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Emission of greenhouse gases from sewer networks:field assessment and isotopic characterization

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Frontiers of Environmental Science & Engineering 2024年第10期18卷 1-13页

作者： xin yuan Xianguo Zhang Yuqi Yang Xuan Li xin xing Jiane Zuo State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Capital Eco-Pro Group Beijing 100444China Tsinghua Shenzhen International Graduate School Shenzhen 518055China

Sewer networks play a vital role in sewage collection and transportation,and they are being rapidly ***,the microbial processes occurring within these networks have emerged as significant contributors to greenhouse gas(GHG)*** to that from other sectors,our understanding of the magnitude of GHG emissions from sewer networks is currently *** this study,we conducted a GHG emission assessment in an independent sewer network located in Beijing,*** findings revealed annual emissions of 62.3 kg CH_(4) and 0.753 kg ***_(4) emerged as the primary GHG emitted from sewers,accounting for 87.4%of the total GHG ***,compared with main pipes,branch pipes were responsible for a larger share of GHG emissions,contributing to 76.7%of the total.A GHG emission factor of 0.26 kg CO_(2)-eq/(m:yr)was established to quantify sewer GHG *** examining the isotopic signatures of CO_(2)/CH_(4) pairs,it was determined that CH_(4) production in sewers primarily occurred through acetate ***,the structure of sewer pipes had a significant impact on GHG *** study offers valuable insights into the overall GHG emissions associated with sewer networks and sheds ight on themechanismsdriving theseemissions.

关键词： Sewer network Greenhousegases Stablecarbon isotopes Methane Nitrous oxide

Effect of inlet rotating swirl on endwall film cooling for two representative hole arrangements

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Chinese Journal of Aeronautics 2018年第5期31卷 1095-1108页

作者： Yang ZHOU Yang ZHANG xinrong SU xin yuan Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Tsinghua University

The swirl generator is widely used in lean-burn combustor to guarantee flame stability and reduce NOxemissions. Thus, the non-uniformities induced by the swirler would affect and damage film-cooling effectiveness on the turbine components, even blow-off coolant coverage, to some certain extent. The arrangement of film-cooling holes was normally designed to be perpendicular to the axial direction and in standard straight row. In this work we experimentally studied the effects of inlet swirl and mass flow ratio on traditional film cooling holes arrangement and a new arrangement pattern whose holes are located along the isobars. Results indicated that the swirl perturbation would damage film coverage. The film-cooling effect of endwall on which the holes are along the isobars, is invariably more promising than that of endwall on which hole arrangement is perpendicular to axial with the same mass flow of coolant, whether the inlet conditions is uniform or not.

关键词： Films-cooling Holes locating Isobaric Swirling flow Turbine design

Catalytic hydrolysis of gaseous HCN over Cu-Ni/γ-Al2O3 catalyst： parameters and conditions

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Frontiers of Environmental Science & Engineering 2016年第6期10卷 141-148页

作者： Linxia Yan Senlin Tian Jian Zhou xin yuan Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming 650500 China

To decompose efficiently hydrogen cyanide （HCN） in exhaust gas, γ-Al2O3-supported bimetallicbased Cu-Ni catalyst was prepared by incipient-wetness impregnation method. The effects of the calcination temperature, H2O/HCN volume ratio, reaction temperature, and the presence of CO or O2on the HCN removal efficiency on the Cu-Ni/γ-Al2O3 catalyst were investigated. To examine further the efficiency of HCN hydrolysis, degradation products were analyzed. The results indicate that the HCN removal efficiency increases and then decreases with increasing calcination temperature and H2O/HCN volume ratio. On catalyst calcined at 400℃, the efficiency reaches a maximum close to 99% at 480 min at a H2O/HCN volume ratio of 150. The HCN removal efficiency increases with increasing reaction temperature within the range of 100v-500℃ and reaches a maximum at 500℃.This trend may be attributed to the endothern＇ficity of HCN hydrolysis; increasing the temperature favors HCN hydrolysis. However, the removal efficiencies increases very few at 500℃ compared with that at 400℃. To conserve energy in industrial operations, 400℃ is deemed as the optimal reaction temperature. The presence of CO facilitates HCN hydrolysis andincreases NH3 production. 02 *** increases the HCN removal efficiency and NOx production but decreases NH3 production.

关键词： Hydrogen cyanide Cu-Ni/γ-Al2O3 Catalytic hydrolysis

Single-pixel neutron imaging with artificial intelligence: Breaking the barrier in multi-parameter imaging, sensitivity, and spatial resolution

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The Innovation 2021年第2期2卷 172-173页

作者： xin yuan Shensheng Han Bell Labs Murray HillNJ 07974USA Key Laboratory for Quantum Optics of CAS Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Different from X-rays,neutrons mainly interact with atomic nuclei and magnetic moments in *** makes neutron imaging a complementary contrast mechanism to X-ray *** imaging aims to infer the internal material information of the object by measuring the changes in neutron beam parameters,such as the intensity attenuation,polarization,scattering,and matter wave *** has a wide range of applications in industry such as the inspection of batteries,magnetic structure analysis,and strain mapping in alloys.

关键词： materials. complementary parameter

Wing walls for enhancing the seismic performance of reinforced concrete frame structures

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 411-423页

作者： Yang Weisong Guo Xun Xu Weixiao yuan xin School of Civil Engineering Qingdao University of Technology Qingdao 266033 China Collaborative Innovation Center of Engineering Construction and Safety in Shandong Blue Economic Zone Qingdao 266033 China Institute of Disaster Prevention Sanhe 06520 China Sichuan Provincial Architectural Design and Research Institute Chengdu 610000 China

A building retrofitted with wing walls in the bottom story, which was damaged during the 2008 M8.0 Wenchuan earthquake in China, is introduced and a corresponding 1/4 scale wing wall-frame model was subjected to shake table motions to study the seismic behavior of this retrofitted structural system. The results show that wing walls can effectively protect columns from damage by moving areas that bear reciprocating tension and compression to the sections of the wing walls, thus achieving an extra measure of seismic fortification. A ‘strong column-weak beam＇ mechanism was realized, the flexural rigidity of the vertical member was strengthened, and a more uniform distribution of deformation among all the stories was measured. In addition, the joint between the wing walls and the beams suffered severe damage during the tests, due to an area of local stress concentration. A longer area of intensive stirrup is suggested in the end of the beams.

关键词： story walls flexural shake columns suffered sections drift reinforced frames

Telluride semiconductor nanocrystals:progress on their liquid-phase synthesis and applications

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Rare Metals 2022年第8期41卷 2527-2551页

作者： Meng-Yao Su xin-yuan Li Jia-Tao Zhang Institute of Engineering Medicine Beijing Institute of TechnologyBeijing100081China MOE Key Laboratory of Cluster Science School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing100081China

The synthesis of colloidal telluride semiconductor nanocrystals(CT-SNCs)is more challenging than that of chalcogenides,due to the smaller electron affinity of tellurium than that of sulfur and selenium,which is attributed to its metalloid *** some new potential strategies were developing with the increasing demand of CT-SNCs,the cation exchange reaction(CER)has particularly become a new strategy to synthesize highquality CT-SNCs and their corresponded *** review summarizes the synthesis strategies of CT-SNCs,including traditional methods and new methods with emphasis on CERs,and their resulting CTSNCs with well-controlling size,shape,composition,crystallization and hetero-interfaces *** progressive synthesis methods give rise to the excellent optical properties of *** review also covers the recent progress of their applications in the field of photoelectric detection,catalysis,batteries and *** new hybrid CT-SNCs nanostructures are also emphasized and systematically discussed due to their enhanced properties.

关键词： Telluride semiconductor nanocrystals Cation exchange reaction Quantum dots Optoelectronic application

Enantioselective esterification of(R,S)-2-(4-methylphenyl)propionic acid via Novozym 435:Optimization and application

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Chinese Journal of Chemical Engineering 2020年第7期28卷 1816-1823页

作者： xin yuan LujunWang Panliang Zhang Weifeng Xu Kewen Tang Department of Chemistry and Chemical Engineering Hunan Institute of Science and TechnologyYueyang 414006China

This paper reports on the resolution of(R,S)-2-(4-methylphenyl)propionic acid(MPPA)enantiomers by enzymatic esterification in organic *** 435(CALB)has the best catalytic performance compared with other *** the alcohols screened,n-hexanol is the best acyl acceptor and gives the highest enzyme activity and enantioselectivity in *** surface methodology(RSM)was used to evaluate the influence of the factors,such as temperature,enzyme amount,substrate concentration and reaction time on the substrate conversion(c)and enantiomeric excess(ee).The correlation coefficient R2 for enantiomeric excess and the conversion are 0.9827 and 0.9910,respectively,indicating that can accurately predict the experimental *** simulation and optimization,the optimal conditions were obtained,involving 600 mmol·L^-1 MPPA concentration(0.60 mmol),850 mmol·L^-1 hexanol concentration(0.85 mmol),58 mg enzyme amount,75℃temperature and 4.5 h reaction time,*** the optimized conditions,the experimental values of conversion and enantiomeric excess were 89.34%and 97.84%,respectively,which are in good agreement with the model predictions.

关键词： (R,S)-2-(4-Methylphenyl)propionic acid Novozym 435 Esterification kinetic resolution Response surface methodology

Extraction of Tungsten and Molybdenum by Various Organic Compounds as Extractants

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Rare Metals 1989年第3期9卷 15-19页

作者： yuan, Qun Cheng, xin Luo, Jiazhen yuan, Chengye Shanghai Inst of Organic Chemistry China

Seventy organic compounds including various organophosphorus esters, amines and oxygen-based ligands were investigated as extractants. The experiment results show that amines are excellent extractants for W and Mo. Their sequence of extraction ability for W is as follows: quarternary amine > tertiary amine > secondary amine > primary amine. Acidic organophosphorus extractants do not extract W, but can extract Mo with high extraction ability from the acidic solution. These extractants could provide a potential process for separating W from Mo.

关键词： Alcohols Applications Amines Applications Molybdenum Ore Treatment Solvent Extraction Phosphorus Compounds Organic Solvents Organic

Plant Ionomics： From Elemental Profiling to Environmental Adaptation

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Molecular Plant 2016年第6期9卷 787-797页

作者： xin-yuan Huang David E. Salt Institute of Biological and Environmental Sciences University of Aberdeen Cruickshank Building St Machar Drive Aberdeen AB24 3UU UK

Ionomics is a high-throughput elemental profiling approach to study the molecular mechanistic basis underlying mineral nutrient and trace element composition （also known as the ionome） of living organisms. Since the concept of ionomics was first introduced more than 10 years ago, significant progress has been made in the identification of genes and gene networks that control the ionome. In this update, we summa- rize the progress made in using the ionomics approach over the last decade, including the identification of genes by forward genetics and the study of natural ionomic variation. We further discuss the potential application of ionomics to the investigation of the ecological functions of ionomic alleles in adaptation to the environment.

关键词： nutrient homeostasis natural variation ionomics Arabidopsis thaliana Casparian strip adaptation