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Decomposition and nutrient release patterns of Phyllostachys bambusoides and Arundinaria racemosa, India 被引量:2
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作者 K.Upadhyaya A.Arunachalam +1 位作者 K.Arunachalam a.k.das 《Journal of Forestry Research》 CAS CSCD 2012年第2期245-252,共8页
We investigated decomposition and nutrient release patterns of leaf and sheath litter of two important highland bamboo species (viz. Phyllostachys bambusoides Sieb. (Zucc.) and Arundinaria racemosa Munro) by using... We investigated decomposition and nutrient release patterns of leaf and sheath litter of two important highland bamboo species (viz. Phyllostachys bambusoides Sieb. (Zucc.) and Arundinaria racemosa Munro) by using a litter bag technique. Our objective was to improve understanding of the addition of organic matter and nutrients to soil from the litter of two abundant highland bamboo species, species that support the local population of the region in many ways. N concentration and N/P ratio were significantly higher (p〈0.01) in leaf litter of P bambusoides. Significantly, larger values of lignin concentration, C/N ratio, and lignin/N ratio were found in the sheath litter ofA racemosa. Weight loss of both leaf and sheath litter was strongly positively correlated with N and N/P ratio, and significantly negatively correlated 6o〈0.01) with C/N ratio. Lignin/N had a negative correlation with decay rate. In both species, only lignin concentration of the litter showed strong positive correlation with N release. Litter decomposition and N release patterns were similar for the two bamboo species, whereas, P release rate from leaf litter was higher in P bambusoides and differed significantly between sheath and leaf litter for both species. The complex pattern of nutrient release through mineralization and immobilization during litter decomposition ensures nutrient availability in both managed and natural bamboo stands subjected to anthropogenic disturbances. 展开更多
关键词 DECOMPOSITION decay constant nutrient release mineraliza-tion IMMOBILIZATION BAMBOO
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用火焰和电热原子吸收法测定岩石和硫化物矿石中的锑
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作者 N.K.Roy a.k.das 米瑞华 《地质地球化学》 CAS CSCD 北大核心 1990年第3期62-63,F004,共3页
本文论述了用火焰原子吸收法(FAA)和电热原子吸收法(ETAA)测定岩石和硫化物矿石中μg/g级的锑。FAA法需要把锑以碘化物的形式从稀盐酸溶液中萃取到含有三正辛基氧膦的甲基异丁基酮(MIBK)中,使锑与基体元素分离,然后把萃取物吸喷到空气-... 本文论述了用火焰原子吸收法(FAA)和电热原子吸收法(ETAA)测定岩石和硫化物矿石中μg/g级的锑。FAA法需要把锑以碘化物的形式从稀盐酸溶液中萃取到含有三正辛基氧膦的甲基异丁基酮(MIBK)中,使锑与基体元素分离,然后把萃取物吸喷到空气-乙炔火焰中进行测量。必要时,也可以首先让基体元素铜和铅在氨性介质中随氢氧化铁共沉淀,或者让铅变为硫酸盐与锑分离。ETAA法需要让锑与氢氧化铁共沉淀,再把沉淀溶解于稀硝酸中,与释放剂镍溶液混合,用钨丝原子化器进行ETAA测量。 展开更多
关键词 原子吸收法 岩石 硫化物
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Optical Emission Spectroscopic Study During the Evaporation of Aluminium in the Thermal Plasma Reactor
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作者 I.BANERJEE N.V.KULKARNI +3 位作者 S.KARMAKER V.L.MATHE S.V.BHORASKAR a.k.das 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第1期27-30,共4页
The oxidation of aluminium was studied using optical emission spectroscopy (OES) during the evaporation of aluminium in traces of oxygen in a thermal plasma reactor. The ratio of the measured line intensities of Al-... The oxidation of aluminium was studied using optical emission spectroscopy (OES) during the evaporation of aluminium in traces of oxygen in a thermal plasma reactor. The ratio of the measured line intensities of Al-O with that of Al follows the exact trend as of that obtained from the corresponding line intensities in X-ray diffraction spectra of the synthesized samples. In this paper the inherent capacity of emission spectroscopy in evaluating the growth processes under plasma induced reactions is presented. 展开更多
关键词 thermal plasma reactor aluminium OXIDATION optical emission spectroscopy X-ray diffraction
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不同年龄卡西亚松地上生物量及养分含量的研究
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作者 a.k.das P.S.Ramakrishnan 李爱平 《内蒙古林业科技》 北大核心 1989年第2期47-52,共6页
本文选择了1—22年生的九个林分用来研究卡西亚松(Pinus Kesiya)地上部分干物质及养分含量。研究结果表明随林龄的增长,干物质分配到树干部分的在增加,针叶部分的在减少。年平均生产力随林龄而增加。净初级生产力在5—7年生时达到最高峰... 本文选择了1—22年生的九个林分用来研究卡西亚松(Pinus Kesiya)地上部分干物质及养分含量。研究结果表明随林龄的增长,干物质分配到树干部分的在增加,针叶部分的在减少。年平均生产力随林龄而增加。净初级生产力在5—7年生时达到最高峰,以后随林龄的增长而下降。养分浓度按下列顺序递减,针叶>活枝>枯枝>树干>球果。除钙随林龄的增长而增加外,其它养分浓度随林龄的增长而减少。 展开更多
关键词 卡西亚松地 生物量 养分含量
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旋涡喷枪中的压降
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作者 a.k.das 叶芸 《中国有色冶金》 CAS 1989年第3期39-44,共6页
气流管中设置螺旋带可以改善管壁与管内气流间的传热效果,悉罗熔炼喷枪的环形空间中也装设了旋涡器,用以增强熔体和气体间的热传递,这有助于在喷枪表面形成凝固的渣层,该渣层可以保护喷枪免受腐蚀性渣的侵蚀。但是,增设旋涡器必定增加... 气流管中设置螺旋带可以改善管壁与管内气流间的传热效果,悉罗熔炼喷枪的环形空间中也装设了旋涡器,用以增强熔体和气体间的热传递,这有助于在喷枪表面形成凝固的渣层,该渣层可以保护喷枪免受腐蚀性渣的侵蚀。但是,增设旋涡器必定增加管中流体的压降,因此需采用高压气体,以便提高单位温度梯度和单位压降的热传递率。已研制出一种半经验方法,适于预测各种形状旋涡器的压降,正在进行实验工作以验证数学模型,还研究了旋涡器几何形状对传热特性的影响。 展开更多
关键词 压降 传热效果 高压气体 温度梯度 环形空间 入口效应 关联式 几何形状 传递率 半经验方法
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消除FCC再生器的缺陷
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作者 a.k.das 宋忠银 《石化译文》 2001年第1期12-15,5,共5页
在FCC装置中,部分燃烧再生器的操作比完全燃烧再生器更复杂,印度石油公司在古加拉(Gujarat)炼油厂和马特胡拉(Mathura)炼油厂遇到的几个问题及其解决方法,是FCC装置采用部分燃烧方式操作时面临的共同问题。
关键词 催化裂化装置 再生器 部分燃烧再生 助燃剂
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Tropical cyclone track and intensity prediction skill of GFS model over NIO during 2019&2020
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作者 Ch.Sridevi D.R.Pattanaik +6 位作者 a.k.das Akhil Srivastava V.R.Durai C.J.Johny Medha Deshpande P.Suneetha Radhika Kanase 《Tropical Cyclone Research and Review》 2022年第1期36-49,共14页
The Tropical Cyclone(TC)track prediction using different NWP models and its verification is the critical task to provide prior knowledge about the model errors,which is beneficial for giving the model guidance-based r... The Tropical Cyclone(TC)track prediction using different NWP models and its verification is the critical task to provide prior knowledge about the model errors,which is beneficial for giving the model guidance-based real-time cyclone warning advisories.This study has attempted to verify the Global Forecast System(GFS)model forecasted tropical cyclone track and intensity over the North Indian Ocean(NIO)for the years 2019 and 2020.GFS is one of the operational models in the India Meteorological Department(IMD),which provides the medium-range weather forecast up to 10 days.The forecasted tracks from the GFS forecast are obtained using a vortex tracker developed by Geophysical Fluid Dynamics Laboratory(GFDL).A total of 13 tropical cyclones formed over the North Indian Ocean,eight during 2019 and five in 2020 have been considered in this study.The accuracy of the model predicted tracks and intensity is verified for five days forecasts(120 h)at 6-h intervals;the track errors are verified in terms of Direct Position Error(DPE),Along Track Error(ATE)and Cross-Track Error(CTE).The annual mean DPE over NIO during 2019(51–331 km)is lower than 2020(82–359 km),and the DPE is less than 150 km up to 66 h during 2019 and 48 h during 2020.The positive ATE(76–332 km)indicates the predicted track movement is faster than the observed track during both years.The positive CTE values for most forecast lead times suggest that the predicted track is towards the right side of the observed track during both years.The cyclone Intensity forecast for the maximum sustained wind speed(Max WS)and central mean sea level pressure(MSLP)are verified in terms of mean error(ME)and root mean square error(RMSE).The errors are lead time independent.However,most of the time model under-predicted the cyclone intensity during both years.Finally,there is a significant variance in track and intensity errors from the cyclone to cyclone and Bay of Bengal basin to the Arabian Sea basin. 展开更多
关键词 Tropical cyclone Track prediction GFS NWP Global model GFDL
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