检索结果-南通市图书馆

Journal of central South University 2015年第9期22卷 3302-3310页

作者： Jagannath Pal Satadal ghorai Bikash Nandi Tapas chakraborty goutam das T.Venugopalan cSIR-National Metallurgical Laboratory Tata Steel

Pelletization of hematite ore requires high fineness and very high induration temperature（~1325 ℃） owing to its poor diffusion bonding unlike magnetite ore. Further, high-alumina hematite pellets show very high reduction degradation index（RDI） during low temperature（500-650 ℃） reduction due to their volume expansion and lattice distortion. Noamundi（India） hematite ore contains very high Al2O3（2.3%） with adverse ratio of alumina to silica（~2） for which, it shows very high RDI. In this work, the acid pellets prepared from Noamundi ore fines of optimum Blaine fineness show good cold crushing strength（ccS）. However, it shows very high RDI（77%）. In order to reduce RDI, Mg O in form of two different gangue-containing fluxes, such as pyroxenite and olivine in varying quantities has been added. The optimum requirement and performance of these fluxes has been examined and compared. Both pyroxenite and olivine fluxed pellets show significant lowering of RDI（26% and 23%, respectively） and improvement of other properties, viz ccS, swelling indices etc with good reducibility（70%-77%）. Finally, a good quality acidic hematite pellet was developed from high-alumina ore without using any lime which is very important charge material in combination of basic sinter in blast furnace.

关键词： hematite pellet high-alumina ore reduction degradation index(RDI) pyroxenite flux olivine flux effect of MgO

The Influence of cobalt Acetate on Sol-gel Derived Mullite Densification Behaviour

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2012年第5期27卷 836-840页

作者： Debasis Roy Biswajoy Bagchi Alakananda Bhattacharya Sukhen das Papiya Nandy Physics Department Jadavpur University

Monophasic mullite （3Al2O3？2SiO2） samples doped with 0.002 M, 0.02 M, 0.1 M, 0.15 M and 0.2 M of cobalt were prepared by a sol-gel process. Prepared gels were then dried, grinded, pressed into pellets and sintered at 1 000 °c and 1 300 °c for 4 h. Phase formation and densification behavior has been investigated as a function of the cobalt content and sintering temperature. Mullite densification behavior was analyzed .The density of the sintered ceramics was measured using Archimedes method. coO and co related compounds were detected by the analysis for g3, g4 and g5 doping levels. The mullite X-ray diffraction suggests predominant incorporation of co in the glassy phase, whose quantity increased with the doping level.

关键词： sol-gel processes nanocomposite XRD FESEM mullite

Anti-viral role of toll like receptor 4 in hepatitis B virus infection: An in vitro study

在线全文

学校读者我要写书评

暂无评论

World Journal of gastroenterology 2016年第47期22卷 10341-10352页

作者： Dipanwita das Neelakshi Sarkar Isha Sengupta Ananya Pal Debraj Saha Manikankana Bandopadhyay chandrima das Jimmy Narayan Shivram Prasad Singh Runu chakravarty IcMR Virus Unit Kolkata ID and BG Hospital Campus Biophysics and Structural genomics Division Saha Institute of Nuclear Physics Department of gastroenterology SCB Medical College Kalinga gastroenterology Foundation Beam Diagnostics Premises

AIM Toll like receptors plays a significant anti-viral role in different infections. The aim of this study was to look into the role of toll like receptor 4(TLR4) in hepatitis B virus(HBV) *** Real time PcR was used to analyze the transcription of TLR4 signaling molecules, cell cycle regulators and HBV DNA viral load after triggering the Hep g2.2.15 cells with TLR4 specific ligand. Nuclear factor(NF)-κB translocation on TLR4 activation was analyzed using microscopic techniques. Protein and cell cycle analysis was done using Western Blot and FAcS *** The present study shows that TLR4 activation represses HBV infection. As a result of HBV suppression, there are several changes in host factors which include partial release in g1/S cell cycle arrest and changes in host epigenetic marks. Finally, it was observed that anti-viral action of TLR4 takes place through the NF-κB *** The study shows that TLR4 activation in HBV infection brings about changes in hepatocyte microenvironment and can be used for developing a promising therapeutic target in future.

关键词： Hepatitis B virus Toll like receptor 4 cell cycle Epigenetic marks Innate immune response

Multifunctional hopeite nanocoating on Ti64 substrates by pulsed laser deposition and radio frequency magnetron sputtering for orthopedic implant applications:A comparative study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of central South University 2020年第8期27卷 2198-2209页

作者： Ashish das Mukul SHUKLA Department of Mechanical Engineering Motilal Nehru National Institute of TechnologyAllahabad 211004India Department of Production and Industrial Engineering National Institute of TechnologyJamshedpur 831014India School of Mechanical and Aerospace Engineering Queen’s UniversityBelfast BT71NNUnited Kingdom Department of Mechanical Engineering Technology University of JohannesburgJohannesburg PO Box 524South Africa

Functionalized implants demonstrate an upgraded approach in orthopedic implants,aiming to achieve long term success through improved bio *** coatings with multifunctionality have arisen as an effective substitute for conventional coatings,owing to their combination of various properties that are essential for bio-implants,such as osteointegration and antibacterial *** the present study,thin hopeite coatings were produced by Pulsed laser deposition(PLD)and radio frequency magnetron sputtering(RFMS)on Ti64 *** obtained hopeite coatings were annealed at 500°c in ambient air and studied in terms of surface morphology,phase composition,surface roughness,adhesion strength,antibacterial efficacy,apatite forming ability,and surface wettability by scanning electron microscope(SEM),X-ray diffraction(XRD),atomic force microscope(AFM),tensometer,fluorescence-activated cell sorting(FAcS),simulated body fluid(SBF)immersion test and contact angle goniometer,***,based on promising results obtained in the present work it can be summarized that the new generation multifunctional hopeite coating synthesized by two alternative new process routes of PLD and RFMS on Ti64 substrates,provides effective alternatives to conventional coatings,largely attributed to strong osteointegration and antibacterial character of deposited hopeite coating ensuring the overall stability of metallic orthopedic implants.

关键词： hopeite Ti64 alloy pulsed laser deposition magnetron sputtering coating implant

computer Aided Design and Performance Analysis of Inverse Fluidized Bed Biofilm Reactors with Special Reference to Bioplastic Synthesis

在线全文

学校读者我要写书评

暂无评论

Advances in chemical Engineering and Science 2016年第2期6卷 130-139页

作者： c. M. Narayanan Shrijita das Department of chemical Engineering National Institute of Technology Durgapur India

Poly Laevo Lactic Acid (PLLA), in spite of being an excellent bioplastic, has exorbitantly high market price due to the high cost of raw material (lactose, glucose, sucrose). Hence, its manufacture is being attempted starting from waste effluents such as cheese whey and molasses. Earlier studies on the same in fluidized bed and semifluidized bed biofilm reactors yielded encouraging results. The present study therefore involves design and analysis of inverse fluidized bed biofilm reactors for lactic acid synthesis. The performance features of the bioreactor have been studied both mathematically as well as experimentally. The inverse fluidized bed biofilm reactor has been found to provide more than 75% conversion of sucrose/lactose even at high capacities (high feed flow rates) exceeding 56,000 L/hr, within a reasonably low reactor volume. The fractional substrate conversion increases, though sluggishly, with increase in feed flow rate due to bed expansion and also with increase in cell mass concentration in biofilm due to enhancement in intrinsic rate of bioconversion. The inverse fluidized bed biofilm reactor of proposed design could be safely recommended for the commercial synthesis of polymer grade lactic acid from waste effluents such as cheese whey and molasses. The low operating cost of the bioreactor (due to downflow mode of operation) enhances the economy of the process. This would also help in significantly lowering the market price of the green plastic (PLLA) and shall promote its large scale manufacture and utilisation.

关键词： Inverse Fluidized Bed Biofilm Reactors computer Aided Design Bioplastics Lactic Acid Synthesis Software Development

Autotrophic potential in mesophilic heterotrophic bacterial isolates from Sino-Pacific marine sediments

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2017年第2期36卷 69-77页

作者： cAO Wenrui das Anindita SAREN gaowa JIANg Mingyu ZHANg Hongjie YU Xinke Key laboratory of Marine geology and Environment (MAgE) Institute of Oceanology Chinese Academy of Sciences (IO-CAS) Qingdao 266071 China Institute of Biophysics Chinese Academy of Sciences (IBP-CAS) Beijing 100101 China council of Scientific and Industrial Research (cSIR) National Institute of Oceanography Dona Paula Panaji 403004 India Maharashtra Association for the cultivation of Science (MAcS) Agharkar Research Institute Pune 411004 India

Microbial carbon fixation is a paramount process in the ocean especially below the photic zone both in water and sedimentary ecosystems. Autotrophic microbes that fix carbon dioxide are renowned. However, the question whether heterotrophs can also fix carbon is intriguing. Ten heterotrophically grown, identified bacterial isolates from the Sino-Pacific marine sediments were tested for autotrophic uptake potential with and without addition of electron donors. Nine of the ten isolates showed carbon uptake capacity without addition of any substrate at very low rates in the order of 10^（-8） to 10^（-4） fmol/（cell·h）. The addition of manganese and ammonium at 1 mmol/L final concentration enhanced the uptake potential. Addition of 1 mmol/L final concentrations of reduced iron（10^（-6） to10^（-5） fmol/（cell·h） and sulfide（10^（-5） fmol/（cell·h） decreased the uptake potential significantly at p〈0.1. Bacterial tolerance to formaldehyde suggested propensities of anaplerotic chemical reactions that form metabolic intermediates of c-1 metabolism pathways. The isolates displayed high metabolic flexibility. With the changes in electron donors, the isolates metabolically toggled between relatively anoxic reductive iron/sulfur cycles and the oxidative cycles of manganese/ammonium and vice-versa. This property makes these microbes successful survivors in the highly dynamic Sino-Pacific sediments.

关键词： autotrophy bacteria mesophiles heterotrophs Sino-Pacific

Development and evaluation of robust tree biomass equations for rubber tree (Hevea brasiliensis) plantations in India

在线全文

学校读者我要写书评

暂无评论

Forest Ecosystems 2017年第3期4卷 241-250页

作者： Biplab Brahma gudeta W.Sileshi Arun Jyoti Nath Ashesh Kumar das Department of Ecology and Environmental Science Assam University

Background： In India, rubber（Hevea brasiliensis） plantations cover -0.8 million ha of land, emphasizing its significant role in the Earth＇s carbon dynamics. Therefore, it is important to estimate the biomass stocks of plantations precisely in the context of carbon management. Previous studies in India have focused on development of allometric equations for estimating aboveground biomass（AgB） through harvesting younger trees（up to 14 yr）only or on studies with small sample sizes without assessing model bias. The objective of this study was to develop biomass estimation models for different tree components in rubber plantations and assess model predictive performance at the stand ***： A total of 67 trees were harvested from plantations of different ages（6, 15, 27 and 34 yr） in North East India and their diameter at 200 cm（D）, height and dry weights of different tree components were recorded. The data were used for evaluation of H-D and biomass estimation models at the stand ***： The Michaelis-Menten function was found to be the most appropriate model for estimating tree height among 10 commonly used H-D models. For estimation of AgB and coarse root biomass, a model that involves tree volume（i.e. D2 H） was found to provide better prediction than either D or H alone or a model that combines H, D and stand density. The estimated AgB varied from 28 Mg·ha-（-1） in 6 yr. old plantation to 169 Mg·ha-（-1） in 34 yr. old *** coarse root biomass was estimated at 4 Mg·ha-（-1） for 6 yr. old plantation and 12 Mg·ha-（-1） for 34 yr. old ***： It is concluded that models involving tree volume are more appropriate for regional level biomass estimation than simple power-law models for individual stands. We recommend that the power-law model should not be used for estimation of AgB in plantations at different growth stages because power-law parameters can be biased due to data truncation.

关键词： Aboveground biomass Data truncation Michaelis-Menten function Power-law

Antioxidants in Food and chronic Degenerative Diseases

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 1996年第2期9卷 117-123页

作者： J．K．cANDLISH N．P．das BiochemistryDepartment NationalUniversityofSingaporeKentRidgeCrescentSingapore0511 BiochemistryDepa

Both preventive and chain breaking antioxidants have a role in the limitation of free radical damage. Some of these may be regarded as 'classical', like vitamins E and c but others are more recently discovered, such as the flavonoids, widespread in plant tissues, and the muscle constituents anserine and carnosine. The major conditions in which the role of antioxidants is under intense investigation include coronary artery disease, cancer and diabetes. There are theoretical underpinnings for the efficacy of antioxidants in each of these, with the protection of low density lipoprotein (in respect of the first) being exceptionally *** attention is now being focussed on the flavonoids, which are surprisingly pleiotropic in their effects. For one of them, quercetin, over a dozen seemingly independent biologica1 effects can be listed, including the inhibition of low density lipoprotein *** also inhibit peroxidation in foodstuffs, as opposed to *** is much controversy over antioxidant supplementation policies, some authorities recommending a massive programme of supplementation for all ages and classes, others stressing the value of the traditional mixed diet. This matter is unlikely to be resolved soon,but in the meantime sensible supplementation policies should be continued for those most vulnerable, that is, babies and the aged

关键词：

On A New Arithmetic Function

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Mathematics and System Science 2017年第4期7卷 118-125页

作者： P. das K.c. chowdhury Department of Mathematics Cotton Colleges state University Gwahati 71001 India Department of Mathematics Gauhati University Guwahati- 781014 India

Here we explore some fundamental aspects of what may be termed as a new arithmetic function （defined notionally as theT function） together with its possible inverse （TI）, as it is not in frequent discussion among ... 详细信息

关键词： Arithmetic function, Pascal triangle, digital multiplicative, additive, k-additive, encryption, decryption

Potential of conservation tillage and altered land configuration to improve soil properties,carbon sequestration and productivity of maize based cropping system in eastern Himalayas,India

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Soil and Water conservation Research 2021年第2期9卷 279-290页

作者： gulab Singh Yadav Anup das Subhash Babu Kamal Prasad Mohapatra Rattan Lal Dipjyoti Rajkhowa Indian council of Agricultural Research(IcAR) Research Complex for North Eastern HillRegionTripura CentreTripuraIndia IcAR eIndian Agricultural Research Institute New DelhiIndia IcAR-National Bureau of Plant genetic Resources New DelhiIndia carbon Management and Sequestration center Ohio State UniversityColumbusUSA IcAR Research complex for NEH Region Nagaland CentreNagalandIndia

Poor soil properties especially low soil organic carbon(SOc)and nutrient and water retention capacities are major concern for sustainable agriculture in *** experiments were conducted to assess the effects of six combinations of tillage[conventional tillage(cT)and no-till(NT)]and land configurations[flat bed planting(FB),ridge and furrow planting(RF),and raised bed planting(RB)]on productivity and carbon(c)-sequestration potential of maize[(Zea mays L.)for green-cob in summer]-maize(for grains in rainy season)-field pea[(Pisum sativum *** winter]cropping system under humid mildtropical climate of Tripura,*** maize under NT-FB in 2012 and NT-RF in 2013 produced significantly higher green cob yield than that under ***,in rainy season,cT produced higher maize grain yield than NT *** pea seed yield was significantly the highest under *** two cropping cycles,NT systems had higher available N,P,K and 18.6e31.4%higher soil moisture content after rainy season maize than cT *** highest SOc-stock(0e30 cm)was observed under NT-FB,whereas,SOc-sequestration rate was maximum under NT-RB(0.85 Mg ha1 year1).Therefore,NT based systems can enhance the productivity and improve SOc-sequestration in cultivated soils of eastern ***,study recommended adoption of NT-RB/NT-FB to raise maize-maize-field pea system for improving productivity,improving c-sequestration and soil properties in the eastern Himalayas and similar eco-regions elsewhere.

关键词： Soil fertility carbon sequestration Soil moisture Low productivity Hill ecosystem