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Temporally Separated CO_(2) Photoreduction and H_(2)O Photooxidation over Redox-Active Conjugated Organic Polymer Films

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CCS Chemistry 2023年第8期5卷 1854-1865页

作者： guipeng ji Yuepeng Wang Wenqiang Ye Meifang Chen Fengtao Zhang Yanfei Zhao Shengrui Tong Buxing Han Zhimin Liu Beijing National Laboratory for Molecular Sciences Key Laboratory of ColloidInterfaceand ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences(CAS)100190 Beijing University of Chinese Academy of Sciences 100049 Beijing School of Science China University of Geosciences100083 Beijing

Photocatalytic CO_(2) reduction with H_(2)O of chemicals without H2 generation is interesting but challenging.Herein,we report temporally separated CO_(2) photoreduction and H_(2)O photooxidation that are achieved over redox-active o-hydroxyazo-based conjugated organic polymer films(HAzo-COPFs),affording CO with high efficiency as the sole reduction product.HAzo-COPFs are prepared via interfacial diazo-coupling reactions of aromatic diamines and diphenols,and HAzo-COPF-1 from 4,4′-biphenol and benzidine shows the best performance with a CO generation rate of 53.6μmol g−1 h−1 under visible-light irradiation(>420 nm).Interestingly,we discovered that diphenol(DP-OH)moieties in HAzo-COPFs,serving as electron and proton donors to participate in CO_(2) photoreduction,are oxidized into quinone(DP=O)moieties,which are subsequently photoreduced to regenerate DP-OH in H_(2)O photooxidation.Consequently,CO_(2) photoreduction and H_(2)O photooxidation are temporally separated and perfectly coupled via redox transformation between DP-OH and DP=O that form in situ,affording enhanced charge carrier separation and inhibiting the hydrogen evolution reaction.This work provides new insights for the design of COP photocatalysts and artificial photosynthesis.

关键词： CO_(2)photoreduction conjugated organic polymers carbon monoxide redox transformation artificial photosynthesis

Rational Design of Layered SnS2 on Ultralight Graphene Fiber Fabrics as Binder-Free Anodes for Enhanced Practical Capacity of Sodium-Ion Batteries

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Nano-Micro Letters 2019年第4期11卷 173-184页

作者： Zongling Ren jie Wen Wei Liu Xiaoping jiang Yanheng Dong Xiaolong Guo Qiannan Zhao guipeng ji Ronghua Wang Ning Hu Baihua Qu Chaohe Xu College of Aerospace Engineering The State Key Laboratory of Mechanical TransmissionsChongqing UniversityChongqing 400044People’s Republic of China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005People’s Republic of China College of Materials Science and Engineering Chongqing UniversityChongqing 400044People’s Republic of China MOE Key Laboratory of Low-grade Energy Utilization Technologies and Systems CQU-NUS Renewable Energy Materials and Devices Joint LaboratoryChongqing UniversityChongqing 400044People’s Republic of China

Generally,the practical capacity of an electrode should include the weight of non-active components such as current collector,polymer binder,and conductive additives,which were as high as 70 wt%in current reported works,seriously limiting the practical capacity.This work pioneered the usage of ultralight reduced graphene fiber(rGF)fabrics as conductive scaffolds,aiming to reduce the weight of nonactive components and enhance the practical capacity.Ultrathin SnS2 nanosheets/rGF hybrids were prepared and used as binder-free electrodes of sodium-ion batteries(SIBs).The interfused graphene fibers endow the electrode a porous,continuous,and conductive network.The in situ phase transformation from SnO2 to SnS2 could preserve the strong interfacial interactions between SnS2 and graphene.Benefitting from these,the designed binder-free electrode delivers a high specific capacity of 500 mAh g?1 after 500 cycles at a current rate of 0.5 A g?1 with almost 100%Coulombic efficiency.Furthermore,the weight percentage of SnS2 in the whole electrode could reach up to 67.2 wt%,much higher than that of common electrode configurations using Cu foil,Al foil,or carbon cloth,significantly highlighting the ultralight characters and advantages of the rGF fabrics for using as binder-free electrodes of SIBs.

关键词： SnS2 Graphene fiber fabric Binder-free electrode Practical capacity Sodium-ion batteries

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基于北斗三号短报文的应急图文信息传输技术

沈阳航空航天大学学报 2024年第1期41卷 61-67页

作者：王尔申贾帅王明阳纪贵鹏吴建强徐嵩杨健沈阳航空航天大学电子信息工程学院沈阳110136 沈阳航空航天大学辽宁通用航空研究院沈阳110136 北京星桥恒远导航科技股份有限公司研发部北京100089

为提高应急救援服务能力,提出一种基于北斗三号短报文的应急图文信息传输技术,并设计了基于北斗三号的应急图文信息传输平台。为提高北斗短报文信息传输效率,提出文本和图像压缩编码算法,将文本和图像信息压缩成信息容量更小的数据包,... 详细信息

为提高应急救援服务能力,提出一种基于北斗三号短报文的应急图文信息传输技术,并设计了基于北斗三号的应急图文信息传输平台。为提高北斗短报文信息传输效率,提出文本和图像压缩编码算法,将文本和图像信息压缩成信息容量更小的数据包,缩短了信息传输所需数据包的长度。实验结果表明,该算法对文本消息的压缩率达到50%,图像信息的压缩率达到2%。平台测试结果表明,在有限的通信资源下,终端与指挥机之间能够高效地进行信息交互,有助于更快速地响应应急情况。该研究成果对应急管理部门提高应急救援服务能力具有一定参考价值。

关键词：应急救援北斗卫星导航系统图像压缩文字编码北斗短报文

吡咯氮配位单原子铜催化剂的电催化二氧化碳还原性能

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高等学校化学学报 2022年第7期43卷 159-165页

作者：赵润瑶纪桂鹏刘志敏中国科学院化学研究所北京分子科学国家研究中心中国科学院胶体、界面与化学热力学重点实验室中国科学院分子科学科教融合卓越创新中心北京100190 中国科学院大学北京100049

采用温度控制的浸渍-热解法,合成了以碳纳米管为载体的一系列铜单原子催化剂.扩展X射线吸收精细结构(EXAFS)分析表明,催化剂中的单原子铜位点分别由吡啶氮和吡咯氮配位.电催化性能测试表明,所制备催化剂可用于电催化二氧化碳生成一氧化... 详细信息

采用温度控制的浸渍-热解法,合成了以碳纳米管为载体的一系列铜单原子催化剂.扩展X射线吸收精细结构(EXAFS)分析表明,催化剂中的单原子铜位点分别由吡啶氮和吡咯氮配位.电催化性能测试表明,所制备催化剂可用于电催化二氧化碳生成一氧化碳,由吡啶氮配位的铜单原子催化剂的反应选择性较差,而由吡咯氮配位的铜单原子催化剂则具有更强的活性,CO法拉第效率在−0.70 V(vs.RHE)时可达到96.3%;吡咯氮配位的铜单原子中心对于析氢反应具有更好的抑制效果.

关键词：单原子催化剂碳纳米管扩展X射线吸收精细结构电催化二氧化碳还原一氧化碳

Biogenic production of DMSP and its degradation to DMS—their roles in the global sulfur cycle

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Science China(Life Sciences) 2019年第10期62卷 1296-1319页

作者： Xiao-Hua Zhang ji Liu jingli Liu guipeng Yang Chun-Xu Xue Andrew R. J. Curson Jonathan D. Todd MOE Key Laboratory of Marine Genetics and Breeding College of Marine Life SciencesOcean University of ChinaQingdao 266003China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266071China School of Biological Sciences University of East AngliaNorwich NR4 7TJUK

Dimethyl sulfide(DMS) is the most abundant form of volatile sulfur in Earth’s oceans, and is mainly produced by the enzymatic clevage of dimethylsulfoniopropionate(DMSP). DMS and DMSP play important roles in driving the global sulfur cycle and may affect climate. DMSP is proposed to serve as an osmolyte, a grazing deterrent, a signaling molecule, an antioxidant, a cryoprotectant and/or as a sink for excess sulfur. It was long believed that only marine eukaryotes such as phytoplankton produce DMSP. However, we recently discovered that marine heterotrophic bacteria can also produce DMSP, making them a potentially important source of DMSP. At present, one prokaryotic and two eukaryotic DMSP synthesis enzymes have been identified.Marine heterotrophic bacteria are likely the major degraders of DMSP, using two known pathways: demethylation and cleavage.Many phytoplankton and some fungi can also cleave DMSP. So far seven different prokaryotic and one eukaryotic DMSP lyases have been identified. This review describes the global distribution pattern of DMSP and DMS, the known genes for biosynthesis and cleavage of DMSP, and the physiological and ecological functions of these important organosulfur molecules, which will improve understanding of the mechanisms of DMSP and DMS production and their roles in the environment.

关键词： marine microorganism dimethylsulfoniopropionate (DMSP) dimethyl sulfide (DMS) DMSP biosynthesis DMSP cleavage

Metabolic engineering of Streptomyces to enhance the synthesis of valuable natural products

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Engineering Microbiology 2022年第2期2卷 29-36页

作者： Zuwei Xu Lihao ji Wenxiu Tang Liang Guo Cong Gao Xiulai Chen jia Liu guipeng Hu Liming Liu State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxi 214122China School of Life Sciences and Health Engineering Jiangnan UniversityWuxi 214122China

The mycelial bacterium Streptomyces is a workhorse for producing natural products,serving as a key source of drugs and other valuable chemicals.However,its complicated life cycle,silent biosynthetic gene clusters(BGCs),and poorly characterized metabolic mechanisms limit efficient production of natural products.There-fore,a metabolic engineering strategy,including traditional and emerging tools from different disciplines,was developed to further enhance natural product synthesis by Streptomyces.Here,current trends in systems metabolic engineering,including tools and strategies,are reviewed.Particularly,this review focuses on recent developments in the selection of methods for regulating the Streptomyces life cycle,strategies for the activation of silent gene clusters,and the exploration of regulatory mechanisms governing antibiotic production.Finally,future challenges and prospects are discussed.

关键词： Streptomyces Natural products Metabolic engineering Life cycle Biosynthetic gene clusters

多组分氧化石墨烯/聚醚胺/碳纳米管层级结构碳纤维复合材料的制备及性能研究

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化工新型材料 2023年第6期51卷 85-89,93页

作者：权贵鹏冀晨曦冷金澎薛鸿莹肖凌寒长春工业大学化学与生命科学学院吉林省碳纤维开发与应用重点实验室长春130012

利用层层自组装法在碳纤维表面构建多组分氧化石墨烯/聚醚胺/碳纳米管,在碳纤维表面构建新型界面相,从而提高碳纤维与树脂基体的结合能力。采用傅里叶红外光谱仪(FT-IR)和显微共焦拉曼光谱仪分析了碳纤维表面结构和官能团,采用热导仪测... 详细信息

利用层层自组装法在碳纤维表面构建多组分氧化石墨烯/聚醚胺/碳纳米管,在碳纤维表面构建新型界面相,从而提高碳纤维与树脂基体的结合能力。采用傅里叶红外光谱仪(FT-IR)和显微共焦拉曼光谱仪分析了碳纤维表面结构和官能团,采用热导仪测试了碳纤维复合材料的热导率,采用万能试验机测试了碳纤维复合材料的层间剪切强度(ILSS)、复合材料的弯曲强度和弯曲模量。结果表明:当碳纤维表面氧化石墨烯/聚醚胺/碳纳米管循环组装2次后,碳纤维复合材料的热导率提高了51.5%,层间剪切强度提高了52.2%,弯曲强度和弯曲模量分别提高了33.3%和60.1%。

关键词：层层自组装层级结构机械性能

南海北部海水中氨基酸的分布及其对溶解有机物降解行为的指示研究

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海洋学报 2017年第9期39卷 58-70页

作者：陈岩杨桂朋纪崇霄杨程中国海洋大学化学化工学院海洋化学理论与工程技术教育部重点实验室山东青岛266100 青岛海洋科学与技术国家实验室海洋生态与环境科学功能实验室山东青岛266100

于2015年6月对南海北部海区5个断面共26个站位海水中溶解态氨基酸(THAA)、溶解有机碳(DOC)和叶绿素a(Chl a)的浓度进行了科学调查。结果表明:夏季南海北部海水中THAA的浓度范围为0.40~1.95μmol/L,平均值为(0.80±0.40)μmol/L,THAA的... 详细信息

于2015年6月对南海北部海区5个断面共26个站位海水中溶解态氨基酸(THAA)、溶解有机碳(DOC)和叶绿素a(Chl a)的浓度进行了科学调查。结果表明:夏季南海北部海水中THAA的浓度范围为0.40~1.95μmol/L,平均值为(0.80±0.40)μmol/L,THAA的水平分布总体上体现出近岸高、远海低的特点,表明陆源输入对南海北部海域表层THAA分布有重要影响。THAA在断面上的垂直分布呈现出由近岸至远岸、由表层至底层逐渐降低的趋势。THAA浓度与两种D型氨基酸(D-谷氨酸:D-Glu和D-丙氨酸:D-Ala)含量之间存在显著负相关性,与天门冬氨酸/β-丙氨酸(Asp/β-Ala)和谷氨酸/γ-氨基丁酸(Glu/γ-Aba)比值之间存在显著正相关性,表明细菌的消耗是影响南海海水中THAA浓度的重要因素。D-Ala作为细菌肽聚糖中相对稳定的氨基酸,根据其占DOC的含量估算南海海水中的细菌源有机碳对DOC的贡献率为(29.32±14.32)%,其水平分布显示出近岸低、远岸高的特点;而其垂直分布则呈现出从表层至底层逐渐增加的趋势。THAA占DOC百分比(THAAC%)的变化范围为1.02%~5.49%,平均值为(2.97±1.38)%。THAA-C%、活性因子和降解因子的高值均出现在珠江口外围区域。随着海水深度增加3种降解因子的数值均显著降低,这表明底层海水中有机物比表层海水中的有机物降解程度更大。

关键词：溶解态氨基酸溶解有机碳细菌降解南海

深度学习LSTM模型的电离层总电子含量预报

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导航定位学报 2019年第3期7卷 76-81页

作者：吉长东王强王贵朋刘亚南辽宁工程技术大学测绘与地理科学学院辽宁阜新123000 日照市城乡建设勘察测绘院有限公司山东日照276800

针对TEC时间序列高噪声、非线性和非平稳的动态序列的特性,基于分解-预测-重构的思想,运用总体经验模态分解和深度学习长短期记忆神经网络,构建了EEMD-LSTM预测模型。同时,以测试集上预测结果的均方根误差最小为目标,运用多层网格搜索... 详细信息

针对TEC时间序列高噪声、非线性和非平稳的动态序列的特性,基于分解-预测-重构的思想,运用总体经验模态分解和深度学习长短期记忆神经网络,构建了EEMD-LSTM预测模型。同时,以测试集上预测结果的均方根误差最小为目标,运用多层网格搜索算法对EMD-LSTM预测模型进行参数优选。以IGS中心2015年全年1 h时间尺度的TEC格网数据进行实验分析,结果表明,EEMD-LSTM组合模型的预报结果能够很好的反应电离层TEC的变化特性,在低、中、高纬度地区平均预报残差分别为1.37、0.82和0.96个TECu,预测平均相对精度分别为92.8%、91.9%和87.8%。

关键词：长短期记忆神经网络递归神经网络总体经验模态分解电离层总电子含量时间序列