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Chinese Journal of Polymer Science 2024年第8期42卷 1147-1155页

作者： Wen-jun Feng Yan-He wu xiao-Yang Liu Zheng-Ke Wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

Shear-thinning hydrogels have emerged for endoscopic submucosal dissection,while wound intervention after surgery has rarely been ***,a catechol-modified chitosa n hydrogel with shear-thinning property was developed for simultaneously facilitating endoscopic submucosal dissection and postoperative wound *** from the shear-thinning and self-healing characteristics,the asprepared hydrogel showed easily endoscopic *** also performed very well as submucosal cushion,which could remain above 70%after injection for 120 min in ex vivo porcine large intestine *** fact,the cushion height of normal saline dramatically decreased to 46%of the initial height at 30 *** nanoparticles encapsulated into the network endowed the hydrogel with almost reached 100%antibacterial effect against *** and *** hemolysis ratio of the hydrogel was calculated to be as low as 0.8%.Combined with good hemocompatibility and cytocompatibility,the as-prepared hydrogel displayed much higher in vivo wound closu re and healing efficacy than normal *** results demonstrated the superiority of the shear-thinning chitosan hydrogel in facilitating clinical endoscopic submucosal dissection surgery.

关键词： Shear-thinning hydrogel Endoscopic mucosal dissection Wound healing Catechol-modified chitosan Silver nanoparticles

Bolstering the Mechanical Robustness of Supramolecular Polymer Network by Mechanical Bond

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Chinese Journal of Polymer Science 2024年第10期42卷 1536-1544,I0012页

作者： Yuan-Hao Wang Jing-xi Deng jun Zhao Yi Ding Li Yang Zhao-Ming Zhang Xu-Zhou Yan School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai200240China Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong UniversityShanghai200240China

Supramolecular polymer networks(SPNs)are celebrated for their dynamic nature,yet they often exhibit inadequate mechanical *** far,the quest to bolster the mechanical resilience of SPNs while preserving their dynamic character presents a formidable ***,we introduce[2]rotaxane into SPN to serve as another cross-link,which could effectively enhance the mechanical robustness of the polymer network without losing the dynamic *** with SPN,the dually cross-linked network(DPN)demonstrates superior breaking strength,Young’s modulus,puncture force and toughness,underscoring its superior ***,the cyclic tensile tests reveal that the energy dissipation capacity of DPN rivals,and in some cases surpasses,that of SPN,owing to the efficient energy dissipation pathway facilitated by[2]*** addition,benefiting from stable topological structure of[2]rotaxane,DPN exhibits accelerated recovery from deformation,indicating superior elasticity compared to *** strategy elevates the performance of SPNs across multiple metrics,presenting a promising avenue for the development of high-performance dynamic materials.

关键词： Rotaxane cross-links Dually cross-linked network Supramolecular polymer network Host-guest recognition Dynamic materials

Advances in metal-organic framework-derived single-atom catalysts for biomedicine

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Nano Materials Science 2024年第4期6卷 396-412页

作者： Li Qiu Yingxi Lin jun Song Chen Hong Luo Rui wu Department of Ultrasound West China Second University Hospital Sichuan University Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education Sichuan University School of Materials and Energy University of Electronic Science and Technology of China Interdisciplinary Materials Research Center Institute for Advanced Study Chengdu University

As a alternative for natural enzymes, nanozymes has shown enzyme-like activity and selectivity in the field of various kinds of biomedical application, which has attracted considerable research interest. Recently, single-atom catalysts(SACs) have been extensively studied due to their similar active centers, coordination environment and better stability to natural enzymes. Metal-organic frameworks(MOFs) have been demonstrated as highly promising precursors for the synthesis of various types of SACs. MOF-derived SACs can not only significantly enhance the catalytic activity, but also improve the selectivity of nanozymes due to tunable coordination environment and structure, thereby receiving widespread attention in biomedicine. This review provided an overview of the preparation strategies for MOF-derived SACs, and then detailed the latest research progress of the SACs in the biomedical field for cancer, antibacterial, antioxidation and biosensors. Finally, the challenges and potential future opportunities of MOF-derived SACs in biomedical applications are proposed.

关键词： Biomedicine MOF-Derived SAC nanozymes Catalytic mechanisms

Computerized cognitive remediation therapy on cognitive impairment and social function in patients with chronic schizophrenia

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World Journal of Psychiatry 2024年第6期14卷 884-893页

作者： Jian-jun Hu xi-Rong Sun Shuang-Ming Ni Yan Kong Department of Psychiatry Shanghai Pudong New Area Mental Health Center(Mental Health Center of Tongji UniversityShanghai Pudong New Area Psychological Counseling Center)Shanghai 200124China

BACKGROUND Patients with schizophrenia may have various disease manifestations,most of which gradually tend toward incurable chronic decline,leading to mental *** basic symptoms of the disease can impair social function,whereas long-term hospitalization produces hospitalization syndrome,causing serious damage to social *** To investigate the effects of Computerized Cognitive Remediation Therapy(CCRT)on cognitive and social functioning in patients with chronic *** A retrospective analysis of 120 patients with chronic schizophrenia in Shanghai Pudong New Area Mental Health Center was *** were divided into an intervention group(60 cases treated with CCRT combined with conventional medication)and a control group(60 cases treated with conventional medication).After treatment,effects on cognitive function and social roles were observed in both *** Positive and Negative Syndrome Scale(PANSS)was used to assess the patients'psychiatric *** Wisconsin Card Sorting Test(WCST)was used to assess the patients'cognitive functioning,and the Social Functioning Scale for Psychiatric Inpatients(SSPI)was used to assess the social functioning of the inpatient psychiatric *** No significant differences were observed in the PANSS,WCST,and SSPI intergroup scores before treatment(P>0.05).After 2,4,and 6 wk of therapy,general psychopathological factors,positive symptoms,negative symptoms,and total PANSS scores of PANSS in the intervention group were lower than in the control group(P<0.05).After 2,4,and 6 wk of treatment,the number of false responses,number of persistent bugs,and total responses in the WCST were significantly lower in the intervention group than in the control group(P<0.05),and the amount of completed classification was significantly higher than in the control group(P<0.05).After 2,4,and 6 wk of therapy,the SSPI scores were significantly greater than those of the controls(P<0.05).After 6 wk of treatm

关键词： Computerized cognitive correction therapy Schizophrenia Cognitive function Social function Psychopathological factors

The nature of electron density enhancement over a wide altitude range during ionosphere heating experiments at EISCAT

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Earth and Planetary Physics 2024年第2期8卷 408-414页

作者： jun wu Jian wu Jie Feng QingLiang Li ShuJi Hao ZhengWen Xu HaiSheng Zhao YaBin Zhang National Key Laboratory of Electromagnetic Environment China Research Institute of Radio Wave PropagationBeijing 102206China School of Physics Xidian UniversityXi’an 710071China

During the course of ionospheric heating experiments, researchers at the European Incoherent Scatter Scientific Association (EISCAT) observed an apparent electron density enhancement. The enhancement extended over a wide range of altitudes, above the reflection altitude of the high-frequency pump wave. However, whether this enhancement actually corresponds to a true enhancement in electron density remains an open question. When the dispersion relation of ion acoustic waves is followed, the frequency ratio of the enhanced ion line to the background ion line suggests that the profile of the effective ion mass may have remained unchanged. Furthermore, the solar radio flux and ion drift velocity indicate no significant changes in the ion species and their densities. In conclusion, the electron density enhancement observed at EISCAT should not, in fact, be considered a true enhancement.

关键词： incoherent scatter radar(ISR) ionospheric heating electron density ion acoustic wave

Asymmetrical Fault Current Calculation Method and Influencing Factors Analysis of Droop-Controlled Inverters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 562-573页

作者： Huimin Zhao Zhikang Shuai jun Ge An Luo Weimin wu Z.John Shen College of Electrical and Information Engineering Hunan UniversityChangsha 410006China Electrical Engineering Department Shanghai Maritime UniversityShanghai 201306China Department of Electrical and Computer Engineering Ilinois Institute of TechnologyChicagoIL 60616 USA

Since the fault dynamic of droop-controlled inverter is different from synchronous generators (SGs), protection devices may become invalid, and the fault overcurrent may damage power electronic devices and threaten the safety of the microgrid. Therefore, it is imperative to conduct a comprehensive fault analysis of the inverter to guide the design of protection schemes. However, due to the complexity of droop control strategy, existing literatures have simplified asymmetric fault analysis of droop-controlled inverters to varying degrees. Therefore, accurate fault analysis of a droop-controlled inverter is needed. In this paper, by analyzing the control system, an accurate fault model is established. Based on this, a calculation method for instantaneous asymmetrical fault current is proposed. In addition, the current components and current characteristics are analyzed. It was determined that fault currents are affected by control loops, fault types, fault distance and nonlinear limiters. In particular, the influences of limiters on the fault model, fault current calculation and fault current characteristics were analyzed. Through detailed analysis, it was found that dynamics of the control loop cannot be ignored, the fault type and fault distance determine fault current level, and part of the limiters will totally change the fault current trend. Finally, calculation and experimental results verify the correctness of the proposed method.

关键词： Asymmetrical fault analysis droop control fault current calculation method limiter transient fault characteristics

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高校体操教学滑坡现象及其对策

浙江体育科学 1999年第3期21卷 13-15页

作者：邬锡均浙江财经学院体军部浙江杭州310012

针对当前高校体育教学改革中出现的体操教学大滑坡现象，在广泛调查的基础上，总结了体操教学滑坡现象的原因和危机感结合社会出现的“体育热”，提出了制止这种滑坡现象的必要性和可能性，并结合体操运动本身的特点及高校体育教学改革... 详细信息

针对当前高校体育教学改革中出现的体操教学大滑坡现象，在广泛调查的基础上，总结了体操教学滑坡现象的原因和危机感结合社会出现的“体育热”，提出了制止这种滑坡现象的必要性和可能性，并结合体操运动本身的特点及高校体育教学改革的需要，提出了改革学校体操教学的方案，以达到振兴体操教学的目的，为促进学校体育教学改革和推进全民健身运动而努力。

关键词：体操教学滑坡对策

Systematic study of cluster radioactivity in trans-lead nuclei with various versions of proximity potential formalisms

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Chinese Physics C 2024年第5期48卷 209-225页

作者：刘潇蒋杰栋吴喜军李小华 School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Math and Physics University of South ChinaHengyang 421001China National Exemplary Base for International Sci&Tech.Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology&Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

In this study,based on the framework of the Coulomb and proximity potential model(CPPM),we systematically investigate the cluster radioactivity half-lives of 26 trans-lead nuclei by considering the cluster preformation probability,which possesses a simple mass dependence on the emitted cluster according to *** and ***[***.61,1930(1988)].Moreover,we investigate 28 different versions of the proximity potential formalisms,which are the most complete known proximity potential formalisms proposed to describe proton radioactivity,two-proton radioactivity,αdecay,heavy-ion radioactivity,quasi-elastic scattering,fusion reactions,and other *** calculated results show that the modified forms of proximity potential 1977,denoted as Prox.77-12,and proximity potential 1981,denoted as Prox.81,are the most appropriate proximity potential formalisms for the study of cluster radioactivity,as the root-mean-square deviation between experimental data and relevant theoretical results obtained is the least;both values are *** comparison,the universal decay law(UDL)proposed by Qi et al.[***.C 80,044326(2009)],unified formula of half-lives forαdecay and cluster radioactivity proposed by Ni et al.[***.C 78,044310(2008)],and scaling law(SL)in cluster radioactivity proposed by Horoi et al.[***.G 30,945(2004)]are also *** addition,utilizing CPPM with Prox.77-12,Prox.77-1,Prox.77-2,and Prox.81,we predict the half-lives of 51 potential cluster radioactive candidates whose cluster radioactivity is energetically allowed or observed but not yet quantified in *** predicted results are in the same order of magnitude as those obtained using the compared semi-empirical and/or empirical *** the same time,the competition betweenαdecay and cluster radioactivity of these predicted nuclei is *** comparing the half-lives,this study reveals thatαdecay predominates.

关键词： cluster radioactivity half-lives Coulomb and proximity potential model

Monte Carlo method for evaluation of surface emission rate measurement uncertainty

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Nuclear Science and Techniques 2024年第7期35卷 126-136页

作者： Yuan-Qiao Li Min Lin Li-jun Xu Rui Luo Yu-He Zhang Qian-xi Ni Yun-Tao Liu China Institute of Atomic Energy Beijing102413China National Key Laboratory for Metrology and Calibration Techniques Beijing102413China Department of Radiation Oncology Hunan Cancer HospitalChangsha410031China The Affiliated Cancer Hospital of xiangya School of Medicine Central South UniversityChangsha410031China

The aim of this study is to evaluate the uncertainty of 2πα and 2πβ surface emission rates using the windowless multiwire proportional counter *** study used the Monte Carlo method (MCM) to validate the conventional Guide to the Expression of Uncertainty in Measurement (GUM) method.A dead time measurement model for the two-source method was established based on the characteristics of a single-channel measurement system,and the voltage threshold correction factor measurement function was indirectly obtained by fitting the threshold correction *** uncertainty in the surface emission rate was calculated using the GUM method and the law of propagation of *** MCM provided clear definitions for each input quantity and its uncertainty distribution,and the simulation training was realized with a complete and complex mathematical *** results of the surface emission rate uncertainty evaluation for four radioactive plane sources using both methods showed the uncertainty’s consistency E_(n)<0.070 for the comparison of each source,and the uncertainty results of the GUM were all lower than those of the ***,the MCM has a more objective evaluation process and can serve as a validation tool for GUM results.

关键词： Surface emission rate Monte Carlo method Metrology Probability distribution function Dead time Low-energy loss correction Least-squares method

Simple chemical synthesis and isotropic negative thermal expansion in MHfF_(6)(M=Ca,Mn,Fe,and Co)

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Nano Research 2024年第3期17卷 2195-2203页

作者： Yongqiang Qiao Sen Zhang Peixian Zhang Juan Guo Andrea Sanson xi Zhen Kaiyue Zhao Qilong Gao jun Chen Key Laboratory of Materials Physics of Ministry of Education and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Department of Physics and Astronomy University of PadovaPadova I-35131Italy Beijing Advanced Innovation Center for Materials Genome Engineering Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China

The rapid progress of modern technologies has accelerated the prominence of thermal expansion mismatch between materials,and tunable thermal expansion materials will be a powerful safeguard against this ***,isotropic MHfF_(6)(M=Ca,Mn,Fe,and Co)compounds with tunable thermal expansion have been produced via a low-cost synthetic method and *** utilizing temperature dependent X-ray diffraction(XRD)and Raman spectroscopy,combined with first principles calculations,it was revealed that the transverse thermal vibrations of the F atoms are dominated by low-frequency phonons with negative Grüneisen parameters and are therefore the origin of the negative thermal expansion(NTE).Very interestingly,with the increase of the M atomic number,the metal…F atomic linkages become stiffer,reducing the number of vibrational modes with negative Grüneisen parameters,so that the strong NTE can be gradually adjusted to moderate NTE and to near zero thermal *** present study achieves the tunable thermal expansion in a new compound family and shed light on the internal mechanism from the perspective of lattice vibrational dynamics.

关键词： negative thermal expansion fluorides chemical synthesis nanosheet structure first principles calculations