论二阶电路的谐振频率

本文在二阶电路传输函数的基础上讨论了它的固有频率与输出响应峰值频率的关系和固有频率与输入电流电压同相频率关系,发现二阶电路的谐振频率不是零输入电抗的频率,而是它的固有频率．但在调谐实践中以输出响应的峰值频率作为谐振指示是合适的．     

The frequency-domain method reveals the dimeric structure of Na,K-ATPase

Lucifer yellow and lissamine rhodamine sulfonyl hydrazine were used as the donor and the receptor, respectively, for Förster energy transfer measurements to determine the location of the subunit in the native Na,K-ATPase from pig kidney. It was found that (1) the subunits are located in one functional complex, i.e., the dimer ()₂ appears to be the functional complex of Na,K-ATPase, and (2) the subunits in the functional enzyme complex in the membrane are not located next to each other but are rather well separated. The distance between fluorophores covalently attached to the subunits was found to be 5.3 nm.     

EFFECTS OF SOURCE PROPERTIES ON CUTOFF FREQUENCY f_(max)

The cutoff frequency f_(max) of radiation from earthquakes is one of the important parameters for studying the source process. By theoretical analysis and numerical experiments on acceleration Fourier spectrum it is suggested that f_(max) mainly depends on the lower values of slip rise time. This result can be used to explain the observational fact that the greater the earthquake magnitude, the smaller the value of f_(max).     

New far infrared laser lines obtained by optically pumping13CD3OD

We have obtained laser action on 34 far infrared lines for the first time in fully deuterated methyl alcohol with the¹³C isotope (¹³CD₃OD), and we have measured the frequency of 13 lines. The molecule was pumped by a cw CO₂ laser. We have measured the wavelength, the relative polarization, the relative intensity of most lines, the frequency, and the CO₂ pump frequency offset of the strongest lines. The new lines are distributed in the wavelength region from 75.27 m to 464.7 m.Supported in part by a joint grant with the U.S. National Science Foundation grant # INT 80-19014 and the Brazilian Conselho Nacional de Pesquisas (CNPq).     

用ab initio方法研究NaN_3的几何构型、电子结构和热力学、动力学性质

用ａｂｉｎｉｔｉｏＭＯ方法，在ＭＰ２（ｆｕｌ）／６３１１Ｇ水平下，全优化计算了叠氮化钠（ＮａＮ３）分子的线状和环状两种稳定构型及其转化过渡态的几何参数、电荷分布、分子总能量和振动频率，并研究了它们的热力学性质及转化速率常数和平衡常数．结果表明，线状比环状构型稍稳定（能量低６．０４ｋＪ／ｍｏｌ）；两者相互转化的能垒分别为１３．１５ｋＪ／ｍｏｌ（线型→环状）和７．１１ｋＪ／ｍｏｌ（环状→线型）．热力学和动力学计算均表明：ＮａＮ３通常主要以线型结构存在（占８５％以上），且随温度升高而增多（在１０００Ｋ大于９１％）．     

原子氧在Ru低指数面及(110),(111)台阶面上的吸附

利用原子与表面簇合物相互作用的5参数Morse势方法(简称5-MP)系统地研究了O-Ru低指数面及Ru(1120),(1121)台阶面体系,获得了吸附几何、结合能、振动频率等临界点特性,所得相关数据与实验结果非常吻合.并且通过理论计算及原子吸附态振动指纹的遗传、遗变特性预言了氧原子在Ru(1121)台阶面的吸附.本文认为氧原子在HCP晶格的金属表面上的吸附倾向于三重位.     

烷基极化效应与X=O键伸缩振动频率

烷基取代物R’X=0的X=0键伸缩振动频率ν与烷基R的极化效应指数PEI(R)的关系可表示为:ν=a bPEI(R)。研究结果表明,烷基的极化效应使X=0键的伸缩振动频率降低。     

Electron capture detector performance parameters in view of the response presentation forms

Summary Four most frequently used presentation forms of the ECD response are described. Equations describing the dependence of the sensitivity, linearity and minimum detectable concentration of the ECD working under constant frequency mode of operation on the pulse period are derived from Wenthworth’s kinetic model for all four forms mentioned above. The forms presented are compared on the basis of equations derived. Results of the calculations are given and some predictions are experimentally tested for sulphur hexafluoride. Good agreement was found between the predicted and observed relationships. Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984     

电解沉积压电频移分析的理论与验证

提出了控制电位电解和恒电流电解两类电解沉积的压电频移分析法测定的理论公式,用实验结果验证了它的正确性.     

Theoretical study on the molecule C30H20: five carbon–carbon single bonds linking a dodecahedrane cage and a pentaprismane cage

Using geometry optimization and DFT method at the B3LYP/6-31G* level of theory for C₃₀H₂₀, an equilibrium geometry is identified that has the form of polyhedral hydrocarbon with five carbon–carbon single bonds linking a dodecahedrane cage and a pentaprismane cage. Thus, this molecule is a tri-cage molecule with two pentaprismane cages and one dodecahedrane cage. Vibrational frequencies and the infrared spectrum are computed at the same level of theory. The heat of formation for C₃₀H₂₀ has been estimated in this paper. The heat of formation of C₃₀H₂₀ as well as the vibrational analysis indicates that this molecule enjoys sufficient stability to allow for its experimental preparation.