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Increase of chiral sensing ability in host-guest chemistry by magnetic anisotropy

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science China Chemistry 2024年第8期67卷 2775-2782页

作者： Jia-Liang Chen Bin Li Feng Yang Tiesheng Shi Xun-Cheng Su state key {2. of Elemento-organic Chemistry Tianjin Key Laboratory of Biosensing and Molecular RecognitionCollege of ChemistryNankai UniversityTianjin 300071China College of Chemistry Chemical Engineering and Materials ScienceZaozhuang UniversityZaozhuang 277160China

Enantiomeric molecules generally play distinct functions in chemistry,biology,and *** physical and chemical properties of chiral analytes lay difficulty in discrimination and quantification of the *** report herein an efficient approach of increasing the chiral sensing ability ofβ-cyclodextrin(β-CD),a widely used host molecule,in the hostguest chemistry by magnetic anisotropy.A rigid and chiral lanthanide binding tag was attached to theβ-CD to amplify the changes of nuclear magnetic resonance(NMR)signals in the host-guest recognition *** installation of the paramagnetic lanthanide ion inβ-CD greatly enhances the enantiomeric discrimination up to 30-fold in comparison with the diamagneticβ-CD *** addition,the magnitude of the paramagnetic effects is tunable according to the diverse range of paramagnetic strength of the lanthanide *** reported method significantly increases the chiral sensing ability ofβ-CD,which can be applied to other host *** transferred paramagnetic effects,pseudocontact shifts(PCSs)and paramagnetic relaxation enhancements(PREs),from the host to the guest molecules,are valuable structural restraints to determine the absolute stereochemistry of the chiral *** strategy does not need modification of the analytes and is complementary to the reported analytical methods that rely on the functionalization of the chiral analytes.

关键词： chiral recognition nuclear magnetic resonance host-guest chemistry magnetic anisotropy lanthanide ions

Pressure effects on metal/covalent-organic frameworks:structural and optical properties

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science China Chemistry 2024年第9期67卷 2890-2903页

作者： Yixuan Wang Yunfeng Yang Xinyi Yang Bo Zou Synergetic Extreme Condition High-Pressure science Center State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China

Metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)with highly ordered porous structure,tunable bandgap,large specific surface area and structural diversity,provide an appealing platform for the development of stimulus response,sensing,imaging and *** various tuning methods,pressure engineering using the diamond anvil cell is a highly powerful in-situ technique,which can efficiently modulate the structural and optical properties of MOFs/*** is beyond the realization of traditional chemical *** review outlines the research progress in the experimentoriented discovery of new phases or unique properties under high pressure,including phase transition,abnormal compression,photoluminescence(PL)discoloration and ***,the improvement of PL quantum yield in MOFs could be achieved by pressure-treated engineering and hydrogen-bonding cooperativity *** also propose and establish the relationship between structure and optical properties under high ***,the challenge and outlook of the current fields are *** hope that this review will supply guidance for comprehending the development of high-pressure MOF/COF-related research fields,and offer novel strategies for designing more high-performance MOF/COF materials to ultimately expand their applications.

关键词： metal/covalent-organic frameworks pressure engineering phase transition abnormal compressive behaviors piezochromic behaviors emission enhancement

Synthesis of covalent organic framework materials and their application in the field of sensing

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Nano Research 2024年第1期17卷 162-195页

作者： Weiyu Zhang Shiwei Liu Qihua Sun Ning Tian Zhaofeng Wu Xinjiang key laboratory of Solid-{2. Physics and Devices Urumqi 830046China School of Physics science and Technology Xinjiang UniversityUrumqi 830046China

Covalent organic frameworks(COFs)are an emerging type of porous crystalline polymers formed by combining strong covalent bonds with organic building *** to their large surface area,high intrinsic pore space,good crystallization properties,high stability,and designability of the resultant units,COFs are widely studied and used in the fields of gas adsorption,drug transport,energy storage,photoelectric catalysis,electrochemistry,and *** recent years,the rapid development of the Internet of Things and people’s yearning for a better life have put forward higher and more requirements for sensors,which are the core components of the Internet of ***,this paper reviews the recent progress of COFs in synthesis methods and sensing applications,especially in the last five *** paper first introduces structure,properties,and synthesis methods of COFs and discusses advantages and disadvantages of different synthesis ***,the research progress of COFs in different sensing fields,such as metal ion sensors,gas sensors,biomedical sensors,humidity sensors,and pH sensors,is introduced *** and prospects are also presented in order to provide a reference for researchers concerned with COFs and sensors.

关键词： covalent organic framework materials structural design and synthesis sensing application gas sensors

Design and Control of an Autonomous Bat-like Perching UAV

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Journal of Bionic Engineering 2024年第3期21卷 1253-1264页

作者： Long Bai Wei Wang Xiaohong Chen Yuanxi Sun state key {2. of Mechanical Transmission Chongqing UniversityChongqing400044China

Perching allows small Unmanned Aerial Vehicles(UAVs)to maintain their altitude while significantly extending their flight duration and reducing ***,current research on flying habitats is poorly adapted to unstructured environments,and lacks autonomous capabilities,requiring ideal experimental environments and remote control by *** solve these problems,in this paper,we propose a bat-like UAV perching mechanism by investigating the bat upside-down perching method,which realizes double self-locking in the perching state using the ratchet and four-link dead point *** on this perching mechanism,this study proposes a control strategy for UAVs to track targets and accomplish flight perching autonomously by combining a binocular camera,single-point LiDAR,and pressure *** perching experiments were conducted for crossbar-type objects *** experimental results show that a multirotor UAV equipped with the perching mechanism and sensors can reliably achieve autonomous flight perching and re-flying off the target *** power consumption is reduced to 2.9%of the hovering state when perched on the target object.

关键词： Bio-inspired design Perching mechanism UAV Autonomous flight

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中国湿地保护修复管理经验与未来研究趋势

Journal of Geographical sciences 2024年第2期34卷 229-251页

作者：蒋卫国张泽凌子燕邓雅文 state key {2. of remote sensing science Faculty of Geographical SciencesBeijing Normal UniversityBeijing 100875China key laboratory of Environmental Change and Resource Use in Beibu Gulf Ministry of EducationSchool ofGeography and PlanningNanning Normal UniversityNanning 530001China

Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial *** curb the continued loss of wetlands globally,international organizations and many countries have taken a series of major conservation and restoration *** work reviews these wetland conservation and restoration measures,interprets China’s wetland conservation and restoration management policies,and proposes that future research on wetland resources in China should be conducted from the aspects of international frontiers and national strategic plans,socioeconomics,and smart *** results show that the 2. International Wetlands Days from 1997 to 2.2. provided new goals and tasks for the protection and management of *** important topics and outcomes of the 14 Conferences of the Contracting Parties to the Convention on Wetlands from 1980 to 2.2. provided new directions and new challenges for wetland *** the future,we should enhance wetland ecological functions,promote sustainable wetland development,and overcome the technical bottleneck of fragile wetland ecosystem *** 1992.to 2.2.,China embarked on a new phase of wetland protection and *** overall experience of wetland protection and restoration in China has been formed through national strategic deployment,legal policy establishment,and project planning and *** needs to provide for and plan the long-term protection of wetlands at the national level,to innovate restoration and management techniques and application systems,and to effectively address the complex issues of wetland protection and restoration through collaborative division of labor among multiple departments were *** on the future trends of wetlands should be directed towards the exploration and practice of the United Nations Sustainable Development Goals and several international conventions in support of sustainable wetland development.W

关键词： Convention on Wetlands wetland space wetland protection and restoration management experience high-quality wetland development sustainable wetland development future research trends in wetlands

Knittable and washable aerogel fiber inspired by polar bear hair

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science China Materials 2024年第2期67卷 705-706页

作者： Yue Liu Huisheng Peng state key {2. of Molecular Engineering of Polymers Department of Macromolecular Scienceand Institute of Fiber Materials and DevicesFudan UniversityShanghai 200438China

The advances in chemistry and materials have boosted the development of smart textiles,which are poised to revolutionize human lifestyles through multifunctional integration,such as heating,cooling,sensing and supplying energy^([1,2.).Among them,thermal insulation is an essential function of textiles to protect humans from complex and extreme environments and realize personal thermal management without energy con-sumption^([3]).

关键词： textiles insulation extreme

Mapping upland crop–rice cropping systems for targeted sustainable intensification in South China

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The Crop Journal 2024年第2期12卷 614-629页

作者： Bingwen Qiu Linhai Yu Peng Yang Wenbin Wu Jianfeng Chen Xiaolin Zhu Mingjie Duan key laboratory of Spatial Data Mining&Information Sharing of Ministry of Education Academy of Digital China(Fujian)Fuzhou UniversityFuzhou 350116FujianChina key laboratory of Agricultural {2. sensing Ministry of Agriculture and Rural AffairsBeijing 100081China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Upland crop-rice cropping systems(UCR)facilitate sustainable agricultural *** UCR cultivation mapping is needed to ensure food security,sustainable water management,and rural ***,datasets describing cropping systems are limited in spatial coverage and crop *** UCR is more challenging than crop identification and most existing approaches rely heavily on accurate phenology calendars and representative training samples,which limits its applications over large *** describe a novel algorithm(RRSS)for automatic mapping of upland crop-rice cropping systems using Sentinel-1 Synthetic Aperture Radar(SAR)and Sentinel-2.Multispectral Instrument(MSI)*** indicator,the VV backscatter range,was proposed to discriminate UCR and another two indicators were designed by coupling greenness and pigment indices to further discriminate tobacco or oilseed *** RRSS algorithm was applied to South China characterized by complex smallholder rice cropping systems and diverse topographic *** study developed 10-m UCR maps of a major rice bowl in South China,the Xiang-Gan-Min(XGM)*** performance of the RRSS algorithm was validated based on 5197 ground-truth reference sites,with an overall accuracy of 91.92..There were7348 km^(2. areas of UCR,roughly one-half of them located in *** UCR was represented mainly by oilseed-UCR and tobacco-UCR,which contributed respectively 69%and 15%of UCR *** patterns accounted for only one-tenth of rice production,which can be tripled by intensification from single rice *** to complex and fragmented subtropical regions suggested the spatiotemporal robustness of the RRSS algorithm,which could be further applied to generate 10-m UCR datasets for application at national or global scales.

关键词： Cropping-pattern mapping Paddy rice Sentinel-1/2 China Sustainable intensification

In situ photoelectric biosensing based on ultranarrowband near-infrared plasmonic hot electron photodetection

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Advanced Photonics 2024年第2期6卷 81-89页

作者： Xianghong Nan Wenduo Lai Jie Peng Haiquan Wang Bojun Chen Huifan He Zekang Mo Zikun Xia Ning Tan Zhong Liu Long Wen Dan Gao Qin Chen Jinan University College of Physics & Optoelectronic Engineering Institute of Nanophotonics Guangdong Provincial Key Laboratory of Nanophotonic Manipulation Tsinghua University Shenzhen International Graduate School State Key Laboratory of Chemical Oncogenomics Jinan University College of Life Science and Technology

Narrowband photodetection is an important measurement technique for material analysis and sensing, for example, nondispersive infrared sensing technique. Both photoactive material engineering and nanophotonic filtering schemes have been explored to realize wavelength-selective photodetection,while most devices have a responsive bandwidth larger than 2. of the operating wavelength, limiting sensing performance. Near-infrared photodetection with a bandwidth of less than 0.2. of the operating wavelength was demonstrated experimentally in Au/Si Schottky nanojunctions. A minimum linewidth of photoelectric response down to 2.6 nm was obtained at a wavelength of 1550 nm by carefully tailing the absorptive and radiative loss in the nanostructures. Multiple functions were achieved on chip with the corrugated Au film, including narrowband resonance, light harvesting for sensing and photodetection, and electrodes for hot electron emission. Benefiting from such a unity integration with in situ photoelectric conversion of the optical sensing signal and the ultranarrowband resonance, self-contained on-chip biosensing via simple intensity interrogation was demonstrated with a limit of detection down to 0.0047%in concentration for glucose solution and 150 ng∕m L for rabbit IgG. Promising potential of this technique is expected for the applications in on-site sensing, spectroscopy, spectral imaging, etc.

关键词： Photodetectors Plasmonics Biosensing Optical gratings Gold Absorption spectrum Acoustooptic tunable filters Absorption Sensors In situ remote sensing

Multifunctional MXene/rGO aerogels loaded with Co/MnO nanocomposites for enhanced electromagnetic wave absorption,thermal insulation and pressure sensing

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Nano Research 2024年第9期17卷 7803-7813页

作者： Chan Guo Shiping Shao Xin Zhang Yunxiang Tang Luxue Wang Jiurong Liu Lili Wu Ke Bi Fenglong Wang key laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of Education Shandong UniversityJinan 250061China state key {2. of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

Aerogel-based composites hold promising application prospects as potential electromagnetic wave(EMW)absorption materials,yet the construction of such materials with ingenious microstructures,appropriate magnetic/dielectric multi-components,and integrated multifunctionality remains considerably ***,a multicomponent Co/MnO/Ti_(3)C_(2.T_(x) MXene/rGO(CMMG)hybrid aerogel featured with three-dimensional(3D)vertical directional channel architecture is *** from the synergistic effect arising from the 3D conductive networking structure,diverse heterogeneous interfaces,magnetic/dielectric multicomponent,and multiple loss pathways,the optimized CMMG-2.aerogel delivers fascinating EMW absorption capabilities,characterized by a minimal reflection loss(RL_(min))of-77.41 dB and an effective absorption bandwidth(EAB)of 6.56 ***,the remarkable hydrophobicity,exceptional thermal insulation capabilities,and outstanding photothermal properties of CMMG-2.aerogel make it highly promising for multiple application in diverse and demanding ***,the distinctive pore structure of hybrid aerogel also allows it for sensitive and reliable detection of electrical signals caused by pressure changes and human ***,this research provides a viable design strategy for the development of lightweight,efficient,and multifunctional aerogel-based EMW absorption materials for various application scenarios.

关键词： electromagnetic wave absorption Ti_(3)C_(2.qT_(x)MXene reduced graphene oxide magnetic-dielectric nanoparticles multifunctional aerogel