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对旋光法测蔗糖转化反应速度常数的改进 被引量:1
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作者 王清华 《山西农业大学学报》 CAS 1997年第3期298-301,共4页
本文以lg(αt-αt+△t)对t作图,求蔗糖转化反应速度常数。并讨论计算结果与所取时间间隔△t大小的关系。
关键词 旋光度 速度方程式 蔗糖 转化反应
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气体渗碳动力学的研究 被引量:13
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作者 凌国平 马智勇 《金属热处理》 EI CAS CSCD 北大核心 2000年第2期36-39,共4页
研究了925℃时,在实际渗碳气氛中的渗碳速度。建立了以CO解离吸附与氧脱附为基础的气体渗碳动力学模型。试验结果表明,在给定的渗碳气氛中,表面存在一个临界氧覆盖率θ0,当表面的氧覆盖率θ0小于θ0时,控制渗碳速度的是CO的解离吸附,当... 研究了925℃时,在实际渗碳气氛中的渗碳速度。建立了以CO解离吸附与氧脱附为基础的气体渗碳动力学模型。试验结果表明,在给定的渗碳气氛中,表面存在一个临界氧覆盖率θ0,当表面的氧覆盖率θ0小于θ0时,控制渗碳速度的是CO的解离吸附,当表面的氧覆盖率θ0大于氧临界覆盖率θ0时,渗碳速度由氧的脱附所决定。 展开更多
关键词 气体渗碳 速度方程式 吸附 动力学 一氧化碳
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邻苯二甲酸二异丁酯的酯化合成 被引量:2
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作者 柯昌英 《化学世界》 CAS 1986年第10期440-442,共3页
邻苯二甲酸二异丁酯(DIBP)是一种鲜为人知的主增塑塑剂。近年来,由于邻苯二甲酸二辛酯、二丁酯等主增塑剂格价一涨再涨,致使价格低廉,且相对稳定的DIBP 销路日益见好。加之,DIBP 与聚氯乙烯树脂相溶性极好,开始广泛地用于民用聚氯乙烯... 邻苯二甲酸二异丁酯(DIBP)是一种鲜为人知的主增塑塑剂。近年来,由于邻苯二甲酸二辛酯、二丁酯等主增塑剂格价一涨再涨,致使价格低廉,且相对稳定的DIBP 销路日益见好。加之,DIBP 与聚氯乙烯树脂相溶性极好,开始广泛地用于民用聚氯乙烯制品中。随着生产DIBP 的厂家逐渐增多,为大规模生产设计提供基础数据,显得愈来愈重要。鉴于酯化合成DIBP 反应动力学的各参数目前尚无公开报道,本文为生产所急需,进行了实验探讨。 展开更多
关键词 动力学方程式 化学反应速度方程式 二级反应 反应系统 一级反应 醋化
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试议以全要素生产率作为我国宏观经济效益指标
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作者 支道隆 《国际经贸研究》 CSSCI 1998年第1期57-60,共4页
全要素生产率(Total Factor Productivity,简称T.F.P)是西方国家通用的宏观经济效率指标。TFP的基本算式是A=Q/K<sup>W1</sup> L<sup>W2</sup>,就是柯布——道格拉斯生产函数的表达方法。该式可以计算某一时... 全要素生产率(Total Factor Productivity,简称T.F.P)是西方国家通用的宏观经济效率指标。TFP的基本算式是A=Q/K<sup>W1</sup> L<sup>W2</sup>,就是柯布——道格拉斯生产函数的表达方法。该式可以计算某一时期的技术水平,并由此计算技术进步对新增产值的贡献,但不能直接算出技术进步对产值增长的贡献。美国经济学家索洛推导出增长速度方程式,借以揭示经济增长过程中技术进步所引起的作用:A’=Q’-K<sup>W1</sup>-L’<sup>W2</sup>。 展开更多
关键词 全要素生产率 技术进步 经济增长率 国内生产总值 固定资产投资 道格拉斯生产函数 增长幅度 速度方程式 投资效果系数 效益系数
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三氯甲烷光化反应动力学的初步研究
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作者 王惠兰 《江汉大学学报(社会科学版)》 1993年第6期77-80,88,共5页
三氯甲烷光化反应动力学未见报道,本文采用自制光化反应器,220v、3w黑光灯(λ≤380nm)光照射,在2gl^(-1)锐矿型二氧化钛的悬浮液中,用氯离子选择性电极测定三氯甲烷降解反应的机数、速度方程式、速度常数、量子效率等动力学参数。并初... 三氯甲烷光化反应动力学未见报道,本文采用自制光化反应器,220v、3w黑光灯(λ≤380nm)光照射,在2gl^(-1)锐矿型二氧化钛的悬浮液中,用氯离子选择性电极测定三氯甲烷降解反应的机数、速度方程式、速度常数、量子效率等动力学参数。并初步提出三氯甲烷光化吸附多相催化反应的机理对废水、土壤和地下水中含氯有毒农药和化学药品的消除,有着重大意义。 展开更多
关键词 反应的级数 速度方程式 速度常数 量子效率
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试述贡献率测算中应注意的几个问题 被引量:1
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作者 张良强 《福建江夏学院学报》 1997年第4期8-11,共4页
随着当代科学技术的迅猛发展,科学技术进步对经济增长的作用受到普遍的重视。科学地测定科技进步的在经济增长中的贡献份额,对认识科技进步的现状和水平,把握经济增长方式的状况,进行科学决策具有重要意义。 在定量地测度科技进步对经... 随着当代科学技术的迅猛发展,科学技术进步对经济增长的作用受到普遍的重视。科学地测定科技进步的在经济增长中的贡献份额,对认识科技进步的现状和水平,把握经济增长方式的状况,进行科学决策具有重要意义。 在定量地测度科技进步对经济增长贡献的实证分析研究中,应用最为普遍的方法是美国经济学家罗伯物·索洛(Solow)提出的增长速度方程式法。该方法对科技进步的测定是以劳动的作用和资本的作用之外的“余值”进行的,因此,该方法提出后受到一些学者的质疑。但是, 展开更多
关键词 科技进步 速度方程式 贡献率 经济增长贡献 移动平均 生产函数 近似计算 几个问题 产出增长率 平均增长率
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天然气制合成气工艺基础〔下〕——甲烷转化反应动力学和游离碳析出的热力学
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作者 王德融 《天然气化工—C1化学与化工》 CAS 1980年第6期63-77,共15页
二、甲烷转化反应的动力学动力学的研究,特别是催化反应动力学的研究对于催化反应器的设计是很重要的。它可以剖析工业反应器中催化剂使用情况,逐步使设计和生产达到最佳化。同时,还可以分析各种因素对催化反应速度的影响,合理选择工业... 二、甲烷转化反应的动力学动力学的研究,特别是催化反应动力学的研究对于催化反应器的设计是很重要的。它可以剖析工业反应器中催化剂使用情况,逐步使设计和生产达到最佳化。同时,还可以分析各种因素对催化反应速度的影响,合理选择工业生产条件,并有助于探讨催化机理。但是,对于甲烷转化反应动力学的某些方面的研究至今还不太成熟,在压力下反应的研究文章较少, 展开更多
关键词 反应动力学 化学动力学 析碳 反应温度 甲烷含量 动力学方程式 化学反应速度方程式 克分子比 非均相反应 多相反应 热力学 游离碳 平衡常数 气压 甲烷转化 合成气 合成氨生产 天然气 混合气体
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Nonliner Analysis of a Synthesized Optimal Velocity Model for Traffic Flow 被引量:3
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作者 ZHU Wen-Xing JIA Lei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期505-510,共6页
We analyze a new car-following model described by a differential-difference equation with a synthesized optimal velocity function (SOVF),which depends on the front interactions between every two adjacent vehicles inst... We analyze a new car-following model described by a differential-difference equation with a synthesized optimal velocity function (SOVF),which depends on the front interactions between every two adjacent vehicles instead of the weighted average headway.The model is analyzed with the use of the linear stability theory and nonlinear analysis method.The stability and neutral stability condition are obtained.We also derive the modified KdV (Korteweg-de Vries) equation and the kink-antikink soliton solution near the critical point.A simulation is conducted with integrating the differential-difference equation by the Euler scheme.The results of the numerical simulation verify the validity of the new model. 展开更多
关键词 multi-interaction nonlinear analysis modified KdV equation SOVF
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Scholte wave dispersion and particle motion mode in ocean and ocean crust 被引量:1
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作者 Xu Xin Wan Yong-Ge +1 位作者 Li Zhen-Yue Sheng Shu-Zhong 《Applied Geophysics》 SCIE CSCD 2022年第1期132-142,146,共12页
The dispersion equation of the Scholte wave was reviewed using the homogeneous elastic half-space covered by a liquid layer,and the range of the Scholte wave propagation velocity was examined using the dispersion equa... The dispersion equation of the Scholte wave was reviewed using the homogeneous elastic half-space covered by a liquid layer,and the range of the Scholte wave propagation velocity was examined using the dispersion equation.The displacement expressions of the Scholte waves in liquid and solid were derived.Additionally,the mode of motion of Scholte waves in liquid and solid and their variation with depth was studied.The following results were obtained:The dispersion equation shows that the propagation velocity of the fundamental Scholte wave was greater than the P-wave in liquid and less than that of the Scholte wave in homogeneous elastic half-space.In contrast,the velocity of higher-order Scholte waves was greater than that of P waves in liquid and S-waves in solid.Only the fundamental Scholte wave has no cutoff frequency.The Scholte wave at the liquid surface moved only vertically,while the particles inside the liquid medium moved elliptically.The amplitude variation with depth in the solid medium caused the particle motion to change from a retrograde ellipse to a prograde ellipse.The above results imply the study of Scholte waves in the ocean and oceanic crust and help estimate ocean depths. 展开更多
关键词 Scholte waves in the ocean and oceanic crust dispersion equation propagation velocity amplitude mode of motion
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Kinetic Behaviors of a Competitive Population and Fitness System in Exchange-Driven Growth
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作者 LU Ke LIN Zhen-Quan SUN Yun-Fei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期105-110,共6页
We proposed an aggregation model of two species aggregates of fitness and population to study the interaction between the two species in their exchange-driven processes of the same species by introducing the monomer b... We proposed an aggregation model of two species aggregates of fitness and population to study the interaction between the two species in their exchange-driven processes of the same species by introducing the monomer birth of fitness catalyzed by the population, where the fitness aggregates perform self-death process and the population aggregates perform self-birth process. The kinetic behaviors of the aggregate size distributions of the fitness and population were analyzed by the rate equation approach with their exchange rate kernel K1(k,j) = K1kj and K2(k,j) = K2kj, the fitness aggregate's self-death rate kernel J1 ( k ) = J1 k, population aggregate's self-birth rate kernel J2( k ) = J2k and population-catalyzed fitness birth rate kernel I(k,j) = Ikj'. The kinetic behavior of the fitness was found depending crucially on the parameter v, which reflects the dependence of the population-catalyzed fitness birth rate on the size of the catalyst (population) aggregate. (i) In the v ≤ 0 case, the effect of catalyzed-birth of fitness is rather weak and the exchange-driven aggregation and self-death of the fitness dominate the process, and the fitness aggregate size distribution αk(t) does not have scale form. (ii) When v ≥0, the effect of the population-catalyzed birth of fitness gets strong enough, and the catalyzed-birth and self-death of the fitness aggregates, together with the self-birth of the population aggregates dominate the evolution process of the fitness aggregates. The aggregate size distribution αk (t) approaches a generalized scaling form. 展开更多
关键词 kinetic behavior aggregate growths catalyzed-birth rate equations
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Intelligent Machine Theory--A Key Approach to Initiate the Age of Designing Thinking Computers
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作者 Mustafa Pehlivan 《Journal of Mathematics and System Science》 2013年第8期417-418,共2页
The purpose of this paper is to introduce an unknown method for finding a real possible x value of any degree polynomial equation and to show how this can be applied to make computers which are at least x1000 (one th... The purpose of this paper is to introduce an unknown method for finding a real possible x value of any degree polynomial equation and to show how this can be applied to make computers which are at least x1000 (one thousand times) faster than today's existing highest speed computers. Since one of the Milennium Prize Problems offered by Claymath asks about whether P (Deterministic Polynomial) is equal to NP (Non-Deterministic Polynomial) (what that means informally is that whether we can design a computer which can quickly solve a certain complicated problem can also verify the solution quickly (and vice versa). Fortunately, the answer to P vs. NP problem based on my findings in certain algebraic algorythms is yes although there have been many people who claimed the answer is no. What that means is that humans can make machines that work very fast and close to human intelligence in the identification of, say, certain proteins and amino acids, in case my theory is proven to be a fact. This paper is therefore an initial stage of planting the first seeds of the process, in terms of describing how exactly this can happen, theoretically of course, since everything in Science begins with a theory based on the outcome of a hypothesis. 展开更多
关键词 FORMULA POLYNOMIAL equation x DEGREE function power solution milennium PRIZE problem
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Ultrasonic study on molecular interactions in binary mixtures of formamide with 1-propanol or 2-propanol
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作者 Manju Rani Suman Gahlyan +1 位作者 Ankur Gaur Sanjeev Maken 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第4期689-698,共10页
Ultrasonic speeds have been measured at 298.15 K and 308.15 K for mixtures of formamide + 1 -propanol or 2-propanol. For an equimolar mixture, excess molar compressibility follows the sequence of l-propanol 〉 2-prop... Ultrasonic speeds have been measured at 298.15 K and 308.15 K for mixtures of formamide + 1 -propanol or 2-propanol. For an equimolar mixture, excess molar compressibility follows the sequence of l-propanol 〉 2-propanol. The ultrasonic speed data are correlated by various correlations such as Nomoto's relation, van Dael's mixing relation and impedance dependence relation, and analyzed in terms of Jacobson's free length theory and Schaaffs collision factor theory. Excess isentropic compressibility is calculated from ex- perimental ultrasonic speed data and previously reported excess volume data. The excess molar ultrasonic speed and isentropic compressibility values are fitted to Redlich-Kister polynomial equation. Other proper- ties such as molecular association, available volume, free volume, and intermolecular free length are also calculated. The excess isentropic compressibility data are also interpreted in terms of graph theoretical ap- proach. The calculated isentropic compressibility values are well consistent with the experimental data. It is found that the interaction between formamide and propanol increases when hydroxyl group attached to a carbon atom has more -CH3 groups. 展开更多
关键词 Ultrasonic speedGraph theoretical approachFormamidePropanollntermolecular interaction
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苯的气相热裂非催化脱氢反应器的容积计算
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作者 罗明耀 何海兰 +3 位作者 孙碧秀 叶聪美 袁木琪 李恒铎 《浙江工业大学学报》 CAS 1977年第1期-,共5页
化工工艺设计的心脏部分就是要进行反应器的设计。一般是依据该反应的化学动力学速度方程式来进行反应器的基础计算,确定反应容积或其主要尺寸。所遇到的往往是常微分方程或方程组的初值问题,必须用近似方法计算。这种计算既费时、烦琐... 化工工艺设计的心脏部分就是要进行反应器的设计。一般是依据该反应的化学动力学速度方程式来进行反应器的基础计算,确定反应容积或其主要尺寸。所遇到的往往是常微分方程或方程组的初值问题,必须用近似方法计算。这种计算既费时、烦琐又欠精确。如果用电子计算机解算,不但节约了时间,而且由于缩小了步长,可以大大提高准确度。这次我们以苯的气相热裂(非催化)脱氢为例,进行等温管型反应器的计算,获得一定的成绩和经验。 展开更多
关键词 脱氢 管型 脱气 速度方程式 DX KI 裂纹 热裂 PT DT 联立方程 方程 气相 联苯烃 三联苯 BI AI AXI
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A divergence-free weak Galerkin method for quasi-Newtonian Stokes flows 被引量:4
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作者 ZHENG XiaoBo CHEN Gang XIE XiaoPing 《Science China Mathematics》 SCIE CSCD 2017年第8期1515-1528,共14页
This paper proposes a weak Galerkin finite element method to solve incompressible quasi-Newtonian Stokes equations. We use piecewise polynomials of degrees k + 1(k 0) and k for the velocity and pressure in the interio... This paper proposes a weak Galerkin finite element method to solve incompressible quasi-Newtonian Stokes equations. We use piecewise polynomials of degrees k + 1(k 0) and k for the velocity and pressure in the interior of elements, respectively, and piecewise polynomials of degrees k and k + 1 for the boundary parts of the velocity and pressure, respectively. Wellposedness of the discrete scheme is established. The method yields a globally divergence-free velocity approximation. Optimal priori error estimates are derived for the velocity gradient and pressure approximations. Numerical results are provided to confirm the theoretical results. 展开更多
关键词 quasi-Newtonian Stokes equation weak Galerkin method DIVERGENCE-FREE optimal error estimate
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