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Impact of composition ratio on the structure and optical properties of(1-x)MnFe_(2)O_4/(x)ZnMn_(2)O_4 nanocomposite

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Chinese Physics B 2022年第7期31卷 481-489页

作者： Zein k.Heiba Mohamed Bakr Mohamed Ali A.Alkathiri Sameh I.Ahmed A A Alhazime Department of Physics Faculty of ScienceAin shams UniversityCairo 11566Egypt Physics Department Faculty of ScienceTaibah UniversityAl-Madina al MunawarahSaudi Arabia Depatment of Physics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

(1-x)MnFe_(2)O_(4)(MFO)/xZnMn_(2)O_(4)(ZMO)(x=0,0.2,0.5,0.8,and 1.0)nanocomposite samples were prepared using co-precipitation *** phase percentage,cell parameters,and crystallite size of MFO and ZMO phases in each nanocomposite sample were calculated using Rietveld refinement *** x-ray diffraction(XRD)analysis and Fourier-transform infrared spectroscopy techniques established the variation in the lattice parameters of each phase are due to permutation of all cations among the octahedral and tetrahedral sites of MFO and *** different oxidation states of different ions in all samples were determined using x-ray photoelectron spectroscopy(XPS)*** variation in absorbance of the nanocomposite samples with composition parameter(x)is dependent on the wavelength *** optical bandgap of the nanocomposite samples is decreased as the content of ZMO phase *** effect of alloying on the refractive index,extinction coefficient,dielectric constant,optical conductivity,and the nonlinear optical behaviors of all samples were studied in *** nanocomposite sample x=0.5 disclosed upgraded optical parameters with the highest refractive index,optical conductivity,and PL intensity,which nominate it to be functional in various application fields.

关键词： MFO and ZMO composite XPS structure optical

Rice Husk Templated Mesoporous ZnO Nanostructures for Ethanol Sensing at Room Temperature

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Chinese Physics Letters 2015年第7期32卷 202-205页

作者： M. Chitra k. Uthayarani N. Raj asekaran N. Neelakandeswari E. k. Girija D. Pathinettam Padiyan Department of Physics Sri Ramakrishna Engineering College Coimbatore 641022 India Department of Chemistry Sri Ramakrishna Engineering College Coimbatore 641022 India Department of Physics Periyar University Salem 636011 India Department of Physics Manonmaniam Sundaranar University Abhishekapatti Tirunelveli 627012 lndia

Mesoporous zinc oxide nanostructures are successfully synthesized via the sol-gel route by using a rice husk.a. the template for ethanol sensing at room temperature. The structure and morphology of the nanostructures are characterized by x-ray diffraction, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and nitrogen adsorption-desorption analyses. The mechanism for the growth of zinc oxide nanostructures over the biotemplate is proposed. SEM and TEM observations also reveal the formation of spherical zinc oxide nanoparticles over the interwoven fibrous network. Multiple sized pores having pore diameter ranging from 10- 4Ohm is also evidenced from the pore size distribution plot. The larger surface area and porous nature of the material lead to high sensitivity （40.93% for 300 ppm of ethanol）, quick response （42s） and recovery （40 s） towards ethanol at 30014. The porous nature of the interwoven fibre-like network.a.fords mass transportation of ethanol vapor, which results in faster surface accessibility, and hence it acts as a potential candidate for ethanol sensing at room temperature.

关键词： ZnO Rice Husk Templated Mesoporous ZnO Nanostructures for Ethanol Sensing at Room Temperature

When fats commit crimes: fatty acid metabolism, cancer stemness and therapeutic resistance

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Cancer Communications 2018年第1期38卷 499-510页

作者： Ching-Ying kuo David k.a.n Department of Clinical Laboratory Sciences and Medical Biotechnology College of MedicineNational Taiwan UniversityTaipei 10048TaiwanChina Department of Diabetes Complications and Metabolism Diabetes and Metabolism Research InstituteBeckman Research InstituteCity of HopeDuarteCA 91010USA Irell and Manella Graduate School of Biological Sciences City of HopeDuarteCA 91010USA

The role of fatty acid metabolism,including both anabolic and catabolic reactions in cancer has gained increas-ing attention in recent *** studies have shown that aberrant expression of the genes involved in fatty acid synthesis or fatty acid oxidation correlate with malignant phenotypes including metastasis,therapeutic resistance and *** phenotypes are also strongly associated with the presence of a small percentage of unique cells among the total tumor cell *** distinct group of cells may have the ability to self-renew and propagate or may be able to develop resistance to cancer therapies independent of genetic ***,these cells are referred to as cancer stem cells/tumor-initiating cells/drug-tolerant persisters,which are often refractory to cancer treatment and difficult to ***,interconversion between cancer cells and cancer stem cells/tumor-initiating cells/drug-tolerant persisters may occur and makes treatment even more *** review highlights recent findings on the relationship between fatty acid metabolism,cancer stemness and therapeutic resistance and prompts discussion about the potential mechanisms by which fatty acid metabolism regulates the fate of cancer cells and therapeutic resistance.

关键词： Fatty acid synthesis Fatty acid oxidation Fatty acid metabolism Lipogenic phenotype Cancer stem cells Tumor-initiating cells Cancer cell plasticity Therapeutic resistance Drug-tolerant persisters

Influence of deposition rate on the structural, optical and electrical properties of electron beam evaporated SnO_2 thin films for transparent conducting electrode applications

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Journal of Semiconductors 2018年第8期39卷 20-26页

作者： Nitin kumar Bhawana Joshi k.a.okan Department of Applied Physics Gautam Buddha University Materials Science Division Inter University Accelerator Centre

The role of deposition rate in the structural, optical and electrical properties of SnOthin films deposited by electron beam evaporation method is investigated by varying the deposition powers viz. 50, 75, and 100 *** structural characterization of the films is done by X-ray diffraction(XRD) technique. The surface morphology of the films is studied by scanning electron microscopy(SEM). Rutherford back scattering(RBS) measurements revealed the thickness of the films ranging from 200 nm to 400 and also a change in the concentration of oxygen vacancies which is found to be the maximum in the film deposited at the lowest deposition rate. Optical absorption spectrum is recorded using the UV–V is spectroscopy and the films are found to be transparent in nature. A shift in the absorption edge is observed and is attributed to a different level of allowed energy states in conduction band minimum. The Hall effect and electrical measurements show a variation in the carrier concentrations, mobility and resistivity of the films. In order to explore a better compromise in electrical and optical properties for transparent electrode applications, skin depths calculations are also done to find the optimized values of carrier concentration and mobility.

关键词： SnO_2 oxygen vacancies carrier concentration deposition rate electron beam evaporation

Fault classification and reconfiguration of distribution ystems using equivalent capacity margin method

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Frontiers in Energy 2012年第4期6卷 394-402页

作者： k.Sathish kUMAR T.JAYABARATHI School of Electrical Engineering VIT UniversityVellore 632014India

This paper investigates the capability of support vector machines （SVM） for prediction of fault classification and the use of the concept of equivalent capacity margin （ECM） for restoration of the power system. The SVM, as a novel type of machine learning based on statistical learning theory, achieves good generalization ability by adopting a structural risk minimization （SRM） induction principle aimed at minimizing a bound on the generalization error of a model rather than the minimization of the error on the training data only. Here, the SVM has been used as a classification. The inputs of the SVM model are power and voltage values. An equation has been developed for the prediction of the fault in the power system based on the developed SVM model. The next steps of this paper are the restoration and reconfiguration by using the ECM concept, the development of a code, and the testing of the results with various load outages, which have been executed for a 12 load system.

关键词： support vector machines (SVM) structuralrisk minimization (SRM) equivalent capacity margin(ECM) restoration fault classification

350 μm map of the Ophiuchus molecular cloud: core mass function

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Science China(Physics,Mechanics & Astronomy) 2015年第2期58卷 114-124页

作者： ZHANG GuoYin LI Di HYDE Ashley k QIAN Lei LYU HuaLei WU ZhongZu College of Science/Department of Physics Guizhou University key Laboratory of Radio Astronomy Chinese Academy of Sciences National Astronomical Observatories Chinese Academy of Sciences Space Science Institute Department of Astronomy California Institute of Technology Astrophysics Group Imperial College London

Stars are born in dense cores of molecular clouds. The core mass function(CMF), which is the mass distribution of dense cores, is important for understanding the stellar initial mass function(IMF). We obtained 350 μm dust continuum data using the SHARC-II camera at the Caltech Submillimeter Observatory(CSO) telescope. A 350 μm map covering 0.25 deg2 of the Ophiuchus molecular cloud was created by mosaicing 56 separate scans. The CSO telescope had an angular resolution of 9′′, corresponding to 1.2×103AU at the distance of the Ophiuchus molecular cloud(131 pc). The data was reduced using the Comprehensive Reduction Utility for SHARC-II(CRUSH). The flux density map was analyzed using the Gauss Clumps algorithm, within which 75 cores has been identified. We used the Spitzer c2 d catalogs to separate the cores into 63 starless cores and 12 protostellar cores. By locating Jeans instabilities, 55 prestellar cores(a subcategory of starless cores) were also identified. The excitation temperatures, which were derived from FCRAO12 CO data, help to improve the accuracy of the masses of the cores. We adopted a Monte Carlo approach to analyze the CMF with two types of functional forms; power law and log-normal. The whole and prestellar CMF are both well fitted by a log-normal distribution, with μ =-1.18±0.10, σ = 0.58±0.05 and μ = 1.40±0.10, σ = 0.50±0.05 respectively. This finding suggests that turbulence influences the evolution of the Ophiuchus molecular cloud.

关键词：分子云蛇夫座群发功能初始质量函数对数正态分布加州理工学院蒙特卡罗方法 CMF

Settlement predictions of footings on sands using probabilisticanalysis

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Journal of Rock Mechanics and Geotechnical Engineering 2016年第2期8卷 198-203页

作者： felipe carvalho bungenstab kátia vanessa bicalho federal university of espirito santo VitóriaBrazil

The design of footings on sands is often controlled by settlement rather than bearing ***,settlement predictions are essential in the design of shallow ***,predicted settlements of footings are highly dependent on the chosen elastic modulus and the used *** paper presents the use of probabilistic analysis to evaluate the variability of predicted settlements of footings on sands,focusing on the load curve(predicted settlements)*** methodologies,the first-and second-order second-moment(FOSM and SOSM),and Monte Carlo simulation(MCS),for calculating the mean and variance of the estimated settlements through Schmertmann(1970)’s equation,are presented and *** soil beneath the footing is treated as an uncorrelated layered material,so the total settlement and variance are found by adding up the increments of the *** deformability modulus(ESi)is considered as the only independent random *** an example of application,a hypothetical case of a typical subsoil in the state of Espirito Santo,southeast of Brazil,is *** results indicate that there is a significant similarity between the SOSM and MCS methods,while the FOSM method underestimates the results due to the non-consideration of the high-order terms in Taylor’s *** contribution of the knowledge of the uncertainties in settlement prediction can provide a safer design.

关键词： Footings Settlements Probabilities Deformability modulus

Genotoxic Effects of PAH Containing Sludge Extracts in Chinese Hamster Ovary Cell Cultures

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Biomedical and Environmental Sciences 2003年第1期16卷 68-82页

作者： k.kRISHNAMURTHI FONTDEVI T.CHAk.a.ARTI Environmental Biotechnology Division National Environmental Engineering Research InstituteNehru MargNagpur-440020IndiaEnvironmental Biotechnology DivisionNational Environmental Engineering Research InstituteNehru MargNagpur-440020IndiaEnvironmental Biotechnology DivisionNational Environmental Engineering Research InstituteNehru MargNagpur-440020India

Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now questioned by a growing segment of society. Methods keeping the above fact in mind, we have conducted in the present study the genotoxicity evaluation of oily sludge samples generated from a petroleum refinery and petrochemical industry and ETP sludge from petroleum refinery using DNA damage, chromosomal aberration, p53 protein induction and apoptosis in short term in vitro mammalian Chinese Hamster Ovary cell cultures. Results It is evident from the results that the oily sludge compounds derived from petroleum refinery and petrochemical industry could cause DNA damage, chromosomal aberration, p53 protein accumulation and apoptotic cell death on exposure to oily sludge extracts in the presence of metabolic activation system (S-9 mix), however, ETP sludge extract could not cause significant genotoxicity in comparison to oily sludge extract and negative control. Conclusion The effect may be attributed to polycyclic aromatic hydrocarbons present in the samples as evidenced from GC-MS.

关键词： DNA damage Chromosomal aberration p53 protein induction Apoptosis Genotoxicity Polycyclic aromatic hydrocarbons (PAHs) Gas chromatograph mass spectrometer (GC-MS)

Diurnal and spatial variations of soil NO_x fluxes in the northern steppe of China

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Journal of Environmental Sciences 2015年第6期27卷 54-61页

作者： Bing Wang Xinqing Lee Benny k.G. Theng Jianzhong Cheng Fang Yang State key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Landcare Research Private Bag 11052 Graduate University of the Chinese Academy of Sciences

NOx emissions from biogenic sources in soils play a significant role in the gaseous loss of soil nitrogen and consequent changes in tropospheric chemistry. In order to investigate the characteristics of NOx fluxes and factors influencing these fluxes in degraded sandy grasslands in northern China, diurnal and spatial variations of NOx fluxes were measured in situ. A dynamic flux chamber method was used at eight sites with various vegetation coverages and soil types in the northern steppe of China in the summer season of *** of NOx from soils with plant covers were generally higher than those in the corresponding bare vegetation-free soils, indicating that the canopy plays an important role in the exchange of NOx between soil and air. The fluxes of NOx increased in the daytime,and decreased during the nighttime, with peak emissions occurring between 12：00 and14：00. The results of multiple linear regression analysis indicated that the diurnal variation of NOx fluxes was positively correlated with soil temperature（P 〈 0.05） and negatively with soil moisture content（P 〈 0.05）. Based on measurement over a season, the overall variation in NOx flux was lower than that of soil nitrogen contents, suggesting that the gaseous loss of N from the grasslands of northern China was not a significant contributor to the high C/N in the northern steppe of China. The concentration of NOx emitted from soils in the region did not exceed the 1-hr National Ambient Air Quality Standard（0.25 mg/m^3）.

关键词： Desertification N cycle Land-use change Nitrogen oxides