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Calculation of Hugoniot properties for shocked nitromethane based on the improved Tsien's EOS

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Acta Mechanica Sinica 2010年第3期26卷 365-370页

作者： Bo zhao Ji-Ping cui Jing Fan Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of SciencesBeijing 100190 China

We have calculated the Hugoniot properties of shocked nitromethane based on the improved Tsien＇s equa- tion of state （EOS） that optimized by ＂exact＂ numerical molecular dynamic data at high temperatures and pressures. Comparison of the calculated results of the improved Tsien＇s EOS with the existed experimental data and the direct simu- lations show that the behavior of the improved Tsien＇s EOS is very good in many aspects. Because of its simple analytical form, the improved Tsien＇s EOS can be prospectively used to study the condensed explosive detonation coupling with chemical reaction.

关键词： Equation of state High pressures andtemperatures Shocked nitromethane Hugoniot properties

掺杂对TiC_(2)纳米片析氢反应的第一性原理研究

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原子与分子物理学报 2025年第3期42卷 29-34页

作者：孙楠楠赵翠莲潘美玲赵志超张宇河北水利电力学院基础部沧州061000 河北省数据中心相变热管理技术创新中心沧州061000

过渡金属二碳族化物单层作为一种廉价而丰富的材料,在制氢催化剂方面的应用越来越受到人们的关注.在这项工作中,基于第一性原理计算研究了掺杂二碳化钛单层的析氢还原.我们发现掺杂元素和浓度对单分子膜的催化能力有强烈的影响.结果表明... 详细信息

过渡金属二碳族化物单层作为一种廉价而丰富的材料,在制氢催化剂方面的应用越来越受到人们的关注.在这项工作中,基于第一性原理计算研究了掺杂二碳化钛单层的析氢还原.我们发现掺杂元素和浓度对单分子膜的催化能力有强烈的影响.结果表明,在高氢覆盖率内,O和V掺杂能有效的降低氢吸附的吉布斯自由能.低密度掺杂可以提高催化能力.我们进一步研究表明,由于V原子在二碳化钛(TiC_(2))单层中具有最低的负形成能,因此比其他过渡金属原子更容易取代Ti原子.期望掺钒TiC_(2)单分子膜能以更高的效率应用于水电解.

关键词：密度泛函理论 TiC_(2)单层片覆盖率掺杂

维普期刊数据库博看期刊

Supercritical fluid extraction and gas chromatography analysis of arsenic species from solid matrices

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Chinese Chemical Letters 2016年第2期27卷 241-246页

作者： Zhi-Feng Wang zhao-Jie cui School of Environmental Science and Engineering Shandong University

A method in combination with derivatization-supercritical fluid extraction（SFE） and gas chromatography（GC） for the speciation and quantitative determination of dimethylarsinate（DMA）, monomethylarsonate（MMA） and inorganic arsenic in solid matrices was investigated. Thioglycolic acid methyl ester（TGM） and thioglycolic acid ethyl ester（TGE） were evaluated as derivatization reagents. The effects of pressure, temperature, flow rate of supercritical CO_2, extraction time, modifier and microemulsion on the efficiency of extraction were systematically investigated. The procedure was applied to the analysis of real soil and sediment samples. Results showed that TGE was more effective for arsenic speciation as a derivatization reagent. Modifying supercritical CO_2 with methanol can greatly improve the extraction efficiency. Further, the addition of microemulsion containing surfactant Triton X-100 can further enhance recoveries of arsenic species. The optimum extraction conditions were 100 ℃, 30 MPa, 10 min static and 25 min dynamic extraction with 5%（v/v） methanol, and surfactant modified supercritical CO_2. Detection limits in solid matrices were 0.15, 0.3 and 1.2 mg/kg for DMA, MMA and inorganic arsenic,respectively. The method was validated by the recovery data. The resulting method was fast, easy to perform and selective in the extraction and detection of various arsenic species in solid matrices.

关键词： Supercritical fluid extraction Arsenic species analysis Thioglycolic acid methyl ester(TGM) Thioglycolic acid ethyl ester(TGE) Derivatization Gas chromatography

Enhanced Crystallization Kinetics of PLLA by Ethoxycarbonyl Ionic Liquid Modified Graphene

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Chinese Journal of Polymer Science 2019年第3期37卷 243-252页

作者： Pei Xu zhao-Pei cui Gang Ruan Yun-Sheng Ding Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering and Anhui Key Laboratory of Advanced Functional Materials and Devices Hefei University of Technology

To investigate the performance of graphene(Gra) modified with ethoxycarbonyl ionic liquid(IL), chain mobility and crystallization kinetics of poly(L-lactic acid)(PLLA), a series of PLLA nanocomposites have been prepared using solution-cast *** can improve the dispersion of Gra in PLLA matrix and the samples containing IL have higher growth rate of PLLA spherulite than neat PLLA does. PLLA/IL/Gra and PLLA/2 Gra exhibit the same relaxation strength and time of αN relaxation that corresponds to the longest normal mode motion at 110-140 °C. PLLA/IL/Gra shows a faster crystallization rate than PLLA/2 Gra does, which might be attributed to the Gra-imidazolium cation interaction in IL modified Gra, the significant dispersion effect of IL at Gra surface, and the increase of nuclei density of PLLA/IL/Gra.

关键词： Ionic liquid Graphene PLLA Crystallization Dielectric behavior

WAPN:a distributed wormhole attack detection approach for wireless sensor networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 279-289页

作者： Fan-rui KONG Chun-wen LI Qing-qing DING Guang-zhao cui Bing-yi cui Department of Automation. Tsinghua University Beijing 100084. China State Key Lab of Power Systems Departmet of Electrical Engineering Tsinghua University Beijing 100084 China State Key Lab of Informational Electric Apparatus in Henan Zhengzhou 450002 China Department of Phvsics Nanjing University Nanjing 210093 China

As the applications of wireless sensor networks(WSNs) diversify,providing secure communication is emerging as a critical requirement. In this paper,we investigate the detection of wormhole attack,a serious security issue for WSNs. Wormhole attack is difficult to detect and prevent,as it can work without compromising sensor nodes or breaching the encryption key. We present a wormhole attack detection approach based on the probability distribution of the neighboring-node-number,WAPN,which helps the sensor nodes to judge distributively whether a wormhole attack is taking place and whether they are in the in-fluencing area of the attack. WAPN can be easily implemented in resource-constrained WSNs without any additional requirements,such as node localization,tight synchronization,or directional antennas. WAPN uses the neighboring-node-number as the judging criterion,since a wormhole usually results in a significant increase of the neighboring-node-number due to the extra attacking link. Firstly,we model the distribution of the neighboring-node-number in the form of a Bernoulli distribution. Then the model is simplified to meet the sensor nodes' constraints in computing and memory capacity. Finally,we propose a simple method to obtain the threshold number,which is used to detect the existence of a wormhole. Simulation results show that WAPN is effective under the conditions of different network topologies and wormhole parameters.

关键词： Wireless sensor networks (WSNs) Security Wormhole detection

Effect of casting speed on surface quality of horizontal direct chill casting 7075 aluminum alloy ingot

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Acta Metallurgica Sinica(English Letters) 2011年第5期24卷 399-404页

作者： Qingfeng ZHU Zhihao zhao Jianzhong cui Xiangjie WANG Ke QIN Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang 110819 China

7075 aluminum alloy ingot with the diameter izontal direct chill casting in different casting of 100 mm has been produced by horspeed. The effect of the casting speed on the ingot surface and subsurface layer was studied by surface observation and subsurface structure analysis. It was found that increasing the casting speed results in the adding of segregation knots in the ingot surface. The thickness of the dendrite microstrueture layer in the subsurface reduces with increasing the casting speed. And the elements of Zn, Cu and Mg enrich in the coarse dendrite microstructure layer of the ingot.

关键词： Horizontal direct chill casting Casting speed 7075 aluminumalloy Surface quality

Accumulation of Carbohydrate and Regulation of 14-3-3 Protein on Sucrose Phosphate Synthase(SPS) Activity in Two Tomato Species

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Journal of Integrative Agriculture 2014年第2期13卷 358-364页

作者： WANG Li cui Na zhao Xiao-cui FAN Hai-yan LI Tian-lai Biological Science and Technology College Shenyang Agricultural University Key Laboratory of Protected Horticulture Ministry of Education/College of HorticultureShenyang Agricultural University

To explore the differences of carbohydrate metabolism in two tomato species and discuss the possible regulation of 14-3-3 proteins on the sucrose phosphate synthase （SPS） activity, we determined the contents of soluble sugar and starch through high performance liquid chromatography （HPLC）. The activities of sugar-metabolizing enzymes were assayed in desalted extract, and the relative expression levels of related genes in sugar metabolism were determined though real-time RT-PCR. The results indicated that glucose and fructose were mainly accumulated during the maturation of the fruit because of the high acid invertase （AI） and neutral invertase （NI） in Micro-Tom （Solanum lycopersicum） fruit, while in Solanum chmielewskii fruit, SPS which went along with the change of sucrose content led to the rapid sucrose increase during the fruit ripening. TFT1 and TFT10, belonging to 14-3-3 protein in tomato, were likely to down-regulated SPS activity during young and intumescence period.

关键词： Micro-Tom Solanum chmielewskii carbohydrate accumulation 14-3-3 proteins fruit development

航空重力异常数据稳定高精度向下延拓方法研究

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地球与行星物理论评(中英文) 2025年第3期56卷 264-277页

作者：柯宝贵赵予菲徐凡凡赵翠李泰航中国测绘科学研究院北京100036 华中科技大学精密重力测量研究设施武汉430074 兰州交通大学测绘与地理信息学院兰州730070 北京联合大学应用科技学院北京102200

航空重力异常向下延拓的本质是求解第一类Fredholm方程,属于不适定性的问题.稳定高精度向下延拓方法一直以来都是该领域的研究热点.为抑制边缘效应和提升计算效率,分别对所用数据进行扩边和快速傅里叶变换处理.为增大向下延拓距离、提... 详细信息

航空重力异常向下延拓的本质是求解第一类Fredholm方程,属于不适定性的问题.稳定高精度向下延拓方法一直以来都是该领域的研究热点.为抑制边缘效应和提升计算效率,分别对所用数据进行扩边和快速傅里叶变换处理.为增大向下延拓距离、提高稳定性和延拓精度,利用模拟重力异常数据和实测航空重力数据对比分析了积分迭代法、Tikhonov正则化迭代法、Barzilai-Borwein法、迭代最小二乘法和半迭代方法、改进的共轭梯度法向残差法等六种向下延拓方法.结果表明:在数据没有噪声的理想情况下,Barzilai-Borwein法的收敛速度最快,且初始延拓均方误差值低,延拓精度高,优势明显.迭代最小二乘法不够稳定.Tikhonov正则化迭代方法在达到延拓稳定前,经历了误差增加的状态,且初始均方误差值较高,而其余的几种方法延拓效果类似较为一般.在模拟数据中添加噪声后,改进的共轭梯度法向残差法,对噪声的抑制效应最好.且该方法在实际数据向下延拓的过程中,能够实现稳定向下延拓,延拓精度优于其他五种延拓方法.

关键词：航空重力数据向下延拓频率域共轭梯度法向残差法积分迭代法

白细胞计数、C反应蛋白及降钙素原联合检测对儿童穿孔性阑尾炎的预测价值

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妇儿健康导刊 2025年第1期4卷 111-114,127页

作者：孙丽云许银洁崔钊长春中医药大学吉林长春130117 吉林省儿童医疗中心吉林长春130000

目的探讨白细胞计数(WBC)、C反应蛋白(CRP)及降钙素原(PCT)联合检测对儿童穿孔性阑尾炎的预测价值。方法回顾性分析2017年1月至2023年4月吉林省儿童医疗中心收治的427例阑尾炎患儿的临床资料,其中穿孔组113例,非穿孔组314例。采用单因... 详细信息

目的探讨白细胞计数(WBC)、C反应蛋白(CRP)及降钙素原(PCT)联合检测对儿童穿孔性阑尾炎的预测价值。方法回顾性分析2017年1月至2023年4月吉林省儿童医疗中心收治的427例阑尾炎患儿的临床资料,其中穿孔组113例,非穿孔组314例。采用单因素、多因素分析法分析穿孔性阑尾炎的危险因素,采用受试者工作特征曲线获取最佳截断值并评估各方法的预测效能。结果单因素分析显示,WBC、CRP、PCT可作为阑尾穿孔的影响因素(P1,P<0.05)。WBC、CRP、PCT三项联合预测效能优于两项及单独预测,灵敏度为0.894,特异度为0.764,阳性预测值为74.64%,阴性预测值为81.94%。WBC、CRP、PCT最佳截断值分别为17.42×10^(9)/L、34.09 mg/L、0.355μg/L。结论WBC、CRP、PCT联合检测可以准确地预测儿童穿孔性阑尾炎的发生,能够作为术前早期评估儿童阑尾炎严重程度的方法。

关键词：白细胞计数 C反应蛋白降钙素原儿童穿孔性阑尾炎