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声共振强化HBIW氢解脱苄合成TADB

火炸药学报 2022年第5期45卷 639-644页

作者：唐晓飞张瑶廉鹏朱军臣张圣龙王锡杰刘宁陈松西安近代化学研究所陕西西安710065

为提高六苄基六氮杂异伍兹烷(HBIW)氢解脱苄反应的“气-液-固”多相间传质效率,以HBIW和H_(2)为原料、Pd(OH)_(2)/C为催化剂,在声共振强化反应器作用下,经氢解脱苄反应合成四乙酰基二苄基六氮杂异伍兹烷(TADB);利用核磁共振谱(^(1)H-NMR... 详细信息

为提高六苄基六氮杂异伍兹烷(HBIW)氢解脱苄反应的“气-液-固”多相间传质效率,以HBIW和H_(2)为原料、Pd(OH)_(2)/C为催化剂,在声共振强化反应器作用下,经氢解脱苄反应合成四乙酰基二苄基六氮杂异伍兹烷(TADB);利用核磁共振谱(^(1)H-NMR,^(13)C-NMR)和高分辨质谱(HRMS)对产物结构进行了表征;通过单因素实验和正交实验研究了反应温度、反应时间、加速度和反应压力对收率的影响,并与传统的釜式反应进行了对比,分析了声共振技术强化反应过程的机理。结果表明,在反应原料为1.5g HBIW、0.15g质量分数10%的Pd(OH)_(2)/C催化剂、5mL Ac_(2)O、7mL DMF和0.1g PhBr的条件下,反应加速度为392m/s^(2),反应压力0.2MPa,18℃反应30min,45℃反应60min,产物TADB收率83%。在以上反应条件下,声共振强化技术与传统釜式工艺相比,产物TADB收率没有变化,但反应时间由18h缩短至90min,时间缩短了91.7%。声共振强化反应传质的原因是改善了氢气在液相中的分散,增大了相间的接触面积,从而提高了反应效率,缩短了反应时间。

关键词：有机化学声共振技术四乙酰基二苄基六氮杂异伍兹烷 TADB 六硝基六氮杂异伍兹烷 HBIW 氢解脱苄反应

不同幅度的实验增温对藏北高寒草甸净生态系统碳交换的影响

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植物生态学报 2016年第12期40卷 1219-1229页

作者：朱军涛陈宁张扬建刘瑶杰拉萨高原生态试验站生态系统网络观测与模拟重点实验室中国科学院地理科学与资源研究所北京100101 中国科学院青藏高原地球科学卓越创新中心北京100101 中国科学院大学北京100049

全球气候变暖将对陆地生态系统(尤其是高寒草甸生态系统)碳循环产生深远影响。该研究依托中国科学院地理科学与资源研究所藏北高原草地生态系统研究站(那曲站),设置不同增温幅度实验,模拟未来2℃增温和4℃增温的情景,探究不同增温幅度... 详细信息

全球气候变暖将对陆地生态系统(尤其是高寒草甸生态系统)碳循环产生深远影响。该研究依托中国科学院地理科学与资源研究所藏北高原草地生态系统研究站(那曲站),设置不同增温幅度实验,模拟未来2℃增温和4℃增温的情景,探究不同增温幅度对青藏高原高寒草甸净生态系统碳交换(NEE)的影响。研究结果显示:1)在2015年生长季(6–9月),不增温和2℃增温处理下NEE小于0,总体表现为碳汇,而4℃增温处理下NEE大于0,总体表现为碳源;2)在生长季的6月、8月及整个生长季,与不增温相比,4℃增温处理显著提高了NEE,而2℃增温处理没有显著改变NEE;7月,2℃和4℃增温处理均显著提高了NEE;3)在半干旱的高寒草甸生态系统,土壤水分是决定NEE的关键因素,增温通过降低土壤水分而导致高寒草甸生态系统碳汇能力下降。该研究可为青藏高原高寒草甸生态系统应对未来气候变化提供基础数据和理论依据。

关键词：气候变暖高寒草甸净生态系统碳交换碳收支藏北高原

Research progress in metal-organic frameworks and their derivatives in electrochemistry

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Science China Chemistry 2025年

作者： Lingling chen Yuxin Liu Yichun Su Wenchen zhu Guangyu Du Huan Pang School of Chemistry and Chemical Engineering Yangzhou University Department of Applied Physics The Hong Kong Polytechnic University Interdisciplinary Materials Research Center Institute for Advanced Study Chengdu University State Key Laboratory of Coordination Chemistry Nanjing University

Metal-organic frameworks (MOFs) are distinguished by their unique porosity and meticulously ordered framework structures,setting them apart from conventional complexes. These materials are defined by their highly organized crystalline and pore structures, extensive surface areas, robust porosity, and superior adsorption capabilities. Owing to their exceptional structural and functional attributes, MOFs and their derivatives are leveraged across a broad spectrum of applications, demonstrating significant potential across diverse sectors. In recent times, the scientific community has increasingly focused on MOFs, underscoring their growing importance in research. Despite the promising array of applications for MOFs and their derivatives,challenges persist in practical deployments, and the pathway to research advancement remains daunting. This document delves into the synthesis and various applications of MOFs and their derivatives, particularly in the domains of energy storage, catalysis,sensing, and water treatment. It also highlights the ongoing research progress in the field of electrochemistry, including developments in lithium ion batteries (LIBs), lithium-sulfur batteries (LSBs), zinc-ion batteries (ZIBs), aqueous nickel-zinc batteries (NZBs), and supercapacitors. Finally, it provides an outlook on the future prospects and potential hurdles facing the development of MOF materials.

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Specific staining and precise killing of cancer cells through fusion of pharmaceutical chemistry and π-bridge effect design philosophy

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Science China Chemistry 2025年

作者： Qiong Liu Qiyun Deng Changxu zhu Kongqi chen Lidan chen Zhaohui Sun Ben Zhong Tang Zhiming Wang AIE Institute Center for Aggregation-Induced Emission State Key Laboratory of Luminescent Materials and Devices Key Laboratory of Luminescence from Molecular Aggregates of Guangdong Province South China University of Technology Department of Laboratory Medicine General Hospital of Southern Theater Command School of Life Sciences The Chinese University of Hong Kong Shenzhen Institute of Aggregate Science and Technology School of Science and Engineering The Chinese University of Hong Kong HKUST-Shenzhen Research Institute

The development of an advanced phototheranostic platform that combines imaging and therapy in a single agent is an appealing yet challenging *** this study,we successfully constructed three novel fluorescent probes by leveraging pharmaceutical chemistry and the design philosophy of theπ-bridge *** a systematic comparative analysis of their fluorescence properties,water solubility,molecular conformation,and electrostatic potential,we revealed the fundamental principles governing the optical behavior and biological selectivity of these ***,the probe TPhIQ-CNTh demonstrated extended fluorescence in the near-infrared region,a significant aggregation-induced emission (AIE) effect,and the ability to distinguish tumor cells from normal ***,it efficiently generated reactive oxygen species (ROS) and specifically labeled lipid droplets,enabling the precise staining and killing of cancer *** study presents a practical strategy for designing precise tumor treatments that integrate efficient imaging-guided photodynamic therapy (PDT) by harnessing the unique properties of AIE materials.

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鲎素的抗菌靶点初探

生物化学与生物物理进展 2008年第5期35卷 563-569页

作者：代建国谢海伟金刚张燕朱俊晨郭勇深圳职业技术学院化生学院深圳518055 华南理工大学生物科学与工程学院广州510640

采用体外抑菌法测定鲎素的抑菌动力学特点,钼酸铵比色法和紫外吸收法分别检测细菌与鲎素共同孵育前后无机磷和大分子泄漏情况,扫描电镜和透射电镜观察细菌与鲎素共同孵育前后细菌形态和结构的变化,紫外吸收法和凝胶电泳法分别观察鲎素... 详细信息

采用体外抑菌法测定鲎素的抑菌动力学特点,钼酸铵比色法和紫外吸收法分别检测细菌与鲎素共同孵育前后无机磷和大分子泄漏情况,扫描电镜和透射电镜观察细菌与鲎素共同孵育前后细菌形态和结构的变化,紫外吸收法和凝胶电泳法分别观察鲎素对细菌基因组DNA和质粒DNA结构的影响,质粒转化实验检测鲎素对质粒DNA复制和转录功能的影响.结果表明,鲎素对革兰氏阳性菌和阴性菌具有不同的抑菌动力学特点,经鲎素处理的细菌,胞内无机磷和大分子泄漏显著,细胞壁膜和菌体遭到不同程度的破坏,鲎素可与细菌基因组DNA和质粒DNA结合,高浓度鲎素有可能使DNA发生断裂,进而使质粒DNA复制和转录功能受到抑制.上述结果提示,鲎素的抗菌靶点至少包括细胞壁膜和菌体DNA.

关键词：鲎素抗菌靶点细胞壁细胞膜 DNA

Alternative Strategy for Development of Dielectric Calcium Copper Titanate‑Based Electrolytes for Low‑Temperature Solid Oxide Fuel Cells

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Nano-Micro Letters 2025年第1期17卷 310-332页

作者： Sajid Rauf Muhammad Bilal Hanif Zuhra Tayyab Matej Veis MAKYousaf Shah Naveed Mushtaq Dmitry Medvedev Yibin Tian chen Xia Martin Motola Bin zhu College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Department of Inorganic Chemistry Faculty of Natural SciencesComenius University BratislavaIlkovicova684215 BratislavaSlovakia Energy Storage Joint Research Center School of Energy and EnvironmentSoutheast UniversityNanjing 210096People’s Republic of China Hydrogen Energy Laboratory Ural Federal University620002 EkaterinburgRussia Laboratory of Electrochemical Devices Based on Solid Oxide Proton Electrolytes Institute of High Temperature Electrochemistry620066 EkaterinburgRussia School of Microelectronics Hubei UniversityWuhan 430062People’s Republic of China

The development of low-temperature solid oxide fuel cells(LT-SOFCs)is of significant importance for realizing the widespread application of *** has stimulated a substantial materials research effort in developing high oxide-ion conductivity in the electrolyte layer of *** this context,for the first time,a dielectric material,CaCu_(3)Ti_(4)O_(12)(CCTO)is designed for LT-SOFCs electrolyte application in this *** individual CCTO and its heterostructure materials with a p-type Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2−δ)(NCAL)semiconductor are evaluated as alternative electrolytes in LT-SOFC at 450–550℃.The single cell with the individual CCTO electrolyte exhibits a power output of approximately 263 mW cm^(-2) and an open-circuit voltage(OCV)of 0.95 V at 550℃,while the cell with the CCTO–NCAL heterostructure electrolyte capably delivers an improved power output of approximately 605 mW cm^(-2) along with a higher OCV over 1.0 V,which indicates the introduction of high hole-conducting NCAL into the CCTO could enhance the cell performance rather than inducing any potential short-circuiting *** is found that these promising outcomes are due to the interplay of the dielectric material,its structure,and overall properties that led to improve electrochemical mechanism in CCTO–***,density functional theory calculations provide the detailed information about the electronic and structural properties of the CCTO and NCAL and their heterostructure CCTO–*** study thus provides a new approach for developing new advanced electrolytes for LT-SOFCs.

关键词： LT-SOFCs Dielectric CaCu_(3)Ti_(4)O_(12) Semiconductor Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2−δ) Ionic conductivity Heterostructure electrolyte

Nitrogen addition promotes soil carbon accumulation globally

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Science China Life Sciences 2025年第1期 284-293页

作者： Xuemei Yang Suhui Ma Erhan Huang Danhua Zhang Guoping chen Jiangling zhu chengjun Ji Biao zhu Lingli Liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

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Nanoparticles for the treatment of spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1665-1680页

作者： Qiwei Yang Di Lu Jiuping Wu Fuming Liang Huayi Wang junjie Yang Ganggang Zhang chen Wang Yanlian Yang Ling zhu Xinzhi Sun Department of Orthopedic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Key Laboratory for Biomedical Effects of Nanomaterials and NanosafetyCAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijingChina University of Chinese Academy of Sciences BeijingChina Department of Neurosurgery The First Affiliated Hospital of Chongqing Medical UniversityChongqingChina

Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development.

关键词： antioxidants axon regeneration biocompatible materials drug carriers nanoparticles nerve regeneration neuroinflammatory diseases neuroprotection spinal cord injury stem cells

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葡萄籽原花青素提取物的保健功能与应用

食品科技 2006年第4期31卷 135-139页

作者：王忠合朱俊晨陈惠音华南理工大学轻工食品学院广州510640 深圳职业技术学院生物应用工程系深圳518055

参考国内外对原花青素的大量研究报道,概述原花青素的抗氧化、保护心血管、抗诱变、抗癌、抗病毒、抗辐射、抗衰老等生物活性作用及其化学结构、安全性和应用,最后展望了其发展前景。

关键词：原花青素葡萄籽提取物自由基抗氧化