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41.
The ways and forms of work of the All-Union and regional scientific societies of pathology in realization of the CPSU CC Degree "On Further Improvement of Ideological and Political Education Work" are discussed. It is suggested that the entire activity of the pathology societies be directed at the solution of the two main objectives extensive development and perfection of methodology of research work and direct participation of the pathology societies in the educational work among their members.  相似文献   
42.
Summary The sorption of sulfamethoxazole (SM) to crosslinked poly(N-vinyl-2-pyrrolidone) (CPVP) was studied by batch adsorption technique at pH's 1.0, 5.0 and 7.0 and at temperatures 10 and 30°C. Analysis by Scatchard method and Giles adsorption isotherm indicated that (i) the sorption increased in the order of pH, 7.0<1.0<5.0 and (ii) SM sorbed vertically through a monofunctional group. The peculiar sorption at pH 5.0 was explained in terms of CPVP — H2O interaction. The water-uptake by CPVP was minimum at pH 5.0 and increased at pH's 1.0 and 7.0.  相似文献   
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An investigation on the effect ofβ-cyclodextrin (CD) in both free and inclusion-complexed forms with a guest anionic metal complex, dioxalatodiaquochromate(III) (DDC), on the characteristics of conducting polyaniline (PANI) is carried out. Four materials, PANI (i.e. PANI-SO 4 2− ), PANI-DDC, PANI-CD and PANI-CD + DDC were prepared byin situ chemical oxidative polymerization in aqueous H 2SO4 at pH 1 and subjected to electrical conductivity and spectral (IR and UV-vis bd measurements. DDC and CD when separately incorporated, reduce the conductivity of PANI by about half whilst their inclusion complex CD + DDC enhances it. Spectral characterization reveals that DDC as a dopant and CD as an encapsule exhibit their effects through adverse interaction with imine-amine N centres and benzenoid moiety of PANI. The inclusion complex CD + DDC, on the contrary, functions as a dopant by lying in between the chains and seems to promote the extended conformation of PANI chain and hence theπ -electron delocalization. Exposure of the material to methanol vapour causes a decrease in conductivity in PANI and PANI-CD while an increase in PANI-CD + DDC. This study makes explicit the distinct role of CD as an encapsule and CD + DDC inclusion complex as a dopant in altering the electrical property of PANI.  相似文献   
44.
Global query execution in a multidatabase system can be done parallelly, as all the local databases are independent. In this paper, a cost model that considers parallel execution of subqueries for a global query is developed. In order to obtain maximum parallelism in query execution, it is required to find a query execution plan that is represented in the form of a bushy tree and this query tree should be balanced to the maximal possible extent with respect to execution time. A new bottom up approach called Agglomerative Approach (AA) is proposed to construct balanced bushy trees with respect to execution time. By the deterministic nature of this approach, it generates local optimal solutions. This local minima problem will be severe in the case of graph queries, i.e., queries that are represented with a graph structure. A Simulated annealing Approach (SA) is employed to obtain a (near) optimal solution. These approaches (AA and SA) are suitable for handling on-line and off-line queries respectively. A Hybrid Approach (HA), that is an integration of AA and SA, is proposed to optimize queries for which the estimated time to be spent on optimization is known a priori. Results obtained with AA and SA on both tree and graph structured queries are presented.  相似文献   
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In this work, biodiesel was produced from simarouba glauca seed oil through a two-stage acid-alkali esterification process. Concentrated sulphuric acid and sodium hydroxide were used as catalysts for acid and alkaline catalyzed esterification process, respectively. The free fatty acid content of the oil was reduced from 3.5 to 0.2%. The major properties of oil and its biodiesel were studied. Upon two-stage esterification, kinematic viscosity was reduced from 45.75 to 3.1 cSt and the acid value was reduced from 6.9348 to 0.4 mg KOH/g. The measured physio-chemical properties are within the limits set by ASTM biodiesel standards.  相似文献   
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To understand Cr emissions from slag melts to a vapor phase, an assessment of the stabilities of the chromium oxides at high temperatures has been carried out. The objective of the present study is to present a set of consistent data corresponding to the thermodynamic properties of the oxides of chromium, with special reference to the emission of hexavalent chromium from slags. In the current work, critical analysis of the experimental data available and a third analysis in the case of Cr2O3 have been carried out. Commercial databases, Fact Sage and ThermoCalc along with NIST-JANAF Thermochemical Tables, have been used for the analysis and comparisons of the results that are presented. The significant discrepancies in the available data have been pointed out. The data from NIST-JANAF Thermochemical Tables have been found to provide a set of consistent data for the various chromium oxides. An Ellingham diagram and the equations for the ΔG° (standard Gibbs free energy change) of formation of CrO x have been proposed. The present analysis shows that CrO3(g) is likely to be emitted from slag melts at high oxygen partial pressures.  相似文献   
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