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Electrochemical process of titanium extraction

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中国有色金属学会会刊：英文版 2007年第2期17卷 429-433页

作者： ch. RVS. nAGESh c. S. RAMAch.nDRAn Defence Metallurgical Research Laboratory HyderabadA.P. India-500058

A wide variety of processes are being pursued by researchers for cost effective extraction of titanium metal. Electrochemical processes are promising due to simplicity and being less capital intensive. Some of the promising electrochemical processes of titanium extraction were reviewed and the results of laboratory scale experiments on electrochemical reduction of TiO2 granules were brought out. Some of the kinetic parameters of the reduction process were discussed while presenting the quality improvements achieved in the experimentation.

关键词：钛萃取电化学还原过程动力学参数

Spectroscopic and fluorescence properties of Sm^(3+)-doped zincfluorophosphate glasses

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Journal of Rare Earths 2014年第10期32卷 918-926页

作者： V.B.Sreedhar ch.Basavapoornima c.K.Jayasankar Department of Physics Sri Venkateswara University Department of Physics National Degree and P.G. College

Optical absorption and fluorescence spectra of Sm3＋-doped zincfluorophosphate glasses with molar composition of 44P2O5＋17K20＋9Al2O3＋（30-χ）Znf2＋χSm2O3 （χ=0.01 mol.%, 0.05 mol.%, 0.1 mol.%, 0.5 mol.%, 1.0 mol.%, 2.0 and 3.0 mol.%） referred as PKAZfSm were prepared by melt quench.ng technique and were characterized through Raman, absorption, emission and decay curve analysis. from the absorption spectra, Judd-Ofelt intensity parameters were determined and were used to predict radiative properties such as transition probabilities （AR, radiative lifetimes （τR）, branch.ng ratios （βR）, effective bandwidths （△λeff） and stimulated emission cross-section （σ（λp）） for the excited 4G5/2 luminescent level. The decay curve for the 4G5/2 level was single exponential for lower concentration and became non-exponential for higher concentrations. The non-exponential nature of the decay curves of the 4G5/2 level increased with increase in Sm3＋ ions concentration accompanied by decrease in lifetime due to energy transfer processes among the Sm3＋ ions. The non-exponential decay curves was well fitted to the generalized Inokuti-hirayama model for S=6, indicating that the energy transfer among optically active ions was of dipole-dipole interaction. The cross-relaxation mech.nism responsible for the quench.ng of lifetimes and the effect of variation of concentration on the spectroscopic properties were also discussed.

关键词： zincfluorophosphate glasses samarium Raman spectrum optical properties fluorescence properties rare earths

Studies on Thermal conductivity of Diamond film

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high Technology Letters 1995年第1期1卷 91-94页

作者： Jingbiao, c. hong, ch. Jifa, Zh. Dayan, B. Rongchuan, f. Univ of Science and Technology of China Hefei China

Diamond films were prepared by electron-assisted chemical vapor deposition (EAcVD) system, and the thermal diffusivities of the films with or without substrate were studied by use of photothermal deflection (PTD) technique. The results show that less non-diamond component and larger crystalline size result in higher thermal conductivity of cVD diamond film. The influence of substrate on the measurement of thermal conductivity of the film was investigated, and a simple two-layer heat conduction model is given to account for the influence and used to draw the thermal conductivity of the film from the effective thermal diffusivity of film/substrate system.

关键词： Diamond film Photothermal deflection Thermal conductivity Substrate

Low serum levels of ghrelin are associated with gallstone disease

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World Journal of Gastroenterology 2006年第19期12卷 3096-3100页

作者： nahum Méndez-Sánchez Guadalupe Ponciano-Rodríguez Luisa Bermejo-Martínez Antonio R Villa norberto c chávez-Tapia Daniel Zamora-Valdés Raúl Pichardo-Bahena Blanca Barredo-Prieto Martha h Uribe-Ramos Martha h Ramos héctor A Baptista-González Misael Uribe Liver Unit Biomedical Research Department Medica Sur Clinic and FoundationMexico CityMexico faculty of Medicine national Autonomous University of Mexico (UnAM) Mexico CityMexico clinical Research Department national Institute of Perinatology Mexico CityMexico clinical Epidemiology Unit national Institute of Medical Sciences and nutrition Mexico CityMexico

AIM： To explore the role of ghrelin in gallstone disease. METhODS： We carried out a cross-sectional study in 150 subjects, 38 with gallstones （cases） and 112 controls. We also did a real-time PcR-RT study in twenty gallbladder samples each. Body mass index （BnI）, serum insulin, ghrelin, and serum lipids were measured. Logistic regression analyses （univariate and multivariate） were conducted to estimate the probability of gallstone disease associated with serum ghrelin concentrations. RESULTS： cases were statistically different from controls in gender distribution （P = 0.01）, age （53 vs 44 yr, P = 0.002）, BnI （28 vs 25; P = 0.004）, and glucose （5.26 vs 4.98 mmol/L; P = 0.05）. The prevalence of ghrelin serum levels above the third tercile was lower in subjects without metabolic syndrome （P 〈 0.05）. In a multivariate model, we found a protective effect, when ghrelin values were higher than the median value （OR = 0.27, 95%cI 0.09-0.82, P = 0.02）. Twenty （20%） gallbladder specimens expressed ghrelin mRnA. cOncLUSIOn： Serum ghrelin concentrations are associated with a protective effect of GD.

关键词： Gallstones Obesity Ghrelin Gallbladder Gastrointestinal hormones

Determination of Particle Sizes and crystalline Phases on colloidal Silicon nanoparticle Suspensions

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Journal of Materials Science & Technology 1999年第6期15卷 548-550页

作者： S.M. Scholz and h h.fmann(Powder Technology Laboratory, Department of Materials Science, Swiss federal Institiute of Technology Lausanne,ch-1015 Lausanne, Switzerland) Powder Technology Laboratory Department of Materials Science Swiss Federal Institiute of Technology Lausanne CH-1015 Lausanne Switzerland

Particle size and crystallinity of silicon nanoparticles were determined by analyzing the optical extinction spectra of colloidal suspensions. Experimental results from these colloids were anaiyzed using Mie theory in connection with effective medium theory, in order to determine particle sizes and their internal structure with the simple technique of optical transmission spectroscopy. By modeling an effective refractive index for the particles, the crystalline volume fraction can be extracted from extinction spectra in addition to information about the size. The crystalline volume fraction determined in this way were used to calibrate the ratio of the Raman cross sections for nanocrystalline and amorphous silicon, which was found to be σc./σa = 0.66

关键词： Determination of Particle Sizes and crystalline Phases on colloidal Silicon nanoparticle Suspensions

The Apollon 10 PW laser: experimental and theoretical investigation of the temporal characteristics

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high Power Laser Science and Engineering 2016年第3期4卷 127-133页

作者： D.n.Papadopoulos J.P.Zou c.Le Blanc G.chriaux P.Georges f.Druon G.Mennerat P.Ramirez L.Martin A.frneaux A.Beluze n.Lebas P.Monot f.Mathieu P.Audebert Laboratoire pour l'Utilisation des Lasers Intenses CNRSEcole Polytechnique Laboratoire charles fabry UMR 8501 Institut d'OptiqueCNRS Univ Paris Sud cEA Iramis SPAM

The objective of the Apollon 10 PW project is the generation of 10 PW peak power pulses of 15 fs at 1 shot min^(-1). In this paper a brief update on the current status of the Apollon project is presented, followed by a more detailed presentation of our experimental and theoretical investigations of the temporal characteristics of the laser. More specifically the design considerations as well as the technological and physical limitations to achieve the intended pulse duration and contrast are discussed.

关键词： high intensity lasers spatiotemporal effects ultrafast lasers

Adiponectin as a protective factor in hepatic steatosis

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World Journal of Gastroenterology 2005年第12期11卷 1737-1741页

作者： nahum Méndez-Sánchez norberto c.chávez-Tapia Antonio R.Villa Karla Sánchez-Lara Daniel Zamora-Valdés Martha h.Ramos Misael Uribe Liver Research Unit clinical Epidemiology Unit

AIM: Obesity and insulin resistance (IR) are closely related to hepatic steatosis (hS), and adiponectin is a hepatic insulin sensitizer that has important effects in liver function. This study aims at investigating the relationship between serum adiponectin concentration and the presence of hS. METhODS: We carried out a cross-sectional study in a check-up unit of a University hospital in Mexico city. We enrolled 196 subjects, comprising 98 subjects with hS (27 women, 71 men) and 98 controls (37 women and 61 men). Anthropometric, metabolic and biochemical variables were measured in the two groups. Serum adiponectin and leptin concentrations were determined, their association with grade of hS tested, and concentrations, according to quartiles, compared between cases and controls. X2 analysis for linear trends was used to test for a dose-response relationship and logistic regression analysis was conducted to test for a protective effect of adiponectin. RESULTS: The hS subjects were older and more obese than controls, with a central obesity pattern. In the fourth quartile of adiponectin concentrations, hS was less common and severe. In a multivariate model of the fourth quartile of the adiponectin concentrations, we observed a protective effect (OR = 0.17, 95%cI: 0.04-0.67, P= 0.01). In subjects with more severe hS, we observed higher leptin concentrations, and caloric intakes, total fat and iron consumption were higher than in controls. cOncLUSIOn: The results of the present study suggest that a high serum concentration of adiponectin is associated with a protective effect against hS.

关键词： Adiponectin hepatic steatosis Leptin Diet

carboxylesterase 1 family knockout alters drug disposition and lipid metabolism

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Acta Pharmaceutica Sinica B 2023年第2期13卷 618-631页

作者： ch.ngpei Gan Jing Wang Alejandra Martínez-chávez Michel hillebrand niels de Vries Joke Beukers Els Wagenaar Yaogeng Wang Maria c.Lebre hilde Rosing Sjoerd Klarenbeek Rahmen Bin Ali colin Pritchard Ivo huijbers Jos h.Beijnen Alfred h.Sch.nkel Division of Pharmacology the Netherlands Cancer InstituteAmsterdam 1066 CXthe Netherlands Department of Pharmacy&Pharmacology the Netherlands Cancer InstituteAmsterdam 1066 CXthe Netherlands Division of Pharmacoepidemiology and clinical Pharmacology Utrecht Institute for Pharmaceutical SciencesUtrecht UniversityUtrecht 3584 CSthe Netherlands Experimental Animal Pathology facility the Netherlands Cancer InstituteAmsterdam 1066 CXthe Netherlands Mouse clinic for cancer and Aging(MccA)Transgenic facility the Netherlands Cancer InstituteAmsterdam 1066 CXthe Netherlands

The mammalian carboxylesterase 1(ces1/cES1)family comprises several enzymes that hydrolyze many xenobiotic chemicals and endogenous *** investigate the pharmacological and physiological roles of ces1/cES1,we generated ces1 cluster knockout(ces1^(-/-))mice,and a hepatic human cES1 transgenic model in the ces1^(-/-)background(TgcES1).ces1^(-/-)mice displayed profoundly decreased conversion of the anticancer prodrug irinotecan to Sn-38 in plasma and ***1 mice exhibited enhanced metabolism of irinotecan to Sn-38 in liver and ***1 and hcES1 activity increased irinotecan toxicity,likely by enhancing the formation of pharmacodynamically active ***1^(-/-)mice also showed markedly increased capecitabine plasma exposure,which was moderately decreased in TgcES1 ***1^(-/-)mice were overweight with increased adipose tissue,white adipose tissue inflammation(in males),a higher lipid load in brown adipose tissue,and impaired blood glucose tolerance(in males).These phenotypes were mostly reversed in TgcES1 ***1 mice displayed increased triglyceride secretion from liver to plasma,together with higher triglyceride levels in the male *** results indicate that the carboxylesterase 1 family plays essential roles in drug and lipid metabolism and ***1^(-/-)and TgcES1 mice will provide excellent tools for further study of the in vivo functions of ces1/cES1 enzymes.

关键词： ces1/cES1 enzymes Irinotecan capecitabine Adipose tissue Lipid homeostasis Inflammation Triglyceride mobilization Mouse models

Synthesis and characterization of Y and Dy co-doped ceria solid electrolytes for IT-SOfcs:a microwave sintering

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Rare Metals 2021年第11期40卷 3329-3336页

作者： ch.Madhusudan Venkataramana Kasarapu Madhuri chittimadula Y.Suresh Reddy c.Vishnuvardhan Reddy Department of Physics Osmania UniversityHyderabadTelangana 500007India

In this communication,the electrical conductivities and thermal expansion studies of microwave sintered co-doped ceria ce_(0.8)Y_(0.2-x)Dy_(x)O_(2-δ)(x=0,0.05,0.10,0.15 and 0.20) solid electrolyte materials for intermediate temperature solid oxide fuel cells(IT-SOfcs)synthesized by sol-gel auto-combustion method were *** sintering at 1300℃ for 30 min was used for making dense powder *** relative densities of all the samples are noticed above 95%.Raman spectrum was characterized by the presence of a very strong band near 460 cm^(-1),which along with X-ray diffraction(XRD) analysis ascertain the sample formation with a single-phase cubic fluorite *** lattice parameter values were calculated from XRD *** images show nearly uniform grains with distinct grain *** thermal expansion coefficients(TEcs) are found to vary linearly with temperature and were measured in the range from 14.15 to 13.20×10^(-6)℃^(-1).The investigation on total ionic conductivity(TIc) was executed with variation in dopant concentration and relative oxygen *** impedance analysis reveals that the sample ce_(0.80)Y_(0.10)Dy_(0.10)O_(2-δ) displays the highest TIc,i.e.,7.5×10^(-3) S·cm^(-1) at 500℃ and minimum activation energy 0.90 eV compared to *** the highest TIc and minimum activation energy,the ce_(0.80)Y_(0.10)Dy_(0.10)O_(2-δ)might be the possible material as the solid electrolyte in intermediate temperature SOfcs.

关键词： Microwave sintering Ionic conductivity co-doped ceria Solid electrolyte Intermediate temperature solid oxide fuel cells