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chinese chemical Letters 2008年第7期19卷 780-782页

作者： Surinder Berar Urmila Berar satish c.gupta Ramesh c.Kamboj Department of chemistry Kurukshetra UniversityKurukshetra 136119India

Photocyclisation of substituted （E）-3-hydroxy-2-（V-methyl-2＇-phenylvinyl）-4-oxo-4H-1-benzopyrans to yield linear novel tricyclic 9H-furo[3,2-b]chromen-9-ones and angular fused tetracyclic xanthenones is described.

关键词： 9H-Furo(3,2-b)chromen-9-one Photocyclisation Xanthenones

Studies on impact sensitivity of nanosized trinitrotoluene (TNT) confined in silica processed by sol-gel method

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Defence Technology（防务技术） 2016年第1期12卷 46-51页

作者： s.v.ingale p.b.wagh p.u.sastry c.b.basak d.bandyopadhyay s.b.phapale satish c.gupta Applied Physics Division Bhabha Atomic Research Centre Mumbai India Solid State Physics Division Bhabha Atomic Research Centre Mumbai India Glass andAdvanced Materials Division Bhabha Atomic Research Centre Mumbai India Heavy Water Division Bhabha Atomic Research Centre Mumbai India chemistry Division Bhabha Atomic Research Centre Mumbai India

Nano-sized trinitrotoluene(TNT) material restrained in silica gel has been prepared by using the sol-gel process to study the effect of varying porosity in gel on the sensitivity of TNT. The TNT content in the gel has been varied from 60 to 90 wt %(at fixed acetone/tetramethoxysilane ratio of 50). Also, for a fixed TNT content of 75 wt %, the pore structure in the gel has been varied by changing the ratio of silica gel precursor to the solvent. The resultant TNT–silica gel composites have been characterized using scanning electron microscopy, thermal analysis, small angle X-ray scattering and surface area analysis techniques. Impact sensitivity studies were carried out using Fall Hammer Impact Test. The results showed that the sensitivity of nanostructured explosives prepared by sol-gel process can be tailored precisely by controlling the process parameters.

关键词：溶胶-凝胶法三硝基甲苯 TNT 敏感性二氧化硅纳米溶胶-凝胶过程扫描电子显微镜

Some Aspects of Pressure Induced ω→β Transformation in Group IV B Elements

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Some Aspects of Pressure Induced ω→β Transformation in Gr...

Spatio-temporal variability in microfossil and geochemical records of cenomanian-Turonian oceanic anoxic event-2: a review

18th International conference on High Pressure Science and Technology

作者： K.D.Joshi G.Jyoti satish c.gupta S.K.Sikka High Pressure Physics Division Bhabha Atomic Research centre Mumbai India 400085 High Pressure Physics Division Bhabha Atomic Research centre Mumbai India 400085 High Pressure Physics Division Bhabha Atomic Research centre Mumbai India 400085 High Pressure Physics Division Bhabha Atomic Research centre Mumbai India 400085

＜正＞ Recently,there has been considerable interest in thetheoretical and experimental work on the pressure inducedphase transition in group IVB elements,Ti,Zr and Hf[1-3].These elements are known to undergo α （hcp） to ω(threeatom simple hexagonal phase transition at few GPa[1].Using Linear Muffin Tin Orbital （LMTO）method,Gyanchandani *** predicted new ω to β（bcc） structuraltransition in Zr and Hf[2].This was later experimentallyconfirmed[3],however,the experimental transitionpressures did not match well with *** betterunderstanding of ω→β phase transition in these elements inthe present work,we have performed more accuratecalculations employing full-potential linearised augmentedplane wave method in conjunction with generalizedgradient density approximation for exchange *** to obtaining excellent agreement between our

关键词： Transition Pressures Theoretical d-substates

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Journal of Palaeogeography 2024年第4期13卷 646-674页

作者： c.P.Sooraj Shweta gupta Jahnavi Punekar Department of Earth Sciences Indian Institute of Technology Bombay

The cenomanian-Turonian boundary oceanic anoxic event(OAE-2; Bonarelli event; ～94 Ma) is associated with a species turnover in the marine calcareous microfossil record, widespread marine anoxia,black shale deposition and positive δ13c excursions. This study reviews 141 cTBE sites globally, aiming to understand micropaleontological, geochemical, and sedimentological expressions of OAE-2. There is a clear palaeogeographic and palaeobathymetric heterogeneity in the development of OAE-2 marine anoxia. A majority of the documented OAE-2 sites are from deep marine environments. The calcareous nannoplankton and benthic foraminifera record a diversity decline, while planktic foraminifera shows community level shifts and no major mass extinction. The variability of total organic carbon in OAE-2 sediments across sites(10 wt.%) and the δ13c profiles(diachronous) have been attributed to different mechanisms of anoxia *** increased primary “productivity model” gains support from productivity proxies(e.g., Ba, P, cu, Ni),redox-sensitive elements(e.g., Mn, Mo, U, V, As), and eutrophic genera(e.g., benthic foraminifera Gabonita spp., calcareous nannofossils Biscutum spp. and Zeugrhabdotus erectus). The enhanced organic carbon“preservation model” in stratified(semi) restricted basins gains support from sites with lower enrichment of redox-sensitive elements and oligotrophic flora and fauna in the OAE-2 records. Geochronology of the caribbean and the High Atlantic Large Igneous Province events(cLIP and HALIP) mark them as likely triggers of the OAE-2 related global perturbation of marine biogeochemistry. Volcanic triggers may have caused climate warming, altered hydrological cycles, enhanced continental weathering, shifts in ocean circulation, and nutrient flows. Addressing knowledge gaps, further research is urged, utilizing innovative proxies, and exploring underrepresented depositional systems to comprehensively understand OAE-2 onset and biotic crisis.

关键词： Oceanic anoxic Event-2 Global organic carbon distribution Geochemical proxies Marine calcifiers Palaeoceanography

Improving Heat Transfer in Parabolic Trough Solar collectors by Magnetic Nanofluids

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Energy Engineering 2024年第4期121卷 835-848页

作者： Ritesh Singh Abhishek gupta Akshoy Ranjan Paul Bireswar Paul Suvash c.Saha Department of Applied Mechanics Motilal Nehru National Institute of Technology AllahabadPrayagrajIndia Department of Mechanical and Mechatronic Engineering University of Technology SydneySydneyAustralia

A parabolic trough solar collector(PTSc)converts solar radiation into thermal ***,low thermal efficiency of PTSc poses a hindrance to the deployment of solar thermal power *** performance of PTSc is enhanced in this study by incorporating magnetic nanoparticles into the working *** circular receiver pipe,with dimensions of 66 mm diameter,2 mm thickness,and 24 m length,is exposed to uniform temperature and velocity *** working fluid,Therminol-66,is supplemented with Fe3O4 magnetic nanoparticles at concentrations ranging from 1%to 4%.The findings demonstrate that the inclusion of nanoparticles increases the convective heat transfer coefficient(HTc)of the PTSc,with higher nanoparticle volume fractions leading to greater heat transfer but increased pressure *** thermal enhancement factor(TEF)of the PTSc is positively affected by the volume fraction of nanoparticles,both with and without a magnetic ***,the scenario with a 4%nanoparticle volume fraction and a magnetic field strength of 250 G exhibits the highest TEF,indicating superior thermal *** findings offer potential avenues for improving the efficiency of PTScs in solar thermal plants by introducing magnetic nanoparticles into the working fluid.

关键词： Parabolic trough solar collector(PTSc) magnetic nanofluid(MNF) heat transfer convective heat transfer coefficient(HTc) thermal enhancement factor(TEF)

Boron neutron capture therapy of cancer:where do we stand now?

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cancer communications 2024年第8期44卷 889-892页

作者： Rolf F.Barth Gong Wu Maria da Graca H.Vicente John c Grecula Nilendu gupta Department of Pathology The Ohio State UniversityColumbusOhioUSA Mass Spectrometry and Proteomics Facility The Ohio State UniversityColumbusOhioUSA Department of chemistry Louisiana State UniversityBaton RougeLouisianaUSA Department of Radiation Oncology The Ohio State UniversityColumbusOhioUSA

1 INTRODUcTION,This is the third Editorial/commentary that one of us(***)has written relating to boron neutron capture therapy(BNcT)[1,2].For those readers who are unfamiliar with BNcT we would refer them to several recent comprehensive reviews[3–5].The second Editorial ended on a hopeful note that with the introduction of acceleratorbased neutron sources(ABNSs),BNcT would enter into the mainstream of radiation therapy[2].

关键词： boron 1,2 neutron

Energy-growth nexus for‘Renewable Energy country Attractiveness Index’countries:Evidence from new econometric methods

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Geoscience Frontiers 2024年第3期15卷 298-311页

作者： Mandeep Mahendru Aviral Kumar Tiwari Gagan Deep Sharma Solomon Nathaniel Mansi gupta Szechenyi Istvan University GyorHungary Indian Institute of Management BodhgayaIndia University School of Management Studies Guru Gobind Singh Indraprastha UniversitySector 16 CDwarkaNew DelhiIndia Department of Economics University of LagosAkokaNigeria centre for Financial Innovation S P Jain Institute of Management and ResearchMumbaiIndia

This study explores the connections between renewable energy consumption(REc),non-renewable energy consumption(NREc),gross fixed capital formation(GFcF),the labor force(LF),and economic growth(GDP)in Renewable Energy country Attractiveness Index(REcAI)countries for *** quantify the nexus between REc,NREc,and GDP while utilizing a production model framework and including the measures of labor and capital,for suggesting a phase-wise strategy to attain the sustainable development *** use robust methodologies including Lagrange Multiplier(LM)panel unit root tests with trend shifts,Westerlund cointegration test,LM bootstrap technique for cointegration with breaks,continuously updated fully modified(cUP-FM)and continuously updated bias-corrected(cUPBc)estimators,Augmented Mean Group(AMG)approach,fully modified ordinary least squares,dynamic ordinary least squares,canonical cointegrating Regression(ccR),and panel causality test proposed by canning&*** compute non-parametric time-varying coefficients with fixed effects for seeing the impact of GFcF,LF,REc,and NREc on *** results press upon policymakers to shift toward clean energy and REc for attaining the environmental goals(SDGs 6,7,13,and 15)and the economic goals(SDGs 1,2,8,and 10).While this shift would help developed economies,which have already attained the economic goals,to progress on the front of environmental goals,it would enable developing countries to progress on both fronts in a balanced manner.

关键词： Renewable energy consumption Economic growth Non-renewable energy consumption cUP-Bc cUP-FM Time-varying coefficients with fixed effects

The diagnostic conundrum in necrotizing otitis externa

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 59-65页

作者： Abiya A.Ahmed Shaan Rashid Vinay K.gupta Neil c.Molony Keshav K.gupta Bradford Royal Infirmary Bradford Teaching Hospitals NHS Foundation TrustWest BromwichWest YorkshireUK Sandwell and West Birmingham Hospitals NHS Trust West BromwichUK Russells Hall Hospital DudleyUK

Necrotizing otitis externa(NOE)is an aggressive and fast‐evolving infection of the external auditory *** diagnoses and untreated cases can lead to severe,even fatal consequences and so early diagnosis and treatment are *** is a notoriously challenging diagnosis to *** is therefore important to understand what diagnostic modalities are available and how otolaryngologists can use them to accurately treat such an aggressive *** review aims to evaluate the different diagnostic options available in NOE and discuss their advantages and limitations,thus,providing an up‐to‐date picture of the multimodal approach required in the diagnosis of this disease.

关键词： diagnostic malignant otitis externa necrotizing osteomyelitis skull base osteomyelitis temporal bone osteomyelitis

Effect of solar wind plasma parameters on space weather

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Research in Astronomy and Astrophysics 2015年第1期15卷 85-106页

作者： Balveer S.Rathore Dinesh c.gupta Subhash c.Kaushik School of Study in Physics Jiwaji UniversityGwalior Madhya Pradesh India

Today’s challenge for space weather research is to quantitatively predict the dynamics of the magnetosphere from measured solar wind and interplanetary magnetic field（IMF） conditions. correlative studies between geomagnetic storms（GMSs）and the various interplanetary（IP） field/plasma parameters have been performed to search for the causes of geomagnetic activity and develop models for predicting the occurrence of GMSs, which are important for space weather predictions. We find a possible relation between GMSs and solar wind and IMF parameters in three different situations and also derived the linear relation for all parameters in three *** the basis of the present statistical study, we develop an empirical model. With the help of this model, we can predict all categories of GMSs. This model is based on the following fact： the total IMF Btotalcan be used to trigger an alarm for GMSs, when sudden changes in total magnetic field Btotaloccur. This is the first alarm condition for a storm’s arrival. It is observed in the present study that the southward Bzcomponent of the IMF is an important factor for describing GMSs. A result of the paper is that the magnitude of Bzis maximum neither during the initial phase（at the instant of the IP shock） nor during the main phase（at the instant of Disturbance storm time（Dst） minimum）. It is seen in this study that there is a time delay between the maximum value of southward Bzand the Dst minimum, and this time delay can be used in the prediction of the intensity of a magnetic storm two-three hours before the main phase of a GMS. A linear relation has been derived between the maximum value of the southward component of Bzand the Dst, which is Dst =（-0.06）＋（7.65）Bz＋ *** auxiliary conditions should be fulfilled with this, for example the speed of the solar wind should, on average, be 350 km s-1 to 750 km s-1, plasma β should be low and, most importantly, plasma temperature should be low for intense storms. If the plasma tem

关键词： solar wind geomagnetic storms(GMSs) interplanetary magnetic field(IMF)

Methyl-salicylate:A surveillance system fortriggering immunity in neighboring plants

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Journal of Integrative Plant Biology 2024年第2期66卷 163-165页

作者： Saumya Jaiswal Durgesh Kumar Tripathi Ravi gupta JingHe Zhong-Hua chen Vijay Pratap Singh Plant Physiology Laboratory Department of Botany C.M.P.Degree CollegeA Constituent Post Graduate College ofUniversity of AllahabadPrayagraj 211002India crop Nanobiology and Molecular Stress Physiology LabAmity Institute of Organic Agriculture Amity University UttarPradeshNoida 201313India college of General Education Kookmin UniversitySeoul 02707South Korea School of Science Western Sydney UniversitySydney 2751New South WalesAustralia Hawkesbury Institute for the Environment Western SydneyUniversitySydney 2751New South WalesAustralia

Plant behavioral actions have been one of the major topicsof research in plant biology and *** actionsfrom plants are determined by their instant structural andphysical reactions to the circumstances(Bouwmeester et al.,2019).Upon sensing abiotic factors such as salinity,flooding,high temperature,drought,plants make suitable changes intheir physiology and behavior to survive such harsh conditions.

关键词： immunity neighboring salinity