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Numerical Simulation of Dynamic Interaction Between Ice and Wide Vertical Structure Based on Peridynamics

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Computer Modeling in Engineering & Sciences 2019年第11期121卷 501-522页

作者： bin jia Lei Ju Qing Wang College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China

In the ice-covered oceanic region,the collision between sea ice and offshore structures will occur,causing the crushing failure of ice and the vibration of *** vibration can result in fatigue damage of structure and even endanger the crews’*** is no doubt that this ice-structure interaction has been noted with great interest by the academic community for a long time and numerous studies have been done through theoretical analysis,experimental statistics and numerical *** this paper,the bond-based Peridynamics method is applied to simulate the interaction between sea ice and wide vertical structures,where sea ice is modeled as elastic-plastic material,with a certain yield condition and failure *** equation of single-degree-of-freedom is considered to investigate the vibration features of the structure during the interaction *** damage of ice,ice forces and vibration responses of structure in the duration are obtained through numerical simulation.A parametric investigation is undertaken to identify the key parameters,such as ice thickness,the diameter of structure and relative velocity that trigger the ice crushing,ice forces and vibration responses of the *** indicate that all three parameters have a positive correlation with the overall level of ice force and vibration ***,a velocity coefficient is proposed to predict the vibration displacement based on its relation with ice speed.

关键词： Ice Peridynamics vertical structure interaction

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生物质碳气凝胶的研究现状及发展趋势

现代化工 2024年第1期44卷 59-62,67页

作者：张佳彬高丹丹张展硕黑龙江省木材科学研究所黑龙江哈尔滨150081 东北林业大学材料科学与工程学院黑龙江哈尔滨150040

生物质碳气凝胶具有高孔隙率､大比表面积､突出的机械性能和非凡的导电性等优点,是全球绿色发展背景下的研究热点。对生物质碳气凝胶的发展历程､原料种类､制备过程､应用领域及未来发展前景等方面进行了综述。

关键词：生物基碳气凝胶气凝胶

Spurious symmetry-broken phase in a bidirectional two-lane ASEP with narrow entrances

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Chinese Physics B 2017年第2期26卷 93-98页

作者： Bo Tian Rui jiang Mao-bin Hu bin jia School of Engineering Science University of Science and Technology of China Hefei 230026 China School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China

As one of the paradigmatic models of non-equilibrium systems, the asymmetric simple exclusion process（ASEP） has been widely used to study many physical, chemical, and biological systems. The ASEP shows a range of nontrivial macroscopic phenomena, among which, the spontaneous symmetry breaking has gained a great deal of attention. Nevertheless,as a basic problem, it has been controversial whether there exist one or two symmetry-broken phases in the ASEP. Based on the mean field analysis and current minimization principle, this paper demonstrates that one of the broken-symmetry phases does not exist in a bidirectional two-lane ASEP with narrow entrances. Moreover, an exponential decay feature is observed,which has been used to predict the phase boundary in the thermodynamic limit. Our findings might be generalized to other ASEP models and thus deepen the understanding of the spontaneous symmetry breaking in non-equilibrium systems.

关键词： Spontaneous symmetry breaking mean field analysis ASEP

Mobile CRISPR-Cas9 based anti-phage system in E. coli

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Frontiers of Chemical Science and Engineering 2022年第8期16卷 1281-1289页

作者： Zhou Cao Yuxin Ma bin jia Ying-Jin Yuan Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Escherichia coli is one of the most important microbial cell factories,but infection by bacteriophages in the environment may have a huge impact on its application in industrial ***,we developed a mobile CRISPR-Cas9 based anti-phage system for bacteriophages defense in *** conjugative plasmids pGM1(phosphoglucomutase 1)and pGM2 carrying one and two guide RNAs,respectively,were designed to defend against a filamentous *** results showed that the pGM1 and pGM2 could decrease the phage infection rate to 1.6%and 0.2%respectively in infected *** preventing phage infection in ***,the pGM2 decreased the phage infection rate to 0.1%,while pGM1 failed to block phage *** verification revealed that point mutations in protospacer or protospacer adjacent motif sequences of the phage genome caused loss of the defense *** results support the potential application of MCBAS in *** cell factories to defend against phage infections.

关键词： phage infections anti-phage CRISPR-Cas9,conjugative transfer synthetic biology

Effect of heat treatment on mechanical properties of thixoformed 7A09 aluminum alloy

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Transactions of Nonferrous Metals Society of China 2009年第S02期19卷 337-342页

作者： WANG Wei-wei jia bin-bin LUO Shou-jing School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The effects of solution-ageing treatment on the mechanical properties of semi-solid metal(SSM)products were studied by the method of orthogonal *** microstructure and tensile properties at different treatment conditions were *** results show that the effects of solution-ageing treatment were obviously influenced by the original microstructure of the SSM billet. Higher temperature is favorable for the sufficient solution of alloy elements,but the grains will grow up when treated at a higher temperature or soaked for a longer *** is a contradiction between the maximum tensile strength and elongation percentage. Under the condition of solution treatment at 475℃for 12 h and at 133℃for 20-22 h ageing,better properties including about 540 MPa of tensile strength and more than 6.3%of elongation can be obtained in *** surplus phases not melted in the substrate and the solution precipitated supersaturated elements are the main factors influencing the properties of the alloys.

关键词： 7A09 aluminum alloy heat treatment mechanical property semi-solid metal(SSM)

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唐钢新区3号高炉两段式炉身生产操作浅析

炼铁 2024年第1期43卷 21-24,29页

作者：贾彬高冰单庆林苑洪滨李振铠河钢集团唐钢公司技术中心河北唐山063000

唐钢新区3号高炉针对高球比炉料结构及冶炼特点,炉型设计采用两段式炉身结构,上段炉身角为79.56°,下段炉身角为82.58°。两段式炉身结构具有能适应高球比冶治炼、有利于发展边沿气流、削弱上部调剂效果、降低上部压差等冶炼特点。3号... 详细信息

唐钢新区3号高炉针对高球比炉料结构及冶炼特点,炉型设计采用两段式炉身结构,上段炉身角为79.56°,下段炉身角为82.58°。两段式炉身结构具有能适应高球比冶治炼、有利于发展边沿气流、削弱上部调剂效果、降低上部压差等冶炼特点。3号高炉现阶段入炉球团矿比例在40%左右,生产实践表明:炉型采用两段式炉身结构,能有效缓解高球比冶炼时,因球团矿还原膨胀导致的透气性差的问题;但是对大矿批冶炼不利,应选择合适的布料矩阵,随着入炉球团矿比例的提升,需加强对煤气流的控制,尤其是边沿气流的控制。

关键词：高炉两段式炉身高球比矿批煤气流

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粒度对熔剂性球团冶金性能及矿相结构的影响

烧结球团 2024年第2期49卷 59-64页

作者：李振铠高冰贾彬刘慧芬董齐李欢唐山钢铁集团有限责任公司河北唐山063000

为提高熔剂性球团质量,解析不同粒度条件下球团性能的变化规律,本文以唐钢新区带式焙烧机球团生产线为研究对象,通过投笼造球试验和冶金性能检测等方式,分别对8.0~10.0、10.0~12.5、12.5~16.0、16.0~20.0 mm 4种粒度条件下球团冶金性能... 详细信息

为提高熔剂性球团质量,解析不同粒度条件下球团性能的变化规律,本文以唐钢新区带式焙烧机球团生产线为研究对象,通过投笼造球试验和冶金性能检测等方式,分别对8.0~10.0、10.0~12.5、12.5~16.0、16.0~20.0 mm 4种粒度条件下球团冶金性能和矿相结构进行研究。结果表明:随着熔剂性球团粒度的逐渐提高,球团抗压强度从1767 N/P提高至3606 N/P,1 h还原度从78.5%降低至47.8%,还原膨胀指数略有降低,整体维持在12%以下,低温还原粉化指数(>6.3 mm)从87.8%降低至66.5%,低温还原粉化指数(>3.15 mm)从95%降低至87.2%,低温还原粉化指数(<0.5 mm)变化幅度较小,约为4%;随着熔剂性球团粒度的逐渐提高,气孔率降低,从38.93%降低为31.4%,液相率略有降低,固相比例显著提高,从41.05%提高至58.41%,致密度提高但液相率降低可能使得原本存在的链接状态失去效果,侧面减弱了熔剂性球团的低温还原粉化性能。因此,在熔剂性球团生产过程中应控制合适的球团粒度,改善熔剂性球团性能和微观结构,以便有利于高炉提产顺行。

关键词：带式焙烧机熔剂性球团粒度冶金性能矿相结构

NaCl,NaCl:Al与NaCl:Ca热释光峰值温度偏移特性

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物理学报 2024年第13期73卷 309-316页

作者：杨俊赵修良陈瑞达侯佳斌侯玉苗贺三军周超刘丽艳南华大学核科学技术学院衡阳421001 南华大学先进核能技术设计与安全教育部重点实验室衡阳421001

为深入地了解纯NaCl本身及其Al和Ca掺杂变体的热释光峰值温度偏移特性,通过第一性原理计算与热释光实验的结合方法,探讨了掺杂如何影响晶体的电子结构,并进一步分析热释光峰值温度的偏移机制.计算结果显示掺杂Al后NaCl的带隙略有增加至5... 详细信息

为深入地了解纯NaCl本身及其Al和Ca掺杂变体的热释光峰值温度偏移特性,通过第一性原理计算与热释光实验的结合方法,探讨了掺杂如何影响晶体的电子结构,并进一步分析热释光峰值温度的偏移机制.计算结果显示掺杂Al后NaCl的带隙略有增加至5.20 eV,掺杂Ca则导致带隙显著减小至0 eV,这些掺杂不仅改变了带隙宽度,还引入了不同的缺陷形成能,这可能导致热释光峰值温度在较低温度出现,且会随实验条件的变化而偏移.通过热释光实验对理论预测结果进行了验证,结果显示在加热速率增加时,所有样品的热释光峰值温度均有所增加,且NaCl:Al的变化最为显著,从276 K增至340 K;而在1—25 mGy剂量范围内随着辐照剂量的增加,热释光峰值温度的增长变化较小,尤其是NaCl:Ca仅从195 K增至202 K.基于第一性原理的计算及热释光峰值温度偏移特性的实验研究对于不同掺杂材料的应用具有重要参考意义.

关键词：热释光特性 NaCl掺杂第一性原理电子结构

南秦岭旬北地区汞锑金成矿带新发现一处中型金矿(16.89 t)

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中国地质 2024年第3期51卷 1076-1077页

作者：杨本昭贾彬张振唐明锋孟五一郑鑫崔小齐陕西地矿第一地质队有限公司陕西安康725000 中国地质调查局西安矿产资源调查中心陕西西安710100

1研究目的(Objective)陕西省地矿第一地质队有限公司依托“陕西省旬阳公馆—青铜沟汞锑矿深部及外围汞锑金矿普查”项目在南秦岭旬北地区开展汞锑金矿普查工作,在公馆、青铜汞锑矿床之间新发现中型老君庙金矿床(图1a)。

关键词：南秦岭旬北地区金成矿带老君庙金矿床汞锑矿床锑金矿