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Frontiers of Environmental Science & Engineering 2010年第2期4卷 213-220页

作者： Haifeng JIA Nan DONG hongtao ma Department of Environmental Sciences&Engineering Tsinghua UniversityBeijing 100084China

An index system for evaluation of technologies for urban river rehabilitation was proposed and *** index system includes indicators of cost,resources,environmental improvement,and social *** calculation method for an objective value of each index based on its attributes and weights was *** Foshan Channel,which is a seriously polluted,black and malodorous urban river in Foshan City,China,was selected as a case *** values of the attributes and the weights of the indices for the Foshan Channel were *** technologies for the rehabilitation of the Foshan Channel were evaluated based on this index ***,a rehabilitation scheme for the Foshan Channel was proposed.

关键词： river rehabilitation urban rivers river pollution multi-objective analysis the Foshan Channel

Comparison of the activities of binder-added and binder-free Mo/HZSM-5 catalysts in methane dehydroaromatization at 1073 K in periodic CH_4-H_2 switch operation mode

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Journal of Natural Gas Chemistry 2012年第6期21卷 729-744页

作者： Yuebing Xu hongtao ma Yo Yamamoto Yoshizo Suzuki Zhanguo Zhang National Institute of Advanced Industrial Science and Technology (AIST) 16-10nogawa Tsukuba 305-8569 Japan Meidensha Co. Osaki 2-8-1 Shinagawa-ku Tokyo141-8565 Japan

Three industry-supplied, well-shaped Mo/HZSM-5 catalysts, two binder-added and one binder-free, were tested for the first time in methane dehydroaromatization to benzene at 1073 K and 10000 mL/（g·h） in periodic CH4-H2 switch operation mode, and their catalytic performances were compared with those of three self-prepared, binder-free powder Mo/HZSM-5 catalysts. XRD, 27Al NMR, SEM, BET and NH3-TPD characterizations of all the catalysts show that the zeolites in the two binder-added catalysts are comparable to those in the three binder-free powder catalysts in crystallinity, crystal size, micropore volume and Br{／o}nsted acidity. The test results, on the other hand, show that the catalytic performances of the two binder-added catalysts are worse than those of the four binder-free catalysts on both catalyst mass and zeolite mass bases. Then, TPO and BET measurements of all spent samples were conducted to get a deep insight into the negative effects of binder addition, and the results suggest that the binder additives functioned mainly to enhance the polyaromatization of formed aromatics to coke on their external surfaces and consequently lower the catalysts＇ benzene formation activity and selectivity.

关键词： methane dehydroaromatization Mo/HZSM-5 binder coke formation

Crack Segmentation Based on Fusing Multi-Scale Wavelet and Spatial-Channel Attention

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Structural Durability & Health Monitoring 2023年第1期17卷 1-22页

作者： Peng Geng Ji Lu hongtao ma Guiyi Yang School of Information Sciences and Technology Shijiazhuang Tiedao UniversityShijiazhuang050043China

Accurate and reliable crack segmentation is a challenge and meaningful *** this article,aiming at the characteristics of cracks on the concrete images,the intensity frequency information of source images which is obtained by Discrete Wavelet Transform(DWT)is fed into deep learning-based networks to enhance the ability of network on crack *** well integrate frequency information into network an effective and novel DWTA module based on the DWT and scSE attention mechanism is *** semantic information of cracks is enhanced and the irrelevant information is suppressed by DWTA *** the gap between frequency information and convolution information from network is balanced by DWTA module which can well fuse wavelet information into image segmentation *** Unet-DWTA is proposed to preserved the information of crack boundary and thin crack in intermediate feature maps by adding DWTA module in the encoderdecoder *** decoder,diverse level feature maps are fused to capture the information of crack boundary and the abstract semantic information which is beneficial to crack pixel *** proposed method is verified on three classic datasets including CrackDataset,CrackForest,and DeepCrack *** with the other crack methods,the proposed Unet-DWTA shows better performance based on the evaluation of the subjective analysis and objective metrics about image semantic segmentation.

关键词： Attention mechanism crack segmentation convolutional neural networks discrete wavelet transform

Structure and Mechanical Performance of Nitrogen Doped Diamond-like Carbon Films

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Journal of materials Science & Technology 2007年第4期23卷 491-494页

作者： Huayu ZHANG Liang-xue LIU Yulei WANG hongtao ma Fanxin LIU Harbin Institute of Technology Shenzhen Graduate School Shenzhen518055 China SAE Technologies Development （Dongguan） Co. Ltd. Dongguan 523087 China

Nitrogen doped diamond-like carbon （DLC：N） films were prepared by electron cyclotron resonance chemical vapor deposition （ECR-CVD） on polycrystalline Si chips. Film thickness is about 50 nm. Auger electron spectroscopy （AES） was used to evaluate nitrogen content, and increasing N2 flow improved N content from 0 to 7.6%. Raman and X-ray photoelectron spectroscopy （XPS） analysis results reveal CN-sp^3C and N-sp^2C structure. With increasing the N2 flow, sp^3C decreases from 73.74% down to 42.66%, and so does N-sp^3C from 68.04% down to 20.23%. The hardness decreases from 29.18 GPa down to 19.74 GPa, and the Young＇s modulus from 193.03 GPa down to 144.52 GPa.

关键词： Nitrogen doped diamond-like carbon films ECR-CVD Structure Mechanical performance

Effect of thickness on structures of ultrathin diamond-like carbon films

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Chinese Science Bulletin 2010年第18期55卷 1949-1951页

作者： CHE XiaoZhou CHEN LianHua ma hongtao FANG HongXin College of materials Science & Engineering South China University of Technology Guangzhou 510640 China SAE Dongguan 523087 China

Diamond-like carbon(DLC) films with different thickness were deposited by filtered cathode vacuum arc(FCVA).Vis-Raman and spectroscopic ellipsometry were employed to analyze the structure of DLC *** wavelength of Vis-Raman is 514.5 *** results show that structures of DLC films are affected by film *** the film thickness increases from 2 to 30 nm,the G-peak position(G-pos) shifts to higher wavelength,the intensity ratio ID/IG and the extinction coefficient Ks *** is indicated that the content of sp3 bond increases with film ***,when the film thickness increases from 30 nm to 50 nm,ID/IG and Ks *** content of sp3 bonds decreases with film thickness.

关键词：类金刚石碳薄膜薄膜厚度结构过滤阴极真空电弧类金刚石薄膜超薄拉曼光谱 FCVA

Chemical Stability, Ionic Conductivity of BaCe0.9-xZrxSm0.10O3-α and Its Application to Ammonia Synthesis at Atmospheric Pressure

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Chinese Journal of Chemistry 2011年第6期29卷 1114-1118页

作者： Wang, Xiaowen Yin, Jinling XU, Jianhong Wang, hongtao ma, Guilin Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou Jiangsu 215123 China

Dense ceramic samples BaCe0.9-xZrxSm0.10O3-α （x=0.10, 0.15, 0.20, 0.30） were obtained by heat-treating the precursors prepared from a coprecipitation route. The phase structure, chemical stability and conduction behaviors of the ceramic samples have been investigated by X-ray powder diffraction and alternating current impedance spectroscopy methods. All the ceramic samples displayed a single phase of orthorhombic perovskite. The samples with x ≥0.20 were relatively stable after exposed to the flowing mixed gases： CO2 （φ=3%）＋H2O （φ=3%）＋N2 （φ= 94%） at 873 K for 12 h. Among the samples tested, the sample with x=0.20 exhibited both adequate conductivity and better chemical stability. The contribution of different charged species for x=0.20 sample to the conduction in wet hydrogen atmosphere was investigated by means of gas concentration cells. It was found that the sample of x= 0.20 was almost a pure ionic conductor, and the ionic conduction was contributed mainly by proton and partially by oxide ion in wet hydrogen atmosphere at 773--1073 K. The ammonia synthesis at atmospheric pressure in an electrolytic cell based on the sample of x=0.20 was successfully conducted and the peak ammonia formation rate achieved 2.67 × 10 ^-9 molos-locm 2 with direct current of 0.80 ma at 773 K.

关键词： BaCe0.9-xZrxSm0.10O3-α chemical stability ion conduction proton transport ammonia synthesis

Electrocatalytic debromination of BDE-47 at palladized graphene electrode

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Frontiers of Environmental Science & Engineering 2014年第2期8卷 180-187页

作者： hongtao YU Bin ma Shuo CHEN Qian ZHAO Xie QUAN Shahzad AFZAL School of Environmental Science and Technology Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) Dalian University of Technology Dalian 116024 China

Graphene electrodes （Ti/Gr） were prepared by depositing Gr sheets on Ti substrate, followed by an annealing process for enhancing the adhesion strength. Electrochemical impedance spectroscopies and X-ray dif- fraction patterns displayed that the electrochemical behavior of Ti/Gr electrodes can be improved due to the generation of TiO2 layer at Ti-Gr interface during the annealing process. The palladized Gr electrodes （Ti/Gr/Pd） were prepared by electrochemical depositing Pd nanoparticles on Gr sheets. The debromination ability of Ti/Gr/Pd electrodes was investigated using BDE-47 as a target pollutant with various bias potentials. The results indicated that the BDE-47 degradation rates on Ti/Gr/Pd electrodes increased with the negative bias potentials from 0V to -0.5 V （vs. SCE）. Almost all of the BDE-47 was removed in the debromination reaction on the Ti/Gr/Pd electrode at - 0.5 V for 3 h, and the main product was diphenyl ethers, meaning it is promising to debrominate completely using the Ti/Gr/Pd electrode. Although the debromination rate was slightly slower at -0.3 V than that under -0.5 V, the current efficiency at -0.3 V was higher, because the electrical current acted mostly on BDE-47 rather than on water.

关键词： graphene palladium debromination BDE- 47

Neural Network Robust Control Based on Computed Torque for Lower Limb Exoskeleton

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 83-99页

作者： Yibo Han hongtao ma Yapeng Wang Di Shi Yanggang Feng Xianzhong Li Yanjun Shi Xilun Ding Wuxiang Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beihang Goer(WeiFang)Intelligent Robot Co. Ltd.Beihang UniversityWeifangChina Research Center of Satellite Technology Harbin Institute of TechnologyHarbinChina Beijing Xinfeng Aerospace Equipment Co. LtdBeijingChina

The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial *** modeling errors of the exoskeleton in different application scenarios pose challenges to the robustness and stability of its control *** Radial Basis Function(RBF)neural network is used widely to compensate for modeling *** order to solve the problem that the current RBF neural network controllers cannot guarantee the asymptotic stability,a neural network robust control algorithm based on computed torque method is proposed in this paper,focusing on trajectory *** innovatively incorporates the robust adaptive term while introducing the RBF neural network term,improving the compensation ability for modeling *** stability of the algorithm is proved by Lyapunov method,and the effectiveness of the robust adaptive term is verified by the *** wearing the exoskeleton under different walking speeds and scenarios were carried out,and the results show that the absolute value of tracking errors of the hip and knee joints of the exoskeleton are consistently less than 1.5°and 2.5°,*** proposed control algorithm effectively compensates for modeling errors and exhibits high robustness.

关键词： Lower limb exoskeleton Model compensation RBF neural network Computed torque method

Development of highly active coated monolith SCR catalyst with strong abrasion resistance for low-temperature application

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Frontiers of Environmental Science & Engineering 2015年第6期9卷 979-987页

作者： Lina GAN Shan LEI Jian YU hongtao ma Yo YAmaMOTO Yoshizo SUZUKI Guangwen XU Zhanguo ZHANG State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China materials Research Department Materials Research Laboratories Research and Development Group Meidensha Corporation 8-1 Osaki 2-Chome Shinagawa-ku Tokyo 141-8565 Japan National Institute of Advanced Industrial Science and Technology (AIST) Onogawa 16-1 Tsukuba 305-8569 Japan

Monolith SCR catalysts coated with V2Os- WO3/TiO2 were prepared by varying binder and coating thickness. Comparing with a monolith extruded with 100% V2O5-WO3/TiO2 powder, a coated monolith with a catalyst-coating layer of 260 μm in thickness exhibited the similar initial NOx reduction activity at 250℃. After 4 h abrasion （attrition） in an air stream containing 300 g. m^-3 fine sands （50-100μm） at a superficial gas velocity of 10m·s^-1, the catalyst still has the activity as a 100% molded monolith does in a 24-h activity test and it retains about 92% of its initial activity at 250℃. Estimation of the equivalent durable hours at a fly ash concentration of 1.0 g.m^-3 in flue gas and a gas velocity of 5 m.s^-1 demonstrated that this coated monolith catalyst is capable of resisting abrasion for 13 months without losing more than 8% of its initial activity. The result suggests the great potential of the coated monolith for application to de-NOx of flue gases with low fly ash concentrations from, such as glass and ceramics manufacturing processes.

关键词： coated monolith low-temperature denitration,abrasion resistance attrition

Development of catalysts for direct non-oxidative methane aromatization

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Resources Chemicals and materials 2022年第1期1卷 80-92页

作者： Yuji Ogawa Yuebing Xu Zhanguo Zhang hongtao ma Yo Yamamoto materials Research Department Advanced Technology Research LaboratoriesResearch&Development GroupMeidensha Corporation515Kaminakamizo HigashimakadoNumazu-shiShizuoka 410-8588Japan Department of Chemical Engineering School of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Key Laboratory on Resources Chemicals and materials of Ministry of Education Shenyang University of Chemical TechnologyShenyang 110142China Research&Development Planning and Administration Division Research&Development GroupMeidensha CorporationOsaki 2-8-1Shinagawa-kuTokyo 141-8565Japan

Direct catalytic conversion of methane to benzene at non-oxidative condition is considered as one of key reac-tions for constitution of sustainable carbon-cycling processes,since either biomethane or CO_(2)-based synthetic methane can serve as its feed *** this concern may motivate many researchers over the world to make their continuous effort to gain deep insight into the catalytic mechanism of this catalysis system and the essential cause of the catalyst deactivation,successful development of a catalyst with high performance,enhanced coking resistance and long-term operating stability will be the key to its industrial *** in this review pa-per,we demonstrate the high catalytic activity and stability of our two shaped Mo/HZSM-5 catalysts developed respectively for fixed-bed and fluidized-bed operations at severe reaction ***,a pos-sibly high aromatization temperature is required to attain a desired high benzene formation rate,but adopting such a temperature will certainly accelerate coke formation and catalyst ***,the focus of the catalyst development was laid on finding various effective ways of suppressing coke accumulation and catalyst deactivation at practically required severe reaction conditions,and much effort was made to attain the *** a result,a highly active and selective pelleted Mo/HZSM-5 catalyst has been successfully developed and was stably run in a fixed-bed reactor under cyclic regeneration operation mode over 1000 *** parallel a binder-free,fluidizable Mo/HZSM-5 catalyst with certain mechanical strength has also been developed and successfully tested in a dual circulating fluidized-bed reactor system to provide a stable benzene yield of about 12%at 1073 K and 3000 ml/g/h space velocity.

关键词： Methane dehydroaromatization Methane to benzene(MTB)Mo/HZSM-5 catalyst development Fixed-bed reactor Fluidized-bed reactor