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991.
Raffaele G. Ruberto 《Fuel Processing Technology》1980,3(1):7-24
To study the fate of the solvents in the non-catalytic liquefaction of Kentucky bituminous coal, a number of batch liquefaction experiments have been carried out using hydrophenanthrenes and coal-derived hydrogenated recycle solvents. Filtrates from the first runs have been rehydrogenated and used as solvents for additional liquefaction experiments. The reactions have been followed by detailed analysis of the feeds and products.At constant temperature and reaction time, the conversion levels are affected by the amount of transferable hydrogen, Hs (up to a value of about 0.6 wt.% of the feed), by the coal concentration and, to a lesser extent, by the pressurizing gas.The solvents are depleted by isomerization, cracking, and adduction-polymerization reactions. Only about 50% of the initial solvent is available for use in the second-pass runs. In addition, the quality of the second-pass solvents is lower than that of the initial solvents due to a decrease of 6-membered hydroaromatic rings and an increase of 5-membered hydroaromatic rings which are poor hydrogen donors. 相似文献
992.
Luigi Cavenaghi Gian Gualberto Gallo Gian Marco Leali Silvano Vianello 《Drug development and industrial pharmacy》1987,13(14):2571-2615
To improve the way by which the quality control of medicines is carried out, general statistical concepts and methods are discussed for the evaluation of the analytical results obtained for judging the adequacy of drug substances and products for Pharmacopoeia requirements.
Statistical procedures to be adopted by the producer and the controller in the determination of characteristics are suggested when the drug substance is or is not homogeneous and when the precision of the analytical method is known or unknown.
For each of these cases, detailed numerical examples are given. 相似文献
Statistical procedures to be adopted by the producer and the controller in the determination of characteristics are suggested when the drug substance is or is not homogeneous and when the precision of the analytical method is known or unknown.
For each of these cases, detailed numerical examples are given. 相似文献
993.
994.
Objectives of this trial were to evaluate effects of rbST on the nutritional status of 24 Holstein cows during pregnancy and of their calves from birth to weaning. All cows conceived during injection with either a placebo or 350 mg of rbST in a sustained-release vehicle every 14 d commencing 98 to 112 d postpartum for their entire lactation. In Experiment 1, blood samples were collected at 90, 180, and 270 d postconception in cows. Concentrations of urea, glucose, albumin, total proteins, Ca, P, insulin, cortisol, hemoglobin, and hematocrit were unaffected by treatment as well as BW, body condition scores, and energy balances at conception and during pregnancy. Days open and calving interval were not significantly different but were numerically increased by 31 d in rbST-injected cows. Nonesterified fatty acids, bST, and insulin-like growth factor-I in plasma were elevated significantly in rbST-injected cows. In Experiment 2, blood samples were collected at birth and at 1, 3, 5, and 7 wk in calves born from cows of Experiment 1. Circulating concentrations of glucose, nonesterified fatty acids, albumin, total proteins, hemoglobin, insulin, cortisol, bST, insulin-like growth factor-I, and hematocrit, blood pH, blood gases and buffer capacity, birth weight and rate of weight gain, height at withers, and heart girth from birth to weaning were not different due to treatment of dam. However, some parameters were significantly different based on age and sex. These data support previous assumptions that the magnitude of the modifications in nutrient partitioning produced by rbST do not affect the hierarchy of the partitioning process for the calf. 相似文献
995.
996.
An algorithm for theorem proving in differential geometry based on the calculation of the differential dimension of differential quasi-algebraic sets is shown. In the case in which only ordinary differential equations are involved, an algorithm for such computation is presented. Different notions of validity for differential geometry statements are also compared.This paper was supported by Italian M.P.I. (40% 1985). 相似文献
997.
Raffaele Savino Chiara Piccolo Raimondo Fortezza Yoshiyuki Abe 《Microgravity science and technology》2007,19(3-4):75-77
The work presents experimental tests about the performance of heat pipes filled with a “self-rewetting“ fluid (alcohol aqueous solutions). Comparison with conventional commercial water heat pipes is also considered. The used fluid exhibits an anomalous increase in the surface tension with increasing temperature. Along these lines, the fluid has been investigated as a possible means to improve heat transfer inside the heat pipes with a focus, in particular, on space applications (next generation satellites). The experiments have been carried out both in normal and in low-gravity conditions (attained onboard a ‘zero-g’ plane, during a parabilic flight campaign). The results have confirmed improved capability of the considered heat pipes with respect to traditional heat pipes filled with water. 相似文献
998.
Gallo David A.; Chen Jennifer M.; Wiseman Amy L.; Schacter Daniel L.; Budson Andrew E. 《Canadian Metallurgical Quarterly》2007,21(5):559
This study explored the relationship between episodic memory and anosognosia (a lack of deficit awareness) among patients with mild Alzheimer's disease (AD). Participants studied words and pictures for subsequent memory tests. Healthy older adults made fewer false recognition errors when trying to remember pictures compared with words, suggesting that the perceptual distinctiveness of picture memories enhanced retrieval monitoring (the distinctiveness heuristic). In contrast, although participants with AD could discriminate between studied and nonstudied items, they had difficulty recollecting the specific presentation formats (words or pictures), and they had limited use of the distinctiveness heuristic. Critically, the demands of the memory test modulated the relationship between memory accuracy and anosognosia. Greater anosognosia was associated with impaired memory accuracy when participants with AD tried to remember words but not when they tried to remember pictures. These data further delineate the retrieval monitoring difficulties among individuals with AD and suggest that anosognosia measures are most likely to correlate with memory tests that require the effortful retrieval of nondistinctive information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Petrovic S Pascolo L Gallo R Cupelli F Ostrow JD Goffeau A Tiribelli C Bruschi CV 《Yeast (Chichester, England)》2000,16(6):561-571
Since bilirubin-like pigments are present in the environment as degradation products of heme-containing proteins, yeast could have developed a detoxifying system to transport these compounds into their vacuoles. Vacuoles from Saccharomyces cerevisiae showed an ATP-dependent, saturative transport of unconjugated bilirubin (UCB) that was reduced by 60% and 40% in YCF1 and YLL015w-deleted cells, respectively; the double deletant showed no UCB uptake. Conversely, the transport of bile acids (taurocholate) was comparable in wild and deleted stains. These data identify YCF1 and YLL015w, named BPT1 (Bile Pigment Transporter), as the genes responsible for ATP-dependent UCB transport in yeast. Since YCF1 and YLL015w are rather homologous with multidrug resistant proteins (MRPs), they also suggest the involvement of this class of transporters in the ATP-dependent transport of unconjugated bilirubin. 相似文献
1000.
A new class of PLGA‐based materials suitable for the production of biodegradable NPs via free‐radical polymerization is proposed. ROP of lactide and glycolide using HEMA is carried out; macromonomers (HEMA‐LxGyA) with short PLGA chain ends are successfully produced. Afterwards, monomer‐starved semi‐batch emulsion polymerization of these HEMA‐LxGyA macromonomers is performed to obtain NPs with a low polydispersity index and a controlled size. The stability and degradability of NPs is confirmed from degradation studies that verify the possibility of tuning the degradation time by changing macromonomer characteristics such as chain length and composition.