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Green Energy & Environment 2024年第3期9卷 507-515页

作者： Ying-Xi Dang peng tan Bin Hu Chen Gu Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing211816China

Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption.

关键词： CO_(2)capture Solar heating Passive radiative cooling Temperature swing adsorption

Enhancing photoresponsiveness of metal-organic polyhedra by modifying microenvironment

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Nano Research 2024年第6期17卷 5712-5717页

作者： Long Zheng peng tan Qian Song Sheng-Tao Wang Min Li Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

Photoresponsiveness of materials is critical to their tunability and efficiency in terminal applications.Photoresponsive metal-organic polyhedra(PMOPs)feature intrinsic pores and remote controllability,but aggregation of PMOPs in solid state hampers their photoresponsiveness seriously.Herein,we report the construction of a new PMOP(Cu_(24)(C_(16)H_(12)N_(2)O_(4))_(12)(C_(18)H_(22)O_(5))12,denoted as MOP-PR-LA),where long alkyl(LA)chains act as the intermolecular poles,propping against adjacent PMOP molecules to create individual microenvironment benefiting the isomerization of photoresponsive(PR)moieties.Upon ultraviolet(UV)-and visible-light irradiation,MOP-PR-LA is much easier to isomerize than the counterpart MOP-PR without LA.For propylene adsorption,MOP-PR has a low change of adsorption capacity(9.9%),while that of MOP-PR-LA reaches 58.6%.Density functional theory calculations revealed that PR in the cis state has a negative effect on adsorption,while the trans state of PR favors adsorption.This work might open an avenue for the construction of photoresponsive materials with high responsiveness and controllability.

关键词： photoresponsive adsorption metal-organic polyhedra azobenzene long alkyl chains propylene capture

Graphene-anchored sodium single atoms:A highly active and stable catalyst for transesterification reaction

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Nano Research 2024年第6期17卷 4979-4985页

作者： Song-Song peng Yao Nian Xing-Ru Song Xiang-Bin Shao Chen Gu Zhi-Wei Xing Shi-Chao Qi peng tan You Han Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu RoadNanjing 211816China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Solid strong base catalysts have received considerable attention in various organic reactions due to their facile separation,neglectable corrosion,and environmental friendliness.Although great progress has been made in the preparation of solid strong base catalysts,it is still challenging to avoid basic sites aggregation on support and active sites loss in reaction system.Here,we report a tandem redox strategy to prepare Na single atoms on graphene,producing a new kind of solid strong base catalyst(Na1/G).The base precursor NaNO_(3)was first reduced to Na2O by graphene(400℃)and successively to single atoms Na anchored on the graphene vacancies(800℃).Owing to the atomically dispersed of basicity,the resultant catalyst presents high activity toward the transesterification of methanol and ethylene carbonate to synthesize dimethyl carbonate(turnover frequency(TOF)value:125.7 h^(−1)),which is much better than the conventional counterpart Na2O/G and various reported solid strong bases(TOF:1.0-90.1 h^(−1)).Furthermore,thanks to the basicity anchored on graphene,the Na1/G catalyst shows excellent durability during cycling.This work may provide a new direction for the development of solid strong base catalysts.

关键词： solid strong base catalyst basic sites redox graphene single Na atoms

Geoacoustic inversion in shallow water by matching the vertical-particle-velocity

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Chinese Journal of Acoustics 2023年第3期42卷 288-306页

作者： tan peng SUN Mei QIN Jixing YANG Desen Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001 School of Physics and Electronic Engineering Taishan UniversityTaian 271000 State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencessBeijing 100190

Bottom acoustic parameters are vital for studying sound propagation properties and their applications in ocean waveguides.The propagation properties and normal-mode structure of vertical-particle-velocity in an ocean environment with a thermocline in shallow water were studied in the Yellow Sea.The Results reveal that high energy of the verticalparticle-velocity exists at most depth except for near-bottom depth when the source and receiver are both below the thermocline.Moreover,high-order modes contribute more to the verticalparticle-velocity and vertical-particle-velocity-based matched-field-processing(MFP)inversion method can be highly sensitive to bottom parameters compared to sound pressure.Furthermore,the effects of the bottom absorption coefficient on the vertical-particle-velocity-based MFP inversion method are studied.It is shown that accurate sound velocity,density and water depth can be obtained only when the bottom absorption coefficient is set close to the real value during MFP.By using the vertical-particle-velocity signals recorded by vector hydrophones during the experiment and determining the bottom sound velocity,bottom density and water depth under different bottom absorption coefficients,stable inversion results were obtained.The transmission losses of the sound pressure at different ranges were used to invert the bottom absorption coefficients.The transmission losses of sound pressure calculated using the inverted bottom parameters are consistent with the experimental results obtained from the pressure hydrophones in the experiment.

关键词： shallow ocean particle

Multipath matching pursuit using a cross-validation technique for sparse direction-of-arrival estimation with an acoustic vector array

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Chinese Journal of Acoustics 2023年第2期42卷 153-170页

作者： tan peng HU Bo ZHANG Youwen WU Yuquan YANG Desen Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001 School of Electronics and Information Jiangsu University of Science and TechnologyZhenjiang 212100 Science and Technology on Integrated Information System Laboratory Institute of SoftwareChinese Academy of SciencesBeijing 100190

High-resolution direction-of-arrival(DOA)estimations and the starboard ambiguity of moving underwater targets have always been key issues in underwater acoustic array signal processing.Compared with sound pressure arrays,vector arrays have natural advantages with respect to solving the starboard ambiguity problem and obtaining higher processing gains.Traditional high-resolution DOA estimation methods such as Capon have disadvantages such as being unable to resolve coherent sources,requiring multiple snapshot processing,and being sensitive to array manifold errors.High-resolution DOA estimation and the starboard ambiguity of moving underwater targets have always been challenging research topics.On one hand,maneuvering underwater targets reduce the coherence time of the received signals,which ultimately leads to poor performance when using high-resolution DOA estimation technologies based on the covariance matrix of the received signal.On the other hand,traditional DOA estimation technologies based on sound pressure arrays have the problem of port and starboard ambiguity,which can be solved by maneuvering the sonar platform.However,maneuvering the sonar platform can impair the coherence of the received signal,on which some algorithms rely.This approach greatly limits the combat effectiveness and performance of the platform.Given the aforementioned problems and taking advantage of the target sparsity,a cross-validation multipath matching pursuit technique based on the sparse DOA estimation of an acoustic vector array is proposed in this article for sonar observations.The proposed algorithm uses cross-validation technology to achieve a sparse DOA estimation with an unknown number of targets in a sonar observation scene.Compared with the conventional acoustic vector array-based Capon algorithm,the proposed algorithm can achieve a sparse DOA estimation and high-resolution capability with small numbers of snapshots or even single snapshots.The effectiveness of the proposed algorithm is verified via simulations and sea t

关键词： multipath estimation underwater

基于自适应直方图均衡化的医学图像可逆对比度增强算法

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计算机科学 2024年第S1期51卷 382-388页

作者：谭碰欧博湖南大学信息科学与工程学院长沙410082

目前,一些可逆数据隐藏算法通常是对图像进行类似直方图均衡化的信息嵌入操作来实现对比度增强。这类方法虽然简单有效,但是缺乏明确的目标函数来指引参数选择,难以优化对比度增强效果,因而容易产生增强不足或过度增强等问题。为了优化... 详细信息

目前,一些可逆数据隐藏算法通常是对图像进行类似直方图均衡化的信息嵌入操作来实现对比度增强。这类方法虽然简单有效,但是缺乏明确的目标函数来指引参数选择,难以优化对比度增强效果,因而容易产生增强不足或过度增强等问题。为了优化可逆信息嵌入后的对比度增强效果,提出了一种基于自适应直方图均衡化并结合对比度增强的医学图像可逆数据隐藏算法。该方法基于预测误差扩展技术来实现可逆数据嵌入,并通过所定义的自适应直方图均衡化目标函数来优化预测残差直方图的修改,确定最优的数据嵌入点,在确保对比度增强的前提下实现低失真的可逆嵌入。实验结果表明,相比同类算法,所提方法在实现可逆嵌入的同时,能够进一步增强图像对比度,辅助提升医学图像中的目标识别效率。

关键词：医学图像处理可逆对比度增强自适应直方图均衡化预测误差扩展

Aqueous Preparation of Highly Dispersed Hydroxyapatite Nanorods for Colloidal Liquid Crystals

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Journal of Wuhan University of Technology(Materials Science) 2021年第2期36卷 230-238页

作者：熊焰 tan peng LIU Qi LIU Kaixuan 谭军军 Hubei Provincial Key Laboratory of Green Materials for Light Industry7 Hubei University of TechnologyWuhan 40068China Jiangxi Provincial Engineering Research Center for Multifunction Zirconia Materials Jiangxi Size Materials Co.LtdJiujiang 332500China Jiangxi De Corematrix Co. Ltd.Jiujiang 332500China

Hydroxyapatite(HA)nanorods were synthesized using a citrate-assisted hydrothermal method.NaH2PO4,Na2HPO4,and Na3PO4 were used as the phosphate sources and the influences of pH value were investigated.The XRD results show that pure hexagonal HA can be synthesized using Na3PO4·12H2O as the phosphate source with the citrate solution pH ranging from 5.0 to 7.6.The zeta potential evaluation demonstrates that as-synthesized HA nanorods are colloidally stable and the aqueous dispersion can be maintained homogenous without any sediment or creaming for more than at least a month.The Ca/P molar ratio of the HA nanorods is about 1.60,indicating that the HA nanorods are calcium-deficient hydroxyapatite.Besides,owing to the excellent colloidal stability and rod-like morphology with a high aspect ratio(>6),the HA aqueous dispersion undergoes a phase transition from an isotropic state to a liquid crystalline state upon increasing the particle concentration to 17wt%.The completely liquid crystalline phase forms when the particle concentration reaches above 30wt%.

关键词： hydroxyapatite liquid crystal colloidal stability

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锌电池中钴基正极材料的应用现状与挑战

材料导报 2024年第6期38卷 8-17页

作者：尚文旭俞文涛何义马彦义谈鹏中国科学技术大学热科学和能源工程系合肥230026 深空探测实验室(天都实验室) 合肥230088

受益于丰富的矿产资源、超高的理论容量和卓越的安全性,水系锌电池成为下一代储能设备的有力竞争者。作为锌电池理想的正极材料候选者,近年来钴基电极材料因其高输出电压、高理论容量和优异的氧化还原能力(Co^(2+)←→Co^(3+)←→Co^(4... 详细信息

受益于丰富的矿产资源、超高的理论容量和卓越的安全性,水系锌电池成为下一代储能设备的有力竞争者。作为锌电池理想的正极材料候选者,近年来钴基电极材料因其高输出电压、高理论容量和优异的氧化还原能力(Co^(2+)←→Co^(3+)←→Co^(4+))而受到越来越多的关注。虽然研究者对应用于锌空气电池的钴基催化剂进行了文献综述,但是主要集中在单一催化方向,缺乏关于钴基电极材料多功能特性的系统总结。本文介绍了钴基正极材料在锌电池中的多功能特性,结合其氧化还原和氧催化两方面能力,从锌钴电池拓展到复合锌钴电池体系。然后,从两种电池体系中的充放电机理出发,详细介绍了当前锌钴电池中钴基材料的优化策略,以及复合锌钴电池中电极/电解液三相界面的设计方案。最后,本文介绍了当前研究的不足,并对未来研究方向进行了展望。

关键词：钴基材料锌钴电池复合锌钴电池

北京市医务人员付出回报失衡与工作压力的关系研究

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中国全科医学 2024年第7期27卷 843-848页

作者：李昂郭默宁谭鹏路凤王梅北京市卫生健康大数据与政策研究中心 100034

背景医务工作具有挑战性高、任务重和压力大的特点。付出-回报失衡(ERI)模型认为,如果组织环境造成了ERI,会对员工产生负面影响。医务人员调查是2018年全国第六次卫生服务调查的重要组成部分,医务人员的良好工作感受和工作状态是居民服... 详细信息

背景医务工作具有挑战性高、任务重和压力大的特点。付出-回报失衡(ERI)模型认为,如果组织环境造成了ERI,会对员工产生负面影响。医务人员调查是2018年全国第六次卫生服务调查的重要组成部分,医务人员的良好工作感受和工作状态是居民服务利用和健康改善的重要决定因素,提高医务人员的获得感和满意度也是新医改的重要目标。目的探讨北京市医务人员ERI与工作压力的关系,为降低医务人员的工作压力提供参考。方法本研究数据来源于2018年全国第六次卫生服务调查中对北京市4156名医务人员的抽样调查结果。根据医务人员的ERI量表和工作压力量表得分,构建工作压力结构方程预测模型,使用偏最小平方法估计相关参数,分析ERI与工作压力之间的关系。结果参与付出回报比(ERI指数)计算的有效记录为4098条,根据ERI指数计算结果,1333名(32.53%)医务人员处于付出与回报平衡状态,2765名(67.47%)医务人员处于付出与回报失衡状态。北京市医务人员46.00%的工作压力可通过ERI模型进行解释。内在付出、外在付出、工作回报对工作压力均具有直接影响(P<0.001),其中内在付出的总效应为0.409(95%CI=0.373~0.443),外在付出的总效应为0.583(95%CI为0.559~0.606),工作回报的总效应为-0.199(95%CI=-0.227~-0.171)。另外,内在付出是外在付出和工作回报对工作压力影响的中介因子(P<0.001)。结论研究结果支持ERI是北京市医务人员工作压力重要来源的研究假设。鉴于内在付出对工作压力影响最大,卫生管理部门和医疗机构应针对性地改善相关管理制度,解决ERI问题,降低医务人员的工作压力。

关键词：医务人员工作压力付出-回报失衡结构方程模型偏最小平方法北京市

Seasonal dynamics of meiofaunal distribution in the Dagu River Estuary, Jiaozhou Bay, China

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Acta Oceanologica Sinica 2017年第12期36卷 79-86页

作者： YIN Shengle tan peng YUAN Chao HU Jin LIU Xiaoshou College of Marine Life Sciences Ocean University of China Graduate School of Frontier Sciences/Atmosphere and Ocean Research Institute The University of Tokyo

Sediment samples were collected in the intertidal zone of the Dagu River Estuary, Jiaozhou Bay, China in April,July and October 2010 and February 2011 for examining seasonal dynamics of meiofaunal distribution and their relationship with environmental variables. A total of ten meiofaunal taxa were identified, including free-living marine nematodes, benthic copepods, polychaetes, oligochaetes, bivalves, ostracods, cnidarians, turbellarians,tardigrades and other animals. Free-living marine nematodes were the most dominant group in both abundance and biomass. The abundances of marine nematodes were higher in winter and spring than those in summer and autumn. Most of the meiofauna distributed in the 0–2 cm sediment layer. The abundance of meiofauna in hightidal zone was lower than those in low-tidal and mid-tidal zones. Results of correlation analysis showed that Chlorophyll a was the most important factor to influence the seasonal dynamics of the abundance, biomass of meiofauna and abundances of nematodes and copepods. CLUSTER analysis divided the meiofaunal assemblages into three groups and BIOENV results indicated that salinity, concentration of organic matter, sediment sorting coefficient and sediment median diameter were the main environmental factors influencing the meiofaunal assemblages.

关键词： meiofauna seasonal dynamics tidal flat Dagu River Estuary Jiaozhou Bay China