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Assessment of geochemical and sedimentological characteristics of atmospheric dust in Shiraz,southwest Iran

Geoscience Frontiers 2020年第3期11卷 783-792页

作者： Amir Karimian Torghabeh Biswajeet pradhan Ashkan Jahandari Department of Earth Sciences Faculty of SciencesShiraz UniversityShirazIran The Centre for Advanced Modeling and Geospatial Information Systems(CAMGIS) Faculty of Engineering and ITUniversity of Technology SydneySydneyNSW2007Australia Department of Energy and Mineral Resources Engineering Sejong UniversityChoongmu-gwan209 Neungdong ro Gwangjin-guSeoul05006South Korea Department of Geology Shahid Bahonar University of KermanKermanIran

Geogenic dust is commonly believed to be one of the most important environmental problems in the Middle *** present study investigated the geochemical characteristics of atmospheric dust particles in Shiraz City(south of Iran).Atmospheric dust samples were collected through a dry collector method by using glass trays at 10 location sites in May *** composition was analysed through inductively coupled plasma optical emission *** data showed that the dustiest days were usually in spring and summer,particularly in April.X-ray diffraction analysis of atmospheric dust samples indicated that the mineralogical composition of atmospheric dust was calcite+dolomite(24%)>palygorskite(18%)>quartz(14%)>muscovite(13%)>albite(11%)>kaolinite(7%)>gypsum(7%)>zircon=anatase(3%).The high occurrence of palygorskite(16%-23%) could serve as a tracer of the source areas of dust storms from the desert of Iraq and Saudi Arabia to the South of *** electron microscopy indicated that the sizes of the collected dust varied from 50 μm to0.8 μm,but 10 μm was the predominant *** atmospheric dust collected had prismatic trigonal-rhombohedral crystals and semi-rounded irregular ***,diatoms were detected in several samples,suggesting that emissions from dry-bed lakes,such as Hoor Al-Azim Wetland(located in the southwest of Iran),also contributed to the dust *** trajectory simulations were performed at the date of sampling by using the NOAA HYSPLIT *** showed that the sources of atmospheric dust in the study area were the eastern area of Iraq,eastern desert of Saudi Arabia,Kuwait and Khuzestan *** Ca/Al ratio of the collected samples(1.14) was different from the upper continental crust(UCC) value(UCC=0.37),whereas Mg/A1(0.29),K/Al(0.22) and Ti/Al(0.07) ratios were close to the UCC value(0.04).This condition favours desert calcisols as the main mineral dust *** of the crustal enrichment factor(EF

关键词： Dust storm Atmospheric dust Heavy metals Diatom Palygorskite Provenance

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The Rise of China in Central Asia： The New Silk Road Diplomacy

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Fudan Journal of the Humanities and Social Sciences 2018年第1期11卷 9-29页

作者： Ramakrushna pradhan Department of Social Science Fakir Mohan University Nuapdhi Balasore Odisha 756020 India

China＇s relationship with Central Asia has grown manifold since the foundation of Shanghai Five in 1996, which in June 2001 became the Shanghai Cooperation Organisation. The impetus to the relationship has further been accen- tuated when China-Russia friendship treaty was signed in July 2001. The US-led war in Afghanistan against Taliban and A1-Qaeda has yet again cemented Chinese position in Central Asia, and the recently concluded Belt and Road Initiative （BRI） has undeniably dramatically underscored the strategic value of Central Asia to the west and has opened up possibilities for Chinese security, political and economic interests. Geostrategically enmeshed with Central Asia, China will remain an integral and increasingly influential player in Central Asia. This research paper contextualises China＇s emergence and interests in Central Asia discarding the much talked about great game thesis and asserts by analysing the rise of China in the region as an unmatched and unchallenged power which has been testified once again with the recent BRI of Beijing.

关键词： China Central Asia BRI New Silk Road Geopolitics

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Potentials of GaP as millimeter wave IMPATT diode with reference to Si,GaAs and GaN

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红外与毫米波学报 2019年第4期38卷 395-402页

作者： Janmejaya pradhan S K Swain S R Pattnaik G N Dash College of Engineering Bhubaneswar Bhubaneswar Odisha 752024 India National Institute of Science and Technology Berhampur Odisha 761008 India School of Physics Sambalpur University Sambalpur Odisha 768019 India

This paper presents the simulation results of DC,small-signal and noise properties of GaP based Double Drift Region( DDR) Impact Avalanche Transit Time( IMPATT) diodes. In simulation study we have considered the flat DDR structures of IMPATT diode based on GaP,GaAs,Si and GaN( wurtzite,wz) material. The diodes are designed to operate at the millimeter window frequencies of 94 GHz and 220 GHz. The simulation results of these diodes reveal GaP is a promising material for IMPATT applications based on DDR structure with high break down voltage( V_B) as compared to Si and GaAs IMPATTs. It is also encouraging to worth note GaP base IMPATT diode shows a better output power density of 4. 9 × 10~9 W/m^2 as compared to Si and GaAs based IMPATT diode. But IMPATT diode based on GaN( wz) displays large values of break down voltage,efficiency and power density as compared to Si,GaAs and GaP IMPATTs.

关键词： lmpact avalanche transit time(IMPATT) GaP GaN microwave and millimetre wave

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Separation of copper and iron from chloride media using Cyanex 921 in kerosene

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Journal of Central South University 2014年第5期21卷 1752-1755页

作者： Sanghamitra pradhan Niharbala Devi Sujata Mishra Department of Chemistry Institute of Technical Education and ResearchSiksha'O'Anusandhan University

The extraction and separation of Cu(Ⅱ)and Fe(Ⅲ)from HCl media using Cyanex 921 in kerosene were *** effect of shaking time,aqueous phase acid concentration,Fe(Ⅲ)/Cu(Ⅱ)concentration,Cyanex 921 concentration,temperature and aqueous to organic phase ratio on the separation of Cu(Ⅱ)and Fe(Ⅲ)was studied using 0.1 mol/L Cyanex 921 in *** separation was achieved from 2 mol/L HCl containing 0.001 mol/L Cu(Ⅱ)and 0.005 mol/L Fe(Ⅲ)with 0.1 mol/L Cyanex 921 in *** separation of copper and iron was also possible from 5 mol/L HCl using 0.02 mol/L Cyanex 921.

关键词： solvent extraction copper iron hydrochloric acid Cyanex 921

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A rare case of pigmented Bowen disease of the nail fold

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Chinese Medical Journal 2020年第12期133卷 1503-1504页

作者： Sushmita pradhan Si-Liang Xue Department of Dermatovenereology West China HospitalSichuan UniversityChengduSichuan 610041China

To the Editor:Bowen disease(BD)is a squamous cell carcinoma in situ that can progress into invasive carcinoma.[1]Pigmented BDis a rare variant of squamous cell carcinoma in situ that can be diagnosed *** is usually characterized by slow-growing,welldefined,and non-uniform hyperpigmented plaque.[2]It is also characterized by the increased melanin pigment in the epidermis or papillary dermis in addition to the alteration of *** a study,7(1.67%)of 420 BD cases were pigmented.[1]Although the exact underlying mechanism of pigmented BD is unclear,pigmentation is due to the presence of an increased number of melanocytic hyperplasia by hypertrophic dendritic processes dispersed through the tumor.[3]Pigmented BD with no scaling and keratosis indicates well-differentiated stages of atypical keratinocytes developing melanin.[3]Later atypical keratinocytes result in loss of pigmentation,keratosis,and ***,we present a rare case of pigmented BD on the proximal nail fold.

关键词： Bowen squamous rare

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S-transformation based integrated approach for spectrum estimation, storage, and sensing in cognitive radio

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Digital Communications and Networks 2019年第3期5卷 160-169页

作者： Pyari Mohan pradhan Ganapati Panda Department of Electronics and Communication Engineering Indian Institute of Technology Roorkee Uttarakhand 247667 India Electronics and Telecom Engineering Department C. V. Raman Colledge of Engineering Bhubaneswar Odisha 752054 India

Cognitive Radio (CR) uses the principle of dynamic spectrum allocation to improve the utilization of spectrum bands. The estimation of missing data is essential for maintaining an uninterrupted quality of service in the CR. However, the existing methods are not suitable for interpolating missing data in high frequency signals. The storage of spectrum occupancy information is crucial for learning the spectrum usage and prediction. The existing techniques for wideband spectrum sensing suffer from poor edge detection capabilities. This paper proposes an STransformation (ST) based approach to solve these problems. For missing samples, the proposed method improves the accuracy of estimation. The ST can also be used to store the spectrum occupancy information. The simulation results show that the proposed scheme outperforms others by improving the accuracy of edge detection. Further, the simple implementation of the ST in the frequency domain is an advantage for the real time application.

关键词： Cognitive radio S-transformation Missing data estimation Wideband sensing Spectrum occupancy

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Nano-formulations for transdermal drug delivery:A review

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Chinese Chemical Letters 2018年第12期29卷 1713-1724页

作者： Xingli Zhou Ying Hao Liping Yuan Sushmita pradhan Krista Shrestha Ojaswi pradhan Hongjie Liu Wei Li Department of Dermatovenereology State Key Laboratory of BiotherapyWest China HospitalSichuan University

Transdermal drug delivery refers to a means of delivering drugs through the surface of the skin for local or systemic treatment. The drug functions after absorption through the skin into the systemic circulation via capillary action at a certain rate. Use of traditional physical and chemical enhancers to improve the transdermal permeation rate by increasing drug solubility, diffusion coefficient, and reservoir effect is not feasible owing to the toxic side effects of the overuse of chemical penetration enhancers. Nanoformulations generally vary in size and range from 10 nm to 100 nm. The smaller particle size leads to increased drug permeability, stability, retention, and targeting, making nano-formulations suitable for transdermal drug delivery. The different applications of nano-formulations(vesicles or nanoparticles and nanoemulsions) have been widely studied. Here, the classification, characteristics, transdermal mechanism, and application of the most popular nano-formulations in transdermal drug delivery system are reviewed.

关键词： Nano-formulation Transdermal drug delivery system Classification Mechanism Application

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River Rafting in Mountainous Regions of Uttarakhand:Impacts,Suggested Mitigation Measures and Sustainability

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Journal of Mountain Science 2012年第4期9卷 511-522页

作者： Parth Sarathi MAHAPATRA Rajiv PANDEY Sonali pradhan Forest Research Institute DehradunUttarakhandIndia CSIR-Institute of Minerals and Materials Technology BhubaneswarOdishaIndia HNBG University SrinagarUttarakhandIndia Orissa University of Agriculture and Technology BhubaneswarOdishaIndia

Uttarakhand state in India is well known for its mountainous ecosystems, traditional communities and a variety of ecotourism destinations. Among various tourism activities, River Rafting along the banks of the Ganges River has increased tremendously for two decades, and has had unprecedented impacts on the traditional communities and the bio-diversity. Therefore, it is meaningful to do a comprehensive study on the various impacts associated with river rafting so as to suggest the pathways to achieve the environmental sustainability in this region. In this study, we collected primary data from randomly selected population units across all stake holders such as local people （n = too）, and camp personnel （n = 22）, through a pre-tested questionnaire survey between August 2009 and May 2010. The questionnaire contains issues on culture, social, economic, institutional and associated perceived impacts on pollution and biodiversity including views for sustainability. Secondary information was also collected from various sources and government records to supplement and strengthen the analysis. The impacts were analyzed qualitatively through a ranking mechanism to facilitate the decision making process. The perception of the interviewee about the various possible impacts of rafting was discussed with mitigating mechanism. The ranking analysis as percollected data reveals that economy and education of local community was improved significantly; however aquatic and terrestrial fauna, social cohesion and pollution （water, air, land） were significantly deteriorated. The results show that the existing practices are not sufficient to address the adverse impacts. Improvement in practices is necessary, mainly in the policy regime. Based on the analysis, some measures are recommended on how to protect community interest and environment with the development of river rafting as an ecotourism opportunity.

关键词： Eco-tourism The Ganges Impactranking Traditional community

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Oxygen Barrier of Multiwalled Carbon Nanotube/Polymethyl Methacrylate Nanocomposites Prepared by in situ Method

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Journal of Materials Science & Technology 2012年第5期28卷 391-395页

作者： Ajaya K. pradhan Sarat K. Swain Department of Chemistry North Orissa University Takatpur Baripada 757003 India Department of Chemistry Veer Surendra Sai University of Technology Burla Sambalpur 768018 India

Multiwalled carbon nanotubes （MWCNTs）/poly（methyl methacrylate）（PMMA） nanocomposites were prepared by ultrasonic assisted emulsifier free emulsion polymerization technique with variable concentration of functionalized carbon nanotubes. MWCNTs were functionalized with H 2 SO 4 and HNO 3 with continuing sonication and polished by H 2 O 2 . The appearance of Fourier transform infrared absorption bands in the PMMA/MWCNT nanocomposites showed that the functionalized MWCNT interacted chemically with PMMA macromolecules. The surface morphology of functionalized MWCNT and PMMA/MWCNT nanocomposites were studied by scanning electron microscopy. The dispersion of MWCNT in PMMA matrix was evidenced by high resolution transmission electron microscopy. The oxygen permeability of PMMA/MWCNT nanocomposites gradually decreased with increasing MWCNT concentrations.

关键词： Nanocomposites Morphology Permeability Dispersion

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A Plane-Symmetric Inhomogeneous Cosmological Model of Perfect Fluid Distribution with Electromagnetic Field Ⅰ

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Communications in Theoretical Physics 2010年第7期54卷 191-196页

作者： Anirudh pradhan Prashant KumarSingh Anil Kumar Yadav Department of Mathematics Hindu Post-Graduate College Department of Physics Anand Engineering College(Sharada Group of Institutions)

A plane-symmetric inhomogeneous cosmological model of perfect fluid distribution with electro-magnetic field is obtained. F12 is the non-vanishing component of electromagnetic field tensor. To get a deterministic solution, we assume the free gravitational field is Petrov type-Ⅱ non-degenerate. Some physical and geometric properties of the model are also discussed.

关键词： cosmology electromagnetic field inhomogeneous solution

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