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Classical trajectories were run on a local fit to the bifurcating transition region of the Valtazanos and Ruedenberg ab initio potential energy surface for the cyclopropylidene to allene reaction, and also on several variations of this local surface. The trajectory results were analyzed to determine the outcome as a function of initial conditions, and several plots of these are presented.Camille and Henry Dreyfus Teacher-Scholar; Alfred P. Sloan Foundation fellow 相似文献
113.
Hongbo S Zongsuo L Mingan S Shimeng S Zanmin H 《Colloids and surfaces. B, Biointerfaces》2005,43(3-4):221-227
Drought is a worldwide problem, seriously influencing plant (crop) productivity. Wheat is a stable food for 35% of the world population, and moreover, about 60% of land area on the globe belongs to arid and semiarid zone. Wheat drought resistance is a multi-gene controlling quantitative character and wheat final production in field is realized mainly by physiological regulation under the condition of multi-environmental factor interaction. Exploring drought resistance physiological mechanisms for different wheat genotypes is of importance to finding new drought resistance gene resources and conventional breeding, and the basis for wheat drought resistance biotechnological breeding and platform. Photosynthesis is the main component for physiological machinery of wheat assimilates conversion and wheat production. Investigation on photosynthetic characteristics of different wheat genotypes at soil water deficits also has other implications for refine physiological regulation of photosynthesis in fields and field management of crops in arid and semiarid areas. By pot-cultivating experiments, investigation of photosynthesis for 10 wheat genotypes at seedling stage and tillering stage at soil water deficits (75%FC, 55%FC and 45%FC, respectively) was conducted. The main results were as followed: developmental stages influenced wheat photosynthesis greatly and tillering stage played more roles; there were significant difference in the main photosynthetic parameters, photosynthesis rate (Photo), stomatal conductance (Cond) and transpiration rate (Tr), among 10 wheat genotypes; general photosynthesis and drought resistance in different wheat genotypes was related much to their domesticated origin soil water environment and selected generations and there was a photosynthetic threshold effect in terms of different wheat genotypes at soil water deficits. 相似文献
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《Applied Mathematical Modelling》2014,38(7-8):2037-2050
The elevator system driven by a permanent magnet synchronous motor (PMSM) is studied in this paper. The mathematical model of the elevator system includes the electrical and mechanical equations, and the dimensionless forms are derived for the purpose of practicable upward and downward movement. In this paper, the trapezoidal, cycloidal, five-degree (5-D) and seven-degree (7-D) polynomial and industry trajectories are designed and compared numerically in various motion and the absolute input energies. From numerical simulations, it is found that the trapezoidal trajectory consumes the minimum energy; the 7-D polynomial trajectory consumes the maximum one. The less end-point constraints are required, the less energy is consumed. Finally, the proposed sliding mode controller (SMC) is employed to demonstrate the robustness and well tracking control performance numerically. 相似文献
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In this Letter the evolution of a single photon and collective effect of a photon system in background plasma waves are uniformly described in the framework of photon dynamics. In a small-amplitude plasma wave the modulation of photon dynamical behavior by the plasma wave can be treated as perturbation, and photon acceleration effect and photon Landau damping are investigated in linear theory. In an arbitrary-amplitude plasma wave, photon evolution trajectories in phase space are obtained by solving dynamical equations, and photon trapping effect and motion equations in the given plasma wave are also discussed. 相似文献
119.
目的比较显微镜下单纯翼状胬肉切除与切除后联合角膜缘干细胞移植两种手术方式对老年静止期翼状胬肉患者的治疗效果.方法将>65岁的原发性静止期翼状胬肉患者随机分为两组,A组行显微镜下单纯翼状胬肉切除术,B组在翼状胬肉切除后行自体角膜干细胞移植,术后随访6~36个月(平均10个月),观察手术时间及术后复发情况.结果 A组手术时间(14.2±1.3)min,明显短于B组(24.1±1.2)min,比较有统计学差异(P=0.000).而复发率比较,A组复发率6.67%(2/30),B组复发率3.33%(1/30),两组间无统计学差异(P=0.550).结论两种手术复发率均较低,但单纯切除术手术时间短,对不能长时间耐受手术或手术配合度较差的老年静止期翼状胬肉患者,可以作为首选手术方式. 相似文献
120.
Dr. Lucas Frédéric Bibiana Fabri Dr. Laure Guénée Dr. Francesco Zinna Prof. Lorenzo Di Bari Prof. Jérôme Lacour 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(56):e202201853
In essentially one-pot, using Ir- and Pd-catalysis, tris(arene)-functionalized cationic [4]helicenes are synthesized with full regioselectivity and enantiospecificity starting from a trivial precursor (17 examples). This poly-addition of aryl groups improves key optical properties, that is, fluorescence quantum yields and lifetimes. Electronic circular dichroism and circularly polarized luminescence signatures are observed up to the far-red domain, in particular with additional arenes prone to aggregation. 相似文献