Layered K2Ti4O9 thin films were prepared from the suspension of fine particles K2TiO9 by spin coating. The suspension was obtained by wet grinding and centrifugalizing of the K2Ti4O9 powder, which was got by sintering the analytical pure TiO2 and K2CO3. Also, the structure of the thin films was Characterized by XRD and SEM.

To obtain CdS/K4Nb6O17 thin film through the same course of making CdS/K4Nb6O17 powder on the base ofK4Nb3O17 thin film on the quartz which made by the spin coating and after heat treatment.

drying white tungsten concentrate by spin Flash Dryer theory and method were introduced by which the traditional drying method and product quality can be improved and the frugal energy and production cost were reduced,the working conditions were improved.

(C4H9NH3)2MCl4(M=Mn, Zn) and (C4H9NH3)2PbX4(X=Br, I) films were prepared on glass and quartz substrate separately using spin coating technique and were characterized by XRD, the results told us the corresponding layered perovskite-type films formed;

If is a ?2-grading of a simple Lie algebra, we explicitly describe a-module Spin0 () such that the exterior algebra of is the tensor square of this module times some power of 2.

Although Spin0 () is usually reducible, we show that a Casimir element for always acts scalarly on it.

The nonselective, selective and double-selective spin-lattice relaxation rates of some protons in huperzine E were acquired in the absence and presence of AchE at a concentration ratio of [ligand]/[protein] = 1: 0.005.

Direct current magnetic susceptibility measurement in the 2-300 K temperature range supports a high-spin ground state.

In particular, the analytical forms of the one-body and two-body FPC for the total spin states with {N} and {N-1,1} permutation symmetries have been derived.

A new approximation method is proposed in this article for the discussion of molecular structures,and this new method includes the two well-known theories,molecular orbital theory and electron-pair bond theory as two special cases.Let a molecule have n bonds and let the ith bond be described by the anti-symmetrical two-electron bond function ψ_i(v_(2i-1),v_(2i)).(If there exist one- electron,three-electron or many-electron bonds,they can be similarly described by the corresponding one-electron,three-electron...

A new approximation method is proposed in this article for the discussion of molecular structures,and this new method includes the two well-known theories,molecular orbital theory and electron-pair bond theory as two special cases.Let a molecule have n bonds and let the ith bond be described by the anti-symmetrical two-electron bond function ψ_i(v_(2i-1),v_(2i)).(If there exist one- electron,three-electron or many-electron bonds,they can be similarly described by the corresponding one-electron,three-electron or many-electron bond func- tions.) Then the stationary state of the molecule is represented by the follow- ing wave function Ψ, where the summation is over all permutations of 1,2,……,2n except those within the interior of the functions,since each ψ_i is already anti-symmetrical.Obviously (2~n/((2n)/!))~(1/2) is the normalization factor. By quantum mechanics the energy of the molecule equals (1) here H_i,T_(ij) and S_(11)' are respectively the following three kinds of operators, (2) (3) (4) The third term of equation (1) is the exchange integral of electrons 1 and 1', while (1,2') is that of electrons 1 and 2'.According to the definition of bond functions,ψ_i may be written as (5) Substituting equation (5) into equation (1) and carrying out the integration over spin coordinates,we obtain (6) It can be easily seen from equation (6) that the combining energy of a mole- cule consists of two parts,one being the binding energy of the bonds represent- ed by the first term of equation (6),and the other being the interaction energy of the bonds denoted by the second term of that equation. If we choose certain functions φ_i~('s) involving several parameters and substi- tute them into equation (6),we may determine the values of those parameters by means of the variation principle. For the discussion of bond interaction energies,we develop a new method for the evaluation of certain types of three-center and four-center integrals.The interaction energy of a unit positive charge and an electron cloud of cylindrical- symmetry distribution may be written as (7) where (8) and R_0~2=a~2+b~2+c~2 The interaction energy of two electron clouds both of cylindrical-symmetry distributions with respect to their own respective axes is evaluated to be (9) (10) where is to sum over j from zero to the lesser value of n-2i and m, is to sum over i from zero to the integral one of n/2 and (n-1)/2,and is to sum over all cases satisfying the relation =m-j,while b_(n,n-2i) represents the coefficient of x~(n-2i) in the n th Legendre polynomial.

The main difficulty of the one-electron theory of optical activity lies in the calculation of the so-called vicinal actions. This may be overcome, as suggested in the present investiga- tion by assuming that the vicinal actions are due to the interactions of various chemical bonds in the molecule with the chromophoric electron. For the calculation of these interactions the charge distribution of a single covalent bond is assumed to consist of two nuclei, each of unit positive charge, separated by the bond distance...

The main difficulty of the one-electron theory of optical activity lies in the calculation of the so-called vicinal actions. This may be overcome, as suggested in the present investiga- tion by assuming that the vicinal actions are due to the interactions of various chemical bonds in the molecule with the chromophoric electron. For the calculation of these interactions the charge distribution of a single covalent bond is assumed to consist of two nuclei, each of unit positive charge, separated by the bond distance and two electrons with opposite spins and a spherically symmetrical orbital eigenfunction represented by (?) where r is the distance measured from a certain point on the bond axis and near the center of the bond. The location of this point is so determined that the model will give the proper dipole moment of the bond. The exponent α, which determines the extent of diffusivity of the electron cloud, is obtained by an approximate variational treatment. The quadruple moment of this model, calculated for the C-H bond, agrees very well with that estimated by Lassettre and Dean from a study of the potential barrier hindering the internal rotation of the ethane molecule. To test the theory and also to illustrate the procedure which is followed in calculating optical rotations using the new model of vicinal actions, the optical rotations of several methyl derivatives of cyclopentanone have been calculated and the following conclusions have been reached: (1) The proposed model gives rise to optical rotations in agreement with the observed values. (2) The effect of the internal rotation of the methyl group on the molecular rotation [M]_D of 3-methylcyclopentanone is large, [M]_D being +44° and -130° for the cis- trans-conformations, respectively. (3) The observed [M]_D may be regarded as composed of two parts, namely, the contribution from the multipole terms and that from the orbital overlapping. The latter corresponds to the "incomplete screening of atomic nuclei", and has been regarded as the most important vicinal action in earlier calculations. In the present work, it is shown, however, that this effect contributes only a few percent of the total [M]_D, unless the perturbing group is very near to the chromophoric group as it is in the case of 2-methyl- cyclopentanone. The failure of the previous calculations is, therefore, due mainly to the omission of the multipole (especially the quadrupole) terms. (4) The absolute configuration of 3-methylcyclopentanone, indicated by the present calculation, is the opposite of the one suggested by Eyring, since he based on the overlapping contribution alone, which bears a sign opposite to that of the total [M]_D (5) That the observed [M]_D of 2,4,5,5-tetramethylcyclopentanone is considerably smaller than that of 2,4-dimethylcyclopentanone may be due to one or both of the following possibilities: (a) that the conformation of the 2- and 4-methyl groups slightly deviates from the trans-position in the tetra-methyl compound, due to the presence of the two additional methyl groups; (b) that the two additional methyl groups in 5,5-positions are not exactly symmetrical with respect to the ring so that they make contributions to [M]_D.

In this paper a 4-roller two-zone apron type super-high drafting apparatus is introduced. Considerations under which this apparatus was designed, like drafting capacity, method of controlling fibre motion, type of mechanism, etc., are described in detail. The emphasis is laid on the distribution of zone of frictional force before and after the roving entering each drafting zone. The importance of collectors in super-high drafting apparatus is thereby examined from this point of view, and the factors of their...

In this paper a 4-roller two-zone apron type super-high drafting apparatus is introduced. Considerations under which this apparatus was designed, like drafting capacity, method of controlling fibre motion, type of mechanism, etc., are described in detail. The emphasis is laid on the distribution of zone of frictional force before and after the roving entering each drafting zone. The importance of collectors in super-high drafting apparatus is thereby examined from this point of view, and the factors of their design exploited。 The results of its preliminary tests are described. It can be seen that the spinning test for 23~S english counts gives optimistic results though further tests are still required. Factors influencing the design and spinning conditions in this drafting apparatus are discussed at the end of this paper.