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101.
Abstract The adult mortality of Callosobruchus chinensis L. was 100% within 24 h after artificially infesting seeds pretreated with inert clay and stored for 12 months under ambient conditions. Pre‐treatment with thiram and delsan‐30 (TCMTB) were also effective in controlling the adults by impairing oviposition. The seeds maintained over 80% germination up to 12 months of storage under all the treatments. 相似文献
102.
System of rice intensification (SRI) is a water-saving agro-technique being popularized in Southern Asia including India. A particular key practice in SRI, reduced water application (no continuous flooding), needs to be more farmer-friendly for its mass adoption under traditional and non-traditional cultivation. A field experiment was conducted maintaining different water regimes throughout the crop season (vegetative as well as reproductive stages) by scheduling irrigation applications at 1, 3, or 5 days after disappearance of ponded water (DADPW), using two different plant spacings and two different varieties. With an increase in the period of water stress, tiller production was increased significantly (P ≤ 0.05) and found to be maximum under prolonged stress, i.e., 5 days after disappearance of ponded water (5 DADPW). Increased tiller production did not result in yield increments, but yield-contributing parameters (panicle weight, grain weight per panicle, filled grain percentage, and test weight) were confirmed as critical determinants of yield. Plant nutrient (NPK) uptake was reduced under stress conditions, but the translocation of phosphorus and potassium from sources to sink was increased significantly in this study. Nutrient utilization efficiency was also enhanced under mild (3 DADPW) to prolonged (5 DADPW) water stress conditions. No significant reduction in yield was recorded under mild water stress, and this resulted in increased water productivity; however, significant yield loss was observed under prolonged water stress (5 DADPW). 相似文献
103.
Vikash Babu Syed Khalid Pasha Govind Gupta C. B. Majumdar Bijan Choudhury 《Fibers and Polymers》2014,15(1):24-29
Polyacrylonitrile (PAN) is a widely used polymer in the textile industry. PAN contains cyano groups on the surface due to which it possess low hydrophilicity and limits its application. Thus, there is a need to modify the functional groups on the surface of PAN for its industrial demand to improve moisture uptake, dyeability with ionic dyes, without affecting mechanical properties. A number of strategies such as chemical treatment, plasma treatment, enzymatic treatment etc. have been applied for the surface modification of polymer but enzymatic treatment are advantageous over plasma treatment and chemical treatment. In enzymatic treatment, reaction is limited to polymer surface only, and provides milder condition with less damage to polymer. In present study, it was found that enzyme system of Amycolatopsis sp.IITR215 was effective enzyme system for modification of surface nitrile groups of polyacrylonitrile. PAN powder was treated with the cell free extract of Amycolatopsis sp.IITR215 and it was found that the nitrile metabolizing enzymes of this strain were efficiently able to transform -CN to -COOH groups present on the surfaces of PAN powder. The formation of carboxyl group was quantified by ammonia released and dye binding assay. Further, confirmation of carboxyl group on polymer was done by FTIR and XPS. This study indicates that, specific adsorption of enzyme probably plays an important role in the enzymatic surface modification of polymer. 相似文献
104.
Bhupinder Singh Sumedha Ahuja R. K. Singhal P. Venu Babu 《Water, air, and soil pollution》2014,225(1):1-8
Implication of ureolytic biocalcification process as an efficient carbon dioxide sequestration technology was evaluated with Bacillus megaterium culture growing in a closed environment system. In three experimental sets containing either 35 % v/v CO2 in headspace (set 1) or 50 mM urea in solution (set 3) or both (set 2), change in headspace CO2, soluble calcium, and pH were monitored during 8 days of incubation. In absence of urea, headspace CO2 content continued to increase in set 1 (up to 48 % v/v) without any carbonate precipitation. However, carbonate precipitation were obvious in urea containing sets (sets 2 and 3) utilizing all the added calcium (25 mM) in just 2 and 6 days, respectively. No headspace CO2 could be detected in set 2 at the end of experimental period, and analysis suggested that this was majorly (>53 %) attributed to the solubility trapping phenomenon. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis revealed that the precipitates were made up of calcite and major fraction of vaterite polymorph of CaCO3. 相似文献
105.
106.
Martin H. Mach Babu Nott Judith W. Scott Raymond F. Maddalone Nina T. Whiddon 《Water, air, and soil pollution》1996,90(1-2):269-279
As part of a recent task under the EPRI Analytical Methods Qualification Program (RP 1851), TRW has surveyed the methods available for monitoring metal species in typical utility aqueous discharge streams. Methods for determining the individual species of these metals can become important in a regulatory sense as the EPA transitions to assessment of environmental risk based on bioavailability. For example, EPA considers methyl mercury and Cr(VI) much more toxic to the aquatic environment than inorganic mercury or Cr(III). The species of a given element can also differ in their transport and bioaccumulation. Methods for speciation generally include a selective separation step followed by standard metals analysis. Speciation, therefore, is mainly derived from the separation step and not from the method of final quantitation. Examples of separation/analysis include: selective extraction followed by graphite furnace atomic absorption or ICP-MS; separation by GC followed by metals detection; chelation and/or direct separation by LC followed by UV measurement or metals detection; and ion chromatography with conductivity, UV, or metals detection. There are a number of sampling issues associated with metal species such as stabilization (maintaining oxidation state), absorption, and filtration that need to be addressed in order to obtain and maintain a representative sample for analysis. 相似文献
107.
Babu Nott K. Anthony Selby Tammy Brice Don Goldstrohm David Morris S. R. Pate Dale Smay Terry Spaulding 《Water, air, and soil pollution》1996,90(1-2):173-181
The EPRI Tailored Collaboration State-of-the-Art Cooling Water Treatment Research Program has been initiated with several electric utility participants. Started in January 1995, the program will provide O&M cost reduction through improved cooling water system reliability and operation. This effort is discussed along with the objectives and goals, the participants and project timetable. The program will provide three (3) main results to the participating utilities: cost effective optimization of cooling water treatment, production of a new Cooling Water Treatment Manual and updating of two (2) EPRI software products — SEQUIL and COOLADD. A review of the specific objectives, project timetable and results to date will be presented. 相似文献
108.
Arbuscular mycorrhizae and phosphate solubilising bacteria of the rhizosphere of the mangrove ecosystem of Great Nicobar island, India 总被引:2,自引:0,他引:2
David Kothamasi Shalini Kothamasi A. Bhattacharyya Ramesh Chander Kuhad C. R. Babu 《Biology and Fertility of Soils》2006,42(4):358-361
Mangroves form an important ecosystem of Great Nicobar, a continental island in the Bay of Bengal with luxuriant tropical
rainforests. The rhizosphere of the mangrove plants of Great Nicobar was investigated for the presence of arbuscular mycorrhizal
fungus (AMF) and phosphate solubilising bacteria (PSB). The soils of the Great Nicobar mangroves were silt–clays and were
poor in phosphate content. Five species of AMF belonging to the genus Glomus were isolated. The %AMF colonization in the mangrove plants was between 0 and 17%, and the presence of AMF in the aerenchymatous
cortex suggests that the mangrove plants may be aiding in AMF survival by providing oxygen. Two strains of phosphate solubilising
Pseudomonas aeruginosa were found in the mangrove soils of Great Nicobar. Phosphate solubilisation by the two isolated strains was almost 70% under
in vitro conditions. PSB may play a role in the mangrove ecosystems of Great Nicobar by mobilising insoluble phosphate. The
plant roots could pick up the released phosphate directly or with the aid of AMF hyphae. 相似文献
109.
U S Babu P L Wiesenfeld M Y Jenkins 《Plant foods for human nutrition (Dordrecht, Netherlands)》1999,53(2):169-174
The impact of rosemary extract on splenic mononuclear cell proliferation was determined. Weanling male Sprague-Dawley rats were fed diets containing 0, 100, 200 or 400 ppm rosemary extract or 400 ppm butylated hydroxytoluene (BHT) in combination with 10 or 20% casein enriched diets for 8 weeks. Splenic mononuclear cells were isolated from these animals and mitogenic response to Concanavalin A (Con A), Phytohemagglutinin (PHA) and lipopolysaccharide was determined. Con A and PHA-stimulated proliferation of spleen cells from rats fed 10% casein and 200 ppm rosemary extract was significantly higher than that of cells from the corresponding control animals. However, other levels of rosemary at 10% dietary casein or rosemary at any concentration fed along with 20% dietary casein had no impact on the mitogenic stimulation of splenic mononuclear cells. Thus, these results suggest that the use of rosemary might not have a generalized immunoenhancing effect, and will probably be effective in some stressed conditions, such as protein or antioxidant deficiency. 相似文献
110.
C. Kailasam R. Chandra Babu C. Vijayalakshmi S. R. Sree Rangaswamy 《Journal of Agronomy and Crop Science》1989,162(5):354-356
The pattern of grain growth in two rice cultivars was assessed in terms of total dry weight of grain from anthesis upto maturity. Rice grain development followed a sigmoidal trend. Richards' function was found to more closely fie the data on grain growth and thus could serve as a suitable mathematical model for rice grain growth analysis. 相似文献