Home About us Contact
|
Home About us Contact | ||
|
|
||
Min Decreased (min + decreased)
Selected AbstractsSeparation of light gas mixtures using SAPO-34 membranesAICHE JOURNAL, Issue 4 2000Joseph C. Poshusta Continuous SAPO-34 membranes were prepared on porous alumina tubular supports, and shown to be useful for light gas separations at low and high temperatures. Single-gas permeances of CO2, N2 and CH4 decreased with increasing kinetic diameter. For the best membrane at 300 K, the He and H2 permeances were less than that of CO2, because He, H2, and CO2 were small compared to the SAPO-34 pore, and differences in the heat of adsorption determined the permeance order. The smaller component permeated the fastest in CO2/CH4, CO2/N2, N2/CH4, H2/CH4 and H2/N2 mixtures between 300 and 470 K. For H2/CO2 mixtures, which were separated by competitive adsorption at room temperature, the larger component permeated faster below 400 K. The CO2/CH4 selectivity at room temperature was 36 and decreased with temperature. The H2/CH4 mixture selectivity was 8 and constant with temperature up to 480 K. Calcination, slow temperature cycles, and exposure to water vapor had no permanent effect on membrane performance, but temperature changes of approximately 30 K/min decreased the membrane's effectiveness. [source] The relationship between salivary secretion rate and masticatory efficiencyJOURNAL OF ORAL REHABILITATION, Issue 1 2004T. Ishijima summary, In order to elucidate the relationship between the salivary secretion rate and masticatory efficiency, experimental hypo- and hyper-salivation were produced by the administration of atropine sulphate presenting an anticholinergic effect and pilocarpine hydrochloride having a muscarine effect orally in 10 healthy fully dentates. To confirm the pharmaceutical effect of these drugs, the unstimulated whole salivary secretion rate during 10 min, and masticatory efficiency using the sieve method were measured before and after medication. The unstimulated whole salivary secretion rate during 10 min decreased significantly by the administration of atropine sulphate (P < 0·05), and increased significantly by pilocarpine hydrochloride (P < 0·01). The masticatory efficiency after atropine sulphate medication was significantly lower than that before (P < 0·01). The increase in salivary secretion by pilocarpine hydrochloride did not lead to a higher masticatory efficiency. The evidence supports the understanding that saliva plays an important role in masticatory function. [source] Rheological characteristics of suwari and kamaboko gels made of surimi from Indian major carpsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2002Thazhakot V Sankar Abstract The gel strength, compressibility and folding characteristic of suwari (set) and kamaboko (set and cooked) gels prepared from rohu (Labeo rohita), catla (Catla catla) and mrigal (Cirrhinus mrigala) surimi were examined to understand the occurrence of suwari and modori phenomena in surimi from major freshwater carps. Suwari setting of gels did not take place at lower temperatures. Suwari gels showed good gel strength at 50,°C for rohu and at 60,°C for catla and mrigal after 30,min setting time. Incubation for 60,min decreased the gel strength at 60,°C for rohu and catla. Setting at 25,°C followed by cooking at 90,°C increased the gel strength. Increased setting temperature, however, decreased the gel strength of cooked gels. Gel strength and compressibility data were supported by folding characteristics. © 2002 Society of Chemical Industry [source] Effects of Left Ventricular Assist Device on Cardiac Function: Experimental Study of Relationship between Pump Flow and Left Ventricular Diastolic FunctionARTIFICIAL ORGANS, Issue 9 2001Akira Saito Abstract: The left ventricular assist device (LVAD) with centrifugal pump has two characteristics. One is a pump flow wave of the centrifugal pump, consisting of the pulsatile flow of the native heart and the nonpulsatile flow of the centrifugal pump. The other is that the centrifugal pump fills from the native heart not only in the systolic phase, but also in the diastolic phase. In the case of the apex outlet LVAD with centrifugal pump, blood flows from the left atrium through the left ventricle to the pump. Pump flow is regulated by preload, and preload is regulated by diastolic hemodynamics. The aim of this study is to analyze the relationship between pump flow and the diastolic hemodynamics of the native heart. Ten anesthetized intact pigs were studied after placement of an LVAD. Data were recorded with the LVAD off (control) and the LVAD on. The assist rate was changed to 25%, 50%, and 75%. The indexes of left ventricular (LV) diastolic function included LV myocardial relaxation (time constant of isovolumic pressure decay [Tau] and maximum negative dP/dt[LV dP/dt min]) and LV filling (peak filling rate [PFR], time to peak filling rate [tPFR], and diastolic filling time [DFT]). Stroke volume decreased significantly in 75% assist. LV end-systolic pressure decreased significantly in 50% and 75% assist. LV end-diastolic volume decreased as assist rate increased, but there were no significant changes. Stroke work decreased significantly in 50% and 75% assist. LV dP/dt min decreased significantly in 50% and 75% assist. Tau prolonged as assist rate increased, but there were no significant changes. DFT shortened significantly in 75% assist. PFR increased significantly in 75% assist. tPFR shortened significantly in 50% and 75% assist. In this study, LV relaxation delayed as an increasing of pump assist rate, but it suggested a result of reduction of cardiac work. Also, it was suggested that LVAD increases the pressure difference between the left atrium and the left ventricle in the diastolic phase. This phenomenon is due to the filling of the left ventricle. In this study it was suggested that as pump assist rate increases, it is more effective to keep cardiac function in the diastolic phase. [source] | |||||||||||||