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81.
This paper reports the emissions of SO2 from large coal under staged combustion without any additive. A stainless steel combustor, 2 m high and 0.3 × 0.3 m in cross section was used. Fluidizing air was supplied through a multihole distributor. An adjustable secondary air injector was used along the vertical axis of the combustor to introduce secondary air in the freeboard. From 0–40% of total air was injected in the freeboard above the bed. The experiments were carried out at fluidizing velocities of 1–2 m s-1, bed temperatures of 1103–1153 °K, 20–40% excess air, and bed particle sizes of 665 μm. Bed temperature and level of air staging had the most significant effect on SO2 emissions. 相似文献
82.
83.
Moh Tariq Amir Khan Mohd Asif Faryad Khan Taruba Ansari Mohammad Shariq 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(6):507-524
ABSTRACT This review deals with the mechanism of antagonistic action of bacterial and fungal biocontrol agents such as the production of antibiotics, siderophores, enzyme secretion, competition for nutrition, plant growth promotion by rhizosphere microorganism. The utilisation of synthetic pesticides has been the predominant control processor for diseases brought about by phytopathogenic microorganisms. Notwithstanding, their open and improper application in intensive agriculture has realised issues that have prompted ecological contamination, considerable residues in agricultural products and phytopathogen resistance. They are likewise disrupting the quantity of beneficial microorganism which is available in the soil and capable of expanding soil fertility. Along these lines, there is a need to look through the option of synthetic pesticides that are safe, environmental and monetarily feasible to confront this problem. Biocontrol agent’s utilisation is the best alternative method to control the different kinds of diseases, such as nematode infestation, fungal pathogen and bacterial pathogen. Nowadays, biocontrol agents assume a significant role in the field of agriculture. It is a financially savvy, environment-friendly and inhibits the advancement of pathogenic microorganism sustainably. This review emphasises the role of biocontrol agents against different pathogenic microorganisms and their significance potentiality to improve plant growth and enhance defence system of plants. 相似文献
84.
S. U. KHAN 《European Journal of Soil Science》1973,24(2):244-248
The adsorption of diquat (1,1′-ethylene-2,2′-bipyridylium dibromide) and paraquat (1, 1′-dimethyl-4,4′-dipyridylium dichloride) by an organo-clay complex has been investigated. Paraquat was adsorbed by the organo-clay complex in greater amounts than was diquat. Infrared studies suggest the formation of charge-transfer complexes between diquat or paraquat and the organo-clay complex. Organic matter upon interaction with clay may facilitate the adsorption of diquat and paraquat on clay minerals in soil. 相似文献
85.
阴离子对应用于红壤中的微生物量的镉毒害的影响 总被引:4,自引:0,他引:4
A laboratory incubation experiment was conducted to elucidat the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels,i.e.,O(background),5,15,30,60 and 100μg g^-1 soil in the form of either cadmium acetate or cadmium chloride. Application of cadmium as cadmium acetate markedly reduced the soil microbial biomass carbon compared to cadmium applied as cadmium chlorde at all the tested levels.Similarly,organic carbon to biomass carbon ration in the soil was markedly increased by increasing the level of the cadmium in the soil as cadmium acetate,while the change wa much smaller in the case of cadmium chloride at the same cadmium levels.The results suggested that due consideration should be given to the source of cadmium while deciding the cadmium levles in experiments. 相似文献
86.
Sabahat Sajida Khatkar Mehar S. Nadeem Asif Thomson Peter C. 《Tropical animal health and production》2020,52(5):2309-2317
Tropical Animal Health and Production - Camel is an important domestic animal that is well adapted to extremely harsh environments. Due to its multi-purpose role, the camel is gaining importance,... 相似文献
87.
88.
Amanullah Muhammad Asif Sukhdev S. Malhi Riaz A. Khattak 《Journal of plant nutrition》2013,36(12):2080-2093
ABSTRACT Phosphorus (P) fertilizer source and plant density are considered some of the most important factors affecting crop growth and yield. A field experiment was conducted to determine the impact of P source [zero-P control, DAP (diammonium phosphate), SSP (single super phosphate), and NP (nitrphos)] and plant density (D1 = 40,000, D2 = 60,000, D3 = 80,000, and D4 = 100,000 plants ha?1) on growth and yield of maize (Zea mays L cv. Azam) on a P-deficient soil (6.6 mg P kg?1) at New Developmental Agricultural Research Farm, North-West Frontier Province (NWFP) Agricultural University, Peshawar, Pakistan, during summer 2006 in wheat-maize cropping system. Physiological maturity was delayed, plant height was increased and leaf area was decreased significantly when maize was planted at highest (D4) than at lowest plant density (D1). Application of SSP resulted in earlier physiological maturity of maize than other P fertilizers. Grain and stover yield, harvest index, shelling percentage, thousand grain weight and grains ear?1 were maximized at D3 (80,000 plants ha?1) and with application of P fertilizer. Highest benefit in growth and grain yield was obtained with application of DAP to maize planted at D3. Application of DAP at D3 gave 15, 29, and 19% higher grain yield than its application at D1, D2, and D4, respectively. In conclusion, the findings suggest that growing maize at 80,000 plants ha?1 applied with DAP can maximize productivity of maize in the wheat-maize cropping system on P-deficient soils. 相似文献
89.
Muhammad Asif Naeem Shahid Hussain Muhammad Khawar Khan Shamsa Kanwal 《Archives of Agronomy and Soil Science》2013,59(1):133-145
The boron (B) sufficiency range for plant growth is narrow and its management is problematic under brackish irrigation water. This study was conducted to evaluate the B requirement of mungbean at different sodium adsorption ratios of irrigation waters (SARiw) [control, 8 and 16 (mmolc L?1)1/2]. The boron adsorption characteristics of a loamy soil were first determined in the laboratory by equilibrating 2.5 g soil with 0.01 M CaCl2 solution containing different B levels. Boron rates for a pot study were computed against different soil solution levels by fitting sorption data in a modified Freundlich model [x/m = K f (EBC)1/n ]. The maximum increase in shoot dry matter was 11.9% when B was applied at 1.29 mg kg?1 soil at control SARiw. Visual leaf B toxicity symptoms appeared at higher B rates and became severe at higher SARiw. By contrast to Ca, shoot concentrations of B and Na increased significantly with B application and SARiw. For optimum shoot growth, internal and external B requirements were 25 mg B kg?1 shoot dry matter and 0.39 mg B L?1 soil solution, respectively, at control SARiw. At higher SARiw, a lower concentration of B in plant shoots and soil solution had an inhibitory effect on plant growth. 相似文献
90.
Mohammed Abu Ali KHAN Mohammed Anwar HOSSAIN Kenji HARA Kiyoshi OSATOMI Tadashi ISHIHARA Yukinori NOZAKI 《Fisheries Science》2003,69(6):1271-1280