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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

Crystal structures and electronic properties of BaC_2 isomers by theoretical study based on DFT

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science china Chemistry 2008年第6期51卷 545-550页

作者： FENG Jing1,xiAO Bing2 & CHEN JingChao1 1 Key Laboratory of Advanced Materials of Precious-Nonferrous Metals,Education Ministry of china,and Key Lab of Advanced Materials of Yunnan Province,Kunming university of science and Technology,Kunming 650093,china 2 School of Materials science and Engineering,xi’an Jiaotong university,xi’an 710049,china 1. Key Laboratory of Advanced Materials of Precious-Nonferrous Metals Education Ministry of China Kunming China 3. Key Lab of Advanced Materials of Yunnan Province Kunming University of Science and Technology Kunming 650093 China 2. School of Materials science and Engineering Xi’an Jiaotong University Xi’an 710049 China

Band structures and electronic properties of two BaC2 isomers were calculated by using density func-tional theory(DFT) *** ionic bond features are all typical between cation(Ba) and anion clusters(C2) in both structures of the ***,a much stronger covalent bond exists in anion clusters which can be seen by inspecting the electron distribution contour that has a dull bell like shape between two carbon *** shortest distance between Ba2+ and C22? and the bond length in anion clusters are different in these isomers of BaC2,which are 0.2945 nm and 0.1185 nm for the structure with the I4/mmm space group and 0.2744 and 0.1136 nm with the C2/c type,*** structures were clarified by combining the DOS to indicate the ionic bonding features more *** analysis provided further evidence on these *** calculation results reveal that the transition temperature of these two polymorphs of BaC2 locates near 132 K,which is consistent with the recent experimental results.

关键词： functional materials metal diaries phase transition electron density first principle calculation orbital bonding state

Liquid metal biomaterials: translational medicines,challenges and perspectives

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National science Review 2024年第2期11卷 264-284页

作者： Hanchi Xu Jincheng Lu Yikuang xi Xuelin Wang Jing Liu Department of Biomedical Engineering School of Medicine Tsinghua University Beijing Tsinghua changgung Hospital School of Clinical Medicine Tsinghua University Shanghai World Foreign Language Academy Beijing Advanced Innovation Center for Biomedical Engineering School of Engineering MedicineBeihang University Beijing Key Lab of Cryo-Biomedical Engineering and Key Lab of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Until now, significant healthcare challenges and growing urgent clinical requirements remain incompletely addressed by presently available biomedical materials. This is due to their inadequate mechanical compatibility, suboptimal physical and chemical properties, susceptibility to immune rejection, and concerns about long-term biological safety. As an alternative, liquid metal(LM) opens up a promising class of biomaterials with unique advantages like biocompatibility, flexibility, excellent electrical conductivity,and ease of functionalization. However, despite the unique advantages and successful explorations of LM in biomedical fields, widespread clinical translations and applications of LM-based medical products remain limited. This article summarizes the current status and future prospects of LM biomaterials, interprets their applications in healthcare, medical imaging, bone repair, nerve interface, and tumor therapy, *** to translate LM materials into medicine and obstacles encountered in practices are *** that, we outline a blueprint for LM clinics, emphasizing their potential in making new-generation artificial organs. Last, the core challenges of LM biomaterials in clinical translation, including bio-safety,material stability, and ethical concerns are also discussed. Overall, the current progress, translational medicine bottlenecks, and perspectives of LM biomaterials signify their immense potential to drive future medical breakthroughs and thus open up novel avenues for upcoming clinical practices.

关键词： liquid metal biomaterials translational medicine clinical device healthcare therapeutics

ON THE CONVERGENCE OF SAMPLING ALGORITHMS FOR SOWING DYNAMIC STOCHASTIC PROGRAMMING

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Systems science and Mathematical sciences 2000年第4期13卷 397-406页

作者： CHEN Zhiping (faculty of science, xi’an Jiaotong university, xi’an 710049, china) 西安交通大学理学院陕西西安 710049

After describing a general sampling discretization algorithm for multistage continuous stochastic programming problems, we prove the global convergence of the al- gorithm under suitable conditions. The convergence of most available algorithms as well as new algorithms can thus be derived or improved as a special case of this general result.

关键词： Dynamic stochastic programming sampling tree normal integrand equi- lower semicontinuity epi-convergence.

Three-dimensional cell-based strategies for liver regeneration

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BIOCELL 2024年第7期48卷 1023-1036页

作者： DAN GUO xi xiA JIAN YANG Liver Transplant Center Transplant CenterWest China HospitalSichuan UniversityChengdu610041China Frontiers Medical Center Tianfu Jincheng LaboratoryChengdu610212China

Liver regeneration and the development of effective therapies for liver failure remain formidable challenges in modern *** recent years,the utilization of 3D cell-based strategies has emerged as a promising approach for addressing these urgent clinical *** review provides a thorough analysis of the application of 3D cell-based approaches to liver regeneration and their potential impact on patients with end-stage liver ***,we discuss various 3D culture models that incorporate hepatocytes and stem cells to restore liver function and ameliorate the consequences of liver ***,we explored the challenges in transitioning these innovative strategies from preclinical studies to clinical *** collective insights presented herein highlight the signiﬁcance of 3D cell-based strategies as a transformative paradigm for liver regeneration and improved patient care.

关键词： Three-Dimensional Liver regeneration Organoids Stem cells Cell therapy

LINEAR ACTIVE STRUCTURES AND MODES (Ⅰ) —BASIC CONCEPTS AND PROPERTIES

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Applied Mathematics and Mechanics(English Edition) 2004年第8期25卷 845-853页

作者：张景绘龚靖School of Civil Engineering and Mechanics xi'an Jiaotong university xi'an 710049 P.R.china Department of Civil Engineering Northeast china Institute of Electric Power Jilin 132012 P.R.china 王永刚School of Civil Engineering and Mechanics xi'an Jiaotong university xi'an 710049 P.R.china School of science chang'an university xi'an 710064 P.R.china School of Civil Engineering and Mechanics Xi'an Jiaotong University Xi'an 710049 P.R.China

Some basic concepts about the active structures were firstly explained, and the main subjects to study in the field of active structure dynamics were synthesized. For the linear active structures, the annotations on the modes were done in detail. The physical meanings of the right and left eigenvectors were explained. The right eigenvectors are the modal shapes and the modal responses of an active structure depend on the left ones. The adjoint structure of an active structure was defined and the reciprocity theorem was interpreted. For two active structures, which are adjoint to each other and with the reciprocal gain-matrices, the right and left eigenvector are reciprocal. The relationship between an active structure and the corresponding passive structure is expressed with the transfer functions, which is employed to resolve the estimation problems.

关键词： active structure vibration control smart structure mode

Restraining growth of Zn dendrites by poly dimethyl diallyl ammonium cations in aqueous electrolytes

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Rare Metals 2024年第8期43卷 3735-3747页

作者： xiang-xin Zhang Yuan-Qiang Chen chang-xin Lin Yuan-Sheng Lin Guo-Lin Hu Yong-Chuan Liu xi-Lai Xue Su-Jing Chen Zhan-Lin Yang Bai-Sheng Sa Yi-Ning Zhang Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Helmholtz Institute Ulm(HIU) 89081 UlmGermany Karlsruhe Institute of Technology(KIT) 76021 KarlsruheGermany College of Materials science and Engineering Fuzhou UniversityFuzhou350108China

Metallic zinc is an excellent anode material for Zn-ion batteries,but the growth of Zn dendrite severely hinders its practical ***,an efficient and economical cationic additive,poly dimethyl diallyl ammonium(PDDA) was reported,used in aqueous Zn-ion batteries electrolyte for stabilizing Zn *** growth of zinc dendrites can be significantly restrained by benefiting from the pronounced electrostatic shielding effect from PDDA on the Zn metal ***,the PDDA is preferentially absorbed on Zn(002) plane,thus preventing unwanted side reactions on Zn *** to the introduction of a certain amount of PDDA additive into the common ZnSO_(4)-based electrolyte,the cycle life of assembled Zn‖Zn cells(1 mA·cm^(-2) and 1 mAh·cm^(-2)) is prolonged to more than 1100 *** response to the perforation issue of Zn electrodes caused by PDDA additives,the problem can be solved by combining foamy copper with zinc *** real application,Zn-ion hybrid supercapacitors and MnO_(2)‖Zn cells were assembled,which exhibited excellent cycling stability with PDDA *** work provides a new solution and perspective to cope with the dendrite growth problem of Zn anode.

关键词： PDDA Electrostatic shielding effect Zn anode Zn dendrites

Durability of Asphalt Mixture in Different Corrosion Solution

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Journal of Wuhan university of Technology(Materials science) 2011年第6期26卷 1200-1204页

作者：陈拴发关博文 Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang’an University School of Materials science and Engineering Chang’an University

The corrosion to asphalt mixture under different kinds of corrosion solution, such as pH=2 solution, pH=12 solution, pH = 12 solution and 10% Na2SO4 solution, was studied. The performance attenuation of asphalt mixture was analyzed under the normal environment and the freeze-thaw environment, and the analysis was given on the sensitivity of the test results to the evaluation index. The experimental results show that the performance of asphalt mixture is attenuated faster under the acidic solution, alkaline solution and sulfate solution. Corrosion factor Kc, freeze-thaw corrosion factor Kf, and freeze-thaw effect factor Kfc are proposed to evaluate asphalt mixture resistance to corrosion in different kinds of corrosion solution. The values of Kc and Kfc decrease with the increasing of corrosion time. The change rule of Kf show that the rate of corrosion is decreased by the action of freeze-thaw in acidic solution and in alkaline solution, but is increased by the action of freeze-thaw in sulfate solution. The microscopic analysis indicates that acid solution reacts with aggregate of asphalt mixture, alkaline solution reacts with asphalt cement of asphalt mixture, the surface tension of sulfate solution and crystallization of sulfate are the main reasons which weak the performance of asphalt mixture.

关键词： asphalt mixture corrosion damage corrosion mechanism corrosion evaluation

Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

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Nuclear science and Techniques 2024年第2期35卷 145-159页

作者： Yan-Yan Ding Yang-Bo Nie Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang xin-Yi Pan chang-Lin Lan Jie Ren xi-Chao Ruan Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Nuclear science and Technology Lanzhou UniversityLanzhou 730000China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 62100China

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the china Institute of Atomic *** leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight *** samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 *** leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and *** on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were *** results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

关键词： Leakage neutron spectra Uranium D-T neutron source Evaluated nuclear data