首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
用单脉冲激波管研究了全氟丙烯C3F6的分解。使用H2作为清扫剂。产物包括CH4、C2F4、CF3H和C2F3H4,作为对断键反应过程的指示。C3F6的断键反应为C3F6→CF3+C2F3(1)得到其速率常数表达式为k(C3F6→CF3+C2F3)=10^(17.4±0.2)exp(-355300±8360/RT)s^^-1温度范围为1090K〈T〈1190K。全氟丙烯上,乙烯基C-CF3键的解离能为355.3kJ/mol。C3F6生成焓值为-1078.4kJ/mol。  相似文献   

2.
α-环糊精包合物中环己烷构象平衡的PM3研究   总被引:1,自引:0,他引:1  
用PM3分子轨道方法研究了α-环糊精的包合作用对怀烷构象平衡的影响。发现α-环糊精的包合作用可以改变环己烷的构象平衡。计算结果表明,虽然环己烷的椅式构象比船式构象稳定18.5kJ·mol^-1,但在α-环糊精的包合物中,船式环己烷包合物比椅式环己烷包合物稳定4.4kJ·mol^-1。因此,超分子体系中客体分子的构象平衡不能简单地从其游离态的构象平衡外推得到,而应该考虑在超分子体系中分子间相互作用对  相似文献   

3.
本文利用流动余辉技术研究了亚稳态原子He(2^3s)和Ne(^3p0.2)与POCl3分子的传能反应,获得了激发态碎片PO(A)和PO(B)的发射光谱,测定了He(2^3s)与POCl3反应中PO(A)和PO(B)的形成速率常数,其数值分别为:KPO(A)=3.68×10^-11cm^3·molecule^-1S^-1和KPO(B)=9.40×10^-11cm^3·molecule^-1·S^-1  相似文献   

4.
CO(a)与CS2和CS传能反应中激发态碎片形成速率   总被引:1,自引:0,他引:1  
本文利用流动余辉技术研究了亚稳态CO(a)与CS2和CS的传能反应,测定了反应产生的激发态碎片CS(A)和CS(a)的形成速率常数。CO(a)与CS2传能反应中CS(A)和CS(a)的形成速率常数分别为3.46×10^-11cm^3·molec^-1·sec^-1和1.14×10^-10cm^3·molec^-1·sec^-1。CO(a)与CS传能反应中CS(A)和CS(a)的形成速率常数分别为1  相似文献   

5.
基于多体项展式方法所导出的NeH2^+(^2Σ^+)的分析势能函数,用准经典的Monte-Carlo轨迹法研究了Ne+H2^+(v)→NeH^++H、Ne+H2^+(v)→Ne+H+H^+和NeH^++H→H2^++Ne的反应动力学。研究表明,前两个反应在H2^+的初始振动基态时的反应阈能分别为16kcal·mol^-1和62kcal·mol^-1,反应阈能随振动量子数增大而减小。最后一个反应是无  相似文献   

6.
P538萃取锰(Ⅱ)的研究   总被引:1,自引:0,他引:1  
在25±0.5℃,用P538的环己烷溶液从NaClO4-HClO4介质中萃取Mn(Ⅱ)的反应机理为离子交换机理,萃取焓△H=-196kJ.mol^-1并用Cl^-离子水合作用和Mn^2+与Cl^-形成配合物的竞争解释了萃取分配比与水相中NaCl浓度的关系。  相似文献   

7.
本文用280nm脉冲激光光解被Ar和Xe基体隔离的Fe(CO)5以产生配位不饱和的Fe(CO)3。用傅里衰变换红外光谱仪实时监察光解停止后Fe(CO)3和CD的复合,并以Smoluchowski扩散控制反应动力学理论模型求得Fe(CO)3与CO的反应半径为4.0×10^-10m,CO在10K的Ar和Xe基体中的扩散系数分别为2.2×10^-23m^2/s和4.5×±∩^-23m^2/s。  相似文献   

8.
在激波管上用反射激波加热气体使之变化,绾炎以强稀疏波快速冷却,造成电离非平衡状态,构成一种新的电离复合动力学实验研究方法。测定了温度在3100-3700K范围内NO^+离子与电子的解离复合速度常数:k^+r=5.5×10^17T^-.52cm^3mol^-1s^-1。  相似文献   

9.
本文在束-气条件下研究了亚稳态原子He(2^3S)与CH2Cl2间的传能反应,测得了由该反应产生的CH(A^2△-X^2П),CH(B^2∑^-X^2П)CH(C^2∑^+-X^2П)和H原子(Balmer系)的化学发光光谱。通过对CH(A,B)的光谱进行计算机模拟,推测出初手的CH(A^2△,v^1=0-2)态振动分布为No:N1:N2=100:40±5:19±2,CH(A^2△,v^1=0-0  相似文献   

10.
本文讨论了利用计算机模拟技术研究传能产物振动布层的理论和方法。以Ar(^3P0.2)+PCl3反应生成PCl(A^3П)为例,对模拟的过程和其中应注意的问题进行了分析。文中首次报道了PCl(A^3П→X^3Σ^-1)跃迁的Franck-Condon因子。  相似文献   

11.
Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.  相似文献   

12.
A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.  相似文献   

13.
The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.  相似文献   

14.
15.
A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.  相似文献   

16.
Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·104 Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.  相似文献   

17.
A transient suppression method for piezoelectric ceramic transducer is presented. By adding some special pedestal pulses to the original transmitted signal, the transient effects in the output of the transducer can be just precisely transmission by use of a narrowband transducer. canceled, thereby achieving the broadband The experimental results show that the transient responses of the sinusoid pulses and coded signals are suppressed successfully and the acoustic waveforms radiated into the surrounding water are improved significantly.  相似文献   

18.
We experimentally demonstrate amplitude squeezed soliton utilizing intensity-dependent self-phase modulation in an asymmetric Sagnac interferometer.The system.whose components are connected via ferrule connector/physical connection(FC/PC)fiber connectors,constitutes all-fiber configuration to generate squeezed soliton.Soliton amplitude reduction measured by homodyne detection is near 4.0 dB below the shot-noise level.Optimal squeezing fields in both simple and compact all-fiber configuration are obtained.  相似文献   

19.
The(2 1)-dimensional nonlinear Schr(o)dinger(NLS)equation with spatially inhomogeneous nonlinearities is investigated,which describes propagation of light in(2 1)-dimensional nonlinear optical media with inhomogeneous nonlinearities.New types of optical modes and nonlinear effects in optical media are presented numerically.The results reveal that the regular split of beam can be obtained in (2 1)-dimensional nonlinear optical media with inhomogeneous nonlinearities,by adjusting the guiding parameter.Furthermore,the stability of beam regular split is discussed numerically,and the results reveal that the beam regular split is stable to the finite initial perturbations.  相似文献   

20.
In the real-world application of face recognition system, owing to the difficulties of collecting samples or storage space of systems, only one sample image per person is stored in the system, which is so-called one sample per person problem. Moreover, pose and illumination have impact on recognition performance. We propose a novel pose and illumination robust algorithm for face recognition with a single training image per person to solve the above limitations. Experimental results show that the proposed algorithm is an efficient and practical approach for face recognition.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号