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91.
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
92.
Souparno Ghosh Kai Zhu Alan E. Gelfand James S. Clark 《Journal of Agricultural, Biological & Environmental Statistics》2016,21(1):111-130
Typical ecological gradient analysis for plant species considers variation in the response along a gradient of covariate values, for example, temperature or precipitation. Response is customarily modeled through the presence/absence or a suitable measure of abundance or both. Such analysis enables the creation of a climate niche or range limits for the species using this covariate. Interest often extends to two climate covariates, thus seeking a climate niche in two-dimensional space. It also seeks to learn whether the niche changes over life stages of the species. For instance, is the niche for juveniles different from that for adults? Across the climate domain, where are seedlings relatively more or less abundant than adults? Adult abundance is measured through basal area, juvenile abundance through seedling counts. Our contribution is to describe a coherent modeling approach to address the foregoing objectives. We construct a hierarchical stochastic specification that jointly models juveniles and adults with regard to their two-dimensional climate niches. Joint modeling of the abundance response surfaces is proposed because seedlings and adults are living jointly, competitively and is justified through exploratory analysis. Joint modeling can be challenging when one response is counts and the other is area. We model adult abundance and then juvenile abundance driven by adult abundance. Due to excess zeroes over our study plots, we employ zero-inflated models for both adult and seedling abundance. We demonstrate the benefits of the joint modeling through out-of-sample predictive performance. Our abundance data come from the USDA Forest Service’s Forest Inventory and Analysis dataset. Our climate data come from the 800 m resolution Parameter-elevation Regressions on Independent Slopes Model dataset. In order to extract a response to climate, we aggregate FIA plots to ecological subsections. At plot scale, micro-scale covariates explain variation in abundance; at a larger spatial scale, climate covariates can explain variation in abundance. 相似文献
93.
M. Mohanty K.K. Bandyopadhyay D.K. Painuli P.K. Ghosh A.K. Misra K.M. Hati 《Soil & Tillage Research》2007,93(2):420-428
In Vertisols of central India erratic rainfall and prevalence of drought during crop growth, low infiltration rates and the consequent ponding of water at the surface during the critical growth stages are suggested as possible reasons responsible for poor yields (<1 t ha−1) of soybean (Glycine max (L.) Merr.). Ameliorative tillage practices particularly deep tillage (subsoiling with chisel plough) can improve the water storage of soil by facilitating infiltration, which may help in minimizing water stress in this type of soil. In a 3-year field experiment (2000–2002) carried out in a Vertisol during wet seasons at Bhopal, Madhya Pradesh, India, we determined infiltration rate, root length and mass densities, water use efficiency and productivity of rainfed soybean under three tillage treatments consisting of conventional tillage (two tillage by sweep cultivator for topsoil tillage) (S1), conventional tillage + subsoiling in alternate years using chisel plough (S2), and conventional tillage + subsoiling in every year (S3) as main plot. The subplot consisted of three nutrient treatments, viz., 0% NPK (N0), 100% NPK (N1) and 100% NPK + farmyard manure (FYM) at 4 t ha−1 (N2). S3 registered a significantly lower soil penetration resistance by 22%, 28% and 20%, respectively, at the 17.5, 24.5 and 31.5 cm depths over S1 and the corresponding decrease over S2 were 17%, 19% and 13%, respectively. Bulk density after 15 days of tillage operation was significantly low in subsurface (15–30 cm depth) in S3 (1.39 mg m−3) followed by S2 (1.41 mg m−3) and S1 (1.58 mg m−3). Root length density (RLD) and root mass density (RMD) of soybean at 0–15 cm soil depth were greater following subsoiling in every year. S3 recorded significantly greater RLD (1.04 cm cm−3) over S2 (0.92 cm cm−3) and S1 (0.65 cm cm−3) at 15–30 cm depth under this study. The basic infiltration rate was greater after subsoiling in every year (5.65 cm h−1) in relation to conventional tillage (1.84 cm h−1). Similar trend was also observed in water storage characteristics (0–90 cm depth) of the soil profile. The faster infiltration rate and water storage of the profile facilitated higher grain yield and enhanced water use efficiency for soybean under subsoiling than conventional tillage. S3 registered significantly higher water use efficiency (17 kg ha−1 cm−1) over S2 (16 kg ha−1 cm−1) and S1 (14 kg ha−1 cm−1). On an average subsoiling recorded 20% higher grain yield of soybean over conventional tillage but the yield did not vary significantly due to S3 and S2. Combined application of 100% NPK and 4 t farmyard manure (FYM) ha−1 in N2 resulted in a larger RLD, RMD, grain yield and water use efficiency than N1 or the control (N0). N2 registered significantly higher yield of soybean (1517 kg ha−1) over purely inorganic (N1) (1392 kg ha−1) and control (N0) (898 kg ha−1). The study indicated that in Vertisols, enhanced productivity of soybean can be achieved by subsoiling in alternate years and integrated with the use of 100% NPK (30 kg N, 26 kg P and 25 kg K) and 4 t FYM ha−1. 相似文献
94.
George Amponsah Annor Massimo Marcone Eric Bertoft Koushik Seetharaman 《Cereal Chemistry》2014,91(1):29-34
The unit chain compositions of debranched foxtail, proso, pearl, and finger millet amylopectins and their ϕ,β‐limit dextrins were analyzed by high‐performance anion‐exchange chromatography. The ϕ,β‐limit dextrins reflected amylopectin internal chain profiles. The amylopectins had average chain lengths ranging from 17.94 to 18.12. The ranges of external chain length, internal chain length, and total internal chain length of the millet amylopectins were 11.85–12.33, 4.75–5.09, and 11.64–12.28, respectively. The relative molar concentration of B‐chains in the amylopectins was close to 50% in all samples. Significant differences were, however, observed in the proportions of very short “fingerprint” B‐chains (Bfp, degree of polymerization 3–7) and the major group of short B‐chains (BSmajor): foxtail and proso millets possessed high amounts of Bfp‐chains, whereas finger and pearl millets had higher amounts of BSmajor‐chains, suggesting possible differences in the fine structure of the clusters and building blocks of the amylopectins. Millet amylopectin can be classified structurally as type 2. 相似文献
95.
Renuka N. Waduge Danusha N. Kalinga Eric Bertoft Koushik Seetharaman 《Cereal Chemistry》2014,91(6):578-586
Wheat starches isolated from seeds harvested between 7 and 49 days after anthesis (DAA) were fractionated into large (>8 μm) and small (<8 μm) granules and studied for starch structure and architecture. Starch granules at 7 DAA possessed unimodal size distribution, whereas it was bimodal at later maturity stages. The apparent amylose fraction of starch granules at early maturity (7 and 14 DAA) consisted of intermediate‐type materials, whereas starch at later maturity stages (28 and 49 DAA) contained branched amylose. Wide‐angle X‐ray scattering (WAXS) revealed a well‐developed polymorphic structure already at 7 DAA. Although the presence of a small proportion of B‐type crystallites mixed with A‐type crystallites was observed in the X‐ray diffractogram of starches at early maturation (7 and 14 DAA), it was masked by the A‐type crystallites at later maturity stages. However, the large granules had a higher proportion of B‐type crystallites and lower relative crystallinity (RC) than their small‐granule counterpart. The iodine absorption properties of the starch granules demonstrated different levels of mobility of the starch polymers at different stages of maturity and the mobility of more glucan polymers in the large granule population compared with the small granules at the same maturity stage. Iodine did not change the characteristic A‐type crystalline pattern of starch, but it increased RC. Changes in peak width at half height based on WAXS data further suggested the possible interaction of iodine with amylopectin intercluster chain segments and branch chains in formation of inclusion complexes. 相似文献
96.
Sagar Sharath V. Saini Kuldeep Sharma Anil Kumar Kumar Sachin Kumar Rinesh Fular Ashutosh Shakya Mukesh Upadhaya Deepak Nagar Gaurav C. Shanmuganath Samanta Subhamoy Kumar Suman Ghosh Srikant 《Tropical animal health and production》2020,52(2):611-618
Tropical Animal Health and Production - The isolates of Rhipicephalus microplus collected from Madhya Pradesh (MP), Punjab (PJB) and Uttar Pradesh (UP) states of India were characterized using... 相似文献
97.
Shil Bikash Lahiri Biswajit Pal Prasenjit Ghosh Amitava Biswas Pradyut Singh Yumlembam Jackie 《Aquaculture International》2022,30(4):2017-2041
Aquaculture International - Most of the adoption studies in catfish culture were restricted to feeding habits, growth rate and morphological studies, neglecting the social factors and adoption of... 相似文献
98.
Effect of probiotic on reproductive performance in female livebearing ornamental fish 总被引:1,自引:0,他引:1
A probiotic bacterial strain, Bacillus subtilis, isolated from the intestine of Cirrhinus mrigala (Hamilton), was incorporated in fish feed at four different concentrations (5 × 108 cells g−2, 5 × 107 cells g−2, 5 × 106cells g−1 and 5 × 105 cells g−1) and fed to four species of livebearing ornamental fish, Poecilia reticulata (Peters), Poecilia sphenops (Valenciennes), Xiphophorus helleri (Heckel) and Xiphophorus maculatus (Gunther) for one year duration to observe the effect of dietary probiotic supplementation on their reproductive performance. Sixty virgin females of each species were stocked separately in circular FRP tanks (350 L) and fed diets with varying levels of probiotic cells and control feed. Broodstock performance was evaluated based on gonadosomatic index (GSI), fecundity and fry production of female broodstock. The results showed that supplementation of feed with probiotics increased significantly (P<0.05) the GSI, fecundity and fry production of spawning females and length and weight of fry in all the four species of fish. The number of dead and deformed fry were also significantly lower (P<0.05) in fish fed with the probiotic feeds. The use of higher concentration of the probiont in diet did not always lead to significantly improved reproductive performance of the spawners. Collectively, this study showed that female livebearers benefit from inclusion of probiotics in diet during their reproductive stages. 相似文献
99.
Alessandra Marti Xiaoxue Qiu Tonya C. Schoenfuss Koushik Seetharaman 《Cereal Chemistry》2015,92(5):434-440
Intermediate wheatgrass (IWG) (Thinopyrum intermedium) is a perennial grass with desirable agronomic traits and positive effects on the environment. It has high fiber and protein contents, which increase the interest in using IWG for human consumption. In this study, IWG flour was blended with refined wheat at four IWG‐to‐wheat ratios (0:100, 50:50, 75:25, and 100:0). Samples were analyzed for proximate composition, microstructure features, pasting properties (Micro Visco‐Amylo‐Graph device), protein solubility, and total and accessible thiols. Gluten aggregation properties (GlutoPeak tester) and mixing profile (Farinograph‐AT device) were also evaluated. IWG flour enrichment increased the pasting temperature and decreased the peak viscosity of blended flours. IWG proteins exhibited higher solubility than wheat, with a high amount of accessible and total thiols. The GlutoPeak tester highlighted the ability of IWG proteins to aggregate and generate torque. Higher IWG flour enrichment resulted in faster gluten aggregation with lower peak torque, suggesting weakening of wheat gluten strength. Finally, the addition of IWG to refined wheat flour resulted in a decrease in dough development time and an increase in consistency, likely because of the higher levels of fiber in IWG. The 50% IWG flour enrichment represents a good compromise between nutritional improvement and maintenance of the pasting properties, protein characteristics, and gluten aggregation kinetics. 相似文献
100.