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Open Journal of Physical Chemistry 2022年第3期12卷 31-45页

作者： mariette desiree Yehe frédérique yah marie-pierre nikiema Linda Hé Vincent de Paul Ovi Jean-Kisito Kouame Patrick Grah Atheba Gildas Komenan Gbassi department of Analytical Sciences and Public Health UFR of Pharmaceutical and Biological Sciences (UFR SPB) Félix Houphou&#235 t Boigny University Abidjan Ivory Coast National Public Health Laboratory Food Control Service Abidjan Ivory Coast Félix Houphouë t Boigny University Laboratory of Analytical Chemistry Bromatology General Chemistry and Inorganic Chemistry Abidjan Ivory Coast

The present work aims to study the influence of some physicochemical parameters (light, temperature, ethanol, bile salts, potassium hydroxide, hydrogen peroxide) on the content of Metronidazole (MTZ) contained in the reference substance (SR) and in a pharmaceutical specialty Flagyl® 250 mg tablet (FLG). The method developed was linear and accurate in accordance with USP 38 and the MTZ contents were obtained by UV-visible spectrophotometry at 278 nm. These contents ranged from 225 mg to 275 mg and were thus consistent with the concentration present in the proprietary medicines (250 mg). The study of the influence of physicochemical parameters on the MTZ content in SR and FLG showed that MTZ contents are unstable in the presence of Ethanol at 96˚, KOH at 0.1N and bile salts but also when the temperature is higher than 25˚C. However, they remain stable in the presence of light and H2O2 and undergo degradation in an acidic environment.

关键词： Metronidazole Influence Physicochemistry Content Stability

Influence of Some Physicochemical Exposure Factors on the Metronidazole Content of a Pharmaceutical Product: Flagyl® 250 mg Tablet

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A case of post traumatic mitral chordae rupture mimicking acute respiratory distress syndrome

Open Journal of Physical Chemistry（物理化学期刊） 2022年第3期

作者： mariette desiree Yehe frédérique yah marie-pierre nikiema LindaHé Vincent de Paul Ovi Jean-Kisito Kouame Patrick Grah Atheba Gildas Komenan Gbassi

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World Journal of Emergency Medicine 2024年第4期15卷 322-324页

作者： Hülya deniz Misir Nalan demir Ferit Kasimzade Cansu yahşi Intensive Care department Ankara Bilkent City HospitalAnkara 06800Turkiye Intensive Care department University of Health Sciences Ankara Bilkent City HospitalAnkara 06800Turkiye Cardiovascular Surgery department Ankara Bilkent City HospitalAnkara 06800Turkiye Pulmonary Medicine department University of Health Sciences Ankara Bilkent City HospitalAnkara 06800Turkiye

Traumatic mitral chordae rupture is a rare and known cause of acute mitral valve regurgitation and de novo heart *** pathologies in a trauma patient may mask the findings of de novo heart failure due to mitral chordae *** patients may also have other potential pre-diagnoses that could explain symptoms related to heart failure,such as tachycardia,circulatory shock,and acute *** possibility of traumatic chordae tendinea rupture being a preventable cause of mortality should be carefully evaluated.

关键词： rupture mitral acute

Semiparametric Additive Intensity Model with frailty for Recurrent Events

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Acta Mathematica Sinica,English Series 2011年第9期27卷 1831-1842页

作者： yah yah LIU Yuan Shan WU School of Mathematics and Statistics Wuhan University Wuhan 430072 P. R. China

The seminal Cox＇s proportional intensity model with multiplicative frailty is a popular approach to analyzing the frequently encountered recurrent event data in scientific studies. In the case of violating the proportional intensity assumption, the additive intensity model is a useful alternative. Both the additive and proportional intensity models provide two principal frameworks for studying the association between the risk factors and the disease recurrences. However, methodology devel- opment on the additive intensity model with frailty is lacking, although would be valuable. In this paper, we propose an additive intensity model with additive frailty to formulate the effects of possibly time-dependent covariates on recurrent events as well as to evaluate the intra-class dependence within recurrent events which is captured by the frailty variable. The asymptotic properties for both the regression parameters and the association parameters in frailty distribution are established. Fhrthermore, we also investigate the large-sample properties of the estimator for the cumulative baseline intensity function.

关键词： Additive intensity model counting process donsker class frailty recurrent events

FATIGUE GROWTH MOdELING OF MIXEd-MOdE CRACK IN PLANE ELASTIC MEdIA

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Acta Mechanica Solida Sinica 2005年第3期18卷 234-241页

作者： yah Xiangqiao Research Laboratory of Composite Materials Harbin Institute of Technology Harbin 150001 China

This paper presents an extension of a displacement discontinuity method with cracktip elements （a boundary element method） proposed by the author for fatigue crack growth analysis in plane elastic media under mixed-mode conditions. The boundary element method consists of the non-singular displacement discontinuity elements presented by Crouch and Starfield and the crack-tip displacement discontinuity elements due to the author. In the boundary element implementation the left or right crack-tip element is placed locally at the corresponding left or right crack tip on top of the non-singular displacement discontinuity elements that cover the entire crack surface and the other boundaries. Crack growth is simulated with an incremental crack extension analysis based on the maximum circumferential stress criterion. In the numerical simulation, for each increment of crack extension, remeshing of existing boundaries is not required because of an intrinsic feature of the numerical approach. Crack growth is modeled by adding new boundary elements on the incremental crack extension to the previous crack boundaries. At the same time, the element characteristics of some related elements are adjusted according to the manner in which the boundary element method is implemented. As an example, the fatigue growth process of cracks emanating from a circular hole in a plane elastic plate is simulated using the numerical simulation approach.

关键词： boundary element method mixed-mode crack fatigue crack growth displacement discontinuity crack-tip element

Stochastic Perturbations of Fat Solenoidal Attractors

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Acta Mathematica Sinica,English Series 2010年第5期26卷 923-936页

作者： yah ZHENG department of Mathematics National University of Defense Technology Changsha 410073 P. R. China

In this article stochastic perturbations of a class of fat solenoidal attractors are considered. We show the robustness of their invariant densities and rates of mixing under the stochastic perturbations by investigat... 详细信息

关键词： fat solenoidal attractors stochastic perturbations Sinai-Ruelle-Bowen measures

Oxidation of NiAl-Ag Alloys at 1000℃ in 0.1 MPa O_(2)

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Journal of Materials Science & Technology 2005年第4期21卷 489-492页

作者： Xuejun ZHANG yah NIU State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China Shenyang Institute of Chemical Technology Shenyang 110142 China

Small amounts of silver have been added to the intermetallic compound NiAl with the purpose of improving its mechanical properties. Four ternary NiAl-Ag alloys containing 0.5, 1, 5 and 10 at. pct Ag, denoted as ***,NiAl-1Ag, NiAl-5Ag and NiAl-10Ag, and the Ag-free NiAl have been oxidized at 1000℃ for 24 h in 0.1 MPa O2 to study the effect of the presence of silver on the oxidation behavior of NiAl. All the NiAl-Ag alloys are composed of a matrix of β-NiAl containing a dispersion of isolated particles of a second silver-rich phase. A continuous external layer of Al2O3 formed on all the alloys. In addition, the scales formed on NiAl-5Ag contained a thin and discontinuous layer of pure silver located at the alloy/Al2O3 interface, while those formed on NiAl-10Ag contained isolated particles as well as discontinuous layers of silver at various locations in the scale extending up to the gas/scale interface. The kinetic curves of all the alloys were generally composed of two main parabolic stages with smaller parabolic rate constants for the final stage. The addition of silver does not significantly affect the oxidation behavior of the NiAl intermetallic compound in all cases, as expected because silver is essentially present only as a second phase due to its very small solubility in β-NiAl.

关键词： NiA1-Ag Ternary alloys Oxidation

Embedding generalized of circulant graphs and Petersen graphs on projective plane

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frontiers of Mathematics in China 2015年第1期10卷 209-220页

作者： yah YANG Yanpei LIU department of Mathematics Tianjin University Tianjin 300072 China department of Mathematics Beijing Jiaotong University Beijing 100044 China

Both the circulant graph and the generalized Petersen graph are important types of graphs in graph theory. In this paper, the structures of embeddings of circulant graph C（2n ＋ 1; {1, n}） on the projective plane are described, the number of embeddings of C（2n ＋ 1; {1, n}） on the projective plane follows, then the number of embeddings of the generalized Petersen graph P（2n ＋ 1, n） on the projective plane is deduced from that of C（2n ＋ 1; {1, n}）, because C（2n ＋ 1; {1, n}） is a minor of P（2n ＋ 1, n）, their structures of embeddings have relations. In the same way, the number of embeddings of the generalized Petersen graph P（2n, 2） on the projective plane is also obtained.

关键词： Embedding joint tree circulant graph generalized Petersen graph,projective plane

Constructions of optimal variable-weight OOCs via quadratic residues

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frontiers of Mathematics in China 2013年第4期8卷 869-890页

作者： yah LIU dianhua WU department of Mathematics Guangxi Normal University Guilin 541004 China

Variable-weight optical orthogonal code （OOC） was introduced by G. C. Yang [IEEE Trans. Commun., 1996, 44： 47-55] for multimedia optical CdMA systems with multiple quality of service （QoS） requirements. In this p... 详细信息

关键词： Cyclic packing optical orthogonal code (OOC) quadratic residue relative difference family variable-weight OOC

Influence of an emulsifier on the pressure desensitization of emulsion explosives

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Journal of University of Science and Technology Beijing 2006年第2期13卷 102-107页

作者： Yinjun Wang Xuguang Wang Shilong yah Civil ＆ Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China Beijing General Research Institute of Mining and Metallurgy Beijing 100044 China Chemical Engineering department Anhui University of Science and Technology Anhui 232001 China

The desensitization degree of emulsion explosives （EE） was calculated with the peak pressure of explosion shock waves tested in water. To an explosive, the less the desensitization degree, the better the compression resistance, so the compression resistance of an explosive can be compared and analyzed quantificationally with the desensitization degree. The influence of an emulsifier on the pressure desensitization of EE was studied, including the content and category of emulsifiers. Three kinds of emulsifiers （Span-80, compound emulsifier, and T-152） were used in the tests. The experimental results show that both the content and category of emulsifiers make a great effect on the pressure desensitization of EE. The desensitization degree of EE reduces with the emulsifier content being increased, but there is an optimal content of an emulsifier for the compression resistance of EE. While the content of Span-80 reaches 4wt%, the desensitization degree of EE becomes a minimal value, and augments somewhat if the emulsifier content is increased more. That is to say, the compression resistance of EE becomes the highest while the content of Span-80 is 4wt%, and the compression resistance will decline if the content of Span-80 is increased more. The compression resistance of the explosive emulsified by compound emulsifier is the highest among all the explosives, when the content of the whole components and manufacturing engineering are kept invariable.

关键词： emulsion explosive emulsifier pressure desensitization shock wave compression resistance