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801.
Ingvar Holmér 《东华大学学报(英文版)》2006,23(5):54-58
The water vapour resistance of clothing ensembles is not as commonly determined as dry thermal insulation. The measurement techniques are more complicated and the measurement values differ among laboratories. Due to complicated moisture transfer process through clothing ensemble, the moisture absorbed and evaporated varies in transient and steady state phases depending on properties, thickness of clothing, and environmental conditions. The purpose of this study was to measure moisture gain inside hygroscopic underwear, and hydrophobic and permeable outer wear as a function of time, to investigate mass loss from "skin" as well as from the manikin, to quantify evaporative heat loss and total heat loss from the manikin, and to determine water vaponr resistance of clothing. Manikin Tore was used by wearing wet "skin" to simulate sweating condition. Moisture content in the inner garment gain shows an exponential relation against time. Moisture in the outer permeable layer shows little gain. On the contrary, mass loss directly from the wet skin decreases exponentially. The mass loss from the manikin is relatively stable throughout three test phases. The evaporative heat loss is about 2/3 of the total heat loss from the sweating manikin. While measuring the evaporative resistance of clothing ensembles with hygroscopic inner garment and permeable outer garment, unlike to measure ensembles with impermeable outer layer, one hour measurement time is enough to get relatively stable results. The variation between the 1^rt hour and the 3^nd hour is less than 5%. The length of transient period and measurement time is dependent on the permeability, thickness of clothing ensembles and environmental conditions. 相似文献
802.
New class of glutamate agonist structurally related to ibotenic acid 总被引:20,自引:0,他引:20
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807.
Natural antibody production in human tonsils 总被引:1,自引:0,他引:1
Zusammenfassung Es konnten in den aus den Tonsillen gewonnenen Lymphozyten natürliche, Antikörper bildende Zellen nachgewiesen werden. 相似文献
808.
N. R. Banna N. E. Saadé C. Salameh S. J. Jabbur 《Cellular and molecular life sciences : CMLS》1981,37(1):83-84
Summary In spinal unanesthetized cats, pyridoxine pretreatment significantly enhanced the diazepam-induced increase in dorsal root potentials and dorsal root reflexes.Acknowledgments. This work was supported by a grant from the Lebanese National Research Council. The authors wish to thank Mr M. Shakarji for technical assistance in this investigation. 相似文献
809.
B de Néchaud A Viron E Puvion 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,289(10):737-740
Adult mouse liver cells obtained by enzymatic dispersion were maintained in primary cultures for up to 4 weeks. They retained some of the typical morphological and ultrastructural characteristics of hepatocytes. After 2 days of culture, structures similar to bile canaliculi were found and after 6 days clusters of small proliferating cells were noticed in the gaps of the monolayer formed by large well-spread hepatocytes. Almost all 3-day cultures began to secrete alphafetoprotein for about 2 weeks, whereas albumin was secreted throughout the period of culture. 相似文献
810.