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Exploring the effect of aggregation-induced emission on the excited state intramolecular proton transfer for a bis-imine derivative by quantum mechanics and our own n-layered integrated molecular orbital and molecular mechanics calculations

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Chinese Physics B 2019年第1期28卷 645-649页

作者：赵慧芳孙朝范刘晓春尹航石英 Institute of Atomic and Molecular Physics Jilin University

We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonomethyl)-naphthalene-2-ol and 1-pyrenecarboxaldehyde. Especially, the density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods for HNP monomer are introduced. Moreover, the "our own n-layered integrated molecular orbital and molecular mechanics"(ONIOM) method(TDDFT:universal force field(UFF)) is used to reveal the aggregation-induced emission(AIE) effect on the ESIPT process for HNP in crystal. our results confirm that the ESIPT process happens upon the photoexcitation for the HNP monomer and HNP in crystal, which is distinctly monitored by the optimized geometric structures and the potential energy curves. In addition, the results of potential energy curves reveal that the ESIPT process in HNP will be promoted by the AIE effect. Furthermore, the highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) for the HNP monomer and HNP in crystal have been calculated. The calculation demonstrates that the electron density decrease of proton donor caused by excitation promotes the ESIPT process. In addition, we find that the variation of atomic dipole moment corrected Hirshfeld population(ADCH) charge for proton acceptor induced by the AIE effect facilitates the ESIPT process. The results will be expected to deepen the understanding of ESIPT dynamics for luminophore under the AIE effect and provide insight into future design of high-efficient AIE compounds.

关键词： time-dependent density functional theory(TDDFT) method excited state intramolecular proton transfer(ESIPT) our own n-layered integrated molecular orbital and molecular mechanics(ONIOM) method potential energy curves atomic dipole moment corrected Hirshfeld population(ADCH) charge

Effect of Salinity Variations on the Performance of Activated Sludge System

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Biomedical and Environmental Sciences 2005年第1期18卷 5-8页

作者： JIAN-LONGWANG XIN-MINZHAN YE-CHENGFENG YIQIAN LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeijing100084China StateKeyJointLaboratoryofEnvironmentSimulationandPollutionControl TsinghuaUniversityBeijing100084China

To investigate the influence of salinity variations on the performance of activated sludge systems, treating domestic wastewater. Methods The completely mixed reactor was used and operated in a batch-wise mode. The activated sludge taken from the Gaobeidian Wastewater Treatment Plant was used as a seeding sludge. Total organic carbon (TOC), oxygen uptake rate (our) and suspended solids (SS) were used as parameters to characterize the performance of the treatment systems. TOC was measured using a TOC-analyzer (TOC-5000, Japan). The our value was measured with a dissolved oxygen meter (YSI model-58). SS was measured gravimetrically. Results The TOC removal efficiency and the our value of activated sludge were not deteriorated when the NaCl shock concentration was less than 0.5 g/L. However, when the NaCl shock concentrations were up to 10g/L and 20 g/L, the our of activated sludge was reduced by 35% and TOC removal efficiency was dropped by 30%, compared with the control experiment without NaCl shock loading. Conclusion The effect of NaCl shock loading on the activated sludge wastewater treatment system is dependant upon the NaCl concentrations and the degree of influence can be inferred through the change of substrate utilization rate at different shock NaCl loadings.

关键词： Activated sludge Saline wastewater NaCl Shock loading TOC our

Bis‐Lactam Peptide [i, i + 4]‐Stapling

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Chinese Journal of Chemistry 2019年第3期37卷 244-248页

作者： Xiao Hu Bo Wu Weiping Zheng School of Pharmacy Jiangsu University301 Xuefu RoadZhenjiangJiangsu 212013China

Summary of main observation and conclusion Even though the bis‐lactam peptide stapling with the [i, i + 7] and the [i, i + 11] systems has been known to be able to afford %α‐helicity values up to 100%(25°C), the performance of the bis‐lactam peptide stapling with the [i, i + 4] system in current literature has been mediocre (%α‐helicity ≦40%, 25℃). In the current study, we found that high %α‐helicity is also obtainable with the bis‐lactam [i, i + 4]‐stapling by demonstrating with our model peptide sequence that the bis‐lactam [i, i + 4]‐stapling with Nε‐para‐phenylenediacetyl‐lysine was able to afford a %α‐helicity value of ~64.1%(25℃). Therefore, the bis‐lactam [i, i + 4]‐stapling could also be an efficacious peptide stapling mode that can be employed for biomedical applications.

关键词： Bis bis has be our was can

Collective Synthesis of Schilancidilactones A, B and Schilancitrilactones A, B, C, 20‐epi‐Schilancitrilactone A

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Chinese Journal of Chemistry 2019年第3期37卷 255-268页

作者： Hengtao Wang Liang Wang Yihang Li Xiunan Zhang Pingping Tang State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300071China

Summary of main observation and conclusion Schisandraceae triterpenoids are novel natural products that contain highly fused ring systems bearing multiple chiral centers surrounding. Some of them exhibit promising bioactivities, such as antitumor, anti‐HIV, etc. In this article, we describe our efforts to the collective total synthesis of schilancidilactones A, B, schilancitrilactones A, B, C, and 20‐epi‐schilancitrilactone A from common precursors. An intramolecular radical cyclization, late‐stage halogenation and AIBN‐mediated or Ni‐catalyzed intermolecular radical cross coupling reaction were employed as the key steps.

关键词： epi multiple stage ring AIBN HIV our

Invasion of the biosphere by synthetic polymers:What our current knowledge may mean for our future

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Acta Oceanologica Sinica 2019年第5期38卷 161-164页

作者： Charles J.Moore Algalita Marine Research and Education

In 1974,a member of the Council of the British Plastics Federation and a fellow of the Plastics Institute,stated that“Plastics litter is a very small proportion of all litter and causes no harm to the environment except as an eyesore”(Derraik,2002).It has taken less than fifty years for that opinion to be completely discredited,indeed,that opinion was already in doubt the moment it was stated.Nevertheless,it was the strong denial by the plastic industry that plastics could cause harm that delayed the study of plastic’s environmental effects for decades.Not until Moore et al.(2001)found six times as much plastic as zooplankton by weight in the surface waters of the North Pacific Subtropical Gyre(NPSG).

关键词： Invasion the biosphere our future

低强度超声波强化污水生物处理中超声辐照污泥比例的优化选择

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环境科学 2006年第5期27卷 903-908页

作者：闫怡新刘红北京师范大学环境学院北京100875 北京航空航天大学环境工程系北京100083

通过超声波的SBR反应器与对照反应器处理人工配制生活污水的对比试验,研究了利用低强度超声波强化污水生物处理的另一个重要工艺参数———超声处理污泥比例(即超声处理污泥量占反应器内总污泥量的百分比).设置超声波反应器采用频率35kH... 详细信息

通过超声波的SBR反应器与对照反应器处理人工配制生活污水的对比试验,研究了利用低强度超声波强化污水生物处理的另一个重要工艺参数———超声处理污泥比例(即超声处理污泥量占反应器内总污泥量的百分比).设置超声波反应器采用频率35kHz、声强0.3W/cm2超声波每隔8h取反应器中一定比例的活性污泥辐照10min后再返回反应器.结果表明,超声处理污泥比例为10%时,其COD和NH3-N去除率可分别提高5%和0.5%左右,以好氧呼吸速率(Oxygen Uptake Rate,our)表示的污泥活性可提高12%以上.通过对污泥增长率的研究表明,当超声污泥比例为10%,超声波反应器内污泥的增长率比对照反应器降低了11%左右,减轻了后续污泥处理工序的负荷.随着超声处理污泥比例的增加,污泥体积指数SVI持续增大,但是超声污泥比例不超过10%对污泥沉降性能影响不大.因此,在超声强化污水生物处理工艺中,可采用强度0.3W/cm2超声波每隔8h取反应器中的10%的活性污泥辐照10min后再返回反应器,来提高反应器的生物处理效率.

关键词：低强度超声波活性污泥超声辐照污泥比例 COD NH3-N MLSS our SVI

低强度超声波强化污水生物处理中超声辐照周期的优化选择

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环境科学 2006年第5期27卷 898-902页

作者：闫怡新刘红北京师范大学环境学院北京100875 北京航空航天大学环境工程系北京100083

为了对低强度超声波强化污水生物处理的重要工艺参数——超声辐照周期进行优化，采用城市污水处理厂的好氧活性污泥为试验材料，以好氧呼吸速率（Oxygen Uptake Rate，our）和TTC。脱氢酶活性（2，3，5-triphenyl tetrazoliumehlorl ded... 详细信息

为了对低强度超声波强化污水生物处理的重要工艺参数——超声辐照周期进行优化，采用城市污水处理厂的好氧活性污泥为试验材料，以好氧呼吸速率（Oxygen Uptake Rate，our）和TTC。脱氢酶活性（2，3，5-triphenyl tetrazoliumehlorl dedehydrogenase activity，TTCDHA）为指标，研究了频率35kHz、强度0．3W／cm^2的超声波辐照10min后0～48h污泥活性的变化规律，发现超声辐照处理后8h污泥活性达到最大值，24h后超声波的强化作用基本消失．随后分别以8h和24h为超声辐照周期，进行了反复超声辐照处理试验．结果表明，当采用超声辐照周期为8h时，第2次超声辐照后污泥的活性就开始明显下降，3次辐照后污泥的活性下降到对照的一半；当采用超声辐照周期24h时，每次超声辐照后污泥活性依然有所升高，但是随着超声辐照次数增加，其升高的幅度逐渐降低．考虑到设备投资及处理效果稳定性，应采用8h的超声处理周期，每次只处理反应器内一定比例的污泥以避免反复超声引起的污泥活性下降．根据上述现象分析了低强度超声波改善污泥活性的机理．

关键词：低强度超声波强化生物处理活性污泥 our TTC-DHA 辐照周期

Tunable Bistability in the Goos–H?nchen Effect with Nonlinear Graphene

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Chinese Physics Letters 2019年第6期36卷 33-36页

作者：刘彬彬马普娟於文静徐亚东高雷 School of Physical Science and Technology & Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University Jiangsu Key Laboratory of Thin Films Soochow University

We present a planar model system of a silica covered with a monolayer of nonlinear graphene to achieve a tunable Goos–H?nchen(GH) shift in the terahertz range. It is theoretically found that the transition between a negative shift and a large positive one can be realized by altering the intensity of incident light. Moreover, by controlling the chemical potential of graphene and the incident angle of light, we can further control the tunable GH shift dynamically. Numerical simulations for GH shifts based on Gaussian waves are in good agreement with our theoretical calculations.

关键词： Goos controlling Gaussian shift can our GH It

Contactless Microwave Detection of Shubnikov–De Haas Oscillations in Three-Dimensional Dirac Semimetal ZrTe_5

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Chinese Physics Letters 2019年第6期36卷 49-52页

作者：武敏张红伟朱相德陆建伟郑国林高文帅韩玉岩周建辉宁伟田明亮 Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field Laboratory Chinese Academy of Sciences Department of Physics University of Science and Technology of China Department of Physics Shaanxi University of Science and Technology School of Science RMIT University Department of Physics School of Physics and Materials Science Anhui University

We report Shubnikov–de Haas(SdH)oscillations of a three-dimensional(3D) Dirac semimetal candidate of layered material ZrTe_5 single crystals through contactless electron spin resonance(ESR)measurements with the magnetic field up to 1.4 T.The ESR signals manifest remarkably anisotropic characteristics with respect to the direction of the magnetic field,indicating an anisotropic Fermi surface in ZrTe_5.Further experiments demonstrate that the ZrTe_5 single crystals have the signature of massless Dirac fermions with nontrivialBerry phase,key evidence for 3D Dirac/Weyl fermions.Moreover,the onset of quantum oscillation of our ZrTe_5 crystals revealed by the ESR can be derived down to 0.2 T,much smaller than the onset of SdH oscillation determined by conventional magnetoresistance measurements.Therefore,ESR measurement is a powerful tool to study the topologically nontrivial electronic structure in Dirac/Weyl semimetals and other topological materials with low bulk carrier density.

关键词： Dirac Microwave Haas ESR spin down tool our