Showing papers by "Henan Normal University published in 1993"
TL;DR: A population of rhesus macaques in the Taihang mountains on the Henan-Shanxi border is probably the northernmost population of the species as discussed by the authors, and the average group size is 82 individuals, and the population density is 3.1-7.2 individuals per km2.
Abstract: A population of rhesus macaques in the Taihang mountains on the Henan-Shanxi border is probably the northernmost population of the species. A more northerly population north of Beijing was locally extirpated in 1988. In the Taihang mountains, 26 natural groups, with >2000 monkeys, have been found. Six of them have been studied for 8 years. They live in a deciduous forest with temperate climate and cold snowy winters. The average group size is 82 individuals, and the population density is 3.1–7.2 individuals per km2. Home rangs are very large, varying from 11 to 22 km2. A natural reserve for the rhesus was established at Jiyuan in 1982, and one group, monitored and provisioned since 1984, has increased from 47 to 83 individuals, an increase of 76.5%.
34 citations
TL;DR: In this article, the standard free energies of transfer of KCl, NaCl, HC1, MgCl2 and CaCl2 from water to aqueous solutions of 5, 10, 15, 20, 25 and 30 Wt.
21 citations
TL;DR: In Britton-Robinson buffer, metronidazole is preconcentrated on a HMDE at 0.0 V (vs. AgAgCl) and an adsorptive stripping peak is observed at -0.62 V, which has been successfully applied to the determination of metronidsazole in human serum and formulations.
19 citations
TL;DR: In this paper, the positron lifetimes for the Y 1:2:3 oxygen-deficient system were reported and the local electron density and vacancy concentration were calculated as a function of Sn content.
Abstract: In this paper, we report positron lifetimes for ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Sn}}_{\mathit{x}}$${\mathrm{O}}_{\mathit{y}}$ (x=0\char21{}1.5). From these results, we calculate the local electron density ${\mathit{n}}_{\mathit{e}}$ and vacancy concentration ${\mathit{C}}_{\mathit{V}}$ as a function of Sn content. The results show a significant Sn-substitution dependence. At low x (\ensuremath{\le}0.4), ${\mathit{n}}_{\mathit{e}}$ decreases as x increases while at high x (\ensuremath{\ge}0.8) it reaches a constant value. For ${\mathit{C}}_{\mathit{V}}$, a large change occurs at x between 0.8 and 1.0 and corresponds to the known O-T phase transition. Positron experiments show that the structure of the Y 1:2:3 oxygen-deficient system is orthorhombic.
16 citations
TL;DR: The equations of motion for the p-polarization field in a four-layer heterostructure (FLHS) of polar crystals are solved exactly for the interface optical-phonon modes and the eigenvectors and the interface charge densities are obtained explicitly.
Abstract: The equations of motion for the p-polarization field in a four-layer heterostructure (FLHS) of polar crystals are solved exactly for the interface optical-phonon modes. The eigenvectors and the interface charge densities are obtained explicitly. The dispersion relations and their plots for a FLHS and its special cases, an asymmetric trilayer heterostructure (asymmetric single quantum well) and a step quantum well, are given and discussed. We find that there are six (not eight) frequency solutions for the interface optical-phonon modes in a FLHS and that, in the long-wavelength limit, the longitudinal and transverse modes in the two side materials 1 and 4 with frequencies (${\mathrm{\ensuremath{\omega}}}_{\mathit{L}1}$,${\mathrm{\ensuremath{\omega}}}_{\mathit{L}4}$,${\mathrm{\ensuremath{\omega}}}_{\mathit{T}1}$, and ${\mathrm{\ensuremath{\omega}}}_{\mathit{T}4}$) are forbidden (the four-layer structure comprises layers 1\char21{}4); two frequency solutions are obtained in their stead. These results are due to the asymmetry of the structure. Moreover, we also find that the situation in an asymmetric trilayer heterostructure is similar to that of a FLHS. This work can be regarded as a generalization of the formalism of Chen, Lin, and George [Phys. Rev. B 41, 1435 (1990)].
15 citations
TL;DR: A three-coil tungsten wire is used as electrode for the preconcentration of cadmium, which is then placed in a graphite tube for atomization and atomic absorption measurement and the recoveries for Cadmium are satisfactory.
13 citations
TL;DR: A comprehensive indicator combining the merits of quantitative and qualitative indicators is suggested and the ranking of the 32 countries by this indicator is found to follow also Zipf-Pareto distribution.
Abstract: The paper examines the qualitative as well as quantitative indicators for the assessment of the scientific publication activities of 32 countries, with special attention to the Zipf-Pareto distribution of those indicators. Also discussed is the linear relationship between the number of first authors of scientific papers in a given country and the number of papers it produced. Based on these discussions, a comprehensive indicator combining the merits of quantitative and qualitative indicators is suggested. The ranking of the 32 countries by this indicator is found to follow also Zipf-Pareto distribution.
10 citations
TL;DR: The proposed kinetic fluorimetric method is based on the catalytic oxidation of rhodamine 6G with potassium periodate in the presence of nitrilo triacetic acid as activator, in near neutral media and has been used to determine trace manganese in hair, urine, fish and water samples.
8 citations
Journal Article•
5 citations
TL;DR: In this article, the authors studied the positron lifetime spectrum for the orthorhombic to tetragonal phase transition and showed that the phase transition is a gradual changing process, in which the local electronic density has a large decreased and oxygen-vacancy have a large fluctuation which introduced a phase transition instability.
4 citations
TL;DR: In this paper, the enthalpies of solution have been measured for NaCl, KCl and KI in water and in acetone-water mixtures at 303.15 and 308.15 K. The enthalpic interaction parameters h xy, h xxy and h xyy of the three salts with acetone have been evaluated at the two temperatures.
TL;DR: It is found that this reagent can be used to identify Ag(+) and Hg(2+) and both of their sensitivities and selectivities are the best in all methods for the time being.
Journal Article•
TL;DR: A series of new 1-aroyl-3-(4-benzosulfonamidopyrimidine)-thioureas(1a～1) were syn-thesized by the reaction of aroylisothiocyanate with sulfadiazine in anhydrous acetonitrile as discussed by the authors.
Abstract: A series of new 1-aroyl-3-(4-benzosulfonamidopyrimidine)-thioureas(1a～1) were syn-thesized by the reaction of aroylisothiocyanate with sulfadiazine in anhydrous acetonitrile. Preliminarybiological tests indicate that some of compounds (1a～1) possess marked inhibiting activity againstcolibacillus, Bacillus subtilis, proteus and Staphylococcus aureus at concentration of 10ppm.
TL;DR: The symptoms and pathological changes of the two monkeys showed high similarity to esophageal cancer in humen, and it is believed that the present findings would provide important leads for further study to clarify the etiology and pathogenesis of human esophages disease in Taihang Mountain area.
Abstract: Taihang Mountain area, a high incidence area of human esophageal cancer in Northern China. 124 Rhesus monkeys (Macaca Mulatta) were caught in the area in January 1989. Among them, two monkeys died of esophageal carcinoma in 1990. Case 1, a male monkey about 6.5 years old and weighing 14.5 kg, had symptoms of salivation, vomiting and dysphagia in Fabruary 1990. The symptoms became gradually more serious and died in march 1990. Postmortem examination revealed a huge tumor in the distal segment of esophagus, causing severe structure of the organ. The tumor was classified as medullary type and histopathologically diagnosed as a well differentiated squamous cell carcinoma, with metastases to mediastinum and lymph nodes of right gastric group. Case 2, a female monkey ablut 11-year-old and weighing 10. 0 kg, showed loss of appetite, tiredness, somnolence, caughing and vomiting in September and died in December 1990. Autopsy revealed an annular tumor involving the whole cicumference of lower portion of the esophagus. The tumor was of ulcerative type and diagnosed as a well differentiated squamous cell carcinoma. The symptoms and pathological changes of the two monkeys showed high similarity to esophageal cancer in humen. We believe that the present findings would provide important leads for further study to clarify the etiology and pathogenesis of human esophageal cancer in this high incidence area of esophageal cancer.
TL;DR: In this article, a bulk Y124 high-Tc superconductor has been synthesized by solid state reaction of a mixture of Y 2 O 3, Ba(NO 3 ) 2 and micron size CuO at one atmosphere oxygen pressure with addition of NaNOβ.
TL;DR: In this article, the virtual effects from heavy PG bosons to the vertex were calculated in the framework of one generation technicolor model and the largest reduction from the charged PGB's and top quark to the partial width was while the maximum correction to the branching ratio was about 14%.
Abstract: In the framework of one generation technicolor model we calculated the virtual effects from heavy PG bosons to the vertex. Within parameter space the largest reduction from the charged PGB's and top quark to the partial width was while the maximum correction to the branching ratio was about 14%. From the comparison of theoretical. predictions with the corresponding data we are able to put an "primary" upper bound on the mass of for given .