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141.
A non-ionic water-soluble galactomannan, having galactose and mannose in 1:6 molar ratio, was isolated from endosperm of the seeds of Ipomoea dasysperma. The seed mucilage was found to have a structure having a linear chain of beta (1-->4) linked mannopyranosyl units with D-galactose side chains attached through alpha (1-->6) linkage to the main chain. I. dasysperma seed gum possesses non-ionic characteristics of commercial seed gums and has potential to be used in food and pharmaceutical industries. 相似文献
142.
Megabase-scale mapping of the HLA gene complex by pulsed field gel electrophoresis 总被引:18,自引:0,他引:18
S K Lawrance C L Smith R Srivastava C R Cantor S M Weissman 《Science (New York, N.Y.)》1987,235(4794):1387-1390
In the study of the genetic structure of mammalian chromosomes, there exists a "resolution gap" between molecular cloning experiments and meiotic linkage analyses. This gap has discouraged attempts to construct full-scale genetic maps of mammalian chromosomes. The organization of the human major histocompatibility complex was examined within this range by pulsed field gel electrophoresis. The data obtained indicate that the complex spans over 3000 kilobases and enable the construction of a megabase-scale molecular map. These results indicate that the techniques employed in DNA extraction, enzymatic digestion, electrophoresis, and hybridization are suitable for the efficient analysis of megabase regions of mammalian chromosomes and effectively bridge the resolution gap between molecular cloning and classical genetics. 相似文献
143.
144.
The production of strings (disclination lines and loops) has been observed by means of the Kibble mechanism of domain (bubble) formation in the isotropic-nematic phase transition of the uniaxial nematic liquid crystal 4-cyano-4'-n-pentylbiphenyl. The number of strings formed per bubble is about 0.6. This value is in reasonable agreement with a numerical simulation of the experiment in which the Kibble mechanism is used for the order parameter space of a uniaxial nematic liquid crystal. 相似文献
145.
A field-effect transistor has been fabricated from polymer materials by printing techniques. The device characteristics, which show high current output, are insensitive to mechanical treatments such as bending or twisting. This all-organic flexible device, realized with mild techniques, opens the way for large-area, low-cost plastic electronics. 相似文献
146.
A new zinc supply parameter taking into account the intensity, quantity and buffering capacity and also the relative competitive influence of Cu2+, Fe2+, Mn2+ on the availability of Zn2+ has been tested. The proposed parameter correlated significantly and positively to Bray's per cent yield and zinc concentration in some parts of rice plant. The critical limit of soil zinc, in terms of this parameter at 15° and 30°C for rice, were 0.51 and 0.97 respectively. The required zinc addition to the deficient soil was also calculated on the basis of the values of this parameter at 30°C. 相似文献
147.
Groundwaters contaminated with excess fluoride (above 1.5 mg/L) posed some risks to the public health in India. Methods available for fluoride contaminated water treatment are cogaulation–filtration using alum + lime + bleaching powder (Nalgonda technique) and adsorption using activated alumina. Use of aluminium compounds for water treatment purpose needs replacement on neurological health problem. Objective to this, the synthesis and fluoride adsorption behavior of hydrous ferric oxide (HFO) are reported here. It is seen that fluoride adsorption density varies as a function of pH, contact time, aging time, drying temperature and particle size of HFO. Highest adsorption density for fluoride is found to be at pH 4.0. Effects of competing anions in removing fluoride from solution were tested. Arsenite, arsenate, phosphate and sulfate show strong interfering effect at high anions to fluoride molar ratio in solution. Adsorption of fluoride on HFO follows the Freundlich isotherm and the Lagergren first-order kinetic model. It was also determined that HFO is a better adsorbent in removing fluoride from high fluoride groundwater than some other adsorbents. Regeneration of fluoride-rich HFO results showed that 1.0 M NaOH solution could be used up to a maximum of 75% regeneration. 相似文献
148.
Ghosh Uday Chand Dasgupta Manotosh Debnath Sushanta Bhat Subhas Chandra 《Water, air, and soil pollution》2003,143(1-4):245-256
The anion exchange behaviour of hydrous titanium oxide(HTO) has been exploited for the management of industrialwaste effluents contaminated with chromium(VI). Theadsorption of chromium(VI) by HTO (74.0–140.0 micron) in thepH range 0.5–8.0 has been studied. It is found that theadsorption of chromium(VI) by HTO is at a maximum in the pHrange 1.5–2.0. The interference of diverse foreign ionssuch as nitrate, chloride, sulfate, phosphate, calcium,magnesium, nickel, iron(III), barium etc. on the adsorptionof chromium(VI) by HTO at optimum pH has been investigatedby a batch-operation technique. Break-through capacity,adsorption and elution of chromium(VI) using HTO have beenstudied. It is found that HTO could be reused as anadsorbent for chromium(VI). Finally, chromium(VI) wasrecovered as insoluble chromate compound from waste effluentof Hindustan Motor Limited (HML) of Hooghly, West Bengal, India. 相似文献
149.
R. Chand C. P. Srivastava B. D. Singh S. B. Sarode 《Genetic Resources and Crop Evolution》2006,53(2):219-224
Three hundred and forty five accessions of pea of diverse origin, height, leaf types and disease reaction were screened for
rust disease severity and area under disease progress curve (AUDPC). The frequency of slow rusting types in the tall, dwarf,
early and late groups appeared comparable. Of the 345 accessions, forty-four genotypes were evaluated for disease intensity,
which was converted into AUDPC, number of pustules/leaf and pustule size. Wide range of variation was found for these traits.
The slow rusting attribute of 16 genotypes was further confirmed by testing these under unprotected (inoculated) and protected
(fungicidal spray) conditions for two successive years for disease intensity by assessing the AUDPC, seed yield/plot, and
100-seed weight. The fast rusting genotypes exhibited lower AUDPC, accompanied with increased seed yield and seed weight when
grown under the protected condition, as compared to those raised under the unprotected condition. The genotypes Pant P 11,
FC 1, HUDP 16, JPBB 3 and HUP 14 appeared as slow rusting genotypes. 相似文献
150.
Changes in microbial C, N, and P were investigated for 1 year in two soils with similar physicochemical properties but supporting different crops under subtropical conditions. One was cropped with palmarosa (Cymbopogon martinii L.) and the other with Japanese mint (Mentha arvensis L.). Both the season and the type of cropping had a significant influence on changes in the soil microbial biomass. In general, soil microbial biomass C, N, and P were highest in summer months and lowest in midwinter. Soil microbial biomass levels and microbial C:N and C:P ratios were higher and N:P ratios lower under palmarosa soil than under mint. 相似文献