AN ELECTRON MICROSCOPE STUDY OF MINERAL GROUP OF FRANCKEITE

Franckeite and cylindrite of franckite mineral group were examined in the transmission electron microscope. Selected-area electron diffraction indicated that in the structure exists a long period, belonging to an incommensurate modulation period. The incommensurate modulation in this kind of minerals results from sine undular structure sheets. The excellent correspondence between high resolution simulated computer image and observed image was obtained on the basis of the structure of franckeite and cylindrite which was put forward in this paper. First, the fact that in the structures of franckeite and cylindrite exist two kinds of structure sheets whose lattices are different has been proved by experiment, i. e. false tetragonal symmetrical galena structure sheets(t sheets)and false hexagonal SnS_2 sheets(h sheets). The two kinds of sheets are packed in order of htht…     

SIGNIFICANCE OF AUTHIGENIC MICROSPHEROID PYRITE BY SCANNING ELECTRON MICROSCOPE

This article discusses in detail the authigenic microspheroid pyrites in sediments by the scanning electron microscope, especially their basic types, surface structure and the surface changes of the single crystals in the kerogen of source rocks as well as their relation to the types of kerogen.     

ELECTRON MICROSCOPIC AUTORADIOGRAPHIC STUDIES ON DYNAMICS AND LOCATION OF DNA SYNTHESIS OF DUCK PLAGUE VIRUS

Electron microscopic autoradiographic studies on the dynamics and location of DNAsynthesis by means of incorporation of ~8H-thymidine during the replication of duck plaguevirus (DPV) revealed that the duration of DNA synthesis of DPV was rather long. The repli-cation of viral DNA occurred simultaneously with the assembly procedure of nucleocapsids, thematuration and release of viruses. DNA synthesis of DPV occurred in the matrix with lowerelectron density in the nucleus. The replicated viral DNA accumulated in the viroplast With highelectron density where the assembly of nucleocapsids occurred. The viroplast with high electrondensity was not the region of viral DNA synthesis.     

COMPARATIVE OBSERVATION OF FIRST MITOSIS IN DIFFERENTIATION AND

On the basis of observing the continuous process of the first mitosis of normal differ-entiation in vivo and comparing this observed results with the process of the first mitosisof dedifferentiation in vitro in wheat pollen grains, the cytological differences between thetwo kinds of mitosis have been found. These differences are expressed chiefly by the posi-tions of nuclei and cytoplasm as well as the positions and shapes of spindles and new cellwalls. The author considers: (i) The differences exist as soon as cell division begins. Sothe critical moment causing cell dedifferentiation is at the interphase instead of the divisionstage. Therefore, the viewpoint that the cause of dedifferentiating initiation is the altera-tion of the direction of the spindle axis could not be agreed. (ii) The cause producing thesecytological differences can be related to the loss of polarity in the dedifferentiating process.     

NUCLEAR TRANSPLANTATION IN TELEOSTS——HYBRID FISH FROM THE NUCLEUS OF CRUCIAN AND THE CYTOPLASM OF CARP

Hybrid fish are obtained from the combination of nucleus and cytoplasm from two generaof fresh-water teleosts using the technique of nuelear transplantation (i.e. the combination ofthe nucleus of erueian (Carassius auratus) and the cytoplasm of carp (Cyprinus carpio)). Morphological characteristics of these hybrid fish that have been examined so far indicatethat some features such as barbs, pharyngeal teeth, the number of scales along the lateral line,and the number of vertebrae are similar to those of crucian. Some of the hybrid fish growto normal adult fish.     

NUMERICAL SIMULATION OF MORPHOLOGY OF POLYMER CHAIN COILS IN COMPLEX FLOWS

A new coupled finite element formulation is proposed to calculate a conformation tensor model in two complex flows： a planar contraction flow and a planar flow around a symmetrically placed cylinder. The components of conformation tensor are first computed together with the velocity and pressure to describe the change of morphology of polymer chain coils in flow fields. Macroscopic quantities of viscoelastic flow are then calculated based on the conformation tensor. Comparisons between the numerical simulations and experiments for stress patterns and velocity profiles are carried out to prove the validity of the method.     

ELECTROCHEMICAL BEHAVIOR OF FERROIN IN IMPROVED PEO-LICLO_4 COMPLEX

Solid-state cyclic voltammetry was used to study electrochemical behavior of ferroin,which indicates that ferroin performs a reversible redox process in the improved PEO-LiClO_4complex.An activation energy of ca.6.0 Kcal/mol for ferroin diffusion was evaluated fromtemperature dependence of diffusion coefficient.     

THE ROTATION BARRIER OF ELECTRON SPIN PROBE IN THE STUDY OF POLYMER SYSTEM

In the study of molecular motion of polymer by means of ESR in combination with spin probe, owing to that the ESR spectrum depicts only the behavior of spin probe, the information obtained is of indirect nature. Hence the relationship between them must first be investigated before any conclusion could be drawn. In this paper, two parameters T_R and C_R are introduced to characterize the changing of tumbling rate of spin probe, and the concept of rotation barrier of spin probe is proposed. It is considered that the magnitude of the rotation barrier is determined by the internal cavity size and distribution in polymer. When the temperature is raised, the size and distribution of the cavities change accordingly, thus the tumbling of spin probe changes gradually from a slower to a higher rate.     

STUDIES ON STRUCTURAL-OPTICAL MINERALOGY——EFFECTS OF ELECTRON

In this paper, the Gladstone-Dale ionic refractivities (GDIR values) are calculated onthe basis of the K values given by Mandarino and/or the author. The effects of the elec-tron shell configuration of ions on the refractive properties of minerals are discussed. Theconclusions are as follows: (1) The refractive indices of the compounds consisting of Ne-type ions are linearlyrelated with their densities. (2) The ionic refractivities of the inert gas-type ions are different from those of 18electron-type ions in their variation relationship. (3) The ionic refractivities of ⅠA, ⅡA, ⅢA, ⅣA, ⅤA and ⅥA Groups in the periodictable increase linearly with increasing atomic number. (4) The two-humped curves are found for the ionic refractivities of the first transitionelements. (5) Because of the lanthanum series contraction, the ionic refractivities of rare earthelements decrease with increasing atomic number.     

OBSERVATION OF ENERGY DISSIPATION PEAK IN POLYSTYRENE MELT ABOVE Tg

In this paper two different kinds of dynamic mechanical techniques(inversed torsion pendulum and energy dissipation apparatus)were used to study the dynamic behavior of atactic monodisperse polystyrene above glass transition. The plots of energy dissipation versus temperature were presented for two atactic polystyrene samples.An apparent energy dissipation peak occurred above T_g in each plot measured by the inversed torsion pendulum,and simultaneously the sample was found to flow assuredly at the moment.To exclude the influence of the flow and demonstrate there was a peak indeed above T_g,the energy dissipation apparatus was used,in which the samples were put into a cup.An obvious peak appeared, and it was in agreement with the peak observed by the inversed torsion pendulum.On basis of the results measured by the two kinds of apparatus,a conclusion is drawn that a peak occurrs above T_g,which gives a manifestation for the existence of the liquid-liquid transition.     

ABSORPTION SPECTRA OF 4f ELECTRON TRANSITIONS IN THE SYSTEM OF NEODYMIUMSEMIXYLENOL ORANGE-CETYLPYRIDINIUM CHLORIDE

In this paper the absorption spectra of Nd-SXO-CPC complex by 4f electron transitions have been studied by zero-order and fourth-order derivative spectrophotome-try. The molar absorptivity is 2.6×10~3 1.mol~(-1).cm~(-1) at 585 nm, the fourth-order derivative molar absorptivity is 1.4×10~4 1.mol~(-1).cm~(-1) at 584.5(-) and 587(+) nm. They are 300 times and 1600 times greater than those of the chloride, respectively.     

OXIDATION OF Tb(Ⅲ)IN THE HETEROPOLY-TUNGSTOPHOSPHATE COMPLEX

It has first been reported that Tb(Ⅲ)is oxidated by K_2S_2O_8 in the heteropoly-tungstophosphate complex.The complex ion,[Tb(Ⅳ)(PW_(11)O_(39))_2]~(10-),is stable in aqueous solutiononly for hours,being graduately reduced to[Tb(Ⅲ)(PW_(11)O_(39))_2]~(11-).It is red-brown,with absorptionband at about 420 nm.     

THE OBSERVATION OF INTERNAL MOTION OF LINEAR POLYSTYRENE CHAINS IN CYCLOHEXANE AROUND θ TEMPERATURE

 A high molecular weight (Mw = 1.85 × 10⁷) polystyrene (PS) with narrow distribution was prepared by high vacuum anionic polymerization in tetrahydrofuran. By use of dynamic light scattering, the dynamics of PS chains in cyclohexane was studied around the θ temperature. For the first time, we have observed the internal motion of polymer chains in solutions below the θ temperature by using dynamic light scattering at smaller angles (even qR_g < 1).     

THE OBSERVATION OF INTERNAL MOTION OF LINEAR POLYSTYRENE CHAINS IN CYCLOHEXANE AROUND 0 TEMPERATURE

A high molecular weight (M_w=1.85×10~7) polystyrene (PS) with narrow distribution was prepared by high vacuum anionic polymerization in tetrahydrofuran.By use of dynamic light scattering,the dynamics of PS chains in cyclohexane was studied around theθtemperature.For the first time,we have observed the internal motion of polymer chains in solutions below theθtemperature by using dynamic light scattering at smaller angles (even qR_g<1).     

PHOTO-ASSISTED ELECTRON TRANSFER IN A NICKEL(II) PORPHYRIN COMPLEX: FORMATION OF NICKEL(III)-PORPHYRIN π-CATION RADICAL

Abstract

In sunlight the complex Ni^II(TPP) {TPP=tetraphenylporphyrin} undergoes photolysis in CH₂Cl₂ to produce a stable nickel porphyrin π-cation radical [Ni^IITPP?]⁺ species which has been characterised by epr measurement.     

TRANSFORMING GENES IN DUCK HEPATIC CARCINOMA——mht(raf) AND Ha-ras

The transfection of NIH 3T3 cells was performed with DNAs from 2 duck primary hepatic carcinomas (DHC 40K, 9K) and I tumor-adjacent liver tissue (TAL, 9N). Transfectants were found from 40K, 9K and 9N DNAs. The secondary transfectants were obtained after transfection of RAT-1 cells with DNAs from primary transfectants. After hybridization with Ha-ras, Ki-ras, N-ras and mht oncogenes, it was found that duck mht (5.2 and 3.2 kb EcoRI fragments) and duck Ha-ras (3.4 kb EcoRI fragments) were present in all these transformants.This is the first report on transforming genes in duck primary hepatic cancer as well as tumoradjacent liver tissue     

ION CONDUCTION IN COMPLEX OF ACRYLONITRILE-COPOLYMERIZED COMB POLYETHER WITH LITHIUM PERCHLORATE

Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of polymer structure. At proper copolymer composition, lithium concentration and pendant length, the ion conductivity reaches 7.0×10~(-5)S/cm at ambient temperature, together with improved mechanical strength. The ion transport in the polymer media is assisted by segmental relaxation, which is confirmed both by the consistency between ion conductivity and T_g and by the study of TSC.     

PROTON NUCLEAR MAGNETIC RESONANCE AND ELECTRON PARAMAGNETIC RESONANCE INVESTIGATION OF α-α CROSS-LINKED Fe-Co HYBRID HEMOGLOBINS

The following asymmetric α1 99 Lys-α2 99 Lys cross-linked Fe(Ⅱ)-Co(Ⅱ) hybrid hemoglobins (Hbs) were first prepared from derivatives of hemoglobin C (β6 Glu-Lys) and human normal HbA: [α(Co)β(Fe)]A[α(Co)β(Co)]cXL, [α(Fe)β(Co)]A[α(Co)β(Co)]cXL, etc.Their 500 MHz 1H NMR and EPR spectra were measured in order to study the change in their tertiary and quaternary structure under atmosphere of deozy, oxy and carbon monoxide (with or without IHP). From the change of T and R marks in 1H NMR hydrogen bonding region, it is proved that oxygen molecules are first bonded to α(Fe) subunits rather than to β(Fe). The experimental phenomena provided further evidence that intermediate states of ligation are present in addition to T and R state during process of binding of oxygen to Hb. IHP facilitates transformation of T state to R state. The same conclusion can also be drawn from the results of EPR spectra at 77 K.     

THE FORMATION OF ALTERNATING TRIADS AND THE FORMATION OF CIS LINKAGE CONFIGURATION BY A PARTICIPATION OF THE ELECTRON DONOR-ACCEPTOR COMPLEX OF THE MONOMERS IN THE COPOLYMERIZATION OF N-PHENYLMALEIMIDE AND 2-CHLOROETHYL VINYL ETHER†

The ¹³C NMR technique of distortionless enhancement by polarization transfer and quaternary ¹³C NMR are used to quantitatively determine the proportion of alternating triad and the proportion of cis/trans linkage configurations at the cyclic N-phenylmaleimide (PMI) monomer units in the copolymers of PMI and 2-chloroethyl vinyl ether (CEVE), which are prepared by a radical initiator in chloroform solvent at 50°C.

The amount of the cis linkage configuration at PMI units is found to be proportional to the amount of alternating CEVE-PMI-CEVE triads in the copolymers; i.e., a relation, (% of cis linkages at PMI units) = (48 ± 5.0%) (mol fraction of CEVE-PMI-CEVE triads), is found in the PMI-CEVE copolymers. It is concluded that the cis linkage configuration is formed predominantly in the process of the formation of the alternating CEVE-PMI-CEVE triads in this copolymerization, and that, according to the Olson-Butler mechanism of a complex participation, 48 ± 5.0% of all the reactions which give CEVE-PMI-CEVE triads is the attack by growing CEVE radicals on the PMI component of an electron donor-acceptor (EDA) complex of the comonomers from the syn direction relative to the CEVE component of the complex. The equilibrium constant K of the 1:1 EDA complexation in chloroform at 25°C is determined to be 0.260 L mol^?1 by ¹H NMR spectroscopy.     

THE CALCULATION OF NUCLEAR SPIN-SPIN COUPLING CONSTANTS IX THE CALCULATION OF COUPLING CONSTANTS IN DISUBSTITUTED PYRIDINES

<正> The principle and Method for calculating the coupling constants of substituted benzenes have been extended to the calculation of coupling constants in disubstituted pyridines. The parameters 13 of some substi-tuents have been provided. The calculated results of 241 J values from 95 compounds show that the standard deviations between the calculated and the experimental values are within 0.11 Hz.