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Stereospecific Synthesis of the Skeleton of the Antitumor Marine Natural Product Et-743

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Stereospecific Synthesis of the Skeleton of the Antitumor Ma...

Molecular mechanism for the unusual enhancement of the second-step chemiluminescence production from the carcinogenic tetrabromohydroquinone and H2O_(2)

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作者： liu, zhan-zhu tang, ye-feng wang, ye chen, shi-zhi (Institute of Materia Medina , Peking Union Medical College & Chinese Academy of Medical Sciences , Beijing 100050)

＜正＞ Ecteinascidin 743 （Et-743） is an exceedingly potent antitumor agent isolated from the marine tunicate Ecteinascidia turbinate . As its structurally simplified version, Phthalascidin was found to retain the cytotoxicity of the natural product. Their novel structures, impressive biological activities and difficult availabilities conspire to render the attractive targets for total synthesis. Corey and co-workers completed the total synthesis of Et-743 and phtha-

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Journal of Environmental Sciences 2024年第7期141卷 330-342页

作者： Zi-Han wang Chun-Hua Huang zhi-Sheng liu Li Mao Ben-zhan zhu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environment and Resources University of Chinese Academy of SciencesBeijing 100049China

We have found recently that two-step intrinsic hydroxyl radical(·OH)-dependent chemiluminescence(CL)could be produced by carcinogenic tetrahaloquinone and H_(2)O_(2).However,the first-step CL was too fast to clearly detect the stepwise generation of·OH and CL,and to distinguish the exact dividing point between the first-step and second-step *** we found that,extremely clear two-step intrinsic CL could be produced by the relative slow reaction of tetrabromohydroquinone(TBHQ)with H_(2)O_(2),which was directly dependent on the two-step·OH ***,the second-step,but not the first-step CL production of TBHQ/H_(2)O_(2)(CRET donor)was markedly enhanced by fluorescein(a typical xanthene dye,CRET acceptor)through a unique chemiluminescence resonance energy transfer(CRET)*** novel CRET system of TBHQ/H_(2)O_(2)/fluorescein was successfully applied for the sensitive detection of TBHQ with the detection limit as low as 2.5μmol/*** findings will help to develop more sensitive and highly efficient CL or CRET systems and specific CL sensor to detect the carcinogenic haloquinones,which may have broad environmental applications.

关键词： Two-step chemiluminescence Bromohydroquinone Hydrogen peroxide Hydroxyl radical CRET

Synthesis and optical properties of highly efficient Na_(3)KMg_(7)(PO_(4))_(6):Eu^(2+)blue phosphor for full-spectrum white-light-emitting diodes:The role of Li_(2)CO_(3)flux

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Journal of Rare Earths 2024年第7期42卷 1217-1223,I0001页

作者： Zihao wang Sisi Liang chenyang zhan Kunyuan Xu Jie Hu Dejian chen Liping Song Haomiao zhu School of Physics and Materials Science Nanchang UniversityNanchang330000China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Research Center of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen361021China

Full-spectrum phosphor-converted white-light-emitting diodes(pc-WLED)are emerging as a mainstream technology in semiconductor ***,high-performance blue phosphor which can be excited efficiently by a 400 nm NUV diode chip is still ***,we present a blue-emitting Na_(3)KMg_(7)(PO_(4))6:Eu^(2+)phosphor synthesized by the solid-reaction ***,we find that the using of Li_(2)CO_(3)as flux can significantly improve the crystal quality and thus the emission efficiency of the ***,the excitation peak of the phosphor shifts from 365 to 400 nm,which is pivotal for efficient NUV(400 nm)diode chip *** practical Eu^(2+)concentration is also enhanced by using Li_(2)CO_(3)as flux,and the absorption efficiency is greatly *** phosphor exhibits superior PL thermal stability,namely retains 94%integrated photoluminescence intensity at 150℃of that at 25℃.As a result,the optimized phosphor shows an emission band peaked at 437 nm with a bandwidth of 40 nm and a high external photoluminescence quantum yield of 51.7%.Finally,a pc-WLED was fabricated by using NKMPO:Eu^(2+)blue,Sr_(2)SiO_(4):Eu^(2+)green,CaAlSiN_(3):Eu^(2+)red phosphors,and a 400 nm NUV diode *** shows a high color rendering index of R_(a)=96.4 and a correlated color temperature of 4358 *** results prove that NKMPO:Eu^(2+)is a promising blue phosphor for full-spectrum WLED based on NUV diode chips.

关键词： Eu^(2+) Blue phosphor Na_(3)KMg_(7)(PO_(4))_(6) Full-spectrum white LEDs Rare earths

A bibliometric analysis of molybdenum-based nanomaterials in the biomedical field

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Tungsten 2024年第1期6卷 17-47页

作者： zhi-Qiang wang Ya-Wen Pan Jing Wu Hong-Bin Qi Shuang zhu zhan-Jun Gu School of Science China University of GeosciencesBeijing 100083China CAS Key Laboratory for Biomedical Eff ects of Nanomaterials and Nanosafety Institute of High Energy PhysicsBeijing 100049China CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology of ChinaChinese Academy of SciencesBeijing 100190China College of Materials Science and Optoelectronic Technology University of Chinese Academy of SciencesBeijing 100049China

Molybdenum(Mo)-based nanomaterials have been widely used in biomedical fields due to their various nanostructures and unique physical/chemical *** various reviews have described the development of Mo-based materials in the biomedical field,an objective and comprehensive summary and analysis of research trends in this field is still ***,we used the bibliometric analysis method to analyze all relevant literature on the biological application of Mobased nanomaterials in recent ***,we use bibliometric tools to analyze the dataset by year,country/region,institution and research hotspot to obtain the research ***,based on objectively identified research hotspots,the biomedical applications of Mo-based nanomaterials are reviewed comprehensively,mainly including sensors,cancer imaging/therapy and antibacterial ***,we discussed the application prospects and challenges of Mo-based *** article provides a new perspective to understand the current research progress and further promote the development of Mobased nanomaterials in biomedical research.

关键词： Molybdenum Nanomaterial Biomedicine Bibliometric analysis

Single-atom Zn confined in hierarchical hollow microstructure as an acid/base-resistant microwave absorption materials

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Nano Research 2024年第8期17卷 6785-6794页

作者： Yue Lou Jiao Li Xiaokun Li Zhenyu zhu zhan shi Biao Xu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China

Developing acid/base-resistant and low-price microwave-absorbing materials with lighter weight is highly desired for practical applications in extreme ***,we demonstrate the successful synthesis of the N-doped porous carbon(NC)material with hierarchical pore structure by the spray pyrolysis *** large specific surface area(SBET=707.53 m^(2)·g^(−1))of materials enables multiple scattering of incident electromagnetic waves,and N doping greatly enhances the electrical conductivity of the ***,single-atom Zn can adjust the local electronic structure of adjacent sites such as carbon and nitrogen atoms,induce the center of polarization,and thus change the dielectric and electronic properties of the host *** porous carbon coating of single-atom Zn avoids the deterioration of electromagnetic parameters caused by the accumulation of magnetic particles under high-temperature *** the same time,they can also be used in various complex environments,such as acidic and basic ***,NC-1000,with high surface area,low density,and good chemical stability,obtained a minimum reflection loss(RLmin)of−50.5 dB and an effective absorption bandwidth(EAB)exceeding 5.1 GHz at the thickness of 1.9 *** soaking in the strong acid and base solution,the electromagnetic wave absorption performance of the material decreased by<15%.Widely available raw materials and a simple preparation scheme are expected to expedite industrial mass production for this novel type of materials.

关键词： hierarchical hollow microstructure microwave absorption metal-organic framework(MOF) impedance matching singleatom Zn acid/base-resistant

Nano-engineered catalysts for high-performance oxygen reduction reaction

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Chinese Chemical Letters 2024年第10期35卷 510-516页

作者： Kunsong Hu Yulong zhang Jiayi zhu Jinhua Mai Gang liu Manoj Krishna Sugumar Xinhua liu feng zhan Rui Tan School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Energy Innovation Centre Warwick Manufacture GroupUniversity of WarwickCoventry CV47ALUnited Kingdom School of Transportation Science and Engineering Beihang UniversityBeijing 100191China IDTECH(Suzhou)Co. Ltd.Suzhou 215217China College of Mechatronical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001China

The efficient energy conversion of fuel cells is greatly constrained by the slow oxygen reduction reac tion(ORR)kinetics,which necessitates the use of highly active metal catalysts such as platinum(Pt).The critical challenge limiting large-scale usage of Pt is the capital cost that can be addressed through a pro totypical approach by embedding metal nanoparticles(NPs),e.g.,Pt NPs,in the conductive framework However,previously reported embedding approaches are sophisticated and suffer from limited yields leading to higher chemical process costs and remaining distant from commercial ***,we re port a facile,cost-effective and time-efficient structural tuning approach to synthesizing ultrafine Pt NP impregnated within a conductive and highly porous carbon framework via a microwave-assisted polyo reduction *** NPs with a uniform size of~2.27 nm can be successfully integrated within the pore of the carbon framework,enabling homogeneous *** from these highly dispersed and ultrafine Pt NPs,the electrochemical surface area(ECSA)is improved to 142.98 m^(2)/gPt,2.25 times highe than that of the commercial counterpart(63.52 m^(2)/gPt).Furthermore,our structurally optimized catalys composite features a remarkably catalytic activity with a high half-wave potential(E_(1/2))of 0.895 V and an improved mass activity(MA)of 0.2289 A/mgPt,2.39-fold improvement compared to the commercia *** addition,orthogonal experiments were designed to identify the key process parameter for fabricating Pt/C catalysts,offering insights for scaled-up and industrial production.

关键词： Fuel cells Oxygenreductionreaction Structural engineering Microwave method Ultrafine nanoparticles

Synergistically enhanced dielectric, insulating and thermally conductive performances of sandwich PMMA based dielectric films

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Progress in Natural Science:Materials International 2024年第3期34卷 591-597页

作者： Dongmei zhang Yufan Li Yuchao Li Zhonggui Sun Hanxue zhu Lujia Yang Yanhu zhan Yankai Li shi wang Jun-Wei Zha School of Mathematical Sciences Liaocheng University School of Materials Science and Engineering Liaocheng University State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications School of Chemistry and Biological Engineering University of Science and Technology Beijing

A tri-layered(B-G-B) dielectric films were simply prepared by alternatively spin-coating boron nitride/polymethylmethacrylate(BN/PMMA, B) and graphene nanosheets(GNS/PMMA, G) compound solutions. The structure, morphology, thermal conductivity, and particularly the dielectric and relaxation behaviors were systematically studied. Results showed that a good exfoliation and dispersion of BN and GNS can be simply achieved through intensive mechanical compounding with PMMA in the internal mixer. The dielectric constant and breakdown strength of the obtained 1-3-1(B-G-B) sandwich composite film reached 4.3(@1 kHz) and 458.6kV/mm, being 119 % and 113 % higher than that of pure PMMA, respectively. Furthermore, the overall thermal conductivity of sandwich 1-3-1 composite increased by 112 % due to the addition of thermally conductive BN and GNS. The sandwich design strategy provided an effective way of achieving good permittivity, high insulation, and improved thermal conductivity simultaneously, showing potential applications in the miniaturization and integration of electronic devices.

关键词： Sandwich structure Breakdown strength Thermal conductivity Dielectric constant Composites

Establishment of NaLuF_(4):15%Tb-based low dose X-PDT agent and its application on efficient antitumor therapy

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 599-610页

作者： Yi Tian zhiguang Fu Xiaosheng zhu Chunjing zhan Jinwei Hu Li Fan Chaojun Song Qian Yang Yu wang Mei shi Department of Radiation Oncology Xijing HospitalThe Fourth Military Medical UniversityXi’an 710032China Department of Oncology Air Force Medical CenterPLAThe Fourth Military Medical UniversityBeijing 100142China Department of Tumor Radiotherapy Air Force Medical CenterPLAThe Fourth Military Medical UniversityBeijing 100142China Department of Gastroenterology Air Force Hospital of Southern Theater CommandGuangzhou 510062China Department of Pharmaceutical Chemistry and Analysis School of PharmacyThe Fourth Military Medical UniversityXi’an 710032China School of Life Sciences Northwestern Polytechnical UniversityXi’an 710072China Institue of Materia Medica School of PharmacyThe Fourth Military Medical UniversityXi’an 710032China

X-ray excited photodynamic therapy(X-PDT)is the bravo answer of photodynamic therapy(PDT)for deep-seated tumors,as it employs X-ray as the irradiation source to overcome the limitation of light penetration ***,high X-ray irradiation dose caused organ lesions and side effects became the major barrier to X-PDT *** address this issue,this work employed a classic-al co-precipitation reaction to synthesize NaLuF_(4):15%Tb^(3+)(NLF)with an average particle size of(23.48±0.91)nm,which was then coupled with the photosensitizer merocyanine 540(MC540)to form the X-PDT system NLF-MC540 with high production of singlet *** system could induce antitumor efficacy to about 24%in relative low dose X-ray irradiation range(0.1-0.3 Gy).In vivo,when NLF-MC540 irradiated by 0.1 Gy X-ray,the tumor inhibition percentage reached 89.5%±5.7%.The therapeutic mechanism of low dose X-PDT was found.A significant increase of neutrophils in serum was found on the third day after *** immunohistochemical staining of tumor sections,the Ly6G^(+),CD8^(+),and CD11c^(+)cells infiltrated in the tumor microenvironment were *** the bilat-eral tumor model,the NLF-MC540 with 0.1 Gy X-ray irradiation could inhibit both the primary tumor and the distant tumor ***-tected by enzyme linked immunosorbent assay(ELISA),two cytokines IFN-γand TNF-αin serum were upregulated 7 and 6 times than negative control,*** by enzyme linked immune spot assay(ELISPOT),the number of immune cells attributable to the IFN-γand TNF-αlevels in the group of low dose X-PDT were 14 and 6 times greater than that in the negative control group,***,it conclude that low dose X-PDT system could successfully upregulate the levels of immune cells,stimulate the secretion of cy-tokines(especially IFN-γand TNF-α),activate antitumor immunity,and finally inhibit colon tumor growth.

关键词： X-ray excited photodynamic therapy singlet oxygen low dose X-Ray irradiation efficient antitumor therapy anti-tumor immunity

Recent advances in Fe-N-C-and Co-N-C-based materials as bifunctional electrocatalysts for oxygen reduction and oxygen evolution

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Science China Chemistry 2024年第4期67卷 1137-1160页

作者： Hui-Min Xu Hong-Rui zhu chen-Jin Huang zhi-Jie zhang Ting-Yu Shuai Qi-Ni zhan Gao-Ren Li College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Fe-nitrogen-carbon(Fe-N-C)-and Co-nitrogen-carbon(Co-N-C)-based electrocatalysts have been widely concerned because of their high OER/ORR activity,low metal cost,and simple *** exploration of Fe-N-C and Co-N-C single atombased catalysts with high activity and stability to overcome the slow kinetics of oxygen reduction and oxygen evolution reactions is also the key to the development of efficient electrolytic water,fuel cells,and rechargeable metal-air ***-N-C and Co-N-C single atom-based electrocatalysts have the advantages of a high utilization rate of metal atoms and high electrocatalytic activity,and are ideal catalysts for promoting electrochemical energy conversion and *** general principles of designing Fe-N-C and Co-N-C single atom-based electrocatalysts are reviewed in this ***,the strategies to improve the bifunctional catalytic activity and stability are ***,the challenges and prospects of Fe-N-C and Co-N-C single atom-based catalysts are well *** review will provide a reference for the directed optimization of Fe-N-C and Co-N-C single atom-based catalysts.

关键词： Fe-N-C Co-N-C single atom bifunctional oxygen electrocatalysts