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Emerging progress: photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： ze-Le Chen qiang-qiang Li Armido Studer Jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry & Chemical Engineering Anhui University Organisch-Chemisches Institut Universitat Münster

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles, nucleophiles, diradicals, and radical acceptors in diverse transformations. In recent years, notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions. Various nitroso compounds like nitrosoarenes, acyloxy nitroso compounds, N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access. In this review, we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds, with particular emphasis on their role as bifunctional reagents and acceptors of radicals, carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 246-257页

作者： ZHANG Jian NIE Wei huang Jin ZHU Ke LIU Ruxia ZHANG Ruizhi LUO Guoqiang SHEN qiang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

Efficient photocatalytic H2 evolution over tubular mesoporous carbon nitride with N-vacancy by microwave-assisted synthesis

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Science China Chemistry 2025年

作者： Yuanlong Pan qiang Zhang Guangzheng huang Yannan Luo Honglin Gao School of Materials and Energy National Center for International Research on Photoelectric and Energy MaterialsYunnan University

Modifying the microstructure of photocatalysts while simultaneously introducing vacancies has shown significant potential in enhancing their performance for hydrogen production. Herein, a novel tubular mesoporous carbon nitride（TMCN） with nitrogen vacancies was fabricated using a microwave-assisted synthesis strategy, employing melamine-cyanuric acid supramolecular（MC-S） as the precursor. The optimized TMCN exhibited an outstanding H2production rate, approximately 29 times higher than that of pristine g-C3N4. The N-vacancies serve as sites for reactant adsorption and activation, leading to enhanced delocalization of HOMO-LUMO. Furthermore, the porous structures of TMCN facilitate the reactant diffusion, while its tubular architectures promote the oriented transfer of charge carriers. Crucially, the markedly improved photocatalytic performance of TMCN can be predominantly attributed to the synergistic effects arising from its superior structure and N-vacancy defects. This work opens new possibilities for the simultaneous formation of surface defect states as photocatalytic reaction sites and distinctive structures conducive to charge carrier transport.

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Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-qiang Jiao Ming Li Xi Chen Mei-ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei Li Xue-Yuan Liu Yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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电针推拿配合中药外用对篮球运动员膝关节损伤微量元素变化的影响

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河北中医药学报 2009年第3期24卷 39-40页

作者：黄茂黄泽强潘丽敏河北体育学院石家庄050041 河北省石家庄外国语学校河北省中医院 050011

篮球运动员中膝关节损伤较为常见.笔者采用电针推拿配合威灵通络方外敷对部分膝关节损伤患者进行治疗,观察治疗前后血钙、铁、锌、硒等指标的变化.现报道如下:

关键词：电针推拿威灵通络方外敷运动损伤膝关节损伤微量元素

基于国产众核处理器的深度神经网络算子加速库优化

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计算机科学 2022年第5期49卷 355-362页

作者：高捷刘沙黄则强郑天宇刘鑫漆锋滨信息工程大学网络空间安全学院郑州450000 江南计算技术研究所江苏无锡214083 山东大学软件学院济南250101

基于不同硬件设备的算子加速库已经成为深度学习框架不可或缺的一部分,能够为大规模训练或者推理任务提供数倍的性能加速。当前的主流算子库都是基于GPU架构开发的,与其他异构设计并不兼容;SWDNN算子库是基于申威26010开发的,无法充分... 详细信息

基于不同硬件设备的算子加速库已经成为深度学习框架不可或缺的一部分,能够为大规模训练或者推理任务提供数倍的性能加速。当前的主流算子库都是基于GPU架构开发的,与其他异构设计并不兼容;SWDNN算子库是基于申威26010开发的,无法充分发挥升级后的申威26010 pro处理器的性能,也不能满足当前GPT-3等大型神经网络模型对大容量内存和高访存带宽的需求。文中面向申威26010 pro处理器体系结构的特点和大型神经网络模型的训练需求,提出了基于多核组的三级并行和神经网络算子任务调度方案,在满足大型模型训练内存需求的同时,提高了并行效率和整体计算性能;提出了三级异步流水机制和计算访存重叠的访存优化方法,显著缓解了神经网络算子的访存性能瓶颈。基于以上方法,文中构建了基于申威26010 pro处理器的SWTensor多核组算子加速库,在自然语言处理模型GPT-2上进行了实验,结果表明,其典型计算密集型算子和访存密集型算子在单精度浮点计算性能和访存带宽上分别达到了理论峰值的90.4%和88.7%。

关键词：深度神经网络算子加速库负载均衡异步流水双缓冲

12种广西地区茶叶的水提物活性成分测定及其抗氧化活性研究

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食品研究与开发 2021年第17期42卷 19-24页

作者：余启明张金华黄泽强张竞荣蔡锦源韦坤华桂林医学院公共卫生学院广西桂林541004 柳州工学院食品与化学工程学院广西柳州545616 广西药用植物园广西药用资源保护与遗传改良重点实验室广西南宁530023

对12种广西地区茶叶的水提取物活性成分及其抗氧化活性进行测定并比较分析。采用热水浴提取法制备茶叶水提物,测定水提物中的总黄酮、总多酚、总糖、儿茶素和表儿茶素含量,通过DPPH自由基、ABTS^(+)自由基的清除率和铁离子还原能力评价... 详细信息

对12种广西地区茶叶的水提取物活性成分及其抗氧化活性进行测定并比较分析。采用热水浴提取法制备茶叶水提物,测定水提物中的总黄酮、总多酚、总糖、儿茶素和表儿茶素含量,通过DPPH自由基、ABTS^(+)自由基的清除率和铁离子还原能力评价茶叶水提物的体外抗氧化活性,并对茶叶水提物的活性成分和抗氧化活性之间的相关性进行比较分析。绿茶和白茶的总多酚含量相对较高,其中三江春总多酚含量最高;红茶的总黄酮含量高于绿茶和白茶,其中梅红的总黄酮含量最高;绿茶总糖的含量相对较高,其中最高的为小叶种香茶。绿茶中三江早春侗坡仙茗和昭平乌牛早的儿茶素含量显著高于其它样品,红茶除三江梅红外其余样品均未检出,绿茶和白茶的表儿茶素较红茶高。绿茶和白茶对DPPH自由基、ABTS^(+)自由基的清除率和铁离子还原能力均较红茶高。总多酚、总糖和表儿茶素与体外抗氧化活性呈正相关,且相关性较高。而总黄酮和儿茶素与体外抗氧化活性的相关性较差,并呈现负相关。综合表明广西地区12种茶叶中,绿茶中总多酚和儿茶素、表儿茶素含量相对较高,且抗氧化活性较好;红茶中总黄酮含量较高,但总多酚、儿茶素含量、抗氧化活性均低于绿茶和白茶。

关键词：茶叶总多酚儿茶素表儿茶素抗氧化活性

The universal characteristic water content of aqueous solutions

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Chinese Physics B 2019年第6期28卷 16-19页

作者： Xiao huang ze-Xian Cao qiang Wang Institute of Physics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

Raman measurements at room temperature reveal a characteristic concentration for a series of aqueous solutions of electrolytes, through which O–H stretching vibration of H2 O or dilute HDO obviously changes their concentration dependence. This characteristic concentration is very consistent with another, through which the solutions undergo an abrupt change in their glass-forming ability. Interestingly, the molar ratio of water to solute at these two consistent concentration points is almost solute-type independent and about twice the hydration number of solutes. We suggest that just when the concentration increases above this characteristic concentration, bulk-like free water disappears in aqueous solutions and all water molecules among closely-packed hydrated solutes exhibit the characteristics of confined water.

关键词： aqueous solutions stretching vibration of water concentration dependence hydration number

成人乙型肝炎疫苗无应答者大剂量再免疫效果评价

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现代预防医学 2015年第20期42卷 3783-3785页

作者：宋红潮熊传庆郭艳秋梁绍莲朱丹黄泽强广西医科大学第一附属医院预防保健科

目的探讨2种大剂量乙型肝炎(乙肝)疫苗对无应答成人再免疫的效果,为60μg/1.0 ml乙肝疫苗的临床应用提供依据。方法将有乙肝疫苗全程接种史、乙肝表面抗原(HBs A)g及乙肝表面抗体(抗-HBs)阴性的健康成人,根据知情同意、随机原则分为2组,... 详细信息

目的探讨2种大剂量乙型肝炎(乙肝)疫苗对无应答成人再免疫的效果,为60μg/1.0 ml乙肝疫苗的临床应用提供依据。方法将有乙肝疫苗全程接种史、乙肝表面抗原(HBs A)g及乙肝表面抗体(抗-HBs)阴性的健康成人,根据知情同意、随机原则分为2组,1组为20μg组,即接种3针20μg乙肝疫苗,按"0、1、6"程序;1组为60μg组,即接种1针60μg乙肝疫苗。完成免疫程序后3个月内检测乙肝5项指标。结果无应答成人再免疫后,20μg组和60μg组2组抗-HBs阳转率约为88%,且正常应答者,2组抗-HBs几何平均滴度(GMT)水平相近,差异无统计学意义(P>0.05),低应答者,60μg组抗-HBs GMT高于20μg组(P0.05)。结论 1针60μg/1.0 ml乙肝疫苗和3针20μg/ml乙肝疫苗疗效相当,可根据个体实际情况选择免疫方案。

关键词：乙肝疫苗无应答再免疫大剂量