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1.
The electrical properties and microstructure of (Ba,Y)TiO3 PTCR ceramics were studied. The results indicate that the Mn ions increase the intergranular barrier height and produce a high-resistance layer on the grain surface. The temperature-dependent resistances of the grain bulk, surface layer, and grain boundaries, the temperature coefficient of resistance, and the magnitude of the varistor effect were assessed as a function of Mn content. 相似文献
2.
A. N. Gudkov V. M. Zhivun A. V. Zvonarev V. V. Kovalenko A. B. Koldobskii Yu. F. Koleganov S. V. Krivasheev V. B. Pavlovich N. S. Piven' E. V. Semenova 《Atomic Energy》1989,66(2):115-118
Translated from Atomnaya Énergiya, Vol. 66, No. 2, pp. 100–103, February, 1989. 相似文献
3.
NW Tomkins NN Jonsson MP Young AN Gordon KA McColl 《Canadian Metallurgical Quarterly》1997,75(10):722-723
On the basis of clinical signs and histological findings eight 9-month-old male rusa deer (Cervus timorensis) were diagnosed with sheep associated-malignant catarrhal fever. Following a variable course involving rectal temperatures around 40.5 degrees C, depression, inappetence, diarrhoea, corneal opacity and hypopyon all animals died or were euthanased over a 5-week period. Severe multifocal vasculitis, mainly periglomerular and in the arcuate vessels were consistent histological findings which in the past have been adequate to confirm clinical diagnosis of sheep associated-malignant catarrhal fever. A nested polymerase chain reaction test has been used to detect a sheep associated-malignant catarrhal fever PRC product, 238 base-pairs in size, in DNA extracted from lymphocyte preparations. The result supported the diagnosis of sheep associated-malignant catarrhal fever in these deer. 相似文献
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5.
NV Zheleznova SL Mukomolov AB Zhebrun FS Noskov II Malkova EP Shargorodskaia AD Al'tshte?n VA Pliutnikova IN Lavrent'eva NN Ptichnikova 《Canadian Metallurgical Quarterly》1996,(5):49-53
The use of a recombinant poxvirus (RPV) strain, expressing HBsAg in the process of reproduction in different bioreactor systems under stationary and bioreactor conditions of cultivation, made it possible to obtain highly purified HBsAg. The identity and purity of HBsAg was confirmed by the analysis of its amino acid composition, SDS electrophoresis in polyacrylamide gel, electron microscopy and high-performance liquid chromatography. Good prospects of the use of RPV-expressed gene engineering HBsAg as the basis vaccines against hepatitis B was demonstrated in 10 experimental batches of vaccine. All batches of the preparation had pronounced immunogenicity and were safe and nontoxic in animal experiments. The ID50 of experimental batches did not exceed 211 ng/ml, which, according to the data of comparative experiments, was lower than, or equal to, corresponding values of analogous foreign commercial preparations, based on plasma or yeast HBsAg. 相似文献
6.
NN McGihon 《Canadian Metallurgical Quarterly》1996,34(6):31-35
1. Most psychiatric and mental health professionals are experienced with writing in some form as a tool for encouraging patients to express feelings and identify stressors. 2. Narrative writing, or journal writing, can also help patients identify areas of conflict in their lives and to clarify complicated issues. 3. Writing can be used effectively with patients who are reluctant or embarrassed to speak openly in one-on-one interactions. 相似文献
7.
N S Sergeeva M Iu Vasil'ev T I Kovalenko N V Sokolova G I Avdeev 《Eksperimental?nai?a onkologii?a》1989,11(2):35-37
The indirect immunofluorescent technique was used to study the distribution of the ascitic fluid antigen (AgD) on histological sections from surgical specimens of gastric and colon tumours from proximal to distal lines of resection. AgD was found in gastric tumours exceptionally in the tumour area and in colon cancer--both in the tumour stroma and in surrounding histologically normal mucosa. 相似文献
8.
A theoretical study is reported of the magnetic-field-controlled optical transmission through a stack of identical bilayers in which one layer is bigyrotropic and the other is nonmagnetic and isotropic. An analytical expression for the complex transmittance is derived. The transmittance–wavelength characteristic is examined for different magnetizations and for fixed materials parameters and total number of bilayers. The magnetization dependence of the position, height, and width of the center peak is investigated. The effect is calculated of magnetization on the ellipticity of transmitted light and the angle of optical rotation. 相似文献
9.
10.
L. A. Kryachko V. N. Paderno O. I. Kovalenko 《Powder Metallurgy and Metal Ceramics》1992,31(6):510-518
Translated from Poroshkovaya Metallurgiya, No. 6(354), pp. 58–69, June, 1992. 相似文献