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Typhoon-and pollution-driven enhancement of reactive bromine in the mid-latitude marine boundary layer

National Science Review 2024年第4期11卷 93-101页

作者： Shanshan Wang Qinyi Li Ruifeng Zhang anoop sharad m.hajan Swaleha Inamdar Nuria Benavent Sanbao Zhang Ruibin Xue Jian Zhu Chenji Jin Yan Zhang Xiao Fu Alba Badia Rafael P.Fernandez Carlos A.Cuevas Tao Wang Bin Zhou Alfonso Saiz-Lopez Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3) Department of Environmental Science and Engineering Fudan University Institute of Eco-Chongming(IEC) Department of Atmospheric Chemistry and Climate Institute of Physical Chemistry Blas CabreraCSIC Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Environment Research Institute Shandong University Centre for Climate Change Research Indian Institute of Tropical MeteorologyMinistry of Earth Sciences Department of Chemistry University of Colorado Boulder Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua University Sostenipra Research Group Institute of Environmental Science and Technology(ICTA)Universitat Autonoma de Barcelona(UAB) Institute for Interdisciplinary Science (ICB) National Research Council (CONICET)

Tropospheric reactive bromine is important for atmospheric chemistry,regional air pollution,and global *** studies have reported measurements of atmospheric reactive bromine species in different environments,and proposed their main sources,***-salt aerosol（SSA）,oceanic biogenic activity,polar snow/ice,and *** and other strong cyclonic activities（***） induce abrupt changes in different earth system processes,causing widespread destructive ***,the role of typhoons in regulating reactive bromine abundance and sources remains ***,we report field observations of bromine oxide（BrO）,a critical indicator of reactive bromine,on the Huaniao Island（HNI）in the East China Sea in July *** observed high levels of BrO below 500 m with a daytime average of9.7±4.2 pptv and a peak value of ～26 pptv under the influence of a *** field measurements,supported by model simulations,suggest that the typhoon-induced drastic increase in wind speed amplifies the emission of SSA,significantly enhancing the activation of reactive bromine from SSA *** also detected enhanced BrO mixing ratios under high NOxconditions（ppbv level） suggesting a potential pollution-induced mechanism of bromine release from *** elevated levels of atmospheric bromine noticeably increase ozone destruction by as much as ～40% across the East China *** the high frequency of cyclonic activity in the northern hemisphere,reactive bromine chemistry is expected to play a more important role than previously thought in affecting coastal air quality and atmospheric oxidation *** suggest that models need to consider the hitherto overlooked typhoon-and pollution-mediated increase in reactive bromine levels when assessing the synergic effects of cyclonic activities on the earth system.

关键词： reactive bromine atmospheric chemistry marine boundary layer atmospheric oxidation capacity marine emission

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Effect of process parameter on the flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical milling

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Particuology 2024年第9期92卷 210-223页

作者： Annadaa Shankara Dash Indranil manna Deepa Devapal sharad Chandra Sharma Jyotsna Dutta majumdar School of Nanoscience and Technology IIT KharagpurWest BengalIndia BIT mesra RanchiJharkhandIndia Department of metallurgical and materials Engineering IIT KharagpurWest BengalIndia Vikram Sarabhai Space Centre ThiruvanthapuramKeralaIndia

The present study concerns understanding the effect of process parameters on the characteristics and flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical *** milling has been conducted in a planetary ball mill with tungsten carbide(WC)ball,with ball to powder ratio of 10:1 at 300 rpm speed,using 1%stearic acid and toluene as process control agent(PCA)with time varying from 10 h to 36 *** synthesized nanocrystalline powder were characterized by Scanning Electron microscopy,X-ray Diffraction technique,X-ray Photoelectron Spectroscopy,and Differential Scanning ***,flowability in terms of Hausner ratio was assessed by Tap Density *** particle size of the powder was found to decrease from 33μm to 22μm after 10 h of milling and further increases to 43μm and 38μm after 25 and 36 h of milling,respectively,in stearic acid ***,in toluene medium particle size continuously decreases from 33μm to 9.7μm with increasing milling *** particle morphology changes from spherical to platelet shape at low milling hours in both of the *** 25 h of milling,the shape of the particles is nearly spherical for stearic acid and irregular for toluene used as a *** size was found to decrease with increasing milling time from 147 nm to 7.7 nm and to 6.4 nm in stearic acid and toluene media,*** was presence ofγ,γʹ,β,hcp-Co,Al_(2)O_(3)and AlOOH phases on the powder particles milled in both the *** measured Hausner ratio of the powders was found to vary from 1.18 to 1.32 in stearic acid medium,and was found to increase with increasing milling *** the other hand,in toluene media flowability decreases(Hausner ratio increases from 1.33 to 1.44)with increasing milling time.

关键词： mechanical milling microstructure Process control agent(PCA) CoNiCrAIY Toluene Stearic acid Flowability

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Direct-Seeded Rice: Genetic Improvement of Game-Changing Traits for Better Adaption

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Rice science 2024年第4期31卷 417-433页

作者： Priyanka NEGI Jagadish RANE Rajendra Sadashiv WAGH Tukaram Jayaram BHOR Dipti Digambar GODSE Priyanka JADHAV C.ANILKUmAR Dasari SREEKANTH K.SAmmI REDDY sharad Ramrao GADAKH K.m.BORAIH C.B.HARISHA P.S.BASAVARAJ Indian Council of Agricultural Research(ICAR)-National Institute of Abiotic Stress management Baramati 413115India mahatma Phule Krishi Vidyapeeth Rahuri 413722India ICAR-Central Institute for Arid Horticulture Bikaner 334006India ICAR-National Rice Research Institute Cuttack 753006India ICAR-Directorate of Weed Research Jabalpur 482004India Dr.Panjabrao Deshmukh Krishi Vidyapeeth Akola 444104India

The sustainability of rice production continues to be a subject of uncertainty and inquiry attributed to shifts in climatic conditions. In light of the impending climate change crisis and the high labor and water costs accompanying it, direct-seeded rice(DSR) is unquestionably one of the most practical solutions. Despite its resource and climate-friendly advantages, early maturing rice faces weed competitiveness and seedling establishment challenges. Resolving these issues is crucial for promoting its wider adoption among farmers, presenting it as a more effective sustainable rice cultivation method globally. Diverse traditional and contemporary breeding methods are employed to mitigate the limitations of the DSR approach, leveraging advanced techniques such as speed breeding and genome editing. Focusing on key traits like mesocotyl length elongation, early seedling vigor, root system architecture, and weed competitiveness holds promise for transformative improvements in DSR adaptation at a broader scale within farming communities. This review aims to summarize how these features contribute to increased crop production in DSR conditions and explore the research efforts focusing on enhancing DSR adaptation through these traits. Emphasizing the pivotal role of these game-changing traits in DSR adaptation, our analysis sheds light on their potential transformative impact and offers valuable insights for advancing DSR practices.

关键词： climate change direct-seeded rice aerobic rice early vigor trait

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Field investigation of carbon dioxide(CO_(2))fluxes and organic carbon from a conserved paddy field of North-East India

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International Soil and Water Conservation Research 2017年第4期5卷 325-334页

作者： Jayashree Dutta sharad Gokhale Department of Civil Engineering Indian Institute of Technology GuwahatiGuwahati-781039India

This study investigates the effects of conserved tills on the fluxes of carbon dioxide(CO_(2))and soil organic carbon(SOC)from a rain-fed-paddy plot in Assam(North-eastern state of India).Two paddy plots identical in soil properties,developed to cultivate rice(Sali,grown in low-lying areas of Assam),were adjacent to each other to follow a conventional agricultural practice in one and conservation in the *** chambers(1 m×0.6 m×0.4 m)were placed in both the plots to collect runoff for analyzing CO_(2) *** results of the both practices have been *** conservation plot,the SOC was high in the range from 3.17+0.01 kg m^(−2) to 20.42+0.56 kg m^(−2) and the CO_(2) emission was less,i.e.97.30+7.11 mg m^(−2) h^(-1) as compared to 189.65+4.37 mg m^(−2) h^(-1) of the conventional *** tillage practiced for the conservation plot facilitated higher porosity(50.11+8.40%to 88.87+3.59%)and greater water retention(47.47+1.15%to 101.37+1.63%)in the *** results indicate that more tillage exposed the soil to atmospheric oxygen more,which leads to excess mineralization of organic carbon and emissions of CO_(2) as in the conventional plot.

关键词： Paddy SOC CO_(2) Emission Tillage

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Using machine learning to predict habitat suitability of sloth bears at multiple spatial scales

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Ecological Processes 2021年第1期10卷 634-645页

作者： Tahir Ali Rather sharad Kumar Jamal Ahmad Khan Department of Wildlife Sciences Aligarh Muslim UniversityAligarhUttar Pradesh 202002India The Corbett Foundation 81-88Atlanta BuildingNariman PointMumbaiMaharashtra 400021India

Background:Habitat resources occur across the range of spatial scales in the *** environmental resources are characterized by upper and lower limits,which define organisms’distribution in their *** respond to these resources at the optimal spatial ***,multi-scale assessments are critical to identifying the correct spatial scale at which habitat resources are most influential in determining the specieshabitat *** study used a machine learning algorithm random forest(RF),to evaluate the scaledependent habitat selection of sloth bears(melursus ursinus)in and around Bandhavgarh Tiger Reserve,madhya Pradesh,***:We used 155 spatially rarified occurrences out of 248 occurrence records of sloth bears obtained from camera trap captures(n=36)and scats located(n=212)in the *** calculated focal statistics for 13 habitat variables across ten spatial scales surrounding each presence-absence record of sloth ***(>5000 m)and small(1000–2000 m)spatial scales were the most dominant scales at which sloth bears perceived the habitat *** the habitat covariates,farmlands and degraded forests were the essential patches associated with sloth bear occurrences,followed by sal and dry deciduous *** final habitat suitability model was highly accurate and had a very low out-of-bag(OOB)error *** high accuracy rate was also obtained using alternate validation ***:Human-dominated landscapes are characterized by expanding human populations,changing landuse patterns,and increasing habitat *** and degraded habitats constitute~40%of the landform in the buffer zone of the *** of the management implications may be identifying the highly suitable bear habitats in human-modified landscapes and integrating them with the existing conservation landscapes.

关键词： Bandhavgarh melursus ursinus multi-scale Habitat selection Random forest Sloth bear Species distribution models

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multi-scale habitat selection and impacts of climate change on the distribution of four sympatric meso-carnivores using random forest algorithm

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Ecological Processes 2020年第1期9卷 709-725页

Background:The habitat resources are structured across different spatial scales in the environment,and thus animals perceive and select habitat resources at different spatial *** to adopt the scale-dependent framework in species habitat relationships may lead to biased ***-scale species distribution models(SDms)can thus improve the predictive ability as compared to single-scale *** study outlines the importance of multi-scale modeling in assessing the species habitat relationships and may provide a methodological framework using a robust algorithm to model and predict habitat suitability maps(HSms)for similar multi-species and multi-scale ***:We used a supervised machine learning algorithm,random forest(RF),to assess the habitat relationships of Asiatic wildcat(Felis lybica ornata),jungle cat(Felis chaus),Indian fox(Vulpes bengalensis),and golden-jackal(Canis aureus)at ten spatial scales(500-5000 m)in human-dominated *** calculated out-of-bag(OOB)error rates of each predictor variable across ten scales to select the most influential spatial scale *** scale optimization(OOB rates)indicated that model performance was associated with variables at multiple spatial *** species occurrence tended to be related strongest to predictor variables at broader scales(5000 m).multivariate RF models indicated landscape composition to be strong predictors of the Asiatic wildcat,jungle cat,and Indian fox *** the same time,topographic and climatic variables were the most important predictors determining the golden jackal *** models predicted range expansion in all four species under future climatic ***:Our results highlight the importance of using multiscale distribution models when predicting the distribution and species habitat *** wide adaptability of meso-carnivores allows them to persist in human-dominated regions and may even thrive in disturbed habi

关键词： multiple-scale multi-species Sympatric carnivores Species distribution modeling Bandhavgarh Climate change

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Role of ions and ion channels in capacitation and acrosome reaction of spermatozoa

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Asian Journal of Andrology 1999年第3期1卷 95-107页

作者： sharad B Purohit malini Laloraya G.Pradeep Kumar School of Life Sciences Devi Ahilya University Vigyan Bhavan Khandwa Road Indore 452001 M. P. India.School of Life Sciences Devi Ahilya University Vigyan Bhavan Khandwa Road Indore 452001 M. P. India.School of Life Sciences Devi Ahilya University Vigyan Bhavan Khandwa Road Indore 452001 M. P. India.

Capacitation and acrosome reaction are important prerequisites of the fertilization process. Capacitation is a highlycomplex phenomenon occurring in the female genital tract, rendering the spermatozoa capable of binding and fusionwith the oocyte. During capacitation various biochemical and biophysical changes occur in the spermatozoa and thespermatozoal membranes. Ions and ion channels also play important roles in governing the process of capacitation bychanging the fluxes of different ions which in turn controls various characteristics of capacitated spermatozoa. Alongwith the mobilization of ions the generation of free radicals and efflux of cholesterol also plays an important role in thecapacitation state of the spermatozoa. The generation of free radical and efflux of cholesterol change the mechano-dynamic properties of the membrane by oxidation of the polyunsaturated lipids and by generating the cholesterol freepatches. The process of capacitation renders the spermatozoa responsive to the inducers of the acrosome reaction. Theglycoprotein zona pellucida 3 (ZP3) of the egg coat zona pellucida is the potent physiological stimulator of the acro-some reaction; progesterone, a major compoent of the follicular fluid, is also an induce of the acrosome *** inducers of the acrosome reaction cause the activation of the various ion-channels leading to high influxes of calci-um, sodium and bicarbonate. The efflux of cholesterol during the process of capacitation alters the permeablity of themembrane to the ions and generate areas which are prone to fusion and vesculation process during the acrosome reac-tion. Ths review focuses mainly on effects of the ion and ion-channels, free radicals, and membrane fluidity changesduring the process of capacitation and acrosome reaction. (Asian J Androl 1999 Sep; 1: 95-107)

关键词： spermatozoa capacitation acrosome reaction ion channels free radicals membrane fluidity

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Bianchi Type-V Cosmological model with Linear Equation of State in Brans-Dicke Theory of Gravitation

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International Journal of Astronomy and Astrophysics 2014年第3期4卷 429-436页

作者： sharad Kandalkar Seema Samdurkar Department of mathematics Govt. Vidarbha Institute of Science & Humanities Amravati (M.S.) India

A Bianchi type-V space time is considered with linear equation of state in the scalar tensor theory of gravitation proposed by Brans and Dicke. We use the assumption of constant deceleration parameter and power law relation between scalar field øand scale factor R to find the solutions. Some physical and kinematical properties of the model are also discussed.

关键词： Bianchi Type-V model Brans-Dicke Theory Linear Equation of State

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自由取向炭/炭复合材料的新型制备及工艺优化（英文）

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新型炭材料 2018年第5期33卷 424-433页

作者： Thakur Sudesh Kumar Raunija Rajeev K.Gautam sharad Chandra Sharma Anil Verma Carbon and Ceramics Laboratory Materials and Mechanical EntityVikram Sarabhai Space Centre Indian Space Research OrganisationThiruvananthapuram 695022KeralaIndia Sustainable Environergy Research Lab(SERL) Department of Chemical Engineering Indian Institute of Technology DelhiHauz-KhasNew Delhi 110016India materials and metallurgy Group Materials and Mechanical EntityVikram Sarabhai Space Centre Indian Space Research OrganisationThiruvananthapuram 695022KeralaIndia

采用在炭纤维束的内部浸润熔融沥青的传统方法制备得到的炭/炭(C/C)复合材料难以实现细旦化水平,这是因为单束丝中含有数千根丝,经浸渍后沥青附着,从而引起沥青局部渗出,以及因不均匀沥青稳定性而导致微观结构不均匀。本文通过稳定的中... 详细信息

采用在炭纤维束的内部浸润熔融沥青的传统方法制备得到的炭/炭(C/C)复合材料难以实现细旦化水平,这是因为单束丝中含有数千根丝,经浸渍后沥青附着,从而引起沥青局部渗出,以及因不均匀沥青稳定性而导致微观结构不均匀。本文通过稳定的中间相沥青和分散的短切炭纤维混合、热压和炭化过程制备出细旦化水平的C/C复合材料。探讨了工艺参数对中间相沥青残炭率的影响。通过残炭率/工艺时间、残炭率!(表观密度/实密度)来优化工艺参数。结果表明,通过此法得到了细旦化水平的中间相沥青与炭纤维复合材料。中间相沥青的残炭率随加热升温速率、沥青/炭纤维质量比的增加而降低;随热压压力而增加。在高压力和高质量比下,发生沥青局部渗出。通过调控得到最佳的C/C复合材料制备工艺参数为:热压压力15 mPa,升温速率0. 2℃/min及沥青/炭纤维质量比1∶1。

关键词：石油沥青中间相沥青短切炭纤维热压产率

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Bearing Capacity of Embedded Strip Footing on Geogrid-Reinforced Fly Ash

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Open Journal of Civil Engineering 2016年第2期6卷 179-187页

作者： Vidya Nitin Patil Hemant sharad Chore Department of Civil Engineering AlSSMS’s College of Engineering Pune India Department of Civil Engineering Datta Meghe College of Engineering Airoli New Mumbai India

Fly ash is a pozzolanic waste from the burning of coal ash in thermal power plant which will be unchangeable in India and increasing environmental pollution. There is an urgent need of increasing bulk utilization of fly ash in geotechnical application. In this regard, a study was undertaken to investigate the bearing capacity of fly ash slopes (β) with the strip footing of width (B) 0.1 m located at different edge distances (De = 1B, 2B, 3B) from slope crest. These tests were conducted in the laboratory and the pressure-settlement behaviour of strip footing on unreinforced and reinforced fly ash slope having an angle of 45? was studied. The embedment ratio (Z/B = 0.30), and the depth of first layer of polyester geogrid reinforcement were investigated with different footing edge distances (De = 1B, 2B, 3B). From the experiment, pressure and settlements were measured and subsequently, the pressure settlement curves were drawn. It is observed from test results that the load carrying capacity is found to increase with an edge distance in both cases: unreinforced and reinforced slope. Also, a substantial increase is observed in the bearing capacity with the addition of geogrid reinforcement. It is observed that, the bearing capacity ratio (BCR) decreases with edge distance increase. These investigations demonstrate that both, the ultimate bearing capacity and settlement characteristics of the foundation, can be improved due to the inclusion of reinforcements within the fill.

关键词： Bearing Capacity Embedment Ratio Fly Ash Geogrid

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