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Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： yi-Lang qin Ping Zhu Chen-Xi Ouyang Xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties

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Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

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Journal of Iron and Steel Research International 2024年第3期31卷 670-687页

作者： Xian-lei Hu qin-cheng Xie yi Yuan ying Zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina School of Material Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential ***,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube *** method involves a combination of cold rolling,annealing at a temperature of 550℃,and double *** morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic *** interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface *** results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al *** obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

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Nanoindentation responses of NiCoFe medium-entropy alloys from cryogenic to elevated temperatures

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Journal of Iron and Steel Research International 2024年第8期31卷 2068-2077页

作者： qin-qin Xu Kamran Karimi Amirhossein H.Naghdi Wen-yi Huo Chong Wei Stefanos Papanikolaou NOMATEN Centre of Excellence National Centre for Nuclear ResearchOtwock 05-400MazowszePoland College of Mechanical and Electrical Engineering Nanjing Forestry UniversityNanjing 210037JiangsuChina Science and Technology on Thermo Structural Composite Materials Laboratory Northwestern Polytechnical UniversityXi'an 710072ShaanxiChina School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072ShaanxiChina

NiCoFe alloy,a medium-entropy alloy,shows potential for applications in extreme ***,there is a theoretical barrier concerning the unclear understanding of its high-temperature dislocation motion *** load response exhibits distinct signatures relevant to thermal activation,most notably a decrease in critical force(i.e,softening)from cryogenic to elevated temperatures,e.g.,from 200 to 1000 *** onset of plasticity is characterized by the nucleation of stacking faults and prismatic loops at low temperatures,whereas the surface nucleation of Shockley partial dislocations dominates plasticity at elevated *** show that thermal effects lead to non-uniform atom pile-ups and control the rate of phase transformation with increasing indentation *** findings in this work extend the understanding of the mechanical response of NiCoFe alloys under indentation at different temperatures,shedding light on the underlying dislocation motion mechanisms and surface deformation *** observed transformation-induced plasticity mechanism has implications for the properties of medium-entropy alloys and their potential applications in extreme environments.

关键词： Orientation Dislocations Mechanical behaviors Phase transition

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Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation

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Nuclear Science and Techniques 2024年第5期35卷 99-108页

作者： You-Ming Deng Yong-Bin Leng Xing-yi Xu jian Chen yi-Mei Zhou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of the Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle *** is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter ***,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this *** with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed *** basic principles of the method,simulation,and experimental comparison are also *** on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal *** results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed.

关键词： Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF

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A review of inorganic particles synthesized through electrical discharge in different dielectric media: from devices, structures and components to applications

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Frontiers of Materials Science 2024年第2期18卷 1-35页

作者： yifan Liu Guilu qin Liangjun yin Xian jian Xianglong Li School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

Size effects and compositions constitute new properties for inorganic particles in different application *** physical method has recently attracted more attention in the preparation of inorganic ***,a low-cost,eco-friendly,simple-operating,and time-saving technique,named electrical discharge,is reviewed in relation to developments from the nature of this technique in different dielectric media to the practical experience in controlling the main processing parameters,apparatuses,types of discharge,from the various structures and components to the wide *** development of the electrical discharge technique will play an important role in improving the technology to prepare superfine inorganic particles with high ***,electrical discharge contributes to easily mixing solid materials from the atomic scale to several micrometers with different ***,metal oxides or doping materials are accessible as the dielectric medium is *** some excellent advantages,new inorganic particles exploited through the electrical discharge method will promise to be the most rewarding in some potential applications.

关键词： electrical discharge gas/liquid-phase dielectric medium inorganic particle sizeandcomposition application

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Exploring changes of precipitation extremes under climate change through global variable-resolution modeling

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Science Bulletin 2024年第2期69卷 237-247页

作者： Wei Sun jian Li Rucong Yu Nina Li yi Zhang State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China Department of Atmospheric Science Yunnan UniversityKunming 650091China National Meteorological Center China Meteorological AdministrationBeijing 100081China 2035 Future Laboratory PIESAT Information Technology Co.Ltd.Beijing 100105China

Understanding the responses of precipitation extremes to global climate change remains limited owing to their poor representations in models and complicated interactions with multi-scale *** we take the record-breaking precipitation over China in 2021 as an example,and study its changes under three different climate scenarios through a developed pseudo-global-warming(PGW)experimental framework with 60-3 km variable-resolution global ensemble *** to the present climate,the precipitation extreme under a warmer(cooler)climate increased(decreased)in intensity,coverage,and total amount at a range of 24.3%-37.8%(18.7%-56.1%).With the help of the proposed PGW experimental framework,we further reveal the impacts of the multi-scale system interactions in climate change on the precipitation *** the warmer climate,large-scale water vapor transport converged from double typhoons and the subtropical high marched into central China,enhancing the convective energy and instability on the leading edge of the transport *** a result,the mesoscale convective system(Mcs)that directly contributed to the precipitation extreme became stronger than that in the present *** the contrary,the cooler climate displayed opposite changing characteristics relative to the warmer climate,ranging from the large-scale systems to local environments and to the *** summary,our study provides a promising approach to scientifically assess the response of precipitation extremes to climate change,making it feasible to perform ensemble simulations while investigating the multi-scale system interactions over the globe.

关键词： Precipitation extreme Climate change Pseudo-global-warming experiment Variable-resolution modeling Multi-scale system interaction

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Microplastics may reduce the fish bioaccumulation of organic pollutants

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Science China Technological Sciences 2024年第10期67卷 3079-3090页

作者： YANG Bing ZHOU Xian HU XiaoJie qin Chao WANG jian GAO YanZheng Institute of Organic Contaminant Control and Soil Remediation College of Resource and Environmental SciencesNanjing Agricultural University

Microplastics have frequently been regarded as a threat to aquatic organisms due to their potential to enhance the accessibility of organic pollutants. However, studies of microplastics as “carriers” in the process of bioaccumulation have only been conducted on a few organic contaminants. In this study, we employed machine learning algorithms to predict the sorption capacity of 83 exogenous organic pollutants(in CCL4) on microplastics, the prediction model exhibits exceptional predictive performance,achieving R2values of 0.8651 and 0.6962, RMSE values of 0.4625 and 0.1841 for the sorption coefficients Kfand n, respectively,and quantitatively estimated the contribution of microplastics to the bioaccumulation levels of organic pollutants in Gadus morhua. By considering both natural and microplastic-ingesting pathways, we demonstrated that the ingestion of microplastics containing organic pollutants facilitates the entry of organic pollutants into Gadus morhua. However, due to their robust sorption capacity, microplastics transport the organic pollutants accumulated through the natural pathway out of the fish, thereby preventing bioaccumulation. These findings elucidate the “cleaning” mechanism of microplastics concerning various organic pollutants in aquatic organisms, providing valuable insights for accurately assessing the risk of microplastics in aquatic environments.

关键词： microplastics aquatic organisms organic pollutants machine learning risks

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Reaction mechanism between Al_(2)O_(3)–MgO refractory materials and rare earth high-carbon heavy rail steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1153-1163页

作者： yi Wang Guang-jie Song Ping Shen jian-zhong He Da-xian Zhang jian-xun Fu Center for Advanced Solidification Technology(CAST) School of Materials Science and EngineeringState Key Laboratory of Advanced Special SteelShanghai UniversityShanghai200444China State Key Laboratory of Baiyunebo Rare Earth Resources Research and Comprehensive Utilization Baotou014030Inner MongoliaChina Inner Mongolia Baotou Steel Union Co. Ltd.Baotou014030Inner MongoliaChina

Submerged entry nozzle(SEN)clogging is a major problem affecting the production quality of rare earth steel,and finding a suitable refractory outlet can significantly reduce production *** explore the relationship between refractory composition and interface interaction,unprotected coated Al_(2)O_(3)–MgO refractories and SiO2-coated Al_(2)O_(3)–MgO refractories were added to rare earth high-carbon heavy rail steel under laboratory conditions,and the Al_(2)O_(3)–MgO refractory was found to be more *** results show that,from the epoxy resin side to the refractory side,the contour of the refractory interface reaction layer can be divided into two main layers:an iron-rich reaction layer and an iron-poor reaction *** based on the spherical model suggest that the adhesion force is proportional to the size of the refractory particles and inclusions,and the same result applies to the surface *** the inclusions at a smaller size has a specific effect on alleviating the erosion of *** with the erosion mechanism of Al_(2)O_(3)–MgO refractories,the interface reaction mechanism between Al_(2)O_(3)–MgO refractories and molten steel was proposed,which provides ideas for solving SEN clogging.

关键词： Rare earth high-carbon heavy rail steel Al_(2)O_(3)-MgO refractory Adhesion Surface tension Interface interaction

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Biomimetic soft robotic wrist with 3-DOF motion and stiffness tunability based on ring-reinforced pneumatic actuators and a particle jamming joint

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Science China(Technological Sciences) 2024年第3期67卷 774-790页

作者： HU TeTe LU Xinjiang yi jian WANG YuHui XU Du State Key Laboratory of Precision Manufacturing for Extreme Service Performance School of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China

The human wrist, a complex articulation of skeletal muscles and two-carpal rows, substantially contributes to improvements in maneuverability by agilely performing three-degree-of-freedom(3-DOF) orienting tasks and regulating stiffness according to variations in interaction forces. However, few soft robotic wrists simultaneously demonstrate dexterous 3-DOF motion and variable stiffness;in addition, they do not fully consider a soft-rigid hybrid structure of integrated muscles and two carpal *** this study, we developed a soft-rigid hybrid structure to design a biomimetic soft robotic wrist(BSRW) that is capable of rotating in the x and y directions, twisting around the z-axis, and possessing stiffness-tunable capacity. To actuate the BSRW, a lightweight soft-ring-reinforced bellows-type pneumatic actuator(SRBPA) with large axial, linear deformation(η_(lcmax)=70.6%,η_(lemax)=54.3%) and small radial expansion(η_(demax)=3.7%) is designed to mimic the motion of skeletal muscles. To represent the function of two-carpal rows, a compact particle-jamming joint(PJJ) that combines particles with a membrane-covered ballsocket mechanism is developed to achieve various 3-DOF motions and high axial load-carrying capacity(>60 N). By varying the jamming pressure, the stiffness of the PJJ can be adjusted. Finally, a centrally positioned PJJ and six independently actuated SRBPAs, which are in an inclined and antagonistic arrangement, are sandwiched between two rigid plates to form a flexible,stable, and compact BSRW. Such a structure enables the BSRW to have a dexterous 3-DOF motion, high load-carrying ability,and stiffness tunability. Experimental analysis verify 3-DOF motion of BSRW, producing force of 29.6 N and 36 N and torque of2.2 Nm in corresponding rotations. Moreover, the range of rotational angle and stiffness-tuning properties of BSRW are studied by applying jamming pressure to the PJJ. Finally, a system combining a BSRW and a soft enclosing gripper is proposed to demo

关键词： pneumatic soft actuators particle jamming robotic wrist soft robotics stiffness-tunable

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Quality of life after pancreatic surgery

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World Journal of Gastroenterology 2024年第8期30卷 943-955页

作者： Shi-Zhen Li Ting-Ting Zhen yi Wu Min Wang Ting-Ting qin Hang Zhang Ren-yi qin Department of Biliary-Pancreatic Surgery Affiliated Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

BACKGROUND Pancreatic surgery is challenging owing to the anatomical characteristics of the *** attention has been paid to changes in quality of life(QOL)after pancreatic *** To summarize and analyze current research results on QOL after pancreatic *** A systematic search of the literature available on PubMed and EMBASE was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** studies were identified by screening the references of retrieved *** on patients’QOL after pancreatic surgery published after January 1,2012,were *** included prospective and retrospective studies on patients'QOL after several types of pancreatic *** results of these primary studies were summarized *** A total of 45 articles were included in the study,of which 13 were related to pancreaticoduodenectomy(PD),seven to duodenum-preserving pancreatic head resection(DPPHR),nine to distal pancreatectomy(DP),two to central pancre-atectomy(CP),and 14 to total pancreatectomy(TP).Some studies showed that 3-6 months were needed for QOL recovery after PD,whereas others showed that 6-12 months was more *** TP and PD had similar influences on QOL,patients needed longer to recover to preoperative or baseline levels after *** QOL was better after DPPHR than ***,the superiority of the QOL between patients who underwent CP and PD remains *** decrease in exocrine and endocrine functions postoperatively was the main factor affecting the *** invasive surgery could improve patients’QOL in the early Core Tip:This review summarizes and analyzes current research results on quality of life(QOL)after pancreatic *** article covers the discussion and analysis of the QOL of various pancreatic *** kind of surgical procedure has better QOL is *** long-term benefits on QOL of minimally invasive su

关键词： Quality of life Pancreaticoduodenectomy Duodenum-preserving pancreatic head resection Distal pancreatectomy Central pancreatectomy Total pancreatectomy

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