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Visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)

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Chinese Chemical Letters 2024年第7期35卷 281-284页

作者： Tian-yu Gao Xiao-Yan Mo shu-Rong Zhang yuan-Xu Jiang shu-Ping Luo Jian-Heng Ye Da-Gang yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Herein, we report the first visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)to synthesize hydroxy acid derivatives. A variety of valuable β-, γ-, δ-, ε–hydroxy acid derivatives are obtained in moderate to high yields under mild conditions. This protocol shows noteworthy functionalgroup compatibility, high chemo-and regioselectivities under transition-metal-free conditions with an inexpensive organo-dye as photosensitizer. Mechanistic studies indicate that the benzylic carbanion is generated as an intermediate via the sequential single electron transfer(SSET) process.

关键词： Carbon dioxide Epoxides Visible-light photoredox catalysis Hydroxy acid Sequential single electron transfer

Theoretical insights into efficient oxygen evolution reaction using non-noble metal single-atom catalysts on W2CO2 MXene

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Rare Metals 2024年第10期43卷 5082-5094页

作者： Jing-yu Zhou Zhi-Cheng Han shu Zhao Tao Yang Da-Zhou Yan Hai-Jun yu Institute of Advanced Battery Materials and Devices College of Materials Science and EngineeringBeijing University of Technology Key Laboratory of Advanced Functional Materials Ministry of EducationBeijing University of Technology China ENFI Engineering Corporation National Engineering Research Center of Silicon-Based Materials Manufacturing Technology

The pursuit of highly active oxygen evolution reaction （OER） catalysts,especially those free of noble metals,is a focal point in fuel cell *** extensive density functional theory calculations,this study designed and evaluated the activity and stability of singleatom catalysts （SACs） composed of 3d,4d and 5d transition metals supported on tungsten-based MXene for OER *** highlighted the exceptional OER performance of Ni@W2CO2,Rh@W2CO2and Pt@W2CO2,displaying remarkably low overpotentials The catalytic activity of TM@W2CO2SACs exhibited a robust correlation with surface properties,particularly the d-band center index and surface work *** Ni@W2CO2,Rh@W2CO2and Pt@W2CO2emerged as promising candidates for OER and oxygen reduction reaction （ORR） bifunctional catalysis,while Pt@W2CO2and Rh@ W2CO2showed high potential for OER and hydrogen evolution reaction （HER） bifunctional catalysis The effectiveness of tungsten-based MXene as a substrate for non-noble-metal SACs marks a breakthrough in OER catalyst design,driving advancements towards sustainable energy solutions and addressing critical challenges in energy conversion and storage.

关键词： Density functional theory MXene Non-noble metal Oxygen evolution reaction Single-atom catalysts

Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu Qian-Qian Shi yu-Feng Meng Yong Zhou Li-Bo Mao shu-Hong yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

Strategies to advance thermoelectric performance of PbSe and PbS materials

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Rare Metals 2024年第9期43卷 4099-4114页

作者： Zheng-Hao Hou Xin Qian Qiu-juan Cui shu-Fang Wang Li-Dong Zhao Shijiazhuang Key Laboratory of Low Carbon Energy Materials College of Chemical EngineeringShijiazhuang UniversityShijiazhuang 050035China Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Thermoelectric materials possess the unique capability to convert thermal energy into electric energy and vice versa,making them promising for waste heat recovery and efficient cooling ***,extensively investigated thermoelectric materials such as Bi2Te3,PbTe and GeTe exhibit superior thermoelectric properties at room temperature and medium temperature ***,the broad application of these thermoelectric materials has been impeded by the high cost and restricted accessibility of Te and Ge in the earth's *** the past few years,researchers have shown increasing interest in PbSe-and PbS-based materials,primarily attributed to their abundant elemental supply and relatively low *** assessment of research progress and a comprehensive overview of optimization strategies in time can significantly contribute to further improving the thermoelectric *** strategies include optimizing carrier concentration(aliovalent doping,dynamic doping and defect state),enhancing density-of-state effective mass(band convergence,band flattening and energy filtering effect),optimizing carrier mobility(band sharpening and band alignment)and reducing lattice thermal conductivity(all-scale hierarchical defect structures designing).This systematic summary and analysis provide novel insights and perspectives for the development of thermoelectric materials.

关键词： PbSe and PbS thermoelectric materials Carrier concentration Density-of-state effective mass Carrier mobility Lattice thermal conductivity

The guest CH_(3)CN molecule triggers solid-state photochromism in a Cu_(2)I_(2)-based MOF for advanced time-dependent encryption and inkless erasable printing

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Chinese Chemical Letters 2024年第3期35卷 532-537页

作者： Meng-juan Wang Bo Li Yong-Li Wei shu-Na Zhao shuang-Quan Zang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China College of Chemistry and Pharmaceutical Engineering Nanyang Normal UniversityNanyang 473061China

It remains a big challenge to develop solid-state stimuli-responsive materials for time-dependent information encryption and inkless erasable printing with long retention ***,a 2D Cu_(2)I_(2)-based MOF with photoresponsive spiropyran(SP)groups orderly installed on its skeleton is *** structural isomerization from SP to colored merocyanine(MC)form can be triggered by removing the CH_(3)CN ***,the degree of structural isomerization and the retention time can be adjusted by controlling the amount of CH_(3)CN guests,exhibiting dynamic photochromic behavior with multicolor states and tunable retention *** on these advantages,time-dependent information encryption is successfully ***,the long retention time(>72 h)of the MC form under daylight conditions in the CH_(3)CN-removed Cu_(2)I_(2)-based MOF and good repeatability make it promising in various applications,such as temporary calendars,price-cards,billboards,and reusable identity *** work provides a novel design strategy to fabricate multi-functional MOF-based smart materials for challenging applications of time-dependent information encryption and inkless erasable printing.

关键词： Stimuli-responsive materials Spiropyran Solid-state photochromism Time-dependent encryption Inkless erasable printing

One-dimensional molecular co-crystal alloys capable of full-color emission for low-loss optical waveguide and optical logic gate

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Aggregate 2024年第1期5卷 299-308页

作者： Zhenhong Qi yu-juan Ma Dongpeng Yan Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryKey Laboratory of Radio-pharmaceuticals Ministry of EducationBeijing Normal UniversityBeijingChina

The luminescence color of molecule-based photoactive materials is the key to the applications in lighting and optical *** continuous regulation of emission color in molecular systems is highly desirable but still remains a challenge due to the individual emission band of purely organic ***,a novel alloy strategy based on molecular co-crystals is *** adjusting the molar ratio of pyrene(Py)and fluorathene(Flu),three types of molecular co-crystal alloys(MCAs)assemblies are prepared involving Py-Flu-OFN-x%,Py-Flu-TFP-x%,Py-Flu-TCNB-x%.Multiple energy level structure and Förster resonance energy transfer(FRET)process endow materials with tunable full-spectra emission color in visible ***,these MCAs and co-crystals can be successfully applied to low optical loss waveguide and optical logic gate by virtue of all-color luminescence from blue across green to red,together with smooth surface of onedimensional microrods,which show promising applications as continuous light emitters for advance photonics applications.

关键词： full-color emission microrods molecular co-crystal optical waveguide organic alloys

Research progress of ferroptosis regulating lipid peroxidation and metabolism in occurrence and development of primary liver cancer

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2335-2349页

作者： yu-Jie shu Bo Lao Ying-Yang Qiu Department of Gastroenterology Yinzhou District Second HospitalNingbo 315199Zhejiang ProvinceChina Yong Loo Lin School of Medicine National University of SingaporeSingapore 119077Singapore

As a highly aggressive tumor,the pathophysiological mechanism of primary liver cancer has attracted much *** recent years,factors such as ferroptosis regulation,lipid peroxidation and metabolic abnormalities have emerged in the study of liver cancer,providing a new perspective for understanding the development of liver *** regulation,lipid peroxidation and metabolic abnormalities play important roles in the occurrence and development of liver *** regulation of ferroptosis is involved in apoptosis and necrosis,affecting cell survival and *** peroxidation promotes oxidative damage and promotes the invasion of liver cancer *** abnormalities,especially the disorders of glucose and lipid metabolism,directly affect the proliferation and growth of liver cancer *** of ferroptosis regulation and lipid peroxidation may help to discover new therapeutic targets and improve therapeutic *** understanding of metabolic abnormalities can provide new ideas for the prevention of liver cancer,and reduce the risk of disease by adjusting the metabolic *** review focuses on the key roles of ferroptosis regulation,lipid peroxidation and metabolic abnormalities in this process.

关键词： Ferroptosis Lipid peroxidation Primary liver cancer Lipid metabolism Review

Quantum support vector machine for multi classification

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Communications in Theoretical Physics 2024年第7期76卷 57-62页

作者： Li Xu Xiao-yu Zhang Ming Li shu-qian Shen College of Science China University of PetroleumQingdao 266580China

Classical machine learning algorithms seem to be totally incapable of processing tremendous data,while quantum machine learning algorithms could deal with big data unhurriedly and provide exponential acceleration over classical *** this paper,we propose two quantum support vector machine algorithms for multi *** is the quantum version of the directed acyclic graph support vector *** other one is to use the Grover search algorithm before measurement,which amplifies the amplitude of the phase storing of the classification *** k classification,the former provides quadratic reduction in computational complexity when *** latter accelerates the training speed significantly and more importantly,the classification result can be read out with a probability of at least 50%using only one *** conduct numerical simulations on two algorithms,and their classification success rates are 96%and 88.7%,respectively.

关键词： quantum support vector machine quantum feature mapping Grover search algorithm

Extraction method of typical IEQ spatial distributions based on low-rank sparse representation and multi-step clustering

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Building Simulation 2024年第6期17卷 983-1006页

作者： yuren Yang Yang Geng Hao Tang Mufeng yuan juan yu Borong Lin School of Architecture Tsinghua UniversityBeijingChina Key Laboratory of Eco Planning&Green Building Ministry of EducationTsinghua UniversityBeijingChina

Indoor environment quality(IEQ)is one of the most concerned building performances during the operation *** non-uniform spatial distribution of various IEQ parameters in large-scale public buildings has been demonstrated to be an essential factor affecting occupant comfort and building energy ***,IEQ sensors have been widely employed in buildings to monitor thermal,visual,acoustic and air ***,there is a lack of effective methods for exploring the typical spatial distribution of indoor environmental quality parameters,which is crucial for assessing and controlling non-uniform indoor *** this study,a novel clustering method for extracting IEQ spatial distribution patterns is ***,representation vectors reflecting IEQ distributions in the concerned space are generated based on the low-rank sparse ***,a multi-step clustering method,which addressed the problems of the“curse of dimensionality”,is designed to obtain typical IEQ distribution patterns of the entire indoor *** proposed method was applied to the analysis of indoor thermal environment in Beijing Daxing international airport *** a result,four typical temperature spatial distribution patterns of the terminal were extracted from a four-month monitoring,which had been validated for their good *** typical patterns revealed typical environmental issues in the terminal,such as long-term localized overheating and temperature increases due to a sudden influx of *** extracted typical IEQ spatial distribution patterns could assist building operators in effectively assessing the uneven distribution of IEQ space under current environmental conditions,facilitating targeted environmental improvements,optimization of thermal comfort levels,and application of energy-saving measures.

关键词： indoor environment quality(IEQ) thermal environment spatial distribution temperature field low-rank sparse representation(LRSR) clustering