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Phase transformation behaviors and mechanical properties of Ti_(50)Ni_(49)Fe_1 alloy with severe plastic deformation

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Rare Metals 2013年第5期32卷 448-452页

作者： wen Ma Bin Chen fu-shun liu Qing Xu Division of Science and Technology Information General Research Institute for Nonferrous Metals School of Material Science and Engineering Beijing University of Aeronautics and Astronautics Metrology and Phsico-Chemical Institute Capital Aerospace Machinery Company

In this work, transformation behaviors and mechanical properties of cold-rolled shape memory alloy TisoNia9Fel by severe plastic deformation （SPD） were intensively investigated. The phase transformation behaviors, phase analysis, and microstructures were characterized by differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, and transmission electron microscopy （TEM）, respectively. Tensile testing was performed to analyze the effect of SPD on the mechanical properties and shape memory of TisoNi49Fel alloy. When the thickness reduction is beyond 30 %, the martensitic transformation is suppressed. After cold-rolling, the alloy is mainly com- posed of B2 parent phases with some stress-induced martensitic B 19t phases, and high density of dislocations are generated and the grains are obviously refined. The yield stress ab significantly raises from 618 MPa of 0 % cold rolling to 1,338 MPa of 50 % SPD. Shape-memory effect increases from 6.5 % without cold rolling to 8.5 % after 30 % SPD, ascribed to the induced defects in cold rolling. Those results indicate that TisoNi49Fel alloy has improved mechanical properties and potential commercial applications after SPD.

关键词： TiNiFe alloy Cold-rolling Severe plasticdeformation (SPD) Shape memory effect

Crystallization behavior in severely cold-drawn Ti_(50) Ni_(47) Fe_3 wire

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Rare Metals 2014年第3期33卷 258-262页

作者： Xin-Quan Zhang Hui-Fang Geng fu-shun liu wen Ma The Integrated Standard and Material Application Research Department AVIC The First Aircraft Institute School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Division of Science and Technology Information General Research Institute for Nonferrous Metals

The microstructures and crystallization behavior of Ti-47 at% Ni-3 at% Fe shape memory alloy wire under the condition of severe cold drawing at room temperature and different post-deformation annealing processes were intensively investigated using transmission electron microscope（TEM） and differential scanning calorimetry（DSC）. It is indicated that the amorphous phase is dominant in the Ti50Ni47Fe3 wire after the cold drawing of 78 % areal reduction. The critical temperature for recrystalization is determined at about 300 °C. The average grain size grows from 7 up to 125 nm when annealing temperature rises from300 to 500 °C. Post-deformation annealing process exerts significant influence on the crystallization temperature which climbs up with the increase of annealing temperature.

关键词： TisoNi47Fe3 wire Cold drawing Annealing Amorphous Crystallization

ID effects on beam dynamics in the SSRF-U storage ring

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Nuclear Science and Techniques 2023年第11期34卷 140-154页

作者： Li‑Yuan Tan shun‑qiang Tian Xin‑Zhong liu Xu Wu wen‑Zhi Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

This paper introduces the proposed insertion device(ID)scheme for the Shanghai Synchrotron Radiation Facility *** on this scheme,the influences of the ID radiation on the intra-beam scattering emittance and energy spread were *** distortion caused by the IDs was comprehensively examined and compensated using both local and global ***,a frequency map analysis method was used to identify potentially dangerous resonance *** addition,the dynamic aperture,energy acceptance,and Touschek lifetime were calculated after considering high-order magnetic field errors to ensure that the ID effect did not affect the operation of the storage ring.

关键词： SSRF-U Insertion devices Emittance Beam dynamic

Transformation behaviors and superelasticity of Ti_(50)Ni_(48)Fe_2 shape memory alloy subjected to cold-rolling and subsequent annealing

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Rare Metals 2014年第6期33卷 652-656页

作者： Xiao-Bo Yuan Bin Chen fu-shun liu Qing Xu wen Ma School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Capital Aerospace Machinery Company Division of Science & Technology Information General Research Institute for Nonferrous Metals

The effects of annealing on the phase transformation behavior and superelasticity of cold-rolled Ti50Ni48Fe2 shape memory alloy were extensively investigated. Curves of temperature dependence of electrical resistivity reveal that both the cold-rolled and annealed specimens exhibit a B2→R→B19’two-stage martensitic transformation upon cooling and a B19’→B2 one-stage transformation upon heating, although the austenitic transformation temperature decreases with the increase of the annealing temperature. Tensile stress–strain curves show the critical stress for stress-induced martensite（rSIM）of Ti50Ni48Fe2 alloys decreases with the increase of annealing temperature due to the decrement of dislocation density caused by the recrystallization. As a result, the rSIM decreases. Upon a cold-rolling and annealing at 623 K for30 min, the Ti50Ni48Fe2 alloy exhibits excellent superelasticity with the maximum recoverable strain of 5.8 % at a loading strain of 7 %. In such a case, a complete superelasticity of 5 % can be obtained in the Ti50Ni48Fe2 alloy after deformation increasing to 15 cycles.

关键词： Shape memory alloys Cold-rolling Annealing Superelasticity

Synthesis and performance of Ca-α/β-SiAlON composites from tailings

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 515-522页

作者： Hong-shun Hao Yang Yang Fang Lian wen-yuan Gao Gui-shan liu Zhi-qiang Hu Institute of New Energy Materials Dalian Polytechnic University Liaoning Provincial Key Laboratory of New Materials and Material Modification Dalian Polytechnic University School of Materials Science and Engineering University of Science and Technology Beijing

Ca-α/β-SiAlON composites were prepared using Ca-α/β-SiAlON powder synthesized from gold ore tailings, which contained abundant Si and Al elements as the major raw materials together with minor additives, through a pressure-less sintering method. The influ- ences of sintering temperature on the phase composition and mierostrueture of the composites were analyzed. The scanning electron micros- copy images of the composites show the interlacing of grains with elongated columnar, short columnar and plate-like morphologies. The composites sintered at 1520℃ for 6 h have a flexural strength of 352 MPa, Vickers hardness of 11.2 GPa, and fracture toughness of 4.8 MPa·m1/2. The relative content of each phase in the products is I（Ca-α-SiAION）：I（β-SiAlON）：I（Fe3Si） = 23：74：3, where Ii stands for the dif- fraction peak intensity of phase i.

关键词： ceramic materials composite materials tailings mechanical properties microstructure sintering

Assembly-oriented reliability analysis method for the top-connection structure of a nuclear fuel assembly

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Nuclear Science and Techniques 2023年第6期34卷 155-170页

作者： Ying-Dong liu wen-qiang Li Jia-Hao Chen Si-Tong Ling Chang-fu Wan School of Mechanical Engineering Sichuan UniversityChengdu610065China Innovation Method and Creative Design Key Laboratory of Sichuan Province Chengdu610065China

The nuclear fuel assembly is the core component of a nuclear *** a pressurized water reactor fuel assembly,the top-connection structure connects the top nozzle to the guide *** performance reliability is essential for the stability of the nuclear fuel *** this study,an assembly-oriented reliability analysis method for top-connection structures is presented by establishing an assembly-oriented top-connection structure parameter modeling method and a nonlinear contact gap and penetration correction method.A reliability model of the top-connection assembly structure,including multiple stochastic design variables,was constructed,and the overall reliability of the top-connection assembly structure was obtained via a Kriging model and Monte Carlo *** acquired experimental data were consistent with real-world failure conditions,which verified the practicability and feasibility of the reliability analysis method proposed in this study.

关键词： Assembly Top-connection structure Parametric model Approximation model Structural reliability

^(18)F-Fluorodeoxyglucose positron emission tomography/computed tomography comparison of gastric lymphoma and gastric carcinoma

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World Journal of Gastroenterology 2016年第34期22卷 7787-7796页

作者： Xiao-Feng Li qiang fu You-wen Dong Jian-Jing liu Xiu-Yu Song Dong dai Cong Zuo wen-Gui Xu Department of Molecular Imaging and Nuclear Medicine Tianjin Medical University Cancer Institute and Hospital National Clinical Research Center for Cancer Key Laboratory of Cancer Prevention and Therapy

AIM To compare ^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography(^(18)F-FDG PET/CT) features in gastric lymphoma and gastric *** Patients with newly diagnosed gastric lymphoma or gastric carcinoma who underwent ^(18)F-FDG PET/CT prior to treatment were included in this study. We reviewed and analyzed the PET/CT features of gastric wall lesions,including FDG avidity,pattern(focal/diffuse),and intensity [maximal standard uptake value:(SUVmax)]. The correlation of SUVmax with gastricclinicopathological variables was investigated by χ~2 test,and receiver-operating characteristic(ROC) curve analysis was performed to determine the differential diagnostic value of SUVmax-associated parameters in gastric lymphoma and gastric carcinoma. RESULTS Fifty-two patients with gastric lymphoma and 73 with gastric carcinoma were included in this study. Abnormal gastric FDG accumulation was found in 49 patients(94.23%) with gastric lymphoma and 65 patients(89.04%) with gastric carcinoma. Gastric lymphoma patients predominantly presented with type Ⅰ and type Ⅱ lesions,whereas gastric carcinoma patients mainly had type Ⅲ lesions. The SUVmax(13.39 ± 9.24 vs 8.35 ± 5.80,P < 0.001) and SUVmax/THKmax(maximal thickness)(7.96 ± 4.02 vs 4.88 ± 3.32,P < 0.001) were both higher in patients with gastric lymphoma compared with gastric carcinoma. ROC curve analysis suggested a better performance of SUVmax/THKmax in the evaluation of gastric lesions between gastric lymphoma and gastric carcinoma in comparison with that of SUVmax *** PET/CT features differ between gastric lymphoma and carcinoma,which can improve PET/CT evaluation of gastric wall lesions and help differentiate gastric lymphoma from gastric carcinoma.

关键词： Gastric lymphomas Gastric carcinomas 18F-fluorodeoxyglucose positron emission tomography/ computed tomography Maximal standard uptake value Maximal thickness Differential diagnosis

Improving Thermal-oxidative Aging Resistance of Styrene-butadiene Rubber by Antioxidant Loaded Silica Aerogel

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Chinese Journal of Polymer Science 2024年第8期42卷 1198-1209页

作者： Xue-Fei Ping Yu Wang Lu liu fu-Yong liu Hong-Wei He Pi Wang wen-wen Yu qiang Zheng College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China Key Laboratory of Macromolecular Synthesis and functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

The antioxidant N-isopropyl-N'-phenyl-p-phenylenediamine(4010NA)was dissolved in ethanol and impregnated into silica aerogel(SAG)via vacuum-pressure cycles,yielding composite particles(A-N)with enhanced sustained-release and reinforcing *** effect of A-N on the mechanical properties and thermal-oxidative aging resistance of styrene-butadiene rubber(SBR)vulcanizates was *** and BET assessments indicated that the loading efficiency of 4010NA in SAG reached 14.26%within ethanol's solu bility *** A-N into SBR vulcanizates significantly elevated tensile strength by 17.5%and elongation at break by 41.9%over those with fumed silica and ***,A-N notably enhanced the thermal-oxidative aging resistance of *** aging for 96 h at 100℃,the tensile strength and elongation at break of SBR with A-N sustained 70.09%and 58.61%of their initial values,respectively,with the retention rate of elongation at break being 62.8%higher than that of SBR with fumed silica and free *** study revealed that A-N composite particles significantly inhibited the crosslinking in SBR's molecular chains,reducing hardening and embrittlement during later thermal-oxidative aging stages.

关键词： Styrene-butadiene rubber Silica aerogel Loading modification Thermal-oxidative aging

Identification of key genes involved in flavonoid and terpenoid biosynthesis and the pathway of triterpenoid biosynthesis in Passiflora edulis

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Journal of Integrative Agriculture 2023年第5期22卷 1412-1423页

作者： XU Yi HUANG Dong-mei MA fu-ning YANG liu WU Bin XING wen-ting SUN Pei-guang CHEN Di XU Bing-qiang SONG shun National Key Laboratory for Tropical Crop Breeding/Haikou Experimental Station Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Genetic Improvement of BananasSanya Research Institute of Chinese Academy of Tropical Agricultural SciencesSanya 572000P.R.China Hainan Yazhou Bay Seed Laboratory Sanya 572000P.R.China Guangxi Crop Genetic Improvement and Biotechnology Laboratory Guangxi Academy of Agricultural SciencesNanning 530007P.R.China

Passion fruit(Passiflora edulis Sims) is a vine of the Passiflora genus in the Passifloraceae family. The extracted components include flavonoids and terpenoids, which have good anti-anxiety and anti-inflammatory effects in *** this study, we analyzed the transcriptomes of four tissues of the ‘Zixiang’ cultivar using RNA-Seq, which provided a dataset for functional gene mining. The de novo assembly of these reads generated 96 883 unigenes, among which 61 022 unigenes were annotated(62.99% yield). In addition to its edible value, another important application of passion fruit is its medicinal value. The flavonoids and terpenoids are mainly derivatives of luteolin, apigenin, cycloartane triterpenoid saponins and other active substances in leaf extracts. A series of candidate unigenes in the transcriptome data that are potentially involved in the flavonoid and terpenoid synthesis pathways were screened using homologybased BLAST and phylogenetic analysis. The results showed that the biosynthesis of triterpenoids in passion fruit comes from the branches of the mevalonate(MVA) and 2-C-methyl-D-erythritol 4-phosphate/1-deoxy-D-xylulose 5-phosphate(MEP/DOXP) pathways, which is different from the MVA pathway that is used in other fruit trees. Most of the candidate genes were found to be highly expressed in the leaves and/or flowers. Quantitative real-time PCR(qRT-PCR) verification was carried out and confirmed the reliability of the RNA-Seq data. further amplification and functional analysis of these putative unigenes will provide additional insight into the biosynthesis of flavonoids and terpenoids in passion fruit.

关键词： passion fruit RNA-Seq gene mining flavonoids terpenoids