Far-infrared spectrum of excited torsional states of C-13 methanol

The torsion-rotation structure of the far-infrared (FIR) spectrum of the C-13 isotopic species of methyl alcohol has been investigated by high-resolution Fourier transform spectroscopy in the 25–350 cm^–1 region, with emphasis on subbands involving excited torsional states. In this study, 89 such subbands have been identified, with torsional states fromn=1 ton=3 included. As well, a further 4 assignments have been added to our previous work on then=0 ground torsional state. The subband origins together with known microwave results have been fitted by least-squares to our torsion-rotation Hamiltonian, and improved molecular structural and torsional constants for the vibrational ground state are reported. Tables of state-specific constants representing the three leading terms in aJ(J+1) power-series expansion of the torsion-rotation energy levels are given for torsional statesn=0 to 3 and rotationalK values from 0 to 16.     

Multivariate aging properties of epoch times of nonhomogeneous processes

The purpose of this paper is to give conditions on the parameters of nonhomogeneous Poisson and nonhomogeneous pure birth processes, under which the corresponding random vector of the first n epoch times has some multivariate stochastic properties. These results provide an inside to understand the effect of the time over the occurrence of events in such processes. Some applications of these results are given.     

Asymmetric synthesis of α-monofluoromethyl- and α-difluoromethylbenzylamines through regioselective hydrogenolysis

Asymmetric synthesis of α-monofluoromethyl- and α-difluoromethylbenzylamines through regioselective hydrogenolysis is described. Hydrogenolysis of diastereomerically pure bis(α-methylbenzyl)amine derivatives having partially fluorinated methyl group at benzylic position also proceeded with a high regioselectivity as well as in the case of α-trifluoromethyl group. Moreover, opposite asymmetric induction was observed in reduction of chiral imines derived from partially fluorinated acetophenone and α-phenylethylamine.     

Torsional refilling transitions in tea-pumped CH3OH fir lasers with associated high-resolution fir spectra

It is proposed that a number of the high-frequency far-infrared (FIR) laser lines observed when CH₃OH is optically pumped by high-power CO₂ TEA lasers can be identified as refilling torsional transitions within the vibrational ground state. Assignments are presented for 8 such TEA-pump/FIR-laser refilling systems. To provide support for the assigned laser frequencies, high-resolution Fourier transform FIR spectra of CH₃OH have been obtained and partially analyzed in the torsional transition region.     

用非笛卡儿张量分析螺旋状矩形管的流动特性

利用基于带有物理基的非笛卡儿张量分析的广义矩阵法，在非正交的螺旋线坐标系中。推导出了连续性方程和Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程组．并利用有限元法．解出了上述偏微分方程组．借以分析研究了螺旋状矩形管在定带、充分发展的层流流动中，管的曲率、挠率和横截面倾斜角对流动特性的种种影响，并适当地与环状矩形管作了比较，从中探索出流动参数的变化对流动特性变化影响的规律。     

A new series of materials containing basic sulphates of iron(III)

Series of basic sulphates which were precipitated by the hydrolysis of Fe(OH)SO₄ in the presence and absence of metallic iron were studied from compositional, crystallographic and thermal decomposition points of view. The results are presented and discussed. It was found that high pure iron oxides as well as high grade red iron oxide pigments can be obtained by agitating the basic sulphates in hot ammonical medium followed by roasting. Commercial exploitation of the results is suggested.Left the laboratory to settle in domestic life.The authors are thankful to the Director, Prof. H. S. Ray for his kind permission to publish the results. One of us (SM) is also thankful to the Council of Scientific and Industrial Research, New Delhi, for the award of a Senior Fellowship.     

Determination of Newtonian gravitational constantG with swing time method

The Newtonian gravitational constantG is determined by means of the swing time method at the Cave Laboratory of Center for Gravitational Experiment of Huazhong University of Science and Technology. The result value ofG is (6.669 0 ± 0.001 6) × 10^-11 m³·kg^-1·s^-2, which is consistent with the CODATA value of G obtained by Cohen and Taylor in 3σ. Project supported by the National Natural Science Foundation of China (Grant Nos. 19425008 and 49674246).     

带裂纹圆柱体扭转的强奇性积分方程解法

本以裂纹的翘曲位移间断为基本未知函数，把带裂纹圆柱体的扭转问题化为求解一组强奇性积分方程，并利用数值法，对星形及其不同形状裂纹圆柱体的抗扭刚度和应力强度因子作了数值计算，计算结果令人满意。     

Wigner Function:from Ensemble Average of Density Operator to Its One Matrix Element in Entangled Pure States

We show that the Wigner function W = Tr(△ρ) (an ensemble average of the density operator ρ, △ is theWigner operator) can be expressed as a matrix element of ρ in the entangled pure states. In doing so, converting fromquantum master equations to time-evolution equation of the Wigner functions seems direct and concise. The entangledstates are defined in the enlarged Fock space with a fictitious freedom.