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Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang Li-Shuo Zheng Yu-Tao Zheng Yi-wei Dong Liping Huang Xiaoping Wang wei jiang Liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

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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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Integrating lipidomics and gut microbiota to study the anti-hyperlipidemia effect of Sargentodoxae Caulis extract

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Traditional Medicine Research 2025年第1期10卷 1-11页

作者： Xiao-Xiao Zhang Li Jia Xiu-Jun Zhan Charity Ngina qing-Rui Zhang Xiao-Ge Li Qi-Bao jiang Shi Bai Miao-Miao jiang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjin 301617China Haihe Laboratory of Modern Chinese Medicine Tianjin 301617China School of Medicine Taizhou UniversityTaizhou 318000China.

Background:Sargentodoxae Caulis(SC)is the vine stem of Sargentodoxa Cuneata(Oliv.)Rehd.&*** in ***,and it in traditional Chinese medicine has been known for promoting blood circulation and removing blood stasis as recorded in the ancient book“Illustrated Classics of Materia Medica”.It has been used effectively to treat blood stasis too in modern clinical ***,the anti-hyperlipidemia effect of SC is not fully *** paper aims at exploring the use of SC stems to improve the balance of blood lipids in the body,and its new role in treating ***:The effects of SC extract on hyperlipidemia were explored by combining lipidomics and gut ***,we explored the potential mechanism of SC in treating hyperlipidemia by pathway ***:The results showed that the stem extract of SC could restore the physiological and biochemical indices of hyperlipidemia in mice,as well as repair the morphological and structural damage to *** to the Model group,the SC extract significantly reduced the liver index,epididymal fat index,and Lee’s *** also significantly decreased serum levels of total cholesterol,triglycerides,low-density lipoprotein cholesterol,peroxisome proliferator-activated receptor gamma(PPAR-γ),D-lactate,and free fatty acids,while significantly increasing the relative content of peroxisome proliferator-activated receptor alpha(PPAR-α).These changes were statistically ***-targeted lipidomics,based on LC-MS,were utilized to investigate the lipid metabolism characteristics in serum,liver,and epididymal fat of the *** was observed that,compared to the blank group,the Model group exhibited significant changes primarily in glycerol lipids and *** treatment group also displayed alterations in these lipids.A total of 38,81,and 27 differential lipids were identified in serum,liver,and epididymal fat samples,*** these,14 common differenti

关键词： hyperlipidemia Sargentodoxae Caulis lipidomics intestinal flora

基于CodeBERT和Stacking集成学习的补丁正确性验证方法

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计算机科学 2025年第1期52卷 250-258页

作者：韩威姜淑娟周伟中国矿业大学计算机科学与技术学院江苏徐州221116 中国矿业大学矿山数字化教育部工程研究中心江苏徐州221116

近年来,自动程序修复已成为软件工程领域的重要研究课题。然而,现有的自动修复技术大多是基于补丁生成和测试的,在补丁验证环节时间成本很高。此外,由于测试套件的不完备,许多候选补丁虽然能通过测试,但实际上并不正确,从而导致补丁过... 详细信息

近年来,自动程序修复已成为软件工程领域的重要研究课题。然而,现有的自动修复技术大多是基于补丁生成和测试的,在补丁验证环节时间成本很高。此外,由于测试套件的不完备,许多候选补丁虽然能通过测试,但实际上并不正确,从而导致补丁过拟合。为提高补丁验证的效率并缓解补丁过拟合的问题,提出了一种静态的补丁验证方法。该方法首先使用大型预训练模型CodeBERT自动提取缺陷代码片段和补丁代码片段的语义特征,然后使用历史缺陷修复补丁数据训练Stacking集成学习模型,训练之后的模型可以对新的缺陷修复补丁进行有效验证。在Defects4J缺陷数据集相关的1 000个补丁数据上对所提方法的验证能力进行评估。实验结果表明,该方法可以有效地验证补丁的正确性,从而提高补丁验证的效率。

关键词：自动程序修复补丁验证预训练模型集成学习 Defects4J缺陷数据集

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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou wei-Jin jiang Ji Yu Mao-Jun Yao Yun-Tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

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南丰蜜橘叶片养分状况分析

江西农业大学学报 2019年第6期41卷 1072-1078页

作者：魏清江杨莉刘德春胡威黄国安蔡伯龄吴德志刘勇江西农业大学农学院江西南昌330045 江西省南丰蜜橘产业局江西南丰344500

为了解南丰蜜橘树体养分丰缺现状,对江西省南丰县5个乡镇的138个果园叶片矿质元素含量进行了测定。结果表明不同乡镇南丰蜜橘叶片N以偏低和适量为主,但也存在超标(偏高或过量)现象;叶片P和K以适量为主,同时偏低比例也较高。中量元素Ca... 详细信息

为了解南丰蜜橘树体养分丰缺现状,对江西省南丰县5个乡镇的138个果园叶片矿质元素含量进行了测定。结果表明不同乡镇南丰蜜橘叶片N以偏低和适量为主,但也存在超标(偏高或过量)现象;叶片P和K以适量为主,同时偏低比例也较高。中量元素Ca和Mg均不足(缺乏或偏低):其中不同乡镇Ca含量偏低的比例高达90.00%~100%;Mg以缺乏和偏低为主,所占比例为76.67%~96.78%。南丰蜜橘叶片Fe以适量和偏高为主,而Mn含量偏高,占比为76.67%~90.32%。叶片Cu均以适量为主,同时也存在偏低现象。叶片Zn含量以不足为主,不同乡镇的比例为72.00%~96.67%。相关分析显示,南丰蜜橘叶片Mg与P,K与Ca之间存在极显著负相关,但其余大部分元素之间呈正相关。综上所述,南丰蜜橘树体养分不均衡,在生产上需重视Ca、Mg和Zn肥施用,根据实际情况适量补充N、P、K和Cu养分,同时减少树体Fe和Mn元素的摄入量。

关键词：南丰蜜橘叶片矿质元素相关分析

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Homologous CoS2 interface with directed electron transfer and strong chloridion repulsion for efficient seawater oxidation

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Science China Chemistry 2025年

作者： Yuan Tian jiang-Bo Chen Jie Ying Ge Tian Yu-Xuan Xiao Yi Lu Si-Ming Wu wei Geng Ling Shen Xiao-Yu Yang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and School of Materials Science and Engineering and Shenzhen Research Institute & Laoshan Laboratory Wuhan University of Technology School of Chemical Engineering and Technology Sun Yat-Sen University National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu Laboratory

Seawater electrolysis is a highly promising method to produce high energy density hydrogen,especially in dry areas that have scarce freshwater ***,application of seawater electrolysis is confronted by two major problems associated with catalysts employed for the anodic oxygen evolution reaction （OER） including the competitive hypochlorite evolution reaction（HCER） and strong chloridion （Cl–） triggered *** studies aimed at overcoming these problems,a facile method has been developed to synthesize a homologous CoS2heterojunction as an OER *** to a difference in work functions at the interface and increased electron density,this material has directed electron transfer and strong chloridion repulsion properties,*** have shown that CoS2achieves low overpotentials of 289 and 322 mV at 10 mA cm-2current density in respective alkaline （1 M KOH） and alkaline simulated seawater ***,the outstanding stability of CoS2is reflected in a negligible decline in activity during promotion of the OER for 100 *** of density functional theory calculations reveal that the homologous CoS2heterojunction promotes directed electron transport for optimizing adsorption/desorption of reactive species and heightens the Cl-adsorption energy for strongly repulsing Cl-,phenomena that enhance OER performance in alkaline simulated seawater.

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Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-Ang Nan qing Li Xiufang Li Zi-Xiu Lu Linzhe Lü Jin Liu Luyao Liu Wenjing Wang wei Wang Daqiang Yuan You-Gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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南丰蜜橘化渣性评价及不同结果习性果实的品质比较

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中国农业科学 2014年第6期47卷 1162-1170页

作者：魏清江汪妙秋曾知富杨成泉彭抒昂刘永忠华中农业大学园艺林学学院/园艺植物生物学教育部重点实验室江西省抚州市南丰柑橘研究所

【目的】建立南丰蜜橘化渣性品质的量化指标,比较不同结果习性果实的品质差异,为制定改善南丰蜜橘化渣性品质的栽培措施提供依据。【方法】以南丰蜜橘为材料,用感官品尝的方法区分果实的化渣性,并测定化渣性不同果实的囊衣厚度和囊瓣剪... 详细信息

【目的】建立南丰蜜橘化渣性品质的量化指标,比较不同结果习性果实的品质差异,为制定改善南丰蜜橘化渣性品质的栽培措施提供依据。【方法】以南丰蜜橘为材料,用感官品尝的方法区分果实的化渣性,并测定化渣性不同果实的囊衣厚度和囊瓣剪切力、硬度、咀嚼度等化渣性品质指标,分析果实化渣性和这些指标的相关性。进一步测定不同结果习性果实的化渣性品质与常规品质(维生素C、可溶性固形物和可滴定酸)的差异。【结果】囊瓣剪切力和囊衣厚度能够客观反映果实的化渣程度,利用这两个指标可对果实化渣性进行量化;根据品尝试验、囊衣厚度和囊瓣剪切力的结果范围,可将南丰蜜橘果实的化渣性分为3个等级:"化渣"果实的囊瓣剪切力为1.15—1.64 kg,囊衣中间处厚度为0.09—0.12 cm;"较化渣"果实的囊瓣剪切力为1.64—2.63 kg,囊衣中间处厚度为0.12—0.14 cm;"不化渣"果实的囊瓣剪切力为2.63—5.70 kg,囊衣中间处厚度为0.14—0.17 cm;比较不同结果习性果实的品质表明:大果的化渣性优于中果和小果,而中果的常规品质优于小果和大果;短枝果实的化渣性优于长枝果实的,但两者的常规品质没有差异;高负载枝果实化渣性显著优于低负载枝果实,但不同负载量枝条上果实的常规品质没有差异;外膛果的常规品质和化渣性均优于内膛果实;树冠中层果实的化渣性较好,且上层和中层果实的常规品质优于下层果实。【结论】化渣性是南丰蜜橘重要的品质指标,可用囊瓣剪切力及囊衣厚度进行量化评价;不同结果习性的果实品质有差异,化渣性品质与常规品质没有相关性,但化渣性品质好的果实,其常规品质也较好。

关键词：南丰蜜橘化渣性囊瓣剪切力囊衣厚度结果习性