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A novel approach for manufacturing of layered,ultra-refractory composites using pliable,short fibre-reinforced ceramic sheets

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j.urnal of Advanced Ceramics 2023年第1期12卷 155-168页

作者： Matteo mor Antonio VINCI Simone FAILLA Pietro GALIZIA Luca ZOLI Diletta SCITI ISSMC-CNr Institute of ScienceTechnology and Sustainability for CeramicsVia Granarolo 6448018 Faenza(RA)Italy

A new additive technique for manufacturing of short fibre-reinforced ultra-refractory ceramics is *** technique allows the fabrication of solvent-free,thin(~100µm),flexible,and easy-to-handle sheets suitable for fabricating homogeneous or layered structures.A large range of compositions,in terms of matrix and fibre volumetric contents,from 0%to 100%is *** amount of short carbon fibres incorporated in the sheets ranged from 20 to 50 vol%,whereas the fibre length ranged from 3 to 5 *** matrix composition investigated with this technique consisted of ZrB_(2)/SiC/Y_(2)O_(3).By increasing the fibre amount from 35 to 50 vol%,an improvement of mechanical properties was ***-point flexural strength(σ)ranged from 107 to 140 MPa,depending on the amount of carbon fibres(Cf).The same holds true for the work of fracture,ranging from 108 to 253 j.m^(2).Functionally graded composites were fabricated by overlapping sheets with a fibre gradient(0%-50%).

关键词： ultra-high-temperature ceramics(UHTCs) ceramic matrix composites(CMCs) short carbon fibres mechanical properties

Pd-gate MOS sensor for detection of methanol and propanol

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j.urnal of Natural Gas Chemistry 2011年第2期20卷 123-127页

作者： Preeti Pandey j. K. Srivastava V. N. Mishra r. Dwivedi Center for research in Microelectronics Department of Electronics Engineering Institute of Technology Banaras Hindu University

The present paper focused on the detection of methanol and propanol using Pd-gate metal-oxide-semiconductor （MOS） sensor. Surface mor- phology and composition of the gate film were studied by scanning electron microscopy （SEM） and atomic force microscopy （AFM）. The response of the sensor for propanol and methanol was measured as shift in capacitance-voltage （C-V） and conductance-voltage （G-V） curves of the MOS structure. The sensitivity of the sensor towards methanol was found to be greater than that towards propanol. It was 58.2% for methanol and 32% for propanol （at 0.6 V, 1 MHz） in terms of capacitance measurements, while in terms of conductance results the sensitivity was found to be 57.2% for methanol and 38.9% for propanol at 1 kHz. The discontinuities or cracks present in the microstructure of the gate material are believed to be mainly responsible for the high sensitivity of the sensor, going with the decomposition of gas molecules and subsequent hydrogen permeation through Pd.

关键词： MOS structure gas sensor palladium cracks sensitivity

Prognostic value of ^(13)C-phenylalanine breath test on predicting survival in patients with chronic liver failure

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World j.urnal of Gastroenterology 2007年第34期13卷 4579-4585页

作者： I Gallardo-Wong S morán G rodríguez-Leal B Castaeda-romero r Mera j.Poo M Uribe M Dehesa Laboratory of Gastrohepatology research CMN Siglo ⅩⅩI Mexican Institute of Social Security Mexico Gastroenterology Departament CMN Siglo ⅩⅩI Mexican Institute of Social Security Mexico Department of Pathology Louisiana State University Health Sciences Center New Orleans Louisiana United States Hospital Médica Sur Mexico

AIM: To evaluate the prognostic value of percentage of 13C-phenylalanine oxidation (13C-PheOx) obtained by 13C-phenylalanine breath test (13C-PheBT) on the survival of patients with chronic liver failure. METHODS: The hepatic function was determined by standard liver blood tests and the percentage of 13C-PheOx in 118 chronic liver failure patients. The follow-up period was of 64 mo. Survival analysis was performed by the Kaplan-Meier method and variables that were significant (P riate analysis and subsequently introduced in a multivariate analysis according to the hazard model proposed by Cox. rESULTS: Forty-one patients died due to progressive liver failure during the follow-up period. The probability of survival at 12, 24, 36, 48 and 64 mo was 0.88, 0.78, 0.66, 0.57 and 0.19, respectively. Multivariate analysis demonstrated that Child-Pugh classes, age, creatinine and the percentage of 13C-PheOx (Hr 0.338, 95% CI: 0.150-0.762, P = 0.009) were independent predictors of survival. When Child-Pugh classes were replaced by all the parameters of the score, only albumin, bilirubin, creatinine, age and the percentage of 13C-PheOx (Hr 0.449, 95% CI: 0.206-0.979, P = 0.034) were found to be independent predictors of ***: Percentage of 13C-PheOx obtained by 13C-PheBT is a strong predictor of survival in patients with chronic liver disease.

关键词： ^13C-phenylalanine breath test Liver cirrhosis Chronic liver failure Survival

Germanium nanoislands grown by radio frequency magnetron sputtering: Annealing time dependent surface morphology and photoluminescence

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Chinese Physics B 2013年第9期22卷 600-604页

作者： Alireza Samavati Z.Othaman S.K.Ghoshal r.j.Amj.d Ibn Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia Advanced Optical Material research Group Department of PhysicsFaculty of ScienceUniversiti Teknologi Malaysia

Structural and optical properties of ～ 20 nm Ge nanoislands grown on Si（100） by radio frequency （rI） magnetron sputtering under varying annealing conditions are reported. rapid thermal annealing at a temperature of 600 ℃ for 30 s, 90 s, and 120 s are performed to examine the influence of annealing time on the surface morphology and photoluminescence properties. X-ray diffraction spectra reveal prominent Ge and GeO2 peaks highly sensitive to the annealing time. Atomic force microscope micrographs of the as-grown sample show pyramidal nanoislands with relatively high-density （～ 10^11 cm^-2）. The nanoislands become dome-shaped upon annealing through a coarsening process mediated by Oswald ripening. The room temperature photoluminescence peaks for both as-grown （～ 3.29 eV） and annealed （～ 3.19 eV） samples consist of high intensity and broad emission, attributed to the effect of quantum confinement. The red shift （～ 0.10 eV） of the emission peak is attributed to the change in the size of the Ge nanoislands caused by annealing. Our easy fabrication method may contribute to the development of Ge nanostructure-based optoelectronics.

关键词： germanium nanoislands radio frequency magnetron sputtering photoluminescence surface mor-phology

Craniofacial morphological microevolution of Holocene populations in northern China

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Chinese Science Bulletin 2007年第12期52卷 1661-1668页

作者： WU Xiuj.e LIU Wu ZHANG QuanChao ZHU Hong Christopher j. NOrTON Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China research Center for Chinese Frontier Archaeology Jilin University Changchun 130012 China Laboratory of Quatemary Paleontology Northern Arizona University Flagstaff AZ 86011-4099 USA

In order to better understand microevolutionary processes in Holocene Chinese craniofacial mor- phology, an analysis has been done on 21 metric traits on Neolithic (n=161), Bronze Age (n=423) and modern (n=134) adult male skulls from northern China. The results indicate that the physical characters of these Chinese populations evolved throughout the Holocene. From the Neolithic to Bronze Age to present day, general trends include: cranial and facial sizes decrease; the nose gets narrower and longer; the orbits become narrower and higher; the head is more globular. The expression of the cranial features varies between the different time periods. The decrease in cranial size primarily occurred from the Bronze Age to present day. However, the decrease in facial size, the narrowing of the nose, and the elevation of the orbits took place throughout the Holocene. These traits are likely still evolving. This evolving pattern of the cranial features for the Holocene Chinese populations is similar to that found elsewhere in the world. The decrease in overall craniofacial size is associated with changes in climate and diet. In addition, it is possible that the craniofacial morphological microevolution is controlled by human evolutionary mechanisms.

关键词：全新世中国人人类微进化颅面形态

Effect of moisture and fungal exposure on the mechanical properties of hem-fir plywood

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j.urnal of Forestry research 2005年第4期16卷 299-300页

作者： WANG Wei-hong Scott Kent Camille Freitag rorbert j. leichti j.ffrey j. morrell Key Lab. of Bio-based Material Science and Technology of Ministry of Education Northeast Forestry University Harbin 150040 P. R. China Department of Wood Science and Engineering Oregon State University USA

Hem-fir plywood were exposed to two brown rot fungi, Gloeophyllum trabeum and Postia placenta, and one white rot fungus, Trametes versicolor, to investigate the effect of fungal decay on mechanical properties of plywood. results showed that modulus of rupture （mor） and modulus of elasticity （MOE） of hem-fir plywood declined significantly by inoculating fungi, and weight loss of sample had a modest decrease. The fungi also made a greater effect on mor than on MOE. Of three fungi, Postia placenta caused a most significant weight loss, and Gloeophyllum trabeum resulted in a largest flexural properties loss. Substantial declines in mor and MOE of hem-fir plywood were also observed when the plywood samples were stored under wet conditions over 15 weeks, even in the absence of fungal attack.

关键词： Fungus decay Weight loss Flexural properties Moist condition Plywood mor, MOE

Variation in sexual dimorphism and assortative mating do not predict genetic divergence in the sexually dimorphic Goodeid fish Girardinichthys multiradiatus

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Current Zoology 2012年第3期58卷 440-452页

作者： C. MACIAS GArCIA G SMITH C. GONZALEZ ZUArTH j. A. GrAVES M. G. rITCHIE Departamento de Ecologia Evolutiva Instituto de Ecologia UNAM A. E 70-275 C. E 04510 M6xico DE M6xico School of Biology University of St Andrews St Andrews Fife KY16 9TH Scotland UK

Sexual dimorphism is often used as a proxy for the intensity of sexual selection in comparative studies of sexual selection and diversification. The Mexican Goodeinae are a group of livebearing freshwater fishes with large variation between species in sexual dimorphism in body shape. Previously we found an association between variation in morphological sexual dimorphism between species and the amount of gene flow within populations in the Goodeinae. Here we have examined if mor- phological differentiation within a single dimorphic species is related to assortative mating or gene flow between populations. In the Amarillo fish Girardinichthys multiradiatus studies have shown that exaggerated male fins are targets of female preferences. We find that populations of the species differ in the level of sexual dimorphism displayed due to faster evolution of differences in male than female morphology. However, this does not predict variation in assortative mating tests in the laboratory; in fact dif- ferences in male morphology are negatively correlated with assortative mating. Microsatellite markers reveal significant genetic differences between populations. However, gene flow is not predicted by either.morphological differences or assortative mating. rather, it demonstrates a pattern of isolation by distance with greater differentiation between watersheds. We discuss the caveats of predicting behavioural and genetic divergence from so-called proxies of sexual selection [Current Zoology 58 （3）： 440-452, 2012].

关键词： Sexual dimorphism Assortative mating Genetic distance Speciation Viviparous fish

Fe-Mn nodules associated with hydrocarbon seeps： A new discovery in the Gulf of Cadiz （eastern central Atlantic）

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Episodes 2007年第3期30卷 187-196页

作者： Fj.Gonzdlez L．Somoza r．Lunar j.Marffnez-Frias j.A．Marffnrubi T.Torres j.E．oniz V.Diaz-del-rio MarineGeologyDv GeologicalSurveyofSpain（IGME）．C／RiosRosas2328003MadridSpain．E-mail：fj-gonzalez@igme．es Departamento de Cristalografla Y Mineralogia UniversidadComplutensedeMadridUCM．C／JoseAntonio-Novais2CiudadUniversitaria28040MadridSpain． Centro de AstrobiologiaCSIC／INTA．29006Torrej.ndeArdozMadrid Spain． Laboratorio de Estratigraffa Biomolecular（ETSIM／UPM）．C／rfosrosas21 28003MadridSpain． Centro Oceanografico de Mailaga InstitutoEspafiol de OceanograffaIEO．Apdo．28529640Fuengirola（Mailaga）Spain

The Gulf of Cadiz is situated geologically at the Gibraltar Arc, the westernmost arc of the Alpine- Himalayan orogenic belt. Based on extensive previous studies that include swath bathymetry, multi-channel and very high-resolution seismic reflection, gravime- try, magnetism, heat flow probes, and underwater photography surveys, more than 500 polymetallic nodules were collected at water depths ranging from 850 to 1000 m, associated with hydrocarbon-derived carbonate chimneys, slabs, and crusts. Nodules show a wide range of sizes, densities, weights and mor- phologies. Nodules are composed of multiple milli- metre-thick layers of Fe and Mn oxyhydroxides sur- rounding a nucleus composed of Early-Middle Mio- cene plastic marls, which were expulsed from underly- ing units by fluid venting. Nodules show a high mean abundance of Fe （39.03%）, moderate Mn （5.84%）,

关键词：碳氢化合物渗出物加的斯海湾大西洋铁锰

Is There a relationship between Endotheline-1, Vascular Cell Adhesion Molecule-1 and the Arterial Hypotension Observed during Spinal Anesthesia?

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j.urnal of Biosciences and Medicines 2021年第1期9卷 64-85页

作者： j. F. Nnang Essone K. Nzé Pascal G. Edj. Nkhilli N. Ekegue Diaw mor C. P. Akagha Kondé P. Nzoghe Nguéma E. Anyunzok E. r. Obame C. Allognon B. Nguéma Asseko F. Ovono Abessolo E. Ngou Milama Department of Physiology Faculty of Medicine and Health Sciences of Libreville (USS) Libreville Gabon Department of Anesthesia and Emergency resuscitation The University Hospital of Owendo Libreville Gabon Department of Anesthesia and Emergency resuscitation The Mother Child University Hospital Center Libreville Gabon Department of Anesthesia and resuscitation The Army Instruction Hospital Libreville Gabon Laboratory of Biology and Physiological Functional Explorations UCAD Dakar Senegal Department of Medicine The University Hospital of Libreville Libreville Gabon Department of Epidemiology Biostatistics and Medical Mathematics USS Libreville Gabon Department of Surgery The University Hospital of Libreville Libreville Gabon Department of Chemistry-Biochemistry Faculty of Medicine and Health Sciences USS Libreville Gabon

Introduction: The involvement of the endothelial dysfunction (ED) in arterial hypotension (AHPT) post of spinal anesthesia (SA) has not been established. Obj.ctive: To determine if there is a relationship between ED a... 详细信息

rong>Introduction:rong> The involvement of the endothelial dysfunction (ED) in arterial hypotension (AHPT) post of spinal anesthesia (SA) has not been established. rong>Obj.ctive: rong>To determine if there is a relationship between ED and AHPT observed during the 1st 15 minutes after SA. rong>Population and Methods:rong> The study concerned 40 people who were to benefit from a programmed herniorrhaphy under SA and 40 controls (SA-). The correlations between mean plasma concentrations of endothelin-1 (CmET-1, pg/ml) and Vascular Cell Adhesion Molecule-1 (CmVCAM-1, pg/ml) taken from SA+ one hour before (H0), then 15 minutes after the SA (H15) and the mean arterial pression (AMP, mmHg) with heart rate (bpm) were analyzed (p rong>results:rong> CmET-1 and CmVCAM-1 of SA- were 1.07 and 3.34, respectively, compared to 1.12 (p = 0.735) and 3.57 (p = 0.862) in SA+ at H0 and H15. In SA+, at H15, CmET-1 was 1.13 (p = 0.823) and CmVCAM-1 was 3.57 (p = 0.257). In SA-, a negative correlation existed between CmET-1 and CmVCAM-1 (r = -0.438;p = 0.005). Conversely, in SA+, whether at H0 (r = -0.31;p = 0.051) or at H15 (r = 0.024;p = 0.883), no correlation existed between CmET-1 and CmVCAM-1, nor between MAP and ED markers (r = 0.111;p = 0.325). rong>Conclusion: rong>These results show that there is no relationship between the AHPT which occurs during the first fifteen minutes post SA, CmVCAM-1 and CmET-1. moreover, these data suggest that ED is not involved in AHPT post SA.

关键词： Endothelin-1 VCAM-1 Hypotension Endothelial Dysfunction Spinal Anesthesia