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921.
Drying plays an important role in processing agricultural grains/seeds, chemicals, and other materials. In the present work, drying process has been analyzed taking published data on different grains and seeds such as rapeseed, sunflower, soybean, corn, paddy, and wheat. Mathematical expressions have been established for important drying parameters such as critical moisture content, drying rates, time required to reach critical moisture content, total drying time, and diffusivity as function of drying air temperature. The expressions involve a coefficient parameter and an exponential function of drying air temperature, Aexp(- E/RTg),and interestingly it is shown that the same functional form with same Es can correlate the different relevant drying parameters. The coefficient parameters As and Es are decided by drying materials and drying process, and the values have been derived for different grains/seeds. The correlations are useful in analyzing the drying process. 相似文献
922.
Computer architecture forms the bridge between application needs and the capabilities of the underlying technologies. As application demands change and technologies cross various thresholds, computer architects must continue innovating to produce systems that can deliver needed performance and cost effectiveness. Our challenge as computer architects is to deliver end-to-end performance growth at historical levels in the presence of technology discontinuities. We can address this challenge by focusing on power optimization at all levels. Key levers are the development of power-optimized building blocks, deployment of chip-level multiprocessors, increasing use of accelerators and offload engines, widespread use of scale-out systems, and system-level power optimization. 相似文献
923.
Microbial production of methionine is reviewed with 73 references. The review describes different methionine-producing organisms, as well as analog-resistant regulatory mutants, their optimum cultural conditions and yields. The pathways of methionine biosynthesis and their regulation are discussed. 相似文献
924.
The high-molar mass form of beta-glucosidase from Aspergillus niger strain NIAB280 was purified to homogeneity with a 46-fold increase in purification by a combination of ammonium sulfate precipitation, hydrophobic interaction, ion-exchange and gel-filtration chromatography. The native and subunit molar mass was 330 and 110 kDa, respectively. The pH and temperature optima were 4.6-5.3 and 70 degrees C, respectively. The K(m) and kcat for 4-nitrophenyl beta-D-glucopyranoside at 40 degrees C and pH 5 were 1.11 mmol/L and 4000/min, respectively. The enzyme was activated by low and inhibited by high concentrations of NaCl. Ammonium sulfate inhibited the enzyme. Thermolysin periodically inhibited and activated the enzyme during the course of reaction and after 150 min of proteinase treatment only 10% activity was lost with concomitant degradation of the enzyme into ten low-molar-mass active bands. When subjected to 0-9 mol/L transverse urea-gradient-PAGE for 105 min at 12 degrees C, the nonpurified beta-glucosidase showed two major bands which denatured at 4 and 8 mol/L urea, respectively, with half-lives of 73 min. 相似文献
925.
926.
A rapid assessment of drug abuse in Nepal was conducted at different sites, including eight municipalities in the five development regions of the country. To interview various groups of key informants, such methods as semi-structured interviews, in-depth interviews and focus group discussions were used. A snowball sampling strategy for respondents who were drug abusers and a judgemental sampling strategy for the non-drug-using key informants were applied. About one fifth of the sample was recruited from the treatment centres and the rest from the community. Drug abusers in prison were interviewed, and secondary data from treatment centres and prisons analysed. The study revealed that the sample of drug abusers had a mean age of 23.8 years and was overwhelmingly male. Most respondents lived with their families and were either unemployed or students. About 30 per cent of the sample was married. A large majority of the sample had a family member or a close relative outside the immediate family who smoked or drank alcohol and a friend who smoked, drank or used illicit drugs. Apart from tobacco and alcohol, the major drugs of abuse were cannabis, codeine-containing cough syrup, nitrazepam tablets, buprenor-phine injections and heroin (usually smoked, rarely injected). The commonest sources of drugs were other drug-using friends, cross-border supplies from India or medicine shops. The commonest source of drug money was the family. There has been a clear trend towards the injection of buprenorphine by abusers who smoke heroin or drink codeine cough syrup. The reasons cited for switching to injections were the unavailability and rising cost of non-injectable drugs and the easy availability and relative cheapness of injectables. About a half of the injecting drug users (IDUs) commonly reported sharing injecting equipment inadequately cleaned with water. Over a half of IDUs reported visiting needle-exchange programmes at two of the study sites where such programmes were available. Infection by the human immunodeficiency virus (HIV) appears to be low among IDUs, although systematic surveillance is absent. Two thirds of the sample had experienced sexual intercourse. The last sex partners reported by respondents were commercial sex workers, wives or girl friends. Condom use was low with primary partners and relatively high with sex workers. Treatment facilities, mostly located in the central urban areas of the country, are meagre. An overwhelming majority of drug abusers felt the need to stop abusing drugs. Cost-effective drug treatment and HIV prevention programmes for IDUs are urgently needed in all areas of the country. 相似文献
927.
S Chatterjee KK Mukherjee MC Mondal MS Chakrabrorty 《Canadian Metallurgical Quarterly》1996,45(3-4):279-283
A decade wide (from 1981 to the end of 1993) study on incidences of influenza was carried out in the city of Calcutta, India, by virus isolation and strain identification. Over 3500 patients with acute respiratory infections were examined and 1950 throat swab specimens were inoculated in embryonated chicken eggs. Only 339 haemagglutinating agents were isolated, which comprised 233 strains of influenza A virus. One hundred forty six (62.66%) of these strains were identified as H3N2, eighty one as H1N1 (34.76%), and only two were H2N2 (0.86%) strains of influenza A viruses, as estimated by haemagglutination inhibition test. This observation indicates that H3N2 is the major prevalent strain followed by H1N1 strains of influenza A virus in Calcutta. 相似文献
928.
SS Chatterjee SK Bhattacharya M Wonnemann A Singer WE Müller 《Canadian Metallurgical Quarterly》1998,63(6):499-510
We demonstrate that the phloroglucinol derivative hyperforin is not only the major lipophilic chemical constituent of the medicinal plant Hypericum perforatum (St. John's wort) but also a potent uptake inhibitor of serotonin (5-HT), dopamine (DA), noradrenaline (NA), GABA and L-Glutamate with IC50 values of about 0.05-0.10 microg/ml (5-HT, NA, DA, GABA) and about 0.5 microg/ml (L-glutamate) in synaptosomal preparations. Furthermore, potencies of two different hypericum extracts in two conventional pharmacological paradigms useful for the detection of antidepressants (behavioral despair, learned helplessness), closely correlate with their hyperforin contents. In addition, most till now known neuropharmacological properties of the clinically used hypericum extracts can also be demonstrated with pure hyperforin. It appears, therefore, that this non-nitrogenous constituent is a possible major active principle responsible for the observed clinical efficacies of the extract as an antidepressant and that it could also be a starting point for drug discovery projects engaged in the search of psychoactive drugs with novel mode of action. 相似文献
929.
C Grimm B Chatterjee J Favor T Immervoll J L?ster N Klopp R Sandulache J Graw 《Canadian Metallurgical Quarterly》1998,23(4):299-316
The homozygous mouse mutant aphakia (ak) has been characterized by bilaterally aphakic eyes without a pupil [Varnum DS, Stevens, LC (1968): J Hered 59:147-150]. The mutation was mapped to chromosome 19 [Varnum DS, Stevens, LC (1975): Mouse News Lett 53:35]. Our linkage studies yielded a precise localization of the ak gene 0.6 +/- 0.3 cM proximal to the microsatellite marker D19Mit10 and 0.7 +/- 0.4 cM distal to D19Mit4 and D19Mit91. No recombination was found with the marker D19Mit9 among 418 backcross offspring tested. The developmental control gene Pax2 mapped 11.0 +/- 3.5 cM proximal to ak and is excluded as a candidate gene. Sequence analysis of Fgf8 and Chuk1, which are localized close to the marker D19Mit10, detected no mutations in the ak/ak mutants. Histological analysis of homozygous mutants suggested the arrest of lens development at the lens stalk stage, a transient morphological structure during the formation of the lens vesicle. In the lens remnants, Pax6 and Six3 are expressed, whereas in the persisting lens stalk only Pax6 was detected. The expression pattern of Pax2 appeared normal; Cryaa expression could not be detected. As a consequence of the arrested lens development, other ocular tissues that require for their development information from the intact lens, such as iris, ciliary muscle, retina, and vitreous body, are absent or formed abnormally. 相似文献
930.
The position in India on the phosphorus front vis-a-vis iron and steel operations elsewhere in the world is, and will remain,
most unfavourable since Indian iron ores contain high phosphorus and coal (and therefore, also the coke), has high ash and
phosphorus in the Indian subcontinent. While dephosphorization of hot metal is theoretically ruled out in the Indian context,
dephosphorization of liquid steel can also not be considered because of its adverse effect on ladle refractories and steel
cleanliness.
For a large proportion of the steels made through the LD-slab caster-hot strip mill route at Tata Steel, the phosphorus content
required in the product is 0·020% max and in some grades, it is restricted to 0·015% max. Various control strategies evolved
to make low phosphorus steel at Tata Steel are discussed in the paper. The major steps which have significantly reduced the
phosphorus levels are described. 相似文献