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Journal of Environmental Sciences 2024年第11期145卷 128-138页

作者： Xingyu Liu Jingkun chen bowen Han Renna Li Le Shi Zhongbiao Wu Xiaole Weng Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China Zhejiang Provincial Engineering Research Centre of Industrial Boiler&Furnace Flue Gas Pollution Control Hangzhou 310058China

Zeolites are a promising support for Pd catalysts in leanmethane(ch_(4))***,three types of zeolites(H-MOR,H-ZSM-5 and H-Y)were selected to estimate their structural effects and deactivation mechanisms in ch_(4)*** show that variations in zeolite structure and surface acidity led to distinct ch.nges in Pd ***/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity,with activation energy(Ea)at 73 kJ/mol,while Pd/H-ZSM-5 displayed the highest turnover frequency(TOF)at 19.6×10^(−3)sec^(−1),presumably owing to its large particles with more step sites providing active sites in one particle for ch_(4)***/H-Y with dispersed PdO within pore channels and/or Pd2+ions on ion-exch.nge sites yielded the lowest apparent activity and ***,Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition,but introducing 3 vol.%H_(2)O caused the ch_(4)conversion rate on Pd/H-MOR drop from 100%to 63%and that on Pd/H-ZSM-5 decreased remarkably from 82%to 36%.The former was shown to originate fromzeolite structural dealumination,and the latter principally owed to Pd aggregation and the loss of active PdO.

关键词： Methane combustion Pd catalysts Zeolite Structure-performance relationship Deactivation mechanism

Methane and nitrous oxide emissions from municipal wastewater treatment plants in china:A plant-level and technology-specific study

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Environmental Science and Ecotechnology 2024年第4期20卷 123-130页

作者： Haiyan Li Liangfang You He Du bowen Yu Lu Lu Bo Zheng Qiang Zhang Kebin He Nanqi Ren School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen518055China Shenzhen Key Laboratory of Ecological Remediation and Carbon Sequestration Institute of Environment and EcologyTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen518055China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing100084China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China

Wastewater treatment is an important source of greenhouse gases(GHGs).Yet large uncertainties remain in the quantification of GHG emissions from municipal wastewater treatment plants(MWWTPs)in china.A high-resolution and technology-specific emission inventory is still lacking to support mitigation strategies of *** we develop a plant-level and technology-based MWWTP emission inventory for china covering 8703 plants and 19 treatment technology categories by compiling and harmonizing the most up-to-date facility-level ***'s methane(ch_(4))and nitrous oxide(N_(2)O)emissions from MWWTPs in 2020 are estimated to be 150.6 Gg and 22.0 Gg,respectively,with the uncertainty range of-30%to 37%and-30%to 26%at 95%confidence *** find an emission inequality across cities,with the richest cities emitting two times more ch_(4)and N_(2)O per capita from municipal wastewater treatment than the poorest *** emitted ch_(4)and N_(2)O are dominated by Anaerobic/Anoxic/Oxic-,Sequencing Batch Reactor-,Oxidation Ditch-,and Anoxic/Oxic-based MWWTPs of less than 20 years *** the relatively young age structure of china's MWWTPs,the committed emissions highlight the importance of reducing on-site GHG emissions by optimization of operating conditions and innovation *** emission differences among our estimates,previous studies,and the Intergovernmental Panel on Climate ch.nge guidelines are largely attributed to the uncertainties in emission factors,implying the urgent need for more plant-integrated measurements to improve the accuracy of emission accounting.

关键词： Methane Nitrous oxide Emissions Municipal wastewater treatment plants

Preparation of palladium-based catalyst by plasma-assisted atomic layer deposition and its applications in CO_(2) hydrogenation reduction

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Plasma Science and Technology 2024年第6期26卷 31-39页

作者：唐守贤田地李筝王正铎刘博文程久珊刘忠伟 Laboratory of Plasma Physics and Materials Beijing Institute of Graphic CommunicationBeijing 102600People’s Republic of China

Supported Pd catalyst is an important noble metal material in recent years due to its high catalytic performance in CO_(2)hydrogenation.A fluidized-bed plasma assisted atomic layer deposition(FP-ALD) process is reported to fabricate Pd nanoparticle catalyst over γ-Al_(2)O_(3)or Fe_(2)O_(3)/γ-Al_(2)O_(3)support,using palladium hexafluoroacetylacetonate as the Pd precursor and H_(2)plasma as *** transmission electron microscopy exhibits that highdensity Pd nanoparticles are uniformly dispersed over Fe_(2)O_(3)/γ-Al_(2)O_(3)support with an average diameter of 4.4 *** deposited Pd-Fe_(2)O_(3)/γ-Al_(2)O_(3)shows excellent catalytic performance for CO_(2)hydrogenation in a dielectric barrier discharge *** a typical condition of H_(2)to CO_(2)ratio of 4 in the feed gas,the discharge power of 19.6 W,and gas hourly space velocity of10000 h^(-1),the conversion of CO_(2)is as high as 16.3% with ch_(3)OH and ch4selectivities of 26.5%and 3.9%,respectively.

关键词： atomic layer deposition CO_(2)hydrogenation palladium based catalyst

溶胶-凝胶法合成Ti-Fe复合物及其铀(Ⅵ)吸附性能

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硅酸盐学报 2024年第8期52卷 2674-2684页

作者：丁玲张帅郑博文党振华张林中国工程物理研究院激光聚变研究中心靶材科学与制造研究室四川绵阳621900

TiO_(2)基材料以其优异的化学稳定性、光稳定性、无毒性、低成本等优点被广泛应用于铀吸附。虽然TiO_(2)基材料在铀吸附领域有一定的研究,但其铀吸附性能仍不理想。为了提高TiO_(2)基材料对铀(Ⅵ)的吸附能力,本工作采用溶胶凝胶法制备... 详细信息

TiO_(2)基材料以其优异的化学稳定性、光稳定性、无毒性、低成本等优点被广泛应用于铀吸附。虽然TiO_(2)基材料在铀吸附领域有一定的研究,但其铀吸附性能仍不理想。为了提高TiO_(2)基材料对铀(Ⅵ)的吸附能力,本工作采用溶胶凝胶法制备了掺杂铁的纳米TiO_(2)材料(Ti-Fe复合物),并将其用于废水中铀(Ⅵ)的分离。Ti-Fe复合物对铀(Ⅵ)的吸附效率在60 min内达到平衡,吸附效率为94.5%,最大吸附容量为672.9mg/g。等温模型和动力学模型表明,Ti-Fe复合物对铀(Ⅵ)的吸附为单层均匀的化学吸附。通过X射线光电子能谱分析了铀(Ⅵ)与Ti-Fe复合物的相互作用机理,主要包括氧空位填充、氧化还原作用和球内表面络合作用。Ti-Fe复合物有望应用于实际处置含铀(Ⅵ)废水。

关键词：钛-铁复合物吸附铀(Ⅵ) 溶胶-凝胶

血管内皮生长因子对脂多糖诱导的巨噬细胞极化和破骨细胞分化的影响

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中国临床研究 2024年第1期37卷 116-121页

作者：李博文郭春吴大鹏韩博闻李阳阳杨锐娟梁秋冬新乡医学院河南新乡453000 新乡医学院第一附属医院骨外科河南新乡453100

目的探讨血管内皮生长因子(VEGF)对在脂多糖(LPS)诱导下的RAW264.7巨噬细胞表型极化水平及破骨细胞分化的影响。方法将处于对数生长期的RAW264.7细胞分为3组,培养周期为4 d, Control组为正常培养的RAW264.7细胞;LPS组为细胞接种贴壁... 详细信息

目的探讨血管内皮生长因子(VEGF)对在脂多糖(LPS)诱导下的RAW264.7巨噬细胞表型极化水平及破骨细胞分化的影响。方法将处于对数生长期的RAW264.7细胞分为3组,培养周期为4 d, Control组为正常培养的RAW264.7细胞;LPS组为细胞接种贴壁后每次换液同时加入100 ng/mL LPS;LPS+VEGF组加LPS的方法与LPS组相同,第4天换液时加入1μg/mL VEGF。梯度密度培养RAW264.7细胞行甲苯胺蓝染色明确适宜种植密度;显微镜观察各组细胞形态变化;Western blot法检测各组白细胞介素(IL)-12、IL-10、精氨酸-1(Arg-1)蛋白表达水平;流式细胞术荧光标记测定各组巨噬细胞极化水平;抗酒石酸酸性磷酸酶染色检测各组破骨细胞分化水平。结果甲苯胺蓝染色明确细胞种植密度为2.5×10^(3)/cm^(2)。显微镜下观察LPS组出现大量M1型巨噬细胞,LPS+VEGF组出现少量M2型巨噬细胞。LPS+VEGF组IL-12蛋白表达量低于LPS组(P<0.05),IL-10和Arg-1蛋白表达量显著高于LPS组(P<0.05)。LPS+VEGF组F4/80+CD206蛋白阳性表达率高于LPS组(P<0.01),破骨细胞染色阳性计数高于LPS组[(41.83±3.25)个vs(25.67±4.89)个,t=6.154,P<0.01]。结论 VEGF可促进LPS诱导下的RAW264.7细胞向M2表型极化同时促进破骨细胞分化。

关键词：血管内皮生长因子脂多糖 RAW264.7 破骨细胞巨噬细胞极化

Federated Learning with Privacy-preserving and Model IP-right-protection

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Machine Intelligence Research 2023年第1期20卷 19-37页

作者： Qiang Yang Anbu Huang Lixin Fan chee Seng chan Jian Han Lim Kam Woh ng Ding Sheng Ong bowen Li WeBank Shenzhen 518057China Hong Kong University of Science and Technology Hong Kong 999077China University of Malaya Kuala Lumpur 50603Malaysia University of Surrey Guildford GU27XHUK University of Aberystwyth Wales SY233DDUK Shanghai Jiao Tong University Shanghai 200240China

In the past decades,artificial intelligence(AI)has achieved unprecedented success,where statistical models become the central entity in ***,the centralized training and inference paradigm for building and using these models is facing more and more privacy and legal *** bridge the gap between data privacy and the need for data fusion,an emerging AI paradigm feder-ated learning(FL)has emerged as an approach for solving data silos and data privacy *** on secure distributed AI,feder-ated learning emphasizes data security throughout the lifecycle,which includes the following steps:data preprocessing,training,evalu-ation,and *** keeps data security by using methods,such as secure multi-party computation(MPC),differential privacy,and hardware solutions,to build and use distributed multiple-party machine-learning systems and statistical models over different data *** data privacy concerns,we argue that the concept of“model”matters,when developing and deploying federated models,they are easy to expose to various kinds of risks including plagiarism,illegal copy,and *** address these issues,we introduce FedIPR,a novel ownership verification scheme,by embedding watermarks into FL models to verify the ownership of FL models and protect model intellectual property rights(IPR or IP-right for short).While security is at the core of FL,there are still many articles re-ferred to distributed machine learning with no security guarantee as“federated learning”,which are not satisfied with the FL definition supposed to *** this end,in this paper,we reiterate the concept of federated learning and propose secure federated learning(SFL),where the ultimate goal is to build trustworthy and safe AI with strong privacy-preserving and *** provide a com-prehensive overview of existing works,including threats,attacks,and defenses in each phase of SFL from the lifecycle perspective.

关键词： Federated learning privacy-preserving machine learning security decentralized learning intellectual property protection

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氨气掺混乙烯层流燃烧速度测量及动力学分析

工程热物理学报 2024年第2期45卷 558-568页

作者：刘博文郭晓阳胡二江殷阁媛黄佐华西安交通大学动力工程多相流国家重点实验室西安710049

本文利用定容燃烧弹测量了不同掺混比(0-1)下NH_(3)/C_(2)H_(4)/air火焰的层流燃烧速度。对NH3/air、C_(2)H_(4)/air层流燃烧速度进行验证,并利用Konnov Mech(2021)及GRI 3.0模型对NH_(3)/C_(2)H_(4)/air火焰层流燃烧速度进行数值计算和动力学分析,其中Konnov机理表现出不错的性能。结果表明,C2H4的添加提高了层流燃烧速度,同时,NH_(3)和C_(2)H_(4)掺混,拓展了反应路径,通过一系列组分NO、ch_(3)等来交互加快反应。最后,通过分析活性自由基H、O、OH的浓度,探究了不同机理在预测层流燃烧速度产生差异的原因。

关键词：氨气乙烯层流燃烧速度化学反应动力学

Tradeoff between heating energy demand in winter and indoor overheating risk in summer constrained by building standards

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Building Simulation 2021年第4期14卷 987-1003页

作者： Ran Wang Shilei Lu Wei Feng bowen Xu School of Environment Science and Engineering Tianjin University92 Weijin RoadTianjin300072China Tianjin Key Laboratory of Built Environment and Energy Application Tianjin UniversityTianjin300350China Lawrence Berkeley National Laboratory BerkeleyCA94720USA

Evidence indicates that improvement of thermal performance of building envelope has the potential for aggravating the indoor overheating risk in summer. On the other hand, evolving building standards continue to strengthen the requirements for thermal performance to achieve the energy-saving target. Therefore, this study quantifies the interaction effect between building standards-oriented building design, heating energy demand in winter, and indoor overheating risk in summer. Building databases with different energy efficiency levels are generated using a randomly generated method. Uncertain variables include not only 13 design parameters but also the running state of natural ventilation and external shading. The indoor overheating risk is assessed in terms of severity and duration. Finally, a multi-objective optimization model integrating metamodels and the non-dominated sorting genetic algorithm is proposed to balance heating energy demand in winter and indoor overheating risk in summer. Results indicate that building standards tend to aggravate overheating risk in summer: the duration and severity of high-performance buildings increased by 40.6% and 24.2% than that of conventional-performance buildings. However, window ventilation could offset the adverse effect, and mitigation of duration and severity can be up to 85.2% and 62.1% for high-performance buildings. Window ventilation can weaken the conflict between heating energy demand in winter and overheating risk in summer. As heating energy demand increased from 6.1 to 67.3 kWh/m^(2), the overheating risk ch.nges little that the duration of overheating risk decreased from 17.5% to 15.6% and severity decreased from 8.7 ℃ to 8.3 ℃.

关键词： climate ch.nge indoor overheating risk energy codes building design natural ventilation

Return just your search:privacy-preserving homoglyph search for arbitrary languages

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Frontiers of Computer Science 2022年第2期16卷 140-151页

作者： bowen ZHAO Shaohua TAng Ximeng LIU Yiming WU School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Zheng Zhiming Lab Peng Cheng LaboratoryShenzhen 518055China College of Mathematics and Computer Science Fuzhou UniversityFuzhou 350108China

Searchable encryption is an effective way to ensure the security and availability of encrypted outsourced cloud *** existing solutions,the keyword exact search solution is relatively inflexible,while the fuzzy keyword search solution either has a high index overhead or suffers from the ***,no existing fuzzy keyword search solution considers the homoglyph search on encrypted *** this paper,we propose an efficient privacy-preserving homoglyph search scheme supporting arbitrary languages(POSA,in short).We enhance the performance of the fuzzy keyword search in three ***,we formulate the similarity of homoglyph and propose a privacy-preserving homoglyph ***,we put forward an index build mechanism without the false-positive,which reduces the storage overhead of the index and is suitable for arbitrary ***,POSA returns just the user’s search,i.e.,all returned documents contain the search keyword or its *** theoretical analysis and experimental evaluations on real-world datasets demonstrate the effectiveness and efficiency of POSA.

关键词： searchable encryption cloud storage fuzzy search privacy preservation arbitrary languages

Development of anti-oxidation Ag salt paste for large-area(35×35 mm^(2))Cu-Cu bonding with ultra-high bonding strength

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Journal of Materials Science & Technology 2022年第18期113卷 261-270页

作者： bowen Zhang chuantong chen Takuya Sekiguchi Yang Liu Caifu Li Katsuaki Suganuma The Institute of Scientific and Industrial Research Osaka UniversityIbaraki-shiOsaka 567-0047Japan School of electrical and electronic engineering Tiangong UniversityTianjin 300387China Central Research Center Research and Development DivisionTOPPAN FORMS CO.LTD1-2-6 Owada-choHachioji-shiTokyoJapan School of materials and state key laboratory of optoelectronic materials and technologies Sun Yat-sen UniversityShenzhen 518107China

In this paper,by proposing a novel and low-cost Ag salt paste,a robustly and large-area(35×35 mm^(2))bare Cu to Cu bonding was realized under a low sintering pressure of 0.8 MPa and a low sintering temperature of 300℃ in air atmospheric *** relationship between the bonding strength and microstructure ch.nges of sintered Ag under various bonding conditions was investigated in *** large-area bonded plate exhibits low porosity about 10%and low percentage of voids,which result in ultra-high bonding strength over 58 *** importantly,the introduction of reducing agent formic acid(ch_(2)O_(2))and the low porosity successfully improve the anti-oxidation of novel Ag salt paste during sintering process,result in pure Cu-Ag-Cu *** cross-section of the Ag joints was obtained to explain the bonding pattern,in which Cu was oxidized only at the edge of the sintering interface,and no Cu oxide generated in middle bonding *** development of novel Ag salt paste successfully addresses the energy-intensive process and low bonding strength faced by large-scale sintering,which greatly promotes the high-temperature applications of power device.

关键词： Large-area bonding Anti-oxidation Cu-cu joint Ag salt paste Bonding strength