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Revisit the Gibbs-Thomson Equation Fitting of Poly(butylene succinate) Based on Oligomer Extended-Chain Crystals

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CHINESE JOURNAL OF POLYMER SCIENCE 2025年第2期43卷 392-398页

作者： Li, Na tian, yu-Pei Wu, tian-yu Zhou, Qiong Ye, Hai-Mu China Univ Petr Coll New Energy & Mat Beijing 102249 Peoples R China

The equilibrium melting point (Tm0) is a crucial thermodynamic parameter for characterizing the crystallization and melting behavior of semi-crystalline polymers. However, the direct measurement of Tm0 poses a significant challenge because of the difficulty in physically fabricating fully-extended chain crystals of high-molecular-weight polymers. Therefore, various extrapolation equations for Tm0 have been proposed that utilize the thermal properties of ordinary folded-chain lamellae. Among these, the Gibbs-Thomson equation is one of the most commonly employed for modeling. Despite its widespread use, there are notable variations in the Tm0 values obtained by different research groups, even when based on similar samples. This raises questions about the validity and accuracy of using the Gibbs-Thomson equation to linearly extrapolate Tm0. In this study, we prepared a series of oligomer extended-chain crystals (ECCs) of poly(butylene succinate) (PBS) and used their properties for Gibbs-Thomson fitting. The results reveal a perfect linear relationship, with an extrapolated Tm0 value of 136.08 degrees C. The basal surface free energy of the oligomer ECCs was calculated as 0.084 J/m2, which is approximately twice that of folded-chain lamellae. This difference is attributed to the aggregation of highly mobile free tails on the crystal surface. The two structural features of oligomer ECCs-large thickness and fixed surface-better fulfill the conditions for applying the Gibbs-Thomson equation, ensuring its validity and accuracy. Therefore, we believe that the Gibbs-Thomson fit can produce reliable results when sufficient high-quality data are used.

关键词： Equilibrium melting point Extended-chain crystal Gibbs-Thomson equation Inclusion complex

Hyperbranched Poly(α-aminonitrile)s Constructed via Catalyst-Free Multicomponent Polymerization of Trialdehydes, Diamines and Trimethylsilyl Cyanide

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CHINESE JOURNAL OF POLYMER SCIENCE 2025年第2期43卷 341-349页

作者： Cheng, tian-yu Ding, Jian-Qing Tong, yu-Xin Fang, Jun-Guo Wang, Jia Anhui Polytech Univ Sch Chem & Environm Engn Wuhu 241000 Peoples R China Songshan Lake Mat Lab Dongguan 523808 Peoples R China

Functional hyperbranched polymers, as an important class of materials, are widely applied in diverse areas. Therefore, the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance. In this work, trialdehydes, diamines, and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions, producing hyperbranched poly(alpha-aminonitrile)s with high molecular weights (Mw up to 4.87x104) in good yields (up to 85%). The hyperbranched poly(alpha-aminonitrile)s have good solubility in commonly used organic solvents, high thermal stability as well as morphological stability. Furthermore, due to the numerous aldehyde groups in their branched chains, these hb-poly(alpha-aminonitrile)s can undergo one-pot, two-step, four-component post-polymerization with high efficiency. This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes, amines and trimethylsilyl cyanide, but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.

关键词： Catalyst-free Multicomponent polymerization Hyperbranched polymer Post-polymerization

An analytic proof of multivariate Polya-Carlson theorem

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Acta Mathematica Sinica,English Series 2025年

作者： tian Long yu School of Mathematical Sciences Peking University

Polya-Carlson theorem asserts that if a power series with integer coefficients and convergence radius 1 can be extended holomorphically out of the unit disc, it must represent a rational function. In this note, we give a generalization of this result to multivariate case and give an application to rationality theorem about D-finite power series.

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Adaptive VDI Session Placement via User Logoff Prediction

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Machine Intelligence Research 2025年第1期22卷 189-200页

作者： Wenping Fan Puhui Meng yu tian Min-Ling Zhang Yao Zhang School of Computer Science and Engineering Southeast UniversityNanjing210096China VMware Information Technology(China)Limited Beijing100190China Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of EducationNanjing210096China

After the global pandemic,DaaS(desktop as a service)has become the first choice of many companies’remote working *** the desktops are usually deployed in the public cloud when using DaaS,customers are more cost-sensitive which boosts the requirement of proactive power *** researches in this area focus on virtual desktop infrastructure(VDI)session logon behavior modeling,but for the remote desktop service host(RDSH)-shared desktop pools,logoff optimization is also *** systems place sessions by round-robin or in a pre-defined order without considering their logoff ***,these approaches usually suffer from the situation that few left sessions prevent RDSH servers from being powered-off which introduces cost *** this paper,we propose session placement via adaptive user logoff prediction(SODA),an innovative compound model towards proactive RDSH session ***,an ensemble machine learning model that can predict session logoff time is combined with a statistical session placement bucket model to place RDSH sessions with similar logoff time in a more centralized manner on RDSH ***,the infrastructure cost-saving can be improved by reducing the resource waste introduced by those RDSH hosts with very few hanging sessions left for a long *** on real RDSH pool data demonstrate the effectiveness of the proposed proactive session placement approach against existing static placement techniques.

关键词： Virtual desktop infrastructure(VDI)resource management remote desktop service logoff prediction adaptive modeling session placement

A dual drug-loaded tumor vasculature-targeting liposome for tumor vasculature disruption and hypoxia-enhanced chemotherapy

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Chinese Chemical Letters 2025年第1期36卷 397-402页

作者： Cheng-Zhe Gao Hao-Ran Jia tian-yu Wang Xiao-yu Zhu Xiaofeng Han Fu-Gen Wu State Key Laboratory of Digital Medical Engineering Jiangsu Key Laboratory for Biomaterials and DevicesSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 211189China

Vascular disrupting agents(VDAs)can destroy tumor vasculature and lead to tumor ischemia and hypoxia,resulting in tumor ***,VDAs are easy to induce the upregulation of genes that are associated with cancer cell drug resistance and angiogenesis in tumor ***-activated chemotherapy will be an ideal supplement to VDAs therapy since it can help to fully utilize the ischemia and hypoxia induced by VDAs to realize a synergistic antitumor therapeutic ***,we design a liposome whose surface is modified with a tumor-homing peptide Cys-Arg-Glu-Lys-Ala(CREKA,which can specifically target tumor vessels and stroma)and whose aqueous cavity and lipid bilayer are loaded by a hypoxia-activatable drug banoxantrone dihydrochloride(AQ4N)and a VDA combretastatin A4(CA4),***4 can selectively target vascular endothelial cells and destroy the tumor blood vessels,which will cause the rapid inhibition of blood flow in tumor and enhance the hypoxia in the tumor *** a consequence,AQ4N can exert its boosted cytotoxicity under the enhanced hypoxic *** as-prepared liposome with a uniform particle size exhibits good stability and high cancer cell killing efficacy in *** addition,in vivo experiments confirm the excellent tumortargeting/accumulation,tumor vasculature-damaging,and tumor inhibition effects of the *** work develops a liposomal which can achieve safe and effective tumor suppression without external stimulus excitation by only single injection,and is expected to benefit the future development of effective antitumor liposomal drugs.

关键词： Tumor-homing peptide Liposome Vascular disrupting agents Chemotherapy Hypoxia-activated

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Modular access toπ-conjugated planar chiral diradicaloids using redox-active pillar[5]arenes

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Science China Chemistry 2025年

作者： yuting Xue Yi Zeng Yafei Shi yu tian Cuiping Sun Niu Zhang Xiaoyan Zheng Pangkuan Chen Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials Key Laboratory of Cluster Science of the Ministry of Education Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering of the Ministry of Industry and Information Technology School of Chemistry and Chemical Engineering Beijing Institute of Technology Analysis & Testing Centre Beijing Institute of Technology

Open-shell chiral diradicals that feature both the unique chiroptical properties and tunable spin states have kindled numerous interests in organic synthesis and material *** present a new class of such model systems based on theπ-extended planar chiral pillar[5]arene derivatives P5Flu and P5Cz,where the pillar[5]arene-based chiral scaffolds are coupled with sterically encumbered fluorenyl and carbazolyl moieties as highly luminescent redox-active emitters,*** molecules in neutral states can readily undergo chemical oxidations leading toπ-conjugated chiral diradicals of the dehydrogenated P5Flu2·and a positively charged dication P5Cz2+2·.Characterization of the resulting Müller’s open-shell species by variable-temperature electron spin resonance （VT-ESR）,UV-vis-NIR absorption,VT-NMR and by computational studies revealed a singlet (ΔES-T=?1.63 kcal mol-1) and a nearly degenerate singlet-triplet ground state (ΔES-T=0.05 kcal mol-1,with a diradical character index y0=0.89) for P5Cz2+2·and P5Flu2·,*** particularly show in this work a new journey for pillar[5]arenes from the conventionally available closed-shell structures to different open-shell spin states with potential applications in chirospintronics and NIR-active chiroptoelectronic materials.

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论新质生产力引领体育产业高质量发展

体育文化导刊 2025年第1期 83-88,96页

作者：尔雨田天津天狮学院体育部天津301700

运用文献资料法,探讨新质生产力引领体育产业高质量发展的内涵、机制,并提出发展路径。新质生产力引领体育产业高质量发展的内涵:借助新技术、新业态、新机制,在更大范围和更深层次满足人们对体育的发展型、享受型需要。机制:技术创新... 详细信息

运用文献资料法,探讨新质生产力引领体育产业高质量发展的内涵、机制,并提出发展路径。新质生产力引领体育产业高质量发展的内涵:借助新技术、新业态、新机制,在更大范围和更深层次满足人们对体育的发展型、享受型需要。机制:技术创新驱动效率变革,业态创新驱动市场变革,机制创新驱动社会变革。发展路径:加快技术落地,推动体育产业的效率提升;加强产业融合,推动体育产业的业态升级;加大政府支持,推动体育产业的治理升档。

关键词：体育经济新质生产力体育产业高质量发展

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Colorectal cancer early screening:Dilemmas and solutions

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World Journal of Gastroenterology 2025年第9期31卷 154-160页

作者： Di Wu Qi-Ying Song Bai-Shu Dai Jie Li Xin-Xin Wang Jia-yu Liu tian-yu Xie Department of General Surgery First Medical Centre of Chinese PLA General HospitalBeijing 100853China Department of Neurosurgery First Medical Centre of Chinese PLA General HospitalBeijing 100853China

Colorectal cancer(CRC)is a prevalent malignancy worldwide,posing a significant public health *** evidence has confirmed that timely early screening facilitates the detection of incipient CRC,thereby enhancing patient ***,non-participation of asymptomatic individuals in screening programs hampers early diagnosis and may adversely affect long-term outcomes for CRC *** this letter,we provide a comprehensive overview of the current status of early screening practices,while also thoroughly examine the dilemmas and potential solutions associated with early screening for *** response to these issues,we proffer a set of recommendations directed at governmental authorities and the general public,which focus on augmenting financial investment,establishing standardized screening protocols,advancing technological capabilities,and bolstering public awareness *** importance of collaborative efforts from various stakeholders cannot be overstated in the quest to enhance early detection rates and alleviate the societal burden of CRC.

关键词： Colorectal cancer Early screening Asymptomatic candidates Dilemmas Solutions

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-Bo Li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang tian-yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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