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Doping engineering of iron oxide nanoparticles towards high performance and biocompatible T_(1)-weighted MRI contrast agents

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Rare Metals 2024年第1期43卷 298-308页

作者： Xue Xu Ping-Li Dong Yu-Yun Chai Run Yang Zhen-Hui Ma chi-chong lu Department of Chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China Department of Physics Beijing Technology and Business UniversityBeijing 100048China

Extremely small-sized iron oxide nanoparticles(IONPs) are of great interest in magnetic resonance imaging(MRI) due to their biosafety as an alternative to clinical gadolinium(Ⅲ) complexes-based contrast *** when the particle size is less than 10 nm,it has strong diffusion ability and deep penetration distance in tumor *** doping can significantly enhance the T_(1)contrast effect of nanoparticles by regulating the surface exposed ***,the nucleation and growth processes of multi-component synthesis systems are complex and difficult to be accurately controlled,leading to great challenges in the synthesis of ultra-small-sized nanoparticles with different components and ***,extremely smallsized superparamagnetic gadolinium-doped iron oxide nanoparticles(GdIONPs,Gd_(x)Fe_(3-x)O_(4) NPs) with adjustable doping amount and controllable size in the range of 3.5-7.5 nm were synthesized by thermal ***,as-synthesized GdIONPs were surface modified with a highly water-soluble and biocompatible carboxyl-polyethylene glycol-phosphoric acid ligand with high binding ***_(0.65)Fe_(2.35)O_(4) NPs exhibited very high r_(1) relaxivity of 10.6 mmol^(-1)·L·s^(-1) in terms of all metal concentrations and 49.0 mmol^(-1)·L·s^(-1) in terms of gadolinium alone,respectively,3 and 14 times higher than clinical T_(1) contrast agents(Gd-DTPA).GdIONPs can continuously obtain high resolution images of blood vessels,and can be used as an efficient and multifunctional contrast agent for MR T_(1)*** stable and efficient doping strategy provides an easy and effective method to individually optimize the magnetic properties of complex oxides and their relaxation effects for a variety of biomedical applications.

关键词： Iron oxide nanoparticles Small size Magnetic resonance imaging Substitutional doping Gd dopant

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Cell-free biocatalysis coupled with photo-catalysis and electro-catalysis: Efficient CO2-to-chemical conversion

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Green Energy & Environment 2024年第9期9卷 1366-1383页

作者： Junzhu Yang chi-Kit Sou Yuan lu Key Laboratory of Industrial Biocatalysis Ministry of Education Tsinghua University Department of Chemical Engineering Tsinghua University

The increasing atmospheric carbon dioxide （CO2） concentration has exposed a series of crises in the earth's ecological *** to effectively fix and convert carbon dioxide into products with added value has attracted the attention of many ***-free enzyme catalytic system coupled with electrical and light have been a promising attempt in the field of biological carbon fixation in recent *** this review,the research progresses of photoenzyme catalysis,electroenzyme catalysis and photo-electroenzyme catalysis for converting carbon dioxide into chemical products in cell-free systems are systematically *** focus on reviewing and comparing various coupling methods and principles of photoenzyme catalysis and electroenzyme catalysis in cell-free systems,especially the materials used in the construction of the coupling system,and analyze and point out the characteristics and possible problems of different coupling ***,we discuss the major challenges and prospects of coupling physical signals and cell-free enzymatic catalytic systems in the field of CO2fixation,suggesting possible strategies to improve the carbon sequestration capacity of such systems.

关键词： CO 2 fixation Cell-free system Enzyme Photoenzyme catalysis Electroenzyme catalysis

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Capturing and visualizing the phase transition mediated thermal stress of thermal barrier coating materials via a cross-scale integrated computational approach

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Journal of Advanced Ceramics 2024年第4期13卷 413-428页

作者： Mengdi Gan Tianlong lu Wei Yu Jing Feng Xiaoyu chong Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The generation and evaluation of severely high thermal stress(σ)is known to be responsible for failure of thermal barrier coatings(TBCs)during thermal *** is crucial and challenging to capture fluctuations inσcaused by the phase transition,which has motivated us to develop a high-throughput multiscale evaluation method forσin TBCs that considers the phase transition of the top ceramic materials by coupling first-principles calculations with finite element *** method quantitatively evaluates and visualizesσof the real TBC structure under thermal cycling by multifield ***,the thermophysical properties calculated by the first-principles calculations consider the effects of temperature and phase transition,which not only reduces the cost of obtaining data but also has a more physical *** this work,rare earth tantalites(RETaO_(4))are introduced as ceramic layers,and the results demonstrate thatσundergoes a rapid escalation near the phase transition temperature(T_(t)),particularly in the TBCs_GdTaO_(4) system,where it rises from 224 to 435 *** discontinuity inσmay originate from the significant alterations in Young’s modulus(increase by 27%–78%)and thermal conductivity(increase by 53%–146%)near T_(t).The TBCs_NdTaO_(4) and TBCs_SmTaO_(4) systems exhibit noteworthy temperature drop gradients and minimalσfluctuations,which are beneficial for extending service lifetime of *** approach facilitates the prediction of failure mechanisms and provides theoretical guidance for the reverse design of TBC materials to obtain low thermal stress systems.

关键词： thermal conductivity first-principles calculations thermodynamics thermal stress thermophysical properties

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Analgesic and anti-inflammatory activity of Cotinus coggygria *** in vivo

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Asian Pacific Journal of Tropical Biomedicine 2024年第6期14卷 225-235页

作者： Kai lu chong-Yu Yang Zhao-Hong Yan Department of Anesthesiology Qiantang Campus Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou310018China Department of Anesthesiology 3201 HospitalHanzhong723000China Department of Anesthesiology The Second Affiliated Hospital of the Chinese People’s Liberation Army Air Force Medical UniversityXi’an710038China

Objective:To assess the analgesic and anti-inflammatory effects of standardized extract of Cotinus coggygria(***)in different animal ***:*** extracts(25,50,and 100 mg/kg)were administered to rats and mice(n=6)during hot plate,tail-flick,acetic acid-induced writhing,and formalin tests to determine its analgesic *** anti-inflammatory activity of *** extracts was evaluated by histamine and carrageenan-induced paw edema,cotton pellet-induced granuloma,and acetic acid-induced peritoneal capillary dye leakage ***:*** extracts(50 and 100 mg/kg)significantly alleviated thermal and chemical-induced pain in rodents(P<0.05).It also demonstrated notable anti-inflammatory properties by mitigating histamine and carrageenan-induced paw edema,granuloma deposits,and vascular permeability(P<0.05).Moreover,*** extracts remarkably reduced TNF-α,IL-1β,IL-6,COX-2,and oxidative stress in rat paws(P<0.05).Carrageenan-induced histological aberrations in hind paw tissues were effectively(P<0.05)mitigated by treatment with *** ***:*** *** show analgesic and anti-inflammatory effects via inhibition of COX-2 and inflammatory and oxidative mediators.

关键词： Antioxidant Carrageenan Cotinus coggygria Scop. Anti-inflammatory Analgesic Pain TNF-α Fustin

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Numerical and experimental study on the falling film flow characteristics with the effect of co-current gas flow in hydrogen liquefaction process

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Petroleum Science 2024年第2期21卷 1369-1384页

作者： chong-Zheng Sun Yu-Xing Li Hui Han Xiao-Yi Geng Xiao lu College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266590ShandongChina College of Pipeline and Civil Engineering/Shandong Provincial Key Laboratory of Oil&Gas Storage and Transportation Safety China University of PetroleumQingdao 266580ShandongChina

Liquid hydrogen storage and transportation is an effective method for large-scale transportation and utilization of hydrogen energy. Revealing the flow mechanism of cryogenic working fluid is the key to optimize heat exchanger structure and hydrogen liquefaction process(LH2). The methods of cryogenic visualization experiment, theoretical analysis and numerical simulation are conducted to study the falling film flow characteristics with the effect of co-current gas flow in LH2spiral wound heat *** results show that the flow rate of mixed refrigerant has a great influence on liquid film spreading process, falling film flow pattern and heat transfer performance. The liquid film of LH2mixed refrigerant with column flow pattern can not uniformly and completely cover the tube wall surface. As liquid flow rate increases, the falling film flow pattern evolves into sheet-column flow and sheet flow, and liquid film completely covers the surface of tube wall. With the increase of shear effect of gas-phase mixed refrigerant in the same direction, the liquid film gradually becomes unstable, and the flow pattern eventually evolves into a mist flow.

关键词： Hydrogen liquefaction Spiral wound heat exchanger Flow pattern transition Falling film flow

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Boosting Hydrogen Storage Performance of MgH_(2) by Oxygen Vacancy-Rich H-V_(2)O_(5) Nanosheet as an Excited H-Pump

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Nano-Micro Letters 2024年第8期16卷 398-416页

作者： Li Ren Yinghui Li Zi Li Xi Lin chong lu Wenjiang Ding Jianxin Zou National Engineering Research Center of Light Alloys Net Forming&State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Shanghai Engineering Research Center of Mg Materials and Applications&School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Center of Hydrogen Science Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Instrumental Analysis Center of SJTU Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

MgH_(2) is a promising high-capacity solid-state hydrogen storage material,while its application is greatly hindered by the high desorption temperature and sluggish ***,intertwined 2D oxygen vacancy-rich V_(2)O_(5) nanosheets(H-V_(2)O_(5))are specifically designed and used as catalysts to improve the hydrogen storage properties of MgH_(2).The as-prepared MgH_(2)-H-V_(2)O_(5) composites exhibit low desorption temperatures(Tonset=185℃)with a hydrogen capacity of 6.54 wt%,fast kinetics(Ea=84.55±1.37 kJ mol^(-1) H_(2) for desorption),and long cycling ***,hydrogen absorption can be achieved at a temperature as low as 30℃ with a capacity of 2.38 wt%within 60 ***,the composites maintain a capacity retention rate of~99%after 100 cycles at 275℃.Experimental studies and theoretical calculations demonstrate that the in-situ formed VH_(2)/V catalysts,unique 2D structure of H-V_(2)O_(5) nanosheets,and abundant oxygen vacancies positively contribute to the improved hydrogen sorption ***,the existence of oxygen vacancies plays a double role,which could not only directly accelerate the hydrogen ab/de-sorption rate of MgH_(2),but also indirectly affect the activity of the catalytic phase VH_(2)/V,thereby further boosting the hydrogen storage performance of MgH_(2).This work highlights an oxygen vacancy excited“hydrogen pump”effect of VH_(2)/V on the hydrogen sorption of Mg/MgH_(2).The strategy developed here may pave a new way toward the development of oxygen vacancy-rich transition metal oxides catalyzed hydride systems.

关键词： Hydrogen storage MgH_(2) V_(2)O_(5)nanosheets Oxygen vacancies VH_(2)

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Piperine regulates the circadian rhythms of hepatic clock gene expressions and gut microbiota in high-fat diet-induced obese rats

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Food Science and Human Wellness 2024年第3期13卷 1617-1627页

作者： Weiyun Zhang chi-Tang Ho Wenlian Wei Jie Xiao Muwen lu Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods College of Food ScienceSouth China Agricultural UniversityGuangzhou 510642China Department of Food Science Rutgers UniversityNew Brunswick 08901USA

The interplay between the host circadian clock and microbiota has significant influences on host metabolism processes,and circadian desynchrony triggered by high-fat diet(HFD)is closely related to metabolic *** this study,the modulatory effects of piperine(PIP)on lipid metabolism homeostasis,gut microbiota community and circadian rhythm of hepatic clock gene expressions in obese rats were *** Sprague-Dawley(SD)rats were fed with normal diet(ND),HFD and HFD supplemented with PIP,*** 9 weeks,rats were sacrificed with tissue and fecal samples collected for circadian *** showed that chronic PIP administration ameliorated the obesity-induced alterations in lipid metabolism and dysregulation of hepatic clock gene expressions in obese *** gut microbial communities studied through 16S rRNA sequencing showed that PIP ameliorated the imbalanced nicrobiota and recovered the circadian rhythm of Lactobacillaceae,Desulfovibrionaceae,Paraprevotellaceae,and *** fecal metabolic profiles indicated that 3-dehydroshikimate,cytidine and lithocholyltaurine were altered,which were involved in the amino acid and fatty acid metabolism *** findings could provide theoretical basis for PIP to work as functional food to alleviate the lipid metabolism disorder,circadian rhythm misalignment,and gut microbiota dysbiosis with wide applications in the food and pharmaceutic industries.

关键词： Piperine Circadian clock Obesity Gut microbiota

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Room-temperature nitrogen-rich niobium nitride photodetector for terahertz detection

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Optoelectronics Letters 2024年第11期20卷 641-646页

作者： lu Xuehui LIU Binding chi Chengzhu LIU Feng SHI Wangzhou Department of Physics Mathematics & Science College Shanghai Normal University

A sensitive room-temperature metal-semiconductor-metal(MSM) structure is fabricated on high-resistivity silicon substrates(ρ>4 000 Ω·cm) for terahertz(THz) detection by utilizing the photoconductive effect.

关键词： A

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Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath

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Earth and Planetary Physics 2024年第1期8卷 47-58页

作者： Jin Guo TianRan Sun San lu QuanMing lu Yu Lin XueYi Wang chi Wang RongSheng Wang Kai Huang School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology/CAS Key Lab of Geospace Environment University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Space Science Center Chinese Academy of SciencesBeijing 100190China Physics Department Auburn UniversityAuburnALUSA

Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the *** X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a *** performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic *** all cases,magnetic reconnection occurs at low latitude *** soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the *** X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray ***,the magnetopause boundary can be identified using multiple viewing *** also find that solar wind conditions have little effect on the magnetopause *** Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered.

关键词： magnetopause X-ray emissivity X-ray imaging SMILE global hybrid-PIC simulation

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Transient Voltage Support Strategy of Grid-forming Medium Voltage Photovoltaic Converter in the LCC-HVDC System

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 1849-1864页

作者： Hong lu Xianyong Xiao Guangfu Tang Zhiyuan He Zhiguang Lin chong Gao Zixuan Zheng College of Electrical Engineering Sichuan UniversityChengdu 610065China State Key Lab of Advance Power Transmission Technology China Electric Power Research InstituteBeijing 100192China College of Electrical Engineering Sichuan UniversityChengdu 610065China.

The participation of photovoltaic(PV)plants in supporting the transient voltage caused by commutation failure in the line-commutated-converter-based high voltage direct current(LCC-HVDC)system is of great significance,as it can enhance the DC transmission ***,it is found that the gridfollowing(GFL)PV converters face the problem of mismatch between reactive power response and transient voltage characteristic when the voltage converts from low voltage to overvoltage,further aggravating the overvoltage ***,this article proposes a transient voltage support strategy based on the gridforming(GFM)medium voltage PV *** proposed strategy takes the advantage of the close equivalent electrical distance between the converter and grid,which can autonomously control the converter terminal voltage through GFM control with adaptive voltage droop *** simulation results show that the proposed strategy can ensure the output reactive power of the PV converter quickly matches the transient voltage characteristic at different stages,indicating that the proposed strategy can effectively support the transient voltage.

关键词： Commutation failure grid-forming(GFM) photovoltaic(PV)converter reactive power response transient voltage

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