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Development and characterization of 3CaO·P_(2)O_(5)-SiO_(2)-MgO glass-ceramics with different crystallization degree

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Journal of Advanced Ceramics 2013年第4期2卷 378-388页

作者： Juliana Kelmy M.f.DAGUANO Paulo A.SUZUKI Kurt STRECKER JoséMartinho Marques de OLIVEIRA Maria Helena figueira Vaz fERNANDES Claudinei SANTOS Universidade de São Paulo-Escola de Engenharia de Lorena USP-EEL-Pólo Urbo-Industrials/nGleba AI-6Lorena-SPCEP 12600-000Brazil Universidade federal de São João del-Rei -UFSJ-CENENCampus S^(to)Antônio-Praça Frei Orlando 170-CentroS.J.del-Rei-MG.CEP 36307-352Brazil Escola Superior Aveiro Norte Edifício Rainha3720-232 O.AzeméisPortugal Universidade de Aveiro Campus Universitário de Santiago 3810-193 AveiroPortugal Universidade do Estado do Rio de Janeiro-faculdade de Tecnologia de Resende-UERJ-fAT-Rod.Presidente Dutra km298Resende-RJCEP 27537-000Brazil

The CaO-P_(2)O_(5)-SiO_(2)-MgO system presents several compounds used as biomaterials such as hydroxyapatite(HA),tricalcium phosphate(TCP)and TCP with magnesium substituting partial calcium(TCMP).Theβ-TCMP phase with whitlockite structure has interesting biological features and mechanical properties,meeting the requirements of a bioactive material for bone *** this work,the production of Mg-doped TCP,β-TCMP,has been investigated by crystallization from a glass composed of 52.75 wt%3CaO·P_(2)O_(5),30 wt%SiO_(2)and 17.25 wt%MgO(i.e.,31.7 mol%CaO,10.6 mol%P_(2)O_(5),26.6 mol%MgO and 31.1 mol%SiO_(2))using heat treatments between 775℃and 1100℃for up to 8 *** devitrification process of the glass has been accompanied by differential scanning calorimetry(DSC),high-resolution X-ray diffraction(HRXRD),relative density and bending strength *** characterization by HRXRD and DSC revealed the occurrence of whitlockite soon after the bulk glass preparation,a transient non-cataloged silicate between 800℃and 1100℃,and the formation of diopside in samples treated at 1100℃as crystalline *** overall crystalline fraction varied from 26%to 70%depending on the heat ***,contraction of the a-axis lattice parameter and expansion of the c-axis lattice parameter of the whitlockite structure have been observed during the heat treatments,which were attributed to theβ-TCMP formation with the partial substitution of Ca^(2+)by Mg^(2+).Relative densities near 99%and 97%for the glass and glass-ceramics respectively indicated a discrete reduction as a function of the devitrification *** strengths of 70 MPa and 120 MPa were determined for the glass and glass-ceramic material crystallized at 975℃for 4 h,respectively.

关键词： glass-ceramics heat treatment high-resolution X-ray diffraction(HRXRD) bending strength

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ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY DURING CORROSION PROCESS Of 8090 Al-Li ALLOY IN EXCO SOLUTION

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Acta Metallurgica Sinica(English Letters) 2004年第6期17卷 894-901页

作者： J.f.Li Z.Q.Zheng C.Y.Tan S.C.Li Z.Zhang J.Q.Zhang CollegeofMaterialsScienceandEngineering CentralSouthUniversityChangsha410083China／／DepartmentofChemistryZhejiangUniversityHangzhou310027China CollegeofMaterialsScienceandEngineering CentralSouthUniversityChangsha410083China DepartmentofChemistry ZhejiangUniversityHangzhou310027China DepartmentofChemistry ZhejiangUniversityHangzhou310027China／／StateKeyLaboratoryforCorrosionand.ProtectionInstituteofMetalResearchTheChineseAcademy

The corrosion behavior and electrochemical impedance spectroscopy (EIS) features of 8090 Al-Li alloys in EXCO solution were investigated, and the EIS was simulated using an equivalent circuit. At the beginning of immersion in EXCO solution, the EIS is comprised by a depressed capacitive arc at high-mediate frequency and an inductive arc at low frequency, and the inductive component decreases and disappears with im- mersion time. Once exfoliation or severe pitting corrosion is produced, two capacitive arcs appear in the EIS. These two capacitive arcs are originated from the two parts of the corroded alloy surface, the original flat alloy surface and the new inter-face exposed to the aggressive EXCO solution due to the exfoliation or pitting corrosion. Some corrosion development features of 8090 Al-Li alloys in EXCO solution can be obtained through simulated EIS information.

关键词： Al-Li alloy, exfoliation, electrochemical impedance spectros- copy (EIS), EXCO solution

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Application of light sheet microscopy for qualitative and quantitative analysis of bronchus-associated lymphoid tissue in mice

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Cellular & Molecular Immunology 2018年第10期15卷 875-887页

作者： David Twapokera Mzinza Henrike fleige Kristin Laarmann Stefanie Willenzon Jasmin Ristenpart Julia Spanier Gerd Sutter Ulrich Kalinke Peter Valentin-Weigand Reinhold förster Institute of Immunology Hannover Medical SchoolHannoverGermany Institute for Microbiology University of Veterinary Medicine HannoverHannoverGermany Institute for Experimental Infection Research TWINCORECentre for Experimental and Clinical Infection Researcha joint venture between the Helmholtz-Centre for Infection Research and the Hannover Medical SchoolHannoverGermany Institute for Infectious Diseases and Zoonoses University of Munich LMUMunichGermany

Bronchus-associated lymphoid tissue(BALT)develops at unpredictable locations around lung bronchi following pulmonary *** formation and composition of BALT have primarily been investigated by immunohistology that,due to the size of the invested organ,is usually restricted to a limited number of histological *** assess the entire BALT of the lung,other approaches are urgently ***,we introduce a novel light sheet microscopy-based approach for assessing lymphoid tissue in the *** antibody staining of whole lung lobes and optical clearing by organic solvents,we present a method that allows in-depth visualization of the entire bronchial tree,the lymphatic vasculature and the immune cell composition of the induced ***,three-dimensional analysis of the entire lung allows the qualitative and quantitative enumeration of the induced *** this approach,we show that a single intranasal application of the replication-deficient poxvirus MVA induces BALT that constitutes up to 8%of the entire lung volume in mice deficient in CCR7,in contrast to wild type mice(WT).furthermore,BALT induced by heat-inactivated *** is dominated by a pronounced T cell infiltration in Cxcr5-deficient mice,in contrast to WT mice.

关键词： Lung BALT light sheet microscopy E.coli MVA

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Plant communities and reproductive phenology in mountainous regions of northern Libya

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Journal of forestry Research 2017年第4期28卷 741-761页

作者： Ahmad K. Hegazy Hanan f. Kabiel Saud L. Al-Rowaily Lesley Lovett-Doust Abd El-Nasser S. Al Borki Department of Botany and Microbiology Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Plant Production College of Food and Agricultural SciencesKing Saud UniversityRiyadhSaudi Arabia Department of Biology and Chemistry Nipissing UniversityNorth BayONCanada Department of Botany Faculty of Sciences and ArtsUniversity of BenghaziAgdabiaLibya

Within the semi-desert landscape of northern Libya, two sub-humid escarpments occur: Al-Akhdar in the east and Nafusa (Jabal Al-Gharbi) in the west. This study compares plant communities in the two regions, which are along an elevation gradient, in terms of species composition and diversity, frequency of different Raunkiaer life forms, and reproductive phenology. The two regions differed in species composition and life-form frequency between regions and between elevation zones within each region. Patterns were associated with the lower rainfall and lower moisture-holding capacity of soils at Nafusa, resulting in more xeric conditions. Only 13% of species were shared between the two regional landscapes. Species diversity, life-form frequency, and duration of the flowering-fruiting phenophase were all affected by elevation above sea level. The duration of flowering and fruiting in spring and fall was associated with environmental conditions, although there were different thresholds in the two regions. There was both a spring and fall episode of flowering at Nafusa, but only spring flowering at Al-Akhdar. It is anticipated that there will be a gradual shift of plant communities to higher elevations and loss of certain sensitive species in response to ongoing climate change.

关键词： Altitudinal gradient Raunkiaer life forms Reproductive phenology Southern Mediterranean

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Raman-IR vibrational and XRD characterization of ancient and modern mineralogy from volcanic eruption in Tenerife Island： Implication for Mars

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Geoscience frontiers 2016年第4期7卷 673-681页

作者： E.A.Lalla G.Lopez-Reyes A.Sansano A.Sanz-Arranz j.Martinez-frias J.Medina f.Rull-Perez department of physics faculty of science university of la laguna san cristobal de la laguna santa cruz de tenerifeCP 38206 spain Unidad Asociada al Centro de Astrobiologfa CSIC-INTA Associated to the NASA Astrobiology Center-Instituto Nacional de Tecnica Aeroespacial Torrejon de ArdozCP 28850MadridSpain Department of Earth Dynamics and Observation lnstituto de Ceociencias IGEO-(CSIC-UCM)Facultad de Ciencias Geologicas.Ciudad UniversitariaCP 28040MadridSpain

A detailed vibrational Raman-lR spectroscopic and diffractional analyses have been performed on basalts from two locations from Tenerife Island：（1） the Arenas Negras volcano which belongs to the historical eruption not showing visible alteration and （2） Pillow Lavas zone from Anaga Massif which shows a clearly fluid-rock interaction caused by submarine alteration. These places have been extensively studied due to its similarity with the surface of Mars. The analysis is based on the mineral detection of selected samples by a Micro-Raman study of the materials. The complementary techniques have confirmed the mineralogy detected by the Raman measurement. The results show a volcanic environment behavior with primary phases like olivine, pyroxene, and feldsparJplagioclase. Moreover, the presence of accessory minerals or secondary mineralization like phosphate, iron oxides, zeolite or carbonates shows the alteration processes on each outcrop. The variation in the crystallinity and amorphous phases is related to fluid-rock interaction caused by hydrothermal episodes and external weathering processes, which shows several analogies with the ancient volcanic activity from Mars.

关键词： Mars Volcanoes Terrestrial analog Raman spectroscopy Tenerife Island Mineralogy

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全球鹦鹉入侵

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环球科学 2023年第15期 38-47页

作者：瑞安·f.曼德尔鲍姆吕昀斐(译) 王梓峰(审校) 不详

在美国纽约布鲁克林的绿荫公墓中,生者受到的关注与死者一样多。这里的场地管理员将这片约两平方千米的历史地标当作植物园,以及200多种繁殖与迁鸟类的栖息地来维护。但许多来访的野生动物爱好者对这里的本地鸟类并不感兴趣。他们站在... 详细信息

在美国纽约布鲁克林的绿荫公墓中,生者受到的关注与死者一样多。这里的场地管理员将这片约两平方千米的历史地标当作植物园,以及200多种繁殖与迁鸟类的栖息地来维护。但许多来访的野生动物爱好者对这里的本地鸟类并不感兴趣。他们站在入口处,手中的双筒望远镜对准了绿荫公墓哥特复兴式拱门上的尖顶他们是来看鹦鹉的。

关键词：双筒望远镜植物园鹦鹉野生动物布鲁克林栖息地公墓美国纽约

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Implementation of a faraday rotation diagnostic at the OMEGA laser facility

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High Power Laser Science and Engineering 2018年第3期6卷 102-111页

作者： A.Rigby J.Katz A.f.A.Bott T.G.White P.Tzeferacos D.Q.Lamb D.H.froula G.Gregori Department of Physics University of Oxford Parks Road Oxford OX1 3PU UK Laboratory for Laser Energetics University of Rochester 250 E. River Rd Rochester NY 14623 USA Department of Physics University of Nevada Reno NV 89557 USA Department of Astronomy and Astrophysics University of Chicago 5640 S. Ellis Ave Chicago IL 60637 USA

Magnetic field measurements in turbulent plasmas are often difficult to perform. Here we show that for kG magnetic fields, a time-resolved faraday rotation measurement can be made at the OMEGA laser facility. This diagnostic has been implemented using the Thomson scattering probe beam and the resultant path-integrated magnetic field has been compared with that of proton radiography. Accurate measurement of magnetic fields is essential for satisfying the scientific goals of many current laser–plasma experiments.

关键词：湍流等离子体磁场激光技术激光装置

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Influence of physical and chemical factors during foraging and culture of the symbiont fungus in Atta sexdens rubropilosa （Hymenoptera： formicidae）

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Insect Science 2007年第4期14卷 295-300页

作者： SANDRA S. VERZA LUIZ C. fORTI JULIANE f. S. LOPES ROBERTO S.CAMARGO CARLOS A. O. MATOS Departamento de Zoologia Instituto de Biociencias Laboratrio de Insetos Sociais-Praga Departamento de Produ~~o Vegetal-Def-esa Fitossanitaria Faculdade de Ciencias Agronomicas UNESP-Sao Paulo State University Fazenda Experimental LageadoBotucatu SP Comportamento e Biologia Animal Instituto de Ciencias Biologicas UFJF-Universidade Federal de Juiz de ForaCampus Universitario Martelos Juiz de Fora MG Campus Experimental de Itapeva UNESP Itapeva SP Brazil

The aim of this paper is to investigate the influence of physical and chemical factors on transport and use of substrate for Atta sexdens rubropilosa workers. Three types of rectangular fragments were used to study the physical influence factors： filter paper with paraffin, filter paper without paraffin and polyester film. To study the chemical factors, some fragments were impregnated with organic extract of orange albedo, others were soaked with soybean oil and for the remaining ones nothing was applied. The fonowing parameters were evaluated：（i） attractiveness of substrate for transport and number of loading workers per treatment; （ii） foraged material incorporation; （iii） rejection by numbers of fragments deposited in the garbage or beside the fungus garden. All the polyester film fragments carried out to the fungus garden were subsequently rejected. We verified that chemical factors of the substrate were more quickly detected by the workers, whereas physical factors were used as a criterion in the decision-making to reject or accept the substrate collected.

关键词： Atta sexdens rubropilosa attractiveness behavior leaf-cutting ants substraterejection substrate selection

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TRIBOLOGICAL AND HIGH SPEED TURNING PERfORMANCE IN Ti_(1-x)Al_(x)N COATINGS PREPARED BY CLOSE-fIELD UNBALANCED MAGNETRON SPUTTERING

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 254-260页

作者： P.W.Shum M.Escursell T.H.Wong K.Y.Li Z.f.Zhou Y.G.Shen Advanced Coatings Applied Research Laboratory(ACARL) Department of Manufacturi ng Engineering and Engineering ManagementCity University of Hong KongKowloonHong KongChina

Titanium-aluminium-nitride(Ti_(1-x)Al_(x)N)coatings were deposited by close-field un balanced magnetron sputtering on M42 steel substrates and WC-6wt%Co inserts at 450℃.The tribological behavior was analyzed by sliding against steel and WC-6wt%Co balls,while the turning performance was evaluated by a conventional tu rning machine at high cutting speeds without using *** the tribological tests,the formation of transfer layer and the variations of hardness of the co atings played an important role for sliding against steel *** the coating s sliding against WC-6wt%Co balls,the Ti-Al-N coatings showed a similar frictio n coefficient,but the TiN coating exhibited a lower *** difference could be explained by the tri-oxidation wear *** the turning tests,a super ior cutting performance of the coating was found at x=0.45,which endured 38 min utes before the tool flank wear reached the maximum value of 0.3mm,whereas only 20 minutes were endured for the TiN *** excellent performance of the c oatings in the turning tests could be explained by the enhanced mechanical prope rties and oxidation/diffusion resistance of the coatings.

关键词： hardness Ti-Al-N coating tribology turning test wear test

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Circular smooth muscle contributes to esophageal shortening during peristalsis

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World Journal of Gastroenterology 2012年第32期18卷 4317-4322页

作者： Anil K Vegesna Keng-Yu Chuang Ramashesai Besetty Steven J Phillips Alan S Braverman Mary f Barbe Michael R Ruggieri Larry S Miller Department of Medicine Section of GastroenterologyHofstra Northshore Long Island Jewish HospitalHofstra University School of MedicineManhassetNY 11030United States Department of Medicine Section of GastroenterologyTemple University School of MedicinePhiladelphiaPA 19140United States Department of Anatomy and Cell Biology Temple University School of MedicinePhiladelphiaPA 19140United States Department of Urology Temple University School of MedicinePhiladelphiaPA 19140United States Department of Anatomy and Cell Biology and Department of Urology Temple University School of MedicinePhiladelphiaPA 19140United States

AIM:To study the angle between the circular smooth muscle(CSM) and longitudinal smooth muscle(LSM) fibers in the distal ***:In order to identify possible mechanisms for greater shortening in the distal compared to proximal esophagus during peristalsis,the angles between the LSM and CSM layers were measured in 9 *** outer longitudinal layer of the muscularis propria was exposed after stripping the outer *** inner circular layer of the muscularis propria was then revealed after dissection of the esophageal mucosa and the underlying muscularis *** of each specimen were taken with half of the open esophagus folded back showing both the outer longitudinal and inner circular muscle *** were measured every one cm for 10 cm proximal to the squamocolumnar junction(SCJ) by two independent *** human esophagi were obtained from organ transplant donors and the angles between the circular and longitudinal smooth muscle layers were measured using micro-computed tomography(micro CT) and Image J ***:All data are presented as mean ± *** CSM to LSM angle at the SCJ and 1 cm proximal to SCJ on the autopsy specimens was 69.3 ± 4.62 degrees vs 74.9 ± 3.09 degrees,P = *** CSM to LSM angle at SCJ were statistically significantly lower than at 2,3,4 and 5 cm proximal to the SCJ,69.3 ± 4.62 degrees vs 82.58 ± 1.34 degrees,84.04 ± 1.64 degrees,84.87 ± 1.04 degrees and 83.72 ± 1.42 degrees,P = 0.013,P = 0.008,P = 0.004,P = 0.009 *** CSM to LSM angle at SCJ was also statistically significantly lower than the angles at 6,7 and 8 cm proximal to the SCJ,69.3 ± 4.62 degrees vs 80.18 ± 2.09 degrees,81.81 ± 1.75 degrees and 80.96 ± 2.04 degrees,P = 0.05,P = 0.02,P = 0.03 *** CSM to LSM angle at 1 cm proximal to SCJ was statistically significantly lower than at 3,4 and 5 cm proximal to the SCJ,74.94 ± 3.09 degrees vs 84.04 ± 1.64 degrees,84.87 ± 1.04 degrees and 83.72 ± 1.42 degrees,P =

关键词：平滑肌食管蠕动计算机断层扫描圆形 CSM LSM 角度测量

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