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A Study of Making Iron Aluminide Alloy Powders with New Rotating Electrode Technology

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厦门大学学报（自然科学版） 2002年第S1期41卷 107-108页

作者： S S lIAN M l SHI Department of Materials Science & Engineering National Taiwan UniversityDepartment of Materials Science & Engineering National Taiwan University Taipei ChinaTaipei China

A new process was used for producing FeAl alloy pow de rs with double consumable rotating electrodes and the powders made in this appar atus were analyzed. In this new technology, tungsten rod serves as a cathode ele ctrode, while the alloy rod as an anode electrode. The conventional rotating ele ctrode process must have an anode with pre-melting alloys; however, in this new process, using pure iron as cathode electrode and pure aluminum as anode electr ode can eliminate the step of pre-melting. The effects of process variables, which include electrode rotational speed, a nd electrode diameter of the mean particle diameter were determined. Results showed that both the rotational speed and diameter of electrodes would a ffect the mean diameter of particles. There are three kinds of powders with diff erent composition produced in this study and the possible mechanisms are discuss ed. The process parameters and volume mean diameter of the powders have been cor related to find an experimental equation. The results show that when the rotational speed and the diameter of the anode el ectrode are increased, the powders size will decrease. However, the powders size will increase with cathode electrode.

关键词： A Study of Making Iron Aluminide Alloy Powders with New Rotating Electrode Technology

Hypospadias： an update

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Asian Journal of Andrology 2007年第1期9卷 16-22页

作者： Alexander K. C. leung William l. M. Robson Department of Pediatrics The University of Calgary Calgary Alberta T2M 0H5 Canada The Alberta Children＇s Hospital Calgary Alberta T2M 0H5 Canada The Childrens＇ Clinic Calgary Alberta T2M 0H5 Canada

Hypospadias is the most common congenital anomaly of the penis. The problem usually develops sporadically and without an obvious underlying cause. The ectopically positioned urethral meatus lies proximal to the normal site and on the ventral aspect of the penis, and in severe cases opens onto the scrotum or perineum. The foreskin on the ventral surface is deficient, while that on the dorsal surface is abundant, giving the appearance of a dorsal hood. Chordee is more common in severe cases. Cryptorchidism and inguinal hernia are the most common associated anomalies. The frequency of associated anomalies increases with the severity of hypospadias. For isolated anterior or middle hypospadias, laboratory studies are not usually necessary. Screening for urinary tract anomalies should be considered in patients with posterior hypospadias and in those with an anomaly of at least one additional organ system. The ideal age for surgical repair in a healthy child is between 6 and 12 months of age. Most cases can be repaired in a single operation and on an outpatient basis. Even patients with a less than perfect surgical result are usually able to enjoy a satisfactory sexual life.

关键词： hypospadias sporadic cryptorchidism inguinal hernia renal anomaly repair

MODElING OF 'BANDING' MICROSTRUCTURE FORMATION IN CENTRIFUGAllY SOlIDIFIED Ti-6Al-4V AllOY

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Acta Metallurgica Sinica(English letters) 2008年第6期21卷 399-408页

作者： D.R. liu E：J. Guo l.P. Wang School of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Numerical investigations of the ＇banding＇ microstructure formation during solidification of Ti-6Al-4 V alloy in the centrifugal casting are conducted using a multi-scale model, which combines the finite difference method （FDM） at the macroscale with a cellular automaton （CA） model at the microscale. The macro model is used to simulate the fluid flow and heat transfer throughout the casting. The micro model is used to predict the nucleation and growth of microstructures. With the proposed model, numerical simulations are performed to study the influences of the nucleation density, mould rotation speed, and casting size upon the ＇banding＇ microstructure formation. It is noted that changing the nucleation density has a minor effect on the microstructure formation. The rotation speed promotes the formation of ＇banding＇ microstructure, which is more noticeable for larger size castings. The ＇major mechanism responsible for this ＇banding＇ phenomenon is the spatial variation in cooling rates created by centrifugal force.

关键词： Modeling 'Banding' microstructure Ti-6Al-4V alloy Centrifugal casting

S-doped carbon aerogels/GO composites as oxygen reduction catalysts

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Journal of Energy Chemistry 2016年第2期25卷 234-243页

作者： Mykola Seredych Krisztina lászló Enrique Rodríguez-Castellón Teresa J.Bandosz The City College of New York and The Graduate Center of CUNY Department of Chemistry 160 Convent Avenue New York NY 10031 USA Department of Physical Chemistry and Materials Science Budapest University of Technology and Economics Budapest 1521 Hungary Departamento de Quimica Inorganica Universidad de Malaga Malaga 29071 Spain

Composites of carbon aerogel and graphite oxide（GO） were synthesized using a self-assembly method based on dispersive forces. Their surface was modified by treatment in hydrogen sulfide at 650 and800 ℃. The samples obtained were characterized by adsorption of nitrogen, TA-MS, XPS, potentiometric titration, and HRTEM and tested as catalysts for oxygen reduction reactions（ORR） in an alkaline *** synergistic effect of the composite（electrical conductivity, porosity and surface chemistry） leads to a good ORR catalytic activity. The onset potential for the composite of carbon aerogel heated at 800 ℃ is shifted to a more positive value and the number of electron transfer was 2e-at the potential 0.68 V versus RHE and it increased to 4e-with an increase in the negative values of the potential. An excellent tolerance to methanol crossover was also recorded.

关键词： Oxygen reduction reaction Carbon aerogel/GO composites Porosity Surface chemistry Specific interactions

Coumarin-derived azolyl ethanols:synthesis,antimicrobial evaluation and preliminary action mechanism

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Science China Chemistry 2016年第7期59卷 878-894页

作者： Xin-Mei Peng Kannekanti Vijaya Kumar Guri l.V. Damu Cheng-He Zhou Institute of Bioorganic & Medicinal Chemistry Key Laboratory of Applied chemistry of Chongqing MunicipalitySchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China

A series of coumarin-derived azolyl ethanols including imidazolyl,triazolyl,tetrazolyl,benzotriazolyl,thiol-imidazolyl and thiol-triazolyl ones were conveniently synthesized and characterized by IR,~1H NMR,^(13)C NMR and high-resolution mass spectra(HRMS) *** of the prepared compounds showed appropriate logP_(ow) values and effective antibacterial and antifungal ***,compound 14 with bis-triazolyl ethanol group exhibited low minimal inhibitory concentration(MIC)value of 8 μg/ml against MRSA,which was comparable or even superior to reference drugs Norfloxacin(MIC=8μg/ml)and Chloramphenicol(MIC=16μg/ml).It could also effectively inhibit the growth of the tested fungal strains compared to *** binding studies of coumarin 14 with calf thymus DNA were investigated by UV-Vis absorption and fluorescence *** was found that compound 14 could interact with calf thymus DNA by groove binding to form14-DNA complex via both hydrogen bonds and van der Waals force,which might be the factor to exert the powerful antimicrobial activity.

关键词： coumarin imidazole triazole tetrazole antibacterial antifungal calf thymus DNA

The role of radiotherapy in the management of localized soft tissue sarcomas

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Cancer Biology & Medicine 2016年第3期13卷 373-383页

作者： Siaw Sze Tiong Colleen Dickie Rick l.Haas Brian O'Sullivan Department of Radiation Oncology Princess Margaret Cancer Center University of Toronto Department of Radiotherapy The Netherlands Cancer Institute Antoni van Leeuwenhoek Hospital

The combination of radiotherapy(RT) and function-preserving surgery is the most usual contemporary approach in the management of soft tissue sarcomas(STS). Pre- and postoperative RT result in similar local control rates, as shown by a landmark trial in extremity STS. In this review, the role of RT in the management of extremity STS will be discussed, but STS in other sites,including retroperitoneal STS, will also be addressed. The focus will consider various aspects of RT including strategies to reduce the volume of tissue being irradiated, dose, scheduling, and the possible of omission of RT in selected cases. Finally, technology advances through the use of intensity-modulated radiotherapy(IMRT), image-guided IMRT, intraoperative radiotherapy(IORT)and particle therapy will also be discussed.

关键词： Sarcoma radiotherapy retroperitoneal sarcoma surgery extremity sarcoma

Comparison of Velocity Shear with Turbulence Reduction Driven by Biasing in a Simple Cylindrical Slab Plasma

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Plasma Science and Technology 2010年第4期12卷 391-396页

作者： K.W.GENTlE K.lIAO K.lEE W.l.ROWAN Institute of Fusion Studies University of Texas at Austin

In an experimental realization of the sheared cylindrical slab, the level of plasma turbulence is strongly reduced by application of a sufficient bias potential difference in the radial direction. Density fluctuation levels △nrms/n decrease by more than a factor of five. The ion flow velocity profile is measured spectroscopically from the Doppler shift of an argon ion line. Comparison of the shearing rates with the turbulent amplitudes as a function of bias show no relation between the shearing rate and turbulence reduction, contrary to expectations.

关键词： turbulence suppression shear stabilization velocity shear bias

Metabolomic Fingerprinting of Blood Samples by Direct Infusion Mass Spectrometry:Application in Alzheimer’s Disease Research

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Journal of Analysis and Testing 2017年第3期1卷 83-91页

作者： Rau´l Gonza´lez-Domı´nguez Department of Chemistry Faculty of Experimental SciencesUniversity of Huelva21007 HuelvaSpain

Metabolomics is largely employed in numerous biomedical research fields,such as the study of the underlying pathology of diseases,discovery of diagnostic biomarkers,or drug ***,the main challenge is to obtain comprehensive and unbiased metabolomic profiles due to the huge complexity,heterogeneity,and dynamism of the *** this end,mass spectrometry represents a very interesting analytical platform,since the complexity of metabolome may be overcome through the use of different orthogonal separation techniques,including liquid chromatography,gas chromatography,and capillary ***,direct mass spectrometry analysis has been postulated as a complementary choice to hyphenated *** technique exhibits several advantages such as the ability for high-throughput screening,fast analysis,and wide metabolomic coverage,since there is not exclusion of compounds due to the separation *** present work explores the utility of metabolomics based on direct infusion mass spectrometry for analyzing blood *** most important analytical concerns to be considered are discussed,including sample handling,comprehensive fingerprinting,as well as subsequent identification of metabolites,and global characterization of metabolomic *** conclude,a brief review on the application of these metabolomic platforms in Alzheimer’s disease research is also provided.

关键词： Metabolomics Direct infusion mass spectrometry Alzheimer’s disease Blood

Spermine induced reversible collapse of deoxyribonucleic acid-bridged nanoparticle-based assemblies

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Nano Research 2018年第1期11卷 383-396页

作者： Kristian l. Goeken Richard B. M. Schasfoort Vinod Subramaniam Ron Gill MIRA Institute for Biomedical Technology and Technical Medicine University of Twente Dfienerlolaan 5 7522 NB Enschede the Netherlands Vrije UniversiteitAmsterdam De Boelelaan 1105 1081 HVAmsterdam the Netherlands Saxion University of Applied Sciences M. H. Tromplaan 28 7513 A8 Enschede the Netherlands

DNA-linked 2D and 3D nano-assemblies find use in a diverse set of applications, ranging from DNA-origami in drug delivery and medical imaging, to DNA-linked nanoparticle structures for use in plasmonics and （bio）sensing. However, once these structures have been fully assembled, few options are available to modulate structure geometry. Here, we investigated the use of the polycation spermine to induce DNA collapse in small oligonucleotide-linked （54 bp） gold nanoparticle structures by monitoring shifts in the localized surface plasmon resonance （lSPR） peak and by comparing the data with finite-difference time-domain （FDTD） simulations. Our data shows that low concentrations of spermine can be applied to induce large changes in DNA conformation, leading to a significant reduction in interparticle distance （from - 25 to - 3 nm） and enhanced plasmonic coupling. The DNA collapse is near-instantaneous and reversible, and its application at low and high DNA densities is demonstrated with surface plasmon resonance imaging （SPRi）, showing the potential of spermine to dynamically modulate distances and geometry in DNA-based nano-assemblies.

关键词： nanoparticles spermine deoxyribonucleic acid localized surface plasmonresonance surface plasmon resonanceimaging