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Biochar Application Improves the Drought Tolerance in Maize Seedlings

Phyton-International Journal of Experimental Botany 2019年第4期88卷 379-388页

作者： A.Sattar a.sher M.Ijaz M.Irfan M.Butt T.Abbas S.Hussain A.Abbas M.S.Ullah M.A.Cheema College of Agriculture Bahauddin Zakariya University Bahadur Sub-CampusLayyah31200Pakistan Department of Agronomy Faculty of Agriculture Science and Technology Bahauddin Zakariya UniversityMultan60800Pakistan Faculty of Pharmaceutical Sciences Government College UniversityFaisalabad38000Pakistan School of Science and the Environment Grenfell Campus Memorial University of NewfoundlandCorner Brook2000A2H 5G4Canada

Application of biochar to agricultural soils is mostly used to improve soil fertility.Experimental treatments were comprised of two factors:i)drought at two level,i.e.,80%and 40%water holding capacity(WHC)which was maintained on gravimetric basis ii)three levels of biochar i.e.,control,2 t ha^(-1) and 4 t ha^(-1) added to soil.Experimentation was done to examine potential of biochar application to enhance the growth attributes,water relations,photosynthetic pigments and antioxidants activities in maize(Zea mays L.)seedlings.Results of study revealed that biochar application increased the growth qualities(total seedlings biomass,dry weight of shoot and root,shoot length and root length).In addition;contents of photosynthetic pigments(chlorophyll a,b,a+b and a/b),water relation(relative water contents,turgor potential,osmotic potential and water potential)were improved significantly due to addition of biochar.Addition of 4 t ha^(-1) biochar led to significant rise activity of enzymatic antioxidant catalase(CAT),superoxide dismutase(SOD)and peroxidase(POD)in leaf of maize seedling sunder drought as well as well watered circumstances.However,biochar applied at the rate 4 t ha^(-1) improved the all the physiological and biochemical attributes in maize seedlings under drought.From the results it was concluded that biochar application is an efficient way to alleviate adverse effect of drought stress on maize.In drought prone areas,long term impacts of biochar on production of maize and properties of soil could be recommended as upcoming shove.

关键词： Antioxidants biochar drought stress water relations chlorophyll contents

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A Robust MPPT Control Based on Double Ended Forward Converter Architecture

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Computers, Materials & Continua 2022年第1期70卷 135-150页

作者： M.Usman Khan K.M.Hasan A.Faisal Murtaza H.M.Usman Hadeed a.sher University of Engineering&Technology Lahore54000Pakistan University of Central Punjab Lahore54000Pakistan Ghulam Ishaq Khan Institute of Engineering Sciences and Technology Swabi23430Pakistan

In this paper,a stand-alone photovoltaic(PV)system based on a Double Ended Forward Converter(DEFC)is presented.The proposed converter is specified for 48 V,100Wapplications as most of the equipment used in telecommunication and aircraft fall in this range.The literature has limited potential application of DEFCin PV systems.The research work deals with an in-depth study of DEFCand proposes an improvedDEFCfor PV applications with battery backup.Besides,a bi-directional dc-dc converter for the battery is integrated to track theMaximumPower Point(MPP)of the PV generator.The converter is examined under variable irradiance and load conditions,and the analytical analysis of boundary conditions are implemented.The converter’s architecture also ensures built-in I-V curve tracing for the identification of MPP of PV generator.It offers low voltage stresses across switches and avoids sinking power supply and core resetting circuits.The topology’s behavior is analyzed based onMPP achievement and maintaining output under different conditions of battery backup availability,environmental,and load conditions.The PV system architecture is designed and analyzed theoretically and verified with simulations on the PSIM software.

关键词： Photovoltaic power converter forward converter double ended forward converter bi-directional dc-dc converter MPP I-V curve tracing

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计算材料科学:一种越来越可靠的工程技术手段(例如HgCdTe合金中的缺陷)(上)

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红外 1999年第12期20卷 1-6页

作者： a.sher 高国龙美国SRI国际公司

最近几年,计算材料科学已经发展成了一种可靠的理论。这种理论不仅能够预测理想化材料及器件的性能特性,而且还能够预测应用于实际工程发展的那些材料与器件的性能特性。其代码在工作站上运行,即使现在,其速度也是非常快的,因而足以成... 详细信息

最近几年,计算材料科学已经发展成了一种可靠的理论。这种理论不仅能够预测理想化材料及器件的性能特性,而且还能够预测应用于实际工程发展的那些材料与器件的性能特性。其代码在工作站上运行,即使现在,其速度也是非常快的,因而足以成为有用的设计工具。本文将对这一快速发展的领域的现状进行评述。为了证明这些方法的效果,本文还将对随外部加工条件而变的Hg_(0.8)Cd_(0.2)Te合金的天然点缺陷、复合缺陷以及杂质密度进行预测。在已进行过测量的地方,所观测到的数值与预测值符合得很好。例如,我们发现,如果材料从现存曲线的Te侧生长,As便会明显地结合在阳离子亚晶格上(如同分子束外延生长时所发生的情况一样),而在Hg饱和的生长过程中,它往往会驻留在阴离子亚晶格上。As在亚晶格上是施主,在Te亚晶格上便是受主。为了促使As从阳离子亚晶格处向阴离子亚晶格处转移,我们发明了一种在分子束外延生长之后进行处理的方法。所提出的该方法中,已经过测试的那些方面是行得通的。

关键词：计算材料科学 HoCdTe 缺陷半导体

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计算材料科学:一种越来越可靠的工程技术手段(例如HgCdTe合金中的缺陷)(下)

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红外 2000年第1期21卷 36-39页

作者： a.sher 高国龙美国SRI国际公司

光动力疗法是一种涉及光和化学的新的医疗方法,有朝一日,这种医疗方法将成为受各种疾病如癌症和斑点退化打击的病人的救助者(斑点恶化是七十岁以上老人致盲的主要原因)。这种医疗方法采用一种光敏药物,当受到一种特定波长的光(通常为激... 详细信息

光动力疗法是一种涉及光和化学的新的医疗方法,有朝一日,这种医疗方法将成为受各种疾病如癌症和斑点退化打击的病人的救助者(斑点恶化是七十岁以上老人致盲的主要原因)。这种医疗方法采用一种光敏药物,当受到一种特定波长的光(通常为激光)照射时,它会产生一种可杀死有病细胞的活性氧。

关键词：计算材料科学 HgcdTe合金缺陷

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Phytochemical analysis, antioxidant, acetylcholinesterase, and α-amylase inhibitors from Hippeastrum hybridum extract

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Journal of Traditional Chinese Medicine 2024年第3期44卷 496-504页

作者： Naila.sher Mushtaq Ahmed Nadia Mushtaq Department of Biotechnology University of Science and Technology Department of Botany University of Science and Technology

OBJECTIVE:To investigate the effects of Hippeastrum hybridum（HH） as a free radical scavenger,and an inhibitor of the two enzymes i-e Alpha-amylase（α-amylase） and acetylcholinesterase（AChE）.METHODS:In this study,HH plant was preliminary analyzed for phytochemical screening and then tested for its antioxidant,anti-α-amylase,and anti-AChE efficiency via standard procedures.RESULTS:Phytochemical analysis shows the existence of different compounds;while Coumarins and quinones were absent.The total phenolic,flavonoid,and tannins content were found to be（78.52±0.69） mg GAE/g,（2.01±0.04） mg RUE/g,and（58.12±0.23） mg TAE/g of plant extract respectively.28.02%±0.02% alkaloid and 2.02%±0.05% saponins were present in the HH extract.The HH extract showed the anti-oxidant property with IC50（50%inhibition） of（151.01±0.13）(HH),（79.01±0.04）(Ascorbic acid) for ferric reducing,（91.48±0.13）(HH),（48.02±0.11）(Ascorbic acid) against Ammonium molybdenum,（156.02±0.31）(HH),（52.38±0.21）(Ascorbic acid) against DPPH,136.01±0.21（HH）,52.02±0.31（Ascorbic acid） against H2O2,and 154.12±0.03（HH）,（40.05±0.15）(Ascorbic acid)μg/mL against ABTS respectively.Statistical analysis indicated that HH caused a competitive type of inhibition of α-amylase(Vmaxremained constant and Km increases from 10.65 to84.37%) while Glucophage caused the un-competitive type of inhibition i-e both Km and Vmaxdecreased from40.49 to 69.15%and 38.86 to 69.61%respectively.The Ki,（inhibition constant）;KI,（dissociation constant）,Km,（Michaelis-Menten constant）,and IC50 were found to be62,364,68.1,and 38.08±0.22 for HH and 12,101.05,195,34.01±0.21 for Glucophage.Similarly,HH causes an anon-competitive type of inhibition of AChE i-e Km remains constant while Vmaxdecreases from 60.5%to74.1%.The calculated Ki,KI,Km,and IC50 were found to be 32,36.2,0.05,and 18.117±0.018.CONCLUSION:From the current results,it is concluded that HH extract contains bioactive compounds,and could be a good alternative to controlling oxidants,Alzheimer‘s and Type-Ⅱ diabetic diseases.

关键词： Hippeastrum hybridum acetylcholinesterase alpha-amylase antioxidant phytochemicals

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Influence of edaphic factors on distribution and condition of Himalayan silver birch(Betula utilis D.Don)communities in the northwestern Indian Himalayas

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Journal of Mountain Science 2024年第2期21卷 590-606页

作者： Khashti DASILA Renu RAWAL Tanay BARMAN sher Singh SAMANT Anita PANDEY Veena PANDE G.B.Pant National Institute of Himalayan Environment Almora 263643India Centre of Excellence on Sustainable Land Management Indian Council of Forestry Research and EducationDehradun 248006India Uttarakhand State Council for Science&Technology Dehradun 248015India Department of Biotechnology Graphic Era(Deemed to be University)Dehradun 248002India Department of Biotechnology Kumaun UniversityNainital 263136India

The basic concept of phytosociology is crucial for the assessment of species composition and dynamic ecological succession of forests supporting ecological services,functions,disturbance,and resilience that lead to the development of integrated areas such as ecological niche modeling and contribute to identifying the valuable bio-indicators which can be used in framing conservation and management planning.B.utilis is one of the most dominant tree species of treeline ecotone in the Himalayan Region.The species is also considered as indicator species for monitoring the past and recent climate change impact.The current study was carried out in the natural populations of B.utilis from the sub-alpine zone of North-western Indian Himalaya.The birch dominated forest harbors a total of 305 plant species comprising Angiosperms(51 families,160 genera and 277 species),Gymnosperms(03 families,05 genera and 07 species)and Pteridophytes(07 families,11 genera and 21 species)with Asteraceae,Ranunculaceae and Rosaceae as dominant family.Birch forests are found dominant in shady moist habitat and North West aspect.Geographical characteristics,anthropogenic and developmental activities affect the population structure of B.utilis and associated species.However,the species has fair regeneration status in the study area.The acidic nature of soil pH and spatial variation in edaphic characteristics may be due to geographical differences,rooting patterns and litter accumulation of below and above-ground vegetation.Biomass estimation of a representative population of B.utilis from each site showed that TAGBD,TCD and TBD were found maximum in ST3(Hamta Pass II site).The CCA analysis determined that environmental variables such as altitude,organic matter,available phosphorous,organic carbon,available nitrogen,and electrical conductivity played a significant role in determining tree species composition and distribution in B.utilis dominated forests.

关键词： Species composition Indicator species Biomass North-western Indian Himalaya Regeneration Environmental variables

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Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr M-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil M.Patange P.M.Dighe sher Singh Meena Abdullah GAl-Sehemi Mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=0.05.The hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared spectroscopy.The creation of the M-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray diffractograms.The occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> 0.The refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter ratio.The crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice sites.The XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent elements.The nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's formula.The analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) phase.The morphology of the hexaferrites was analyzed from the FESEM profiles of the ferrite samples.The magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.M,and Mossbauer spectroscopy,respectively.The hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the study.The substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity M?ssbauer spectroscopy

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Interdecadal variation of drought patterns and associated influencing factors in the north-south transitional zone of China

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Journal of Geographical Sciences 2024年第7期34卷 1253-1279页

作者： DONG Qingdong ZHU Lianqi DUAN Zheng WANG Liyuan CHEN Chaonan LI Yanhong ZHU Wenbo GURUNG sher Bahadur The College of Geography and Environmental Science Henan UniversityKaifengHenan475004China Department of Physical Geography and Ecosystem Science Lund UniversityLundS-22362Sweden Central Department of Geography Tribhuvan UniversityKathmandu44600Nepal

In the context of global warming,escalating water cycles have led to a surge in drought frequency and severity.Yet,multidecadal fluctuations in drought and their multifaceted influencing factors remain inadequately understood.This study examined the multidecadal changes in drought characteristics(frequency,duration,and severity)and their geographical focal points within China's north-south transitional zone,the Qinling-Daba Mountains(QDM),from 1960 to 2017 using the Standardized Precipitation Evapotranspiration Index(SPEI).In addition,a suite of eight scenarios,correlation analysis,and wavelet coherence were used to identify the meteorological and circulation factors that influenced drought characteristics.The results indicate the following:(1)From 1960 to 2017,the QDM experienced significant interdecadal variations in drought frequency,duration,and severity,the climate was relatively humid before the 1990s,but drought intensified thereafter.Specifically,the 1990s marked the period of the longest drought duration and greatest severity,while the years spanning 2010 to 2017 experienced the highest frequency of drought events.(2)Spatially,the Qinling Mountains,particularly the western Qinling Mountain,exhibited higher drought frequency,duration,and severity than the Daba Mountains.This disparity can be attributed to higher rates of temperature increase and precipitation decrease in the western Qinling Mountain.(3)Interdecadal variations in droughts in the QDM were directly influenced by the synergistic effects of interdecadal fluctuations in air temperature and precipitation.Circulation factors modulate temperature and precipitation through phase transitions,thereby affecting drought dynamics in the QDM.The Atlantic Multidecadal Oscillation emerges as the primary circulation factors influencing temperature changes,with a mid-1990s shift to a positive phase favoring warming.The East Asian Summer Monsoon and El Ni?o-Southern Oscillation are the main circulation factors affecting precipitation changes,with positive pha

关键词： drought standardized precipitation evapotranspiration index multidecadal shift transitional zone Qinling-Daba Mountains

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二氧化碳参与的三组分偶联反应进展

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有机化学 2024年第5期44卷 1506-1525页

作者：夏坤张开发 sher Wali Khan 阿布力米提·阿布都卡德尔新疆大学化学学院碳基能源化学与利用国家重点实验室拉瓦尔品第女子大学化学系

二氧化碳（CO2）是一种有吸引力的绿色可再生C1资源,将其作为反应原料或者促进剂直接参与有机合成反应,是绿色化学所倡导的研究方向.另一方面,三组分偶联反应被认为是合成化学中最具吸引力的策略之一,它能够以简单易得的原料直接合成复... 详细信息

二氧化碳（CO2）是一种有吸引力的绿色可再生C1资源,将其作为反应原料或者促进剂直接参与有机合成反应,是绿色化学所倡导的研究方向.另一方面,三组分偶联反应被认为是合成化学中最具吸引力的策略之一,它能够以简单易得的原料直接合成复杂分子.基于此,综述了将CO2作为原料或促进剂,参与的三组分偶联的反应体系,以反应生成的产物类型进行分类:羧基、酯基、羰基、烷基和氰基等一系列化合物以及CO2作为促进剂的反应体系,并对此类反应的发展做出展望.

关键词：二氧化碳绿色化学三组分偶联促进剂

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大米淀粉-多酚复合物在不同条件下的释放特性分析

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现代食品科技 2024年第5期40卷 111-118页

作者：许敏韩雪琴陈天鸽 sher Ali Khan 李泳娴徐巨才毛银光干雨泽黄立新刘磊五邑大学生物科技与大健康学院广东江门529020 江门市国际大健康创新研究院广东江门529040 华南理工大学食品科学与工程学院广东广州510640 Agriculture Research Institute Tarnab Peshawar 巴基斯坦24330 广东滨崎食品有限公司广东江门529020 佛山市朗芯生物科技有限公司广东佛山528200

该文研究了稻米中的主要单体酚(阿魏酸、没食子酸)与大米淀粉形成复合物后,多酚对α-淀粉酶和葡萄糖苷酶的活力的影响,以及复合物中多酚在不同条件下的释放特性。结果表明,在α-淀粉酶作用下,随着复合物中多酚含量从5%增加至20%,淀粉的... 详细信息

该文研究了稻米中的主要单体酚(阿魏酸、没食子酸)与大米淀粉形成复合物后,多酚对α-淀粉酶和葡萄糖苷酶的活力的影响,以及复合物中多酚在不同条件下的释放特性。结果表明,在α-淀粉酶作用下,随着复合物中多酚含量从5%增加至20%,淀粉的水解率呈下降趋势(阿魏酸组由54%降至49.69%,没食子酸组由57.97%降至49.81%)。同样,在葡萄糖苷酶作用下,没食子酸的水解率显著降低(由65.72%降至57.13%)。对于消化特性,不同添加量(由5%增加至20%)的没食子酸的加入显著降低了RDS的含量(由80.76%降至64.62%),阿魏酸的SDS含量降低(由15.69%降至14.07%),RS含量显著增加(由11.26%增加至16.69%)。复合物中阿魏酸的释放量随着水溶液的温度(30~80℃)的升高增加了131.43%。随着pH值的增加(2~6),阿魏酸的释放量呈现先降后增的趋势,而没食子酸的释放量则呈现增加的趋势。在模拟胃肠消化实验中发现,阿魏酸在胃液中提前释放,而没食子酸(5%)在肠液中释放量减小(由2.19 mg降至1.56 mg)。该研究结果可为膳食多酚在淀粉基功能食品中的应用提供理论参考。

关键词：大米淀粉阿魏酸没食子酸释放特性

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