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Tungsten oxide/nitrogen-doped carbon nanotubes composite catalysts for enhanced redox kinetics in lithium-sulfur batteries

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Chinese Journal of Chemical Engineering 2024年第3期67卷 58-67页

作者： Deqing He Zihao xie qian Yang Wei Wang Chao Su School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212100China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

The sluggish redox kinetics of polysulfides in lithium-sulfur(Li-S)batteries are a significant obstacle to their widespread adoption as energy storage ***,recent studies have shown that tungsten oxide(WO_(3))can facilitate the conversion kinetics of polysulfides in Li-S ***,we fabricated host materials for sulfur using nitrogen-doped carbon nanotubes(N-CNTs)and WO_(3).We used low-cost components and simple procedures to overcome the poor electrical conductivity that is a disadvantage of metal *** composites of WO_(3) and N-CNTs(WO_(3)/N-CNTs)create a stable framework structure,fast ion diffusion channels,and a 3D electron transport network during electrochemical reaction *** a result,the WO_(3)/N-CNT-Li2S6 cathode demonstrates high initial capacity(1162 mA·h·g^(-1) at 0.5℃),excellent rate performance(618 mA·h·g^(-1) at 5.5℃),and a low capacity decay rate(0.093%up to 600 cycles at 2℃).This work presents a novel approach for preparing tungsten oxide/carbon composite catalysts that facilitate the redox kinetics of polysulfide conversion.

关键词： Li-S batteries Composites Ion diffusion channels 3D electron transport network Redox kinetics

Inhibition of SIRT6 in prostate cancer reduces cell viability and increases sensitivity to chemotherapeutics

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Protein & Cell 2013年第9期4卷 702-710页

作者： Yewei Liu qian reuben xie Boshi Wang Jiaxiang Shao Tingting Zhang Tengyuan Liu Gang Huang Weiliang Xia School of Biomedical Engineering and Med-X Research Institute Shanghai Jiao Tong UniversityShanghai 200030China De partment of Nuclear Medicine Renji HospitalSh anghai Jiao Tong University School of MedicineShanghai 200127China C linical Stem Cell Center Renji HospitalSh anghai Jiao Tong University School of MedicineShanghai 200127China

SI RT6 is an important histone modifying protein that regulates DNA repair,telomere maintenance,energy me-tabolism,and target gene *** SIRT6 has been identifi ed as a tumor suppressor and is down-regulated in certain cancer types,but not in other *** deposited gene profi ling studies we found that SIRT6 was overexpressed in prostate tumors,compared with normal or paratumor prostate *** micro-array studies confi rmed the higher levels of SIRT6 in both prostate tumor tissues and prostate cancer cells than in their normal *** of SIRT6 in human prostate cancer cells led to sub-G1 phase arrest of cell cy-cle,increased apoptosis,elevated DNA damage level and decrease in BCL2 gene ***,SIRT6-de-fi ciency reduced cell viability and enhanced chemothera-peutics *** together,this study provides the fi rst evidence of SIRT6 overexpression in human prostate cancer,and SIRT6 regulation could be exploited for pros-tate cancer therapy.

关键词： SI RT6 overexpression prostate cancer th erapy

A multi-enzymatic cascade reaction for the synthesis of bioactive C-oligosaccharides

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Chinese Chemical Letters 2024年第6期35卷 451-455页

作者： Kebo xie qian Zhang Fei Ye Jungui Dai State Key Laboratory of Bioactive Substance and Function of Natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs and NHC Key Laboratory of Biosynthesis of Natural ProductsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

C-Oligosaccharides are rare in nature and possess diverse ***,their chemical synthesis faces many *** this work,enzymatic introduction of C-linked sugar chains to target aglycones was successfully achieved by multi-enzymatic cascade reactions.A C-glycosyltransferase from Aloe barbadensis was employed to introduce the first C-linked glucose and then a cyclomaltodextrin glucanotransferase from Bacillus licheniformis was used to extend the sugar chain.A total of twenty C-oligosaccharides with 2-6 sugars were synthesized from scale-up reactions and exhibited good water solubility and sodium-dependent glucose transporter 2(SGLT2)inhibitory ***,a glucoamylase was used to control the length of the sugar chain and the C-maltosides were efficiently *** findings not only expanded the structural diversity of C-oligosaccharides,but also provided a strategy for the modification of C-glycoside drugs to improve the druggability.

关键词： C-Oligosaccharides C-Glycosyltransferase Cyclomaltodextrin glucanotransferase Glucoamylase Enzymatic synthesis SGLT2 inhibitory activity

Progress and Challenges of Water-soluble NIR-II Organic Fluorophores for Fluorescence Imaging In vivo

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Chemical Research in Chinese Universities 2024年第2期40卷 190-201页

作者： xie Yuxin QIN Zuojia qian Ming REN Tianbing YUAN Lin State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082P.R.China

The small-molecule fluorophores for the second near-infrared(NIR-II,1000–1700 nm)window have attracted increasing attention in basic scientific research and preclinical practice owing to their deep-photo penetration,minimal physiological toxicity and simplicity of chemical ***,most of the reported small-molecule NIR-II fluorophores suffered from poor water solubility,which can easily cause organ *** addition,the aggregation caused by their poor water solubility in the aqueous solution would also result in weak fluorescence of these NIR-II ***,it is highly desirable and valuable to develop water-soluble small-molecule NIR-II fluorophores with excellent photophysical properties for high-contrast in vivo *** this review,we summarize the recent research advances in water-soluble small-molecule NIR-II fluorophores and highlight the representative bioimaging ***,the potential challenges and perspectives of water-soluble small-molecule NIR-II fluorophores are discussed as *** anticipate this review can help researchers to grab the latest information of water-soluble small-molecule fluorophores for NIR-II imaging,sequentially boosting their further development.

关键词： Organic fluorophore Fluorescent imaging Imaging reagent Fluorescent probe The second near-infrared(NIR-II)imaging

Yolk-shell FeSe_(2)@CoSe_(2)/FeSe_(2) heterojunction as anode materials for sodium-ion batteries with high rate capability and stability

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Journal of Materials Science & Technology 2024年第5期172卷 185-195页

作者： Liuyang Zhang Bicheng Zhu Difa Xu Zibao qian Ping xie Tao Liu Jiaguo Yu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China Hunan Key Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410022China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Sodium-ion batteries are promising candidates for large-scale grid storage systems and other *** foremost advantage derives from superior environmental credentials,enhanced safety as well as lower raw material costs than lithium-ion *** is still challenging to explore desirable anode *** this study,FeSe_(2)@CoSe_(2)/FeSe_(2),with a yolk-shell structure was prepared by ion exchange and *** FeSe_(2)@CoSe_(2)/FeSe_(2)prepared as anode material for sodiumion batteries exhibits excellent rate capability due to the synergistic effect of bimetallic selenides and the interfacial effect of the ***,it delivers high performance(510 mAh g^(-1)at 0.2 A g^(-1)),superior rate capa-bility(90%retention at 5 A g^(-1)),and good long-time cycling stability(78%capacity retention after 1800 cycles at a high current density of 2 A g^(-1)).The optimized sodiumion full cell with FeSe_(2)@CoSe_(2)/FeSe_(2)as the anode and Na 3 V 2(PO 4)3 as the cathode still demonstrates excellent ***,a ca-pacity of 272 mAh g^(-1)(at 1 A g^(-1))within the operating voltage from 1 to 3.8 V can be *** work illustrates the potential of bimetallic selenides with heterostructures for performance enhancement of sodium-ion batteries.

关键词： Cobalt-iron selenide Heterojunctions Sodium storage Anode material Full battery

In-situ formation of nitrogen doped microporous carbon nanospheres derived from polystyrene as lubricant additives for anti-wear and friction reduction

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Friction 2024年第3期12卷 439-451页

作者： Yixin WANG Qi LU Huijie xie Shujuan LIU qian YE Feng ZHOU Weimin LIU State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

This study presents a nitrogen-doped microporous carbon nanospheres(N@MCNs)prepared by a facile polymerization–carbonization process using low-cost *** N element in situ introduces polystyrene(PS)nanospheres via emulsion polymerization of styrene with cyanuric chloride as crosslinking agent,and then carbonization obtains N@*** as-prepared carbon nanospheres possess the complete spherical structure and adjustable nitrogen amount by controlling the relative proportion of tetrachloromethane and cyanuric *** friction performance of N@MCNs as lubricating oil additives was surveyed utilizing the friction experiment of ball-disc *** results showed that N@MCNs exhibit superb reduction performance of friction and *** the addition of N@MCNs was 0.06 wt%,the friction coefficient of PAO-10 decreased from 0.188 to 0.105,and the wear volume reduced by 94.4%.The width and depth of wear marks of N@MCNs decreased by 49.2% and 94.5%,*** carrying capacity of load was rocketed from 100 to 400 N *** the analysis of the lubrication mechanism,the result manifested that the prepared N@MCNs enter clearance of the friction pair,transform the sliding friction into the mixed friction of sliding and rolling,and repair the contact surface through the repair ***,the tribochemical reaction between nanoparticles and friction pairs forms a protective film containing nitride and metal oxides,which can avert direct contact with the matrix and improve the tribological *** experiment showed that nitrogen-doped polystyrene-based carbon nanospheres prepared by in-situ doping are the promising materials for wear resistance and reducing *** preparing method can be ulteriorly expanded to multi-element co-permeable *** and boron co-doped carbon nanospheres(B,N@MCNs)were prepared by mixed carbonization of N-enriched PS and boric acid,and exhibited high load carrying capacity and good tribolog

关键词： lubricant additives hypercrosslinked polystyrene carbon nanospheres friction reduction anti-wear

A frequency servo SoC with output power stabilization loop technology for miniaturized atomic clocks

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Journal of Semiconductors 2024年第6期45卷 13-22页

作者： Hongyang Zhang Xinlin Geng Zonglin Ye Kailei Wang qian xie Zheng Wang School of Integrated Circuit Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic *** proposed power stabilization loop(PSL)technique,incorporating an off-chip power detector(PD),ensures that the output power of the FS-SoC remains stable,mitigating the impact of power fluctuations on the atomic clock's ***,a one-pulse-per-second(1PPS)is employed to syn-chronize the clock with *** using 65 nm CMOS technology,the measured phase noise of the FS-SoC stands at-69.5 dBc/Hz@100 Hz offset and-83.9 dBc/Hz@1 kHz offset,accompanied by a power dissipation of 19.7 *** Cs atomic clock employing the proposed FS-SoC and PSL obtains an Allan deviation of 1.7×10^(-11) with 1-s averaging time.

关键词： CMOS technology atomic clock phase-locked loop output power stabilization 1PPS

Refined acoustic holography via nonlocal metasurfaces

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 113-123页

作者： Shuhuan xie Hongyu Ma Junmei Cao Fangshuo Mo qian Cheng Yong Li Tong Hao Institute of Acoustics School of Physics Science and EngineeringTongji UniversityShanghai 200092China Center for Spatial Information Science and Sustainable Development Applications Tongji UniversityShanghai 200092China College of Surveying and Geo-Informatics Tongji UniversityShanghai 200092China

Holography can provide the desired wavefront phase and/or amplitude for imaging,particle manipulation,bacteria trapping,and cell patterning in optics and ***,previous work on acoustic holography is mostly based on local design optimization,either using active control of the sound source or relying on the structural design to provide the desired *** precise control over the acoustic field remains a significant ***,we realize refined single-plane symmetric binary amplitude,asymmetric intensity gradient amplitude,and bi-objective hologram through the non-local holographic imaging theory that considers the acoustic coupling of structural units in *** taking into account the self-radiation and mutual radiation between many small units on a plate of well-designed thickness,as well as the transmission through the plate's apertures,we can effectively regulate the sound field behind the *** demonstrate the effectiveness of our approach through numerical simulations and experiments,showcasing a circle,a black hole,and a bi-objective with a circle and a square ***,the acoustic black hole hologram precisely reconstructs the intensity gradient distribution at two bright *** non-local holographic imaging theory is valuable for the fine-intensity regulation of the sound field and is expected to be applied in ultrasound diagnosis and treatment,medical imaging,and other fields.

关键词： acoustic holograms non-local interactions fine intensity modulation acoustic metasurfaces

Optical modification of nonlinear crystals for quasi-parametric chirped-pulse amplification

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Fundamental Research 2024年第1期4卷 43-50页

作者： qian Lin Jingui Ma Zhe Yin Peng Yuan Jing Wang Guoqiang xie Liejia qian Key Laboratory for Laser Plasmas(MOE) Collaborative Innovation Center of IFSASchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

Quasi-parametric chirped-pulse amplification(QPCPA),which features a theoretical peak power much higher than those obtained with Ti:sapphire laser or optical parametric chirped-pulse amplification,is promising for future ultra-intense *** doped rare-earth ion used for idler dissipation is critical for effective QPCPA,but is usually not compatible with traditional *** far,only one dissipative crystal of Sm^(3+)-doped yttrium calcium oxyborate has been grown and *** we introduce optical means to modify traditional crystals for QPCPA *** theoretically demonstrate two dissipation schemes by idler frequency doubling and sum-frequency generation with an additional *** contrast to absorption dissipation,the proposed nonlinear dissipations ensure not only high signal efficiency but also high small-signal *** demonstrated ability to optically modify crystals will facilitate the wide application of QPCPA.

关键词： Quasi-parametric amplifier Second-harmonic generation Sum-frequency generation Back conversion Idler dissipation