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pH响应型聚合物Eudragit L-100固定化阿魏酸酯酶产阿魏酸的研究

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食品与发酵工业 2023年第4期49卷 224-229页

作者：王凯鹏郑晶莹徐雪阳丁怡玲吕永梅刘金彬余晓红靳文斌盐城工学院海洋与生物工程学院江苏盐城224051

阿魏酸酯酶处理固体底物木质纤维素时,难以实现游离酶与产物或固体残留的完全分离,增加了生产成本。该实验以1-乙基-3-(3-二甲氨基丙基)碳二亚胺1-乙基-(3-二甲基氨基丙基)碳二亚胺盐酸盐[1-ethyl-3-(3-dimethylaminopropyl)carbodiimid... 详细信息

阿魏酸酯酶处理固体底物木质纤维素时,难以实现游离酶与产物或固体残留的完全分离,增加了生产成本。该实验以1-乙基-3-(3-二甲氨基丙基)碳二亚胺1-乙基-(3-二甲基氨基丙基)碳二亚胺盐酸盐[1-ethyl-3-(3-dimethylaminopropyl)carbodiimide,EDC]为交联剂,将阿魏酸酯酶共价固定在pH响应型聚合物Eudragit L-100上可以解决这样的问题。通过对交联剂浓度、pH、时间、温度等固定化酶条件的优化,确定了制备固定化酶的最佳条件。在最佳固定化条件(EDC 5 g/L、pH 6.0、固定化时间1 h、温度25℃)下,固定化酶表现出比游离酶更好的热稳定性,40℃反应1 h后,固定化酶和游离酶的残留活性分别约为50%和30%。此外,固定化酶的pH稳定性也显著提高。以脱淀粉麦麸为底物生产阿魏酸(ferulic acid,FA)时,5次反应后固定化酶残留活性仍保持在64%左右。该研究提出的采用pH响应型聚合物Eudragit L-100固定化酶对于不溶底物的酶法水解提供了一个非常简单有效的方法。

关键词：阿魏酸酯酶固定化阿魏酸热稳定性麦麸

The effect of crack tip environment on crack growth behaviour of a low alloy steel at cathodic potentials in artificial seawater

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Journal of Materials Science & Technology 2020年第19期54卷 119-131页

作者： Yong Li Zhiyong liu Endian Fan Zhongyu Cui jinbin Zhao Corrosion and Protection Center University of Science and Technology BeijingBeijing 100083China Shandong Key Laboratory of Corrosion Science Institute of OceanologyChinese Academy of SciencesQingdao 266071China School of Materials Science and Engineering Ocean University of Chin1Qingdao 266100China Jiangsu Key Laboratory for Premium Steel Material Nanjing Iron&Steel United Co.Ltd.Nanjing 210035China

The environment at crack tip and its effect on the crack growth behaviour of low alloy steel-E690 steel were studied at cathodic potentials in artificial *** results showed that the micro environment at crack tip and crack growth behaviour were related to the electrochemical reactions at crack tip,which were affected by the stress state and applied *** crack tip environment was acidified under cyclic loading,resulting from the crack tip anodic dissolution reaction and corresponding hydrolysis *** of the hydrogen evolution and the inhibited anodic dissolution inside the crack,the crack tip p H increases as the cathodic potential *** effect of cathodic potentials on the electrochemical reactions caused the variation of the hydrogen content,which influenced the crack growth rate because the crack growth behaviour was controlled by hydrogen embrittlement *** resulted in a fact that with the negative decrease of potential,the crack growth rate first decreased and then increased,with the minimum rate at-0.75 *** the crack growth path exhibited transgranular fracture.

关键词： Low alloy steel Stress state Cathodic potential Crack tip environment Crack growth behaviour

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刷式密封绕流阻力特性的数值研究

农业装备与车辆工程 2020年第11期58卷 1-5页

作者：张宝迪刘美红康宇驰刘晋宾宋晓磊昆明理工大学机电工程学院云南省昆明市650500

以叉排管束模型刷丝束的二维截面建立数值计算模型,采用计算流体力学分别在瞬态和稳态下对流场进行数值模拟。分析了刷式密封中压差、轴向排数以及管距对绕流阻力特性的影响。研究结果表明:当压差在0.1~0.5MPa变化,前14排刷丝阻力逐渐增... 详细信息

以叉排管束模型刷丝束的二维截面建立数值计算模型,采用计算流体力学分别在瞬态和稳态下对流场进行数值模拟。分析了刷式密封中压差、轴向排数以及管距对绕流阻力特性的影响。研究结果表明:当压差在0.1~0.5MPa变化,前14排刷丝阻力逐渐增大,最大值为12N,第15排刷丝增大至30N。在0.5MPa的压差情况下,其管距增大0.5mm,总阻力增大100N。随着轴向排数的增加,刷丝绕流阻力减小且减小幅度逐渐降低。瞬态下,前14排刷丝绕流阻力增长幅度在0~0.005之间,第15排刷丝跳变至0.025~0.07之间,这样容易对刷丝根部焊接处造成疲劳破坏。

关键词：刷式密封叉排管束数值模拟绕流阻力特性计算流体力学性能分析

Progress of Double Star Program

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空间科学学报 2006年第Z1期26卷 7-13页

作者： liu Zhenxing CAO jinbin Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China

The Double Star Programme (DSP) is the first joint space mission between China and ESA. The mission, which is made of two spacecraft, is designed to investigate the magnetospheric global processes and their response to the interplanetary disturbances in conjunction with the Cluster mission. The first spacecraft, TC-1 (Tan Ce means "Explorer"), was launched on 30 December 2003, and the second one, TC-2, on 25 July 2004 on board two Chinese Long March 2C. Due to the importance of and success of DSP, both CNSA and ESA approved the extension of DSP. This paper presents DSP mission and some important scientific results made based on the data of DSP.

关键词： Double Star Program, Magnetosphere

A Brief Introduction and Recent Progress of the Geospace Double Star Program

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空间科学学报 2004年第Z1期24卷 39-45页

作者： liu Zhenxing CAO jinbin Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 China

The Geospace Double Star Project (DSP) consists of two small satellites operating in the near-earth equatorial and polar regions, respectively. The goals of DSP are: (1) to provide high-resolution field, particle, and wave measurements in some important near-earth active regions which have not been covered by current ISTP missions, such as the near-earth plasma sheet and its boundary layer, the ring current, the radiation belts, the dayside magnetopause boundary layer, and the polar region; (2) to investigate the trigger mechanisms of magnetic storms, magnetospheric substorms, and magnetospheric particle events,as well as the responses of geospace storms to solar activities and interplanetary disturbances; (3) to set up the models describing the spatial and temporal variations of the near-earth space *** realize the above goals, the equatorial satellite TC-1 and the polar satellite TC-2 will accommodate, respectively, eight instruments on board. TC-1was launched successfully in December 2003 while the polar satellite (TC-2)will be launched in July 2004. The orbit of the equatorial satellite TC-1 consists of a perigee at 550 km, an apogee at 60 000 km, and an inclination of about 28.5; while the orbit of the polar satellite will have a perigee of 700 km, an apogee of 40 000 km, and an inclination of about 90. The two satellites will take coordinated measurements with Cluster Ⅱ and will first form a "six-point exploration" in *** operational status of TC-1 are introduced in this paper.

关键词： Solar-terrestrial space physics, Double star exploration project,International cooperation

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手术治疗老年急腹症患者110例分析

中国医药科学 2011年第17期1卷 84-85页

作者：刘娜柳金斌刘钢梁炜峰李鹏衡星韩晓锋宁小晶北京市隆福医院普通外科北京100010

目的探讨笔者所在医院手术治疗老年急腹症患者的临床资料,进一步提高老年急腹症患者手术疗效。方法选择2009年5月～2010年10月笔者所在医院手术治疗老年急腹症患者110例。其中男58例,女52例,年龄65～93岁,平均(74.0±5.5)岁,其中86例(78... 详细信息

目的探讨笔者所在医院手术治疗老年急腹症患者的临床资料,进一步提高老年急腹症患者手术疗效。方法选择2009年5月～2010年10月笔者所在医院手术治疗老年急腹症患者110例。其中男58例,女52例,年龄65～93岁,平均(74.0±5.5)岁,其中86例(78.2%)合并至少一种基础疾病。结果手术证实急性阑尾炎43例,占39.1%;机械性肠梗阻38例,占34.5%;空腔脏器穿孔16例,占14.5%;胆结石并急性胆囊或胆管炎11例,占10.0%;绞窄性疝2例,占1.8%。其中96例(87.3%)术后顺利康复无主要并发症;14例(12.7%)术后合并至少一种并发症(包括死亡),主要为心肺并发症13例、感染性休克1例。术后3例住院死亡,死亡原因分别为围术期心肌梗死2例、感染性休克1例。结论老年患者急腹症总体疗效满意,临床工作中应全面分析,及早诊断,积极审慎手术处理。

关键词：急腹症老年患者

Progress of Double Star Program 2006—2008

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空间科学学报 2008年第5期28卷 385-389页

作者： liu Zhenxing CAO jinbin State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190

This paper presents the status of two satellites of Double Star Program,and a part of scientific results based on the data of Double Star Program obtained during the period of *** scientific results in the magnetosphe... 详细信息

关键词：地球空间双星探测计划中国研究进展空间技术

Magnetospheric Physics in China:2008-2010

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空间科学学报 2010年第5期30卷 445-455页

作者： Cao jinbin liu Zhenxing Pu Zuyin School of Astronautics Beihang University Beijing 100191 State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences School of Earth and Space Sciences Peking University

In the past two years,most of the works on magnetospheric physics were made by using the data of Double Star Program and Cluster *** some works were still conducted by computer simulation or using the data from other space missions and ground geomagnetic *** paper briefly review these previous works based on papers selected from the 28 publications from April 2008 to April *** subjects covered various sub-branches of magnetospheric physics,including geomagnetic storm,magnetospheric substorm and etc.

关键词：磁层亚暴物理学 Cluster 中国计算机模拟双星计划观测数据飞行任务

Response of magnetic fields at geosynchronous orbit and on the ground to the sudden changes of IMF B_Z

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Science China(Technological Sciences) 2014年第2期57卷 360-367页

作者： DONG YiXuan CAO jinbin liu WenLong ZHANG Lei LI liuYuan Beijing Institute of Spacecraft Environment Engineering Space Science Institute School of Astronautics Beihang University Institute of Telecommunication Satellite China Academy of Space Technology

The rapid change in the Earth’s magnetosphere caused by solar wind disturbances has been an important part of the solar wind-magnetosphere *** most of the previous studies focused on the perturbation of the Earth’s magnetic field caused by solar wind dynamic pressure *** this paper,we studied the response of geosynchronous magnetic field and the magnetic field to the rapid southward turning of interplanetary magnetic field during the interval 1350 1420 UT on 7May *** this event,BZ component of the interplanetary magnetic field decreased from 15 nT to 10 nT within 3 min(1403 1406 UT).The geosynchronous magnetic field measured by three geosynchronous satellites(GOES 10 12)first increased and then *** variations of magnetic field strength in the morning sector(9 10 LT)were much larger than those in the dawn sector(5 LT).Meanwhile,the H components of geomagnetic field on the ground have similar response features but exhibit latitude and LT dependent *** with H components,the D components do not have regular *** the solar wind dynamical pressure encounters small variations,the magnetic field both in space and on the ground does not display similar ***,the increase of geomagnetic field in the dawn sector is caused by the southward turning of IMF(interplanetary magnetic field)*** results will help to better understand the coupling process of geomagnetic filed and interplanetary magnetic field.

关键词： interplanetary magnetic field (IMF) solar wind geosynchronous orbit geomagnetic field