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Tungsten 2024年第03期6卷 621-632页

作者： jing Zhao Lei Gao Jian-Jun Zhao wei wei Hui-Qin Yun Ru Xing huai-jin Ma Xiang jin Luo-Meng Chao School of Physical Science and Technology Key Laboratory of Magnetism and Magnetic Materials for Higher Education in Inner Mongolia Autonomous Region Baotou Teachers' College National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths School of Physics and Electronic Information Inner Mongolia Normal University College of Science Inner Mongolia University of Science and Technology

In this study,a novel method is proposed for producing perovskite rare-earth manganese oxide magnetic refrigeration materials that exhibit superior properties compared to similar *** maximum magnetic entropy change values for this sample are 1.44 and 3.75 J·kg-1·K-1for magnetic fields of 2 and 7 T,***,its relative cooling power has been calculated to be 101.96 and 404.78 J·kg-1,indicating good *** results were obtained using the sample synthesized under a pressure of 4 GPa,and the sample has undergone a second phase *** critical behavior of the sample fits well with the mean field *** different magnetic fields,there is a significant overlap between the values of the maximum magnetic entropy change and the temperature-averaged entropy change,indicating that the refrigeration performance of the sample after high pressure can approach its maximum capability.

关键词： High-pressure synthesis Magnetocaloric effect Relative cooling power Magnetic phase transition

Flavidanolides A and B from Isodon flavidus

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中国化学快报:英文版 2023年第9期34卷 160-164页

作者： Jiang-Hai Ye Guo-Yong Luo Chen-Liang Zhao Zheng-Ming Liang jin-huai wei Ya-Hua Liu Kang He Lu-Tai Pan jing-Jie Zhang Juan Zou Hong-Jie Zhang School of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China School of Chinese Medicine Hong Kong Baptist UniversityHong Kong SAR 999077China

A phytochemical investigation on Isodon flavidus led to the isolation of flavidanolide A(1),a rearranged diterpenoid featuring a six/seven/five-membered tricyclic skeleton,together with flavidanolide B(2),an uncommon heterodimeric diterpenoid consisting of a norabietane and a seco-isopimarane monomeric *** structures were elucidated by extensive spectroscopic data and single-crystal X-ray diffraction *** plausible biosynthetic routes were also *** the bioassay,flavidanolide B was found to exhibit good inhibitory effect against lipopolysaccharide(LPS)-induced nitric oxide(NO)production in RAW264.7 cells comparable to positive control pyrrolidinedithiocarbamate ammonium(PDTC),which provided evidence for the medicinal value of *** as a folk medicine for treating inflammatory diseases.

关键词： Isodon flavidus Rearranged six/seven/five-membered skeleton Heterodimeric diterpenoid Plausible biosynthetic pathway Antiinflammatory effects

Geological reservoir and resource potential(10^(13)m^(3))of gas hydrates in the South China Sea

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China Geology 2024年第3期7卷 422-444页

作者： Pi-bo Su wei wei Yun-bao Sun Yao-yao Lü huai Cheng wei-feng Han wei Zhang jin-qiang Liang National Engineering Research Center for Gas Hydrate Exploration and Development Guangzhou 511458China Sanya Institute of South China Sea Geology Guangzhou Marine Geological SurveySanya 572025China Central Laboratory of Geological Sciences Research Institute of Petroleum Exploration and DevelopmentLangfang 065007China Qingdao Institute of Marine Geology Qingdao 266237China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China

A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are *** this study,this study analyzed the applicability of resource evaluation methods,including the volumetric,genesis,and analogy methods,and estimated NGHs resource potential in the South China Sea by using scientific resource evaluation methods based on the factors controlling the geological accumulation and the reservoir characteristics of ***,this study compared the evaluation results of NGHs resource evaluations in representative worldwise sea areas via rational *** results of this study are as follows:(1)The gas hydrate accumulation in the South China Sea is characterized by multiple sources of gas supply,multi-channel migration,and extensive accumulation,which are significantly different from those of oil and gas and other unconventional resources.(2)The evaluation of gas hydrate resources in the South China Sea is a highly targeted,stratified,and multidisciplinary evaluation of geological resources under the framework of a multi-type gas hydrate resource evaluation system and focuses on the comprehensive utilization of multi-source heterogeneous data.(3)Global NGHs resources is n×10^(15)m^(3),while the NGHs resources in the South China Sea are estimated to be 10^(13)m^(3),which is comparable to the abundance of typical marine NGHs deposits in other parts of the *** the South China Sea,the NGHs resources have a broad prospect and provide a substantial resource base for production tests and industrialization of NGHs.

关键词： Reservoir characteristics Natural gas hydrates Gas migration Resource potential Resource evaluation methods Hierarchical evaluation system Volumetric method South China Sea Clean energy exploration engineering

A Comprehensive Review of Thermal Performance Improvement of High-Temperature Heat Pipes

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Journal of Thermal Science 2024年第2期33卷 625-647页

作者： CHEN Qihan ZHOU jingzhi ZHOU Guohui CHENG Keyong huai Xiulan wei Gaosheng School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing100096China Nanjing Institute of Future Energy System Nanjing211135China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China

Energy efficiency issues are being focused on the growing concern of global warming and environmental *** high-temperature heat pipe(HTHP) is an effective and environmental-friendly heat transfer device employed in many industries,including solar power generation,high-temperature flue gas waste heat recovery,industrial furnaces,nuclear industries,and *** a critical factor in HTHPs,thermal performance is mainly introduced in the entire *** date,most reviews have been published concerning one or several application ***,to the best of authors' knowledge,it is hard to find a review discussing how to improve the thermal performance of HTHPs ***,the impact on the performance of three main components of HTHPs over the past 30 years is introduced:the working fluid,the HTHP structure,and the wick ***,it is a considerable review of the optimal operating conditions for each direction,and we expect this paper contribute to improving the thermal performance of ***,current numerical simulations and theoretical research on the heat transfer limit of HTHPs are *** significant hypotheses used in numerical simulations and the present theoretical studies are compiled ***,some potential future directions and tentative suggestions for HTHP research are put forward.

关键词： high-temperature heat pipe review alkali metal heat pipe thermal performance

Theoretical understanding of correlation between magnetic phase transition and the superconducting dome in high-Tc cuprates

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 167-173页

作者： Chen Zhang Cai-Xin Zhang Su-huai wei Haiqing Lin Hui-Xiong Deng State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Computational Science Research Center Beijing 100193China

Many issues concerning the origin of high-temperature superconductivity(HTS)are still under *** example,how the magnetic order varies with doping and its relationship with the superconducting temperature(Tc);and why Tcalways peaks near the quantum critical *** this paper,taking hole-doped La_(2)CuO_(4)as a classical example,we employ the first-principles band structure and total energy calculations with Monte Carlo simulations to explore how the symmetry-breaking magnetic ground state evolves with hole doping and the origin of a dome-shaped superconductivity region in the phase *** demonstrate that the local antiferromagnetic order and doping play key roles in determining the electron-phonon coupling,thus ***,the La_(2)CuO_(4)possesses a checkerboard local antiferromagnetic ground *** the hole doping increases,Tcincreases with the enhanced electron-phonon coupling *** as the doping increases further,the strength of the antiferromagnetic interaction weakens and spin fluctuation *** the critical doping level,a magnetic phase transition occurs that reduces the local antiferromagnetism-assisted electron-phonon coupling,thus diminishing the *** superconductivity disappears in the heavily overdoped region when the ferromagnetic order *** observations could account for why cuprates have a dome-shaped superconductivity region in the phase *** study,thus,contributes to a fundamental understanding of the correlation between doping,local magnetic order,and superconductivity of HTS.

关键词： high-temperature superconductivity antiferromagnetic order electron-phonon coupling doping effect cuprates

Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei

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Journal of Forestry Research 2024年第1期35卷 12-28页

作者： Shicheng Su Nianqing jin Xiaoli wei College of Forestry Guizhou UniversityGuiyang 550025People’s Republic of China Institute for Forest Resources and Environment of Guizhou Guizhou UniversityGuiyang 550025People’s Republic of China

Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the *** this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei *** canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following *** improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light *** the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral *** photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light *** a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal *** a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of *** seedlings,and a reduction increased light absorption and use capacity and height:diameter *** growth advantage transformed from diameter to height,enabling seedlings to access more *** findings suggest that the regeneration of shade-tolerant species such as *** could be enhanced if a targeted approach to thinning based on stand type was adopted.

关键词： Thinning Understory light environment Phoebe bournei Photosynthetic performance Growth performance

Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient

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Chinese Journal of Chemical Engineering 2024年第5期69卷 212-219页

作者： Guangxia jin Yuxue Wu Feng wei School of Biological and Chemical Engineering NingboTech UniversityNingbo 315100China

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar *** study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive *** introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream ***,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation ***,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for *** using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

关键词： Solvent gradient Twin-column recycling chromatography Purification Minor component Natural products

Pain perception enhancement in consecutive secondeye phacoemulsification cataract surgeries under topical anesthesia

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1510-1518页

作者： Jia-wei Luo Yan-Hua Chen Jian-Feng Yu Yi-Xun Chen Min Ji huai-jin Guan Eye Institute Affiliated Hospital of Nantong UniversityMedical School of Nantong UniversityNantong 226001Jiangsu ProvinceChina Nantong Center for Disease Control and Prevention Nantong 226001Jiangsu ProvinceChina

Cataract is the main cause of visual impairment and blindness worldwide while the only effective cure for cataract is still *** phacoemulsification under topical anesthesia has been the routine procedure for cataract ***,patients often grumbled that they felt more painful during the second-eye surgery compared to the first-eye *** intraoperative pain experience has negative influence on satisfaction and willingness for second-eye cataract surgery of patients with bilateral *** ocular pain is a complicated process induced by the nociceptors activation in the peripheral nervous ***,neuropsychological,and pharmacological factors work together in the enhancement of intraoperative *** published literatures have focused on the pain enhancement during the secondeye phacoemulsification *** this review,we searched PubMed database for articles associated with pain perception differences between consecutive cataract surgeries published up to Feb.1,*** summarized the recent research progress in mechanisms and interventions for pain perception enhancement in consecutive secondeye phacoemulsification cataract *** review aimed to provide novel insights into strategies for improving patients’intraoperative experience in second-eye cataract surgeries.

关键词： ocular pain cataract surgery topical anesthesia intraoperative experience second-eye phacoemulsification

MD Simulation of Diffusion Behaviors in Collision Welding Processes of Al-Cu, Al-Al, Cu-Cu

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Computers, Materials & Continua 2024年第6期79卷 3455-3468页

作者： Dingyi jin Guo wei School of Intelligent Manufacturing Hunan First Normal UniversityChangsha410082China School of Physics and Technology Center for Ion Beam ApplicationHubei Nuclear Solid Physics Key LaboratoryWuhan UniversityWuhan430072China

To investigate the effects of material combinations and velocity conditions on atomic diffusion behavior near collision interfaces,this study simulates the atomic diffusion behavior near collision interfaces in Cu-Al,Al-Al and Cu-Cu combinations fabricated through collision welding using molecular dynamic(MD)*** atomic diffusion behaviors are compared between similar metal combinations(Al-Al,Cu-Cu)and dissimilar metal combinations(Al-Cu).By combining the simulation results and classical diffusion theory,the diffusion coefficients for similar and dissimilar metal material combinations under different velocity conditions are *** effects of material combinations and collision velocity on diffusion behaviors are also *** diffusion behaviors of dissimilar material combinations strongly depend on the transverse velocity,whereas those of the similar material combinations are more dependent on the longitudinal *** findings can provide guidance for optimizing welding parameters.

关键词： Atomic diffusion behavior molecular dynamics collision welding

Revolutionizing plasmonic platform via magnetic field-assisted confined ultrafast laser deposition of high-density,uniform,and ultrafine nanoparticle arrays

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International Journal of Extreme Manufacturing 2024年第3期6卷 428-438页

作者： jin Xu Lingfeng Wang Peilin Yang Haoqing Jiang huai Zheng Licong An Xingtao Liu Gary J Cheng School of Industrial Engineering Purdue UniversityWest LafayetteIN 47906United States of America Institute of Technological Sciences Wuhan UniversityWuhanHubei 430072People’s Republic of China

The remarkable capabilities of 2D plasmonic surfaces in controlling optical waves havegarnered significant ***,the challenge of large-scale manufacturing of uniform,well-aligned,and tunable plasmonic surfaces has hindered their *** address this,we present a groundbreaking tunable plasmonic platform design achieved throughmagnetic field(MF)assisted ultrafast laser direct deposition in *** precise control of metal nanoparticles(NPs),with cobalt(Co)serving as the model material,employing an MF,and fine-tuning ultrafast laser parameters,we have effectively converted coarse and non-uniform NPs into densely packed,uniform,and ultrafine NPs(~3 nm).This revolutionary advancement results in the creation of customizable plasmonic‘hot spots,’which play a pivotal role insurface-enhanced Raman spectroscopy(SERS)*** profound impact of this designable plasmonic platform lies in its close association with plasmonic resonance and *** the plasmonic nanostructures resonate with incident light,they generate intense local electromagnetic fields,thus vastly increasing the Raman scattering *** enhancement leads to an outstanding 2–18 fold boost in SERS performance and unparalleled sensing sensitivity down to 10^(-10)***,the plasmonic platform also demonstratesrobustness,retaining its sensing capability even after undergoing 50 cycles of rinsing andre-loading of ***,this work adheres to green manufacturing standards,making it an efficient and environmentally friendly method for customizing plasmonic‘hot spots’inSERS *** study not only achieves the formation of high-density,uniform,and ultrafine NP arrays on a tunable plasmonic platform but also showcases the profound relation betweenplasmonic resonance and energy *** outstanding results observed in SERS sensors further emphasize the immense potential of this technology for energy-relatedapplications,including photocatalysis,ph

关键词： magnetic field manipulation laser deposition metasurface SERS