Showing papers by "Nanjing University published in 1981"
TL;DR: The discovery of previously unknown microfossils from the Sinian of western Hubei Province, South China (Fig. 1) is reported in this paper, where the micro-dolomites are preserved in siliceous nodules, particularly in the cherty portions.
Abstract: The discovery of previously unknown microfossils from the Sinian of western Hubei Province, South China (Fig. 1) is reported here. The Sinian there, up to 1,000 m thick, is naturally divisible into four formations (Fig. 2) from the base upwards: (1) the Liantuo Formation comprising feldspar–quartz–sandstones with basal conglomerates; (2) the Nantuo Formation, which is a tillite; (3) the Doushantuo Formation, which has micro-dolomites intercalated with black shales and cherty beds with some siliceous or phosphatic nodules; and (4) the Dengying Formation, which is mainly dolomites. The rock sample in which the microfossils were found was collected from the lower part of the Doushantuo Formation near the highway side ∼500 m east of Liantuo, Yichang County (Fig. 1). The Doushantuo Formation has been dated as 693±66 Myr (Rb–Sr isochron age)1. Pseudomorphs after gypsum sometimes occur in the lower part. The microfossils are preserved in siliceous nodules, particularly in the cherty portions. The dark colour of the nodules is due to the high organic content.
25 citations
12 citations
TL;DR: In this article, a remarkable influence of Ru3+ ions on the anisotropy of single crystals of PbFe12O19 was found, and the variation of K1 and Ha with T in a range of 100-273°K was investigated.
Abstract: A remarkable influence of Ru3+ ions on the anisotropy of single crystals of PbFe12O19 was found. Single crystals of PbFe12−xRuxO19 were grown by flux method. For small addition of Ru ions, the uniaxial anisotropy constant K1 increases sharply, and reaches a maximum at x = 0.05. Then, the K1 tends to decrease with further increasing x. A maximum relative increment of 27% in K1 was obtained at 273°K. Also, the variation of K1 and Ha with T in a range of 100–273°K was investigated. For the crystals with x = 0.35, the phenomenon of spin reorientation was observed with the change of easy direction from c axis to basal plane at the temperature around 200°K. Below 200°K, K1 becomes negative. In addition, K2 increases monotonously with decreasing temperature.
8 citations
TL;DR: Using a semi-analytical method, the authors obtained a first-order solution of the equations of motion of near-Earth satellites under the combined perturbing effect due to Earth's figure and air drag.
6 citations
TL;DR: In this article, the stability of stars located at the upper part of the main sequence, for which the CN-O cycle is the main energy source, was investigated.
4 citations
TL;DR: In this paper, the authors re-examined the stability of stellar structure with respect to the PPI reaction in solar type stars, and showed that the star is stable if the relative mass abundence of Hydrogen to Helium is less than 8.9, a condition which is amply satisfied by the normal stars.
4 citations
3 citations
TL;DR: In this article, the spatial variation of order parameter in S-N-S structure and the dependence of supercurrent on the thickness of normal film d N was investigated, and the semi-infinite periodic structure was shown.
Abstract: Some theoretical results are reported, 1) Proximity effects of N-S interface. 2) The spatial variation of order parameter in S-N-S structure and the dependence of supercurrent on the thickness of normal film d N . 3) The semi-infinite periodic N-S structure.
3 citations
TL;DR: In this paper, the authors made a statistical analysis on the subpulse width, the mean pulse width and the rate of change of polarization angle in pulsars and obtained empirical relations showing how these radio emission characteristics are related to the magnetic inclination and discussed the physical implications of the relations.
2 citations
TL;DR: In this paper, the dynamical features of a solar surge during its fall are satisfactorily explained using the basic picture and formulae presented in this paper, taking into consideration that, during the descending phase a weaker magnetic field must be used and the effect of atmosphereic resistance must be allowed for near the end.
2 citations
TL;DR: In this article, the energy bands and atomic plane projected density of states have been calculated in the tight-binding approximation for a model of LUCS, and the tight binding approximation has been shown to be tight in the case of a model LUCS.
Abstract: The energy bands and atomic plane projected density of states have been calculated in the tight-binding approximation for a model LUCS.
01 Jan 1981
TL;DR: In this article, it was shown that pulsars with long pulse nulling are located on a line near and parallel to the radio cut-off in the 1gP-1gP diagram.
Abstract: Taking pulsars with long pulse nulling as forming a special group, we found that those with pronounced nulling are located on a line near and parallel to the radio cut-off in the 1gP — 1gP diagram. This in turn suggests a reason for the nulling. They are also shown to have smaller than average fields at the light cylinder and to have smaller than average rates of energy dissipation.
TL;DR: In this paper, the effect of scattering by plasma turbulence on the Compton process was investigated and an X-ray spectrum was obtained in agreement with the observed spectrum, which is difficult to explain by the usual Compton mechanism.
TL;DR: A magnetostatic delay line (MSDL) composed of a longitudinally magnetized YIG single crystal rod is constructed in this paper, where the multiple round trip echoes observed, especially at short delay times, are sucessfully suppressed by changing the sample shape.
TL;DR: In this article, the effect of interstitial solutes on the grain boundary peak was investigated in pure iron and carbon-rich iron, and the activation energy for grain boundary relaxation was found to be 49±3 kcal/mol.
Abstract: Some investigations of the effect of interstitial solute additions on the grain boundary peak were made in iron. At the higher temperature side of the iron grain boundary peak, a "carbon solute peak" appeared for iron containing 0.0002 wt% and 0.0005 wt% carbon. The activation energy for grain boundary relaxation in pure iron is 49±3 kcal/mol find that for the "carbon solute peak" is equal to 85±4 kcal/mol. The solvent peak disappeared as the amount of carbon increased up to 0.0027 wt%. Therefore, it seems easy to explain the results given by Miles and Leak that no solute peak appeared together with the solvent peak in iron containing carbon and there was an abrupt change on the curve of variation of activation energy for grain boundary damping of iron with carbon content. The mechanism of solute peak was discussed.
TL;DR: In this paper, the authors investigated the mechanism of the formation of neutrino Astronomical Objects (NAO) and the relation of this formation to that of the galaxies, ascertained their e, p, He 4 content, whose presence should produce a series of observable effects.
01 Jul 1981
TL;DR: In this paper, different samples of meteorites (unheated and artificially heated) have been observed and studied by means of TEM (transmission electron microscope), as a result, primary and secondary microinclusions of less than 1 μ have been found in the meteorites.
Abstract: Different samples of meteorites (unheated and artificially heated) have been observedand studied by means of TEM (transmission electron microscope). As a result, primary andsecondary microinclusions of less than 1 μ have been found in the meteorites. Af the sametime, in the meteorites of Jilin, Dongtai and Lishui and in their fused crusts, microtexturesreflecting the agglomeration, melting, rotation and condensation of metcorites and collisionamong heavenly bodies during falling have been observed. Observation of the meteoritesamples heated under different temperatures has been made so as to ascertain the melted tex-ture and temperature of the falling meteorites. It shows that at different temperatures themelt textures are obviously different. The Jilin meteorites are melted obviously at 900-1050℃.
TL;DR: In this paper, a system of particles subject to mutual inelastic collisions and moving in the gravitational field of an ellipsoidal central body is numerically stimulated on computer, and it is shown that, after rapidly becoming flattened, the system enters a quasi-equilibrium state in the form of a disk of finite thichness.
01 Jan 1981
TL;DR: Peking man's cave, Zhoukoudian, Beijing, is a worldwide known site where fossils ofPeking Man have been discovered as discussed by the authors, the cave is a vertical limestone cave, filled with cave de-posits, more than 40 m thick.
Abstract: Peking man's cave, Zhoukoudian, Beijing, is a worldwide known site where fossils ofPeking Man have been discovered. The cave is a vertical limestone cave, filled with cave de-posits, more than 40 m thick. According to printciples of development of limestone caves, com-parison between cave deposits and sediments outside the cave, data of absolute dating, formerrecords of excavation of Peking Man's cave and suggestions from colleagues, evolution ofPeking Man's cave may be divided into 5 stages: stage of deep burial, stage when an Eastentrance was opened, stage when Peking Man mainly dwelled in eastern part of the cave, stageof the collapse of cave roof of Pigeon's Chamber and westward migration of Peking Man'shabitat and stage when the cave was filled up and Peking Man left the cave.
TL;DR: The longitude and obliquity components of the principal nutation terms were derived from observations made in 1955-1977 of 43 star pairs common to the ILS Programmes VI and VII.
TL;DR: In this paper, three methods are proposed to lessen the complexity in the derivation and the resulting expressions of second-order analytical solutions of artificial satellite orbits while retaining the advantages of analytical solutions.
01 Jan 1981
TL;DR: In this article, the electrical behavior of the mobile hydrogen ions in the thermally grown SiO2 films was studied by using the C-V measurements, thermally stimulated ionic current, and the avalanche injection techniques.
Abstract: The electrical behavior of the mobile hydrogen ions in the thermally grown SiO2 films were studied by using the C-V measurements, the thermally stimulated ionic current, and the avalanche injection techniques. It has been found that the hydrogen ions introduced into the thermally grown SiO2 films by water vapour or ethanol contamination are high mobility species under low electric field at room temperature. These mobile hydrogen ions can cause the instabilities of MOS structures at room temperature-bias. It has also been found that the mobile hydrogen ions located in the SiO2 films near the SiO2-Si interface may act as electron trap centers. In addition, the instabilities and electron trap centers due to the mobile hydrogen ions may be reduced by a low-pressure RF plasma annealing.
TL;DR: In this paper, it was shown that pulsars with long pulse nulling are located on a line near and parallel to the radio cut-off in the 1gP-1gP diagram.
01 Jan 1981
TL;DR: In this paper, the authors used a simple method, the differentiation method, to calculate the expectation value of the IBM Hamiltonian in SU(6) and its three limiting cases used in refs. 2−4.
Abstract: Recently, Dieperink, Scholten, Iachello1 studied the shape, the shape phase transitions in the Interacting Boson Mode12–4 (IBM) by using the algorithm developed by Gilmore Feng5. They showed that each of the three limiting cases of the model corresponds to a certain shape phase. Each of the three transitional regions between the extreme cases are characterized by ground state shape phase transitions. However in constructing the classical limit they used somewhat simplified versions of the three limiting Hamiltonians originally employed by Arima Iachello2–4. In this note we use a simple method — the differentiation method — to calculate the expectation value of the IBM Hamiltonian in the coherent state. The classical limits of the most general IBM Hamiltonian of SU(6) as well as those of its three limiting cases used in refs. 2–4 are given.
TL;DR: For the Robertson-Walker metric for a homogeneous and isotropic universe, the authors derived explicit solutions of the Einstein-Yang equation (interior torsion-free solutions for a spinless ideal fluid) and hence found certain solutions for the radiation-dominated phase of the early universe.