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npj Computational Materials 2019年第1期5卷 932-939页

作者： Nikolay Borodinov sabine Neumayer sergei v.Kalinin Olga s.Ovchinnikova rama K.vasudevan stephen Jesse Center for Nanophase Materials science Oak Ridge National LaboratoryOak RidgeTN 37831USA

The rapid development of spectral-imaging methods in scanning probe,electron,and optical microscopy in the last decade have given rise for large multidimensional *** many cases,the reduction of hyperspectral data to the lower-dimension materialsspecific parameters is based on functional fitting,where an approximate form of the fitting function is known,but the parameters of the function need to be ***,functional fits of noisy data realized via iterative methods,such as least-square gradient descent,often yield spurious results and are very sensitive to initial ***,we demonstrate an approach for the reduction of the hyperspectral data using a deep neural network approach.A combined deep neural network/least-square approach is shown to improve the effective signal-to-noise ratio of band-excitation piezoresponse force microscopy by more than an order of magnitude,allowing characterization when very small driving signals are used or when a material’s response is weak.

关键词： neural networks property

Electron Paramagnetic Resonance and Optical Absorption studies on Copper Ions in Mixed Alkali Cadmium Phosphate Glasses

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Journal of Materials science & Technology 2009年第4期25卷 531-534页

作者： G. Giridhar M. Rangacharyulu R.v.s.s.N. Ravikumar P. sambas.v. rao Department of Physics Acharya Nagarjuna University Department of Chemistry Pondicherry University

Electron paramagnetic resonance （EPR） and optical absorption studies were carried out at room temperature on copper doped mixed alkali cadmium phosphate （LiNaCdP） glasses to understand the nature and symmetry of dopant. Three samples with varying concentrations of alkali ions have been prepared. The spin Harniltonian parameters obtained from room temperature EPR spectra are： gli=2.437, 9⊥=2.096, A‖=117×10-4 cm-1, A⊥=26×10-4 cm-1 for LiNaCdP1, g‖=2.441, g⊥=2.088, A‖=121×10-4 cm-1, A⊥=25×10-4 cm-1 for LiNaCdP2and g‖=2.433,g⊥=2.096, A‖=125×10 4cm-1, A⊥=32×10-4cm-1 for LiNaCdP3. TheseEPR results indicate that the dopant Cu2＋ ion enters the glass matrix into a tetragonally elongated octahedral site. The bonding parameters evaluated by correlating optical and EPR data suggest that bonding between the central metal ion and ligands is partially covalent. The mixed alkali effect in cadmium phosphate glasses was reported.

关键词： Glasses Electron paramagnetic resonance (EPR) Optical properties

Gaussian process analysis of electron energy loss spectroscopy data:multivariate reconstruction and kernel control

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npj Computational Materials 2021年第1期7卷 1395-1404页

作者： sergei v.Kalinin Andrew R.Lupini rama K.vasudevan Maxim Ziatdinov Center for Nanophase Materials sciences Oak Ridge National LaboratoryOak RidgeTNUSA

Advances in hyperspectral imaging including electron energy loss spectroscopy bring forth the challenges of exploratory and physics-based analysis of multidimensional data *** multivariate linear unmixing methods generally explore similarities in the energy dimension,but ignore correlations in the spatial *** the same time,Gaussian process(GP)explicitly incorporate spatial correlations in the form of kernel functions but is computationally ***,we implement a GP method operating on the full spatial domain and reduced representations in the energy *** this multivariate GP,the information between the components is shared via a common spatial kernel structure,while allowing for variability in the relative noise magnitude or image *** explore the role of kernel constraints on the quality of the reconstruction,and suggest an approach for estimating them from the experimental *** further show that spatial information contained in higher-order components can be reconstructed and spatially localized.

关键词： domain kernel multivariate

structural Tuning of Low Band Gap Intermolecular Push/Pull side-chain Polymers for Organic Photovoltaic Applications

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Chinese Journal of Polymer science 2017年第9期35卷 1073-1085页

作者： Ansuman Nayak P.s. rama sreekanth santosh Kumar sahu Duryodhan sahu Department of Chemistry National Institute of Science and Technology Palur Hills Berhampur Odisha India 761008 Department of Chemistry Gandhi Institute of Engineering and Technology Gunpur Odisha India Department of Mechanical Engineering National Institute of Science and Technology Palur Hills Berhampur Odisha India 761008

A series of novel low band gap donor-acceptor （D-A） type organic co-polymers （BT-F-TPA, BT-CZ-TPA and BT-sI-TPA） consisting of electron-deficient acceptor blocks both in main chains （M1） and at the pendant （M2） were polymerized with different electron rich donor （M3-M5） blocks, i.e., 9,9-dihexyl-9H-fluorene, N-alkyl-2,7-carbazole, and 2,6-dithinosilole, respectively, via suzuki method. These polymers exhibited relatively low band gaps （1.65-1.88 ev） and broad absorption ranges （680-740 nm）. Bulk heterojunction （BHJ） solar cells incorporating these polymers as electron donors, blended with [6,6]-phenyl-C61-butyric acid methyl ester （PC61BM） or [6,6]-phenyl-Cvl-butyric acid methyl ester （PC71BM） as electron-acceptors in different weight ratios were fabricated and tested under 100 mW/cm2 of AM 1.5 with white-light illumination. The photovoltaic device containing donor BT-sI-TPA and acceptor PC71BM in 1：2 weight ratio showed the best power conversion efficiency （PCE） value of 1.88%, with open circuit voltage （voc） = 0.75 v, short circuit current density （Jsc） = 7.60 mA/cm2, and fill factor （FF） = 33.0%.

关键词： Polymer solar cells Low band gap Conducting polymers Charge transfer Donor-acceptor Bulk heterojunctionsolar cell

Petrology,genesis and geodynamic implication of the Mesoproterozoic-Late Cretaceous Timmasamudram kimberlite cluster,Wajrakarur field,Eastern Dharwar Craton,southern India

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Geoscience Frontiers 2017年第3期8卷 541-553页

作者： Ashish Dongre N.v.Chalapathi rao K.s.v.ljoen B.Lehmann Department of Geology University of Johannesburg Department of Geology Centre of Advanced StudyBanaras Hindu University Mineral Resources Technical University of Clausthal

New mineralogical and bulk-rock geochemical data for the recently recognised Mesoproterozoic （ca. 1100 Ma） and late Cretaceous （ca. 90 Ma） kimberlites in the Timmasamudram cluster （TKC） of the Wajrakarur kimberlite field （WKF）, Eastern Dbarwar Craton, southern India, are presented. On the basis of groundmass mineral chemistry （phlogopite, spinel, perovskite and clinopyroxene）, bulk-rock chem- istry （siO2, K20, low TiO2, Ba/Nb and La/sm）, and perovskite Nd isotopic compositions, the TI（-1 （mac- rocrystic variety） and TI（-4 （Macrocrystic variety） kimberlites in this cluster are here classified as orangeites （i.e. Group II kimberlites）, with geochemical characteristics that are very similar to orangeites previously described from the Bastar Craton in central India, as well as the Kaapvaal Craton in south Africa. The remaining kimberlites （e.g., TK-2, TK-3 and the TK-1 microcrystic variant）, are more similar to other 1100 Ma, Group l-type kimberlites of the Eastern Dharwar Craton, as well as the typical Group I kimberlites of the Kaapvaal Craton. Through the application of geochemical modelling, based on pub- lished carbonated peridotite/melt trace element partition coefficients, we show that the generation of the TI（C kimberlites and the orangeites results from low degrees of partial melting of a metasomatised, carbonated peridotite. Depleted mantle （TDM） Nd perovskite model ages of the 1100 Ma Timmasamudram kimberlites show that the metasomatic enrichment of their source regions are broadly similar to that of the Meso- proterozoic kimberlites of the EDC. The younger, late Cretaceous （ca. 90 Ma） TI（-1 （macrocrystic variant） and TK-4 kimberlites, as well as the orangeites from the 8astar Craton, share similar Nd model ages of 1100 Ma, consistent with a similarity in the timing of source enrichment during the amalgamation of Rodinia supercontinent. The presence of late Cretaceous diamondiferous orangeite activity, presumably related to the location of the Marion hotspot

关键词： Kimberlite Orangeite Diamond Timmasamudram Wajrakarur India

Floral extract of Tecoma stans:A potent inhibitor of gentamicin-induced nephrotoxicity in vivo

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Asian Pacific Journal of Tropical Medicine 2011年第9期4卷 680-685页

作者： Raju s Kavimani s Uma Maheshwara rao v sreeramulu Reddy K vasanth Kumar G vijaya College of Pharmacy MunaganoorRanga Reddy DistAndhra PradeshIndia-505511 Mather Theresa Post Graduate Institute of Health sciences.Gorimedu PuducherryIndia Nulla Narsimha Reddy College of Pharmacy KorremulaRanga Reddy DistAndhra Pradesh.India Assistant manager - Clinical R&D Shantha Biotechnics LimitedHyderabadAndhra Pradesh.India -500004 Health Management and Research Institute HyderabadAndhra PradeshIndia

Objective:To highlight the nephroprotective activity of ethyl acetate extract of dried flowers of Tecomu stans for its protective effects on genlamicin-induced nephrotoxicity in albino rats. Methods:For studying acute toxicity study,single oral dose of 5（KM） mg ethyl acetate floral extract/kg hodv weight was administered to albino rats（five females,five males）.Nephrotoxicity was induced in albino rats by intraperitoneal administration of gentamicin 80 mg/kg/day for eight *** of concurrent administration of ethyl acetate floral extract of Tecoma stans at a dose of 100.200 and 300 mg/kg/day given by oral mute was determined using serum creatinine,serum uric acid,blood urea nitrogen and serum urea as indicators of kidney *** study groups contained six rats in each *** nephrotoxicity of gentamicin is known to involve induction of oxidative stress,in vitro antioxidant aclivity and free radical-scavenging activity of this extract was also ***:For acute toxicity testing both female and male rats administered with the extract at a dose of 5 000 mg/*** results showed no toxicity in terms of general behavior change,mortality,or change in gross appearance of internal organs(LDsub>50sub>>5 000 mg/kg). It was observed that the ethyl acetate floral extract of Tecoma stans significantly protected rat kidneys from gentamicin-induced histopathological ***-induced glomerular congestion,peritubular and blood vessel congestion,epithelial desquamation,accumulation ol inflamnialoiy cells and necrosis of the kidney cells were found to be reduced in the groups receiving the ethyl acetate floral extract of Tecoma starts along with gentamicin in a dose dependent *** floral extract also reduced the gentamicin-induced increase in serum creatinine,serum uric acid,blood urea nitrogen and serum urea levels（P>0.01）.Conclusions: The present study indicates a verv important role of reactive oxygen species（BOs） and the relation to re

关键词： Gentamicin Tecoma stans Rats Nephrotoxicity serum urea Creatinine

Emulsion‑based evolution of Escherichia coli for higher growth yield on D‑xylose identifies central role of cyclic AMP

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systems Microbiology and Biomanufacturing 2023年第4期3卷 730-738页

作者： James s.Orr Edwin Zen Xiaoyi Wang Christopher v.rao DOE Center for Advanced Bioenergy and Bioproducts Innovation UrbanaILUSA Department of Chemical and Biomolecular Engineering University of Illinois at Urbana-Champaign600 S.Mathews Ave.UrbanaIL 61801USA Core Facility Center The First Affiliated Hospital of Nanjing Medical UniversityNanjingChina

D-xylose is an abundant sugar found in plant biomass and can be used as a renewable feedstock for the microbial production of diverse biofuels and ***,D-xylose metabolism is slow in many industrial microorganisms,at least as compared to glucose *** surprisingly,a number of approaches have been developed for improving D-xylose metabolism in diverse *** this work,we applied a previously developed evolution strategy based on media-in-oil emulsions for improving the growth yield of Escherichia coli NCM3722 on *** 30 rounds of evolutions,we isolated multiple mutants with increased growth yield on *** addition,we also observed similar increases in the growth *** mutants were selected for whole-genome *** mutants had an amber stop mutation in adenylate cyclase,which truncates nearly 60%of the ***,the ability of this mutant to grow on xylose indicated that truncated enzyme,lacking the C-terminal regulatory domain,is still *** other mutant had a point mutation in the cyclic AMP receptor protein(CRP),near the high affinity binding site for cyclic *** mutations,when intro-duced into wild type ***,were able to increase the growth yields at levels similar to the isolated *** addition to D-xylose,these mutant strains and their genetic mimics also exhibited higher growth rates and yields on glucose,lactose,and *** results suggest that the improved growth rates and yields are due to changes in the production and sensing of intracellular cyclic AMP concentrations and also suggest native concentrations are suboptimal with respect to the growth rate and yield under the growth conditions ***,these results may prove useful for engineering strains of *** for high-density fermentations or protein production.

关键词： Escherichia coli Xylose cAMP Adaptive laboratory evolution

The Role of vanadia for the selective Oxidation of Benzyl Alcohol over Heteropolymolybdate supported on Alumina

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催化学报 2011年第11期32卷 1719-1726页

作者： Pasupulet s.v. Nageswara rao Kasanneni Tirumala venkateswara rao Potharaju s. sAI PRAsAD Nakka LINGAIAH Catalysis Laboratory Inorganic and Physical Chemistty Division Indian Institute of Chemical Technology Hyderabad 500 607 lndia

A series of 12-molybdophosphoric acid (MPA) supported on v2O5 dispersed γ-Al2O3 catalysts with different vanadia loadings were prepared by impregnation and characterized by N2 adsorption-desorption, X-ray diffraction, temperature-programmed reduction, in situ laser raman spectroscopy, Uv-vis diffused reflectance spectroscopy, scanning electron microscopy, and temperature-programmed desorption of NH3 techniques. Their catalytic activities were evaluated for the vapor phase aerobic oxidation of benzyl alcohol. The catalysts exhibited high catalytic activity and the conversion of benzyl alcohol depended on the vanadia content while the catalyst with 15 wt% v2O5 content showed optimum activity. The characterization results suggest the presence of well-dispersed v2O5 and partially disintegrated Keggin ions of MPA on the support. In situ raman studies showed a reduced Mo(Iv) species when the catalysts were calcined at high temperatures. The high oxidation activity of the catalysts is related to the synergistic effect between MPA and v2O5.

关键词： molybdophosphoric acid vanadia alumina oxidation benzyl alcohol

Development and validation of stability Indicating LC Method for 10-Hydroxycamptothecin

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American Journal of Analytical Chemistry 2012年第7期3卷 470-477页

作者： Arala venkateshwarlu A. v. rama rao Khagga Mukkanti Analytical Development Laboratory Avra Laboratories Private Limited Hyderabad India Institute of science & Technology Jawaharlal Nehru Technological University Hyderabad India

The present method gives a detailed description for the development and validation of a simple stability indicating reverse phase liquid chromatographic method for 10-hydroxycamptothecin(10-HCTN) in the presence of its impurities namely Imp A and Imp B along with degradation products generated from forced degradation studies. The drug was subjected to stress conditions of hydrolysis (acid, base and neutral), oxidative, photolytic and thermal stress degradation. Degradation was observed when subjected to treatment with peroxides or under conditions normally used for typical acid and base hydrolysis. The drug was found to be stable under other stress conditions attempted such as photolytic and thermal. successful separation and isolation of the drug from related impurities and degradation products formed under stress conditions was achieved on an Inertsil ODs-3v (250 mm × 4.6 mm, 5 μm) column using a phosphate buffer, acetonitrile, methanol and Nanopure water. The developed HPLC method was.v.lidated with respect to specificity, linearity, accuracy, precision, sensitivity, robustness and solution stability. The assay method was found to be linear in the range of 0.16 mg/mL to 0.24 mg/mL with a correlation coefficient of 0.999 and the linearity of the impurities was established from 0.02% (LOQ) to 0.3%. Recoveries of assay and impurities were found between 99.4% and 100.3%. The developed HPLC method can be used to determine the related substances and assay determinations of 10-HCTN and also to evaluate the quality and long term stability of production samples.

关键词： 10-Hydroxycamptothecin HPLC Method validation Degradation Anti-Cancer Activity and Related substances

Geochemical assessment of a siliceous limestone sample for cement making

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Chinese Journal Of Geochemistry 2011年第1期30卷 33-39页

作者： rao D.s. vijayakumar T.v. Prabhakar s. Bhaskar Raju G. National Metallurgical Laboratory-Madras Centre CsIR Madras Complex Taramani Chennai-600 113 India

A low grade siliceous limestone sample from the Jayantipuram mine of Andhra Pradesh, India, has been investigated for its suitability for cement making. Petrological as well as X-ray diffraction pattern studies indicated that the limestone sample was crystalline and dominantly composed of calcite and quartz. They are simple in mineralogy, and yet they have variable silica and lime contents. Geochemical analysis results of twenty five hand picked samples indicated that the limestone from the Jayantipuram mine shows a wide range of variations in LOI (29.94% to 40.64%), siO2 (6.14% to 27.18%), CaO (37.93% to 50.78%), Al2O3 (0.49% to 2.27%) and Fe2O3 (0.28% to 2.4%). MgO, K2O, Na2O, TiO2 and MnO2 are present in traces. CaO with LOI shows a strong positive correlation where as CaO with siO2 shows a strong negative correlation because of mineralogical factors. The chemical composition of the limestone reflects its mineralogical composition. The distribution of various elements in the acid-soluble fraction has been studied by the factor analysis method in order to interpret in terms of their mineralogy, sedimentary environment and diagenesis. Mineralogy, recrystallization and other diagenetic changes are the main factors affecting the distribution of the elements and their mutual relationships in the limestone. The aim of this paper is also to analyze how significantly the two parameters, silica modulus and lime saturation factor, influence this low grade siliceous limestone sample from the Jayantipuram mine of Andhra Pradesh, India, for the cement making process from the geochemical data.

关键词：灰岩样品水泥生产地球化学硅质石灰石矿评估因子分析方法化学数据处理