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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 ***,multidecadal fluctuations in drought and their multifaceted influencing factors remain inadequately *** 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 *** 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 ***,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 *** 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 *** factors modulate temperature and precipitation through phase transitions,thereby affecting drought dynamics in the *** Atlantic Multidecadal Oscillation emerges as the primary circulation factors influencing temperature changes,with a mid-1990s shift to a positive phase favoring *** East Asian summer Monsoon and El Ni?o-southern Oscillation are the main circulation factors a

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

Effects of Annealing Temperature on the structural,Optical,and Electrical Properties of ZnO Thin Films Grown on n-si<100>substrates by the sol–Gel spin Coating Method

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Acta Metallurgica sinica(English Letters) 2014年第4期27卷 682-688页

作者： Aniruddh bahadur Yadav Amritanshu Pandey s.Jit Department of Electronics Engineering Centre for Research in MicroelectronicsIndian Institute of Technology (Banaras Hindu University)

The effects of annealing temperature on the sol–gel-derived ZnO thin films deposited on n-sh100 i substrates by sol–gel spin coating method have been studied in this *** structural,optical,and electrical properties of ZnO thin films annealed at 450,550,and 650 °C in the Ar gas atmosphere have been investigated in a systematic *** XRD analysis shows a polycrystalline nature of the films at all three annealing ***,the crystallite size is observed to be increased with the annealing temperature,whereas the positions of various peaks in the XRD spectra are found to be red-shifted with the *** surface morphology studied through the scanning electron microscopy measurements shows a uniform distribution of ZnO nanoparticles over the entire si substrates of enhanced grain sizes with the annealing *** properties investigated by photoluminescence spectroscopy shows an optical band gap varying in the range of 3.28–3.15 eV as annealing temperature is increased from 450 to 650 °C,*** fourpoint probe measurement shows a decrease in resistivity from 2：1 10 2to 8：1 10 4X cm with the increased temperature from 450 to 650 °*** study could be useful for studying the sol–gel-derived ZnO thin film-based devices for various electronic,optoelectronic,and gas sensing applications.

关键词： Nanocrystalline ZnO thin film sol–gel Annealing surface morphology Photoluminescence(PL) Resistivity Grain size

A New species of Fossil <i>Mus</i>(Muridae, Mammalia) from the Late Quaternary Deposits of Narmada Valley, Central India

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Open Journal of Geology 2011年第3期1卷 37-44页

作者： bahadur singh kotlia Moulishree Joshi Lalit Mohan Joshi 不详

A new species of fossil Mus (Muridae, Rodentia) is described from the Pleistocene fluviatile deposits of the Narmada valley (Central India). The species, Mus narmadaensis sp. Nov., has a comparatively smaller lower molar which is characterized by a narrow molar with well connected cusps, small anterior expansion of lingual anteroconid, protoconid and metaconid, reduced posterior cingulum in addition to hypoconid and entoconid nearly at the same level. The large M3 has centrally placed bulbous hypoconid. Among the extant species, the present one is closest to M. shortridgei in having similarly placed protoconid and metaconid in M1 and a well developed hypoconid in M3.

关键词： Fossil Mus Late Quaternary Narmada basin Central India

Crustal deformation measurements by global positioning system(GPs)along NsL,western India

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Geodesy and Geodynamics 2022年第3期13卷 254-260页

作者： Rakesh K.Dumka D.suriBabu B.s.kotlia Girish Ch.Kothyari sandip Prajapati Institute of seismological Research RaisanGandhinagarGujarat382009India Center of Advanced study in Geology Kumaun UniversityNainital263002India Adikavi Nannaya University RajahmundaryA.P.India

The Narmada son Lineament(NsL)is a major palaeo-rift system and seismically active intra-plate *** this paper,we processed and analyzed the GPs data from 2009 to 2016 to study the geodynamic characteristics of *** velocities derived from GPs were used to calculate the associated deformation and crustal strain,while the slip deficit was estimated using the horizontal motion of GPs *** investigation reveals that the maximum deformation of western NsL is 1.6 mm per year,and the upper bound of the seismic moment(M;)is 2.0×10;dyn/cm,corresponding to an earthquake of about 6.0 *** study highlights the significance of Aravalli and satpura mobile *** estimated strain of 0.03μstrain/yr is low but comparable to the stable continental region,and a close association of factors(the fragility,crustal conductors,and compressive tectonics)is considered responsible for seismogenic activities in western NsL.

关键词： GPs Intra-plate deformation strain accumulation seismic moment seismic activity

Facile Development of Iron-Platinum Nanoparticles to Harness Multifunctionality in single Entity

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Acta Metallurgica sinica(English Letters) 2016年第12期29卷 1098-1106页

作者： Madhulekha Gogoi Komanduri s. Varadarajan Anant bahadur Patel Pritam Deb Department of Physics Tezpur University (Central University) Tezpur Assam 784028 India NMR Microimaging and spectroscopy Centre for Cellularand Molecular Biology Habsiguda Hyderabad 500007 India Department of Chemistry IIT GuwahatiNorth Guwahati Assam 781039 India

Engineered magnetic nanosystems exhibit attractive options for implementing unique diagnostic options and therapeutic solutions in biomedical applications. Here we report a facile, thermo-free and aqueous synthetic method to prepare ascorbic acid-stabilized iron-platinum nanoparticles. The effects of reducing agent, pH and sequence of precursor addition are investigated, and optimized reaction condition is identified to obtain a unique iron-platinum （Pt-FePt） nanosystems. The multifunctionality of the developed nanosystem has been realized by catalytic efficiency of platinum for therapeutic application and superparamagnetic property of FePt for magnetic resonance imaging contrast enhancement. Moreover, the multifunctional imaging and therapeutic activities have been achieved at physiological pH. The developed multifunctional nanoparticles are monodisperse with uniform morphology as well as stable in solution and non-toxic.

关键词： Multifunctional superparamagnetic Magnetic resonance imaging (MRI) Therapeutic

Mineral composition and structure of the stalagmite laminae from Chulerasim cave,Indian Himalaya,and the significance for palaeoclimatic reconstruction

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Mineral composition and structure of the stalagmite laminae ...

Influence of loading and heating processes on elastic and geomechanical properties of eclogites and granulites

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： Wuhui Duan bahadur singh kotlia Ming Tan Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences Department of Geology The DurhamKumaun University

Many noteworthy properties of climate recorded by stalagmites can result from their mineralogy and fabric as well as their mode of *** this study,X-ray diffraction(XRD) and scanning electron microscope(sEM) investigations were carried out for a well laminated stalagmite from Chulerasim cave, north India,to identify the mineral composition and structure of the *** some early reported stalagmite laminae from Thailand and southwestern China,the laminae of this stalagmite are composed of alternating compact and porous *** XRD results confirm that the stalagmite is composed mainly of primary aragonite,which corrects the previous *** sEM results show that the compact sub-layer is composed of elongated columnar aragonites with a general longitudinal orientation (parallel to the vertical growth axis) and the coalescence of the aragonite crystals is well developed, leaving few inter-crystalline *** compact sub-layer may have formed in quasi-equilibrium conditions and provides the main carrier of climate *** porous sub-layer is made up of needles, drusy and fibrous aragonites intersecting each ***,the coalescence is low,with many inter-crystalline voids,which suggests a short hiatus between two adjacent compact sub-layers. Therefore,the growth of alternation of compact/porous sub-layers may not be successive,and they may have formed in different *** results suggest that,for stalagmite/palaeodimate research, cave monitoring should be performed to reveal when and how the compact sub-layers were formed.

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 127-137页

作者： Hem bahadur Motra sascha Zertani Department of Geosciences Marine and Land Geomechanics and Geotechnics University of Kiel Institut für Geologische Wissenschaften Freie Universitat Berlin

Increased knowledge of the elastic and geomechnical properties of rocks is important for numerous engineering and geoscience applications(e.g. petroleum geoscience, underground waste repositories,geothermal energy, earthquake studies, and hydrocarbon exploration). To assess the effect of pressure and temperature on seismic velocities and their anisotropy, laboratory experiments were conducted on metamorphic rocks. P-(Vp) and s-wave(Vs) velocities were determined on cubic samples of granulites and eclogites with an edge length of 43 mm in a triaxial multianvil apparatus using the ultrasonic pulse emission technique in dependence of changes in pressure and temperature. At successive isotropic pressure states up to 600 MPa and temperatures up to 600 ℃, measurements were performed related to the sample coordinates given by the three principal fabric directions(x, y, z) representing the foliation(xy-plane), the normal to the foliation(z-direction), and the lineation direction(x-direction). Progressive volumetric strain was logged by the discrete piston displacements. Cumulative errors in Vpand Vsare estimated to be sure significantly contributes to the increase in seismic velocities and decrease in anisotropies for pressures up to 200-250 MPa. Characteristic P-wave anisotropies of about 10% are obtained for eclogite and 3-4% in a strongly retrogressed eclogite as well as granulites. The wave velocities were used to calculate the geomechanical properties(e.g. density, Poisson’s ratio, volumetric strain, and elastic moduli) at different pressure and temperature conditions. These results contribute to the reliable estimate of geomechanical properties of rocks.

关键词： Anisotropy Elastic wave velocities Dynamic elastic moduli Geomechanical rock properties Microcrack

Factors affecting technical efficiency of small-scale apple farms in Balochistan Plateau, Pakistan

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Journal of Mountain science 2017年第4期14卷 782-794页

作者： Ghulam MURTAZA Gopal bahadur THAPA Disaster Management and Development studies University of Balochistan school of Environment Resources and Development Asian Institute of Technology

In Balochistan, Agriculture is dominated by small-scale farmers and the apple production sector is confronted with the chronic constraint of low output per unit of input. Although some agricultural policies have been implemented in this province, studies on effectiveness and impacts of such policies over apple production and farmers' performance are still limited. This study is an effort to bridge the research gap on this potential crop in the plateau by investigating technical and scale efficiency of 181 officially designated small-scale apple farmers in mountainous district Mastung in Balochistan; then explored factors that underlie differences in production inefficiency. A two-stage input-oriented Data Envelopment Analysis(DEA) methodology was employed to evaluate technical and scale efficiency followed by truncated bootstrapped regression framework to analyze the correlative determinants to efficiency. Average technical and scale efficiencies of larger landholders were higher than medium and small landholders. Analysis indicated that there is still ample scope for inefficient sample farmers to reduce the input use by 33% without compromising the given yield level. Maximum contributions to the total input savings were from the use of urea, farm yard manure(FYM) and labor-use. Farmer's experience, farm ownership, irrigation constraints, and farmer's access to trainings, credit and extension services significantly affected apple farmers' technical efficiency. Based on the findings of this study, strategies are suggested to enhancing efficiencies by farmers' capacity development through effective extension services and trainings and provision of adequate credit.

关键词： small-scale apple farmers Technical efficiency Data envelopment analysis (DEA) Bootstrap Efficiency-improving resources Balochistan Plateau

species Richness, Diversity and Density of Understory Vegetation along Disturbance Gradients in the Himalayan Conifer Forest

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Journal of Mountain science 2014年第5期11卷 1182-1191页

作者： Kesang WANGCHUK András DARABANT Prem bahadur RAI Maria WURZINGER Werner ZOLLITsCH Georg GRATZER University of Natural Resources and Life sciences Department of Sustainable Agricultural Systems Division of Livestock SciencesGregor Mendel Strasse 33A Vienna 1180 Austria Renewable Natural Resources Research and Development Center University of Natural Resources and Life sciences Department of Forest and Soil Sciences Institute of Forestry Ecology Peter Jordan Strasse 82A Vienna 1190 Austria

We investigated whether species richness, diversity and density of understory herbaceous plants differed along logging(gap) and grazing(primarily by cattle) disturbance gradients, and sought to identify drivers of richness, diversity and density of understory vegetation of logged sites. A factorial experiment was conducted in the mixed conifer forest of Gidakom in Western Bhutan. Levels of the logging treatment included small(0.15 – 0.24 ha), medium(0.25 – 0.35 ha) and large(0.36 – 1.31 ha) gaps. The grazing treatment included grazed(primarily by cattle) and ungrazed(where herbivores were excluded by a fence) plots nested within each gap. Data were collected from 12 gaps(4 replicates at each level of logging) using the point intercept method. shannon Weaver Diversity and Margalef's indices were used to estimate species diversity and describe species richness, respectively. soil samples were analyzed for pH and nutrients. The interaction effect of logging and grazing was significant(p≤0.001) only on species diversity. Relative to ungrazed areas, species diversity was significantly higher(0.01≤p≤0.05) in medium grazed gaps. Under grazed conditions, soil P was negatively correlated with gap size and species diversity. While species diversity was positivelycorrelated(0.01≤p≤0.05) with soil N in grazed plots species richness was positively correlated(0.001≤p≤0.01) with soil N in ungrazed plots. Relative density of Yushania microphylla and Carex nubigena were higher under ungrazed conditions. Our study suggests that the combined effect of cattle grazing and logging results in higher species diversity of understory vegetation in medium and grazed gaps in mixed conifer forests of Bhutan,whereas increase or decrease in relative density of major species is determined primarily by the independent effects of grazing and logging. From management perspective, forest managers must refrain from creating large gaps to avoid loss of nutrients(mainly P and N), which may eventually aff

关键词： Forest gap Grazing Relative density soil nutrients species diversity species richness