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Enhancing low-temperature NO_x storage and reduction performance of a Pt-based lean NO_x trap catalyst

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Rare Metals 2019年第1期38卷 81-86页

作者： Tong Wang Li-wei jia Xiu-Ting Wang Gang Wang Fu-Qiang Luo jia-Ming Wang School of Automotive and Traffic Engineering Jiangsu University Wuxi weifu Environmental Catalysts Co. Ltd

Two lean NO_x trap(LNT) catalysts, Pt/BaO/CeO_2 + Al_2O_3 and Pt/BaO/CeO_2-Al_2O_3, were prepared and compared for low-temperature(< 250℃) NO_x storage and reduction performance. The influence of the form of ceria on low-temperature NO_x storage and reduction performance of LNT catalysts was investigated with the focus on NO_x storage capacity, NO_x reduction efficiency during lean/rich cycling, product selectivity and thermal *** coupled plasma-atomic emission spectrometry(ICP-AES), Brunner-Emmet-T eller(BET), H_2-pulse chemisorption and X-ray diffraction(XRD) were conducted to characterize the physical properties of LNT catalysts. NO_x storage capacity and NO_x conversion efficiency were measured to evaluate NO_x storage and reduction performance of LNT catalysts. Pt/BaO/CeO_2-Al_2O_3 catalyst exhibits higher NO_x storage capacity than Pt/BaO/CeO_2 + Al_2O_3 catalyst in the temperature range of 150-250 ℃. Meanwhile, Pt/BaO/CeO_2-Al_2O_3 catalyst shows better NO_x conversion efficiency and N_2 selectivity. XRD results indicate that the thermal stability of CeO_2-Al_2O_3 complex oxide is superior to that of pure CeO_2. H_2-pulse chemisorption results show that Pt/BaO/CeO_2-Al_2O_3 catalyst has higher Pt dispersion than Pt/BaO/CeO_2 + Al_2O_3 catalyst over fresh and aged samples. The improved physical properties of Pt/BaO/CeO_2-Al_2O_3 catalyst are attributed to enhance the NOx storage and reduction performance over Pt/BaO/CeO_2 + Al_2O_3 catalyst.

关键词： NOx storage and reduction Low temperature Ceria Ceria-alumina LNT

Geochronological and geochemical evidence for a Late Ordovician to Silurian arc-back-arc system in the northern Great Xing'an Range,NE China

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Geoscience Frontiers 2021年第1期12卷 131-145页

作者： Bo Liu jia-Fu Chen Bao-Fu Han Jun-Lai Liu jia-wei Li Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Department of GeologySchool of Resources and Civil EngineeringNortheastern UniversityShenyang 110819China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural ResourcesChangchun 130061China State Key Laboratory of Geological Process and Mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China Ministry of Education Key Laboratory of Orogenic Belts and Crustal EvolutionSchool of Earth and Space SciencesPeking UniversityBeijing 100871China

The early Paleozoic tectonic evolution of the Xing'an-Mongolian Orogenic Belt is dominated by two oceanic basins on the northwestern and southeastern sides of the Xing'an Block,i.e.,the Xinlin-Xiguitu Ocean and the Nenjiang ***,the early development of the Nenjiang Ocean remains ***,we present zircon U-Pb geochronology and whole-rock elemental and Sr-Nd isotopic data on the gabbros in the Xinglong area together with andesitic tuffs and basalts in the Duobaoshan ***-ICP-MS zircon U-Pb dating of gabbros and andesitic tuffs yielded crystallization ages of 443-436 Ma and 452-451 Ma,*** Early Silurian Xinglong gabbros show calc-alkaline and E-MORB affinities but they are enriched in LILEs,and depleted in HFSEs,with relatively low U/Th ratios of 0.18-0.36 andεNd(t)values of-1.6 to+*** geochemical features suggest that the gabbros might originate from a mantle wedge modified by pelagic sediment-derived melts,consistent with a back-arc basin *** contrast,the andesitic tuffs are characterized by high MgO(>5 wt.%),Cr(138-200 ppm),and Ni(65-110 ppm)contents,and can be termed as high-Mg *** low Sr/Y ratios of 15.98-17.15 and U/Th values of 0.24-0.25 and moderate(La/Sm)_n values of 3.07-3.26 are similar to those from the Setouchi Volcanic Belt(SW Japan),and are thought to be derived from partial melting of subducted sediments,and subsequent melt-mantle *** Duobaoshan basalts have high Nb(8.44-10.30 ppm)and TiO2 contents(1.17-1.60 wt.%),typical of Nb-enriched *** are slightly younger than regional adakitic rocks and have positiveεNd(t)values of+5.2 to+5.7 and are interpreted to be generated by partial melting of a depleted mantle source metasomatized by earlier adakitic *** with coeval arc-related igneous rocks from the southeastern Xing'an Block,we propose that the Duobaoshan high-Mg andesitic tuffs and Nbenriched basalts are parts of the Late Ordovician and Silurian Sonid Zuoqi-Duoba

关键词： Nenjiang ocean Arc-back-arc system Xing'an-Mongolian orogenic belt Gabbros Nb-enriched basalts

Measuring nanoparticles in liquid with attogram resolution using a microfabricated glass suspended microchannel resonator

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Microsystems & Nanoengineering 2022年第4期8卷 261-270页

作者： Mehdi Mollaie Daryani Tomás Manzaneque jia wei Murali Krishna Ghatkesar Department of Precision and Microsystems Engineering Delft University of TechnologyDelftThe Netherlands Department of Microelectronics Delft University of TechnologyDelftThe Netherlands Present address:Department of Microelectronics Delft University of TechnologyDelftThe Netherlands

The use of nanoparticles has been growing in various industrial fields,and concerns about their effects on health and the environment have been ***,characterization techniques for nanoparticles are ***,we present a silicon dioxide microfabricated suspended microchannel resonator(SMR)to measure the mass and concentration of nanoparticles in a liquid as they *** measured the mass detection limits of the device using laser Doppler *** limit reached a minimum of 377 ag that correspond to a 34 nm diameter gold nanoparticle or a 243 nm diameter polystyrene particle,when sampled every 30 *** compared the fundamental limits of the measured data with an ideal noiseless measurement of the ***,we measured the buoyant mass of gold nanoparticles in real-time as they flowed through the SMR.

关键词： resonator suspended nanoparticles

Paclitaxel Prodrug Nanomedicine for Potential CT-imaging Guided Breast Cancer Therapy

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Chinese Journal of Polymer Science 2023年第11期41卷 1747-1759,I0008页

作者： jia-wei Chen Yi Shen Qing-Song Yu Zhi-Hua Gan State Key Laboratory of Organic-Inorganic Composite Materials Beijing Laboratory of Biomedical MaterialsBeijing Advanced Innovation Center for Soft Matter Science and EngineeringCollege of Life Science and TechnologyBeijing University of Chemical TechnologyBeijing 100029China

Nanotheranostics,which combine the therapeutic and diagnostic functions in one integrated system,have received extensive attentions in cancer treatments because they enable non-invasive diagnosis,tumor-targeted drug delivery,and real-time monitoring of therapeutic ***,due to the high systemic toxicity of commonly used chemotherapeutics,current treatment still has ***,to simultaneously achieve safe cancer therapy and therapeutic response monitoring,an iodinated prodrug strategy was proposed.2,3,5-Triiodobenzoic acid(TIBA)was used to modify both paclitaxel(PTX)and the polymeric vehicle,so that the encapsulation efficiency of PTX could be increased and the systemic toxicity could be ***-prepared prodrug nanoparticles could accumulate passively in the tumor site and promptly release loaded drugs in response to the overexpressed GSH in cancer cells,which then caused efficient cell cycle arrest and apoptosis like that of the parent *** this rational design,safe and efficient antitumor therapy and real-time computer tomography(CT)imaging could be simultaneously realized,facilitating potential CT imaging-guided therapy of metastatic breast cancer.

关键词： CT imaging Paclitaxel Prodrug GSH responsiveness Polymeric nanoparticles

Density-Functional Theories for Polyelectrolyte Systems

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Chinese Journal of Polymer Science 2024年第9期42卷 1302-1312,I0006页

作者： jia-wei Zhang Yu-Hang Zhang Bao-Hui Li Qiang Wang School of Physics Nankai UniversityTianjin90001China Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Polymer density-functional theories(PDFTs)have distinct advantages in the study of polyelectrolyte(PE)systems over experiments and molecular *** we give an introductory review of some PDFTs recently developed for PE *** start with a general formalism of PDFTs and its relation to the widely used polymer self-consistent field theory(SCFT),then explain the various correlations that are neglected in SCFT but can be accounted for in PDFTs,including those due to the excluded-volume interaction and chain connectivity of uncharged polymers,the electrostatic correlations of small ions,and the chain correlations in *** also list some applications of PDFTs for PE systems,and finally give some perspectives on future *** hope that our review can attract more researchers to apply and further develop PDFTs as a promising class of theoretical and computational tools.

关键词： Polymer density-functional theories Polyelectrolytes Correlations

A Performance Evaluation of Classic Convolutional Neural Networks for 2D and 3D Palmprint and Palm Vein Recognition

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International Journal of Automation and computing 2021年第1期18卷 18-44页

作者： wei jia jian Gao wei Xia Yang Zhao Hai Min Jing-Ting Lu School of Computer Science and Information Engineering Hefei University of TechnologyHefei 230009China Anhui Province Key Laboratory of Industry Safety and Emergency Technology Hefei 230009China Institution of Industry and Equipment Technology Hefei University of TechnologyHefei 230009China

Palmprint recognition and palm vein recognition are two emerging biometrics *** the past two decades,many traditional methods have been proposed for palmprint recognition and palm vein recognition,and have achieved impressive ***,the research on deep learningbased palmprint recognition and palm vein recognition is still very *** this paper,in order to investigate the problem of deep learning based 2D and 3D palmprint recognition and palm vein recognition indepth,we conduct performance evaluation of seventeen representative and classic convolutional neural networks(CNNs)on one 3D palmprint database,five 2D palmprint databases and two palm vein databases.A lot of experiments have been carried out in the conditions of different network structures,different learning rates,and different numbers of network *** have also conducted experiments on both separate data mode and mixed data *** results show that these classic CNNs can achieve promising recognition results,and the recognition performance of recently proposed CNNs is ***,among classic CNNs,one of the recently proposed classic CNNs,i.e.,EfficientNet achieves the best recognition ***,the recognition performance of classic CNNs is still slightly worse than that of some traditional recognition methods.

关键词： Performance evaluation convolutional neural network(CNN) biometrics palmprint palm vein deep learning

Real-time localization for underwater equipment using an extremely low frequency electric field

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Defence Technology（防务技术） 2023年第8期26卷 203-212页

作者： jia-wei Zhang Peng Yu Run-xiang jiang Tao-tao Xie College of Weapon Engineering Naval University of EngineeringWuhan430033China Weaponry Department Naval Petty Officer AcademyBengbu233012China College of Electric Engineering Naval University of EngineeringWuhan430033China

A new real-time underwater equipment location method adopting an electric field induced by a standard current source is *** goals were real-time tracking and location of stationary or moving underwater equipment both in shallow and deep seas,under noisy *** main features of this method are as follows:(1)a standard current source on the water surface,which can be towed by a vehicle,consisting of two electrodes,a signal generator,and a GPS unit;(2)measurement of the extremely low frequency(ELF)electric field emitted by the current source,made possible by electric field sensors on the underwater equipment;(3)position of the underwater equipment is estimated in real time based on a progressive update extended Kalman filter(PUEKF),which is carried out using the propagation model of an ELF electric field because the electric field at the position of the underwater equipment and the current source position are *** verified the accuracy of our method and confirmed real-time location feasibility through numerical,physical scale,and real-time sea *** numerical experiments,we verified that our method works for underwater equipment location in real-world conditions,and the location error can be less than 0.2 ***,real-time location experiments for stationary underwater measuring equipment in water tank were *** result shows that the location error can be less than 0.1 *** also confirmed real-time location feasibility through the use of offshore *** expect that our method will complement conventional underwater acoustic location methods for underwater equipment in acoustically noisy environments.

关键词： Termsd Real-time tracking and location method Underwater equipment location ELF electric field Shallow sea Physical scale experiment Sea experiment

Effects of synthetic conditions on the structure and morphology of open-ended vanadium oxide nanotubes and study of their growth mechanism

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Chinese Science Bulletin 2007年第14期52卷 1920-1924页

作者： wei jia ZHU Ying ZHANG JingChang Institute of Modern Catalysis Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing University of Chemical Technology Beijing 100029 China Center of Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Vanadium oxide nanotubes (VOx-NTs) have been synthesized by using n-butylamine as structuredirecting template and V2O5 as precursor under hydrothermal conditions. XRD, FTIR, SEM, TEM, BET and TG-DTA characterizations have been performed to both optimize the synthetic conditions and understand the growth mechanism of VOx-NTs. The results showed that open-ended VOx-NTs were obtained under the optimized conditions (hydrothermal temperature: 150―160°C, hydrothermal time: 5―7 d, the molar ratio of V2O5 to n-butylamine is 1:1) with diameters ranging from about 30 to 100 nm and several micrometers in length. The BET surface area and the desorption cumulative pore volume of pores of the as-synthesized sample were about 27.4609 m2/g and 0.191087 cm3/g, respectively. The result presents that the synthesis of VOx-NTs is controlled by the "rolling" mechanism and temperature is primary driving force for rolling.

关键词：钒水热作用生长机制合成条件

Deriving Energy-Level Gap of a System in Presence of a Kerr-like Medium by Virtue of Invariant Eigen-operator Method

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Communications in Theoretical Physics 2006年第4期45卷 614-616页

作者： GUI wei-Jun GUI jia-Zhang TANG Gang Department of Machinery and Electronic Engineering Nanchang institute of Technology Nanchang 330099 China

In this paper, we find the invariant eigen-operators （IEOs） and the energy-level gap of a system with a two-level atom interacting with single mode cavity field through multi-photon transition in the presence of a Kerr-like medium. From this work, one can see that the IEO method in many eases is simpler and easier on obtaining the energy-level gap formula than the usual way.

关键词： energy-level gap Kerr-like medium invariant eigen-operator