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Decomposition and nutrient release patterns of Phyllostachys bambusoides and Arundinaria racemosa, India

Journal of Forestry Research 2012年第2期23卷 245-252页

作者： k.Upadhyaya A.Arunachalam k.Arunachalam a.k.das Department of Forestry Mizoram UniversityAizawl-796004MizoramIndia Department of Agro-Forestry ICARPUSANew Delhi-110012India Department of Forestry North Eastern Regional Institute of Science and TechnologyNirjuli-791109India Department of Botany Rajiv Gandhi UniversityRono HillsDoimukhItanagar-791111India

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.

关键词： decomposition decay constant nutrient release mineraliza-tion immobilization bamboo

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Tropical cyclone track and intensity prediction skill of GFS model over NIO during 2019&2020

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Tropical Cyclone Research and Review 2022年第1期11卷 36-49页

作者： Ch.Sridevi D.R.Pattanaik a.k.das Akhil Srivastava V.R.Durai C.J.Johny Medha Deshpande P.Suneetha Radhika kanase India Meteorological Department Numerical Weather Prediction DivisionLodhi RoadNew Delhi110003India Indian Institute of Tropical Meteorology MoESPune411008India Dept of Meteorology and Oceanography Andhra UniversityVisakhapatnamAndhra Pradesh530003India

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 *** 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 *** is one of the operational models in the India Meteorological Department(IMD),which provides the medium-range weather forecast up to 10 *** 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 *** 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 *** positive ATE(76–332 km)indicates the predicted track movement is faster than the observed track during both *** positive CTE values for most forecast lead times suggest that the predicted track is towards the right side of the observed track during both *** 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 ***,most of the time model under-predicted the cyclone intensity during both ***,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.

关键词： Tropical cyclone Track prediction GFS NWP Global model GFDL

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Optical Emission Spectroscopic Study During the Evaporation of Aluminium in the Thermal Plasma Reactor

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Plasma Science and Technology 2010年第1期12卷 27-30页

作者： I.BANERJEE N.V.kULkARNI S.kARMAkER V.L.MATHE S.V.BHORASkAR a.k.das Applied Physics Department Birla Institute of Technology Department of Physics University of Pune Department Bhabha Atomic Research Center

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.

关键词： thermal plasma reactor aluminium oxidation optical emission spectroscopy,X-ray diffraction

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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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地质地球化学 1990年第3期18卷 62-63,F004页

作者： N.k.Roy a.k.das 米瑞华南开大学测试计算中心

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-... 详细信息

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。

关键词：原子吸收法岩石硫化物锑

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Commentary on“Incidence of urinary incontinence following endoscopic laser enucleation of the prostate by en-bloc and non-en-bloc techniques:a multicenter,real-world experience of 5068 patients”

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Asian Journal of Andrology 2024年第3期26卷 333-334页

作者： James F Jiang Narmina k Onder Akhil k das Department of Urology University of California Irvine Orange CA 92868 USA.

Laser enucleation of the prostate is a proven and effectivesize-independent method for the surgical management of symptomaticbenign prostatic hyperplasia(BPH)and is considered as the“goldstandard”by many *** major hurdles that stand in theway of this becoming a universally used procedure for BPH are thesteep learning curve associated with mastering the procedure andpossibility of perioperative transient *** advances inteaching methodologies have helped tackle the difficulty in learning itand increased the number of urologists utilizing the *** forthe second hurdle,transient incontinence rates postlaser enucleationof the prostate have improved with the advent of newer techniques *** et al.1 assesses the incidence of stress,urge,andmixed urinary incontinence following laser enucleation of the prostateby comparing en-bloc and non-en-bloc techniques in a multicenterseries of 5068 men with BPH.

关键词： urinary incontinence transient

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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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内蒙古林业科技 1989年第2期15卷 47-52页

作者： a.k.das P.S.Ramakrishnan 李爱平内蒙古林科院

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... 详细信息

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。

关键词：卡西亚松地生物量养分含量

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Effect of eccentric and inclined loading on the bearing capacity of strip footing placed on rock mass

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Journal of Mountain Science 2024年第1期21卷 292-312页

作者： Shuvankar das Debarghya CHAkRABORTY Department of Civil Engineering Indian Institute of Technology KharagpurWest Bengal-721302India

This paper deals with the bearing capacity determination of strip footing on a rock mass in hilly area by considering the influence of inclined and eccentric loading. Applying the generalized HoekBrown failure criterion, the failure behavior of the rock mass is modeled with the help of the power cone programming in the lower bound finite element limit analysis framework. Using bearing capacity factor(Ns), the change in bearing capacity of the strip footing due to the occurrence of eccentrically inclined loading is presented. The variations of the magnitude of Ns are obtained by examining the effects of the Hoek-Brown rock mass strength parameters(uniaxial compressive strength(sci), disturbance factor(D), rock parameter(mi), and Geological Strength Index(GSI)) in the presence of different magnitudes of eccentricity(e) and inclination angle(λ) with respect to the vertical plane, and presented as design charts. Both the inclined loading modes, i.e., inclination towards the center of strip footing(+λ) and inclination away from the center of strip footing(-λ), are adopted to perform the investigation. In addition, the correlation between the input parameters and the corresponding output is developed by utilizing the artificial neural network(ANN). Additionally, from sensitivity analysis, it is observed that inclination angle(λ) is the most sensitive parameter. For practicing engineers, the obtained design equation and design charts can be beneficial to understand the bearing capacity variation in the existence of eccentrically inclined loading in mountain areas.

关键词： Eccentric and inclined Power cone programming Rock mass Limit analysis Artificial neural network

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Boulder-induced form roughness and skin shear stresses in a gravel-bed stream

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Journal of Mountain Science 2024年第1期21卷 346-360页

作者： das Ratul DATTA Akash Civil Engineering Department National Institute of Technology AgartalaAgartala-799046India

Boulder spacing in mountain rivers and near-wake flow zones within the boulder array is very useful for fish habitat and growth of aquatic *** present study aims to investigate how the boulder array and spacing influence the near-bed flow structures in a gravel-bed *** are staggered over a gravel-bed stream with three different inter-boulder spacing namely(a)large(b)medium and(c)small *** acoustic Doppler velocimeter was used for flow measurements in a rectangular channel and the results were compared with those acquired from numerical *** time-averaged velocity profiles at the near-wake flow zones of boulders experience maximum flow retardation which is an outcome of the boulder-induced form *** ratio of velocity differences associated to form and skin roughness and its positive magnitude reveals the dominance of form roughness closest to the *** roughness computed is 1.75 to 2 times higher than the skin roughness at the near-wake flow *** particular,the collective immobile boulders placed at different inter-boulder spacings developed high and low bed shear stresses closest to the *** low bed shear stresses characterised by a secondary peak developed at the trough location of the boulders is attributed to the skin shear ***,the spatial averaging of time-averaged flow quantities gives additional impetus to present an improved illustration of fluid shear *** formation of form-induced shear stress is estimated to be 17%to 23%of doubleaveraged Reynolds shear stress and partially compensates for the damping of time-averaged Reynolds shear stress in the interfacial *** quadrant analysis of spatial velocity fluctuations depicts that the form-induced shear stresses are dominant in the interfacial sub-layer and have no significance above the gravel-bed surface.

关键词： Array of boulders Near wake flow zones Velocity distributions Skin roughness Form induced shear stresses

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A Cocktail of Natural Compounds Holds Promise for New Immunotherapeutic Potential in Head and Neck Cancer

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Chinese Journal of Integrative Medicine 2024年第1期30卷 42-51页

作者： Sunil kumar Asmita das Department of Biotechnology Delhi Technological UniversityDelhi(110042)India

Objective: To obtain detailed understanding on the gene regulation of natural compounds in altering prognosis of head and neck squamous cell carcinomas(HNSC). Methods: Gene expression data of HNSC samples and peripheral blood mononuclear cells(PBMCs) of HNSC patients were collected from Gene Expression Omnibus(GEO). Differential gene expression analysis of GEO datasets were achieved by the GEO2R tool. Common differentially expressed gerres(DEGs) were screened by comparing DEGs of HNSC with those of PBMCs. The combination was further analyzed for regulating pathways and biological processes that were affected. Results: Totally 110 DEGs were retrieved and identified to be involved in biological processes related to tumor regulation. Then 102 natural compounds were screened for a combination such that the expressions of all 110 commonly DEGs were altered. A combination of salidroside, ginsenoside Rd, oridonin, britanin, and scutellarein was chosen. A multifaceted, multi-dimensional tumor regression was showed by altering autophagy, apoptosis, inhibiting cell proliferation, angiogenesis, metastasis and inflammatory cytokines production. Conclusions: This study has helped develop a unique combination of natural compounds that will markedly reduce the propensity of development of drug resistance in tumors and immune evasion by tumors. The result is crucial to developing a combinatorial natural therapeutic cocktail with accentuated immunotherapeutic potential.

关键词： natural compounds chemopreventive gene expression head and neck cancer immunomodulator salidroside ginsenoside Rd oridonin britanin scutellarein

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旋涡喷枪中的压降

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中国有色冶金 1989年第3期26卷 39-44页

作者： a.k.das 叶芸

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... 详细信息

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。

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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