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Visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)

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Chinese Chemical Letters 2024年第7期35卷 281-284页

作者： Tian-Yu Gao Xiao-Yan Mo Shu-Rong Zhang Yuan-Xu Jiang Shu-Ping Luo Jian-heng ye Da-Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Herein, we report the first visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)to synthesize hydroxy acid derivatives. A variety of valuable β-, γ-, δ-, ε–hydroxy acid derivatives are obtained in moderate to high yields under mild conditions. This protocol shows noteworthy functionalgroup compatibility, high chemo-and regioselectivities under transition-metal-free conditions with an inexpensive organo-dye as photosensitizer. Mechanistic studies indicate that the benzylic carbanion is generated as an intermediate via the sequential single electron transfer(SSET) process.

关键词： Carbon dioxide Epoxides Visible-light photoredox catalysis Hydroxy acid Sequential single electron transfer

Photocatalytic dicarboxylation of strained C-C bonds with CO_(2) via consecutive visible-light-induced electron transfer

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Chinese Chemical Letters 2024年第6期35卷 268-273页

作者： Yi Liu Zhe-Hao Wang Guan-Hua Xue Lin Chen Li-Hua Yuan Yi-Wen Li Da-Gang Yu Jian-heng ye Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Dicarboxylic acids have a wide range of applications in the polymer industry to construct valuable *** has recently emerged as an efficient and sustainable strategy to generate dicarboxylic ***,photocatalytic dicarboxylation with CO_(2) is mainly limited to unsaturated bonds,and the dicarboxylation of C-C single bonds still remains a ***,we report a photocatalytic dicarboxylation of C-C single bonds in strained rings with CO_(2) units via consecutive photo-induced electron transfer(ConPET).It is also the first photocatalytic reductive ring-opening reaction of ***,this transition-metal-free protocol exhibits good functional group tolerance,broad substrate scope,facile scalability,and easy product ***,diacids can easily be derivatized to mainchain liquid crystalline polyesters.

关键词： Consecutive photo-induced electron transfer Visible-light catalysis Dicarboxylation Carbon dioxide Cyclopropanes

重金属污染水体背景下的底质反射率光谱特征及其对离水反射率贡献影响分析

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光谱学与光谱分析 2024年第1期44卷 111-117页

作者：梁业恒邓孺孺梁钰婕刘永明吴仪袁宇恒艾先俊中山大学地理科学与规划学院广东厂州510006 广东省水环境遥感监测工程技术研究中心广东广州510006 中国科学院南海海洋研究所热带海洋环境国家重点实验室广东广州510301 香港中文大学地理与资源管理系中国香港990775 北京师范大学地理科学学部北京100875 广州市城市规划勘测设计研究院花都分院广东广州510060

水体重金属遥感反演是水环境遥感领域中的难题,目前仍有相当多的基础性问题有待解决,而浅水区底质对离水反射率贡献规律是将来遥感反演模型精度其中一个重要影响因素,尤其在重金属污染这种特殊的背景下,揭示其贡献规律对提升水体重金属... 详细信息

水体重金属遥感反演是水环境遥感领域中的难题,目前仍有相当多的基础性问题有待解决,而浅水区底质对离水反射率贡献规律是将来遥感反演模型精度其中一个重要影响因素,尤其在重金属污染这种特殊的背景下,揭示其贡献规律对提升水体重金属遥感模型精度有重要作用,测量结果对研究重金属尾矿底泥的反射率光谱特征以及区分常见水底底质有参考意义。首先利用光谱仪测量获得广东大宝山尾矿底质反射率,发现其在波长755、 1 280、 1 620和2 200 nm存在反射峰,有明显光谱特征,并与河床常见的粗沙、淤泥和石头三类底质反射率进行了对比分析,结果表明:一方面,粗沙和淤泥反射率呈一缓慢上升的曲线,与存在多个特征反射峰的矿区底泥有明显区别;另一方面,石头反射率则在波长范围550~650 nm出现一个宽而扁平的反射峰后随即在波长675 nm处出现波谷然后增大至波长750 nm后趋于平缓,其特征波长与矿区底泥均不一样。上述特征波长可作为重金属污染背景下底泥光谱的重要区分波段。测量水深为1 cm、 10 cm和深水区的离水反射率,结合水质遥感模型计算出1 cm水深情况下底质反射光、水体散射光,并将其对离水反射率贡献进行讨论。离水反射率测量结果表明,底质对浅水区影响极大,随着水深变浅,离水反射率总体不断被抬升。而水底反射光和水体散射光对离水反射率贡献规律则以波长515 nm为分界线,向短波方向以水体散射光贡献为主,向长波方向则以水底反射光为主,贡献量由底质反射能力和水体散射能力共同决定。对考虑了底质反射光后的遥感模型精度进行评价,模型计算得到波长范围350~950 nm内的离水反射率与野外测量值对比结果,二者具有显著的线性相关(R^(2)=0.964 2),相对误差在波长范围560~830 nm低于10%,甚者可低于5%,模型总体模拟精度较好,远比在不考虑底质影响时精度高,模型满足将来水中重金属遥感反演要求。研究结果对今后水体重金属遥感反演时处理底质影响提供了重要的参考数据和理论依据,有助推动该领域进一步发展。

关键词：水体重金属遥感重金属矿区底质反射率光谱特征分析模型精度评价

前提性反思:中国式现代化研究无法回避的问题

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内蒙古社会科学 2024年第4期45卷 17-23页

作者：贾丽民宋叶恒天津师范大学马克思主义学院天津300387

何以进一步推进和深化中国式现代化研究,是当今学术界无法回避的重大课题。对此,要想做出有力回应、在已有研究成果的基础上实现进一步突破,就需要把中国式现代化拉入到整个人类社会现代化发展的大坐标系中,对其进行整体性审视和前提性... 详细信息

何以进一步推进和深化中国式现代化研究,是当今学术界无法回避的重大课题。对此,要想做出有力回应、在已有研究成果的基础上实现进一步突破,就需要把中国式现代化拉入到整个人类社会现代化发展的大坐标系中,对其进行整体性审视和前提性反思,而不是做简单的重复性阐释。从整个人类社会现代化发展的历史进程、具体呈现、未来趋势看,在“一元”与“多元”、“本土”与“外来”、“进行时”与“完成时”的辩证关系中思考和把握中国式现代化,是对中国式现代化研究进行前提性反思的关键所在。惟其如此,才能以客观、辩证、历史的立场研析中国式现代化问题,将中国式现代化研究向纵深推进。

关键词：中国式现代化前提性反思辩证关系

WAVE MAKING COMPUTATION IN TIME DOMAIN FOR MULTI-HULL SHIPS

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Journal of Hydrodynamics 2006年第2期18卷 225-230页

作者： LI Guo-an ye heng-kui School of Traffic Science and Engineering Huazhong University of Science and Technology Wuhan 430074China

A method Green function satisfying of three-dimensional time domain linear conditions at free surface and body surface boundary was employed to analyze the wave resistance and wave profile of a displacement multi-hull ship. The wave profile induced by a moving time domain point source was compared with those by a Havelock source, and satisfactory results were obtained. The panel method based on the time domain source distribution on the ship mean wetted hull surface was used to perform the wave making com- putations tbr mono-hull ships, catamaran and trimaran. Reasonable results were also obtained. Using the numerical method the wave profile simulations of multi-hull ships for a given Froude number were conducted.

关键词： time domain Green function ship wave making mono-hull catamaran trimaran

An Examination of Some Factory Physics Principles

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Journal of the Operations Research Society of China 2016年第2期4卷 131-145页

作者： Hong Chen heng-Qing ye Shanghai Advanced Institute of Finance Shanghai Jiaotong UniversityShanghai 200240China Faculty of Business Hong Kong Polytechnic UniversityHong KongChina

In this paper,we examine some principles in managing manufacturing sys*** principles are concerned with the variability,the utilization,the rework,the lead time,and the constant work-in-process *** these principles are developed through analyzing some simpler disconnected flow line manufacturing systems,we examine whether they can have broad *** some of these principles,we provide sufficient conditions,while for others,we provide counterex*** analysis suggests that we should be very cautious about these laws when applied to non-Markov and non-tandem systems.

关键词： Factory physics Manufacturing system Variability Utilization Rework Constant work-in-process Lead time

6082铝合金冷塑性流变行为及数值模拟研究

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塑性工程学报 2024年第6期31卷 141-148页

作者：张志强龚红英周志伟叶恒昌赵江波上海工程技术大学材料工程学院上海201620

进行了常温单向拉伸试验、硬度测试和金相试验,研究了6082铝合金冷塑性变形行为。通过对拉伸后试样的断后伸长率和断面收缩率进行研究发现,随着拉伸速率的增大,两者先增大后减小。通过扫描电镜(SEM)分析,发现6082铝合金的断口形貌呈现... 详细信息

进行了常温单向拉伸试验、硬度测试和金相试验,研究了6082铝合金冷塑性变形行为。通过对拉伸后试样的断后伸长率和断面收缩率进行研究发现,随着拉伸速率的增大,两者先增大后减小。通过扫描电镜(SEM)分析,发现6082铝合金的断口形貌呈现出韧窝-脆面混合断裂的模式,并且在高速拉伸时出现大量破碎的硬脆相。对6082铝合金拉伸试验得到的数据进行分析并建立了优化本构方程,结合有限元数值模拟试验分析,将所建立的优化后的材料本构模型输入有限元软件中进行模拟验证,两者相对误差为1.33%,说明建立的模型可以准确描述6082材料在冷塑性变形状态下的硬化行为。

关键词： 6082铝合金本构模型冷成形有限元单向拉伸

广西喀斯特峰丛洼地造林对土壤有机碳、氮及其组分的影响

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农业现代化研究 2024年第2期45卷 316-325页

作者：周业恒肖孔操夏世斌何寻阳李德军武汉理工大学资源与环境工程学院湖北武汉430070 中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室湖南长沙410125 中国科学院环江喀斯特生态系统观测研究站广西环江547100

植树造林是促进退化喀斯特生态系统植被恢复同时提升生态碳汇的重要措施。目前,关于喀斯特峰丛洼地区造林对土壤碳氮组分及其生物化学稳定性的影响认识还很不足。本研究在广西喀斯特峰丛洼地区配对采集了玉米地及其邻近人工林表层(0~15 ... 详细信息

植树造林是促进退化喀斯特生态系统植被恢复同时提升生态碳汇的重要措施。目前,关于喀斯特峰丛洼地区造林对土壤碳氮组分及其生物化学稳定性的影响认识还很不足。本研究在广西喀斯特峰丛洼地区配对采集了玉米地及其邻近人工林表层(0~15 cm)和亚表层(30~45 cm)土壤样品各14组,采用酸水解法对土壤碳、氮组分(活性碳、氮组分I,活性碳、氮组分II和惰性碳、氮组分)进行了测定。研究表明,农田退耕造林20年后,表层和亚表层土壤总有机碳、全氮、活性碳组分、惰性碳组分、活性氮组分与惰性氮组分含量均有不同程度的增加。与农田相比,人工林土壤碳库活度(活性碳库/惰性碳库)整体降低,碳库稳定性(惰性碳占土壤总有机碳的比例)显著提高。逐步回归分析表明,根系生物量、碳酸钙和交换性钙离子是造林后土壤有机碳、氮及其组分含量增加的主控因子。

关键词：造林土壤有机碳组分稳定性喀斯特峰丛洼地

Co-delivery of Andrographolide and Notch1-targeted siRNA to Macrophages with Polymer-based Nanocarrier for Enhanced Anti-inflammation

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Chinese Journal of Polymer Science 2018年第12期36卷 1312-1320页

作者： Teng Wu Min Tan heng-ye Gong Yong Wang Xin-Tao shuai PCFM Lab of Ministry of Education School of Materials Science and Engineering Sun Yat-Sen University Guangzhou 510275 China Center of Biomedical Engineering Zhongshan School of Medicine Sun Yat-sen University Guangzhou 510080 China

Chronic inflammatory responses induced by macrophages play a pivotal role in the progression of atherosclerosis. In the present study, a multifunctional nanocarrier based on poly（ethylene glycol）-block-poly（L-aspartic acid） grafted with diethylenetriamine, lysine and cholic acid （PEG-PAsp（DETA）-Lys-CA2） polymer was synthesized for co-delivery of andrographolide and siRNA targeting Notchl gene to alleviate the inflammatory response in macrophages. The nanocarrier exerted low cytotoxicity as well as high performance in drug/siRNA co-delivery. In vitro studies demonstrated the co-delivery of andrographolide and Notchl siRNA not only significantly inhibited lipopolysaccharide （LPS）-activated interleukin-6 （IL-6） and monocytes chemotactic protein 1 （MCP-1） expression as well as blocked nuclear factor-rd3 （NF-rd3） signal activation, but also interfered the Notchl gene expression and increased anti-inflammatory cytokines such as interleukin-10 （IL-10） and arginase-1 expression obviously in macrophages. These results suggested that the combination therapy based on Notchl siRNA and andrographolide co-delivered nanocarrier, i.e. suppressing the expression of proinflammatory cytokines while simultaneously increasing anti-inflammatory factors expression, be a feasible strategy for atherosclerosis treatment.

关键词： Macrophages Anti-inflamatory Andrographolide Notchl siRNA