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Analysis of isoquinoline alkaloids from Mahonia leschenaultia and Mahonia napaulensis roots using UHPLC-Orbitrap-MSn and UHPLC-QqQ LIT-MS/MS

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Journal of Pharmaceutical Analysis 2017年第2期7卷 77-86页

作者： Awantika singh Vikas Bajpai Sunil kumar ajay kumar singh Rawat Brijesh kumar Sophisticated Analytical Instrument Facility Division CSIR-Central Drug Research InstituteLucknow 226031India Academy of Scientific and Innovative Research New Delhi 110001India Pharmacognosy and Ethnopharmacology Division CSIR-National Botanical Research InstituteLucknow 226001India

Mahonia leschenaultia（ML） and Mahonia napaulensis（MN） are less known and unexplored medicinal plants of the family Berberidaceae. They are used by the Todas of Nilgiris in their religious and medical practices but chemically less identified. Hence, we decided to do extensive phytochemical analysis to explore the potential of these plant extracts. An ultrahigh performance electrospray tandem mass spectrometry（UHPLC-ESI-MS/MS）method was successfully developed for qualitative analysis of the bioactive components in Mahonia species using Orbitrap Velos Pro mass spectrometer. Sixteen compounds were identified by comparison of their retention times and mass spectra（MS） with authentic standards and reported literature. Multi-stage mass spectra（MS（2-8）） for the identification of protoberberine and aporphine alkaloids showed the sequential expulsion of all the substituents attached with their basic skeleton followed by CO loss. Eight of the identified compounds（berberine, jatrorrhizine, palmatine, magnoflorine, isocorydine, glaucine, tetrahydropalmatine and tetrahydroberberine） were simultaneously determined by another UHPLC-ESI-MS/MS method under the multiple reactions monitoring（MRM） mode quantitatively using triple quadrupole linear ion trap mass spectrometer. The analytical method was validated for 8 bioactive compounds with overall recovery in the range98.5%-103.6%（RSD≤2.2%）, precise（RSD≤2.07%） and linear（r≥0.9995） over the concentration range of 0.5-1000 ng/mL and successfully applied in ML and MN roots, which suggests the suitability of the proposed approach for the routine analysis of Mahonia species and their quality control.

关键词： Orbitrap-MS QqQLIT-MS Mahonia leschenaultia Mahonia napaulensis Isoquinoline alkaloids

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Process Tolerant and Power Efficient SRAM Cell for Internet of Things Applications

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Computers, Materials & Continua 2022年第8期72卷 3425-3446页

作者： T.G.Sargunam Lim Way Soong C.M.R.Prabhu ajay kumar singh Faculty of Engineering and Technology Multimedia UniversityMelaka75450Malaysia School of Engineering and Computing Manipal International UniversityNilai71800Malaysia Electronics and Communication Engineering Department NIIT UniversityNeemarana301705India

The use of Internet of Things(IoT)applications become dominant in many *** on-chip data processing and computations are also increasing *** battery enabled and low leakage memory system at subthreshold regime is a critical requirement for these IoT *** cache memory designed on Static Random-Access Memory(SRAM)cell with features such as low power,high speed,and process tolerance are highly important for the IoT memory ***,a process tolerant SRAM cell with low power,improved delay and better stability is presented in this research *** proposed cell comprises 11 transistors designed with symmetric approach for write operations and single ended circuit for read operations that exhibits an average dynamic power saving of 43.55%and 47.75%for write and 35.59%and 36.56%for read operations compared to 6 T and 8 T SRAM *** cell shows an improved write delay of 26.46%and 37.16%over 6 T and 8T and read delay is lowered by 50.64%and 72.90%against 6 T and 10 T *** symmetric design used in core latch to improve the write noise margin(WNM)by 17.78%and 6.67%whereas the single ended separate read circuit improves the Read Static Noise Margin(RSNM)by 1.88x and 0.33x compared to 6 T and 8T *** read power delay product and write power delay product are lower by 1.94x,1.39x and 0.17x,2.02x than 6 T and 8 T cells *** lower variability from 5000 samples validates the robustness of the proposed *** simulations are carried out in Cadence virtuoso simulator tool with Generic Process Design Kit(GPDK)45 nm technology file in this work.

关键词： SRAM cell low power process efficient read stability write ability static noise margin PVT variation internet of things

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Hopf bifurcation in a delayed prey-predator model with prey refuge involving fear effect

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International Journal of Biomathematics 2024年第5期17卷 1-32页

作者： Ankit Parwaliya Anuraj singh ajay kumar Department of Applied Sciences ABV-Indian Institute of Information Technology and ManagementGwalior 474015India

This work investigates a prey-predator model featuring a Holling-type II functional response,in which the fear effect of predation on the prey species,as well as prey refuge,are ***,the model assumes that the growth rate of the prey population decreases as a result of the fear of ***,the detection of the predator by the prey species is subject to a delay known as the fear response delay,which is incorporated into the *** paper establishes the preliminary conditions for the solution of the delayed model,including positivity,boundedness and *** paper discusses the existence and stability of equilibrium points in the *** particular,the paper considers the discrete delay as a bifurcation parameter,demonstrating that the system undergoes Hopf bifurcation at a critical value of the delay *** direction and stability of periodic solutions are determined using central manifold and normal form ***,the global stability of the model is established at axial and positive equilibrium *** extensive numerical simulation is presented to validate the analytical findings,including the continuation of the equilibrium branch for positive equilibrium points.

关键词： Hopf bifurcation fear effect prey refuge periodic solutions time delay branch off

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Determination of flavonoids,polyphenols and antioxidant activity of Tephrosia purpurea:a seasonal study

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Journal of Integrative Medicine 2016年第6期14卷 447-455页

作者： Madan Mohan Pandey Sayyada Khatoon Subha Rastogi ajay kumar singh Rawat Pharmacognosy&Ethnopharmacology Division CSIR-National Botanical Research InstituteLucknow 226 001India

OBJECTIVE： Tephrosia purpurea （Linn.） Pers. is widely used in traditional medicine to treat liver disorders, febrile attacks, enlargement and obstruction of liver, spleen, and kidney. In the present study investigations were carried out to determine the seasonal impact on the content of flavonoid glycosides and on antioxidant activities so as to identify the optimal time of harvesting. METHODS： The plant materials were collected in different seasons during 2013-2014. Air-dried, powdered plant materials were extracted with 95% ethanol and ethanol：water （1：1 ） by ultrasound-assisted extraction process. Their chemical composition in terms of total polyphenol and flavonoid contents （TPCs and TFCs） was determined using modified colorimetric Folin-Ciocalteu method and aluminum chloride colorimetric assay respectively. To determine the in vitro antioxidant activity, diphenyl-picryl hydrazyl （DPPH） radical-scavenging assay and total antioxidant capacity by phosphomolybdate antioxidant assay were carried out. High-performance liquid chromatography （HPLC）/photo-diode array （PDA） analysis was used to quantify the flavonoid glycosides in the samples collected in different seasons. Correlation studies were also carried out between antioxidant activities and TPCs. RESULTS： The highest TPC and TFC were found to be in the 95% ethanolic extract of the August sample and the lowest in the 50% hydro-alcoholic extract of the plant sample collected in winter season. It was observed that in both the assays used to determine the antioxidant activity, the 95% ethanolic extracts in all the seasons showed a higher activity than their respective 50% hydro- alcoholic extracts with an increase in activity as we go from cold to hot to rainy seasons. Based on correlation analysis, DPPH radical-scavenging activities as well as the spectrophotometrically measured phosphomolybdenum complex were also strongly correlated with TPC of the extracts, The most abundant flavonoid glycoside was quercetin-3-O-

关键词： Tephrosia chromatography, high-performance liquid flavonoid glycosides seasonal variation antioxidant effect

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Effect of using borax decahydrate as nanoparticles additive in blends of spirulina biodiesel/diesel on combustion characteristics and knock intensity

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Clean Energy 2024年第3期8卷 62-78页

作者： ajay Partap singh Puneet singh Gautam Mechanical Engineering Department IIMT University Meerut250001 Uttar PradeshIndia

In this extensive investigation,the impact of borax decahydrate as a fuel additive in a diesel single-cylinder engine was rigorously *** decahydrate was introduced at concentrations of 5,15,25 and 35 g in 500 ml of biodiesel,forming five unique fuel mixtures with conventional diesel:90%diesel+10%spirulina biodiesel(SB10),SB10+1 g borax decahydrate(SB10B1),SB10+3 g borax decahydrate(SB10B3),SB10+5 g borax decahydrate(SB10B5)and SB10+7 g borax decahydrate(SB10B7).The investigation encompassed four diverse loading conditions and yielded insightful ***,at full load,SB10B3 exhibited a higher cylinder peak pressure than diesel,reaching 69.25 *** release rate profiles demonstrated superior efficiency for SB10 at 50%load,with a cumulative heat release rate of 950 J/°CA,which is lower than the 1050 J/°CA of *** intensity(KI)evaluations revealed that,although SB10 and SB10B1 exhibited higher KI than diesel at full load due to elevated peak pressure,SB10B7 showed no knocking across all loads,indicative of reduced in-cylinder *** meticulous numerical analysis emphasizes the potential of borax decahydrate as a catalyst and enhancer,providing valuable insights into the combustion dynamics of these alternative fuel blends and their viability for sustainable and efficient engine *** summary,out of all the blends,SB10B3 could be a potential diesel fuel replacement fuel for compression-ignition engines.

关键词： spirulina biodiesel borax decahydrate diesel engine combustion knock intensity HRR in-cylinder pressure

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Geochemistry and mineral chemistry of the armoor granitoids,eastern dharwar craton: implications for the redox conditions and tectono-magmatic environment

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Acta Geochimica 2024年第1期43卷 110-133页

作者： A.ajay kumar Ch.Ashok Department of Geology Osmania UniversityHyderabad 500007India CSIR-National Geophysical Research Institute UppalHyderabad 500007India

The mineralogical and geochemical characteristics of the K-rich granites from the Armoor granitic rocks in the northeastern portion of the Eastern Dharwar Craton(EDC) are *** order to understand its physicochemical conditions,the petrogenesis of the granitoid was explained from biotite chemistry and geochemical *** of mineral chemistry expose that compositionally,K-feldspar and plagioclase in Armoor granite rocks range from An0,Ab_(3-5.9),Or_(94-96.9) and An_(5-29,-Ab71.9-94.9),Or_(0-1.5),*** mineral chemistry of biotite crystals exhibits composition that varies from primary to re-equilibrated primary *** biotites from the Armoor granites generally exhibit an I-type trend,with calc-alkaline parental magma in a subduction *** chemistry of granites displays magnetite(oxidized)series nature,which has oxygen fugacity(fO_(2))=-15.1 to-16.7(log_(10) bar),under high oxidizing *** and pressure estimates for the crystallization of Armoor granites based on biotite composition are T=612-716 ℃ and 1.0-0.4 kbar,***,these rocks are metaluminous to slightly peraluminous and magnesian,with calc-alkaline potassiumrich *** the chondrite normalized REE diagram,the granites have positive europium anomalies;rich Sr/Y,(Dy/Yb)_(N) ratios and reduced Mg#,Rb/Sr,Rb,Sr indicate that the melting of earlier rocks,crystal accumulation and residual garnet source formed at high *** examined granites show that they are produced from the melting of crustal ***,the extensive analyses of the described Armoor granite suggest that they were produced by crust sources and developed under oxidizing conditions in subduction setting.

关键词： Armoor granites Oxygen fugacity Crystal accumulation Remelting Subduction

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Dosimetric Comparison of Fixed and Flexible Geometry ICRT Applicators in Patients Treated for Carcinoma Cervix

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2015年第1期4卷 1-6页

作者： Sukhvir singh Arti Sarin Manoj kumar Semwal ajay kumar singh Pankaj Goyal Ashok kumar Department of Radiation Oncology Army Hospital (R&R) Delhi Cantonment New Delhi India

In intracavitary radiotherapy (ICRT) for cancer cervix, applicator geometry has the potential to impact the doses to organs at risk (OARs) and the coverage of the target volume. At our centre two Varian made Fletcher-style applicator sets, namely defined (fixed) geometry and flexible geometry, are used for ICRT. In the present work, the two types of applicators were compared dosimetrically as per the recommendations of the International Commission on Radiation Units and Measurements (ICRU-38) while delivering high dose rate brachytherapy. Twenty four patients who underwent ICRT were considered for this study. Radiographic method was used for treatment planning on Abacus planning system. ICRU-38 recommended parameters were estimated and compared. Flexible geometry applicator showed 8.8% and 16% higher bladder and rectum point doses as compared to the fixed geometry one but the difference was statistically not significant. The thickness of the pear-shaped isodose volume was larger for the flexible geometry implant also indicating towards higher doses to OARs. The higher bladder and rectum point doses in the case of flexible applicator will need to be validated by a larger data set.

关键词： Carcinoma Cervix Intracavitary Radiotherapy Applicator Geometry Dosimetry

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Application of Response Surface Methodology for Analysing and Optimizing the Finned Solar Air Heater

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Journal of Thermal Science 2024年第3期33卷 985-1009页

作者： Vineet singh Vinod singh YADAV Vaibhav TRIVEDI Manoj kumar Niraj kumar Department of Mechanical Engineering School of Engineering&TechnologyIFTM UniversityMoradabadUttar PradeshIndia Department of Mechanical Engineering NITUttarakhandPauriUttarakhandIndia Department of Electronics and Communication Engineering Jaypee Institute of Information TechnologyNoidaUttar Pradesh201309India

In this research paper,a solar air heater with triangular fins has been experimentally analysed and ***,an experimental set-up of a solar air heater having triangular fins has been developed at the location of 28.10°N,78.23°*** heat transfer rate through fins and fins efficiency has been determined by the Finite Difference Method model *** experimental data and modeled data of response parameters have been optimized in MINITAB-17 software by the Response Surface Methodology *** creating the response surface design,three input parameters have been selected namely solar intensity,Reynolds number,and fin base-to-height *** range of solar intensity,Reynolds number,and fin base-to-height ratio is 600 to 1000W/m^(2),4000 to 6000,and 0.4 to 0.8 *** response surface design has been analyzed by calculating the outlet temperature,friction factor,Nusselt number,fin efficiency,thermal performance factor,and exergy *** optimum settings of input parameters:solar intensity is 1000 W/m^(2);Reynolds number is 4969.7,and the fin base to height ratio is 0.6060,on which these response:namely outlet temperature of 92.531℃,friction factor of 0.2350,Nusselt number of 127.761,thermal efficiency of 50.836%,thermal performance factor of 1.4947,and exergy efficiency of 8.762%.

关键词： solar air heater optimization fins exergy response surface methodology air

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Effect of cooling media on bead geometry,microstructure,and mechanical properties of wire arc additive manufactured IN718 alloy

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Advances in Manufacturing 2024年第1期12卷 124-149页

作者： Parveen kumar Satish kumar Sharma Ratnesh kumar Raj singh Department of Mechanical Engineering Thapar Institute of Engineering and TechnologyPatialaPunjab147004India

This work aims to present and explore thermal management techniques for the wire arc additive manufacturing(WAAM)of IN718 *** heat can be mitigated via air or water *** this study,the material was deposited under four different heat-input conditions with air or water *** air cooling,the layer is deposited in a normal atmospheric air environment,whereas with water cooling,the material is deposited inside a water tank by varying the water *** validate the air and water cooling thermal management techniques,IN718 single-pass and multilayer linear walls were deposited using the bidirectional gas metal arc welding based WAAM setup under four different heat input *** the deposition of single layers,the temperature profiles were recorded,and the geometric and microstructural features were *** multilayer wall structures,the mechanical properties(hardness,tensile strength,and elongation)were determined and assessed using the corresponding microstructural features explored through scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and electron backscatter diffraction(EBSD)*** microstructure observed through SEM analysis in the building direction was found to be nonhomogenous compared with that in the deposition ***,water cooling was found to govern bead characteristics,such as wall width and *** grain size and anisotropy of the mechanical properties also decreased in the water-cooled ***,water cooling is an economical and efficient method to mitigate excessive heat accumulation in WAAM-deposited IN718.

关键词： Air cooling Water cooling IN718 Bead characteristics Microstructure Electron backscatter diffraction(EBSD)

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Thermodynamic properties and phase diagram of quark matter within non-extensive Polyakov chiral SU(3)quark mean field model

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Chinese Physics C 2024年第5期48卷 60-71页

作者： Dhananjay singh Arvind kumar Department of Physics Dr.B R Ambedkar National Institute of Technology JalandharJalandhar–144008PunjabIndia

In the present study,we applied Tsallis non-extensive statistics to investigate the thermodynamic properties and phase diagram of quark matter in the Polyakov chiral SU(3)quark mean field *** this model,the properties of the quark matter were modified through the scalar fieldsσ,ζ,δ,χ,vector fieldsω,ρ,ϕ,and Polyakov fieldsΦandΦ¯at finite temperature and chemical ***-extensive effects were introduced through a dimensionless parameter q,and the results were compared to those of the extensive case(q→1).In the non-extensive case,the exponential in the Fermi-Dirac(FD)function was modified to a q-exponential *** influence of the q parameter on the thermodynamic properties,pressure,energy,and entropy density,as well as trace anomaly,was *** speed of sound and specific heat with non-extensive effects were also ***,the effect of non-extensivity on the deconfinement phase transition as well as the chiral phase transition of u,d,and s quarks was *** found that the critical end point(CEP),which defines the point in the(T−μ)phase diagram where the order of the phase transition changes,shifts to a lower value of temperature,TCEP,and a higher value of chemical potential,μCEP,as the non-extensivity is increased,that is,q>1.

关键词： quark matter quark mean field model QCD phase diagram non-extensive statistics

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