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991.
A strong base anion exchange resin Amberlite IRA-400 Cl? and its hybrids with Mn(OH)2 and Cu(OH)2 are used for the removal of chromium from the synthetic spent tannery bath. The recovery is examined by varying the experimental conditions, viz., resin dosage, stirring speed, and temperature. The rate of chromium removal by Amberlite IRA-400 Cl? increased almost four times when the resin dosage was increased from 0.2 to 1.0 g. Furthermore, the rate of chromium sorption almost doubled when the stirring speed was increased from 100 to 1,000 rpm, suggesting that the sorption is a diffusionally controlled process. The chromium removal capacity also increased with the rise of temperature, showing the endothermic nature of the process. The results are explained with the help of film diffusion, particle diffusion, and Lagergren pseudo-first-order kinetic models. The kinetics results of the Amberlite IRA-400 Cl? are compared with its hybrid anion exchange resins IRA-400 Mn(OH)2 and IRA-400 Cu(OH)2. It is found that the hybrid ion exchangers have greater removal ability and fast kinetics as compared to the parent exchanger.  相似文献   
992.
In the present investigation, different strains of Plant growth-promoting rhizobacteria (PGPR), namely Bacillus megaterium, Pseudomonas fluorescens and Bacillus subtilis were evaluated for their growth-promoting effects on wheat as well as on soil properties under field conditions at two different sites having sandy loam and silt loam type of soils. PGPR strains were evaluated either singly or in consortia. Amongst all the treatments, wheat inoculated with consortia was found most effective as it increased grain yield up to 53% over control in silt loam soil, whereas, corresponding effects in sandy loam soil were less pronounced as an increase of 31% was observed in corresponding treatments, respectively. Enhanced effects on soil properties were also more intense in silt loam as there was an increase of 205% organic matter as against sandy loam soil where this value was 110%.  相似文献   
993.
Soil organic carbon(SOC) and nitrogen(N) mineralization are important biogeochemical processes associated with soil fertility. These processes are influenced by physically, chemically, and biologically stabilized SOC fractions, the mechanisms of which are not well known. The present study was conducted to evaluate the combined effect of manure and mineral fertilizers on the contents of SOC fractions to promote the mineralization of SOC and N.Treatments included: i) no fertilizer control(CK); ii)...  相似文献   
994.
A study was conducted under greenhouse conditions on wheat to investigate the utilization of dissolved organic nitrogen (N) in comparison with conventionally applied inorganic N sources (INS). Nitrogen was applied at a rate of 90 kg N ha?1 in an inorganic form, an organic high molecular weight (MW) form (casein, haemoglobin, albumin), and an organic low MW amino acid form (glycine, alanine, valine). Inorganic N sources recorded the maximum response (126% to 150%) in total dry matter (DM) production while dissolved organic nitrogen (DON) sources showed 61% to 116% increase in comparison to the control treatment. Glycine gave the maximum DM production, which was comparable with both INS treatments. In hydroponics, greater utilization occurred and the shoots had a higher N content in comparison to those grown in soil. The concentration of DON and NO3? in soil after wheat harvest was similar in all the treatments.  相似文献   
995.
Depth distribution of soil organic carbon (SOC) fractions depends on the efficiency of agro‐technical managements. Information on depth distribution of SOC fractions mostly confined to the plow layer and scant in dry lands of Punjab, Pakistan. Therefore, a field experiment was laid out with moldboard plow (MP) (control), tine cultivator (TC), and minimum tillage (MT) as main plots, and cropping sequences fallow wheat (Triticum aestivum L.), (FW, control), mungbean (Vigna radiata L.) wheat (MW), sorghum (Sorghum bicolor L.) wheat (SW), green manure wheat (GW), and mungbean‐chickpea (MC) (Cicer arietinum L.) as sub‐plots. Treatment effects were assessed for microbial biomass carbon (MBC), potentially mineralizeable carbon (PMC), particulate organic carbon (POC), dissolved organic carbon (DOC), HCl insoluble carbon (HIC), and stratification ratio (SR) in Rawal series: Udic Haplustalf. Alfisols. The MBC concentration was the highest in MT system, at 15 to 30‐cm depth under MW and PMC concentration was highest under SW with MT at 45–60 cm. MP had higher POC in FW sequence. The highest DOC was at 0 to 15‐cm depth under MC with TC and stock of HIC was more under TC with FW sequence. The highest SR of PMC was under MT with FW at 0–15:15–30 and POC was under TC and MP with FW at depths of 0–15:45–60 cm. The highest SR for DOC was under MP with GW at 0–15:45–60 cm and HCl insoluble C was under MT with SW at 0–15:45–60. In broad‐spectrum, labile organic fractions revealed differential sensitivity, and POC stocks are also a sensitive indicator to detect the short‐management effects. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
996.
A 92 d greenhouse pot experiment with maize (Zea mays L.) was carried out with a strongly saline soil from Pakistan (P‐s) in comparison with a nonsaline soil from Germany (G‐s) similar in pH and texture. The aim was to evaluate salinity effects on the decomposition of compost and effects of compost and P amendments on (1) plant growth and (2) microbial‐biomass formation. The yield of maize shoot‐C and root‐C increased in both soils in the order nonamended control < +triple superphosphate (TSP) (A1) < +compost (A2) < +(compost + TSP) (A3) < +TSP‐enriched compost (A4). In comparison with the control, the highest yield in treatment A4 was nearly doubled on the G‐s, but was increased more than 8‐fold on the saline P‐s. Averaging the three compost treatments, 32% of the compost added was decomposed in the German soil and 36% in the Pakistani soil on the basis of the compost recovered as particulate organic matter. These data were roughly in agreement with the CO2‐evolution data. This indicates that the decomposition of compost was not affected by salinity. Compost‐derived CO2 was mainly evolved until day 32, the root‐derived CO2 from day 74 until the end of the experiment. The addition of compost resulted in higher contents of microbial biomass C and biomass P, but also in that of NaHCO3‐extractable P. These three properties were significantly interrelated (r = 0.64–0.85), but on a lower level of significance than the relationships between shoot‐C, root‐C, and NaHCO3‐extractable P (r = 0.90–0.93). Applying compost enriched with TSP (incubation of compost and TSP for 24 h) provided considerably more P to plants and microorganisms than the separate addition of these two components. The results suggest that the role of the microbial biomass as a sink and source for available P deserves further attention.  相似文献   
997.
An investigation was conducted to determine the trace- mineral concentrations of forages in relation to requirements of ruminants grazing in natural pastures in the province of Punjab, Pakistan during two different seasons. Animals were closely followed during grazing and forages corresponding to those consumed by the animals were taken and analyzed for copper (Cu), iron (Fe), zinc (Zn), manganese (Mn), and cobalt (Co) concentrations. The data on the trace- mineral concentrations showed that most of these minerals varied greatly as a function of seasons and sampling periods. The forage Cu, Fe, and Zn concentrations were affected by seasonal changes but no influence of season was observed on the concentrations of forage Mn and Co concentration. Forage Zn and Co, during both seasons and at some sampling intervals, and forage Mn during summer were at marginal deficient levels, and in contrast, all other forage trace-minerals were within the required range for ruminants during both seasons. Based on these results, the supplementation of Zn, Co, and Mn would seem most important to support optimum livestock productivity.  相似文献   
998.
Protein isolates extracted from differently stabilized rice bran were analyzed to work out the food use potential. Bulk density remained higher for isolates obtained from heat stabilized bran, the treatments were found to have positive impact on the oil absorption properties, while the water absorption was slightly impaired owing to some possible configurational changes. Surface hydrophobicity and emulsion properties were improved with bran stabilization. Isolates exhibited better foaming properties owing to the flexible nature of protein molecules, with less intensive disulfide bonding, that were slightly affected by the stabilization treatment. Nitrogen solubility index followed a curved pattern with the least value near isoelectric point that showed an increasing trend toward basic pH, and parboiled protein isolates exhibited better gelling properties among the isolates.  相似文献   
999.
A field experiment was conducted in continuity of our previous study to assess the effect of Rhizobium inoculation (RI) and phosphorus fertilization (P) on growth, yield, nodulation, and P use efficiency of soybean. Different treatments were i) Rhizobium strains (0, S377, S379, and the mixture of S377+S379 i.e. S0, S1, S2, S3); ii) phosphorus fertilizer (0, 50, 100 kg ha?1 i.e. P0, P1, P2). Soybean variety NARC-1 was as used as a testing crop. Results indicated that root and shoot growth increased by RI treatments whether used alone or in combination with P. Rhizobium inoculation increased plant height up to 12% while P did not show significant effect. Increases in soot dry weight, root length and root dry weight due to RI and P was 57 and 22%, 42 and 7%, 55 and 25%, respectively, over the control treatment. Number of nodules increased from 73 in the control to a maximum of 151 in S2 while the number increased from 90 in the control to 147 in P2. Combine application of strains and P increased nodules number from 65 at S0P0 to a maximum of 183 at S2P2. Similar response was also observed for nodules mass. Soybean seed yields ranged between 1710 and 2335 kg ha?1 against 1635 kg ha?1 in the control indicating a maximum of 43% increase over control. Concentration of N and P in plants and their uptake was significantly increased by RI and P. RI also increased the N and protein content of soybean seed. Apparent recovery efficiency (ARE) of applied P was 10?12% and the agronomic, agrophysiological, recovery, utilization efficiencies, and harvest index of P decreased with increasing P rates. Nodule number significantly correlated with the DM yield (r2 = 0.78) and seed yield (r2 = 0.63) while P uptake significantly correlated with root length (r2 = 0.48) and root mass i.e. dry weight (r2 = 0.65). Also a significant correlation existed between N uptake and DM yield (r2 = 0.98) and N uptake and seed yield (r2 = 0.65), P uptake and DM yield (r2 = 0.73), and P uptake and seed yield (r2 = 0.83). The results of present study indicated a substantial growth and yield potential of soybean under the hilly region and increase in yield and N2 fixing potential (nodulation) can be achieved by applying Rhizobium inoculation with P fertilization.  相似文献   
1000.
Fang R  Feng H  Hu M  Khan MK  Wang L  Zhou Y  Zhao J 《Veterinary parasitology》2012,187(1-2):140-146
The aim of this study was to evaluate the immune responses of a SAG1 and MIC3 vaccine cocktail in BALB/c mice. Ninety-six BALB/c mice were randomly divided into eight groups, including three plasmid DNA vaccine groups (pcDNA-MIC3, pcDNA-SAG1, pcDNA-MIC3+pcDNA-SAG1), three recombinant pseudotype baculovirus vaccine groups (BV-G-MIC3, BV-G-SAG1, BV-G-SAG1+BV-G-MIC3) and two control groups (PBS and BV-G-EGFP). All groups were immunized intramuscularly twice at three-week intervals. The production of anti-Toxoplasma gondii lysate antigen (TLA) antibodies, lymphoproliferation, levels of IFN-γ, IL-4 and IL-10 and the survival time were monitored after vaccination. The results showed that immunization of BALB/c mice with MIC3 and SAG1 vaccines stimulated both the cellular and humoral immune responses with the production of anti-T. gondii TLA antibodies. The vaccine cocktails of pcDNA-MIC3+pcDNA-SAG1 or BV-G-SAG1+BV-G-MIC3 induced significantly higher immunogenicity than a single-gene vaccine (P<0.05). Splenocytes from the immunized mice significantly proliferated in response to the TLA and released interferon (IFN)-γ (P<0.05). However, the levels of IL-4 and IL-10 in the sera of the immunized mice were not significantly different from those of the controls (P>0.05). Immunization with the vaccine cocktail (BV-G-SAG1+BV-G-MIC3) in mice significantly prolonged survival (50%; P<0.05) against a lethal challenge of T. gondii (RH tachyzoites), while all mice in the other immunized groups and control groups died within 20 and 4 days post-infection, respectively. Furthermore, the recombinant pseudotype baculovirus vaccines induced better immunogenicity than the plasmid DNA vaccines (P<0.05). These results suggest that an excellent vector-mediated vaccine cocktail strategy might be used to develop a new generation of vaccines against T. gondii infection.  相似文献   
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