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Nucleation and Growth Processes During Molecular-Beam Epitaxy of Ternary Compounds

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Chinese Physics Letters 1996年第11期13卷 855-858页

作者： MAO Hui-bing Department of Materials Science Fudan UniversityShanghai 200433

In this letter the effect of the different migration rates of two kinds of cations on the nucleation and growth processes during molecular-beam epitaxy of ternary systems was studied in detail by Monte Carlo *** AlGaAs ternary system,in which the migration rate of cation Ga is larger than that of Al,there are three types of nucleation:Ga-Ga,Al-Ga and Al-Al,which show different characteristics in the growth processes.

关键词： ternary simulation Ternary

顶空固相微萃取/气相色谱法快速萃取-解吸土壤中7种芳香族化合物

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分析测试学报 2025年第1期44卷 172-179页

作者：李丙阳王钊陈佳邱洪灯新疆师范大学化学化工学院新疆乌鲁木齐830000 中国科学院兰州化学物理研究所甘肃省天然药物重点实验室甘肃兰州730000

利用氧化石墨烯功能化修饰固相微萃取(GO@SPME)针,结合气相色谱(GC)-氢火焰离子化检测器(FID)建立了检测土壤中7种挥发性芳香烃及其衍生物(包括甲苯、氯苯、乙苯、对二甲苯、邻二甲苯、硝基苯和萘)的快速萃取和解吸策略。考察了萃取液... 详细信息

利用氧化石墨烯功能化修饰固相微萃取(GO@SPME)针,结合气相色谱(GC)-氢火焰离子化检测器(FID)建立了检测土壤中7种挥发性芳香烃及其衍生物(包括甲苯、氯苯、乙苯、对二甲苯、邻二甲苯、硝基苯和萘)的快速萃取和解吸策略。考察了萃取液体积、搅拌速率、萃取温度、加盐量、解吸温度、萃取时间和解吸时间对目标物萃取效果的影响,确定在土壤样品中加入内标物质(氘代甲苯),经甲醇提取,顶空固相微萃取快速富集,再结合GC-FID进行检测,基质匹配内标法定量分析。在优化的实验条件下,该方法在15 s内可实现对目标物的快速萃取与解吸(萃取时间12 s,解吸时间3 s)。土壤样品中7种挥发性芳香烃及其衍生物的线性关系良好,相关系数(r^(2))均不小于0.9989,方法检出限(LOD,S/N=3)为1.71~11.60μg/g,定量下限(LOQ,S/N=10)为5.70~38.67μg/g;在3个不同加标水平(60、120、180μg/g)下的平均回收率为87.3%~109%,相对标准偏差(RSD)不大于12%。该方法前处理简单快速,成本较低,数据稳定可靠,适用于土壤样品中芳香族类化合物的快速检测。

关键词：芳香烃及其衍生物氧化石墨烯顶空固相微萃取气相色谱法快速萃取-解吸策略土壤

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深挖路基边坡静态爆破布孔参数研究

价值工程 2025年第1期44卷 78-81页

作者：陈丙锋中国铁建港航局集团有限公司珠海519070

为了提高深挖路基边坡静态爆破效率,基于LS-DYNA数值模拟软件,对深挖路基边坡进行静态爆破数值模拟,从孔间距、临空面距离、孔深、倾角等方面分析布孔参数对静态爆破裂纹扩展的影响;以模拟结果为参考,进行现场静态劈裂施工,获得了良好... 详细信息

为了提高深挖路基边坡静态爆破效率,基于LS-DYNA数值模拟软件,对深挖路基边坡进行静态爆破数值模拟,从孔间距、临空面距离、孔深、倾角等方面分析布孔参数对静态爆破裂纹扩展的影响;以模拟结果为参考,进行现场静态劈裂施工,获得了良好的破岩效果。结果表明:随孔间距、临空面距离的减小,岩石裂纹发育更加充分,且临空面距离对裂纹扩展影响相较于孔间距对裂纹扩展的影响更为明显;随着孔深的增加,静态爆破对岩石的致裂效果减弱;钻孔倾角对边坡致裂、损伤影响较小;边坡裂隙对静态爆破两孔连线裂纹扩展起导向作用;此类模拟方法与现场施工吻合度很高,具有较广泛的适用性和经济性,为静态爆破现场工程提供了良好的科学指导。

关键词：公路路基 LS-DYNA 数值计算现场施工边坡

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Zrs5.8Al19.4（CO1-xCux）24.8 （x = 0-0.8 at.%） bulk metallic glasses for surgical devices applications

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Journal of Iron and Steel Research International 2018年第6期25卷 644-649页

作者： Kai-ming Han Jian-bing Qiang Ying-min Wang1 bing-bing Zhao Peter Haussler Key Laboratory of Materials Modification by Laser Ion andElectron Beams (Ministry of Education) Dalian Universityof Technology Dalian 116024 Liaoning China ArcX Coating Hub Asia Hoganais (China) Co. Ltd.Shanghai 201799 China Physics Institute Chemnitz University of Technology09107 Chemnitz Germany

Zr-Al-Co-Cu bulk metallic glasses （BMGs） are promising surgical materials. By using the electron concentration criterion for BMG composition design, a series of Zr55.8Al19.a（Co1-xCux）24.8 （x = 0-0.8 at.%） alloys were produced, of which BMG rod samples with different diameters were made by copper mold casting. Among these alloys, the Zr55.8A119.4Co17.36Cu7.44 BMG exhibited a centimeter-scale glass formation size （dmax = 12 mm）, an ultrahigh strength （δy = 2.04 GPa）, a large room-temperature plasticity （εp = 4.0%）, and a fracture toughness （KQ = 120 MPa m^l/2）, as well as good corrosion resistance in phosphate-buffered solution. The attAlnment of the combination of properties as large glass-forming ability with excellent mechanical and corrosion stability would suit the surgical devices applications.

关键词： Zr-Al-Co-Cu Bulk metallic glass Biomedical material Mechanical property

Independent component analysis to physical-layer network coding over wireless fading channels

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Journal of Systems Engineering and Electronics 2013年第2期24卷 196-203页

作者： bing Du Xiaoming Tao Department of Electronic Engineering Tsinghua University

A new combinational technology is proposed,which is feasible to apply physical-layer network coding（PNC） to wireless fading channels by employing the harmful interference *** key step of PNC is that sources broadcast signals simultaneously without orthogonal ***,the signals overlap in the free space at the *** the signals from different sources are mutual independent,rooted on this rational assumption,an enhanced joint diagonalization separation named altering row diagonalization（ARD） algorithm is exploited to separate these signals by maximizing the cost function measuring independence among *** ARD PNC（APNC） methodology provides an innovative way to implement signal-level network coding at the presence of interference and without any priori information about channels in fading *** conclusions,the proposed APNC performs well with higher bandwidth utility and lower error rate.

关键词： physical-layer network coding (PNC) independentcomponent analysis (ICA) joint diagonalization network coding cooperative communications.

Distillability of Sudden Death in Qutrit-Qutrit Systems under Global Mixed Noise

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Chinese Physics Letters 2019年第5期36卷 17-21页

作者： bing-bing Chai Jin-Liang Guo College of Physics and Materials Science Tianjin Normal UniversityTianjin 300387

Considering the influences of collective dephasing, multilocal qutrit-flip, local qutrit-flip, and the combination of global mixed noise, we study the dynamics of entanglement and the phenomenon of distillability of sudden death (DSD) in a qutrit-qutrit system under various decoherent noises. It is shown that the system always undergoes DSD when it interacts with multilocal and local qutrit-flip noise, and the time-determined bound entangled state is more dependent on different noises. Comparing with the cases of global mixed and collective dephasing noise,we conclude that the qutrit-flip noise is responsible for the DSD.

关键词： Distillability of Sudden Death in Qutrit-Qutrit Systems under Global Mixed Noise

Temporal and spatial chaos in the Kerr-AdS black hole in an extended phase space

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Chinese Physics C 2021年第5期45卷 202-211页

作者： bing Tang Department of Physics Jishou UniversityJishou 416000China

Based on the Melnikov method,we investigate chaotic behaviors in the extended thermodynamic phase space for a slowly rotating Kerr-AdS black hole under temporal and spatial *** results show that the temporal perturbation coming from a thermal quench of the spinodal region in the phase diagram may cause temporal chaos only when the perturbation amplitude is above a critical value,which involves the angular momentum *** the spatial perturbation,however,it is found that spatial chaos always occurs,independent of the perturbation amplitude.

关键词： Kerr-AdS black hole extended thermody namic phase space the Melnikov method thermal chaotic behavior

核桃分心木的体外消化特性及其对人体肠道菌群的影响

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核农学报 2025年第2期39卷 317-328页

作者：赵晓兰刘冰辛凤姣温博婷天津科技大学食品科学与工程学院天津300457 中国农业科学院农产品加工研究所北京100193 中国农业科学院农产品加工与营养健康研究院(沧州) 河北沧州061001

为阐明核桃分心木的体外消化特性及其对人体肠道菌群的影响,本研究以分心木为底物进行体外上消化道消化和体外结肠微生物发酵试验,对整个消化过程进行理化性质分析,通过微生物多样性分析研究体外发酵后分心木对人体肠道菌群多样性和组... 详细信息

为阐明核桃分心木的体外消化特性及其对人体肠道菌群的影响,本研究以分心木为底物进行体外上消化道消化和体外结肠微生物发酵试验,对整个消化过程进行理化性质分析,通过微生物多样性分析研究体外发酵后分心木对人体肠道菌群多样性和组成的影响,并通过代谢组学分析分心木对人体肠道菌群的影响及其在肠道中产生的代谢物。结果表明,肠道微生物发酵可以最大程度释放分心木中的多酚物质,显著提高其抗氧化能力,其中1,1-二苯基-2-三硝基苯肼(DPPH)自由基、2,2-联氮-二(3-乙基苯并噻唑-6-磺酸(ABTS)自由基清除能力以及亚铁还原抗氧化能力(FRAP)最高分别达22.95 mg·g^(-1)DW、3.88 mmol·g^(-1)DW和1.14 mmol·g^(-1)DW。经微生物发酵后,分心木的表面微观形态明显瓦解。16S rRNA微生物多样性分析发现,与空白对照组相比,试验组拟杆菌门、梭杆菌门和变形菌门的丰度增加;在属水平上,普雷沃氏菌属和梭杆菌属的相对丰度增加;而某些促炎细菌(如多雷亚菌属、另枝菌属、科利德克士菌属和嗜胆菌属)的生长繁殖受到显著抑制。非靶向代谢组学分析发现,共有1338种差异代谢物富集在269个京都基因与基因组百科全书(KEGG)通路中。其中,阿魏酸、伞形花序酮、表儿茶素、绿原酸、脱落酸、芥子酚醛和东莨菪碱等代谢物基因表达明显上调,这些代谢物分别富集在苯丙烷类、类黄酮、植物次级代谢物和次级胆汁酸的生物合成通路中。本研究为提高核桃加工副产物的附加价值提供了理论基础。

关键词：分心木体外消化体外发酵肠道菌群代谢物

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Experimental Study of the Influence of Flow Passage Subtle Variation on Mixed-flow Pump Performance

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 615-621页

作者： bing Hao CAO Shuliang State Key Laboratory of Hydroscience and Engineering Tsinghua University

In the mixed-flow pump design, the shape of the flow passage can directly affect the flow capacity and the internal flow, thus influencing hydraulic performance, cavitation performance and operation stability of the mixed-flow pump. However, there is currently a lack of experimental research on the influence mechanism. Therefore, in order to analyze the effects of subtle variations of the flow passage on the mixed-flow pump performance, the frustum cone surface of the end part of inlet contraction flow passage of the mixed-flow pump is processed into a cylindrical surface and a test rig is built to carry out the hydraulic performance experiment. In this experiment, parameters, such as the head, the efficiency, and the shaft power, are measured, and the pressure fluctuation and the noise signal are also collected. The research results suggest that after processing the inlet flow passage, the head of the mixed-flow pump significantly goes down; the best efficiency of the mixed-flow pump drops by approximately 1.5%, the efficiency decreases more significantly under the large flow rate; the shaft power slightly increases under the large flow rate, slightly decreases under the small flow rate. In addition, the pressure fluctuation amplitudes on both the impeller inlet and the diffuser outlet increase significantly with more drastic pressure fluctuations and significantly lower stability of the internal flow of the mixed-flow pump. At the same time, the noise dramatically increases. Overall speaking, the subtle variation of the inlet flow passage leads to a significant change of the mixed-flow pump performance, thus suggesting a special attention to the optimization of flow passage. This paper investigates the influence of the flow passage variation on the mixed-flow pump performance by experiment, which will benefit the optimal design of the flow passage of the mixed-flow pump.

关键词： mixed-flow pumps flow passage hydraulic performance pressure fluctuation model test