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1.
本文研究了α,α'-二氧代烯酮环二氮代缩酮的特征红外光谱,指出了它们随化学结构而变化的规律。  相似文献   

2.
α,α′—二氧代烯酮环二硫代缩酮的特征红外光谱(II)   总被引:2,自引:2,他引:0  
本文在前文的基础上继续研究了α,α′-二氧代烯酮环二硫代缩酮的其他一些特征红外光谱,指出了它们随化学结构而变化的规律。  相似文献   

3.
本文研究了α,α′-二氧代烯酮环二氮代缩酮的特征红外光谱,指出了它们随化学结构而变化的规律。  相似文献   

4.
本文研究了α,α'-二氧代烯酮环二硫代缩酮的酮基与碳碳双键的特征红外光谱,指出了它们随化学结构而变化的规律。  相似文献   

5.
本文在前文[1]的基础上继续研究了α,α′-二氧代烯酮环二硫代缩酮的其他一些特征红外光谱,指出了它们随化学结构而变化的规律。  相似文献   

6.
本文研究了α,α′-二氧代烯酮环二硫(氮)代缩酮的紫外光谱,指出了它们随化学结构而变化的一些特征。  相似文献   

7.
在两种不同溶剂条件下,研究了5种α,α′-二氧代烯酮环二硫代缩酮类化合物的紫外光谱特性.在同一种溶剂条件下,比较含氮化合物与含硫化合物的紫外光谱特性,指出了它们随化学结构不同而变化的规律.  相似文献   

8.
在两种不同溶剂条件下,研究了5种α,α′-二氧代烯酮环二硫代缩酮类化合物的紫光光谱特性。在同一种溶剂条件下,比较含氮化合物与含硫化合物的紫外光谱特性,指出了它们随化学结构不同而变化的规律。  相似文献   

9.
研究了5种α,α′-二氧代烯酮环二硫代缩酮类化合物的羰基、碳碳双键、碳硫等一些特征红外光谱,尤其着重研究了在共轭体系下的各种特征谱带随化学结构而变化的规律.  相似文献   

10.
研究了5种含有苯环取代基的α,α′—二氧代烯酮环二硫代缩酮类化合物的红外光谱的特征吸收规律,指出了这类化合物分子结构对红外吸收谱带的影响;对^1H NMR,^13C NMR共振谱带做了全面的归属。并且讨论了分子结构对^1H NMR,^13C NMR共振谱带化学位移的影响,其变化规律与红外光谱一致,为这类化合物的结构及谱学研究提供了启发性的模式。  相似文献   

11.
Comprehensive theoretical investigations of the electronic structure of isoelectronic Ge, GaAs, ZnSe, and CuBr crystals have been carried out. The band structure has been calculated by the LAPW method. The total and partial densities of states have been determined and the permittivity spectra have been calculated by the tetrahedron method. The nature of maxima of the ?2 band spectra and their dependence on the chemical bond type have been determined.  相似文献   

12.
It is shown that operations of equivalence cannot serve for building algebras which would induce orthomodular lattices as the operations of implication can. Several properties of equivalence operations have been investigated. Distributivity of equivalence terms and several other 3-variable expressions involving equivalence terms have been proved to hold in any orthomodular lattice. Symmetric differences have been shown to reduce to complements of equivalence terms. Some congruence relations related to equivalence operations and symmetric differences have been considered.  相似文献   

13.
Rotational spectra of three isotopic species of carbonyl chlorofluoride, OCCIF, have been extensively measured, and have been analyzed for rotational constants, quartic centrifugal distortion constants, and chlorine nuclear quadrupole coupling constants. Ab initio calculations of the harmonic force field have been made using several different sets of basis functions, and their relative cost efficiency has been assessed. The measured distortion constants have been combined with vibrational wavenumbers (both from the literature and from the present work) and with the ab initio force constants to refine the force field. Ground state effective (r0) and average (rz) structures have been evaluated for the molecule.  相似文献   

14.
Thirty-nine unattributed electronic states of group IV monohalides have been interpreted in terms of Rydberg configurations. Ionization potential and quantum defects have been derived.  相似文献   

15.
S N Chatterjee  B N Roy 《Pramana》1986,27(6):795-802
Alpha particle and deuteron impactL-subshell ionization cross-sections of Ar, Cu, Ge, Br, Zr and Ag have been computed using Vriens’ expressions for ionization cross-section of atoms due to impact of heavy charged particles. The effects of Coulomb deflection of the projectile and increase in binding of the target electron in the presence of projectile have been incorporated. Hartree-Fock velocity distributions for the target electrons have been used in the present calculations. The simple binary encounter approximation model is found to give results which are in satisfactory agreement with those obtained from experiments and from other theories.  相似文献   

16.
The ground state dissociation energies of CN, PbF, SiF, SnF, SnS and NBr molecules have been estimated using the empirical electronegativity potential function proposed by Szöke and Baitz. The dissociation energies for these molecules have been found to be 7.9, 3.2, 4.2, 3.2, 3.0 and 2,7 eV respectively and compared with the earlier values.  相似文献   

17.
New measurements of the ozone spectrum in the microwave and 10-μm infrared regions have been made. These new lines have been fit to a three-state Hamiltonian model which includes Coriolis interactions beteen (0, 0, 1) and (1, 0, 0). The model requires additional Coriolis parameters, as well as an appreciation for the parameters which are indeterminate. Transition dipole moments have been derived from the intensities of selected infrared lines.  相似文献   

18.
Extreme events that change global society have been characterized as black swans. The frequency-size distributions of many natural phenomena are often well approximated by power-law (fractal) distributions. An important question is whether the probability of extreme events can be estimated by extrapolating the power-law distributions. Events that exceed these extrapolations have been characterized as dragon-kings. In this paper we consider extreme events for earthquakes, volcanic eruptions, wildfires, landslides and floods. We also consider the extreme event behavior of three models that exhibit self-organized criticality (SOC): the slider-block, forest-fire, and sand-pile models. Since extrapolations using power-laws are widely used in probabilistic hazard assessment, the occurrence of dragon-king events have important practical implications.  相似文献   

19.
Formulas for the surface tension coefficient, adhesion energy, elastic modulus, and strength of solids versus the atomic density have been derived. The theoretical values of these parameters have been confirmed by experimental data gathered from many metals, insulators, and semiconductors.  相似文献   

20.
Laser surface cleaning, de-rusting, de-painting and de-oxidizing   总被引:1,自引:0,他引:1  
Many materials have been tested as substrates and surface products. Typically ferrous (Carbon Steels and Stainless Steels) and non-ferrous (Al and Cu metals and its alloys) materials have been employed. Some epoxy, polyurethane, polyester and acrylic paints with different thickness and colour have been tested. Many types of surface rust and oxide on different bulk material have been undertaken to test. Similarly, some different types of oils and greases commonly used in industry to prevent oxidation, have been studied. Different types of laser sources have been employed: an axial fast flow, 1.5 kW CO2 c.w. and pulsed laser source emitting a 10.6 7m beam; and a portable Nd:YAG laser, Q-switchedand normal-mode source: 1st harmonic 1.064 7m (6 ns pulse duration), 2nd harmonic 532 nm (120 7s duration pulse, 1 J max per pulse) wavelengths, multi-articulated seven mirror beam guiding device, 20 Hz repetition rate. This provides shots with 600 mJ maximum energy per pulse and 100 MW peak power per pulse with very low beam divergence: 0.5 mrad at full angle.  相似文献   

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