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Microstructural characterization and mechanical properties of(TiC+TiB)/TA15 composites prepared by an in-situ synthesis method

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China Foundry 2024年第2期21卷 168-174页

作者： Zhi-y.ng Zhang Jiao-jiao Cheng Jia-qi xie Shi-bing Liu Kun Shi Jun Zhao Sheny.ng Research Institute of Foundry Co. Ltd.CAMShenyang 110022China National Key Laboratory of Advanced Casting Technologies Shenyang 110022China

Titanium matrix composites reinforced with ceramic particles are considered a promising engineering material due to their combination of high specific strength,low density,and high *** this study,the TA15-based composites reinforced with a volume fraction of 10% to 25%(TiB+TiC)were prepared using powder metallurgy and casting *** characterization and phase constitution were examined using optical microscopy(OM),scanning electron microscopy(SEM),and X-ray diffraction(XRD).In addition,the microhardness,room temperature(RT)and high temperature(HT)tensile properties of the composites were *** revealed that the reinforcements are distributed uniformly even in the composites with a high volume of TiB and ***,as the volume fraction exceeds 15%,TiB and TiC particles become coarsening and exhibit rod-like and dendritic-like *** increases gradually from 321.2 HV for the base alloy to a maximum of 473.3 HV as the reinforcement increases to 25vol.%.Tensile test results indicate that a reinforcement volume fraction above 20% is beneficial for enhancing tensile strength and yield strength at high temperatures,but it has an adverse effect on room temperature ***,if the reinforcement volume fraction is below 20%,it can improve high-temperature elongation when the temperature exceeds 600℃.

关键词： titanium matrix composites microstucture microhardness tensile properties in-situ synthesis

Nonlinear Absorption and Dispersion Response in Optically Dense Media Driven by a Single-Mode Laser

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Communications in Theoretical Physics 2006年第1X期46卷 130-134页

作者： LI Jia-Hua LIU Ji-bing xie Xiao-Tao LUO Jin-Ming Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

Taking the density-dependent near dipole-dipole （NDD） interaction into consideration, we theoretically investigate the response of nonlinear absorption and dispersion in optically dense media of three-level atoms driven by a single-mode probe laser. The influence of the NDD effects on the absorption and dispersion spectra of the probe field is predicted via numerical calculations. It is shown that the NDD effects reduce gradually to transient absorption and amplification with the increase of the strengths of the NDD interaction, but do not change the steady-state behavior. Due to the presence of the NDD effects, steady-state absorption spectra exhibit asymmetric double-peak structure and overall shifts when a continuous-wave （cw） probe field is applied. However, frequency dispersion spectra are insensitive to them near the zero detuning.

关键词： absorption spectra dispersion spectra near dipole-dipole interactions

New Discovery and Zircon Hf Isotopic Composition of the Early yanshannian Monzogranite in the y.ngy.ngguan Group of Eastern Guangxi, China

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1653-1655页

作者： LI Xiang TU bing WAng Lingzhan TIAN y.ng xie Guogang ZHAng Jianyu Wuhan Center of Geological Survey China Geological Survey Research Center of Granitic Diagenesis and Mineralization China Geological Survey School of Earth Sciences China University of Geosciences

Objective The y.ngy.ngguan Group is widely exposed in the southwestern segment of boundary belt between y.ngtze and Cathaysian blocks and is mainly composed of a suit of lower-grade metamorphic marine volcanoclastic- sedimentary rocks （Zhou Hanwen et al., 2002）. Its forming age and petrogenesis are critical for better understanding the orogenic process and relationship of the y.ngtze and Cathaysian blocks since the Neoproterozoic. However, few zircon U-Pb ages of samples from the y.ngy.ngguan Group have been reported, which are much debated, such as the metamorphic spilite （819±11 Ma）, keratophyre （415.1±2.1 Ma） and ignimbrite （821.3±3.9 Ma）（Tian y.ng et al., 2015 and references in）. In this study, we focus on the new discovered Early yanshannian monzogranite and its mafic enclaves from the y.ngy.ngguan Group, and conducted zircon U-Pb dating and in-situ Hf isotopic analyses to constrain their petrogenesis.

关键词： Hf ICP MS Pb New Discovery and Zircon Hf Isotopic Composition of the Early yanshannian Monzogranite in the y.ngy.ngguan Group of Eastern Guangxi China

Effects of Labeling Thiophilic FRET Dyes on the Stability and Dimerization Process of β-Lactoglobulin

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Chinese Physics Letters 2011年第11期28卷 271-274页

作者： PAN Hai xie Jin-bing CAO yi QIN Meng WAng Wei National Laboratory of Solid State Microstructure and Department of Physics Nanjing UniversityNanjing 210093

The stability and dimeric state of𝛽β-lactoglobulin(β-lg)can be dramatically affected by labeling the thiophilic agent to Cys121,whereas the underlining mechanism of such an effect is still *** label a fluorescenceresonance-energy-βtransfer(FRET)pair of donor(1,5-IAEDANS)and acceptor(5-IAF)dyes to Cys121 of𝛽β-lg monomers to investigate the effect of bulky thiophilic modification on the structure and stability of𝛽β-*** is found that the modification dramatically destroys the native structure ofβ-lg and results in an obvious increase of the𝛼-helical content,coincident with the accumulation of non-native𝛼α-helical intermediates during its folding ***,the dimeric state of𝛽β-lg can still be reached whereas its dimerization rate decreases dramatically,allowing us to characterize the dimerization process using the FRET method based on a stoppedflow *** results reveal that the dimerization process occurs before the completely folding of individual monomers,providing direct evidence on the cooperativity of folding and binding processes.

关键词： process helical stability

Recent Progress in AIE-active Polymers

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Chinese Journal of Polymer Science 2019年第4期37卷 289-301,I0004页

作者： yu bing Hu Jacky W.y.Lam Ben Zhong Tang HKUST-Shenzhen Research Institute Department of Chemistry The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction and Institute for Advanced StudyThe Hong Kong University of Science and Technology Center for Aggregation-Induced Emission SCUT-HKUST Joint Research InstituteState Key Laboratory of Luminescent Materials and DevicesSouth China University of Technology

The demand for highly efficient solid-state luminophores is continuously growing due to their potential applications in optoelectrical devices, chemosensors, and biological applications. The discovery of luminogens with aggregation-induced emission(AIE)by Tang et al. in 2001 provides a good reponse to this demand. Among the exploited AIE luminogens, AIE-active polymers possess many advantages such as simple synthesis, convenient structrue modifications, and good processability, which offer an extensive platform for scientists and engineers. Herein, the design principles and latest synthetic advancement of AIE-active polymers are summarized, including click polymerization and multicomponent polymerization. Non-conjugated heteroatom-rich polymers were in situ generated and demonstated non-conventional clusteroluminoscence. Advanced applications including fluorescent sensors, stimuli-responsive materials,biological applications, circularly polarized luminescence, and electroluminescence are then introduced in detail. AIE-active polymers display the signal-amplification effect for sensitive and selective response to chemo/bioanalytes or stimuli and enhanced photosensitization effect for cancer theranostics. Retrospecting the expansion of this field can further strengthen our belief that AIE-active polymers are promising for conceptual innovation and technological breakthroughs in the near future.

关键词： Aggregation-induced emission Polymer synthesis High-tech application

Geometric Phase in a Time-Dependent A-Type Jaynes-Cummings Model

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Communications in Theoretical Physics 2009年第3期51卷 407-410页

作者： QIN Xian-Ming yU Zbao-Xian JIAO Zhi-y.ng xie bing-Hao Department of Mathematics and Physics Chongqing University of Science and Technology Chongqing 400042 China Department of Physics Beijing Information Science and Technology University Beijing 100192 China Department of Physics China University of Petroleum （East China） Dongying 257061 China

By using the Lewis-Riesenfeld invariant theory, we have studied the dynamical and the geometric phases in a generalized time-dependent A-type Jaynes Cummings model. We lind that, compared with the dynamical phases, the geometric phases in a cycle case are independent of the frequency of the photon field, the coupling coefficient between photons and atoms, and the atom transition frequency. It is pointed out that the geometric phases in a cycle ease can be measured under the case of a stronger time-dependent photon field and a stronger coupling photon-atom system. On the other hand, the geometric phases of the model may be measured in the composition of cold atoms.

关键词： geometric phase generalized Jaynes-Cummings model

Active gastrointestinal diverticulum bleeding diagnosed by computed tomography angiography

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World Journal of Gastroenterology 2014年第37期20卷 13620-13624页

作者： xie-Qun Xu Tao Hong bing-Lu Li Wei Liu Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical College

A diverticulum is a bulging sack in any portion of the gastrointestinal tract. Small intestine diverticular disease is much less common than colonic diverticular disease. The most common symptoms include non-specific epigastric pain and a bloating sensation. Major complications include diverticulitis, gastrointestinal bleeding, acute perforation, intestinal obstruction, intestinal perforation, localized abscess, malabsorption, anemia,volvulus and bacterial overgrowth. We report one case of massive jejunal diverticula bleeding and one case of massive colonic diverticula bleeding, both diagnosed by acute abdominal computed tomography angiography and treated successfully by surgery.

关键词： Diverticulum Gastrointestinal diverticular bleeding Angiography Computed tomography angiography Endoscopy

Nonlinear Absorption-Gain Response and Population Dynamics in a Laser-Driven Four-Level Dense Atomic System

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Communications in Theoretical Physics 2006年第6期45卷 1102-1106页

作者： LI Jia-Hua LIU Ji-bing LUO Jin-Ming xie Xiao-Tao Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We theoretically investigate the response of nonlinear absorption and population dynamics in optically dense media of four-level atoms driven by a single-mode probe laser, via taking the density-dependent near dipoledipole （NDD） interactions into consideration. The influence of the NDD effects on the absorption of the probe field and population dynamics is predicted via numerical calculations. It is shown that the NDD effects can reduce gradually to transient absorption with the increase of the strengths of the NDD interactions, and transient amplification can be achieved. In the steady-state limit, the probe field exhibits transparency for strong NDD interactions. Alternatively, the population entirely remains at the ground state due to the NDD effects.

关键词： absorption spectra population dynamics near dipole-dipole interactions

Microemulsion leaching of vanadium from sodium-roasted vanadium slag by fusion of leaching and extraction processes

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International Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 974-980页

作者： yun Guo Hong-yi Li yi-heng yuan Jie Huang Jiang Diao Gang Li bing xie College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

The fusion of the leaching and purification processes was realized by directly using microemulsion as the leaching *** bis-(2-ethyhexyl)phosphoric acid(DEHPA)/n-heptane/NaOH microemulsion system was established to directly leach vanadates from sodium-roasted vanadium *** effect of the leaching agent on the leaching efficiency was investigated,in addition to the molar ratio of H_(2)O/NaDEHP(W),DEHPA concentration,solid/liquid ratio,stirring time,and leaching *** optimal situations,the vanadium leaching efficiency reaches 79.57%.The X-ray diffraction characterization of the leaching residue and the Raman spectrum of the microemulsion before and after leaching demonstrate the successful entry of vanadates from the sodium-roasted vanadium slag into the *** proposed method successfully realizes the leaching and purification of vanadates in one step,thereby greatly reducing production costs and environmental *** also offers a new way to achieve the green recovery of valuable metals from solid resources.

关键词： vanadium slag sodium roasting clinker microemulsion leaching extraction