturity under field condition in 2010-2011 and 2011-2012. Under the slight shading treatment （$1,88% of full sunshine）, leaf senescence was delayed, net photosynthesis rate （Po） and canopy apparent photosynthesis rate （CAP） were improved, and thus thousand-kernel weight （TKW） and grain yield were higher as compared with the control. However, mid and severe shading （S2 andS3, 67 and 35% of full sunshine, respectively） led to negative effects on these traits substantially. Moreover, superoxide dismutase （SOD）, peroxidase （POD） and cat- alase （CAT） activities in flag leaf were significantly greater under slight shading than those in other treatments, while the malondialdehyde （MDA） content was less than that under other treatments. In addition, the multiple-spike cultivar is more tolerant to shading than large-spike cultivar. In conclusion, slight shading after anthesis delayed leaf senescence, enhanced photosynthesis and grain filling, and thus resulted in higher grain yield.

关键词： winter wheat shading photosynthesis leaf senescence grain yield

DGR:dynamic gradient-based routing protocol for unbalanced and persistent data transmission in wireless sensor and actor networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第4期12卷 273-279页

作者： Yi GUO Zhe-zhuang xu cai-lian CHEN Xin-ping GUAN Department of Automation Shanghai diao Tong University Shanghai 200240 China

This paper is concerned with the routing protocol design for large-scale wireless sensor and actor networks (WSANs).The actor-sensor-actor communication (ASAC) strategy is first proposed to guarantee the reliability of persistent actor-actor *** keep network connectivity and prolong network lifetime,we propose a dynamic gradient-based routing protocol (DGR) to balance the energy consumption of the *** the different communication ranges of sensors and actors,the DGR protocol uses a data load expansion strategy to significantly prolong the network *** balance coefficient and the routing re-establishment threshold are also introduced to make the tradeoff between network lifetime and routing *** results show the effectiveness of the proposed DGR protocol for unbalanced and persistent data transmission.

关键词： Wireless sensor and actor networks Unbalanced and persistent data transmission Gradient-based routing