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1.
In binary phase diagram there are many stable compounds. Hereby a new method for calculating activities of compounds from binary phase diagram involved stable compounds is presented. Based on the available formula for calculating activities in binary phase diagram, the activities of the two pure components are gained. And the balance constant K~0 can be obtained from mass action law. Thereby, the activities of stable compounds are obtained from the activities of the two pure components. By using this method, the activities of stable compounds in In-Sb system are obtained. It proves that this method is feasible. 相似文献
2.
The authors calculate the cross-section with one-loop electroweak corrections to electron-positron pair production via two photon collisions in the standard model (SM), including virtual corrections and soft photon radiative correction. The relations between the cross-sections are discussed in tree level (and one-loop corrected cross sections) and center-mass energy in the luminosity measuring ranges of GLC. At last, the authors acquire the relation curves between differential cross section and the outgoing electron angle. 相似文献
3.
辽河流域水环境预警研究 总被引：3，自引：1，他引：2
建立科学的预警系统是解决中国水环境危机的重要手段,为解决正确、快速而又直观预警的问题,引申并利用韦伯-费希纳定律,结合熵权法,以辽宁段内的三合屯、阿吉堡作为研究实例,选取与辽河流域水环境关系密切的水质评价指标。在此基础上利用熵权法确定各指标的权重,计算2个断面的水环境预警值,进而建立水环境质量等级与水环境综合影响指数之间的水环境预警模型。结果表明：三合屯预警级别为超重警,阿吉堡为无警,此模型可以较好地用于辽河流域水环境预警与评价。 相似文献
4.
为探究大攻角及桥面粗糙度对扁平钢箱梁涡振性能的影响,对寸滩长江大桥主梁进行了风洞试验。应用Matlab软件模拟桥面粗糙度变化范围,根据模拟结果选取对应的砂纸在试验中模拟桥面粗糙度,分析了攻角及桥面粗糙度对扁平钢箱梁涡振区间及幅值的影响。试验研究表明:在大攻角下扁平钢箱梁的涡振振幅和范围明显增大,对桥址位于山区等容易发生大风攻角的地区的桥梁应进行大攻角试验。扁平钢箱梁的涡振响应随着桥面粗糙度增大而减小。正攻角范围内,桥面粗糙度对涡振响应的影响随着攻角减小而增大。桥面粗糙度发生变化时,扭转涡振响应更加敏感,变化幅度大于竖向涡振响应变化幅度。 相似文献
5.
A section algorithm of reliability evaluation for complex medium voltage Electrical Distribution Networks (EDNs) using adjacency multilist (AM) is proposed. The constructing method for AM is introduced. The AM can be used to store the structure data of EDNs and to solve the problem of space & time complexity. A new power flow algorithm of backward / forward sweep is proposed and a fast algorithm of forming sections in distribution network is put forward. The proposed algorithm makes a perfect combination of the power flow algorithm and the section algorithm of reliability evaluation, which makes efforts to decrease the work of programming and saves the computing time. Applying the proposed algorithm in RBTS-BUS6 system and actual EDNs, the reliability assessment results show that the algorithm has an advantage of saving time and possesses efficiency in engineering practicality. 相似文献
6.
《Journal of Landscape Research》2017,(4)
This paper, based on the statistical data from the Sample Survey of Domestic Tourism in Inner Mongolia(2014), analyzed the distribution of the domestic tourism market across Inner Mongolia and its 4 tourism sections through indexes including market concentration ratio, geographic concentration ratio, variance, etc.. The results showed that:(1) the market within the autonomous region remained to be the largest one in those 4 sections;(2) Beijing was the largest domestic tourism market outside Inner Mongolia;(3) different sections were divided on the target market of domestic tourism:(1) Beijing-Tianjin-Hebei Region proved to be the primary market of Inner Mongolia at large;(2) Beijing and 3 provinces in Northwest China came as the primary markets of Hulun Buir-Hinggan section;(3) Beijing-Tanjin-Hebei Region and Liaoning Province were the primary markets of Xilingol-Chifeng-Tongliao section;(4) BeijingShanxi-Hebei Region turned out to be the primary market of Huhhot-Baotou-Erdos-UlanqabBayannur section;(5) Beijing and Gansu were the primary markets of Wuhai-Alxa section;(4) the market concentration ratio of domestic tourism in different sections varied from each other, and the east section was the highest one, followed by middle section, Inner Mongolia as a whole, west section, and northeast section. As a result, authors of this paper made recommendations on how to develop the domestic tourism in Inner Mongolia. 相似文献
7.
Because of the high altitude of Qinghai, its air pressure is 0.77 atm which is lower than the atmospheric pressure. Therefore, an analysis is done for carbochlorination reaction of flyash for the extraction of aluminum in such an environment. The phase diagrams and predominance area diagram on chlorides are calculated and drawn and the equilibrium compositions of complex system composed of multi-components are simulated by Factsage software. Results show that, carbochlorination reaction converts Al2O3 and SiO2 which can not directly react with chlorine gas originally to chloride completely, and this demonstrates the thermodynamics feasibility of carbochlorination process. The ratio of FeCl3(Fe2Cl6) to FeCl2 changes with the amount of carbon and chlorine gas. The catalysts like Na2CO3, CaCO3 and B2O3 have some side effects in the aspect of thermodynamics such as consuming chlorine gas and carbon. The volatility of AlCl3(Al2Cl6) is affected by other chlorides. Compared with the normal pressure region, there are advantages and disadvantages to carbochlorination reaction under the pressure below the normal. The work provides thermodynamic data for the process. 相似文献
8.
A new method with which to calculat the displacements of beams and frames is presented. The areas of tending moment diagram of beam or frame and the slope at the origin of the elastic curve are treated as some rotatable vectors with this method. Angular displacement and in-line displacement can be calculated by using the projection and moment of these vectors. This method can be used to calculate displacement of the bar and the bar syttem ( including three dimensional forms. ) , which made from linear or ncnlinear elastic materials. The cross section of the bar is changeable. 相似文献
9.
山西省2011年11月28-29日暴雪天气过程诊断分析 总被引：1，自引：1，他引：0
为了深入研究山西产生暴雪天气过程的环流背景、影响系统及在强降雪期间物理量场空间结构的有利配置,针对2011年11月28-29日山西区域性暴雪天气过程,从500 hPa环流背景、中低层影响系统的相互配置、fy-2c红外卫星云图的演变特征、物理量场（垂直速度、散度、相对湿度）的空间垂直剖面进行了综合分析。结果表明：该次暴雪天气过程是在500 hPa西风槽、700 hPa切变与850 hPa持续偏东风的共同作用下形成,700 hPa切变与fy-2c云图上云团的演变过程息息相关,尤其位相变化一致,构成了暴雪产生的直接影响系统,强烈的上升运动,深厚湿层、上散下合流畅配置构成了强降雪产生的有利条件。该次暴雪天气过程的综合分析研究,给出了今后暴雪预报具有指导性意义的参考信息。 相似文献
10.
Experimental Analysis on the Mechanical Properties of Concrete Composite Slabs with Precast Prestressed Rectangular Rib Panels 总被引：1，自引：0，他引：1
For the convenience of industrialized production and site operation,specification design of PPCRP (precast prestressed concrete ribbed panels) is discussed. In order to obtain ultimate bearing capacity,bending rigidity and crack resistance,four PPCRP with two types of spans are studied,and the results show that PPCRP can satisfy the requirements of bearing capacity in construction phase and can serve as stay-in place formwork. To verify the mechanical property,shear behavior on contact interface of composite member and moment redistribution factor of continuous composite member,two single-span composite members and one two-span continuous composite member are studied. It is indicated that computational method for bearing capacity of composite member can be the same as cast-in-situ concrete slab. Besides,section strain analysis for composite member in two-loading is conducted,which suggests that thickness of bottom board can be used as calculated height with the consideration of two-loading. 相似文献
11.
In this paper,the stability problems of coal and rock mass exerted by horizontaland vertical forces are studied with the help of the method of catastrophic theory. The expression ofthe total potential energy function for this system is derived. This system can be described by thecusp catastrophe model. The bifurcation set which makes this system to loss its stability in the hori-zontal and vertical force control space is obtained. At the same time ,the process of Sudden statechange of coal and rock due to the changes of horizontal and vertical forces is discussed. 相似文献
12.
为了探究ECC/高强钢筋混凝土叠合梁的正截面受弯特征,以及ECC层厚度对叠合梁整体受弯性能的影响,做了两组共5根梁试件的正截面受弯试验。发现与高强钢筋混凝土梁相比,叠合梁的承载力更高,相同荷载下的挠度值和最大裂缝宽度较小。在受弯全过程中其截面应变仍符合平截面假定,钢筋与ECC也可以实现协调变形,说明受拉区使用ECC可以使得高强钢筋的应力得到充分发挥。但ECC层厚度过大可能会使叠合梁发生脆性破坏。进一步地,在此研究的基础上,对已有ECC的本构模型进行简化,忽略其应力强化贡献,并运用叠加原理,提出一种用于计算ECC/钢筋混凝土叠合梁正截面受弯承载力的方法,将计算结果与试验结果及诸多文献结果进行比较,发现吻合度较高。 相似文献
13.
《Netherlands Journal of Sea Research》1989,23(3):239-253
In the partially mixed part of the Volkerak Estuary current speed and salt concentration are measured in several stations for periods of 13 hours on August 16 and 17, 1977. The freshwater discharge on those days and during the preceding six months is kept constant at a rate of 50 m3·s−1. In spite of different wind conditions, the longitudunal distribution of the tidally- and cross-sectionally averaged salt concentration is the same for both days. The vertical structure of circulation and salt concentration differ significantly. A similar set of measurements is carried out on March 18, 1980 with a constant freshwater discharge of 100 m3·s−1. The doubling of freshwater discharge leads to a relatively small increase in vertical circulation and stratification.In this study, the vertical circulation and stratification is examined in terms of the external forcings, freshwater discharge and wind, with special emphasis on wind. Tide conditions, for the three measurement days are similar. The estuary is schematized to a prismatic channel with a rectangular cross-section. In the schematized channel the tidally averaged salt concentration and velocity distribution are laterally uniform. To account for salt fluxes in the actual estuary associated with lateral and time-variations in current velocity and salt concentration, a diffusive salt flux is introduced. The effect of wind and longitudinal density gradients on the vertical circulation and stratification in the schematized channel is investigated using a simplified form of the two-dimensional conservation of momentum and salt equations. Using observed values along the axis of the estuary a scaling analysis shows that in the two-dimensional conservation of momentum equation the longitudinal pressure gradient and horizontal turbulent shear are the dominant terms, closely followed by the tidal stress. In the conservation of salt equation, the dominant terms are those associated with advective fluxes resulting from the horizontal and vertical tidal mean velocities, a horizontal flux associated with tidal variations in the longitudinal velocity and salt concentration and the vertical turbulent flux. Retaining only first order terms, the equations are solved using the similarity solution of Hansen and Rattray. Comparing calculated and observed vertical circulation and stratification it is shown that wind mixing significantly increases the vertical exchange of momentum, thereby reducing the density-driven vertical circulation (=gravitational circulation) and stratification. At the same time, through the wind surface stress, wind generates its own vertical circulation and, therefore, stratification. An expected increase in vertical exchange of mass with increasing wind speed and accompanying reduction in stratification could not be confirmed by the analysis. It is concluded that on the days of the measurements wind is as important as the longitudinal salt concentration gradient in forcing vertical circulation and stratification. Care should be taken in generalizing this conclusion as on the days of the measurements the axial component of the wind velocity is always in the down estuary direction. 相似文献
14.
为研究温室内两种爵床科植物叶片解剖结构及光合特性,本试验选取青岛世界园艺博览会植物馆内的两种爵床科植物,赤苞花(Megaskepasma erythrochlamys Lindau)、黄虾花(Pachystachys lutea Nees)为研究对象,用石蜡包埋法对两种植物的叶片进行解剖分析,使用CIRAS-3便携式光合仪测定其光合特性。结果表明,爵床科的两种植物在相同的环境中,叶片的内部结构相似,上表皮均厚于下表皮,海绵组织均厚于栅栏组织。光合指标存在差异,赤苞花的蒸腾速率、气孔导度、细胞间CO2浓度均大于黄虾花,但黄虾花的水分利用率、净光合速率大于赤苞花。 相似文献
15.
费约果花芽石蜡切片技术的改良 总被引：1，自引：1，他引：0
为获得用石蜡切片方法观察费约果花芽形成和分化的整个过程的最优条件,选择了3 个不同发育时期的花芽进行石蜡切片技术研究。以常规石蜡切片方法为基础,在固定、软化、脱水、透明、包埋以及染色等具体方法上进行了适合费约果花芽特点的改良。结果表明：对材料进行24 h 盐酸水溶液浸泡法进行软化后,采用优化后的一系列脱水、透明等步骤进行制片操作,可以得到连续的、完整的蜡带;最终获得切片通过显微观察,可见材料内部结构完整、染色清晰。优化后的石蜡切片技术,避免了常规制片过程中出现浸蜡不彻底、组织变硬变脆、蜡带不连续、内部结构不完整等问题。该研究为费约果石蜡切片技术提供了一套具体的操作步骤,同时也为与费约果花芽结构相似树种的研究提供技术参考。 相似文献
16.
The dynamic behavior of railway bridges (dynamic deflection and acceleration) is one of the running safety control indices for high speed trains. Therefore, the dynamic behavior of railway bridges is studied based on the concept of the dynamic signatures of the train and the bridge. By simplifying the train excitation as a series of moving concentrated forces, the mathematical expressions of the dynamic signatures of the train are obtained through theoretical derivations, and then a method is presented for calculating the resonance speed of trains and the maximum vertical acceleration of the bridge. With this method, the dynamic responses of the simple supported bridge can be calculated quickly. The feasibility of this method is validated through some examples, in which the resonance mechanism of train bridge system and the influencing factors are investigated. In addition, the effect of high frequency components to the bridge acceleration is also analyzed. 相似文献
17.
Summary Aspects of selection for yield and harvest index were investigated by simulating selection using data from random pedigreed F2, F3, F4 and F5 derived lines from two crosses grown in plots at two sites over two years.Improvement in yield through selection was obtained when the response was measured at the same site and in the same year as the selection. Selecting the best 10 per cent of F2 to F4 derived lines gave F5 derived lines that outyielded random selections by 19 to 53 per cent for one cross and 5 to 23 per cent for the second cross. These lines were 41 to 50 per cent better than the mid-parent in one cross, but were less than the mid-parent in the other cross.However, the response to selection when measured in a different year was little better than random selection. The effect of different sites also reduced the effectiveness of selection.Selection of harvest index in early generations for improvement of yield was ineffective when response was measured at the same site in the same year, or in different years.Contrary to some theoretical proposals, the same improvement in yield was obtained by selecting in early or late generations. While high yielding genotypes may be lost by delaying selection, this is counteracted by the better predictive value of late generations due to their greater homozygosity and homogeneity. 相似文献
18.
According to scattering theory, the lowest order cross section between nucleons is calculated. Besides, based on the Great Moment Integral Limitation and the Complex Function Integral Method, the corrected cross section is obtained by treating the pion propagator with chain approximation. The experiment results show that perturbation theory can be used to deal with strong interaction. 相似文献
19.
Morphologies of precipitation phases along grain boundary of the as-cast Mg-6.0Zn-0.45Zr, Mg-6.0Zn-(1.2Y) and Mg-6.0Zn-0.6Zr-1.0Y alloys are studied by using the methodologies of metallurgical phase analysis, scanning electron microscopy(SEM) analysis and energy diffraction x-ray(EDX) analysis. The experimental result indicates that the main precipitation phases along grain boundary of the as-cast alloys Mg-6.0Zn-0.45Zr is Mg-Zn binary phase. There are two kinds of precipitation phases along grain boundary for Mg-6.0Zn-1.2Y and Mg-6.0Zn-(0.6)Zr-1.0Y alloys. One grew at triangular grain boundary, which is fish-bone -like and contained Mg-Zn binary phase and Mg-Zn-Y ternary phase. The other distributed mainly around the grain, which is net-like and contained Mg-Zn-Y ternary phase. In addition, there are lots of granular phases, extending to the interior of the grain, at the rim of grain boundary phases. Finally, Y can intensively change morphology of precipitation phases along grain boundary of the as-cast Mg-Zn-Zr alloy (ZK60) alloys. 相似文献
20.
In this paper, according to the conception of rotation of the section orthographic projection around a fixed axis, the element stiffness matrix of thin-walled beam is directly deduced and the direct stiffness method is used to solve the continuous beam problem with different shear centers on one section. It is suggested through an example that when the element flexibility matrix and force method are used to solve the same question, the same answer will be gained, but the method used in this paper is simpler. 相似文献