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Reaction Kinetics of LiOH Improved with Composite Silica Gel of Lanthanum Chloride for Absorbing CO_2

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Journal of Rare Earths 2007年第S2期25卷 143-147页

作者：赵卓傅平丰王敬欣 Department of Environmental Science College of Arts & Science of Beijing Union University research Institute of Indoor Environment Beijing Union University research Institute of Science and {1. information Beijing General Institute for Nonferrous Metals

A static method was employed to study the reaction kinetics of anhydrous lithium hydroxide (LiOH) and CO2. The reaction generated water was absorbed with the composite silica gel of lanthanum chloride to make the experiment repeatable. At the reaction temperature of 1.～60 ℃ and initial CO2 pressures of 25～1.0 kPa, the reaction rate of anhydrous LiOH and CO2 decreased slightly with the reduction of initial CO2 pressure and the rise of reaction temperature, indicating that the reaction activation energy of LiOH and CO2 was negative and close to zero. During the middle period (1.5 min) of the isothermal reaction, the ratio of reaction efficiency was approximately the power of 0.4 to that of initial CO2 pressures. As anhydrous LiOH reacted to CO2, the solid product Li2CO3 covered on the surface of LiOH was not compact, so it did not hinder the subsequent reaction of absorbing the CO2 gas. The reaction kinetics of anhydrous LiOH and CO2 obeyed the Erofeev′s model.

关键词： lanthanum chloride anhydrous lithium hydroxide carbon dioxide kinetics

Delonix regia and Casuarina equisetifolia as passive biomonitors and as bioaccumulators of atmospheric trace metals

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Journal of Environmental Sciences 2010年第7期22卷 1073-1079页

作者： Emmanuel Ehiabhi Ukpebor Justina Ebehirieme Ukpebor Emmanuel Aigbokhan Idris Goji Alex Okiemute Onojeghuo Anthony Chinedum Okonkwo Air Pollution research Group Department of ChemistryUniversity of Benin Lancaster Environment centre Lancaster University Department of Botany University of Benin Federal Ministry of Environment and Housing

The suitability of two common and ubiquitously distributed and exotic ornamental plant species in Nigeria-Delonix regia and Casuarina equisetifolia as biomonitors and as effective bioaccumulators of atmospheric trace metals （Cd, Pb, Zn and Cu） has been evaluated. Bark and leaf samples from these plant species were collected in June and July 2006 at five locations in Benin City. Four of the sampling sites were in areas of high traffic density and commercial activities, the fifth site is a remote site, selected to act as a control and also to provide background information for the metals. The plant samples were collected and processed using standard procedures and trace metals were determined using atomic absorption spectrometer. The bark of the plants was able to bioaccumulate the trace metals, especially Pb which originates from anthropogenic contributions in the city. The Pb range of 20.00-70.00 μg/g measured for the bark samples ofD. regia, exceeded the normal plant Pb concentration of 0.2-20.0 μg/g and most Pb data available in literature. The bark of the plants was observed to accumulate more metals compared to the leave, while D. regia was found to be slightly better than C. equisetifolia in trace metal uptake efficiency. {1. variations in the distributions of Pb and Zn were significant （p 〈 0.05）, and the continuous use of leaded fuel in Nigeria was identified as the predominant source of Pb in the atmosphere.

关键词： passive biomonitors trace metals Delonix regia Casuarina equisetifolia

End-to-End Joint Multi-Object Detection and Tracking for Intelligent Transportation Systems

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 280-290页

作者： Qing Xu Xuewu Lin Mengchi Cai Yu‑ang Guo Chuang Zhang Kai Li Keqiang Li Jianqiang Wang Dongpu Cao School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China Horizon information {1. Co. Ltd.Beijing 100096China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Dongfeng USharing technology Co. Ltd.Wuhan 430000China Department of Mechanical and Mechatronics Engineering University of WaterlooWaterlooON N2L 3G1Canada

Environment perception is one of the most critical technology of intelligent transportation systems(ITS).Motion interaction between multiple vehicles in ITS makes it important to perform multi-object tracking(MOT).However,most existing MOT algorithms follow the tracking-by-detection framework,which separates detection and tracking into two independent segments and limit the global ***,a few algorithms have combined feature extraction into one network;however,the tracking portion continues to rely on data association,and requires com‑plex post-processing for life cycle *** methods do not combine detection and tracking *** paper presents a novel network to realize joint multi-object detection and tracking in an end-to-end manner for ITS,named as global correlation network(GCNet).Unlike most object detection methods,GCNet introduces a global correlation layer for regression of absolute size and coordinates of bounding boxes,instead of ofsetting *** pipeline of detection and tracking in GCNet is conceptually simple,and does not require compli‑cated tracking strategies such as non-maximum suppression and data *** was evaluated on a multivehicle tracking dataset,UA-DETRAC,demonstrating promising performance compared to state-of-the-art detectors and trackers.

关键词： Intelligent transportation systems Joint detection and tracking Global correlation network End-to-end tracking

Molybdenum sulfide/graphene-carbon nanotube nanocomposite material for electrocatalytic applications in hydrogen evolution reactions

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Nano research 2016年第3期9卷 837-848页

作者： Majid Khan Ammar Bin Yousaf Mingming Chen Chengsha Wei Xibo Wu Ningdong Huang Zemin Qi Liangbin Li National Synchrotron Radiation Laboratory and School of Nuclear Science and technology CAS Key Laboratory of Soft Matter Chemistry University of Science and Technology of China Hefei 230029 China Department of Computer Science and IT Sarhad University of Science and Information Technology Peshawar 25000 Pakistan Hefei National Laboratory for Physical Sciences at Microscale School of Chemistry and Materials Science University of Science and Technology of China Hefei 230026 China

We report a three-dimensional hierarchical ternary hybrid composite of molybdenum disulfide （MoS2）, reduced graphene oxide （GO）, and carbon nano- tubes （CNTs） prepared by a two-step process. Firstly, reduced GO-CNT composites with three-dimensional microstructuresare synthesized by hydrothermal treatment of an aqueous dispersion of GO and CNTs to form a composite structure via π-π interactions. Then, MoS2 nanoparticles are hydrothermally grown on the surfaces of the GO-CNT composite. This ternary composite shows superior electrocatalytic activity and stability in the hydrogen evolution reaction, with a low onset potential of only 35 mV, a Tafel slope of -38 ***-1.and an apparent exchange current density of 74.25 ***-2. The superior hydrogen evolution activity stemmed from the synergistic effect of MoS2 with its electrocatalytically active edge-sites and excellent electrical coupling to the underlying graphene and CNT network.

关键词： 3D nanostructure MoS2 graphene carbon nanotubes hydrogen evolutionreaction

V_2O_5·nH_2O nanosheets and multi-walled carbon nanotube composite as a negative electrode for sodium-ion batteries

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Journal of Energy Chemistry 2019年第3期28卷 145-151页

作者： Ahmed S. Etman Junliang Sun Reza Younesi Department of Materials and Environmental Chemistry (MMK) Stockholm University Department of Chemistry Faculty of science Alexandria University College of Chemistry and Molecular Engineering Peking University ?ngstr?m advanced Battery {1. Department of Chemistry-?ngstr?m Laboratory Uppsala University

Two dimensional(2D) transition metal oxides and chalcogenides demonstrate a promising performance in sodium-ion batteries(SIBs) application. In this study, we investigated the use of a composite of freeze dried V_2O_5·nH_2O nanosheets and multi-walled carbon nanotube(MWCNT) as a negative electrode material for SIBs. Cyclic voltammetry(CV) results indicated that a reversible sodium-ion insertion/deinsertion into the composite electrode can be obtained in the potential window of 0.1.2.5 V vs. Na^+/Na. The composite electrodes delivered sodium storage capacities of 1.0 and 45 m Ah g^(-1. under applied current densities of 20 and 1.0 m A g^(-1., respectively. The pause test during constant current measurement showed a raise in the open circuit potential(OCP) of about 0.46 V, and a charge capacity loss of ～1.%. These values are comparable with those reported for hard carbon electrodes. For comparison, electrodes of freeze dried V_2O_5·nH_2O nanosheets were prepared and tested for SIBs application. The results showed that the MWCNT plays a significant role in the electrochemical performance of the composite material.

关键词： Sodium-ion batteries Anode materials Vanadium pentoxide nanosheets Composite materials

Effects of bicarbonate and cathode potential on hydrogen production in a biocathode electrolysis cell

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Frontiers of Environmental Science & Engineering 2014年第4期8卷 624-630页

作者： Dawei LIANG Yanyan LIU Sikan PENG Fei LAN Shanfu LU Yan XIANG Key Laboratory of Bio-lnspired Smart Interfacial Science and technology of Ministry of Education School of Chemistry & Environment Beihang University Beijing 100191 China Beijing Key Laboratory for advanced Functional Materials and Thin Fihn {1. Beihang University Beijing 100191 China

A biocathode with microbial catalyst in place of a noble metal was successfully developed for hydrogen evolution in a microbial electrolysis cell （MEC）. The strategy for fast biocathode cultivation was demonstrated. An exoelectrogenic reaction was initially extended with an H2-full atmosphere to enrich Ha-utilizing bacteria in a MEC bioanode. This bioanode was then inversely polarized with an applied voltage in a half-cell to enrich the hydrogen-evolving biocathode. The electrocatalytic hydrogen evolution reaction （HER） kinetics of the biocathode MEC could be enhanced by increasing the bicarbonate buffer concentration from 0.05 mol·L-1.to 0.5 mol· L-1.and/or by decreasing the cathode potential from -0.9 V to - 1.3 V vs. a saturated calomel electrode （SCE）. Within the tested potential region in this study, the HER rate of the biocathode MEC was primarily influenced by the microbial catalytic capability. In addition, increasing bicarbonate concentration enhances the electric migration rate of proton carriers. As a consequence, more mass H＋ can be released to accelerate the biocathode-catalyzed HER rate. A hydrogen production rate of 8.44 m3. m 3. d1.with a current density of 951.6 A. m-3 was obtained using the biocathode MEC under a cathode potential of - 1.3 V vs. SCE and 0.4 mol· L-1.bicarbonate. This study provided information on the optimization of hydrogen production in biocathode MEC and expanded the practical applications thereof.

关键词： microbial electrolysis cell (MEC) biocathode hydrogen production bicarbonate cathode potential

Self-adaptive label filtering learning for unsupervised domain adaptation

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Frontiers of Computer Science 2023年第1期17卷 225-227页

作者： Qing TIAN Heyang SUN Shun PENG Tinghuai MA School of Computer and Software Nanjing University of Information Science and TechnologyNanjing 210044China Engineering research Center of Digital Forensics Ministry of EducationNanjing University of Information Science and TechnologyNanjing 210044China

1.Introduction As an emerging machine learning paradigm,unsupervised domain adaptation(UDA)aims to train an effective model for unlabeled target domain by leveraging knowledge from related but distribution-inconsistent source *** of the existing UDA methods[2]align class-wise distributions resorting to target domain pseudo-labels,for which hard labels may be misguided by misclassifications while soft labels are confusing with trivial noises so that both of them tend to cause frustrating *** overcome such drawbacks,as shown in Fig.1.we propose to achieve UDA by performing self-adaptive label filtering learning(SALFL)from both the statistical and the geometrical perspectives,which filters out the misclassified pseudo-labels to reduce negative ***,the proposed SALFL firstly predicts labels for the target domain instances by graph-based random walking and then filters out those noise labels by self-adaptive learning strategy.

关键词： filtering resort overcome

DCRL-KG: Distributed Multi-Modal Knowledge Graph Retrieval Platform Based on Collaborative Representation Learning

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Intelligent Automation & Soft Computing 2023年第6期36卷 3295-3307页

作者： Leilei Li Yansheng Fu Dongjie Zhu Xiaofang Li Yundong Sun Jianrui Ding Mingrui Wu Ning Cao Russell Higgs Artificial Intelligence Academy Wuxi Vocational College of Science and TechnologyWuxi214068China School of Computer Science and technology Harbin Institute of TechnologyWeihai204209China Department of Mathematics Harbin Institute of TechnologyWeihai264209China College of information Engineering Shandong Vocational and Technical University of International StudiesRizhao276826China School of Mathematics and Statistics University College DublinDublinD04 V1W8Ireland

The knowledge graph with relational abundant information has been widely used as the basic data support for the retrieval *** and text descriptions added to the knowledge graph enrich the node information,which accounts for the advantage of the multi-modal knowledge *** the field of cross-modal retrieval platforms,multi-modal knowledge graphs can help to improve retrieval accuracy and efficiency because of the abundant relational infor-mation provided by knowledge *** representation learning method is sig-nificant to the application of multi-modal knowledge *** paper proposes a distributed collaborative vector retrieval platform(DCRL-KG)using the multi-modal knowledge graph VisualSem as the foundation to achieve efficient and high-precision multimodal data ***,use distributed technology to classify and store the data in the knowledge graph to improve retrieval ***,this paper uses BabelNet to expand the knowledge graph through multi-ple filtering processes and increase the diversification of ***,this paper builds a variety of retrieval models to achieve the fusion of retrieval results through linear combination methods to achieve high-precision language retrieval and image *** paper uses sentence retrieval and image retrieval experi-ments to prove that the platform can optimize the storage structure of the multi-modal knowledge graph and have good performance in multi-modal space.

关键词： Multi-modal retrieval distributed storage knowledge graph

Robust quantum secure direct communication with a quantum one-time pad over a collective-noise channel

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Science China(Physics,Mechanics & Astronomy) 2011年第5期54卷 942-947页

作者： GU Bin ZHANG ChengYi CHENG GuoSheng HUANG YuGai College of Math and Physics Nanjing University of Information Science and Technology Nanjing 210044 China Photonic technology Laboratory Nanjing University of lnformation Science and Technology Nanjing 210044 China School of Math and Physics Queen's University Belfast Belfast BT7 1NN U.K. jiangsu Institute of Education Nanjing 210013 China

We present two robust quantum secure direct communication (QSDC) schemes with a quantum one-time pad over a collective-noise channel. Each logical qubit is made up of two physical qubits and it is invariant over a collective-noise channel. The two photons in each logical qubit can be produced with a practically entangled source, i.e., a parametric down-conversion source with a beta barium borate crystal and a pump pulse of ultraviolet light. The information is encoded on each logical qubit with two logical unitary operations, which will not destroy the antinoise feather of the quantum systems. The receiver Bob can read out the sender's message directly with two single-photon measurements on each logical qubit, instead of Bell-state measurements, which will make these protocols more convenient in a practical application. With current {1., our two robust QSDC schemes are feasible and may be optimal ones.

关键词： quantum secure direct communication quantum one-time pad robust collective noise