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11.
A formalism for studying the interference between the direct reaction and the compound resonance processes is presented by the S-matrix theory; The mechanism of 12C(d, d) 12C, 12C(d, p113C* and 12C(d, p213C* reactions in the energy range Ed=1.63 MeV to 2.05 MeV is analysed.Te results show that: the interference between these two processes exists; and the quantitative relation between them is given. While the parameters of direct reactions and compound resonance processes, particularly for four resonance states with Ed=1.726, 1.767, 1.792 and 1.86 MeV are determined.  相似文献   
12.
Energy levels of 209Po have been populated with the 210Po(d, t)209Po and 210Po(p, d)209Po reactions at bombarding energies of 17.0 and 17.8 MeV respectively. Fifteen levels were observed below 2.7 MeV of excitation. Energy levels of 211Po were populated with the 210Po(d, p)211Po reaction, also at 17.0 MeV. Thirty-five levels, almost all new, were observed below 3.9 MeV of excitation. Comparison of experimental angular distributions with DWBA calculations allowed l-value assignments and extraction of spectroscopic factors for many levels. In 209Po the observed level structure is well described in terms of a simple particle-vibration coupling model. In 211Po the level structure is more complex and the simple model is not adequate.  相似文献   
13.
As a continuation of a recent linear analysis by Mao et al.(Acta Mech Sin,2010,26:355),in this paper we propose a general theoretical formulation for the compressing process in complex Newtonian fluid flows,which covers gas dynamics,aeroacoustics,nonlinear thermoviscous acoustics,viscous shock layer,etc.,as its special branches.The principle on which our formulation is based is the maximally natural and dynamic Helmholtz decomposition of the Navier-Stokes equation,along with the kinematic Helmholtz decompos...  相似文献   
14.
微积分是理工科大学生的一门非常重要的基础课.给出了微积分中求未定式极限时需注意采取的一个措施及由微分方程的通解求相应的微分方程的一般方法,并给出了算例.  相似文献   
15.
The objective of this study is to synthesize ZnO and Mg doped ZnO (Zn1−xMgxO) nanoparticles via the sol-gel method, and characterize their structures and to investigate their biological properties such as antibacterial activity and hemolytic potential.Nanoparticles (NPs) were synthesized by the sol-gel method using zinc acetate dihydrate (Zn(CH3COO)2.2H2O) and magnesium acetate tetrahydrate (Mg(CH3COO)2.4H2O) as precursors. Methanol and monoethanolamine were used as solvent and sol stabilizer, respectively. Structural and morphological characterizations of Zn1−xMgxO nanoparticles were studied by using XRD and SEM-EDX, respectively. Photocatalytic activities of ZnO and selected Mg-doped ZnO (Zn1−xMgxO) nanoparticles were investigated by degradation of methylene blue (MeB). Results indicated that Mg doping (both 10% and 30%) to the ZnO nanoparticles enhanced the photocatalytic activity and a little amount of Zn0.90 Mg0.10 O photocatalyst (1.0 mg/mL) degraded MeB with 99% efficiency after 24 h of irradiation under ambient visible light. Antibacterial activity of nanoparticles versus Escherichia coli ( E. coli ) was determined by the standard plate count method. Hemolytic activities of the NPs were studied by hemolysis tests using human erythrocytes. XRD data proved that the average particle size of nanoparticles was around 30 nm. Moreover, the XRD results indicatedthat the patterns of Mg doped ZnO nanoparticles related to ZnO hexagonal wurtzite structure had no secondary phase for x ≤ 0.2 concentration. For 0 ≤ x ≤ 0.02, NPs showed a concentration dependent antibacterial activity against E. coli . While Zn0.90Mg0.10 O totally inhibited the growth of E. coli , upper and lower dopant concentrations did not show antibacterial activity.  相似文献   
16.
1 IntroductionInrecentyears,theintentionaloraccidentalreleaseofthechemicalwastesonsoilshasfurtherstimulatedcurrentinterestsinthemovementofchemicals.Displacementstudieshavebecomeimportanttoolsinsoilphysics,particularlyforpredictingthemovementofpestcides…  相似文献   
17.
本文对钕玻璃的光泵感应热畸变作了理论分析,给出了光泵感应热畸变与钕玻璃热光性质的关系,并对高重复率脉冲器件和单次脉冲器件作了热畸变的定量测量,实验结果在一定程度上与理论分析相符。  相似文献   
18.
Simulations of the gas fluidization of a cohesive powder were performed using the Stokesian Dynamics method and an agglomeration-deagglomeration model to investigate methods of improving the fluidizability of fine powders. Three techniques (a) high gas velocity (b) vibration-assisted fluidization and (c) tapered fluidizer were used in the simulations which provided detailed information on the bed microscopy such as the motion of 1 O0 particles in a fluidizing vessel along with the formation and destruction of cohesive bonds dudng collisions. While all three techniques were found to effectively improve the fluidizability of a strongly cohesive powder, we suggest a combination of high velocity fluidization assisted by extemal vibration of the fluidized bed to minimize entrainment of particles.  相似文献   
19.
微量量热法研究温度对两种石油菌生长的影响   总被引:1,自引:0,他引:1  
本文采用微量量热法测定了两种石油菌在不同温度下的生长热谱图. 按限制性条件下微生物生长模型 ,用三点法进行了数学处理, 得出了生长速率常数(k) ; 计算机拟合 k-T 非线性方程,得到了石油菌 I,II的最佳生长温度( To pt)分别为 322. 07K 和 322. 85K. 按阿仑尼乌斯公式和过渡态理论计算得到有关热动力学函数, 并根据所得结果对两种石油菌的生长代谢过程进行了热动力学分析.  相似文献   
20.
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