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81.
We have measured the heat capacities of3He films and liquid3He in porous Vycor glass at 10 to 600 mK. With increasing the film thickness from 1 to 3 atomic layers, the specific heat evolves gradually from that typical to solid to that of liquid3He. At about 2 atomic layers, however, its low-temperature part is nearly temperature-independent; we interpret this as a result of gradual freezing of spins in an amorphous solid3He film with decreasing the temperature. The contribution of liquid3He in the center of the Vycor pores can be described as the specific heat of bulk liquid3He at corresponding pressures in the range 0 to 28 bar. The thickness of amorphous solid on the pore walls increases with external pressure roughly linearly. Preplating the walls with4He allows to determine the positions of3He atoms contributing to the surface specific heat at 10 to 50 mK. In addition, the contribution from the specific heat of3 He -4He mixing at 100 to 600 mK is discussed as a function of pressure and amount of4He.0n leave from ISSP Acad. Sci. of Russia, Chernogolovka, Russia 相似文献
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Frank V. Kosikowski 《Journal of dairy science》1985,68(9):2403-2410
Ultrafiltration and thermization of milk on dairy farms in France have been under study since 1979. More recently five dairy farms in Brittany have been routinely producing 2:1 whole milk retentate for Emmental and St. Paulin cheese making. The milk processed is ultrafiltered at 35°C and thermized at 72°C for 15 s in an Ultratherm unit. Cheese quality generally appears satisfactory.In Eastern France a new specialty cheese industry has been started utilizing 4.5:1 whole milk retentate produced by ultrafiltration conducted at 40°C. The specialty cheese attains its characteristic white surface from Penicillium album mold. It has a bland, nutty flavor and very soft, smooth texture. A surface bluing phenomenon occurs after 14 d. 相似文献
84.
着重介绍Raychem电路保护部的PolySwitch PPTC(聚合物正温度系数)元件在电源管理中提供电流过载和温度过载的保护过程。另外还介绍了电源适配器、CLA(点烟器)、移动电话设备及电池板的保护装置是如何进一步改善实际使用中的总体可靠性的。 相似文献
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Nickel molybdate catalysts used in several different upgrading reactions of coal-derived materials from low-rank Australian coals have been regenerated and their activity assessed using a number of physical and chemical techniques. Regeneration of spent coked catalysts for 20 hours in air at 450°C was sufficient to restore chemical hydrogenation activity to catalyst used for pre-asphaltene, asphaltene and oil upgrading, provided poisoning of the catalyst surface by other impurities, principally chlorine-containing molecules, had not occurred. 相似文献
88.
MG Narducci L Virgilio JB Engiles AM Buchberg L Billips A Facchiano CM Croce G Russo JL Rothstein 《Canadian Metallurgical Quarterly》1997,15(8):919-926
In human leukemias and lymphomas nonrandom chromosomal rearrangements cause changes in cell growth and/or survival in such a way as to promote malignancy. The detailed study of the biochemical and genetic pathways altered in human cancer requires the identification or development of models to allow the study and manipulation of cancer gene function. Recently, the breakpoint gene TCL1, involved in chromosome translocations observed mostly in mature T-cell proliferations and chronic lymphocytic leukemias (CLL), was isolated and characterized, and showed to be part of a new gene family of proteins involved in these tumors. The murine Tcl1 gene, is similar in sequence to the murine and human MTCP1 gene also involved in T cell leukemias. The murine Tcl1 gene was shown to reside on mouse chromosome 12 in a region syntenic to human chromosome 14. Furthermore, we show that the murine Tcl1 gene is expressed early in mouse embryonic development and demonstrates expression in fetal hematopoietic organs as well as in immature T and B cells. Characterization of the murine Tcl1 gene will help in developing a mouse model of CLL and would provide the best opportunity to study and decipher the role of TCL1 in malignant transformation. 相似文献
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