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Preparation and Structure-Property Regulation Mechanism of Reversible Thermochromic Polydiacetylene

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Chinese Journal of Polymer Science 2024年第8期42卷 1111-1121页

作者： Zhi-Qing Ge Shuo Yan Zu-Xiong Pan shan Lei Xuan-Zhi Mao Chu Zhao Mo-zhen Wang Xue-Wu Ge Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Marshall Laboratory of Biomedical Engineering International Cancer CenterLaboratory of Evolutionary Theranostics(LET)School of Biomedical EngineeringShenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The thermochromic mechanism and the structure-property regulation principle of reversible thermochromic polydiacetylene(PDA)materials have always been a challenging *** this work,a series of diacetylene monomers(m-PCDA)containing phenyl and amide or carboxyl groups were synthesized from 10,12-pentacosadiynoic acid(PCDA)through the esterification or amidation *** effects of the number and the distribution of the functional groups in m-PCDA molecules on their solid-state polymerization capability,and the thermochromic mechanism of their corresponding polymers(m-PDA)were investigated and discussed in *** results show that the m-PCDA monomers containing both benzene ring and groups that can form hydrogen bonding interactions have strong intermolecular interaction,and are easy to carry out the solid phase polymerization under 254-nm UV irradiation to obtain the corresponding new thermochromic m-PDA *** thermochromic behavior of m-PDA depends on its melting *** initial color-change temperature(blue to red)is determined by the onset melting tem perature,and the temperature range in which reversible color recovery can be achieved by repeat heating-cooling treatment is determined by its melting *** to the proposed thermochromic mechanism of PDA,various new PDA materials with precise thermochromic temperatu res and reversible thermochromic temperature ra nges can be designed and synthesized through the appropriate introduction of benzene ring and groups that can form hydrogen bonding interactions into the molecular structure of linear diacetylene *** work provides a perspective to the precise molecular structure design and the property regulation of the reversible thermochromic PDA materials.

关键词： Polydiacetylene Thermochromism Hydrogen bonding Chemical modification

The Besov Space B_1^(0.1) on Domains

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Acta Mathematica Sinica,English Series 2001年第2期17卷 181-196页

作者： Yi Qing GUI shan zhen lu Da Chun YANG Department of Mathematics. Beijing Normal University. Beijing 100875. P. R. China Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

Let Ω be a bounded Lipschitz domain. Define B1,r0.1（Ω）={f∈L1（Ω）: there is an F∈ B10.1（Rn） such that F|Ω=f| and B1,z0.1（Ω）={f∈B10.1（Rn）: f=0 on Rn\}. In this paper, the authors establish the atomic decompositions of these spaces. As by-products, the authors obtained the regularity on these spaces of the solutions to the Dirichlet problem and the Neumann problem of the Laplace equation on R+n.

关键词： Besov space Lipschitz domain Atom Laplace equation

High-Performance Recyclable Furan-based Epoxy Resin and Its Carbon Fiber Composites with Dense Hydrogen Bonding

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Chinese Journal of Polymer Science 2024年第1期42卷 73-86,I0008页

作者： Chang-Bo Zhao lu-Kun Feng Hui Xie Ming-Liang Wang Bing Guo Zhi-Yong Xue Cai-zhen Zhu Jian Xu Advanced Materials Research Institute North China Electric Power UniversityBejing 102206China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology and Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive ApplicationHarbin Institute of TechnologyShenzhen 518055China

The emerging biomass-based epoxy vitrimers hold great potential to fulfill the requirements for sustainable development of *** the existence of dynamic chemical bonds in vitrimers often reduces both the thermal and mechanical properties of epoxy resins, it is challenging to produce recyclable epoxy vitrimers with both excellent mechanical properties and good thermal stability. Herein, a monomer 4-(((5-(hydroxymethyl)furan-2-yl)methylene)amino)phenol(FCN) containing furan ring with potential to form high density of hydrogen bonding among repeating units is designed and copolymerized with glycerol triglycidyl ether to yield epoxy resin(FCN-GTE), which intrinsically has dual hydrogen bond networks, dynamic imine structure and resultant high performance. Importantly, as compared to the BPA-GTE, the FCN-GTE exhibits significantly improved mechanical properties owing to the increased density of hydrogen bond network and physical crosslinking interaction. Furthermore, density functional theory(DFT) calculation and in situ FTIR analysis is conducted to decipher the formation mechanism of hydrogen bond network. In addition, the FCN-GTE possesses superior UV shielding, chemical degradation, and recyclability because of the existence of abundant imine bonds. Notably, the FCN-GTE-based carbon fiber composites could be completely recycled in an amine *** study provides a facile strategy for synthesizing recyclable biomass-based high-performance epoxy vitrimers and carbon fiber composites.

关键词： Furan Hydrogen bond network Dynamic Schiff base Carbon fiber composites Recycling

Study on tungsten sintering temperature field based on electromagnetic simulation and computational fluid dynamics

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Tungsten 2024年第2期6卷 355-366页

作者： lu-Yan Wang Yue-Guang Yu Jian-Xin Dong Kai-Ping Du shan-Yu Liu Cao-Bing Li University of Science and Technology Beijing Beijing 100083China BGRIMM Technology Group Beijing 100160China China Iron&Steel Research Institute Group Beijing 100081China

In order to study the influence of various sintering variables more intuitively and clearly,electromagnetic field analysis and computational fl uid dynamics are used to analyze the infl uence of gas flow,heating power and other process parameters on the temperature range of medium-frequency sintering in this *** results indicate that the uniformity of temperature fi eld is determined by the gas flow rate and heating *** the heating power is 50 kW,the stable temperature drops about 10 K for every 1 m^(3)·h^(−1)increase of hydrogen *** peak value of the maximum temperature diff erence on the tungsten rods gradually increases with the increase of the hydrogen flow rate,and it appears slightly *** temperature distribution of tungsten rods in furnace is similar with diff erent hydrogen flow *** the same time,the closer to the furnace wall,the higher the temperature of the tungsten *** temperature diff erence between tungsten rods mainly occurred within 1 h after the beginning of *** the heating power can improve the stable temperature,but has little eff ect on the heating *** heating power can increase the peak value of the maximum temperature diff erence on the tungsten rods,but has little eff ect on the occurrence time of the peak value of the maximum temperature diff erence on the tungsten *** the heating power will increase the temperature diff erence of a single tungsten rod,but the temperature diff erence of a single tungsten rod never exceeds 65 *** study can be used to guide the process optimization *** with numerical simulation calculation,the sintering parameters with low energy consumption and high temperature uniformity can be quickly and eff ectively found,thus improving the microstructure and properties of sintered tungsten products.

关键词： Tungsten products Sintering Hydrogen flow rate Heating power

Quantum key distribution over a mimicked dynamic-scattering channel

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Science China(Information Sciences) 2024年第4期67卷 323-330页

作者： Qi-Hang lu Fang-Xiang WANG Wei CHEN Hai-Yang FU Yin-Jie lu Shuang WANG De-Yong HE zhen-Qiang YIN Guang-Can GUO zheng-Fu HAN CAS Key Laboratory of Quantum Information University of Science and Technology of China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China

Free-space quantum key distribution(QKD) plays an important role in the global quantum network. However, free space channels suffer from the atmospheric turbulence and scattering effects of haze,fog, and dust, which significantly weaken the performance of QKD or even block the secure quantum ***, we prove the performance of QKD over a dynamic scattering channel can be enhanced significantly using a fast wavefront shaping technique. The system achieves on average 10-dB enhancement of quantum transmission efficiency and establishes a secure quantum link for QKD. Our work demonstrates the feasibility of QKD through free-space dynamic scattering channels and enhances the deployment capability of complex-channel QKD system.

关键词： quantum key distribution free space channel channel turbulence channel scattering wavefront shaping

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Efficacy and safety of Yiqi Peiyuan granules for improving the short-term prognosis of patients with acute kidney injury:A multicenter,double-blind,placebo-controlled,randomized trial

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Journal of Integrative Medicine 2024年第3期22卷 279-285页

作者： Jia-jia Wu Tian-yi Zhang Ying-hui Qi Min-yan Zhu Yan Fang Chao-jun Qi Li-ou Cao Ji-fang lu Bo-han lu lu-min Tang Jian-xiao Shen shan Mou Department of Nephrology Molecular Cell Lab for Kidney DiseaseShanghai Peritoneal Dialysis Research CenterUremia Diagnosis and Treatment CenterRenji Hospital Affiliated to Shanghai Jiaotong University School of MedicineShanghai 200127China Department of Nephrology Shanghai Pudong New Area Punan HospitalShanghai 200125China Department of Nephrology Ningbo Hangzhou Bay HospitalNingbo 315336Zhejiang ProvinceChina

Background:Yiqi Peiyuan(YQPY)prescription,a composite prescription of traditional Chinese medicine,has been used to prevent or delay the continued deterioration of renal function after acute kidney injury(AKI)in some institutions and has shown considerable ***:This is the first randomized controlled trial to assess efficacy and safety of YQPY for improving short-term prognosis in adult patients with ***,setting,participants and interventions:This is a prospective,double-blind,multicenter,randomized,and placebo-controlled clinical trial.A total of 144 enrolled participants were randomly allocated to two groups according to a randomization ***,caregivers and investigators assessing the outcomes were blinded to group *** in the YQPY group received 36 g YQPY granules twice a day for 28 *** in the placebo group received a placebo in the same dose as the YQPY *** outcome measures:The primary outcome was the change in the estimated glomerular filtration rate(eGFR)between baseline and after 4 and 24 weeks of *** secondary outcomes were the change of serum creatinine(Scr)level between baseline and after treatment,and the incidence of endpoint events,defined as eGFR increasing by more than 25%above baseline,eGFR>75 mL/min per1.73 m2or the composite endpoint,which was defined as the sum of patients meeting either of the above ***:Data from a total of 114 patients(59 in the YQPY group and 55 in the control group)were *** mean changes in eGFR and Scr in weeks 4 and 24 had no difference between the two *** further subgroup analysis(22 in the YQPY group and 31 in the control group),the mean change in eGFR after treatment for 4 weeks was 27.39 mL/min per 1.73 m2in the YQPY group and 5.78 mL/min per1.73 m2in the placebo group,and the mean difference between groups was 21.61 mL/min per 1.73 m2(P<0.001).Thirteen(59.1%)patients in the YQPY group and 5(16.1%)in the placebo g

关键词： Chinese herbal medicine Randomized controlled trial Acute kidney injury Renal function

Differentiation and immunosuppressive function of CD19^(+)CD24^(hi)CD27^(+) regulatory B cells are regulated through the miR-29a-3p/NFAT5 pathway

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 472-480页

作者： Jin-Yang Li Tian-Shuo Feng Ji Gao Xin-Xiang Yang Xiang-Cheng Li zhen-Hua Deng Yong-Xiang Xia zheng-shan Wu Hepatobiliary Center the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Key Laboratory of Liver Transplantation Chinese Academy of Medical SciencesNanjing 210029China NHC Key Laboratory of Living Donor Liver Transplantation Nanjing Medical UniversityNanjing 210029China

Background: Regulatory B cells(Bregs) is an indispensable element in inducing immune tolerance after liver transplantation. As one of the microRNAs(miRNAs), mi R-29a-3p also inhibits translation by degrading the target mRNA, and yet the relationship between Bregs and mi R-29a-3p has not yet been fully explored. This study aimed to investigate the impact of miR-29a-3p on the regulation of differentiation and immunosuppressive functions of memory Bregs(m Bregs) and ultimately provide potentially effective therapies in inducing immune tolerance after liver transplantation. Methods: Flow cytometry was employed to determine the levels of Bregs in peripheral blood mononuclear cells. TaqMan low-density array miRNA assays were used to identify the expression of different miRNAs, electroporation transfection was used to induce mi R-29a-3p overexpression and knockdown, and dual luciferase reporter assay was used to verify the target gene of miR-29a-3p. Results: In patients experiencing acute rejection after liver transplantation, the proportions and immunosuppressive function of m Bregs in the circulating blood were significantly impaired. mi R-29a-3p was found to be a regulator of m Bregs differentiation. Inhibition of miR-29a-3p, which targeted nuclear factor of activated T cells 5(NFAT5), resulted in a conspicuous boost in the differentiation and immunosuppressive function of m Bregs. The inhibition of mi R-29a-3p in CD19~+ B cells was capable of raising the expression levels of NFAT5, thereby promoting B cells to differentiate into m Bregs. In addition, the observed enhancement of differentiation and immunosuppressive function of m Bregs upon mi R-29a-3p inhibition was abolished by the knockdown of NFAT5 in B cells. Conclusions: mi R-29a-3p was found to be a crucial regulator for m Bregs differentiation and immunosuppressive function. Silencing mi R-29a-3p could be a potentially effective therapeutic strategy for inducing immune tolerance after liver transplantation.

关键词： Regulatory B cells miR-29a-3p NFAT5 Liver transplantation

Male reproductive function before and after the adjustment of the COVID-19 prevention policy:a multicenter study in China

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Asian Journal of Andrology 2024年第3期26卷 308-314页

作者： Jian-zheng Li Han Wu Li Wang Yun-shan Wang Feng Kong Long-Qiao Cao Ming Liang Xiong Wang Ming-zhen Yuan shandong Provincial Hospital Affiliated to shandong First Medical University Jinan 250000China Institute of Women Children and Reproductive HealthShandong UniversityJinan 250012China Engineering Laboratory of Urinary Organ and Functional Reconstruction of shandong Province Jinan 250000China The First People’sHospital of Jining Jining 272000China Department of Reproductive Medicine The Second Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan 250000China Reproductive Medicine Center Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantai 264000China

At the end of 2022,the adjustment of the coronavirus disease 2019(COVID-19)pandemic control policy in China resulted in alarge-scale increase in public *** compare the fertility parameters of male patients before and after the adjustments ofthe COVID-19 pandemic control policy in China,we collected data on patients’medical histories and laboratory examinations ontheir first visits between June 2022 and March 2023 in five different *** were divided into five groups according tothe timeline of the policy *** data we collected from male patients included semen quality and serum reproductivehormone levels,and intergroup comparisons were made using the Mann–Whitney U and Chi-square *** total,16784 casesunderwent regular semen analysis,11180 had sperm morphology assessments,and 7200 had reproductive hormone *** showed declining trends in semen volume,sperm motility,and the progressive sperm motility rate after the policy *** comparison revealed an initial decrease and gradual recovery in progressive motility *** morphology analysisshowed increased neck and tail abnormalities after the policy *** significant change in hormone levels was *** the adjustment of the COVID-19 prevention policy in China,a decline in sperm motility and morphology was *** trend may gradually recover over 2 *** the policy adjustment,reproductive hormone levels were relatively stablethroughout,except for an increase in luteinizing hormone(LH).These changes in semen parameters suggest that the policyadjustment had a short-to medium-term impact on male reproductive function.

关键词： COVID-19 multicenter study reproduction SARS-CoV-2 semen analysis

Bioinspired polysaccharide-based nanocomposite membranes with robust wet mechanical properties for guided bone regeneration

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National Science Review 2024年第3期11卷 215-226页

作者： Jian-Hong Xiao zhen-Bang Zhang JiaHao Li Si-Ming Chen Huai-Ling Gao YinXiu Liao lu Chen ZiShuo Wang YiFan lu Yuanzhen Hou HengAn Wu DuoHong Zou Shu-Hong Yu Department of Chemistry New Cornerstone Science Laboratory Institute of Biomimetic Materials&Chemistry Anhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of China Department of Dental Implant Center Stomatologic Hospital and College Key Laboratory of Oral Diseases Research of Anhui Province Anhui Medical University CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern Mechanics CAS Center for Excellence in Complex System Mechanics University of Science and Technology of China Department of Oral Surgery College of Stomatology National Clinical Research Center for Oral DiseasesShanghai Key Laboratory of Stomatology Shanghai Research Institute of Stomatology Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Institute of Innovative Materials(I2M) Department of Chemistry Department of Materials Science and Engineering Southern University of Science and Technology

Polysaccharide-based membranes with excellent mechanical properties are highly desired. However, severe mechanical deterioration under wet conditions limits their biomedical applications. Here, inspired by the structural heterogeneity of strong yet hydrated biological materials, we propose a strategy based on heterogeneous crosslink-and-hydration（HCH） of a molecule/nano dual-scale network to fabricate polysaccharide-based nanocomposites with robust wet mechanical properties. The heterogeneity lies in that the crosslink-and-hydration occurs in the molecule-network while the stress-bearing nanofiber-network remains unaffected. As one demonstration, a membrane assembled by bacterial cellulose nanofiber-network and Ca2+-crosslinked and hydrated sodium alginate molecule-network is designed. Studies show that the crosslinked-and-hydrated molecule-network restricts water invasion and boosts stress transfer of the nanofiber-network by serving as interfibrous bridge. Overall, the molecule-network makes the membrane hydrated and flexible; the nanofiber-network as stress-bearing component provides strength and *** HCH dual-scale network featuring a cooperative effect stimulates the design of advanced biomaterials applied under wet conditions such as guided bone regeneration membranes.

关键词： bioinspiration heterogeneous crosslink-and-hydration dual-scale network nanocomposite membrane wet mechanical properties guided bone regeneration