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排序方式: 共有1392条查询结果,搜索用时 15 毫秒
1.
Galin Ivanov Ertugrul Bilgucu Ivelina Ivanova Milena Dimitrova 《International Journal of Dairy Technology》2020,73(3):563-569
The present study aimed to investigate the effect of somatic cell count (SCC) of raw cow's milk on the volatile organic compound (VOC) profiles of yoghurt. Test yoghurt samples were produced from three batches of cow's milk with low, medium and high SCC, respectively. The VOCs were determined by gas chromatography–mass spectrometry (GC–MS) analysis. A lower diacetyl and acetoin content and a higher content of 2‐heptanone, and butanoic and hexanoic acids were established in the yoghurt samples from batches with high SCC of above 1 000 000 cells/cm3. The increased SCC of cow's milk had a negative effect on the volatile organic compound profiles of yoghurt. 相似文献
2.
Z Dimitrova Dimitrova VG Dumanov G Ivanova Petrova 《Canadian Metallurgical Quarterly》1997,67(2-3):73-79
Registered psychiatric morbidity in Bulgaria as a whole and particularly in Plovdiv, the second largest region of the country, was assessed. Three aspects of psychotropic drug usage were analysed, namely, changes in registered psychotropic drugs, the prescribed daily dose (PDD) values for 2 years, and the preferred therapeutic schemes, and drug usage and needs in a psychiatric hospital with 365 beds. This was done by time series analysis for evaluation of psychiatric morbidity and drug consumption data, calculation of PDD for psychotropic medicines, and, based on a modification of the World Health Organization's morbidity method, assessment and prediction of drug use and needs in Plovdiv hospital. The results indicated that the registered morbidity had increased by 4% over the period 1989-93 to 2,427 psychiatric patients per 100,000 people. The increased consumption of especially benzodiazepines and sedative medicines was analyzed. Diazepam was prescribed the most often (91.1%), followed by levomepromazine (86.4%), haloperidol (82.7%), etc. Future drug consumption in Plovdiv hospital is expected to decrease because therapeutic practice in hospitals has been revised and improved on the basis of the World Health Organization's recommendations. 相似文献
3.
A. Andreev L. Prahov M. Gabrovska A. Eliyas V. Ivanova 《Applied catalysis. B, Environmental》1996,8(4):365-373
The catalytic activity of a wide range of transition metal oxides in oxidation of sulphide ions by air in aqueous medium was studied. Some specific features of the reaction mechanism on some of the studied oxides were considered. The transition metal oxides are promising catalysts for practical application. Some of these oxides will allow the preparation of catalysts possessing activity comparable to that of the cobalt phthalocyanine based catalysts, popular in industrial practice. 相似文献
4.
5.
I. V. Shcherbatenko E. P. Ivanova V. I. Surikov 《Chemical and Petroleum Engineering》2007,43(5-6):335-342
A method is proposed for calculating the optimum density of lattice of blades of screw pump impeller that ensures, for a given
cavitation margin (inlet pressure), the first critical condition on the partial cavitation characteristic of the pump. The
equations obtained can be used also to calculate the permissible cavitation margin of screw centrifugal and screw mixed-flow
pumps as well as of stand-alone screw impeller, provided the geometric and operating conditions of the screw are given.
__________
Translated from Khimicheskoe i Neftegazovoe Mashinostroenie, No. 6, pp. 29–33, June, 2007. 相似文献
6.
E. A. Ivanova D. F. Kasatkin L. A. Akishina E. V. Nepomnyashchaya 《Chemistry and Technology of Fuels and Oils》1992,28(5):241-243
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 5, pp. 2–3, May, 1992. 相似文献
7.
8.
N. I. Ivanova V. V. Kharitonov V. E. Ivanov 《Journal of Engineering Physics and Thermophysics》1992,63(2):766-768
Optimum conditions for cementing prepared roofing paper are determined and an installation for laying prepared roofing paper as a hydroinsulating roofing carpet is designed.Gomel Polytechnic Institute. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 63, No. 2, pp. 151–153, August, 1992. 相似文献
9.
The main problems in estimating the uncertainty due to the presence of impurities in the material: the absence in the documents of a unique definition of the quantity being measured – the fixed point temperature, the lack of agreed methods of realizing the fixed points and the insufficient justification of the equations used for the estimate, are analyzed. The results of a measurement of the melting point of gallium are presented, which differ in the conditions in which they were realized – with one and two liquid-solid interfaces and different solidification conditions, are presented. The reasons for the considerable difference between the values of the temperatures obtained in these experiments are discussed. 相似文献
10.
A model is developed in which the theory of deterministic chaos for the interface layer is used to treat both homophase and heterophase fluctuations of density (volume) and the fluctuations of pressure, whose duration increases as the critical point is approached. This approach, based on the transition from continuous differential equations to mappings, leads to a number of important consequences in theoretical analysis of high-temperature processes of evaporation and condensation, including the loss of information on the initial conditions, the alternation, and the presence of branching points on bifurcation diagrams. 相似文献