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Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball mill spillage

Frontiers of Environmental Science & Engineering 2013年第2期7卷 281-293页

作者： sandeep PANDA Nilotoala PRADHAN Umaballav MOHAPATRA sandeep k. PANDA Swagat S.RATH Danda S. RAO Bansi D. NAYAk Lala B. SUkLA Barada k. MISHRA CSIR-Institute of Minerals and Materials Technology Bhubaneswar 751013 India Department of Botany North Orissa University Baripada 757003 India Regional Center of Central Tuber Crops Research Institute Bhubaneswar 751019 India

Bioleaching of a low grade chalcopyrite （ball mill spillage material） was tested for copper recovery in shake flasks. The original samples （as received） were thermally activated （600℃, 30 min） to notice the change in physico-chemical and mineralogical characteristics of the host rock and subsequently its effect on copper recovery. A mixed culture of acidophilic chemolithotrophic bacterial consortium predominantly entailing Acidithiobacillus fer- rooxidans strain was used for bioleaching studies and optimization of process parameters of both original and thermally activated samples. Mineralogical characteriza- tion studies indicated the presence of chalcopyrite, pyrite in the silicate matrix of the granitic rock. Field emission scanning electron microscopy coupled with Energy dispersive spectroscopy （FESEM-EDS） and X-ray Fluor- escence （XRF） analysis indicated mostly SiO2. With pH 2, pulp density 10% w/v, inoculum 10% v/v, temperature 30~C, 150 ***-~, 49% copper could be recovered in 30 days from the finest particle size （- 1 ~ 0.75 mm） of the original spillage sample. Under similar conditions 95% copper could be recovered from the thermally activated sample with the same size fraction in 10 days. The study revealed that thermal activation leads to volume expansion in the rock with the development of cracks, micro and macro pores on its surface, thereby enabling bacterial solution to penetrate more easily into the body, facilitating enhanced copper dissolution.

关键词： ball mill spillage thermal activation bioleaching copper

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Hepatocellular carcinoma in non-alcoholic steatohepatitis:Current knowledge and implications for management

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World Journal of Hepatology 2017年第11期9卷 533-543页

作者： George Cholankeril Ronak Patel sandeep khurana Sanjaya k Satapathy Division of Gastroenterology and Hepatology Methodist University Hospital Transplant Institute University of Tennessee Health Sciences Center Department of Medicine University of Alabama at Birmingham Montgomery Health Center Division of Gastroenterology Georgia Regents University

With the prevalence of hepatitis C virus expected to decline, the proportion of hepatocellular carcinoma(HCC) related to non-alcoholic steatohepatitis(NASH) is anticipated to increase exponentially due to the growing epidemic of obesity and diabetes. The annual incidence rate of developing HCC in patients with NASH-related cirrhosis is not clearly understood with rates ranging from 2.6%-12.8%. While multiple new mechanisms have been implicated in the development of HCC in NASH; further prospective long-term studies are needed to validate these findings. Recent evidence has shown a significant proportion of patients with non-alcoholic fatty liver disease and NASH progress to HCC in the absence of cirrhosis. Liver resection and transplantation represent curative therapeutic options in select NASHrelated HCC patients but have placed a significant burden to our healthcare resources and utilization. Currently NASH-related HCC is the fastest growing indication for liver transplant in HCC candidates. Increased efforts to implement effective screening and preventative strategies, particularly in non-cirrhotic NASH patients, are needed to reduce the future impact imposed by NASH-related HCC.

关键词： Non-alcoholic steatohepatitis Cirrhosis Non-alcoholic fatty liver disease Obesity Hepatocellular carcinoma

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Unique case of oligoastrocytoma with recurrence and grade progression:Exhibiting differential expression of high mobility group-A1 and human telomerase reverse transcriptase

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World Journal of Clinical Cases 2016年第9期4卷 296-301页

作者： Puneet Gandhi Richa khare kavita Niraj Nitin Garg sandeep k Sorte Hanni Gulwani Department of Research Bhopal Memorial Hospital and Research Centre Department of Neurosurgery Bhopal Memorial Hospital and Research Centre and Bansal Hospital Department of Pathology Bhopal Memorial Hospital and Research Centre

Mixed gliomas, primarily oligoastrocytomas, account for about 5%-10% of all gliomas. Distinguishing oligoastrocytoma based on histological features alone has limitations in predicting the exact biological behavior, necessitating ancillary markers for greater specificity. In this case report, human telomerase reverse transcriptase(hT ERT) and high mobility group-A1(HMGA1); markers of proliferation and stemness, have been quantitatively analyzed in formalin-fixed paraffin-embedded tissue samples of a 34 years old patient with oligoastrocytoma. Customized florescence-based immunohistochemistry protocol with enhanced sensitivity and specificity is used in the study. The patient presented with a history of generalized seizures and his magnetic resonance imaging scans revealed infiltrative ill-defined mass lesion with calcified foci within the left frontal white matter, suggestive of glioma. He was surgically treated at our center for four consecutive clinical events. Histopathologically, the tumor was identified as oligoastrocytoma-grade Ⅱ followed by two recurrence events and final progression to grade Ⅲ. Overall survival of the patient without adjuvant therapy was more than 9 years. Glial fibrillary acidic protein, p53, ki-67, nuclear atypia index, pre-operative neutrophillymphocyte ratio, are the other parameters assessed. Findings suggest that hT ERT and HMGA1 are linked to tumor recurrence and progression. Established markers can assist in defining precise histopathological grade in conjuction with conventional markers in clinical setup.

关键词： Human telomerase reverse transcriptase High mobility group-A1 Oligoastrocytoma Recurrence Tumor grade

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Analysis and modeling of highway truck traffic volume variations during severe winter weather conditions in Canada

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Journal of Modern Transportation 2015年第3期23卷 228-239页

作者： Hyuk-Jae Roh Satish Sharma Prasanta k.Sahu sandeep Datia City of Regina Faculty of Engineering and Applied Science University of Regina Department of Civil Engineering Birla Institute of Technology Pilani City of Edmonton

This paper investigates the impact of cold and snow on daily and hourly truck traffic volume on a primary highway in Alberta, Canada. This research is based on a detailed case study of 5 years of weigh-in-motion data recorded continuously at Leduc site on Highway 2A. Influence of the winter conditions on truck type distribution is examined by classifying trucks into single-unit trucks, single-trailer, and multi-trailer units. It is evident from the study that proportion of the three truck classes in the total truck traffic remained essentially stable over the study period （2005-2009）. Dummy-variable regression models are used to relate daily and hourly truck traffic volume with snowfall and categorized cold as independent variables. The statistical significance of all the independent variables used in the model is established by conducting tests such as R2, F test, incremental F test, and t test. The study results suggested that the truck volume is not significantly affected by the normal snowfall or the typical cold temperatures, i.e., average daily snowfall about less than 15 cm or temperatures higher than -25 ℃ are not likely to affect the truck traffic patterns. It is believed that the findings of this study can benefit highway agencies in developing programs and policies for efficient monitoring of truck traffic throughout the year and snow removal during the winter season in Canada.

关键词： Truck traffic ·Snowfall · Cold temperature ·Weather·Alberta· Canada

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Chlorination roasting-coupled water leaching process for potash recovery from waste mica scrap using dry marble sludge powder and sodium chloride

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1203-1215页

作者： sandeep kumar Jena Jogeshwar Sahu Geetikamayee Padhy Swagatika Mohanty Ajit Dash Mineral Processing and Central Characterization Department Council of Scientific and Industrial Research(CSIR)-Institute of Minerals and Materials Technology(IMMT)BhubaneswarOdisha 751013India

The present paper reports the effective utilization of marble sludge powder(MSP)for the recovery of potash values from waste mica scrap using chlorination roasting-water leaching *** studies indicated the presence of dolomite as the major mineral phase in MSP,whereas muscovite and quartz were observed in the mica *** acid leaching studies suggest a maximum of 22%potash recovery under conditions:4 M H2SO4 acid,particle size of^100μm,stirring speed of 600 r/min,leaching temperature of 75℃,and leaching time of 90 *** chlorination roasting-water leaching process was adopted to achieve the lowest level of 80%-90%potash *** optimum conditions for the recovery of^93%potash from mica(~8.6wt%k2O)requires 900℃ roasting temperature,30 min roasting time,and 1:1:0.75 mass ratio of mica:MSP:*** roasting temperature and amount of NaCl are found to be the most important factors for the recovery *** reaction mechanism suggests the formation of different mineral phases,including sylvite(kCl),wollastonite,kyanite,and enstatite,during roasting,which were confirmed by X-ray diffraction(XRD)analyses and scanning electron microscopy(SEM)*** MSP-blended NaCl additive is more effective for potash recovery compared with the other reported commercial roasting additives.

关键词： potash recovery mica scrap marble sludge powder chlorination roasting water leaching

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High-yield synthesis and liquid-exfoliation of two- dimensional belt-like hafnium disulphide

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Nano Research 2018年第1期11卷 343-353页

作者： Harneet kaur sandeep Yadav Avanish k. Srivastava Nidhi Singh Shyama Rath Jorg J. Schneider Om P. Sinha Ritu Srivastava National Physical Laboratory Council of Scientific and Industrial Research Dr. K. S. Krishnan Road New Delhi I I O012 India Academy of Scientific and Innovative Research NPL New Delhi 110012 India Technische Universitat Darmstadt Eduard-ZintMnstitut f~r Anorganische und Physikalische Chemie 12 105 117 Alarich-Weiss-Str 12 64287 Darmstadt Germany DepartmentofPhysics andAstrophysics University of Delhi Delhi 110007 India Amity Institute of Nanotechnology Amity University UP Sector 125 Noida Uttar Pradesh 201313 India

Producing environmentally stable monolayers and few-layers of hafnium disulphide （HfS2） with a high yield to reveal its unlocked electronic and optoelectronic applications is still a challenge. HfS2 is a layered two-dimensional material of group-IV transition metal dichalcogenides. For the first time, we demonstrate a simple and cost-effective method to grow layered belt-like nanocrystals of HfS2 with a notably large interlayer spacing followed by their chemical exfoliation. Various microscopic and spectroscopic techniques confirm that these as-grown crystals exfoliate into single or multiple layers in a few minutes using solvent assisted ultrasonification method in N-cyclohexyl-2- pyrrolidone. The exfoliated nanosheets of HfS2 exhibit an indirect bandgap of 1.3 eV with high stability against surface degradation. Furthermore, we demonstrate that these nanosheets hold potential for electronic applications by fabricating a field-effect transistor based on few-layered HfS2, exhibiting a field-effect mobility of 0.95 cm2/（V.s） with a high on/off current modulation ratio of 10,000 in ambient conditions. The method is scalable and has a potential significance for both academic and industrial purposes.

关键词： two-dimensionalmaterials hafnium disulphide nano-crystals liquid-phase exfoliation environment-stabili~ field-effect transistor

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Band-gap engineering of La1-xNdxAlO3(x = 0,0.25,0.50,0.75,1)perovskite using density functional theory：A modified Becke Johnson potential study

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Chinese Physics B 2016年第6期25卷 376-382页

作者： sandeep D P Rai A Shankar M P Ghimire Anup Pradhan Sakhya T P Sinha R khenata S Bin Omran R k Thapa Department of Physics Mizoram University Aizawl-796004 India Department of Physics Pachhunga University College Aizawl-796001 India Department of Physics University of North Bengal Darjeeling-734013 India IFW Dresden e. V. P. O. Box 270116 D-01171 Dresden Germany Department of Physics Bose Institute 93/1 Acharya Prafulla Chandra Road Kolkata 700009 India Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M) Department de Technologie Universite de Mascara 29000 Mascara Algerie Algeria Department of Physics and Astronomy College of Science King Saud University P. O: Box 2455 Riyadh 11451 Saudi Arabia

The structural,electronic,and magnetic properties of the Nd-doped Rare earth aluminate,La1-xNdxAlO3（x = 0%to 100%） alloys are studied using the full potential linearized augmented plane wave（FP-LAPW） method within the density functional *** effects of the Nd substitution in La AlO3 are studied using the supercell *** computed electronic structure with the modified Becke–Johnson（m BJ） potential based approximation indicates that the La1-xNdxAlO3 alloys may possess half-metallic（HM） behaviors when doped with Nd of a finite density of states at the Fermi level（EF）.The direct and indirect band gaps are studied each as a function of x which is the concentration of Nddoped La *** calculated magnetic moments in the La1-xNdxAlO3 alloys are found to arise mainly from the Nd-4f state.A probable half-metallic nature is suggested for each of these systems with supportive integral magnetic moments and highly spin-polarized electronic structures in these doped systems at *** observed decrease of the band gap with the increase in the concentration of Nd doping in La AlO3 is a suitable technique for harnessing useful spintronic and magnetic devices.

关键词： density functional theory rare earth aluminates perovskites electronic structures

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Dynamic Identity Based Authentication Protocol for Two-Server Architecture

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Journal of Information Security 2012年第4期3卷 326-334页

作者： sandeep k. Sood Department of Computer Science & Engineering Regional Campus Gurdaspur Gurdaspur India

Most of the password based authentication protocols make use of the single authentication server for user's authentication. User's verifier information stored on the single server is a main point of susceptibility and remains an attractive target for the attacker. On the other hand, multi-server architecture based authentication protocols make it difficult for the attacker to find out any significant authentication information related to the legitimate users. In 2009, Liao and Wang proposed a dynamic identity based remote user authentication protocol for multi-server environment. However, we found that Liao and Wang's protocol is susceptible to malicious server attack and malicious user attack. This paper presents a novel dynamic identity based authentication protocol for multi-server architecture using smart cards that resolves the aforementioned flaws, while keeping the merits of Liao and Wang's protocol. It uses two-server paradigm by imposing different levels of trust upon the two servers and the user's verifier information is distributed between these two servers known as the service provider server and the control server. The proposed protocol is practical and computational efficient because only nonce, one-way hash function and XOR operations are used in its implementation. It provides a secure method to change the user's password without the server's help. In e-commerce, the number of servers providing the services to the user is usually more than one and hence secure authentication protocols for multi-server environment are required.

关键词： Authentication Protocol Smart Card Dynamic Identity Multi-Server Architecture Password

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Targeting infections and inflammation through micro and nano-nutraceuticals

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Food Bioscience 2022年第5期49卷 50-67页

作者： Fabiana Helen Santos sandeep k.Panda Danielle Cristine Mota Ferreira Gargi Dey Gustavo Molina Franciele Maria Pelissari Laboratory of Green Materials Institute of Science and TechnologyFederal University of Jequitinhonha and Mucuri ValleysCEP 39100-000DiamantinaMGBrazil Department of Food Technology School of Food EngineeringUniversity of CampinasMonteiro Lobato80CEP 13083-862CampinasSPBrazil School of Biotechnology Campus 11KIIT UniversityBhubaneswar751024India Laboratory of Food Materials Studies Department of Food TechnologyUniversity of ViçosaCEP 36570-900ViçosaMinas GeraisBrazil Laboratory of Food Biotechnology Institute of Science and TechnologyFederal University of Jequitinhonha and Mucuri ValleysCEP 39100-000DiamantinaMGBrazil

Nowadays,the pharma and food industries have been gearing up to meet the urgent need for anti-infective and anti-inflammatory nutritional *** this way,several nutraceutical compounds are being re-evaluated due to their established *** compounds have been or may be efficiently targeted against infections,inflammatory conditions and for immune ***,for successful management of these metabolic conditions,the nutraceuticals need to be designed into effective nutritional *** recent years there have been tremendous progress in the re-engineering of structurally delivery vehicles which provide stability,enhance bioaccessibility and bioavailability of these *** this perspective,this review focuses on the structural and functional aspects of several such bio-based delivery vehicles like the micro and nano particles,nano-emulsions and liposome-based *** aim is to bring forth recent information on the efficacious nutraceuticals and the suitable delivery vehicles which would be useful against infections and inflammatory conditions.

关键词： Bioactive compounds Bioavailability Probiotics Delivery systems Nanotechnology Infection diseases

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Early Paleozoic basement diorite of arc-magmatism from kutch basin, Western India

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Acta Geochimica 2024年第2期43卷 296-307页

作者： Piyush Gupta sandeep Singh Shakti Singh Rathore Argha Narayan Sarkar Geochronology Laboratory KDMIPEOil and Natural Gas Corporation Ltd.9Kaulagarh RoadDehradun 248195India Department of Earth Sciences Indian Institute of TechnologyRoorkee 247667India

In this study,we report for theﬁrst time an Early Palaeozoic basement diorite from the drilled well Nirona-A in the Banni Half-Graben of the kutch basin,western *** 40Ar–39Ar dates provided a plateau age of 441.84±2.66 Ma and another pseudo plateau of 441.28±5.82 to 388.08±16.65 Ma for the basement *** ages constrain the basement formation age to the Late Ordovician-Early Silurian *** obtained basement ages are correlatable with the later part of Cambro-Ordovician alkaline magmatism that has been reported from the Huqf area in Central Oman,whereas their lithological and petrographic correlativity with base-ment diorites occurring in the Dinsi Body of Nagar Parkar igneous complex in Pakistan can also be *** geochemical studies characterized the diorite with enrich-ment of LILE(Rb,Ba,and k)and LREE(La,Ce,Nd),strong depletion of HFSE(Nb,Sr,P,and Ti),along with weakly negative Eu *** geochemical signatures indicate their petrogenetic afﬁliation with mantle-derived magmas,as well as their tectonic setting to be arc-related,having post-collisional continental-arc type afﬁ****440 Ma basement of kutch,therefore,appears to rep-resent the later thermal event associated with the reworked Neoproterozoic subduction-related suite from Greater India’s northwest edge,which has implications for Gond-wana assembly in the northwest Indian subcontinent.

关键词： kutch basin 40Ar–39Ar ages Early palaeozoic basement Continental-arc magmatism Calc-alkaline magmatism

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