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Journal of Magnesium and Alloys 2017年第1期5卷 64-73页

作者： h.Medhashree A.Nityananda Shetty department of chemistry national institute of technology karnatakasurathkalsrinivasnagarmangalorekarnataka 575025india

The effects of sulfate ion concentration,temperature and medium ph on the corrosion of Mg–Al–Zn–Mn alloy in 30%aqueous ethylene glycol solution have been investigated by electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy *** morphology of the alloy was examined before and after immersing in the corrosive media by scanning electron microscopy(SEM)and energy dispersion X-ray(EDX)*** energy,enthalpy of activation and entropy of activation were calculated from Arrhenius equation and transition state theory *** obtained results indicate that,the rate of corrosion increases with the increase in sulfate ion concentration and temperature of the medium and decreases with the increase in the ph of the medium.

关键词： Mg-Al-Zn alloy EIS SEM EDX

What Causes the Springtime Tropospheric Ozone Maximum over Northeast Asia?

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Advances in Atmospheric Sciences 2010年第3期27卷 543-551页

作者： Jae h.KIM hyunjin LEE Department of Atmospheric Science Pusan National University

Scientists have long debated the relative importance of tropospheric photochemical production versus stratospheric influx as causes of the springtime tropospheric ozone maximum over northern mid-latitudes. This paper investigates whether or not stratospheric intrusion and photochemistry play a significant role in the springtime ozone maximum over Northeast Asia, where ozone measurements are sparse. We examine how tropospheric ozone seasonalities over Naha （26°N, 128°E）, Kagoshima （31°N, 131°E）, and Pohang （36°N, 129°E）, which are located on the same meridional line, are related to the timing and location of the jet stream. The ozone seasonality shows a gradual increase from January to the maximum ozone month, which corresponds to April at Naha, May at Kagoshima, and June at Pohang. In order to examine the occurrence of stratospheric intrusion, we analyze a correlation between jet stream activity and tropospheric ozone seasonality. From these analyses, we did not find any favorable evidence supporting the hypothesis that the springtime enhancement may result from stratospheric intrusion. According to trajectory analysis for vertical and horizontal origins of the airmass, a gradual increasing tendency in ozone amounts from January until the onset of monsoon was similar to the increasing ozone formation tendency from winter to spring over China's Mainland, which has been observed during the build-up of tropospheric ozone over Central Europe in the winter-spring transition period due to photochemistry. Overall, the analyses suggest that photochemistry is the most important contributor to observed ozone seasonality over Northeast Asia.

关键词： tropospheric ozone photochemistry, stratospheric intrusion, jet stream activity, trajectory

The Schwarzian Derivative in Several Complex Variables

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Science China Mathematics 1993年第5期36卷 513-523页

作者：龚昇 Carl h.FitzGerald Department of Mathematics University of Science and Technology of China Hefei 230026 PRC Department of Mathematics University of California San Diego La Jolla CA 92093 USA

The Schwarzian derivative of holomorphic mappings on some classical domains is defined. Some Schwarzian properties are studied.

关键词： Sehwarzian derivative classical domains.

A Maximum Entropy Method Based on Orthogonal Polynomials for Frobenius-Perron Operators

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Advances in Applied Mathematics and Mechanics 2011年第2期3卷 204-218页

作者： Jiu Ding Noah h.Rhee Department of Mathematics The University of Southern MississippiHattiesburgMS 39406-5045USA Department of Mathematics and Statistics University of Missouri-Kansas CityKansas CityMO 64110-2499USA

Let S:[0,1]→[0,1]be a chaotic map and let f^(∗)be a stationary density of the Frobenius-Perron operator PS:L^(1)→L^(1)associated with *** develop a numerical algorithm for approximating f^(∗),using the maximum entropy approach to an under-determined moment problem and the Chebyshev polynomials for the stability *** experiments show considerable improvements to both the original maximum entropy method and the discrete maximum entropy method.

关键词： Frobenius-Perron operator stationary density maximum entropy orthogonal polynomials Chebyshev polynomials

historical development of the Gauss-Bonnet theorem

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Science China Mathematics 2008年第4期51卷 777-784页

作者： WU hung-hsi(h.Wu) Department of Mathematics University of California

A historical survey of the Gauss-Bonnet theorem from Gauss to Chern.

关键词： Gauss-Bonnet theorem Chern classes characteristic classes

Mitochondrial DNA analysis of human remains from the Yuansha site in Xinjiang, China

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Science China(Life Sciences) 2008年第3期51卷 205-213页

作者： Idelisi ABUDURESULE Victor h. MAIR Xinjiang Cultural Relics and Archaeology Institute Chinese Language and Literature Department of East Asian Languages and Civilizations University of Pennsylvania USA

The Yuansha site is located in the center of the Taklimakan Desert of Xinjiang, in the southern Silk Road region. MtDNA was extracted from fifteen human remains excavated from the Yuansha site, dating back 2,000―2,500 years. Analysis of the phylogenetic tree and the multidimensional scaling (mdS) reveals that the Yuansha population has relatively close relationships with the modern populations of South Central Asia and Indus Valley, as well as with the ancient population of Chawuhu.

关键词： Yuansha site ancient DNA mtDNA Xinjiang Central Asia

Mechanical Behavior of CrMo4 Steel With Dual-Phase Microstructure

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Journal of Iron and Steel Research(International) 2011年第S1期18卷 862-868页

作者： A Salemi A-h Golestaneh E Moosavi-Khoonsari Department of Metallurgy Engineering Islamic Azad University-Karaj BranchKarajIran Noor Behineh Gostar Co.Ltd.Tehran Iran

Multi-phase microstructures having good ductility may replace the conventional microstructures in different technological applications such as pressure *** properties including the fracture behavior and the service life of pressure vessels are strongly affected by the *** objective of this study was to investigate the correlation between different dual-phase microstructures and mechanical properties of 42CrMo4 (AISI 4140) *** produce the martensite-bainite (M-B),the martensite-ferrite (M-F),and the ferrite-bainite (F-B) microstructures,the step quenching heat treatment was *** properties of heat treated samples including the strength,ductility,and impact energy were *** experiments revealed a discontinuous yielding in the F-B specimen with ferritic ***\graphic results showed high concentration bright facets (BFs) on broken specimen surfaces indicating the brittle cleavage fracture was the predominant mechanism in the dual-phase microstructures.

关键词： 42CrMo4 steel dual-phase microstructures cleavage fracture

Esophagogastric junction distensibility assessed using the functional lumen imaging probe

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World Journal of Gastroenterology 2017年第7期23卷 1289-1297页

作者： Joan W Chen Joel h Rubenstein Department of Gastro-enterology and hepatology University of Michigan Health SystemsAnn ArborMI 48109United States

AIM To assess reference values in the literature for esophageal distensibility and cross-sectional area in healthy and diseased subjects measured by the functional lumen imaging probe(FLIP). METhODS Systematic search and review of articles in Medline and Embase pertaining to the use of FLIP in the esophagus was conducted in accordance with the PRISMA guidelines. Cross-sectional area and distensibility at the esophagogastric junction(EGJ) were abstracted for normal subjects, achalasia, and gastroesophageal reflux disease(GERD) patients, stratified by balloon length and volume of *** Six achalasia studies(n = 154), 3 GERD(n = 52), and 5 studies including healthy controls(n = 98) were included in the systematic review. Normative data varied widely amongst studies of healthy volunteers. In contrast, studies in achalasia patients uniformly demonstrated low point estimates in distensibility ≤ 1.6 mm2/mmh g prior to treatment that increased to ≥ 3.4 mm2/mmh g following treatment at 40 mL bag volume. In GERD patients, distensibility fell to the range of untreated achalasia(≤ 2.85 mm2/mm hg) following *** FLIP may be a useful tool in assessment of treatment efficacy in achalasia. The drastic drop in EGJ distensibility after fundoplication suggests that FLIP measurements need to be interpreted in the context of esophageal body motility and highlights the importance of pre-operative screening for dysmotility. Future studies using standardized FLIP protocol and balloon size are needed.

关键词：阻抗测面积池 Gastroesophageal 倒流疾病食道的膨胀性 Achalasia

Disorganization of the retinal inner layers as a prognostic factor in eyes with central retinal artery occlusion

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International Journal of Ophthalmology(English edition) 2019年第6期12卷 990-995页

作者： hayati Yilmaz Ali h.Durukan Department of Ophthalmology Mengucek Gazi Training and Research HospitalErzincan 24000Turkey Department of Ophthalmology Gulhane Medical FacultyAnkara 06010Turkey

AIM: To evaluate baseline foveal disorganisation of retinal inner layers(DRIL) as a prognostic factor in eyes with central retinal artery occlusion(CRAO). METhODS: Twenty-eight CRAO patients who were followed-up between 2010 and 2016 were retrospectively investigated. Demographic characteristics and detailed ophthalmological examination findings of all patients were recorded. Macular thicknesses(MTs) from 5 separate spots and DRIL were measured with spectral-domain optic coherence tomography(SD-OCT). Correlations between DRIL score and logMAR converted visual acuity(VA), change in VA, patient reference time(RT), number of hyperbaric oxygen therapy(hBOT) sessions, MT and MT change were ***: There was a positive correlation between the DRIL score and the final VA(r=0.787) and a negative correlation with the change in VA(r=-0.763). The RT and MT were closely related to the DRIL score. A negative correlation was found between the number of hBOT sessions and the DRIL score(r=-0.341).CONCLUSION: The DRIL score is a parameter assessed by SD-OCT, which can provide us reliable information regarding the prognosis of visual functions and response to the treatment for CRAO patients at acute phase.

关键词： central retinal artery occlusion disorganisation inner retina spectral-domain optic coherence tomography prognosis

Two perspectives of Listeria monocytogenes hazards in dairy products:the prevalence and the antibiotic resistance

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Food Quality and Safety 2019年第4期3卷 233-241页

作者： Beyza h.Ulusoy Kefyalew Chirkena Faculty of Veterinary Medicine Department of Food Hygiene and TechnologyNear East UniversityNicosiaCyprus

Listeria monocytogenes is among the most food-borne *** has the ability to grow over a range of temperature,including refrigeration *** kept in refrigerator more than the prescribed period of time create an opportunity for the occurrence of Listeria *** this review shows,the prevalence of *** has more likely evident in pasteurized milk than other dairy products,such as raw *** temperature and faults in technology during pasteurization can be the disposing factors for the presence of the organism in dairy *** organism,on the other hand,has been found to be resistant to those commonly known antibiotics that have human and veterinary importance,namely,ampicillin,Tetracycline,and chloramphenicol,streptomycin,erytromycin,penicillin G.,and *** ability of the organism can be mediated by different natural and acquired resistance mechanisms,such as self-transferrable plasmids,mobilizable plasmids,and conjugative *** emergence and spread of antibiotic resistance of *** has serious public health and economic impacts at *** paper has reviewed the prevalence and the antibiotic resistance of *** isolates of dairy products and the strategic mechanisms of the organism develop resistance against the antibiotics.

关键词： Listeria monocytogenes prevalence antibiotic resistance dairy products