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THE KINETICS OF THE COMBINATION REACTION BETWEEN ENZYME AND SUBSTRATE

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Science in China,Ser.A 1976年第4期 505-528页

作者：周国城 Shanghai Institute of Biochemistry Academia Sinica

A stochastic analysis has been made for enzyme-substrate combination reaction systems, The relationship between diffusion-encounter and effective collision has been discussed. A new equation, derived for calculating the combination rates of multiple-active-site reaction systems, will serve to provide a theoretical basis for experimentally investigating the combination activation energies of liquid phase fast reaction systems. The calculated results show that the usual method employed to estimate the combination rates of multiple-active-site reaction systems is applicable only to the large activation energy concerned, but not to the small. In the latter ease, the coupling effect among active sites should not be *** this paper, the kinetic characteristics of liquid phase fast reaction systems involving conformational changes are further discussed. A new method of separation of kinetic constants has been suggested and the relationship between measuring signal and multi-barrier reactiou analyzed.

关键词： THE KINETICS OF THE COMBINATION REACTION BETWEEN ENZYME AND SUBSTRATE

Cellular responding kinetics based on a model of gene regulatory networks under radiotherapy

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Health 2010年第2期2卷 137-146页

作者： Jin-Peng Qi Yong-Sheng Ding Shi-Huang Shao Xian-Hui Zeng kuo-chen Chou 不详

Radiotherapy can cause DNA damage into cells, triggering the cell cycle arrest and cell apop-tosis through complicated interactions among vital genes and their signal pathways. In order to in-depth study the complicated cellular res- ponses under such a circumstance, a novel mo- del for P53 stress response networks is pro- posed. It can be successfully used to simulate the dynamic processes of DNA damage trans-ferring, ATM and ARF activation, regulations of P53-MDM2 feedback loop, as well as the toxins degradation. Particularly, it has become feasible to predict the outcomes of cellular response in fighting against genome stresses. Consequently, the new model has provided a reasonable framework for analyzing the complicated regu-lations of P53 stress response networks, as well as investigating the mechanisms of the cellular self-defense under radiotherapy.

关键词： P53 MDM2 DNA Damage IR Oscillations Radiotherapy

Steps to the clinic with ELF EMF

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Natural Science 2009年第3期1卷 157-165页

作者： Ash Madkan Martin Blank Edward Elson kuo-chen Chou Matthew S. Geddis Reba Goodman 不详

There have been many models to identify and analyze low-frequency motions in protein and DNA molecules. It has been successfully used to simulate various low-frequency collective motions in protein and DNA molecules. Low- frequency motions in biomacromolecules origi- nate from two common and intrinsic character-istics;i.e., they contain 1) a series of weak bonds, such as hydrogen bonds, and 2) a sub-stantial mass distributed over the region of these weak bonds. Many biological functions and dynamic mechanisms, including coopera-tive effects have been reported. In this regard, some phenomenological theories were estab-lished. However, differences in experimental outcomes are expected since many factors could influence the outcome of experiments in EMF research. Any effect of EMF has to depend on the energy absorbed by a biological organ-ism and on how the energy is delivered in space and time. Frequency, intensity, exposure dura-tion, and the number of exposure episodes can affect the response, and these factors can inter- act with each other to produce different effects. In addition, in order to understand the biologi- cal consequence of EMF exposure, one must know whether the effect is cumulative, whether compensatory responses result, and when ho-meostasis will break down. Such findings will have great potential for use in translation medi-cine at the clinical level without being invasive.

关键词： Electromagnetic Fields Hsp70 Interaction Mechanisms Low-Frequency Collective Motion

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悬浮月尘的遮挡模型

北京航空航天大学学报 2014年第5期40卷 624-628页

作者：陈阔李娜冯华君徐之海浙江大学现代光学仪器国家重点实验室杭州310027

探月活动中,月表的尘埃会对太阳翼等光电器件的工作效率造成严重影响.基于附着月尘的遮挡模型,从立体空间的角度分析了悬浮月尘对工作器件的遮挡,提出了悬浮月尘的单粒度遮挡模型,利用月尘的平均粒度可计算在指定立体空间内,定量月尘造... 详细信息

探月活动中,月表的尘埃会对太阳翼等光电器件的工作效率造成严重影响.基于附着月尘的遮挡模型,从立体空间的角度分析了悬浮月尘对工作器件的遮挡,提出了悬浮月尘的单粒度遮挡模型,利用月尘的平均粒度可计算在指定立体空间内,定量月尘造成的遮挡量;引入月尘的粒度分布函数,提出了悬浮月尘的多粒度遮挡模型,能够计算已知粒度分布函数的月尘在指定立体空间内造成的遮挡量;通过设计悬浮月尘遮挡的仿真实验,分别利用3种不同粒度大小的月尘进行实验,实验数据与悬浮月尘的单粒度、多粒度遮挡模型的理论计算值都较好吻合,实验结果证实了悬浮月尘遮挡模型的正确性与可靠性.

关键词：月尘悬浮遮挡粒度分布光电器件

Preparation and Properties of Alumina Heat Insulation Materials with High Purity

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China's Refractories 2015年第4期24卷 18-22页

作者： WANG Gang YUAN Bo WU Haibo DONG Binbin HAN Jianshen chen kuo LI Hongxia State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Research Co.Ltd. State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of Sciences

With the wide using of transparent alumina ceramics and synthetic sapphire, the demand of the furnace for them is promoted steadily, and the furnace lining materials are upgrading. Having low thermal conductivity and the same composition with transparent alumina ceramics and sapphire, porous alumina ceramics with. high purity are expected to lower the high energy consumption without contamination, in this paper, porous alumina ceramics with porosity of 75.3% -81.9% and impurity less than 0. 1% were prepared by a foaming method combined with gelcasting, using high purity alumina powders as raw materials. By changing the amount of foaming agent and the solid content, the microstructure and properties of porous ceramics were tailored. The compressive strength of the porous ceramics ranged .front （ 22.4 ±2.5） MPa to （48. 1± 3. 1 ） MPa, the thermal conductivity of porous ceramics at 1 000℃ ranged between 0. 41 -0. 65 W · （ m · K）^-1.

关键词： foaming high purity alumina porous ceramics microstructure thermal conductivity

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长江口平面盐度锋对径流量变化的响应特征

同济大学学报（自然科学版） 2022年第10期50卷 1458-1470页

作者：匡翠萍陈括武云龙王洁同济大学土木工程学院上海200092

基于1950年―2018年大通站月均径流量数据,应用MIKE21软件建立长江口平面二维水动力及盐度输运模型,探究三峡工程建成后径流量变化对长江口4支平面盐度锋位置与强度的影响。结果表明:在长江口口门处,全年平均盐度整体增加,南槽处增加最... 详细信息

基于1950年―2018年大通站月均径流量数据,应用MIKE21软件建立长江口平面二维水动力及盐度输运模型,探究三峡工程建成后径流量变化对长江口4支平面盐度锋位置与强度的影响。结果表明:在长江口口门处,全年平均盐度整体增加,南槽处增加最明显;除北港外,各支盐度锋都具有双锋面结构;锋面位置与径流量成线性关系,第一锋面位置变化较第二锋面明显;各锋面强度与径流量成二次函数关系,二次项系数在第一锋面处为正,第二锋面处为负。

关键词：长江口径流量盐度锋数值模拟

长江口深水航道及横沙东滩促淤圈围对滞流点的影响

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同济大学学报（自然科学版） 2017年第11期45卷 1621-1628页

作者：匡翠萍董智超陈括刘旭同济大学土木工程学院上海200092

滞流点位置的变化对河口拦门沙的形成和泥沙淤积具有极大的影响.基于MIKE3软件建立长江口水动力和盐度输运三维数学模型,采用实测资料对模型的潮位、流速、流向和盐度进行验证.运用验证好的数学模型模拟和分析长江口深水航道工程及横沙... 详细信息

滞流点位置的变化对河口拦门沙的形成和泥沙淤积具有极大的影响.基于MIKE3软件建立长江口水动力和盐度输运三维数学模型,采用实测资料对模型的潮位、流速、流向和盐度进行验证.运用验证好的数学模型模拟和分析长江口深水航道工程及横沙东滩促淤圈围工程对河口滞流点位置的影响,结果表明,(1)应用改进的近底层平均单宽通量计算公式确定滞流点的位置,验证结果良好,可以用该公式确定滞流点的位置;(2)深水航道工程的建设增大了水深和涨落潮流速,各汊道内落潮流量的增加明显高于涨潮流量的增加,且滞流点均向下游移动;(3)横沙东滩促淤圈围工程建成后,北港滞流点向下游移动约5km,北槽和南槽的滞流点则向上游移动约1km.

关键词：长江口深水航道横沙东滩促淤圈围滞流点数学模型

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大功率CO_2激光器输出窗口热性能分析

红外与激光工程 2017年第2期46卷 116-121页

作者：张阔陈飞李若斓杨贵龙中国科学院长春光学精密机械与物理研究所光电对抗技术创新研究室吉林长春130033 激光与物质相互作用国家重点实验室吉林长春130033 内蒙古化工职业学院机电系内蒙古呼和浩特010070

为了研究大功率CO_2激光发射过程中输出窗口吸收激光能量产生热性能变化的问题,建立了输出窗口传热学和结构力学耦合非稳态模型,通过对模型进行有限元分析得到表征输出窗口变化的温度、热变形和热应力等参数分布。首先,针对大功率CO_2... 详细信息

为了研究大功率CO_2激光发射过程中输出窗口吸收激光能量产生热性能变化的问题,建立了输出窗口传热学和结构力学耦合非稳态模型,通过对模型进行有限元分析得到表征输出窗口变化的温度、热变形和热应力等参数分布。首先,针对大功率CO_2激光特点,讨论了输出窗口材料Ga As和Zn Se的物理特性。然后,基于10 k W级大功率CO_2激光器光学谐振腔结构和输出窗口材料物理特性,建立了输出窗口传热学和结构力学的有限元模型。最后,利用COMSOL软件对该模型进行求解,得到以Ga As和Zn Se为材料的输出窗口的温度、热变形和热应力等参数分布,并对比分析不同窗口材料对参数的影响。研究表明:在10 k W级激光作用下,Zn Se窗口温升小于Ga As窗口;两种输出窗口产生μm量级热变形;由于Ga As材料的热导率高,Ga As窗口的热变形和热应力分布更为均匀。

关键词：大功率CO2激光输出窗口温度热变形热应力

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亚像素精度的行星中心定位算法

光学精密工程 2013年第7期21卷 1881-1890页

作者：陈阔冯华君徐之海李奇陈跃庭浙江大学现代光学仪器国家重点实验室浙江杭州310027

为实现深空探测中对行星目标的光学自主导航,提出了亚像素精度的行星中心定位方法。首先,建立了导航相机和目标行星的坐标变换关系,结合光学成像理论分析了行星成像的边缘特性;提出使用行星图像有且仅有的一段半圆形边缘,通过圆拟合法... 详细信息

为实现深空探测中对行星目标的光学自主导航,提出了亚像素精度的行星中心定位方法。首先,建立了导航相机和目标行星的坐标变换关系,结合光学成像理论分析了行星成像的边缘特性;提出使用行星图像有且仅有的一段半圆形边缘,通过圆拟合法实现行星的中心定位。然后,根据行星图像的边缘分布特征,改进了Canny算法以快速提取行星的真实边缘,并利用最大距离法提取半圆形边缘。最后,分析了传统高斯函数亚像素边缘检测算法的理论依据,基于成像理论提出了改进型高斯函数亚像素边缘检测算法,并通过圆拟合求得行星的亚像素中心。仿真和月亮实拍实验显示,改进型定位算法的精度达到了0.02和0.68pixel,比传统插值算法约高0.03和0.21pixel,在可靠性、定位精度、抗噪声等方面均满足深空探测的需要。

关键词：深空探测行星中心边缘检测亚像素圆拟合