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Effect of different doping elements on performance of Ce-Mn/TiO_(2)catalyst for low temperature denitration

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Journal of Rare Earths 2023年第5期41卷 689-697,I0002页

作者： Lihua Huang jian Hua Insititute of Environment and Resources Southwest University of Science and TechnologyMianyang 621010China National Engineering Research Center for Flue Gas Desulfurization Chengdu 610065China

Sm and Ho were doped in Ce-Mn/TiO_(2)catalyst respectively to enhance its denitration performance at low temperature.X-ray diffraction(XRD),N2adsorption-desorption,X-ray photoelectron spectroscopy(XPS),NH3-temperature programmed desorption(NH3-TPD),H2-temperature programmed reduction(H2-TPR)and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)techniques were used to analyze the structure and performance of *** results demonstrate that Ho doping increases the amount of acid sites and improves low temperature redox property of Ce-Mn/TiO_(2),which lead to excellent DeNOxperformance of Ho-Ce-Mn/TiO_(2)in the whole reaction temperature *** doping results in decline of redox property,but it is beneficial to increasing the acid sites of Ce-Mn/TiO_(2).The increased surface acid sites and moderate oxidative ability impart Sm-Ce-Mn/TiO_(2)higher denitration activity and N2selectivity at temperature above 150℃.Lewis acid sites and redox property are the main factors affecting the activity of *** of Ho and Sm both improves sulfur resistance performance of Ce-Mn/TiO_(2)by inhibiting the adsorption of SO_(2)and formation of ***-Mn/TiO_(2)modified by Ho shows better sulfur resistance than that doped with Sm because of its more surface acid sites.

关键词： Ce-Mn/TiO_(2)catalyst Doping Sm Ho Denitration performance Rareearths

Thermal comfort in winter incorporating solar radiation effects at high altitudes and performance of improved passive solar design-Case of Lhasa

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Building Simulation 2021年第6期14卷 1633-1650页

作者： Lingjiang Huang jian Kang Department of Architecture Wuhan UniversityWuhan 430072China UCL Institute for Environmental Design and Engineering The BartlettUniversity College London(UCL)London WC1H 0NNUK

The solar incidence on an indoor environment and its occupants has significant impacts on indoor thermal *** can bring favorable passive solar heating and can result in undesired overheating(even in winter).This problem becomes more critical for high altitudes with high intensity of solar irradiance,while received limited *** this study,we explored the specific overheating and rising thermal discomfort in winter in Lhasa as a typical location of a cold climate at high ***,we evaluated the thermal comfort incorporating solar radiation effect in winter by field ***,we investigated local occupant adaptive responses(considering the impact of direct solar irradiance).This was followed by a simulation study of assessment of annual based thermal comfort and the effect on energy-saving potential by current solar ***,we discussed winter shading design for high altitudes for both solar shading and passive solar use at high altitudes,and evaluated thermal mass shading with solar louvers in terms of indoor environment *** results reveal that considerable indoor overheating occurs during the whole winter season instead of summer in Lhasa,with over two-thirds of daytime beyond the comfort ***,various adaptive behaviors are adopted by occupants in response to overheating due to the solar ***,it is found that the energy-saving potential might be overestimated by 1.9 times with current window to wall ratio requirements in local design standards and building codes due to the thermal adaption by drawing *** developed thermal mass shading is efficient in achieving an improved indoor thermal environment by reducing overheating time to an average of 62.2% during the winter and a corresponding increase of comfort time.

关键词： thermal comfort overheating passive solar design high altitude Tibet solar shading

Development in oxide metallurgy for improving the weldability of high -strength low-alloy steel-Combined deoxidizers and microalloying elements

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1263-1284页

作者： Tingting Li jian Yang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The mechanisms of oxide metallurgy include inducing the formation of intragranular acicular ferrite(IAF)using micron-sized inclusions and restricting the growth of prior austenite grains(PAGs)by nanosized particles during *** chaotically oriented IAF and refined PAGs inhibit crack initiation and propagation in the steel,resulting in high impact *** work summarizes the com-bined effect of deoxidizers and alloying elements,with the aim to provide a new perspective for the research and practice related to im-proving the impact toughness of the heat affected zone(HAZ)during the high heat input *** complex deoxidation with other strong deoxidants,such as Mg,Ca,Zr,and rare earth metals(REMs),can improve the toughness of the heat-affected zone(HAZ)by re-fining PAGs or increasing IAF ***,it is difficult to identify the specific phase responsible for IAF nucleation because ef-fective inclusions formed by complex deoxidation are usually *** alloying elements,such as C,Si,Al,Nb,or Cr,con-tents can impair HAZ toughness.A high C content typically increases the number of coarse carbides and decreases the potency of IAF ***,Cr,or Al addition leads to the formation of undesirable *** reduces the high-temperature stability of the ***,V,and B can enhance HAZ ***-containing precipitates present good thermal *** or V(C,N)is ef-fective in promoting IAF nucleation due to its good coherent crystallographic relationship with *** formation of the B-depleted zone around the inclusion promotes IAF *** interactions between alloying elements are complex,and the effect of adding dif-ferent alloying elements remains to be *** the future,the interactions between various alloying elements and their effects on ox-ide metallurgy,as well as the calculation of the nucleation effects of effective inclusions using first principles calculations will become the focus of

关键词： oxide metallurgy technology heat affected zone high-strength low-alloy steel intragranular acicular ferrite microalloying element

Physics and applications of Raman distributed optical fiber sensing

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Light(Science & Applications) 2022年第6期11卷 1059-1087页

作者： jian Li Mingjiang Zhang College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuanShanxi 030024China Key Laboratory of Advanced Transducers and Intelligent Control Systems(Ministry of Education and Shanxi Province) Taiyuan University of TechnologyTaiyuan 030024China

Raman distributed optical fiber sensing has been demonstrated to be a mature and versatile scheme that presents great flexibility and effectivity for the distributed temperature measurement of a wide range of engineering applications over other established *** past decades have witnessed its rapid development and extensive applicability ranging from scientific researches to industrial ***,there are four theoretical or technical bottlenecks in traditional Raman distributed optical fiber sensing:(ⅰ)The difference in the Raman optical attenuation,a low signal-to-noise ratio(SNR)of the system and the fixed error of the Raman demodulation equation restrict the temperature measurement accuracy of the system.{ⅱ)The sensing distance and spatial resolution cannot be reconciled.(ⅲ)There is a contradiction between the SNR and measurement time of the system.(ⅳ)Raman distributed optical fiber sensing cannot perform dual-parameter *** on the above theoretical and technical bottlenecks,advances in performance enhancements and typical applications of Raman distributed optical fiber sensing are reviewed in this *** of this optical system technology with knowledge based,that is,demodulation technology *** further the performance and accuracy of these systems.

关键词： fiber optical contradiction

Electromagnetohydrodynamic flows and mass transport in curved rectangular microchannels

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Applied Mathematics and Mechanics(English Edition) 2020年第9期41卷 1431-1446页

作者： Yongbo LIU Yongjun jian School of Mathematical Science Inner Mongolia UniversityHohhot 010021China

Curved microchannels are often encountered in lab-on-chip systems because the effective axial channel lengths of such channels are often larger than those of straight microchannels for a given per unit chip *** this paper,the effective diffusivity of a neutral solute in an oscillating electromagnetohydrodynamic(EMHD)flow through a curved rectangular microchannel is investigated *** flow is assumed as a creeping flow due to the extremely low Reynolds number in such microflow *** the theoretical analysis,we find that the effective diffusivity primarily depends on five dimensionless parameters,i.e.,the curvature ratio of the curved channel,the Schmidt number,the tidal displacement,the angular Reynolds number,and the dimensionless electric field strength *** on the obtained results,we can precisely control the mass transfer characteristics of the EMHD flow in a curved rectangular microchannel by appropriately altering the corresponding parameter values.

关键词： electromagnetohydrodynamic(EMHD)flow curved rectangular microchannel mass transfer characteristic effective diffusivity

Role of oxygen vacancy inducer for graphene in graphene-containing anodes

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Frontiers of Chemical Science and Engineering 2023年第3期17卷 326-333页

作者： Fei Wang jian Mao College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Currently,graphene is only considered as a conductive additive and expansion inhibitor in oxides/graphene composite *** this study,a new graphene role(oxygen vacancy inducer)in graphene/oxides composites anodes,which are treated at high-temperature,is proposed and verified using experiments and density functional theory *** high-temperature processing,graphene forms carbon vacancies due to increased thermal vibration,and the carbon vacancies capture oxygen atoms,facilitating the formation of oxygen vacancies in ***,the induced oxygen vacancy concentrations can be regulated by sintering temperatures,and the behavior is unaffected by oxide crystal structures(crystalline and amorphous)and morphology(size and shape).According to density functional theory calculations and electrochemical measurements,the oxygen vacancies enhance the lithiumion storage *** findings can result in a better understanding of graphene’s roles in graphene/oxide composite anodes,and provide a new method for designing high-performance oxide anodes.

关键词： oxide oxygen vacancy graphene anode density functional theory calculation

Development of acoustic computer simulation for performance spaces: A systematic review and meta-analysis

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Building Simulation 2022年第10期15卷 1729-1745页

作者： Chao Wang jian Kang School of Architecture Tianjin UniversityTianjin 300072China UCL Institute for Environmental Design and Engineering The BartlettUniversity College London(UCL)Central House14 Upper Woburn PlaceLondon WC1H0NNUK

This article aims to review the development of acoustic computer simulation for performance spaces. The databases of Web of Science and Scopus were searched for peer-reviewed journal articles published in English between 1960 and 2021, using the keywords for “simulation”, “acoustic”, “performance space”, “measure”, and their synonyms. The inclusion criteria were as follows: (1) the searched article should be focused on the field of room acoustics (reviews were excluded);(2) a computer simulation algorithm should be used;(3) it should be clearly stated that the simulated object is a performance space;and (4) acoustic measurements should be used for comparison with the simulation. Finally, twenty studies were included. A standardised data extraction form was used to collect the modelling information, software/algorithm, indicators for comparison, and other information. The results revealed that the most used acoustic indicators were early decay time (EDT), reverberation time (T30), strength (G), and definition (D50). The accuracy of these indicators differed greatly. For non-iterative simulation, the simulation accuracies of most indicators were outside their respective just noticeable differences. Although a larger sample size was required for further validation, simulations of T30, EDT, and D50 all showed an increase in accuracy with increasing time from 1979 to 2020, except for G. In terms of frequency, the simulation was generally less accurate at lower frequencies, which occurred at T30, G, D50 and T20. However, EDT accuracy did not exhibit significant frequency sensitivity. The prediction accuracy of inter-aural cross-correlation coefficients (IACC) was even higher at low frequencies than it was at high frequencies. The average value of most indicators showed a clear systematic deviation from zero, providing hints for future algorithm improvements. Limitations and the risks of bias in this review were discussed. Finally, various types of benchmark tests were sug

关键词： acoustic simulation accuracy systematic review performance space iterative simulation

Compositional dependence of thermophysical properties in binary alkaline earth borate melts:Insights from structure in short-range and intermediate-range order

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Journal of Materials Science & Technology 2022年第36期131卷 195-203页

作者： jian Yang Il Sohn Department of Materials Science and Engineering Yonsei UniversitySeoul120749Korea State Key Laboratory of Cemented Carbide Zhuzhou 412000China

In this work,the thermal conductivity of alkaline earth borate melts was measured using hot-wire method from 1323 to 1623 K,and the thermal diffusivity was extrapolated from the thermal conductivity and heat *** compositional dependence of thermophysical properties was interpreted according to the structure in short-range and intermediate-range *** on the Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and 11B magic-angle spinning nuclear magnetic resonance(MAS-NMR)spectra,modifier cation with higher field strength prefers the formation of non-bridging oxygens(NBOs)for the charge compensation at high BO_(1.5)/MO ratios.A lower amount of covalent bond and greater isolation of large borate groups lead to a lower thermal conductivity in calcium borate melt compared with strontium and barium *** the large size of Ba^(2+)encounters difficulty in fitting around B^[4]-OB^[4]linkages inside the overcrowded large borate groups when BO_(1.5)/BaO=2.5,promoting the formation of NBOs on the edge of borate groups for the charge compensation of modifier cations and leading to the decline in the thermal *** conductivity plays a major role in regulating the thermal diffusivity at a given temperature since the compositional dependence of volumetric heat capacity is relatively weak compared with that of thermal conductivity.

关键词： Thermal conductivity Magic-angle spinning nuclear magnetic resonance(MAS-NMR) X-ray photoelectron spectroscopy(XPS) Raman spectroscopy Thermal diffusivity

Advances in communications using optical vortices

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Photonics Research 2016年第5期4卷 14-28页

作者： jian Wang Wuhan National Laboratory for Optoelectronics School of Optical and Electronic Information Huazhong University of Science and Technology

An optical vortex having an isolated point singularity is associated with the spatial structure of light waves.A polarization vortex(vector beam) with a polarization singularity has spatially variant polarizations. A phase vortex with phase singularity or screw dislocation has a spiral phase front. The optical vortex has recently gained increasing interest in optical trapping, optical tweezers, laser machining, microscopy, quantum information processing, and optical communications. In this paper, we review recent advances in optical communications using optical vortices. First, basic concepts of polarization/phase vortex modulation and multiplexing in communications and key techniques of polarization/phase vortex generation and(de)multiplexing are introduced. Second, free-space and fiber optical communications using optical vortex modulation and optical vortex multiplexing are presented. Finally, key challenges and perspectives of optical communications using optical vortices are discussed. It is expected that optical vortices exploiting the space physical dimension of light waves might find more interesting applications in optical communications and interconnects.

关键词： OAM mode Advances in communications using optical vortices