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噻吩酰亚胺衍生物二阶非线性光学性质的DFT研究

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原子与分子物理学报 2025年第1期42卷 20-28页

作者：蔺彬彬闫慧君哈尔滨学院食品工程学院化学系哈尔滨150086

采用密度泛函理论(DFT)CAM-B3LYP方法,计算研究了12个设计的噻吩酰亚胺衍生物的电子光谱和二阶非线性光学性质.结果表明,此类化合物有较大的第一超极化率β_(tot)值和β_(vec)值,且β_(tot)值和β_(vec)值随引入氰基数目的增加而显著增... 详细信息

采用密度泛函理论(DFT)CAM-B3LYP方法,计算研究了12个设计的噻吩酰亚胺衍生物的电子光谱和二阶非线性光学性质.结果表明,此类化合物有较大的第一超极化率β_(tot)值和β_(vec)值,且β_(tot)值和β_(vec)值随引入氰基数目的增加而显著增大.给/吸电子基团引起的电荷转移变化对体系β_(tot)值和β_(vec)值的影响大于分子六元杂环中N杂原子位置变化对其影响.

关键词：噻吩酰亚胺衍生物密度泛函理论二阶非线性光学性质电子光谱

Solar trough receiver with V-grooved light traps for efficiency improvement

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Science China Technological Sciences 2025年第1期 146-156页

作者： bin LIU Qing LI Yu QIU School of energy Science and engineering Central South University

Parabolic trough collector is a promising technology for both domestic and industrial heat supplies. To enhance the collector efficiency, a modified trough receiver with dozens of V-grooved light traps incorporated into its lower-half absorber was introduced. For assessing the performance of this receiver, a solar-thermal-stress coupled model was established. Using this model, firstly, the effects of the V-grooved light traps were investigated. The results reveal that, compared to the conventional trough receiver, the modified trough receivers equipped with different traps can reduce their optical losses by 81.9–138.0 Wm-1（i.e., 15.0%–25.2%）, improving their optical efficiencies by 1.60%–2.69%. However, these traps also result in increased thermal loss from the receiver. Therefore, there is no single optimal modified trough receiver that consistently outperforms all other receivers across all possible conditions. Nonetheless, the MTR30-3 and MTR60-3 receivers emerge as the optimized choices due to their better solar-thermal performance. Subsequently, performance evaluation reveals that the two optimized receivers can enhance the receiver efficiencies within the typical solar irradiance range by 0.02%–2.65% and 0.05%–1.70% when the inlet fluid temperatures are below 488 and 523 K, respectively. Consequently, the collector efficiencies can be improved by 0.02%–2.49% and 0.05%–1.60%, respectively. Additionally, thermal stress analysis verifies that the two optimized receivers remain within safe limits under all typical conditions. Given that the heating temperature of a typical solar collector for domestic or industrial heat supply is typically below 523 K, the integration of the two optimized receivers has the capability to effectively enhance the overall collector efficiency.

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Annealing effect of Pulsed Laser Deposited Transparent Conductive Ta-Doped Titanium Oxide Films

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Chinese Physics Letters 2011年第11期28卷 239-242页

作者： WU bin-bin PAN Feng-Ming YANG Yu-e Department of Applied Physics College of ScienceNanjing University of Aeronautics and AstronauticsNanjing 211100

Tantalum-doped TiO_(2) films were deposited on glass at 300℃ by pulsed laser deposition(PLD).After postannealing in vacuum(∼10^(−4) Pa)at temperatures ranging from 450℃ to 650℃,these films were crystallized into an anatase TiO_(2) structure and presented good conductive *** increasing annealing temperature up to 550℃,the resistivity of the films was measured to be around 8.7×10^(−4)Ω・*** films exhibit high transparency of over 80%in the visible light *** results indicate that tantalum-doped anatase TiO_(2) films have a great potential as transparent conducting oxides.

关键词： annealing Titanium transparency

Interactions between invasive eurasian watermilfoil and native water stargrass in Cayuga Lake, NY, USA

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Journal of Plant ecology 2014年第6期7卷 499-508页

作者： bin Zhu Samuel e.Georgian Department of Biology University of Hartford200 Bloomfield AvenueWest HartfordCT 06117USA Department of Biology Temple University1900 N 12 StreetPhiladelphiaPA 19122USA

Aims eurasian watermilfoil(Myriophyllum spicatum L.)is a common invasive plant in American lakes and has many negative impacts on invaded *** decline of this plant at the north-ern end of Cayuga Lake in the New York State has occurred since the 1980s,with a much smaller magnitude of decline of eurasian watermilfoil at the southern end(Johnson et al.2000)During the same period,increases in the abundance of native plants,partic-ularly water stargrass(Heteranthera dubia(Jacq.)MacMill.),have been observed(Johnson et al.(1998))We aimed to investigate the mechanisms responsible for the decline of eurasian watermilfoil and evaluate the responses of co-occurring plants at the two ends of Cayuga Lake over *** hypothesized that plant interactions might have contributed to the drastic decline of eurasian watermil-foil,particularly allelopathy by native water *** A lake survey was conducted to assess distribution and abundance of plant communities at the northern end and the southern end of Cayuga ***,two sets of greenhouse ex.eriments were conducted to investigate the interactions between invasive eurasian watermilfoil and native water stargrass.A competition ex.eriment evaluated intra-versus inter-specific competition among plants grown together;an allelopathy ex.eriment examined the responses of plants to each other’s *** Findings The lake survey showed that water stargrass was extremely abun-dant at the northern end,whereas eurasian watermilfoil was sparse at the northern end but one of the most common species at the southern *** survey also revealed that water stargrass was more abundant than eurasian watermilfoil at sites where the two species coexisted in the *** from greenhouse ex.eri-ments revealed no effects of eurasian watermilfoil on water star-grass ***,eurasian watermilfoil biomass was reduced by 46%when treated with high concentration of water stargrass *** is likely d

关键词： allelopathy biological invasion plant interactions space competition submerged macrophytes

efficient catalytic hydrogen generation by intermetallic platinum-lead nanostructures with highly tunable porous feature

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Science Bulletin 2019年第1期64卷 36-43页

作者： bin e Lingzheng Bu Qi Shao Yujing Li xiaoqing Huang College of Chemistry Chemical Engineering and Materials Science Soochow University Department of Materials Science and engineering China University of Petroleum College of Materials Beijing Institute of Technology

The water-gas shift(WGS) reaction is an essential industrial reaction for upgrading hydrogen(H2) by removing carbon monoxide(CO), while highly efficient platinum(Pt)-based catalysts for WGS with simultaneously high activity and stability are still yet to be developed due to the poisoning issue during the reaction. Herein, we report on the porous PtPb peanut nanocrystals(porous PtPb PNCs) and porous PtPb octahedron nanocrystals(porous PtPb ONCs) with controllable ratios of Pt/Pb as extremely active and stable catalysts towards WGS reaction. It exhibits the composition-dependent activity with porous PtPb PNCs-40/ZnO being the most active for WGS to H_2, 16.9 times higher than that of the commercial Pt/C. The porous PtPb PNCs-40/ZnO also display outstanding durability with barely activity decay and negligible structure and composition changes after ten successive reaction cycles. x-ray photoelectron spectroscopy(xPS) results reveal that the suitable binding energy of Pt 4f_(7/2) and the high ratio of Pt(0)to Pt(II) in porous PtPb PNCs/ZnO and porous PtPb ONCs/ZnO are crucial for the enhanced WGS *** CO stripping results indicate the optimized CO adsorption strength on the Pt surface ensure the ex.ellent WGS activity and the outstanding durability. The present work demonstrates an important advance in tuning the porous metal nanomaterials as highly efficient and durable catalysts for catalysis,energy conversion and beyond.

关键词： Porous Selective etching Hydrogen Pt-Pb Water-gas shift

Cavitation research with computational fluid dynamics:From euler-euler to euler-Lagrange approach

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Journal of Hydrodynamics 2024年第1期36卷 1-23页

作者： bin Ji Zi-yang Wang Huai-yu Cheng Rickard e.Bensow State Key Laboratory of Water Resources engineering and Management Wuhan UniversityWuhan430072China Department of Mechanics and Maritime Sciences Chalmers University of TechnologyGothenburgSweden

Unsteady cavitating flow often contains vapor structures with a wide range of different length scales,from micro-bubbles to large cavities,which issues a big challenge to precisely investigate its evolution mechanism by computational fluid dynamics(CFD)*** present work reviews the development of simulation methods for cavitation,especially the emerging euler-Lagrange ***,the progress of the numerical investigation of hot and vital issues is discussed,including cavitation inception,cloud cavitation inner structure and its formation mechanism,cavitation erosion,and cavitation *** is indicated that the euler-Lagrange method can determine cavitation inception point *** cloud cavitation,the euler-Lagrange method can reveal the source of microbubbles and their distribution law inside the shedding *** method also has advantages and great potential in assessing cloud cavitation-induced erosion and *** the ever-growing demands of cavitation simulation accuracy in basic research and engineering applications,how to improve the euler-Lagrange method’s stability and applicability is still an open *** further promote the application of this advanced CFD simulation technology in cavitation research,some key issues are to be solved and feasible suggestions are put forward for further work.

关键词： numerical simulation euler-euler method euler-Lagrange method bubble dynamicsgy,Gothenburg,Sweden

Two New Pentacyclic Triterpenes from Sabia parviflora

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Chinese Chemical Letters 2002年第4期13卷 345-348页

作者： Jin CHeN bin CHeN Jun TIAN Feng e WU Laboratory of Natural Materia Medica Chengdu Institute of BiologyAcademia SinicaChengdu 610041

Two new pentacyclic triterpene acids, 1a, 3b-dihydroxyl-olean-12-en-28-oic acid and 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora.

关键词： Sabia parviflora pentacyclic triterpene acid 1α, 3b-dihydroxyl-olean-12-en-28-oic acid 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid.

A New Benzylisoquinoline Alkaloid from Sabia parviflora

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Chinese Chemical Letters 2002年第5期13卷 426-427页

作者： Jin CHeN bin CHeN Jun TIAN Feng e WU Laboratory of Natural Materia Medica Chengdu Institute of BiologyAcademia SinicaChengdu 610041

A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the bas... 详细信息

关键词： Sabia parviflora benzylisoquinoline alkaloid 1, 2, 3, 4-tetrahydro-5-hydroxyl-8- methoxyl-2-methyl-4'-methoxyl-benzylisoquinoline.

Particle Simulation of the Fast Ignition Mechanism for Laser Fusion

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Chinese Physics Letters 2001年第6期18卷 799-801页

作者： ZHANG Jia-Tai He bin N.e.Andreev Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088 Joint Institute for High Temperature Russian Academy of SciencesMoscow 127412Russia

We have developed the two and half-dimension electromagnetic relativistic electron and mobile ion cloud-in-cell(CIC)*** of the fast ignition and interaction of ultra-intense and ultra-short pulse laser with plasma are analysed theoretically and simulated numerically using CIC *** flows of relativistic electron and form of the channel are *** results show that the temperature of superhot electron is about MeV to tens of MeV,and the boring velocity is 0.05c-0.1c with c being the light *** preliminary scale laws are *** simulation quantitatively reproduces the ex.erimental results at early and long times.

关键词： relativistic intense dimension