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Molecular Chain Flexibility and Dielectric Loss at High-Frequency:Impact of Ester Bond Arrangement in Poly(ester imide)s

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Chinese Journal of Polymer Science 2024年第8期42卷 1122-1133页

作者： Ya-Dong Li Hong Li Lu-kun Feng Feng Bao Ming-Liang Wang Cai-Zhen Zhu Zhao-Hui Zheng Xiao-Bin Ding jian Xu Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100081China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer ***,it has been theorized that rigid molecular chains lead to lower dielectric ***,the validity of this proposition at high frequencies remains *** scrutinize the correlation between chain flexibility and dielectric properties,we synthesized six poly(ester imide)s(PEIs)with systematically varied molecular chain flexibilities by modifying the ester's substitution on the aromatic *** introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor(D_(f)),ranging from 0.0021 to 0.0038 at 10 GHz in dry *** dry D_(f)displayed a pattern consistent with volume polarizability(P/V).Unexpectedly,PI-mmm-T,featu ring the most flexible molecular chain,exhibited the lowest dielectric loss under both dry(0.0021@10 GHz)and hygroscopic(0.0029@10 GHz)***,the observed increase in D_(f)after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic *** simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains,after close stacking,impede the entry of water *** sacrificing high-temperature resistance,the precursor exhibited enhanced solubility properties and could be processed into high-quality *** research unveils new insights into the relationship between flexibility and highfrequency dielectric loss,offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.

关键词： 5G communications Poly(ester imide)s Molecular chain flexibility Dielectric properties Humidity absorption

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Portable fluorogenic probe for monitoring of volatile amine vapour and food spoilage

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Chinese Chemical Letters 2024年第3期35卷 257-261页

作者： jian-Hao Zhao Wen-Xing Xu Bin Li Wei Xu Wu-kun Zhang Ming-Shuai Yuan Hui-Zi Li Qing-Guo He Xiang Ma jian-Gong Cheng Yan-Yan Fu State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of the Chinese Academy of SciencesBeijing 100039China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

There are urgent needs of volatile amine gas sensors with high-performance in food quality control,disease monitoring and environmental ***-film fluorescent probe is suitable for amine vapour sensing due to its high sensitivity,high selectivity,and no polluting ***,a novel fluorescent probe based on indacenodithiophene structure withπconjugated system was designed and *** experimental results show that the films prepared by this material exhibit rapid and distinct fluorescence quenching after being exposed to saturated vapours of primary amine,secondary amine and tertiary amine represented by n-propylamine,diethylamine and trimethylamine,*** quenching of fluorescence is 84%,87%and 96%,respectively,within 10 *** detection mechanism of probe for primary amine is based on specific chemical reaction,while the detection mechanism for secondary amine and tertiary amine is intramolecular charge *** experiments show that the detection limit of the fluorescent probe for trimethylamine,an important marker of food spoilage,could reach 4.610 ***-site detection based on spoilage of small yellow croaker suggests the material possesses the potential for food freshness *** simple fluorogenic probe is an original approach to simplify real-time visual monitoring of volatile amine vapour.

关键词： Fluorescent probe Volatile amine Gas sensing Trimethylamine Food spoilage

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Major Clinical Features and Epidemic Characteristics of Erosive Vulvar Lichen Planus:A Retrospective Analysis

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International Journal of Dermatology and Venereology 2024年第2期7卷 94-98页

作者： Ya-kun Shao Kai-Lyu Sun Min Yang Wan Liu Yu Fu jian-Min Chang Department of Dermatology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China

Objective:Vulvar lichen planus(VLP),especially erosive VLP(EVLP),seriously affects women’s physiological function and quality of life.A retrospective analysis of erosive vulvar lichen planus(EVLP)was performed to raise awareness on this chronic,deforming,and painful vulvar ***:This observational retrospective study involved 40 patients with EVLP among 1,368 patients with vulvar disease from 2017 to *** patients’vulvar clinical features and extravulvar mucosal involvement were *** patients’pain and quality of life were evaluated with the numeric rating scale and the Dermatology Life Quality Index(DLQI),*** characteristics were reported using frequencies and proportions for categorical *** variables are expressed as mean±standard *** association between NRS score for pain and DLQI score was analyzed by Pearson’s correlation ***:EVLP accounted for 2.9%(40/1,368)of all cases of vulvar disease,and the median age at onset was 42 *** mostly occurred on the labia minora and ***(20/40)of the patients had extravulvar mucosal ***(42.5%)patients had oral lichen planus,and seven(17.5%)patients were diagnosed with vulvovaginal-gingival *** numeric rating scale score showed that 47.5%(19/40)of patients experienced mild pain,whereas 12.5%(5/40)described the pain as ***-one patients(77.5%,31/40)had dyspareunia,and nine patients had aggravated pain after sexual *** mean DLQI score was 9.1±6.0,with 37.5%(15/40)of patients indicating that EVLP had severely affected their *** numeric rating scale score for pain was significantly correlated with the DLQI score(P=0.007).Conclusion:EVLP can affect the quality of women’s lives and cause severe deformations and painful architectural *** description of the characteristics of EVLP in this report will benefit the diagnosis and early treatment of this disease.

关键词： erosive vulvar lichen planus multiple mucosal involvement pain assessment quality of life Dermatology Life Quality Index numeric rating scale

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Computer-aided molecular design and optimization of potent inhibitors disrupting APC-Asef interaction

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2631-2645页

作者： Xuefei Wang Zeqian Du Yuegui Guo Jie Zhong kun Song Junyuan Wang jianqiang Yu Xiuyan Yang Chen-Ying Liu Ting Shi jian Zhang Department of Pathophysiology Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of EducationShanghai Jiao Tong UniversitySchool of MedicineShanghai 200025China Key Laboratory of Protection Development and Utilization of Medicinal Resources in Liupanshan AreaMinistry of EducationPeptide&Protein Drug Research CenterSchool of PharmacyNingxia Medical UniversityYinchuan 750004China State Key Laboratory of Microbial Metabolism Joint International Research Laboratory of Metabolic and Developmental SciencesSchool of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Department of Colorectal and Anal Surgery Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Basic Science Research Center Base(Pharmaceutical Science) Yantai UniversityYantai 264005China Medicinal Chemistry and Bioinformatics Center Shanghai Jiao Tong UniversitySchool of MedicineShanghai 200025China State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjing 210023China

Colorectal cancer(CRC)is the second leading cause of cancer mortality *** initial diagnosis,approximately 20%of patients are diagnosed with metastatic CRC(mCRC).Although the APC-Asef interaction is a well-established target for mCRC therapy,the discovery and development of effective and safe drugs for mCRC patients remains an urgent and challenging *** this study,we identified a novel structural scaffold based on MAI inhibitors,the first-in-class APC-Asef inhibitors we reported *** model-driven optimizations of the N-terminal cap and experimental evaluations of inhibitory activity were performed,and 24-fold greater potency was obtained with the best inhibitor compared to the parental *** addition,the cocrystal structure validated that the two-layerπ-πstacking interactions were essential for inhibitor stabilization in the bound ***,in vitro and in vivo studies have demonstrated that novel inhibitors suppressed lung metastasis in CRC by disrupting the APC-Asef *** results provide an intrinsic structural basis to further explore drug-like molecules for APC-Asef-mediated CRC therapy.

关键词： APC-Asef Peptidomimetic Computer-aided molecular design ONIOM model π-πstacking Metastatic colorectal cancer

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Mitochondria-targeted nano-AIEgens as a powerful inducer for evoking immunogenic cell death

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Chinese Chemical Letters 2024年第5期35卷 338-343页

作者： kun-Heng Li Hong-Yang Zhao Dan-Dan Wang Ming-Hui Qi Zi-jian Xu Jia-Mi Li Zhi-Li Zhang Shi-Wen Huang Key Laboratory of Biomedical Polymers of Ministry of Education Department of ChemistryWuhan UniversityWuhan 430072China

AIEgens can serve as an effective platform for the construction of photosensitizer-based immunogenic cell death(ICD)*** date,several mitochondria or endoplasmic reticulum(ER)-targeted aggregationinduced emission(AIE)molecules have been developed and have evoked massive ICD in ***,due to the complex physicochemical environment in cells,these small AIE molecules cannot maintain a stable aggregate state,which not only affects the fluorescence intensity of the photosensitizer but also decreases the generation of reactive oxygen species(ROS),and thus reducing the effect of the photosensitizer to elicit ***-based nanomicelles,which maintain a stable micellar structure,can prevent defects of AIE molecules in photodynamic therapy(PDT)***,in this study,a mitochondria-targeted AIE nanophotosensitizer was synthesized and used as a highly potent ICD inducer for vaccine preparation and tumor prevention.

关键词： Aggregation induced emission Photodynamic therapy Immunogenic cell death Reactive oxygen species Nanophotosensitizer Mitochondria

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An open access dataset for strong-motion data(PGA,PGV,and Site V_(S30))of 2023 M6.2 Jishishan,Gansu,China earthquake

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Earthquake Science 2024年第6期37卷 584-587页

作者： jian Zhou Li Li Nan Xi kun Chen Xin Tian Chao Wang Jifeng Tian Institute of Geophysics China Earthquake AdministrationBeijing 100081China China Earthquake Network Center Beijing 100045China

*** On December 18,2023,a M6.2 earthquake struck central China with epicenter at Jishishan,Gansu(35.70°N,102.79°E).In the USGS Latest Earthquake platform,the event was identified as M_(W)5.9,35.743°N,102.827°E,labeled 37 km WNW of Linxia Chengguanzhen,*** study presents an open-access dataset comprising PGA and PGV records of the main-shock from 202accelerometers and 539 Micro-Electro-Mechanical System(MEMS)sensors within two arcdegrees of the epicenter.

关键词： China. earthquake epicenter

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Catalytic asymmetric dearomative azo-Diels–Alder reaction of 2-vinlyindoles

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Chinese Chemical Letters 2024年第4期35卷 357-362页

作者： Yu-Hang Miao Zheng-Xu Zhang Xu-Yi Huang Yuan-Zhao Hua Shi-kun Jia Xiao Xiao Min-Can Wang Li-Ping Xu Guang-jian Mei Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450052China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China Institute of Pharmaceutical Science and Technology Zhejiang University of TechnologyHangzhou 310014China

Due to the high electrophilic nature of azo-dienophiles, azo-Diels–Alder proceeds rapidly even without the need of a catalyst and is therefore regarded as the “click reaction”. This spontaneity causes strong background reaction and poses a daunting challenge to chemists for developing the catalytic asymmetric version. Reported herein is the first catalytic asymmetric dearomative azo-Diels–Alder reaction between2-vinylindoles and triazoledione. This protocol makes use of the high energy barrier of dearomatization to avert the strong background reaction of azo-Diels–Alder reaction, allowing the implementation of the projected reaction at ambient temperature. Density functional theory calculations have been performed to gain insights into the reaction mechanism and the origins of the enantioselectivity. By using this method,a variety of tetracyclic indole derivatives have been readily prepared in good to excellent yields and with excellent diastereo-and enantio–selectivities(33 examples, up to 97% yield and >99% ee, >20:1 dr).

关键词： Catalytic asymmetric dearomatization Azo-Diels–Alder reaction 2-Vinylindoles Chiral phosphoric acid Tetracyclic indole derivatives

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Changes in posterior corneal elevation after small incision lenticule extraction for different myopic diopters

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 491-498页

作者： Xiao-Tong Sun Yang Zhang Xiao-kun Mei Nan-Nan Zheng Ling-Zhi Niu Xiao-Li Qu Ai-Ping Song jian Zhuo Department of Ophthalmology the First Affiliated Hospital of Shandong First Medical UniversityShandong Provincial Qianfoshan HospitalJinan 250014Shandong ProvinceChina

●AIM:To study the changes and effect factors of posterior corneal surface after small incision lenticule extraction(SMILE)with different myopic diopters.●METHODS:Ninety eyes of 90 patients who underwent SMILE were included in this retrospective *** were allocated into three groups based on the preoperative spherical equivalent(SE):low myopia(SE≥-3.00 D),moderate myopia(-3.00 D>SE>-6.00 D)and high myopia(SE≤-6.00 D).Posterior corneal surfaces were measured by a Scheimpflug camera preoperatively and different postoperative times(1wk,1,3,6mo,and 1y).Posterior mean elevation(PME)at 25 predetermined points of 3 concentric circles(2-,4-,and 6-mm diameter)above the best fit sphere was analyzed.●RESULTS:All surgeries were completed uneventfully and no ectasia was found through the *** difference of myopia group was significant at the 2-mm ring at 1 and 3mo postoperatively(1mo:P=0.017;3mo:P=0.018).The effect of time onΔPME was statistically significant(2-mm ring:P=0.001;4-mm ring:P<0.001;6-mm ring:P<0.001).The effect of different corneal locations onΔPME was significant except 1wk postoperatively(1mo:P=0.000;3mo:P=0.000;6mo:P=0.001;1y:P=0.001).Posterior corneal stability was linearly correlated with SE,central corneal thickness,ablation depth,residual bed thickness,percent ablation depth and percent stromal bed thickness.●CONCLUSION:The posterior corneal surface changes dynamically after *** protrusion is observed on the posterior corneal surface in patients with different degrees of myopia within one year after *** has good stability,accuracy,safety and predictability.

关键词： myopia posterior corneal elevation corneal ectasia small incision lenticule extraction

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Programmable repulsive potential for tight-binding from ChenM?bius inversion theorem

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Science China(Physics,Mechanics & Astronomy) 2024年第1期 75-87页

作者： jian-Gao Li Jin-kun Tang Hong-Quan Song Gotthard Seifert Dong-Bo Zhang College of Nuclear Science and Technology Beijing Normal University Department of Physics Beijing Normal University College of Physics and Telecommunication Engineering Zhoukou Normal University Theoretische Chemie Technische Universit?t Dresden

An accurate total energy calculation is essential in materials computation. To date, many tight-binding(TB) approaches based on parameterized hopping can produce electronic structures comparable to those obtained using first-principles ***, TB approaches still have limited applicability for determining material properties derived from the total energy. That is, the predictive power of the TB total energy is impaired by an inaccurate evaluation of the repulsive energy. The complexity associated with the parametrization of TB repulsive potentials is the weak link in this evaluation. In this study, we propose a new method for obtaining the pairwise TB repulsive potential for crystalline materials by employing the Chen-M?bius inversion theorem. We show that the TB-based phonon dispersions, calculated using the resulting repulsive potential, compare well with those obtained by first-principles calculations for various systems, including covalent and ionic bulk materials and twodimensional materials. The present approach only requires the first-principles total energy and TB electronic band energy as input and does not involve any parameters. This striking feature enables us to generate repulsive potentials programmatically.

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Significantly enhanced superconductivity in monolayer FeSe films on SrTiO3（001） via metallic δ-doping

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National Science Review 2024年第3期11卷 119-127页

作者： Xiaotong Jiao Wenfeng Dong Mingxia Shi Heng Wang Cui Ding Zhongxu Wei Guanming Gong Yanan Li Yuanzhao Li Binjie Zuo jian Wang Ding Zhang Minghu Pan Lili Wang Qi-kun Xue State Key Laboratory of Low-Dimensional Quantum Physics Department of Physics Tsinghua University School of Physics&Information Technology Shaanxi Normal University Beijing Academy of Quantum Information Sciences Department of Physics Southern University of Science and Technology International Center for Quantum Materials School of Physics Peking University Department of Physics The Pennsylvania State University Collaborative Innovation Center of Quantum Matter Hefei National Laboratory

Superconductivity transition temperature（Tc） marks the inception of a macroscopic quantum phase-coherent paired state in fermionic systems. For 2D superconductivity, the paired electrons condense into a coherent superfluid state at Tc, which is usually lower than the pairing temperature, between which intrinsic physics including Berezinskii–Kosterlitz–Thouless transition and pseudogap state are hotly debated. In the case of monolayer FeSe superconducting films on SrTiO3（001）, although the pairing temperature（Tp） is revealed to be 65–83 K by using spectroscopy characterization, the measured zero-resistance temperature（Tc0） is limited to 20 K. Here, we report significantly enhanced superconductivity in monolayer FeSe films by δ-doping of Eu or Al on SrTiO3（001） surface, in which Tc0is enhanced by 12 K with a narrowed transition width ΔTc～8 K, compared with non-doped samples. Using scanning tunneling microscopy/spectroscopy measurements, we demonstrate lowered work function of the δ-doped SrTiO3（001） surface and enlarged superconducting gaps in the monolayer FeSe with improved morphology/electronic homogeneity. Our work provides a practical route to enhance 2D superconductivity by using interface engineering.

关键词： monolayer FeSe interface superconductivity δ-doping zero-resistance temperature superconductivity transition temperature

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