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synthesis and characterization of rare earth metal doped tungsten trioxide photocatalyst for degradation of Rhodamine B dye

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稀土学报:英文版 2023年第9期41卷 1302-1310,I0002页

作者： Pooja Nehra Amita Khatri Anil Kumar satyendra singh Pawan s.rana Department of Physics Deenbandhu Chhotu Ram University of Science and TechnologyMurthal1339SonipatHaryanaIndia special Centre for Nanoscience Jawaharlal Nehru University New Delhi10067India

Nowadays,it is concern for researchers that due to high recombination rate of photogenerated charge carriers in tungsten trioxide(WO_(3)) nanoparticles,the future applications are limited in the field of *** we attempt to synthesize tungsten trioxide nanoparticles with different doping concentrations of lanthanum i.e.2 wt%,4 wt%,6 wt% and 8 wt%.The synthesized samples were characterized by using various characterization techniques:X-ray diffraction(XRD),Raman spectroscopy,Fourier transform infrared spectroscopy(FTIR),photoluminescence spectra(PL),transmission electron microscopy(TEM),energy dispersive X-ray(EDX) and UV-Vis ***_(3) retains its monoclinic structure even after doping which was confirmed by XRD *** helps to descry functional groups present in the *** size of nanoparticles was calculated by using *** confirms the absence of any impurity in the synthesized *** spectroscopy confirms the presence of a large number of imperfections induced in the lattice of WO_(3).The rate of recombination was analyzed by photoluminescence(PL) spectroscopy and is minimum in 4 wt% doping of *** optical bandgap was calculated using UV-Vis spectroscopy and becomes narrow along with the doping ***,it is found that doping of La in WO_(3) has considerably ameliorate the photocatalytic activity by reducing rate of recombination due to the trapping of electrons by defects introduced in the *** decolorization of Rhodamine B(RhB) dye was performed and the values of c/c_0 and rate constant(k) confirm that the 4 wt% doping shows maximum degradation *** kinetic study for photodegradation of Rhodamine B was done by using various kinetic models and results show that the reaction follows first order kinetics very ***,optimum doping of lanthanum increases the decolorization ability of WO_(3) towards RhB dye.

关键词： Photocatalytic activity WO_(3)nanoparticles Rhodamine B dye Rare earth doping Visible light

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Extraction,Utilization Pattern and Prioritization of Fuel Resources for Conservation in Manali Wildlife sanctuary,Northwestern Himalaya

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Journal of Mountain science 2012年第4期9卷 580-588页

作者： Man s.rana sakshi B.rana s.s.sAMANT Department of Plant sciences Government CollegeBanjar-Kullu175123Himachal PradeshIndia Department of Plant sciences Government CollegeKullu175101Himachal PradeshIndia G.B.Pant Institute of Himalayan Environment&Development Himachal UnitMohal-Kullu175126Himachal PradeshIndia

Fuelwood is the main source of the energy in mountainous ***,annual wood consumption is very *** on fuelwood resources,and their extraction and availability is very ***,present study was carried out to study the diversity of fuelwood species,annual collection,preference and availability of fuel species in the *** four species(25 trees and 9 shrubs) were extracted for fuel by the *** collection and species preference was highest for Picea smithiana,Cedrus deodara,Indigofera heterantha,Pinus wallchiana and sorbaria tomentosa,*** use index indicating use pressure was highest for ***,***,*** and Abies pindrow,*** native species,some non-native horticultural and agroforestry species such as Malus pumila,***,Celtis australis,*** also being used as *** species showed their availability in eight forest types whereas,population and regeneration status was ***,immediate actions are suggested to sustain current and future demand of *** afforestation of degraded,uncultivated and marginal lands through high quality and preferred fuel species might reduce pressure on wild and selective species.

关键词：野生动物保护区燃料资源北喜马拉雅提取优先次序保育薪柴资源燃料种类

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Twitter Arabic sentiment Analysis to Detect Depression Using Machine Learning

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Computers, Materials & Continua 2022年第5期71卷 3463-3477页

作者： Dhiaa A.Musleh Taef A.Alkhales Reem A.Almakki shahad E.Alnajim shaden K.Almarshad rana s.Alhasaniah sumayh s.Aljameel Abdullah A.Almuqhim Department of Computer science College of Computer Science and Information TechnologyImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia

Depression has been a major global concern for a long time,with the disease affecting aspects of many people’s daily lives,such as their moods,eating habits,and social *** Arabic culture,there is a lack of awareness regarding the importance of facing and curing mental health ***,people all over the world,including Arab citizens,tend to express their feelings openly on social media,especially Twitter,as it is a platform designed to enable the expression of emotions through short texts,pictures,or *** are inclined to treat their Twitter accounts as diaries because the platform affords them *** published studies have detected the occurrence of depression among Twitter users on the basis of data on tweets posted in English,but research on Arabic tweets is *** aim of the present work was to develop a model for analyzing Arabic users’tweets and detecting depression among Arabic Twitter *** expand the diversity of user tweets,by adding a new label(“neutral”)so the dataset include three classes(“depressed”,“non-depressed”,“neutral”).The model was created using machine learning classifiers and natural language processing techniques,such as support Vector Machine(sVM),Random Forest(RF),Logistic Regression(LR),K-nearest Neighbors(KNN),AdaBoost,and Naïve Bayes(NB).The results showed that the RF classifier outperformed the others,registering an accuracy of 82.39%.

关键词： Depression sentiment analysis twitter supervised learning machine learning

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Unraveling the nature of sensing in electrostatic MEMs gas sensors

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Microsystems & Nanoengineering 2024年第3期10卷 109-117页

作者： Yasser s.shama sasan Rahmanian Hamza Mouharrar rana Abdelrahman Alaaeldin Elhady Eihab M.Abdel-Rahman systems Design Engineering University of Waterloo200 University Ave WWaterloo N2L 3G1 ONCanada Mechanical Engineering Benha Faculty of EngineeringBenha UniversityBenha 13511Egypt

This paper investigates the fundamental sensing mechanism of electrostatic MEMs gas *** compares among the responsivities of a set of MEMs isopropanol sensors before and after functionalization,and in the presence and absence of electrostatic fields when operated in static and dynamic detection *** the static mode,we found that the sensors do not exhibit a measurable change in displacement due to added *** the other hand,bare sensors showed a clear change in displacement in response to isopropanol *** the dynamic mode,functionalized sensors showed a measurable frequency shift due to the added mass of isopropanol *** the presence of strong electrostatic fields,the measured frequency shift was found to be threefold larger than that in their absence in response to the same concentration of isopropanol *** enhanced responsivity of dynamic detection allows the sensors to measure the vapor mass captured by the functional material,which is not the case for static *** detection of isopropanol by bare sensors in static mode shows that change in the medium permittivity is the primary sensing *** enhanced responsivity of dynamic mode sensors when operated in strong electrostatic fields shows that their sensing mechanism is a combination of a weaker added mass effect and a stronger permittivity *** findings show that electrostatic MEMs gas sensors are independent of the direction of the gravitational field and are,thus,robust to changes in *** is erroneous to refer to them as‘gravimetric’sensors.

关键词： mechanism. electrostatic measurable

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some Investigations on Hybrid Fuzzy IPD Controllers for Proportional and Derivative Kick suppression

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International Journal of Automation and computing 2016年第5期13卷 516-528页

作者： Vineet Kumar K.P.s.rana Division of Instrumentation and Control Engineering Netaji Subhas Institute of Technology(NSIT)

Proportional and derivative kick i.e., a large change in control action of a proportional plus integral plus derivative （PID） controller due to a sudden change in reference set-point is generally undesired in process industry. Therefore, the structure of conventional parallel PID controller is modified to integral minus proportional derivative （I-PD） controller. In this paper, three hybrid fuzzy IPD controllers such as a fuzzy I-fuzzy PD （FI-FPD） controller and its hybrid combinations with its conventional counterpart such as fuzzy I-PD （FI-PD） and I-fuzzy PD （I-FPD） are presented in view of above industrial problem. These controllers are based upon the counterpart conventional I-PD controller and contains analytical formulae. Computer simulations are carried out to evaluate the performance of hybrid fuzzy controllers along with conventional I-PD and PID controllers for set-point tracking and disturbance rejection for an induction motor in closed loop using LabVIEWTM environment. The gains of conventional and hybrid fuzzy controllers are tuned using genetic algorithm （GA） for minimum overshoot and settling time. It has been observed that hybrid fuzzy controllers along with the conventional I-PD controller significantly remove the kick from the control action in reference set-point tracking. However, in disturbance rejection, I-PD and FI-PD controllers fail to eliminate the kick from the control signal. In contrast, FI-FPD and I-FPD controllers considerably reduced spikes from the control action in disturbance rejection. Among the conventional and hybrid fuzzy IPD controllers, FI--FPD demonstrates much better set-point tracking and disturbance rejection response with spike free control action.

关键词： Proportional plus integral plus derivative (PID) integral minus proportional derivative (I-PD) hybrid fuzzy IPD con- troller proportional kick derivative kick.

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An Overview of PRP-Delivering scaffolds for Bone and Cartilage Tissue Engineering

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Journal of Bionic Engineering 2024年第2期21卷 674-693页

作者： somayeh Baghersad Behzad Bolandi rana Imani shabnam Afaghi samira Davoudinia Department of Textile Engineering Amirkabir University of Technology(Tehran Polytechnic)Tehran159163-4311Iran Department of Biomedical Engineering Amirkabir University of Technology(Tehran Polytechnic)Tehran159163-4311Iran

Tissue engineering is nowadays an emerging approach that aims to replace or regenerate diseased or damaged organs with engineered constructs. Considering the key role of growth factors (GFs) in the tissue regeneration process, these biomolecules are considered an important part of the tissue engineering process, so the presence of growth factors in engineered scaffolds can accelerate tissue regeneration by influencing the behavior of cells. Platelet-rich plasma (PRP), as an autologous source of a variety of growth factors, is considered a therapeutic agent for the treatment of degenerative diseases. Regarding its ability to promote the healing process and tissue regeneration, PRP therapy has attracted great attention in bone and cartilage tissue engineering. Incorporating PRP and its derivatives into engineered scaffolds not only bioactivates the scaffold, but the scaffold matrix also acts as a sustained and localized growth factor release system. In addition, the presence of a scaffold can promote the bioactivity of GFs by providing an environment that facilitates their interaction, leading to enhanced effects compared to their free form. This review presents a brief overview of PRP's role in bone and cartilage tissue regeneration with the main focus on scaffold-mediated PRP delivery. In addition, the classification of platelet-rich products, current extraction techniques, terminology, and scaffold bioactivation methods are presented to provide a better understanding of the basics and the key aspects that may affect the effectiveness of therapy in bone and cartilage tissue engineering.

关键词： Platelet-rich plasma Growth factors delivery scaffold Bone Cartilage

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Plant Communities and Factors Responsible for Vegetation Pattern in an Alpine Area of the Northwestern Himalaya

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Journal of Mountain science 2011年第6期8卷 817-826页

作者： Man s.rana s.s.sAMANT Y.s.RAWAT Department of Plant science Government Degree College G.B.Pant Institute of Himalayan Environment & Development Department of Botany D.S.B.CampusKumaun University

The study intended to describe the alpine vegetation of a protected area of the northwestern Himalaya and identify the important environmental variables responsible for species *** placed random plots covering different habitats and altitude to record species composition and environmental *** was classified using hierarchical cluster analysis and vegetation-environment relationships were evaluated with Canonical Correspondence *** communities,each in alpine shrub and meadows were delineated and well justified in the ordination *** species for the different communities were *** species richness and diversity were found in community IV among shrub communities and community II among the *** environmental variables explained 61.5% variation in shrub vegetation and 59.8% variation in *** variables explained higher variability (～35%) than spatial variables (～21%) in both shrubs and ***,among the spatial variables and carbon/nitrogen ratio and nitrogen among the soil variables explained maximum *** 40% variations left *** and species diversity among the other variables had significant correlation with ordination *** showed that altitude and C/N ratio played a significant role in species *** sampling efforts and inclusion of other non-studied variables are also suggested for better understanding.

关键词：北喜马拉雅植被格局高山地区植物群落物种多样性环境变量典范对应分析海拔高度

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Transverse Transport of Polymeric Nanofluid under Pure Internal Heating: Keller Box Algorithm

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Communications in Theoretical Physics 2018年第7期69卷 106-118页

作者： R.Mehmood s.rana E.N.Maraj Department of Mathematics Faculty of Natural Sciences HITEC University

The present work aims to investigate transverse Oldroyd-B nanofluid flow on a stretched panel with consideration of internal heat generation. Buongiorno model is utilized to study influence of thermophoresis and Brownian motion effects. A numerical procedure known as Keller box algorithm is used to solve the governed physical *** velocity, temperature and concentration of nanoparticles are expressed. Also, concerned physical measures such as heat and mass transfer are investigated numerically. The simulations performed revealed that fluid parameters play a significant role in heat transfer under Brownian motion and thermophoresis effects. Local heat flux is elevated while local mass flux is suppressed with enhancing Brownian motion parameter. streamlines pattern exhibits that flow is more inclined in the presence of Deborah number effects. To the best of our knowledge, transverse flow of an Oldroyd-B type fluid which incorporates the thermal relaxation effects has never been reported before in the presence of Brownian motion and internal heating phenomenon. Therefore we intend to discuss these features in detail. The obtained results are a novel contribution, which can be benchmark for further relevant academic research related to polymer industry.

关键词：聚合物工业子算法 Brownian 加热运输运动效果热流动运动参数

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Pleistocene glaciation advances the cryptic speciation of stellera chamaejasme *** a major biodiversity hotspot

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Journal of Integrative Plant Biology 2024年第6期66卷 1192-1205页

作者： santosh Kumar rana Hum Kala rana Jacob BLandis Tianhui Kuang Juntong Chen Hengchang Wang Tao Deng Charles C.Davis Hang sun CAs Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Arkansas Biosciences Institute Arkansas State UniversityJonesboroArkansas 72401USA school of Integrative Plant science Section of Plant Biology and the L.H.Bailey HortoriumCornell UniversityIthacaNew York 14853USA BTI Computational Biology Center Boyce Thompson InstituteIthacaNew York 14853USA CAs Key Laboratory of Plant Germplasm Enhancement and specialty Agriculture Chinese Academy of SciencesWuhan Botanical GardenWuhan 430074China Department of Organismic and Evolutionary Biology HerbariaHarvard UniversityCambridgeMassachusetts 02138USA

The mountains of southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate *** high species diversity in this mountain system has long been attributed to a complex set of factors,and recent large-scale macroevolutionary investigations have placed a broad timeline on plant diversification that stretches from 10 million years ago(Mya)to the *** our increasing understanding of the temporal mode of speciation,finer-scale populationlevel investigations are lacking to better refine these temporal trends and illuminate the abiotic and biotic influences of cryptic *** is largely due to the dearth of organismal sampling among closely related species and populations,spanning the incredible size and topological heterogeneity of this *** study dives into these evolutionary dynamics of speciation using genomic and ecomorphological data of stellera chamaejasme *** identified four previously unrecognized cryptic species having indistinct morphological traits and large metapopulation of evolving lineages,suggesting a more recent diversification(~2.67-0.90 Mya),largely influenced by Pleistocene glaciation and biotic *** factors likely influenced allopatric speciation and advocated cyclical warming–cooling episodes along elevational gradients during the *** study refines the evolutionary timeline to be much younger than previously implicated and raises the concern that projected future warming may influence the alpine species diversity,necessitating increased conservation efforts.

关键词： cryptic speciation glacial-interglacial Hengduan Mountains north-south migration stellera chamaejasme

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Free Convective Nonaligned Non-Newtonian Flow with Non-linear Thermal Radiation

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Communications in Theoretical Physics 2016年第12期65卷 687-693页

作者： s.rana R.Mehmood PV s.Narayana N.s.Akbar Department of Mathematics Faculty of Natural Sciences HITEC University Taxila Cantt Pakistan Department of Mathematics VIT University Vellore India National University of sciences and Technology (NUsT) Islamabad 44000 Pakistan

The present study explores the free convective oblique Casson fluid over a stretching surface with non-linear thermal radiation effects. The governing physical problem is modelled and transformed into a set of coupled non-linear ordinary differential equations by suitable similarity transformation, which are solved numerically with the help of shooting method keeping the convergence control of 10^(-5) in computations. Influence of pertinent physical parameters on normal, tangential velocity profiles and temperature are expressed through graphs. Physical quantities of interest such as skin friction coefficients and local heat flux are investigated numerically.

关键词：非热辐射自由对流非牛顿流非线性常微分方程 Casson流体物理问题相似变换数值求解

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