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On significance of initial microstructure in governing mechanical behavior and fracture of dual-phase steels

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Journal of Iron and Steel Research International 2018年第9期25卷 932-942页

作者： Yong-gang Deng Hong-shuang di R. D. K. Misra State Key laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China laboratory for Excellence in Advanced Steel Research University of Texas El Paso TX 79968 USA

different initial microstructures were obtained through combination of intercritical annealing and cold-rolling. Subsequently, steels with different microstructures of ferrite-pearlite （FP）, ferrite-martensite （FM） and complete martensite （M） were intercritically annealed at 780 ℃ for 5 min and water quenched to obtain ferrite-martensite microstructure. The significance of initial microstructures on ultimate microstructure, mechanical properties, strain-hardening ability and fracture behavior in dual-phase steels has been elucidated. Initial microstructures of FP, FM and M yielded different martensite morphologies, notably chain-like network structure, fine and fibrous martensite structure, respectively. Furthermore, with increasing martensite content in the initial microstructure, the average grain size of ferrite was significantly refined from about 12.3 to 2.1 μm, which results in that the ultimate tensile strength （UTS） and yield strength were increased, total elongation remained unaffected, and uniform elongation （UE） and strain-hardening ability were increased. A comparison of mechanical properties for different initial microstructures suggested that when the initial microstructure was complete martensite, the steel had excellent mechanical properties, with UTS × UE of 122.5 J cm^-3, which was 24% greater than the conventional continuously annealed steels with ferrite-pearlite initial microstructure （98.8 J cm^-3）. The variation in tensile properties, strain-hardening ability and fracture mechanism of steels with different initial microstructures were discussed in relation to the ultimate microstructures.

关键词： Dual-phase steel Microstructure Mechanical property Strain-hardening Fracture

Crystal structure of the N-terminal ankyrin repeat domain of TRPV3 reveals unique conformation of fi nger 3 loop critical for channel function

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Protein & Cell 2013年第12期4卷 942-950页

作者： di-Jing Shi Sheng Ye Xu cao Rongguang Zhang KeWei Wang Department of Neurobiology Neuroscience Research InstitutePeking University Health Science CenterBeijing 100191China National laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Department of Molecular and Cellular Pharmacology State Key Laboratory of Natural and Biomimetic DrugsPeking University School of Pharmaceutical SciencesBeijing 100191China PKU-IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China

In all six members of TRPV channel subfamily,there is an ankyrin repeat domain(ARD)in their intracellular ***(ANK)repeat,a common motif with typi-cally 33 residues in each repeat,is primarily involved in protein-protein *** the sequence similarity among the ARDs of TRPV channels,the struc-ture of TRPV3-ARD,however,remains ***,we report the crystal structure of TRPV3-ARD solved at 1.95Åresolution,which reveals six-ankyrin *** overall structure of TRPV3-ARD is similar to ARDs from other members of TRPV subfamily;it,however,features a noticeable fi nger 3 loop that bends over and is stabilized by a network of hydrogen bonds and hydrophobic pack-ing,instead of being fl exible as seen in known TRPV-ARD *** recordings demonstrated that mutating key residues R225,R226,Q255,and F249 of fi nger 3 loop altered the channel activities and *** all together,our findings show that TRPV3-ARD with characteristic fi nger 3 loop likely plays an im-portant role in channel function and pharmacology.

关键词： TRPV3 ARD keratinocyte 2-APB skin

The interstellar medium:the key component in galactic evolution and modern cosmology

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Research in Astronomy and Astrophysics 2019年第2期19卷 5-14页

作者： carl Heiles di Li Naomi McClure-Griffiths Lei Qian Shu Liu Department of Astronomy University of CaliforniaBerkeley National Astronomical Observatories Chinese Academy of Sciences Key laboratory of FAST National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences Research School for Astronomy & Astrophysics Australian National University

The gases of the interstellar medium(ISM) possess orders of magnitude more mass than those of all the stars combined and are thus the prime component of the baryonic Universe. With L-band surface sensitivity even better than the planned phase one of the Square Kilometre Array(SKA1), the Five-hundredmeter Aperture Spherical radio Telescope(FAST) promises unprecedented insights into two of the primary components of ISM, namely, atomic hydrogen(HI) and the hydroxyl molecule(OH). Here, we discuss the evolving landscape of our understanding of ISM, particularly, its complex phases, the magnetic fields within, the so-called dark molecular gas(DMG), high velocity clouds and the connection between local and distant ISM. We lay out, in broad strokes, several expected FAST projects, including an all northern-sky high-resolution HI survey(22 000 deg2, 3′FWHM beam, 0.2 km s^(-1)), targeted OH mapping, searching for absorption and maser signals, etc. Currently under commissioning, the commensal observing mode of FAST will be capable of simultaneously obtaining HI and pulsar data streams, making large-scale surveys in both science areas more efficient.

关键词： ISM:atoms ISM:individual(hydrogen) ISM:molecules ISM:evolution surveys

Applications of k-covers

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1151-1160页

作者： G.di MAIO Ljubisa D.R.KOCINAC Enrico MECcaRIELLO dipartimentodi Matematica Seconda Università di NapoliVia Vivaldi 4381100 CasertaItalia Faculty of Sciences and Mathematics University of NisVisegradska 3318000 NisSerbia Facoltàdi Ingegneria Università del SannioPalazzo B.LucarelliPiazza Roma82100 BeneventoItalia

We investigate a role of k-covers in selection principles theory. Some results about relationships between Ramsey theory and game theory and selection principles that involve k-covers are also given.

关键词： selection principles,ω-cover γ-cover k-cover Hurewicz property k-groupability k-weak groupability game theory

Recovery Planning and Management Control System in Company Crisis

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Journal of Modern Accounting and Auditing 2012年第9期8卷 1326-1337页

作者： elisa Giacosa Alberto Mazzoleni University of Turin Turin Italy University of Brescia Brescia Italy

The main goal of this paper is to analyze situations of financial crisis in Italian companies. The analysis has also been focused on the company＇s attitude to overcome the financial crisis. Secondly, the authors have analyzed if the recovery project has required the introduction of a new management control system or changes to the existing management control system. The methodology is composed of several steps. First of all, the authors have analyzed the existing literature. Secondly, the authors have referred to a sample of 98 Italian recovery projects formalized by Italian private companies. The analysis of the literature and the recovery projects permits to achieve some provisional results, which have been tested through surveys. The methodology approach is inspired by the grounded theory. The findings have been several：（1） The crisis is a usual event in the lifecycle of a firm, due to a deterioration of its strength and a change of the context; （2） The timing factor has played a fundamental role in managing the crisis situation, because a late identification of the symptoms or a minimization of them can generate an irreversible situation; and （3） In addition, a recovery project includes the introduction of a new management control system or changes to the existing management control system. These new or modified management control systems use ＂feed-forward＂ mechanisms, which make early predictions about the changes in the characteristics of the competitive framework.

关键词： company crisis recovery process recovery planning management control system Italian context

Interaction of Hydrogen and Retained Austenite in Bainite/Martensite Dual-Phase High Strength Steel

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Journal of Iron and Steel Research International 2004年第1期11卷 42-46页

作者： GUJia-lin CHANGKai-di FANGHong-sheng YANGZhi-gang BAIBing-zhe TsinghuaUniversity Beijing100084China ShougangResearchInstituteofTechnology Beijing100041China

The hydrogen trapping phenomena in two bainite/martensite dual-phase high strength steels(U20Si and U20DSi)were investigated by electrochemical permeation *** hydrogen diffusivity was calculated from data of permeation delay time,and the diffusion coefficient in U20 Si is far less than that in U20 ***,the hydrogen diffusivity decreases as the volume percent of retained austenite *** experiment results show that there are different hydrogen trappings and different volume percents of retained austenite in U20 Si and U20 *** retained austenite is precipitated as *** trap binding energy for the retained austenite and hydrogen is calculated to be 40.4kJ·mol-1.

关键词： bainite martensite dual-phase high strength steel electrochemical permeation technique diffusion coefficient retained austenite trap binding energy

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钛植入物表面抗菌涂层的研究进展

生物医学工程学杂志 2024年第1期41卷 191-198页

作者：贺旭宏郭柴琼刘轩妤王玉辉梁紫微连小洁胡银春黄棣(综述) 魏延(审校) 太原理工大学生物医学工程学院生物医学工程系纳米生物材料与再生医学研究中心太原030024 太原理工大学生物医学工程研究所太原030024

近年来,钛及钛合金等骨植入材料以其卓越的机械性能和良好的生物相容性广泛应用于生物医学领域。然而在临床实践中,细菌在材料表面的黏附以及术后感染问题可能导致植入失败。根据抗菌机制,本文从抗细菌黏附、接触杀菌和光控杀菌等方面... 详细信息

近年来,钛及钛合金等骨植入材料以其卓越的机械性能和良好的生物相容性广泛应用于生物医学领域。然而在临床实践中,细菌在材料表面的黏附以及术后感染问题可能导致植入失败。根据抗菌机制,本文从抗细菌黏附、接触杀菌和光控杀菌等方面详细阐述了钛植入物的抗菌表面设计。通过采用不同技术对钛或基于钛的合金植入物进行表面修饰,抑制细菌黏附并促进骨整合,将扩大多功能钛基植入物在骨科领域的应用范围。

关键词：钛植入物生物相容性抗菌能力金属离子抗菌

Several Rules for Treating Phenol Wastewater via Oxidation by O_3/UV-formed Radicals

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Chemical Research in Chinese Universities 2006年第1期22卷 25-28页

作者： LIU Miao JIAO Xin-qian WU di diAO Wei-li ZHANG Yu College of Environment and Resources Jilin University Changchun 130012 P. R China

The treatment of phenol wastewater with an ultraviolet source and an oxone generator by introducing salicylic acid as the capturer is described. The presence of HO during the phenol degradation has been proved. The impacts of factors such as acidity and reaction time on the HO formation are also discussed. The results demonstrate that HO ＇ generated from ozone/UV oxidation under a basic condition is the immediate cause of phenol degradation. At room temperature and a pH value of 9. 93, the degradation of phenol occurs rapidly within 0. 5 rain and the removal of phe- nol（ 100 mg/L） is above 98. 5% within 15 min; in the meantime, the pH value declines gradually with the degradation of phenol. A discussion about the formation and the transformation of the intermediate products during phenol degradation is included.

关键词： Ozone UV oxidation Radical Phenol wastewater Degradation

Rhizobacteria helps to explain the enhanced efficiency of phytoextraction strengthened by Streptomyces pactum

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Journal of Environmental Sciences 2023年第3期125卷 73-81页

作者： Linlin Wang NinaWang di Guo Zhengzheng Shang Yiying Zhang Song Liu Yuheng Wang School of Ecology and Environment Northwestern Polytechnical UniversityXi’an 710129China Xi’an Aisen Environmental Information Technology Service Co. LtdXi’an 710119China Department of Microbiology and Immunology University of Western OntarioLondonON N6A 5C1Canada State Key laboratory of Crop Stress Biology for Arid Areas and College of Agronomy Northwest A&F UniversityYangling 712100China

The ultimate purpose of phytoextraction is not only to remove heavy metals from soil but also to improve soil ***, we evaluated how the joint effect of Streptomyces pactum(strain Act12) and inorganic(Hoagland’s solution) and organic(humic acid and peat) nutrients affected the phytoextraction practice of cadmium(Cd) and zinc(Zn) by potherb mustard, and the microbial community composition within rhizosphere was also *** results indicated that the nutrients exerted synergistically with Act12, all increasing the plant biomass and Cd/Zn *** inoculation of Act12 alone significantly increased dehydrogenase activity of rhizosphere soil(Pdifferent dosage of *** application of microbial strain with nutrients increased enzymatic activities with the elevated dosage of Act12.16S ribosomal RNA high-throughput sequencing analysis revealed that Act12 inoculation reduced the diversity of rhizosphere *** Act12 and nutrients did not change dominant phyla i.e.,Proteobacteria, Bacteroidetes, Gemmatimonadetes, Actinobacteria and Acidobacteria, but their relative abundance differed among the treatments with: Peat>Act12>Humic acid >Hoagland’s ***, Sphingomonas replaced Thiobacillus as dominant genus after Act12 *** increase in the Sphingomonas and Flavisolibacter abundances under Act12 and nutrients treatments gave rise to growth-promoting effect on *** results revealed the important role for rhizosphere microbiota in mediating soil biochemical traits and plant growth, and our approach charted a path toward the development of Act12 combined with soil nutrients to enhance soil quality and phytoextraction efficiency in Cd/Zn-contaminated soils.

关键词： Phytoextraction Streptomyces pactum Enzymatic activity Microbial community