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Journal of Environmental Sciences 2013年第7期25卷 1492-1499页

作者： Dina tan Honghu Zeng Jie Liu Xiaozhang Yu Yanpeng Liang Lanjing Lu College of Environmental Science and Engineering Guilin University of Technology Guangxi Institute of Building Research & Design Guangxi Polytechnic of Construction

The kinetics of thedegradation of trace nitrobenzene （NB） by a granular activated carbon （GAC） enhanced microwave （MW）/hydrogen peroxide （H202 ） systemwas studied. Effects of pH, NB initial concentration and tert-butyl alcohol on the removal efficiencywere examined. Itwas found that the reaction rate fitswell to first-order reaction kinetics in the MW/GAC/H202 process. Moreover, GAC greatly enhanced thedegradation rate of NB inwater. Under a given condition （MW power300 W, H202dosage 10 mg/L, pH 6.85 and temperature （60 ± 5）°C）, thedegradation rate of NBwas 0.05214 min 1when4 g/L GACwas added. In general, alkaline pHwas better for NBdegradation; however, the optimum pHwas 8.0 in the tested pH value range of4.0-12.0. At H202dosage of 10 mg/L and GACdosage of4 g/L, the removal of NBwasdecreasedwith increasing initial concentrations of NB, indicating that a low initial concentrationwas beneficial for thedegradation of NB. These results indicated that the MW/GAC/H202 processwas effective for trace NBdegradation inwater. Gas chromatography-mass spectrometry analysis indicated that a hydroxyl radical addition reaction anddehydrogenation reaction enhanced NBdegradation.

关键词： microwave granular activated carbon hydrogen peroxide nitrobenzene hydroxyl radicals

Occurrence, Structure and Mineral Phases of Nanoparticles in an Anthrosol

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Pedosphere 2013年第3期23卷 273-280页

作者： LU sheng-Gao SUN Fang-Fang ZONG Yu-Tong Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition College of Environmental and Resource Sciences Zhejiang University Key Laboratory of Environment Remediation and Ecological Health Ministry of Education College of Environmental and Resource Sciences Zhejiang University

Soils contain various kinds of crystalline to amorphous solid particles with at least one dimension in the nanoscale （〈 100 nm）. These nanoparticles contribute greatly to dynamic soil processes such as soil genesis, trace element cycling, contaminant transport, and chemical reaction. The nano-sized fraction of an Anthrosol was obtained to determine the occurrence, chemical composition, structure, and mineral phases of nanoparticles using high-resolution transmission electron microscopy （HRTEM） equipped with an energy-dispersive X-ray spectroscopy. Selected area electron diffraction or the fast Fourier transform of high-resolution images was used in structural characterization of the nanoparticles with HRTEM. Two nanoscale mineral types, i.e., mineral nanoparticles and nanomi- nerals, were observed in the Anthrosol. Mineral nanoparticles in soil included well crystalline aluminumsilicate nanosheets, nanorods, and nanoparticles. Nanosheets with a length of 120-150 nm and a width of about 10-20 nm were identified as chlorite/vermiculite series. The presence of clear lattice fringe spacing in HRTEM image of nanoparticles indicated that mineral nanoparticles had a relatively good crystallinity. The nanomineral ferrihydrite also existed in the Anthrosol. The HRTEM images and the particle size distribution histogram suggested that these ferrihydrite nanoparticles were quite homogeneous, and had a narrow size distribution range （1-7 nm） with a mean diameter of 3.6 4- 1.6 nm. Our HRTEM observation indicated that mineral nanoparticles and nanominerals were common and widely distributed in Anthrosols. HRTEM and selected area diffraction or lattice fringe spacing characterization provided further proofs to the structure of nanoparticles formed in soil.

关键词： energy-dispersive X-ray spectroscopy (EDS) ferrihydrite high-resolution transmission electron microscopy (HRTEM) nanominerals nano-sized fraction

Evaluation of Cloud Top Height Retrievals from China’s Next-Generation Geostationary Meteorological Satellite FY-4A

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Journal of Meteorological Research 2019年第3期33卷 553-562页

作者： Zhonghui tan Shuo MA Xianbin ZHAO Wei YAN Wen LU National University of Defense Technology

To evaluate the validity of cloud top height (CTH) retrievals from FY-4A, the first of China's next-generation geostationary meteorological satellite series, the retrievals are compared to those from Himawari-8, CloudSat, Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), and Moderate Resolution Imaging Spectroradiometer (MODIS) operational products from August to October 2017. Regarding CTHs from CloudSat, CALIPSO, and MODIS as truth, the results show that the performance of FY-4A CTH retrievals is similar to that of Himawari-8. Both FY-4A and Himawari-8 retrieve reasonable CTH values for single-layer clouds, but perform poorly for multi-layer clouds. The mean bias error (MBE) shows that the mean value of FY-4A CTH retrievals is smaller than that of Himawari-8 for single-layer clouds but larger for multi-layer clouds. For ice crystal clouds, both FY-4A and Himawari-8 obtain the underestimated CTHs. However, there is a tendency for FY-4A and Himawari-8 to overestimate the CTH values of CloudSat and CALIPSO mainly for low level liquid water clouds. The temperature inversion near the tops of water clouds may result in an overestimation of CTHs. According to the MBE change with altitude, FY-4A and Himawari-8 overestimate the CTHs mainly for clouds below 3 km, and the overestimation is slightly more apparent in Himawari-8 data than that in FY-4A values. As the cloud optical thickness (COT) increases, the CTH bias of FY-4A CTH retrievals gradually decreases. Two typical cases are analyzed to illustrate the differences between different satellites' CTH retrievals in detail.

关键词： FY-4A Himawari-8 CloudSat Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) Moderate Resolution Imaging Spectroradiometer (MODIS) cloud top height (CTH)

Recent advances in phenothiazine-based dyes for dye-sensitized solar cells

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Chinese Chemical Letters 2016年第8期27卷 1304-1318页

作者： Jun-sheng Luo Zhong-Quan Wan Chun-Yang Jia State Key Laboratory of Electronic Thin Films and Integrated Devices School of Microelectronics and Solid-State ElectronicsUniversity of Electronic Science and Technology of China

Dye-sensitized solar cells（DSSCs） have attracted significant attention as alternatives to conventional silicon-based solar cells owing to their low-cost production,facile fabrication,excellent stability and high power conversion efficiency（PCE）.The dye molecule is one of the key components in DSSCs since it significant influence on the PCE,charge separation,light-harvesting,as well as the device *** various dyes,easily tunable phenothiazine-based dyes hold a large proportion and achieve impressive photovoltaic *** class of dyes not only has superiorly non-planar butterfly structure but also possesses excellent electron donating ability and large π conjugated *** review summarized recent developments in the phenothiazine dyes,including small molecule phenothiazine dyes,polymer phenothiazine dyes and phenothiazine dyes for co-sensitization,especially focused on the developments and design concepts of small molecule phenothiazine dyes,as well as the correlation between molecular structures and the photovoltaic performances.

关键词： Dye-sensitized solar cells Molecular engineering Small molecule phenothiazine dyes Polymer phenothiazine dyes Co-sensitization Power conversion efficiency

One-pot synthesis of Au@Pt star-like nanocrystals and their enhanced electrocatalytic performance for formic acid and ethanol oxidation

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Nano Research 2018年第6期11卷 3222-3232页

作者： Yi Peng Lidong Li Ran Tao Lingyu tan Mengna Qiu Lin Guo Key Laboratory of Bio-lnspired Smart Interfacial Science and Technology of Ministry of Education School of Chemistry and Environment Beihang University Beijing 100191 China Department of Chemistry and Biochemistry University of California 1156 High Street Santa Cruz California 95064 USA

The current bottleneck facing further developments in fuel cells is the lack of durable electrocatalysts with satisfactory activity. In this study, a simple and fast one-pot wet-chemical method is proposed to synthesize novel Au@Pt star-like bimetallic nanocrystals （Au@Pt SLNCs） with a low Pt/Au ratio of 1：4, which show great electrocatalytic properties and outstanding stability toward the electro-oxidation reactions commonly found in fuel cells. The star-like Au core （90±20 nm） is partially coated with 5 nm Pt nanocluster shells, a morphology which creates a large amount of boundaries and edges, thus tuning the surface electronic structure as demonstrated by X-ray photoelectron spectroscopy and CO-stripping measurements. This promotes excellent electrocatalytic performance towards the formic acid oxidation reaction in acidic media and the ethanol oxidation reaction in alkaline media, compared to commercial Pt or Au@Pt triangular nanoprisms, in which the Au core is fully coated by a Pt shell. Au@Pt SLNCs have the highest current density within the dehydrogenation potential range, needing the least potential to achieve a certain current density as well as the highest long-term stability. Because of the small amount of Pt usage, very fast synthesis, excellent electrocatalytic activity and durability, the proposed Au@Pt SLNCs have a promising practical application in fuel cells.

关键词： Au@Pt core-shell nanocrystals electrocatalyst formic acid ethanol oxidation

GMP-quadruplex-based hydrogels stabilized by lanthanide ions

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Science China Chemistry 2018年第5期61卷 604-612页

作者： Jin Zhang Xiaoyang Li Xiuping Sun Aixin Song Yebang tan Jingcheng Hao Key Laboratory of Colloid and Interface Chemistry Ministry of Education Shandong University

This work describes the gelation behaviors and properties of a biological molecule, guanosine 5′-monophosphate disodium salt(GMP), in the presence of trivalent lanthanide ions. Hydrogels composed of GMP-quadruplexes were prepared by adjusting p H,through which the protonation of phosphate group was controlled to tune the interactions between lanthanide ions and *** the p H region of 2–6, the electrostatic interaction between lanthanide ions and phosphate group is hindered and the cation-dipole interaction acts as the main driving force for the formation of G-quadruplexes. All the hydrogels were found consisting of three-dimensional network of the intertwining one-dimensional nanofibers formed by the stacking G-quartets induced by lanthanide ions. A significant fluorescence enhancement of thioflavin T(Th T), a fluorescent molecule, was found to be triggered by the G-quadruplex structures, for which the rotation of chromophoric groups on Th T molecules were prohibited due to the implant into the G-quadruplex structures.

关键词： G-quadruplex hydrogel hydrogen bonding electrostatic interaction ion-dipole interaction fluorescence enhancement

NUMERICAL SIMULATION OF BED TOPOGRAPHY CHANGES INDUCED BY DEEP WATER NAVIGATION CHANNEL PROJECT IN THE YANGTZE ESTUARY

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Journal of Hydrodynamics 2003年第4期15卷 46-53页

作者： ZhangJing-xin LiuHua HeYou-sheng ZhangFu-ran QiDing-man SchoolofCivilEngineeringandMechanics ShanghaiJiaotongUniversityShanghai200030China ResearchCenterofEstuarineandCoastalSciences Shanghai201201China

A study on the mathematical modeling of the two dimensional, time-dependentvariation of bottom topography caused by the spur dikes of the deep water navigation channel projectin the Yangtze estuary is reported. The hydro-dynamic flows are computed using the DELFT3D whichserves as the base of computation of sediment transport and bottom deformation. A model of finesediment transport is developed and implemented in an orthogonal curvilinear coordinate system bythe finite difference method. Using the observed water depth of the North Channel of Yangtze estuaryfrom 2001 to 2002, the model is calibrated and validated to determine the parameters in thesediment model. The computational results of the changes of the bed in the North Channel induced bythe spur dikes coincide with the measured data except the area near the structures.

关键词： tidal flow sediment transport yangtze estuary mathematical model

Theory of gas extraction from coal seams and its use

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Journal of Coal Science & Engineering(China) 2012年第3期18卷 276-279页

作者： FAN Xi-sheng Mine Safety Technology Branch China Coal Research InstituteBeijing 100013China State Key Laboratory of Coal Mining and Clean Utilization(China Coal Research Institute) Beijing 100013China

Gas extraction is one of the main measures of control and use of gas of coal mines. At present, the design method is under the experimental period and do not satisfy the need of practice. In this paper, the theory of gas extraction of coal seams based upon Darcy law was studied. Mathematical model of gas extraction of coal seams was established and two kinds of solv- ing approaches based on computer software and linear approximation were given. The rightness and the validities of the model were examined with a practical example. Results obtained can be used to determine and optimize the parameters related etc.

关键词： coal seam gas gas extraction linear approximation

A Systematic Review of the Definition,Measurement,and Associated Factors of Pandemic Fatigue

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China CDC weekly 2024年第36期6卷 924-933,I0007页

作者： Ruohan Chen Qi tan Bowen Su Shuqi Wang Zhanwei Du WHO Collaborating Center for Infectious Disease Epidemiology and Control School of Public HealthLKS Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Laboratory of Data Discovery for Health Limited Hong Kong Science ParkHong Kong Special Administrative RegionChina Nanjing Tech University Nanjing CityJiangsu ProvinceChina School of Cybersecurity Northwestern Polytechnical UniversityXi’an CityShaanxi ProvinceChina.

The rapid emergence and widespread transmission of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)have prompted governments worldwide to enact policies and measures to manage the virus’s *** interventions have substantially contributed to controlling disease ***,they have also significantly disrupted daily life,leading to increased public fatigue and resistance to sustained control measures,a phenomenon known as pandemic *** develop a comprehensive understanding of pandemic fatigue,this review systematically explores the concept and identifies quantitative indicators for measuring *** reviewed studies on pandemic fatigue across various countries,summarized the contributing factors,and analyzed its impact on personal protective *** findings indicate that the enforcement of health measures significantly influences the onset of pandemic fatigue,while individual perceptions of risk can negatively affect personal protective behaviors,creating a feedback loop with increasing *** results underscore the importance of considering the current severity of the pandemic and individual decisionmaking processes in the implementation of *** our understanding of pandemic fatigue is essential for developing effective policy responses in preparation for future potential epidemics.

关键词： fatigue protective prompt

Using interacting multiple model particle filter to track airborne targets hidden in blind Doppler

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1277-1282页

作者： DU Shi-chuan SHI Zhi-guo ZANG Wei CHEN Kang-sheng Department of Information and Electronie Engineering Zhejiang University Hangzhou 310027 China

In airborne tracking,the blind Doppler makes the target undetectable,resulting in tracking difficulties. In this paper,we studied most possible blind-Doppler cases and summed them up into two types:targets' intentional tangential flying to radar and unintentional flying with large tangential speed. We proposed an interacting multiple model(IMM) particle filter which combines a constant velocity model and an acceleration model to handle maneuvering motions. We compared the IMM particle filter with a previous particle filter solution. Simulation results showed that the IMM particle filter outperforms the method in previous works in terms of tracking accuracy and continuity.

关键词： Interacting multiple model Particle filter Blind Doppler