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Study on B_d→φK_s Decay in EDQS Model

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Communications in Theoretical Physics 2009年第11期52卷 919-923页

作者： WANG Shuai-Wei li Gen-quan yang Xing-Qiang HUANG Jin-Shu Department of Physics Nanyang Normal University Nanyang 473061 China

We study Bd → φKs decay in extra down-type quarks （EDQS） model with a non-universal Z boson associated with flavor changing neutral currents （FCNCs） at the tree level. With the up-to-date experimental data of Br（Bd → φKs）, SCKs, and ACKs, we derive the bounds on the Z-b-s coupling parameter ｜Ubs ｜ and the new weak phase φ, using the constrained parameter spaces, we finally give predictions for Bd → φφ decay, which could be tested at the Fermilab Tevatron and the LHC-b experiments.

关键词： EDQS modell CP asymmetry QCD factorization

Distributed Harmonic Power Sharing with Voltage Distortion Suppression in Islanded Microgrids Considering Non-linear Loads

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 117-128页

作者： Guannan Lou Shanlin li Wei Gu quan yang School of Electrical Engineering Southeast UniversityNanjingJiangsu 210096China the Jiangsu Provincial Key Laboratory of Smart Grid Technology and Equipment Southeast University Dongguan Power Supply Bureau of Guangdong Power Grid Company Guangdong 523000China

In contemporary power grids or microgrids,harmonic distortion has emerged as one of the critical power quality issues for utility power grids,which has escalated especially due to the high penetration of power-electronic-converter-interfaced distributed generation(DG).This paper first illustrates the prevalent dispute revolving around the harmonic power sharing and distortion restraint,and subsequently proposes a consensusbased framework that facilitates an accurate sharing of harmonics among multi-DGs connected in parallel,with an effective suppression of the output voltage *** with the majority of existing studies addressing the issue of voltage harmonics at the point of common coupling(PCC),our method primarily emphasizes on the output voltage distortion since the power quality requirement for certain local critical loads is often known to be *** the help of adaptive regulation,the overall distortion produced at the output terminals of DGs can be retained within an acceptable *** working principle of the proposed control method,which is not only easy to implement but also independent of model parameters,is further described in *** the small-signal dynamic model,the system stability and robustness are *** hardware-in-the-loop(HIL)simulations aid in determining the outcome of the proposed strategy in microgrid control.

关键词： Distributed generation droop control harmonic power sharing microgrid voltage distortion mitigation

A novel and green synthesis of indolone-N-amino acid derivatives via the Passerini three-component reactions in water

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Chinese Chemical Letters 2016年第3期27卷 345-348页

作者： Rong-Kun li quan-li yang Yi liu Dong-Wei li Nian-Yu Huang Ming-Guo liu Hubei Key Laboratory of Natural Products Research and Development College of Biological and Pharmaceutical SciencesChina Three Gorges University

A green Passerini three-component reaction of 2-（4-oxo-4,5,6,7-tetrahydro-1H-indol-1-yl）acetic acid with alkyl or aryl isocyanides and aldehydes was reported under aqueous conditions at 35 ℃ for 1 h, and21 indolone-N-amino acid derivatives were prepared in high yields of 42%–99%. Their structures were characterized by IR, ESI–MS, NMR and elemental analysis, and the possible mechanisms have been also proposed. The highly efficient and eco-friendly method provides a facile access to a library of indoloneN-amino acid derivatives for future research on bioactivity screening.

关键词： Passerini three-component reaction Indolone-N-amino acid Green synthesis Heterocycles Isocyanide

Controllable CPL response driven by achiral UV-photosensitive dichroic dye through cholesteric liquid crystals

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Science China Chemistry 2024年第4期67卷 1250-1255页

作者： Yihan Chen yang li Hang li Lulu li Yiwu quan Yixiang Cheng State Key Laboratory of Analytical Chemistry for life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of High-Performance Polymer Material and Technology of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Versatile stimuli-responsive circularly polarized luminescent(CPL)materials have potential applications in information storage,security encryption,and intelligent *** this study,the Z/E isomerization of ultraviolet(UV)-photosensitive achiralα-cyanostilbene derivative was used as an achiral dichroic dye(Switch)to drive the controllable CPL-active response in cholesteric liquid crystals(CLCs).Under irradiation by 365 nm UV light,the resulting CLCs-Z-Switch underwent a Z-to-E configuration isomerization as CLCs-E-Switch,accompanied by a decrease in its dichroic order parameter(SFvalue)from 0.15to *** the quantum yield(QY)of CLCs-E-Switch increased from 8.1%(CLCs-Z-Switch)to 16.8%,the corresponding glumvalues of CPL emission decreased from+0.55/-0.57 to+0.37/-0.39 due to a decrease in the order of helical arrangement of E-Switch in E7 *** study enables photosensitive CLCs-Switch to be applied for optical information storage devices.

关键词： circularly polarized luminescent photosensitive dichroic dye cholesteric liquid crystals chiral induction

Design and modification of metal sulfide-based catalysts for lithiumsulfur batteries

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Particuology 2024年第3期86卷 86-100页

作者： Yufei Zhao Chuannan Geng li Wang Haotian yang Wei Lv quan-Hong yang Nanoyang Group State Key Laboratory of Chemical EngineeringSchool of Chemical Engineering and TechnologyNational Industry-Education Integration Platform of Energy Storageand Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin UniversityTianjin300072China Shenzhen Geim Graphene Center Engineering Laboratory for Functionalized Carbon MaterialsTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen518055China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou350207China

Metal sulfide(MS)have good conductivity,strong adsorption ability,and excellent catalytic activity for the conversion of sulfur species,and thus,show great promise as the catalysts in lieS ***,the relationship between their properties and electrochemical performance is still ***,further in-depth discussions are required to improve their design in li-S *** review systematically summarizes the basic structural and electrochemical properties of MSs and highlights the advantages that guarantee them as high-performance catalysts in li-S ***,various modification strategies for MSs to enhance the catalytic activity,efficiency,and stability are also *** last,future opportunities for MS catalysts in li-S batteries are proposed.

关键词： lithium-sulfur battery Metal sulfide Catalysis

Strip flatness prediction of cold rolling based on ensemble methods

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Journal of Iron and Steel Research International 2024年第1期31卷 237-251页

作者： Wu-quan yang Zhi-ting Zhao liang-yu Zhu Xun-yang Gao li Wang School of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang110142LiaoningChina

Aiming at the problem of insufficient prediction accuracy of strip flatness at the outlet of cold tandem rolling,the prediction performance of strip flatness based on different ensemble methods was studied and a high-precision prediction ensemble model of strip flatness at the outlet was ***,based on linear regression(LR),K nearest neighbors(KNN),support vector regression,regression trees(RT),and backpropagation neural network(BPN),bagging,boosting,and stacking ensemble methods were used for ensemble ***,three existing ensemble models,i.e.,random forest,extreme random tree(ET)and extreme gradient boosting,were used to conduct experiments and compare the *** research shows that bagging,boosting,and stacking three ensemble methods have the most significant improvement in the prediction accuracy of the regression trees model,which is increased by 5.28%,6.51%,and 5.32%,*** the same time,the stacking ensemble method improves both the simple model and the complex model,and the improvement effect on the simple base model is the greatest,which is 4.69%higher than that of the base model *** all of the ensemble models,the stacking ensemble model of level-1(ET,AdaBoost-RT,LR,BPN)paired with level-2(LR)was discovered to be the best model(EALB-LR)and can be further studied for industrial applications.

关键词： Tandem cold rolling Flatness prediction Machine learning Ensemble method

Interfacial built-in electric field and crosslinking pathways enabling WS_(2)/Ti_(3)C_(2)T_(x) heterojunction with robust sodium storage at low temperature

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Journal of Energy Chemistry 2024年第2期89卷 635-645,I0014页

作者： Jiabao li Shaocong Tang Jingjing Hao quan Yuan Tianyi Wang likun Pan Jinliang li Shenbo yang Chengyin Wang College of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002JiangsuChina Shanghai Key Laboratory of Magnetic Resonance School of Physics and Electronic Science East China Normal UniversityShanghai 200241China Siyuan Laboratory Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy MaterialsGuangdong Provincial Key Laboratory of Nanophotonic ManipulationDepartment of PhysicsJinan UniversityGuangzhou 510632GuangdongChina Hongzhiwei Technology(Shanghai)CO.LTD Shanghai 200241China

Developing efficient energy storage for sodium-ion batteries(SIBs)by creating high-performance heterojunctions and understanding their interfacial interaction at the atomic/molecular level holds promise but is also ***,sluggish reaction kinetics at low temperatures restrict the operation of SIBs in cold ***,cross-linking nanoarchitectonics of WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,featuring built-in electric field(BIEF),have been developed,employing as a model to reveal the positive effect of heterojunction design and BIEF for modifying the reaction kinetics and electrochemical ***,the theoretical analysis manifests the discrepancy in work functions leads to the electronic flow from the electron-rich Ti_(3)C_(2)T_(x) to layered WS_(2),spontaneously forming the BIEF and“ion reservoir”at the heterogeneous ***,the generation of cross-linking pathways further promotes the transportation of electrons/ions,which guarantees rapid diffusion kinetics and excellent structure ***,superior sodium storage performance is obtained for the WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,with only 0.2%decay per cycle at 5.0 A g^(-1)(25℃)up to 1000 cycles and a high capacity of 293.5 mA h g^(-1)(0.1A g^(-1)after 100 cycles)even at-20℃.Importantly,the spontaneously formed BIEF,accompanied by“ion reservoir”,in heterojunction provides deep understandings of the correlation between structure fabricated and performance obtained.

关键词： WS_(2)/Ti_(3)C_(2)T_(x)heterojunction Built-in electric field Ion reservoir Reaction kinetics Sodium storage performance at low temperature

Response of nitrogen-cycling key functional genes and microbial communities in paddy soils to microplastics combined with antibiotics

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Science China Technological Sciences 2024年第10期67卷 3132-3135页

作者： liN liJun yang GuiQin quan XiaoYun ZHOU ZhuoYi CHEN XiaoChun ZHUANG li Guangdong Key Laboratory of Environmental Pollution and Health College of Environment and ClimateJinan University

Nitrogen（N）, an essential nutrient element in paddy soils, is crucial for rice production. N-cycling in soils is mainly mediated by microorganisms; thus,the potential of N-cycling can be evaluated based on the structure of microbial communities that participated in the N-cycling processes. In paddy soils, biological nitrification and denitrification are the primary processes for N fertilizer use, N loss, and N2O emission.

关键词： AMMONIA-OXIDIZING BACTERIA ARCHAEA

Bio-soft matter derived from traditional Chinese medicine:Characterizations of hierarchical structure,assembly mechanism,and beyond

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Journal of Pharmaceutical Analysis 2024年第6期14卷 823-839页

作者： Guiya yang Yue liu Yuying Hu Yue Yuan Yunan Qin quan li Shuangcheng Ma School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing102488China Institute for Control of Chinese Traditional Medicine and Ethnic Medicine National Institutes for Food and Drug ControlBeijing100050China Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine School of Chinese Materia MedicaTianjin University of Traditional Chinese MedicineTianjin301617China Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesCollege of Chemistry and Chemical EngineeringHubei UniversityWuhan430062China

Structural and functional explorations on bio-soft matter such as micelles,vesicles,nanoparticles,aggregates or polymers derived from traditional Chinese medicine(TCM)has emerged as a new topic in the field of *** discovery of such cross-scaled bio-soft matter may provide a unique perspective for unraveling the new effective material basis of TCM as well as developing innovative medicine and *** the rapid rise of TCM-derived bio-soft matter,their hierarchical structure and assembly mechanism must be unambiguously probed for a further in-depth understanding of their pharmacological *** this review,the current emerged TCM-derived bio-soft matter assembled from either small molecules or macromolecules is introduced,and particularly the unambiguous elucidation of their hierarchical structure and assembly mechanism with combined electron microscopic and spectroscopic techniques is *** pros and cons of each technique are also *** future challenges and perspective of TCM-derived bio-soft matter are outlined,particularly the requirement for their precise in situ structural determination is highlighted.

关键词： Electron microscopy Spectroscopy Traditional Chinese medicine Bio-soft matter Structural characterization