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71.
Cladosporium herbarum grown as a surface culture in a chemically defined medium of sucrose and inorganic salts gave a high yield of fat (29.2%). The component acids of this fat have been found to be palmitic (34.2%); oleic (15.9%); linoleic (34.2%) and linolenic (15.7%). The combined proportion of linoleic and linolenic acids being about 50 per cent, the fat will be of great value for the manufacture of oil-modified resins as the films produced by such resins do not become yellow with age.  相似文献   
72.
73.
At present Dhruva and Cirus reactors provide the majority of research reactor based facilities to cater to the various needs of a vast pool of researchers in the field of material sciences, physics, chemistry, bio sciences, research & development work for nuclear power plants and production of radio isotopes. With a view to further consolidate and expand the scope of research and development in nuclear and allied sciences, a new 20 MWt multi purpose research reactor is being designed. This paper describes some of the design features and safety aspects of this reactor.  相似文献   
74.
The costs of remedial work, and the radon level reduction achieved, have been studied in a series of domestic properties in Northamptonshire, which is a radon affected area. The cost-effectiveness of the series is similar to published theoretical estimates for proposed national remediation programmes, and five times more effective than our similar analysis for the National Health Service workplace, if it is assumed that 100% of householders discovering levels above 300 Bq m-3 implement remediation. In practice, in the UK, far fewer of those who arrange an initial radon test proceed to remediation, but this domestic programme could be cost effective if more than 5% carry out remediation. Our series confirms that a considerable number of householders with radon levels in the 200 to 300 Bq m-3 range do not seek or implement remediation work.  相似文献   
75.
76.
26 clinician trainees' recollections of experiences in a diagnostic preschool program were analyzed in terms of strength and weaknesses of the program.  相似文献   
77.
Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
78.
Determinants of research productivity   总被引:1,自引:0,他引:1  
Earlier researchers like Turkeli, suggested that ‘the factors which determine the productivity of scientists are admittedly complex and perhaps not amenable to real scientific analysis′. The present investigation was designed with the sole purpose of confronting such a complex problem. Nearly 200 variables influencing research productivity were collected through relevant literature, analysis of biographies of great scientists, and discussion with eminent scientists. Finally, through a critical examination, 80 variables were selected for the use of Q-sort technique. The sample for the study consisted of a cross section of scientists ranging from Fellows of Indian National Science Academy to young agricultural scientists. Mailed questionnaires and personal interview methods were used for collecting data. Out of a total of 912 respondents, reply was obtained from 325. On the basis of Q-sorted data, 26 variables were selected for further analysis and they were subjected to principal component factor analysis. The results indicated eleven factors affecting research productivity of scientists. They were: persistence, resource adequacy, access to literature, initiative, intelligence, creativity, learning capability, stimulative leadership, concern for advancement, external orientation, and professional commitment.  相似文献   
79.
1. Calcium disodium ethylenediaminetetraacetate (CaNa2 EDTA) and meso-2,3-dimercaptosuccinic acid (DMSA) individually and in permutation-combination in various doses (0.1, 0.2 and 0.4 mmol/kg bodyweight) were investigated for their efficacy to mobilize lead from vital tissues into urine and faeces and to restore the lead-sensitive biochemical parameters in lead pre-exposed rats with a view to develop the most acceptable treatment regimen for lead poisoning with a minimal loss of endogenous essential elements. 2. The combined therapy was more effective than a single chelator treatment. 3. The combination of 0.2 mmol/kg CaNa2EDTA + 0.4 mmol/kg DMSA caused a lower depletion of zinc, calcium and iron but possessed almost equal capability to that of 0.4 mmol/kg CaNa2EDTA + 0.4 mmol/kg DMSA to produce urinary as well as faecal excretion of lead, to reduce the tissue burden of lead, including that of the brain, and to reverse lead-induced biochemical alterations. 4. The combination of 0.2 mmol/kg CaNa2EDTA + 0.4 mmol/kg DMSA has shown a definite improvement over previously reported combinations in terms of removal of lead from tissues, particularly the brain, restoration of urinary delta-aminolevulinic acid levels and a decrease in the loss of body zinc and is, therefore, recommended for the treatment of lead intoxication.  相似文献   
80.
2014 aluminium alloy was subjected to various thermomechanical ageing (TMA) treatments which included partial peak ageing (25% and 50%), warm rolling (10% and 20%) and further ageing to peak hardness level at 160 ° C. The tensile tests reveal that TMA treatments cause a substantial improvement in tensile properties and thermal stability. The electron microscopic studies reveal that the TMA treatments affect substantially the ageing characteristics. The TMA Ib treatment yields the finest needles having longitudinal dimensions of 40nm. The TMA treatments also lead to precipitate-dislocation networks of different densities. It is observed that TMA IIb treatment results in the densest precipitate-dislocation tangles of all the TMA treatments. As a result, a significant improvement in the tensile properties of 2014 aluminium alloy has been observed.  相似文献   
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