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Synthesis of Single-Crystal TiO_2 Nanowire Using Titanium Monoxide Powder by Thermal Evaporation

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Journal of Materials Science & Technology 2012年第5期28卷 385-390页

作者： Z.G.Shang Z.Q.Liu P.J.Shang J.k.Shang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

TiO 2 nanowires were synthesized successfully in a large quantity by thermal evaporation using titanium monoxide powder as precursor. X-ray diffraction results showed that all the products were pure rutile phase of TiO 2 . According to microstructural observations, the nanowires have two typical morphologies, a long straight type and a short tortuous type. The straight nanowires were obtained at a wide temperature range of 900–1050 ℃, while the tortuous ones were formed below 900 ℃. Transmission electron microscopy characterization revealed that both the straight and the tortuous nanowires are single-crystal rutile TiO 2 . The preferential growth direction of the nanowires was determined as [110] orientation according to electron diffraction and high-resolution image analyses. The morphological change of TiO 2 nanowires was discussed by considering the different atomic diffusion rates of Ti atoms caused by the phase transformation in Ti substrate at around 900 ℃.

关键词： Rutile-TiO 2 Alloy nanowires Transmission electron microscopy (TEM) characterization Crystal structure identification Growth mechanism Thermal evaporation

Marble epistyles under shear: an experimental study of the role of “Relieving Space”

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Frontiers of Structural and Civil Engineering 2019年第4期13卷 767-786页

作者： E. D. PASIOU I. STAVRAkAS D. TRIANTIS S. k. kOURkOULIS Department of Mechanics Laboratory of Testing and Materials National Technical University of Athens Athens 15773 Greece Department of Electronics Laboratory of Electrical Characterization of Materials and Electronic Devices Technological Edu-cational Institution of Athens Athens 12210 Greece

The mechanical response of mutually interconnected epistyles is studied experimentally. The specimens are made of two marble blocks connected to each other with an “I”-shaped titanium connector placed in grooves sculptured on the blocks and covered with cementitious material. The specific way of connecting epistyles simulates the one used by scientists restoring the ancient “connections” of the epistyles of the Parthenon Temple. This “connection”, although designed to sustain mainly tensile loading, undertakes, also, shear load, in case of excitations imposing to the epistyles displacements normal to the connector’s axis. Attention is focused to enlighten the role of a novel design technique aiming to relieve the stress field around the connector. According to this technique, part of the connector’s web is left uncovered, forming the so-called “Relieving Space”, assisting the unconstrained deformation of the connector. Both traditional and innovative sensing techniques were employed in an effort to obtain data from the interior of the three-material-complex (marble-cementitious material-titanium). Analysis of the data indicated that the “Relieving Space” reduces the overall stiffness of the system, protecting marble in case of over-loading. Moreover, it was concluded that the innovative techniques employed provide pre-failure indicators well in advance of the catastrophic failure of the specimens.

关键词： monuments of cultural heritage marble epistyles pressure stimulated currents acoustic emission digital image correlation

Detonation Propagation in Narrow Gaps with Various Configurations

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Journal of Thermal Science 2007年第3期16卷 283-288页

作者： M.Monwar ynu.ac.jp) Y.Yamamoto k.Ishii T.Tsuboi Department of Mechanical Engineering Yokohama National University79-5 TokiwadaiHodogaya-kuYokohama 240-8501Japan.(Email address:d05sb192

In general all detonation waves have cellular structure formed by the trajectory of the triple points. This paper aims to investigate experimentally the propagation of detonation in narrow gaps for hydrogen-oxygen-argon mixtures in terms of various gap heights and gap widths. The gap of total length 1500 mm was constructed by three pair of stainless plates, each of them was 500 mm in length, which were inserted in a detonation tube. The gap heights were varied from 1.2 mm to 3.0 mm while the gap widths were varied from 10 mm to 40 mm. Various argon dilution rates were tested in the present experiments to change the size of cellular structure. Attempts have been made by means of reaction front velocity, shock front velocity, and smoked foil to record variations of cellular structure inside the gaps. A combination probe composed of a pressure and an ion probe detected the arrival of the shock and the reaction front individually at one measurement point. Experimental results show that the number of the triple points contained in detonation front decreases with decrease in the gap heights and gap widths, which lead to larger cellular structures. For mixtures with low detonability, cell size is affected by a certain gap width although conversely cell size is almost independent of gap width. From the present result it was found that detonation propagation inside the gaps is strongly governed by the gap height and effects of gap width is dependent on detonability of mixtures.

关键词： Detonation cellular structure gap configuration triple point

一些含杂环配体的过渡金属配合物的微波合成、光谱、热化学性质和生物活性

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无机化学学报 2012年第8期28卷 1687-1699页

作者： Jain Rajendra k Mishra A P Department of Chemistry Synthetic Inorganic&Coordination Chemistry LaboratoriesDr.H.S.Gour Central UniversitySagarMadhya Pradesh 470003India

用5-氯邻羟苯甲醛与2-氨基-5-硝基噻唑(L1H)和4-氯苯甲醛与2-氨基-3-羟基吡啶(L2H)的反应,再用传统和微波方法将生成物与Cr髥,Co(II),Ni髤和Cu髤合成了一些席夫碱配合物。用元素分析,FTIR,快原子轰击质谱,摩尔电导率,电子光谱,1H-NMR,E... 详细信息

用5-氯邻羟苯甲醛与2-氨基-5-硝基噻唑(L1H)和4-氯苯甲醛与2-氨基-3-羟基吡啶(L2H)的反应,再用传统和微波方法将生成物与Cr髥,Co(II),Ni髤和Cu髤合成了一些席夫碱配合物。用元素分析,FTIR,快原子轰击质谱,摩尔电导率,电子光谱,1H-NMR,ESR,磁化率,热分析,电导率和XRD等对这些化合物进行了表征。这些配合物在空气中稳定并有颜色。分析数据表明所有配合物金属与配体的比均为1∶2,配位数为4或6。原子轰击质谱和热分析数据说明了这些配合物的降解方式。XRD图给出了这些配合物的结晶情况。席夫碱的上述金属配合物对革兰氏阳性菌:金黄色葡萄球菌和革兰氏阴性菌:大肠埃希菌(大肠杆菌)和真菌:黑曲霉和白色念珠菌显示出良好的抗菌活性。

关键词：微波方法 O,N供体热分析生物活性

Recent progress in fatigue behavior of Mg alloys in air and aqueous media: A review

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Journal of Materials Science & Technology 2017年第10期33卷 1075-1086页

作者： B.J.Wang S.D.Wang D.k.Xu E.H.Han School of Environmental and Chemical Engineering Shenyang Ligong University CAS key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences

Due to the interactions between mechanics and chemistry, Mg alloys are inevitably subjected to the combined effect of corrosion attack and cyclic loading, which eventually leads to corrosion fatigue failure. In this paper, fundamental aspects regarding the fatigue behavior of Mg alloys have been reviewed,including：（1） fatigue behavior of Mg alloys in air and aqueous media; and（2） the influence of microstructure, anodic dissolution, hydrogen embrittlement（HE）, heat treatment and surface protection on fatigue behavior of Mg alloys. Moreover, some remaining unresolved issues and future targets to deeply understand the failure mechanism of corrosion fatigue have been described.

关键词： Magnesium alloys Fatigue Corrosion fatigue Crack initiation Hydrogen embrittlement

SERS detection of arsenic in water:A review

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Journal of Environmental Sciences 2015年第10期27卷 152-162页

作者： Jumin Hao Mei-Juan Han Songman Han Xiaoguang Meng Tsan-Liang Su Qingwu k.Wang Center for Environmental Systems Stevens Institute of Technology Agiltron Inc. 15 Presidential WayWoburnMA 01801USA Department of Chemical Engineering Renai College of Tianjin University

Arsenic（As） is one of the most toxic contaminants found in the environment. Development of novel detection methods for As species in water with the potential for field use has been an urgent need in recent years. In past decades, surface-enhanced Raman scattering（SERS）has gained a reputation as one of the most sensitive spectroscopic methods for chemical and biomolecular sensing. The SERS technique has emerged as an extremely promising solution for in-situ detection of arsenic species in the field, particularly when coupled with portable/handheld Raman spectrometers. In this article, the recent advances in SERS analysis of arsenic species in water media are reviewed, and the potential of this technique for fast screening and field testing of arsenic-contaminated environmental water samples is discussed. The problems that remain in the field are also discussed and an outlook for the future is featured at the end of the article.

关键词： Arsenic SERS Detection Speciation Nanoparticles Nanofilms

Spectroscopic properties of Er3+/Ho3+/Tm3+ doped α-SiAlON ceramics under 793 nm excitation

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Progress in Natural Science:Materials International 2021年第6期31卷 891-897页

作者： Bina Chaudhary Dhani Ram Dhakal Tae-Ho kim Soo Wohn Lee Yuwaraj k.kshetri Department of Fusion Science and Technology Sun Moon University Research Center for Eco-Multifunctional Nano Materials Sun Moon University Department of Environment and Bio-Chemical Engineering Sun Moon University

This paper reports the first demonstration of super broadband infrared downshifting emission extending from1640 nm to 2200 nm with the full width at half maximum of ～ 417 nm in lanthanides(Er3+, Ho3+, and Tm3+)-doped α-SiAlON ceramics upon 793 nm excitation. Using α-Si3N4ceramic as a precursor the lanthanides-dopedα-SiAlON ceramics were synthesized by the hot-press method. The lanthanides induced no significant secondary phases in the sintered α-SiAlON ceramics. Strong two-photon upconversion emission bands centered at 547,671 and 694 nm have also been observed upon 793 nm excitation. The time-resolved measurements of the upconversion emissions confirm that the efficient energy transfer among the Er3+, Ho3+and Tm3+ions as well as the ground state absorption in Er3+and Tm3+are responsible for the observed spectroscopic properties.

关键词： α-SiAlON Upconversion Downshifting 793 nm excitation

User-friendly finite element design of main entries, barrier pillars,and bleeder entries

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International Journal of Mining Science and Technology 2018年第1期28卷 3-10页

作者： William G.Pariseau Mark k.Larson Heather E.Lawson Douglas R.Tesarik Department of Mining Engineering University of Utah Spokane Mining Research Division NIOSH

This contribution describes development and application of a user-friendly finite element program,UT3PC, to address three important problems in underground coal mine design:(1) safety of main entries,(2) barrier pillar size needed for entry protection, and(3) safety of bleeder entries during the advance of an adjacent longwall *** the finite element method is by far the most popular engineering design tool of the digital age, widespread use by the mining community has been impeded by the relatively high cost of and the need for lengthy specialized training in numerical *** of UT3PC overcomes these impediments in three easy ***, a material properties file is prepared for the considered ***, mesh generation is automatic through an interactive process.A third and last step is simply execution of the *** using data from several western coal mines illustrate the ease of using the application for analysis of main entries, barrier pillars, and bleeder entry safety.

关键词： Finite element Coal Mine layout design Main entries Barrier pillars Bleeder entries

Formation of RRR-a-tocopherol in rumen and intestinal digestibility of tocopherols in dairy cows

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Animal Nutrition 2023年第4期15卷 350-363页

作者： Saman Lashkari Farhad M.Panah Martin R.Weisbjerg Søren k.Jensen Department of Animal and Veterinary Sciences Aarhus UniversityDenmark

Tocopherol sources in diets are often a combination of all-rac-a-tocopheryl acetate(synthetic a-tocopherol)from vitamin supplements and natural tocopherols and 2R-(4’R,8’R)-5,7,8-trimethyltocotrienol(a-tocotrienols)from the feed *** a-tocopherol consists of 8 different stereoisomers including 2R-(4’R,8’R)-5,7,8-trimethyltocol(RRR-a-tocopherol),2R-(4’S,8’R)-5,7,8-trimethyltocol(RSR-a-tocopherol),2R-(4’R,8’S)-5,7,8-trimethyltocol(RRS-a-tocopherol),2R-(4’S,8’S)-5,7,8-trimethyltocol(RSS-a-tocopherol),2S-(4’S,8’S)-5,7,8-trimethyltocol(SSS-a-tocopherol),2S-(4’R,8’S)-5,7,8-trimethyltocol(SRS-a-tocopherol),2S-(4’S,8’R)-5,7,8-trimethyltocol(SSR-a-tocopherol),and2S-(4’R,8’R)-5,7,8-trimethyltocol(SRR-a-tocopherol).The pre-absorption metabolism of tocopherols and tocotrienols in ruminants differs from monogastric animals due to the extensive microbial fermentation in the anaerobic *** current study investigated the impact of toasting and decortication of oats on metabolism in the digestive tract(synthesis,digestion),and intestinal digestibility of tocopherols in dairy cows by using 4 ruminal and intestinal cannulated Danish Holstein cows in a 4×4 Latin square design for 4 *** were fed a total mixed ration ad libitum containing different forms of oats:whole oat,decorticated oat,toasted oat,and decorticated toasted oat,all rolled before mixed *** means across 4 treatments were statistically analyzed,testing whether overall means were different from *** or toasting did not affect the balance or digestibility of a-tocopherols in *** across treatments showed the ruminal degradation of synthetic a-tocopherol(279 mg/d,P=0.02;P-value shows that average across treatments is different from zero),synthetic 2R-a-tocopherol(133 mg/d,P<0.01;summation of RRS-,RSR-and RSS-a-tocopherol),and 2S-a-tocopherol(190 mg/d;P<0.01,summation of SSS-,SRS-,SSR,and SRR-a-tocopherol),while RRR-a-tocopherol was formed in the rumen(221 mg/d,P=0.1

关键词： Vitamin E a-Tocopherol stereoisomers Toasting Decortication Cow