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Journal of Rare Earths 2007年第6期25卷 670-673页

作者： g. Rijulal p. Indrasenan Department of Chemistry University of Kerala Kariavattom Campus Trivandrum-695 581 Kerala India

A series of seven novel lanthanide（Ⅲ ） nitrato complexes with 4-[ N-（2-methoxybenzylimine）formyl] 1-2, 3- dimethyl-1-phenyl-3-pyazolin-5-one （2mbfa）, were synthesized. These complexes were characterized by elemental analysis, molecular mass determination, conductance and magnetic moment measurements, IR, UV-visible, and ^13CNMR spectral studies, In these complexes, the Schiff base, 2mbfa, acts as neutral bidentate ligand by utilizing the carbonyl oxygen and azomethine nitrogen as donor sites. All the three nitrate ions are also coordinated unidentately with 7 coordination for the lanthanide（Ⅲ） ions with a tentative monocapped octahedral geometry for the complexes. All the seven lanthanide（Ⅲ） complexes have a general formula, [ Ln（2mbfa）：（NO3）3 ].

关键词： synthesis characterization lanthanide(Ⅲ) complexes Schiff bases rare earths

Studies on some lanthanide（Ⅲ） complexes with 4-hydroxyantipyrine

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Journal of Rare Earths 2008年第3期26卷 315-319页

作者： g. Rijulal p. Indrasenan Department of Chemistry University of Kerala Kariavattom Campus Trivandrum -695 581 Kerala India

Seven new lanthanide（Ⅲ） complexes with 4-hydroxyantipyrine were synthesized. These complexes were characterized by elemental analysis, molar conductance, magnetic moment measurements, FT-IR, electronic and 1HNMR spectra, X-ray powder diffraction, and thermogravimetric studies. The ligand, 4-hydroxyantipyrine （hap）, contained carbonyl oxygen and hydroxyl oxygen as potential donor sites. On coordination, deprotonation occurred and as a result, hap acted as a monobasic bidentate ligand. A coordination number 6 was assigned to the lanthanide（Ⅲ） ions in these complexes with orthorhombic structure. All the complexes were thermally stable-150℃ and underwent decomposition in three stages with the formation of Ln2O3 as the final residues.

关键词： synthesis lanthanide(Ⅲ) complexes 4-hydroxyantipyrine rare earths

A transmission electron microscopy study of microscopic causes for localized-corrosion morphology variations in the AA7055 Al alloy

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Journal of Materials Science & Technology 2018年第10期34卷 1719-1729页

作者： X.B. Yang J.H. Chen g.H. Zhang L.p. Huang T.w. Fan Y. Ding X.w. Yu Center for High-Resolution Electron Microscopy College of Materials Sdence and Engineering Hunan University Changsha Hunan 410082 China Department of Applied physics School of Physics and Electronics Hunan University Changsha Hunan 410082 China

By Using （scanning） transmission electron microscopy, localized-corrosion morphology variations of the AA7055 AIZn（Cu）Mg alloy with different thermal processes and their underlying microscopic causes were investigated systematically. Our study shows that the corrosion resistance of the nanoscale precipitates varies with their structure type and Cu-content. Just like the Al-matrix, the early-stage precipitates are corrosion resistant, as compared with the ηp/η-precipitates without high Cu-content. with a high Cu-content, however, the η-precipitates become most corrosion resistant among all phases involved. Hence, tailoring the precipitate microstructure and chemistry though thermal processes may change the overall corrosion morphology and improve corrosion resistance property of the alloy.

关键词： Aluminum alloys precipitates Corrosion Electron microscopy

Impact of extinction coefficient of phosphor on thermal load of color conversion elements of phosphor converted LEDs

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Journal of Rare Earths 2014年第3期32卷 201-206页

作者： F.p.wenzl p.Fulmek C.Sommer S.Schweitzer w.Nemitz p.Hartmann p.pachler H.Hoschopf F.Schrank g.Langer J.Nicolics Institute for Surface Technologies and photonics Joanneum Research Forschungsgesm.b.H. Franz-Pichler Stra?e 30 A-8160 Weiz Austria Institute of Sensor & Actuator Systems Vienna University of Technology Tridonic Jennersdorf gmbH Technologiepark 10 A-8380 Jennersdorf Austria Austria Technologie & Systemtechnik Ag Fabriksgasse 13 A-8700 Leoben Austria

Besides their direct impact on the respective correlated color temperature, the extinction coefficient and the quantum effi- ciency of the phosphor also have tremendous impact on the thermal load of the color conversion elements of phosphor converted LEDs under operation. Because of the low thermal conductivity of the silicone matrix in which the phosphor particles are typically embedded, the by far highest temperatures within the LED assembly are reached within the color conversion element. Based on a combined optical and thermal simulation procedure we show that in particular a larger value for the extinction coefficient might have a beneficial impact on the resulting thermal load.

关键词： light-emitting diode color conversion phosphor rare earths

REVIEw ON RESEARCH AND DEVELOpMENT OF MAgNESIUM ALLOYS

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Acta Metallurgica Sinica(English Letters) 2008年第5期21卷 313-328页

作者： Z. Yang J.p. Li J.X. Zhang g.w. Lorimer J. Robson Department of Materials Science and Engineering Xilan Jiaotong University Xilan 710049 China Department of Materials Science and Engineering Xi＇an Technological University Xi＇an 710032 China Manchester Materials Science Centre University of Manchester Manchester M 1 7HS UK

The current research and development of magnesium alloys is summarized. Several aspects of magnesium alloys are described： cast Mg alloy, wrought Mg alloy, and novel processing. The subjects are discussed individuall... 详细信息

关键词： Magnesium alloys Novel processing grain refined

Envelope Soliton in Solar Radio Emission

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Chinese physics Letters 2000年第5期17卷 355-357页

作者： wANg De-Yu g.p.Chernov purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 National Astronomical Observatories Chinese Academy of Sciences IZMIRAN 142092 TroitaskMoscow RegionRussia

Several envelope soliton fine structures have been observed in solar radio metric-wave *** a model of longitudinal modulational instability to explain these fine *** is found that this instability can only occur in the condition of sound velocity being larger than Alfvin velocity in ***,the envelope soliton fine structures should display in the coronal region with high temperature and low magnetic 6eld,which corresponds to the solar radio emission in the region of meter and decameter wavelength.

关键词： soliton envelope Soliton

JACQUES-LOUIS LIONS,1928-2001

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Chinese Annals of Mathematics,Series B 2002年第2期23卷 137-148页

作者： p.g.CIARLET Analyse Numerique Universite Pierre et Marie Curie

Jacques-Louis Lions was born in the heart of provence in the charming city of grasse,much renowned for its perfume industry and its historical *** spite of his young age, he had the courage and determination to join the FrenchResistance at the end of 1943, as a soldier in the FFI (French Forces of the Interior). Therehe met Andree, his wife and life-long companion.

关键词： Jacques-Louis-Lions 生平数学家法国应用数学变分不等式优化控制

Aerodynamic Sweeping Study and Design for Transonic Compressor Rotor blades

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Journal of Thermal Science 2010年第4期19卷 295-299页

作者： N.X.Chen,H.w.Zhang and w.g Huang Institute of Engineering Thermophysics,Chinese Academy of Sciences p.O.Box 2706 Beijing,100080,China Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China

The objective of the present paper is to study the sweep effect on the blade design performance of a transonic compressor *** baseline to be modified and swept is a designed well efficient transonic single rotor compressor. The first part of the present study is concerning the sweep effect with straight leading *** this case fixing the hub section the swept blade is formed by tilting the leading edge with whole blade forwards and backwards *** second part is to use an optimization strategy with simple gradient-based optimum-searching method and multi-section blade parameterization technique to search and generate an optimal swept rotor with curved arbitrary leading *** adiabatic efficiency is a little bit greater than that of the reference un-swept rotor.

关键词： Aerodynamic optimization blade sweep transonic compressor rotor

p systems with array objects and array rewriting rules

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progress in Natural Science:Materials International 2007年第4期17卷 479-485页

作者： K.g. Subramanian R. Saravanan M. geethalakshmi p. Helen Chandra M. Margenstern Department of Computer Science Sri Muthukumaran Institute of TechnologyChennai 600 069India Department of Mathematics Bharath Institute of Higher Education and ResearchChennai 600 073India Department of Mathematics Dr. MGR Janaki CollegeAdayarChennaiIndia Department of Mathematics Jayaraj Annapackiam College for Women Periyakulam 625 601India LITA Universite Paul Verlaine-MetzIle du Saulcy57045 Metz CedexFrance

Array p systems were introduced by paun gh. which is linking the two areas of membrane computing and picture grammars. puzzle grammars were introduced by us for generating connected picture arrays in the two-dimensional plane, motivated by the problem of tiling the plane. On the other hand, incorporating into arrays the developmental type of generation used in the well-known biologically motivated L systems, Siromoney and Siromoney proposed a very general rectangular array generating model, called extended controlled tabled L array system (ECTLAS). In this paper we introduce two variations of the array p system, called Bpg array p system and parallel array p system. The former has in the regions array objects and basic puzzle grammar rules (Bpg), which are a specific kind of puzzle grammar rules. In the latter, the regions have rectangular array objects and tables of context-free rules. we examine these two types of p systems for their array generative power.

关键词： membrane computing p systems array grammars.

Effects of the COVID-19 pandemic on semen quality in male partners of infertile couples: a hospitalbased observational study

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Asian Journal of Andrology 2023年第2期25卷 240-244页

作者： Tribhuwan Kumar Kamlesh Jha Md Zabihullah kumari Neelu Yogesh Kumar Kumar Siddharth Department of physiology All India Institute of Medical SciencesPatna 801507BiharIndia Akshat Spandan Clinic Patna 801507BiharIndia

The effects of the coronavirus disease 2019(COVID-19)pandemic on male fertility have received considerable attention because human testes contain high levels of angiotensin-converting enzyme-2 receptors,through which severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)can *** studies showed decreases in semen quality during and after recovery from ***,no semen quality studies have examined the effects of widespread subclinical and mild disease,as well as changes in lifestyle,psychosocial behavior,intake of dietary supplements,and *** cross-sectional study compared semen quality parameters in male partners of infertile couples between men who underwent semen analysis before the COVID-19 pandemic(prepandemic group)and men who underwent semen analysis during the pandemic period(pandemic group);the analysis sought to clarify the overall effects of the *** participants in the pandemic group had experienced clinically overt *** the 239 participants,mean body weight(p=0.001),mean body mass index(pperm concentration(p=0.014),total sperm count(p=0.006),and total percentages of motile(p=0.013)and abnormal cells(pwere significantly greater in the pandemic group(n=137)than those in the prepandemic group(n=102).Among abnormal cells,the percentages of cells with excess residual cytoplasm(ppp=0.015)were significantly greater in the pandemic group than those in the prepandemic *** the exception of morphology,the overall semenogram results were better in the pandemic group than those in the prepandemic group.

关键词： coronavirus disease 2019 pandemic male infertility SARS-CoV-2 semen analysis