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Optimizing calcination of coal by-products for maximizing REE leaching recovery and minimizing Al,Ca,and Fe contamination

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Journal of Rare Earths 2024年第7期42卷 1354-1365,I0006页

作者： Tushar gupta Ahmad Nawab Rick Honaker MP Materials Mountain Pass Mine 67750 Bailey RoadMountain PassCA92366USA Department of Mining Engineering University of KentuckyLexingtonKY40506USA

High-temperature calcination is effective in improving the leaching characteristics of rare earth elements(REEs)from conventional REE-bearing minerals by transforming them into more leachable ***,the recovery of contaminants such as Al,Fe,and Ca also increases *** objective of the study was to maximize the REE extraction while minimizing the concentration of contaminant ions(Al,Ca,and Fe)in the leach *** density fractions of the coarse refuse from the Baker and Fire Clay seam coal refuse were pulverized to a top size of 180μm and used as a feedstock for the *** the samples generated from thermal treatment were leached at 1%(w/v)using 1.2 mol/L sulfuric acid at 75℃ for 2 *** results from a parametric program based on a Box-Behnken design were used for modeling and optimization of three operating parameters associated with the lab-scale calcination *** parameters included temperature(400-800℃),ramp rate(2-10℃/min)and holding time(0-120 min).It was determined that the calcination temperature was the most significant parameter influencing REE *** majority of the heavy rare earth elements(HREEs)were found to be present in an insoluble form in the calcination products and were marginally affected by thermal treatment.A strong correlation between light rare earth elements recovery(LREEs)and Al suggested a possible association with *** optimum operating conditions for high REE recovery with comparatively lower contaminant concentration for 1.6 specific gravity float and 2.2 sink fractions of Baker and Fire Clay seam material were determined to be at 776,800℃ and 407,800℃,calcining temperatures,respectively.A higher optimum temperature of 1.6 float fraction of Baker seam relative to Fire Clay seam material was due to elevated pyrite concentration in Baker seam *** treatment at 400℃ converted pyrite into a soluble intermedium iron oxide,resulting in a high Fe content in the ***

关键词： Calcination Optimization Rare earth elements Coal refuse

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A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light

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Journal of Transportation Technologies 2024年第1期14卷 82-87页

作者： Pranav gupta Silki Arora Drive Safe Now Ottawa Canada

Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the u.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada, during 2019, the National Collision Database shows that 28% of traffic fatalities and 42% of serious injuries occurred at intersections. Likewise, the u.S. National Highway Traffic Administration (NHTSA) found that about 40% of the estimated 5,811,000 accidents in the u.S. during the year studied were intersection-related crashes. In fact, a major survey by the car insurance industry found that nearly 85% of drivers could not identify the correct action to take when approaching a yellow traffic light at an intersection. One major reason for these accidents is the “yellow light dilemma,” the ambiguous situation where a driver should stop or proceed forward when unexpectedly faced with a yellow light. This situation is even further exacerbated by the tendency of aggressive drivers to inappropriately speed up on the yellow just to get through the traffic light. A survey of Canadian drivers conducted by the Traffic Injury Research Foundation found that 9% of drivers admitted to speeding up to get through a traffic light. Another reason for these accidents is the increased danger of making a left-hand turn on yellow. According to the National Highway Traffic Safety Association (NHTSA), left turns occur in approximately 22.2% of collisions—as opposed to just 1.2% for right turns. Moreover, a study by CNN found left turns are three times as likely to kill pedestrians than right turns. The reason left turns are so much more likely to cause an accident is because they take a driver against traffic and in the path of oncoming cars. Additionally, most of these left turns occur at the driver’s discretion—as opposed to the distressingly brief left-hand arrow at busy intersections. Drive Safe Now proposes a workable solution for reducing the number of accidents occ

关键词： Traffic Accidents Yellow Light Traffic Light Signals Intersection Crashes Collision Traffic Fatalities Traffic Injuries Vehicles Safety Speed Limit Driving Pedestrians Bicyclists Motorcyclists Caution Line Yellow Light Dilemma Left Hand Turn on Yellow Distance Smart Road Technology Signs Signage Autonomous Vehicles AVs Road Safety IoT Internet of Things Infrastructure Accident Reduction Driving Habits Stop Line Red Light Jumping Pedestrian Safety Caution Light Stopping at Intersection Safety at Intersections

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Sources and Deficiency Diseases of Mineral Nutrients in Human Health and Nutrition:A Review

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Pedosphere 2014年第1期24卷 13-38页

作者： u.C.gupta S.C.gupta Agriculture and Agri-Canada Canada Crops and Livestock Research Centre The Department of Plastic Surgery Loma Linda University

Mineral nutrients are fundamentally metals and other inorganic compounds. The life cycle of these mineral nutrients begins in soil, their primary source. Soil provides minerals to plants and through the plants the minerals go to animals and humans; animal products are also the source of mineral nutrients for humans. Plant foods contain almost all of the mineral nutrients established as essential for human nutrition. They provide much of our skeletal structure, e.g., bones and teeth. They are critical to countless body processes by serving as essential co-factors for a number of enzymes. Humans can not utilize most foods without critical minerals and enzymes responsible for digestion and absorption. Though mineral nutrients are essential nutrients, the body requires them in small, precise amounts. We require them in the form found in crops and they can be classified into three different categories： major, secondary, and micro or trace minerals. This classification is based upon their requirement rather than on their relative importance. Major minerals such as potassium （K） and phosphorus （P） are required in amounts of up to 10 g d-1. The daily requirement of secondary and micro minerals ranges from 400 to 1 500 mg d-1 and 45 ~tg d-1 to 11 mg d-1, respectively. To protect humans from mineral nutrient deficiencies, the key is to consume a variety of foods in modest quantities, such as different whole grains, low fat dairy, and different meats, vegetables and fruits. For insurance purposes, a supplement containing various mineral nutrients can be taken daily.

关键词： deficiency diseases deficiency symptoms origin recommended daily dose toxicity

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Instability of binary nanofluids with magnetic field

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Applied Mathematics and Mechanics(English Edition) 2015年第6期36卷 693-706页

作者： u.gupta J.SHARMA V.SHARMA Dr.S.S.Bhatnagar university Institute of Chemical Engineering and Technology Panjab University Energy Research Centre Panjab University Department of Mathematics Himachal Pradesh University

The present paper investigates the effects of a vertical magnetic field on the double diffusive nanofluid convection, The effects of the Brownian motion and ther- mophoresis due to the presence of nanoparticles and the effects of the Dufour and Sorer parameters due to the presence of solute are included in the investigated model. The normal mode technique is used to solve the conservation equations. For the analytical study, valid approximations are made in the complex expression for the Rayleigh number to get useful and interesting results. The bottom heavy binary nanofluids are more stable than the regular binary fluids, while the top heavy binary nanofluids are less stable than the regular binary fluids. The critical wave number and the critical Rayleigh number in- crease whereas the frequency of oscillation （for the bottom heavy configuration） decreases when the Chandrasekhar number increases. The numerical results for the alumina-water nanofiuid are studied by use of the MATHEMATICA software.

关键词： natural convection binary nanofluid Brownian motion thermophoresis,Chandrasekhar number

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Guinea pig model of tuberculosis

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Asian Pacific Journal of Tropical Medicine 2009年第2期2卷 76-80页

作者： Pushpa gupta u.D.gupta Experimental Animal Facility National JALMA Institute for Leprosy & Other Mycobacterial DiseasesTajganjAgra 282001India

Animal models are being developed for testing different vaccine candidates as well as testing of new antitubercular since a long ***,guinea pigs and rabbits are animals which are frequently *** each model has got its merits as well as demerits and each of them differ from human tuberculosis in one aspect or the other but none of the model completely mimics the human *** of the different animal species, guinea pig model is one of the better models as it is very sensitive to *** infection but it has certain limitations like paucity of immunological ***,it is the best model for tuberculosis research.

关键词： Vaccines Animal Models Tuberculosis Guinea pig

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Spark plasma sintering of a high-energy ball milled Mg-10 wt% Al alloy

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Journal of Magnesium and Alloys 2020年第2期8卷 319-328页

作者： M.u.F.Khan A.Patil J.Christudasjustus T.Borkar R.K.gupta Department of Chemical Biomolecularand Corrosion EngineeringThe University of AkronAkronOH 44325United States Department of Mechanical Engineering Washkevicz College of EngineeringCleveland State UniversityClevelandOH 44115United States

The influence of spark plasma sintering(SPS)temperature on microstructure,hardness and corrosion behavior of a high-energy ball milled Mg-10wt%Al alloy was investigated in this *** holding time and sintering pressure for SPS were kept constant while varying the sintering temperature from 200 to 350℃.The grain size and microstructure were studied using X-ray diffraction analysis,scanning electron microscopy,energy dispersive X-ray spectroscopy,and Archimedes'based density *** behavior was investigated using potentiodynamic polarization *** nanocrystalline regime(grain sizeup to 350℃.The density of the alloy increased with increasing the SPS ***'hardness and corrosion performance improved up to 300℃ followed by a decrease after SPS at 350℃.Possible reasons for densification,strengthening,and corrosion behavior have been discussed in the light of reduced porosity and microstructural changes.

关键词： Nanocrystalline alloy Magnesium High energy ball milling Spark plasma sintering Corrosion

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Optimization of Trans.ucer Location for Novel Non-Intrusive Methodologies of Diagnosis in Diesel Engines

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Sound & Vibration 2021年第3期55卷 221-234页

作者： S.Narayan M.u.Kaisan Shitu Abubakar Faisal O.Mahroogi Vipul gupta Department of Mechanical Engineering Qassim UniversityBuraydah51452Saudi Arabia Department of Mechanical Engineering Ahmadu Bello UniversityZaria810211Nigeria Department of Mechanical Engineering Islamic University of MadinaMedina42351Saudi Arabia Department of Mechanical Engineering Indus International UniversityUna174301India

The health monitoring has been studied to ensure integrity of design of engine structure by detection,quantification,and prediction of *** detection of faults may allow the downtime of maintenance to be rescheduled,thus preventing sudden shutdown of *** cylinder pressure developed,vibrations and noise emissions data provide a rich source of information about condition of *** of vibrations and noise emissions are novel non-intrusive methodologies for which positioning of various trans.ucers are important *** presented work shows applicability of these diagnosis methodologies adopted in case of diesel *** effects of changing various fuel injection parameters was *** of using non-intrusive technique has been analyzed by changing locations of *** of this worklies in exploring signal processing methods for various locations around the engine test set *** frequency ranges of contributing noise and vibration sources were ***-Frequency analysis showed the onset of various *** on the identification of various frequency bands,it is possible to device suitable filters in order to extract more information.

关键词： IC engines automotive vibrations and noise emissions condition monitoring specialized industrial machinery and equipment

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Effect of arbuscular mycorrhizal fungi on growth of Gmelina arborea in arsenic-contaminated soil

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Journal of Forestry Research 2010年第4期21卷 423-432,522页

作者： A.Barua S.D.gupta M.A.u.Mridha M.K.Bhuiyan Institute of Forestry and Environmental Sciences University of Chittagong School of Environment Natural Resources and GeographyBangor University Department of Botany University of Chittagong

Arsenic （As） in the soils of South-Eastern Bangladesh is not rely a threat for the health of millions of people but also a problem for plant growth due to its higher concentration in soil. Gmelina arborea Linn. is a promising fast growing tree species in Bangladesh which has dso a potential to be planted in arsenic contaminated areas. This study tssessed the role of arbuscular mycorrhizal （AM） fungi on the growth of 7. arborea in arsenic amended soils at nursery stage. Before sowing ;eeds, soils were treated with four different concentrations （10 ***^-1, 25 ***^-1, 50 ***^-1, and 100 ***^-1） of Arsenic. Growth parameters length of shoot and root, collar diameter, fresh and dry weight of shoot and root） of the plant, and mycorrhizal root colonization and spore population in the rhizosphere soil of G. arborea were recorded. Mycorrhizal seedlings showed better growth than non-mycorrhizal eedlings. Myeorrhizal seedlings planted in soil with ***^-1 arsenic howed best performance in terms of growth, biomass and mycorrhizal ：olonization, compared to other treatments with higher concentration of Lrsenie. With increasing arsenic concentration, growth of seedlings, nycorrhizal infection rate and spore population, all decreased ignificantly （p〈0.05）. The mycorrhizal seedlings had as much as 40% higher increment in total growth and 2.4 times higher increment in biomass compared to non-mycorrhizal seedlings. The study clearly indicated that mycorrhizal inoculation could reduce the harmful effects of arsenic on the initial growth of G. arborea Linn. in degraded soil at nursery stage.

关键词： arsenic arbuscular mycorrhizal fungi Gmelina arborea Linn. bioremediation plant growth

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Multi-criteria decision based geospatial mapping of flood susceptibility and temporal hydro-geomorphic changes in the Subarnarekha basin, India

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Geoscience Frontiers 2021年第5期12卷 327-341页

作者： Sumit Das Amitesh gupta Department of Geography Savitribai Phule Pune UniversityPune 411007India Marine and Atmospheric Science Department Indian Institute of Remote Sensing(ISRO)DehradunIndia Department of Remote Sensing and GIS JIS UniversityKolkataIndia

The Subarnarekha River in east India experiences frequent high magnitude flooding in monsoon *** this study,we present an in-depth analysis of flood hydrology and GIS-based flood susceptibility mapping of the entire *** 40 years of annual peak discharge data,historical cross-sections of different gauging sites,and 12 flood conditioning factors were *** flood susceptibility mapping followed an expert knowledge-based multi-parametric analytical hierarchy process(AHP)and optimized AHP-VIP *** hydrology data indicated more than 5 times higher discharge contrasted with the mean streamflow of the peak monsoon month in all hydro-monitoring stations that correspond to possible overbank flooding in the shallow semi-alluvial reaches of the Subarnarekha *** ratio revealed continuous changes on the channel cross-sections at decadal scale in all gauging *** flood susceptibility map through optimized AHP-VIP method showed a great amount of areas(38%)have a high probability of flooding and demands earnest attention of administrative *** AHP-VIP based flood susceptibility map was theoritically validated through AuC approach and it showed fairly high accuracy(AuC=0.93).Our study offers an exceptionally cost and time effective solution to the flooding issues in the Subarnarekha basin.

关键词： Flood susceptibility AHP GIS Discharge Subarnarekha India

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Role of salivary matrix metalloproteinase-8 （MMP-8） in chronic periodontitis diagnosis

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Frontiers of Medicine 2015年第1期9卷 72-76页

作者： Namita gupta N.D. gupta Akash gupta Saif Khan Neha Bansa Department of Periodontics and Community Dentistry Dr. Z. A. Dental College Aligarh Muslim University Aligarh U.P. India Department of Biochemistry Rama Medical College and Hospital Pilakhua Hapur. U.P. India

Periodontitis is an inflammatory disease of the periodontium. Any imbalance between the matrix metalloproteinases （MMPs） secreted by neutrophils and tissue inhibitors initiates the destruction of collagen in gum tissue, leading to chronic periodontitis. This study aimed to correlate salivary levels of MMP-8 and periodontal parameters of chronic periodontitis to establish MMP-8 as a noninvasive marker for the early diagnosis of chronic periodontitis. The study involved 40 subjects visiting the periodontic OPD of Dr. Ziauddin Ahmad Dental College and Hospital, located in Aligarh, u.P., India, from 2011 to 2012. The subjects were divided into two groups： group I consisted of 20 periodontally healthy subjects （controls） while group II consisted of 20 patients with chronic periodontitis. Chronic periodontitis was assessed on the basis of several periodontal parameters, including pocket probing depth （PPD）, clinical attachment level （CAL）, gingival index （GI）, and plaque index （PI）. Around 3 ml of unstimulated and whole expectorated saliva was collected for MMP-8 estimation by ELISA using Quantikine human total MMP-8 immunoassay kits. Data were analyzed using STATISTICA （Windows version 6） software. Salivary MMP-8 levels of groups I and II were 190.91 ± 143.89 ng/ml and 348.26± 202.1 ng/ml, respectively. The MMP-8 levels and periodontal status （PPD, CAL, GI, and PI） of groups I and II showed positive and significant correlations （for PPD, r = 0.63, P 〈 0.001; for CAL, r = 0.54, P 〈 0.001; for GI, r = 0.49, P 〈 0.001; and for PI, r = 0.63, P 〈 0.001）. The results of this study demonstrate elevated concentrations of MMP-8 in individuals with chronic periodontitis.

关键词： matrix metalloproteinase-8 chronic periodontitis pocket probing depth clinical attachment level gingival index plaque index

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