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991.
Using methods of mathematical statistics (cluster, dispersion, and correlation analyses), the impact strength of three types of glass containers (bottles and jars) was analyzed. Three temperature regions in which molding results in very different values of the strength of the articles are revealed. The boundaries of the molding temperature regions are critical regardless of the type of article molded and are probably only determined by the chemical composition of the glass melt. The preferred mold temperature range is 480–550°C. The results of the study are interpreted based on an analysis of the features of molding glass at different temperatures. __________ Translated from Steklo i Keramika, No. 2, pp. 3–7, February, 2007.  相似文献   
992.
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994.
Interface oscillations during boiling are studied experimentally and theoretically. The output-signal spectra of light and acoustic sensors indicate that the liquid-pressure and interface oscillations are interrelated. A model is suggested for the oscillations of a bubble growing on a heating surface, and the existence of an attractor is deduced for the first time from the solution of model equations. The data obtained enable one to determine the ranges of interface oscillation amplitude and frequency and can be used in the modeling of boiling.  相似文献   
995.
Kuemmel DF  Chapman LR 《Lipids》1968,3(4):313-316
The monoenoic methyl esters from numerous fats and oils which contained appreciablecis-9-hexadecenoic acid (cis-9-16∶1) were isolated by liquid-solid chromatography on silver nitrate-silica gel. Analysis of the monoenes by packed and capillary column gas-liquid chromatography showed that significant amounts ofcis-11-octadecenoic acid (cis-11-18∶1) were present in all samples. The amount ofcis-11-18∶1 found in the monoenoic methyl esters increased proportionally to logarithmic increases in thecis-9-16∶1 level. Most analyses reported in the literature also show this proportionality. This mathematical relationship suggests that chain elongation ofcis-9-16∶1 tocis-11-18∶1 is a biosynthetic pathway operative in a wide variety of species.  相似文献   
996.
997.
Conclusions The type of orthophosphoric acid has the maximum influence on the properties of corundum concretes, a lower influence on high-alumina concretes, and practically no influence on quartz-clay concretes. It is desirable to use wet-process orthophosphoric acid for refractory concretes. The excellent properties of concretes in the system A12O3-SiO2 based on this acid which is also cheaper enabled us to recommend it for preparing refractory concretes.The advantage of using H3PO4 of various types for corundum concretes is determined by the requirements placed on them in actual working conditions.Translated from Ogneupory, No.6, pp. 58–61, June, 1970.  相似文献   
998.
Alkyl lysophospholipids have been shown to be cytooxic to a number of neoplastic tissues. One, ET-18-OCH3, has been used to selectively purge leukemic cells from mixtures with normal marrow progenitor cells,in vitro andin vivo. We have measured the 50% inhibitory (IC50) effect of a series of ether, lipids (EL) on leukemic cells (HL60, K562, Daudi, KG-1, KG-1a) and normal marrow progenitor cells. Cells were incubated with varying concentrations of EL for 4 hr and assayed for viability, [3H]thymidine incorporation and clonogenicity in semi-solid media. The effect on protein kinase C (PKC) activity was assayed for each compound. Compounds tested included three glycerophosphocholine analogs-ET-18-OCH3, ET-16-NHCOCH3, and BM 41.440. In addition, a lipoidal amine, CP 46665, an ethyleneglycolphospholipid, AEPL, and four single chain alkylphosphocholine analogs, HePC2, HePC3, HePC4 and HePC6 were also tested. During the period of incubation, the cells remained viable (>70%) as judged by trypan blue dye exclusion. The glycerophosphocholines were the most active and showed the highest therapeutic index. The lipoidal amine was active, but toxic to normal marrow progenitor cells. The ethyleneglycolphospholipid was active against HL60, but not against the other cell lines. The single chain alkylphosphocholine analogs were less active. All of the compounds inhibited PKC activity; however, the glycerophosphocholines were the most inhibitory. Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989.  相似文献   
999.
1000.
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