[Co^I(CO)(dppe-P,P')2]2[Co2^I^I(μ-dppeo)Cl6].2CH3OH的合成和结构

合成了混合价态多核羰基钴离子对配合物[Co^I/(CO)(dppe-P,P')2]2[co2^I^I(μ-dppeo)Cl6]{dppeo=双二苯基膦基乙烷Ph2P(O)CH2CH2P(O)Ph2},用X射线衍射法测定了其晶体学参数为a=11.761(3),b=12.860(2), c=21.428(3)A, a=81.45(2), β=82.47(2), γ=79.84(2)°, 三斜晶系, PI空间群, Co^I和Co^I^I具有不同的配位构型, 量子化学计算结果解释了该配合物稳定的原因。     

Study of the Reaction Mechanisms Induced by 16O on 64Ni at 96MeV

The angular distributions and Wilczynski plots of emitted fragments from He to O in reaction of ¹⁶O+⁶⁴Ni at 96MeV have been measured.The DIC cross section and intereaction time were obtained.DIC character of the reaction was discussed.The trace which shows that the emitted fragments of He and Li mainly come from the evaporation process of compound nuclei emerged.     

The Study of α Emission Induced by 46.7MeV/u 12C on 58Ni、115In and 197Au

The energy spectra and angular distribution of α particles emitted from ¹²C induced reactions with ⁵⁸Ni,¹¹⁵In and ¹⁹⁷Au have been measured.Three moving sources of emitting α particle are clearly seen from invariant cross section distribution in velocity coordinates.The experimental data were analyzed by using three moving sources.Extracted parameters of the source with half-beam velocity are in agreement with the systematic values from Fermi Gas Model.The energy spectra and the extracted parameters for various targets are discussed.The low energy peak in energy spectra is possibly from the emitted α particle from equilibrium system after pre-equilibrium emission of target-like products.The energetic α particles are mainly from projectile fragmentation and projectile-like fragmentation.     

STUDY OF THE TIMING PERFORMANCE OF A LARGE AREA PLASTIC SCINTILLATION COUNTER FOR TOF MEASUREMENT

A large area plastic scintillation counter (80×10×1cm²) for TOF measurement has been made and the timing performance of this system has been measured. Various effects on the timing performance have been studied.     

A new method of controlling chemical chaos——Nonlinear artificial neural network (ANN)-occasional perturbation feedback control in the whole chaotic region

A new method of controlling chemical chaos to attain the stabilized unstable periodic orbit (UPO) is proposed. It is an extension of the occasional proportional feedback (OPF) control strategy which spans the limitations of OPF, i.e. the linear region of the control rule, and extends to the whole chaotic region. It also expresses the nonlinear control rule with the back propogation-artificial neural network (BP-ANN) in order to increase the robustness of the control. Its effectiveness is examined through controlling an autocatalytic chaotic reaction model numerically.     

叶轮与叶片扩压器相干非定常流动的数值模拟

本文采用了不对粘性项作任何近似的时间倾斜算子,来处理转子和静子栅距不相等时的周期性边界条件施加时所出现的问题。对某一离心压缩机进行了非定常的数值模拟,并把其结果同实验测量数据和商用软件的结果进行了比较。结果表明两种非定常计算方法比定常计算结果更接近于实验测量值,定常的计算结果在某些测量平面上不能充足地预测出流场结构,本文所发展的时间倾斜算子的计算程序在总体上同实验测量结果吻合最好,应用其能很好地预测离心压缩机级的非定常流动。     

废旧碱性电池水热法制备纳米晶锰锌铁氧体的研究

以废旧碱性电池为原料采用水热法制备出了纳米晶锰锌铁氧体,并对制备过程的影响因素进行了探讨,借助于XRD、TEM等手段对制备过程跟踪检测,并对产物进行了表征。结果表明,适宜的制备条件为:溶液pH值为10.0,水热温度为180℃,水热时间为4h,采用逆加料方式和加入冰乙酸作为添加剂均可制得粒径更小、分散性更为优良的纳米晶,产物粒径可达17nm左右。     

汽油中有机硫化物的酸富集和结构分析

石油中发现的硫化物已超过250种,其中约有1／4存在于汽油中。由于汽油中每种硫化物的含量都很低,又有十分复杂的烃组分和含氮组分的干扰,单纯使用仪器方法对汽油中的有机硫化物进行结构分析是十分困难的。通常的做法是对汽油样品进行预处理,使硫化物从混合烃体系中分离出来,再通过仪器和相应标样进行类型分析或结构鉴定。目前研究者在此方面做了很多工作,花瑞香等用29种硫化物标样,采取GC／SCD辅以选择性化学反应对汽油馏分的硫化物形态分布研究。     

不同孔隙率及孔径泡沫铝的力学与吸能特性研究

对三种孔径两种孔隙率共六种泡沫铝试件进行了静态压缩试验,发现对于中孔隙率材料,孔隙率对材料力学性能和吸能性能仍有明显影响:孔隙率越大,其吸能能力越强,但是屈服极限越小.孔径对材料吸能能力也有一定影响.同时,试验中还发现,对于孔隙率为55%的材料,当孔径≤1mm时,泡沫铝材料的孔径对其力学性能及吸能性能影响甚小.     

Spin-locking mechanism of spin I=3/2 quadrupolar nuclei undergo magic angle spinning

The spin-locking mechanism of the spin I=3/2 quadrupolar nuclei under magic angle spinning (MAS) has been theoretically and experimentally investigated, and the criterion of adiabatic passage around zero-crossings of the quadrupole splitting was inferred from the time-dependent Shrödinger equation in this article. The theory, numerical simulations, and experiments conducted in this work all indicated that second-order quadrupole interaction and off-resonance play important roles in the spin-locking of the quadrupolar nuclei, and they were responsible for the great loss of the spin-locking signals. The spin-locking for a spin I=3/2 nucleus might be achieved by minimizing the effect of the second-order quadrupole interaction by using a radio frequency (RF) offset. This offset was realized by setting the RF to the opposite position of the isotropic second-order quadrupolar shift of single quantum coherences.