检索结果-南通市图书馆

Effect of rare earth on primary carbides in H13 die steel and their addition method:a review

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第3期31卷 531-551页

作者： jing-feng wang Lin-zhu wang Chao-yi chen Xiang wang Fei Zhao School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina Zhengzhou Railway Vocational and Technical College Zhengzhou 450000HenanChina Guizhou Provincial University Key Laboratory of High Performance Battery Materials Guizhou UniversityGuiyang 550025GuizhouChina Shougang Guiyang Special Steel Co. Guiyang 550005GuizhouChina

Larger-sized primary carbides lead to stress concentration during the application of H13 hot-work die steel,resulting in microcracks and fatigue *** earth was usually added to modify the carbides and *** existing literature is reviewed on the effect of rare earth on primary carbides in H13 steel.A comprehensive review on the effect of rare earth on the characteristics of primary carbides,i.e.,number,size,morphology,and thermal stability in H13 steel,was *** precipitation mechanism and nucleation of primary carbides with rare earth were *** position and form of rare earth in steel and their effects on alloying elements segregation were *** addition techniques of rare earth in H13 steel were compared,and the prospects for other uncommon rare earth and emerging technology were *** on the current references,it can be known that adding rare earth facilitated refined and dispersed primary *** size of primary carbides would be reduced,and their morphology would be improved because the rare earth inclusions formed in H13 steel can act as nucleation cores forγ-Fe orδ-Fe,refining the dendritic ***,the number of primary carbides at grain boundaries would be significantly ***,rare earth had little impact on thermal *** nucleation of primary carbides tended to be inhibited due to the modification of inclusions by rare earth which were likely to be nucleation cores for primary *** earth had been reported to affect the mechanism and process of primary carbide ***,the addition of rare earth can inhibit the segregation of alloying elements and carbon diffusion by ***,laboratory experiments and theoretical calcu-lations need to be conducted to study the states and evolution of rare earth steels.

关键词： Rare earth H13 die steel Primary carbide Nucleation Dendritic structure

Design of a large momentum acceptance proton therapy gantry utilizing AG-CCT magnets

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-11页

作者： Liao, yi-cheng Liu, Xu wang, Wei yang, Zi-yi chen, Qu-Shan Qin, Bin Huazhong Univ Sci & Technol State Key Lab Adv Electromagnet Technol Wuhan 430074 Peoples R China

The application of superconducting (SC) technology enables magnets to excite strong fields with small footprints, which has great potential for miniaturizing proton therapy gantries. However, the slow ramping rate of SC magnets results in a low treatment efficiency compared with normal-conducting (NC) gantries. To address this problem, this study proposes a compact proton therapy gantry design with a large momentum acceptance utilizing alternating-gradient canted-cosine-theta (AG-CCT) SC magnets. In our design, a high-transmission degrader is mounted in the middle of the gantry, and the upstream beamline employs NC magnets with small apertures. Downstream of the degrader, large-bore AG-CCT magnets with strong alternating focusing gradients are set symmetrically as a local achromat, which realizes a momentum acceptance of 20% (or 40% in the energy domain). Therefore, only three magnetic working points are required to cover a treatment energy of 70-230 MeV. Owing to the large momentum acceptance, the proton beam after the degrader can be directly delivered to the isocenter without truncating its energy spectrum, which can significantly increase the treatment efficiency but causes severe dispersion effects during pencil beam scanning. Therefore, a compensation method was introduced by tuning the normal and skewed quadrupoles during the scanning process. As a result, the new gantry not only presents a remarkable reduction in the size and weight of the facility but also shows good potential for fast treatment.

关键词： Alternating-gradient canted-cosine-theta magnets Large momentum acceptance gantry Pencil beam scanning Proton therapy ENERGY DEGRADER BEAM OPTICS OPTIMIZATION

Carbon cathode with heteroatom doping and ultrahigh surface area enabling enhanced capacitive behavior for potassium-ion hybrid capacitors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 2136-2149页

作者： Yan Xiong Ya-Fei Zhang Chun-Liu Zhu Lei yang Huan-Yu Liang jing Shi jing-Wei chen Wei-QianTian Shuai Liu Zhi Li jing-yi Wu Huan-Lei wang School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 2V4Canada

Potassium-ion hybrid capacitors(PIHCs)are widely regarded as highly promising energy storage devices,due to their exceptional energy density,impressive power density,and abundant potassium ***,restricted by the inherent capacitive storage mechanism,the carbon cathodes possess a much lower specific capacity than battery-type ***,designing high-performance carbon cathodes is extremely urgent for the development of ***,N,O codoped porous carbon(NOPC)was fabricated through the NaCl hard template method and combined KOH/melamine chemical activation technique,displaying the characteristics of abundant N/O content(4.7 at%/16.9 at%),ultrahigh specific surface area(3092 m^(2)g^(-1))and hierarchical pore *** designed NOPC cathode delivers a high specific capacity(164.4 mAh.g^(-1)at 0.05 A.g^(-1))and superior cyclability(95.1%retention ratio at 2 A·g^(-1)over 2500 cycles).Notably,the adjustable ratio of micropores to mesopores facilitates the achievement of the optimal bal-ance between capacity and rate ***,the pseudocapacitance can be further augmented through the incorporation of N/O functional *** expected,the graphite//NOPC based PIHC possesses a high energy density of 113 Wh·kg-at 747 W·kg^(-1)and excellent capacity retention of 84.4% fter 400 cycles at 1.0 A·g^(-1).This work introduces a novel strategy for designing carbon cathodes that enhances the electrochemical performance of PIHCs.

关键词： Template method N/O co-doping High specific surface area Carbon cathode Potassium-ion capacitors

Jetting of a near-wall cavitation bubble induced by another tandem bubble

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第3期36卷 444-456页

作者： Hui Han jing-zhu wang Jian-lin Huang Peng-bo Bai Yong-gang chen yi-wei wang Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China Guangdong Aerospace Research Academy Guangzhou511458China School of Future Technology University of Chinese Academy of SciencesBeijing100049China Jianghuai Advance Technology Center Hefei230088China

Double bubbles near a rigid wall surface collapse to produce a significant jet impact,with potential applications in surface cleaning and ultrasonic ***,the dynamic behaviors of near-wall bubbles remain *** this study,we investigate the jetting of a near-wall bubble induced by another tandem *** define two dimensionless standoff distances,γ_(1),γ_(2),to represent the distances from the center of the near-wall bubble to the rigid wall and the center of controlling bubble to the center of the near-wall bubble,*** observations reveal three distinct jetting regimes for the near-wall bubble:transferred jetting,double jetting,and directed *** further investigate the jetting mechanism,numerical simulations are conducted using the compressibleInterFoam solver in the open-source framework of OpenFOAM.A detailed analysis shows that the transferred jet flow is caused by the pinch-off resulting from the axial contraction velocity at the lower end of the near-wall bubble being greater than the vertical contraction velocity,leading to a maximum jet velocity of 682.58 m/*** the case of double jetting,intense stretching between the controlling bubble and the wall leads to a pinch-off and a double jetting with a maximum velocity of 1096.29 m/*** directed jet flow is caused by the downward movement of the high-pressure region generated by the premature collapse of the controlling bubble,with the maximum jet velocity reaching 444.62 m/s.

关键词： Jetting of near-wall bubble controlling bubble impact velocity

Free radicals trigger the closure of open pores in lignin-derived hard carbons toward improved sodium-storage capacity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第7期94卷 551-559页

作者： Wen-Jun Ji Zong-Lin yi Ming-Xin Song Xiao-Qian Guo yi-Lin wang yi-Xuan Mao Fang-Yuan Su jing-Peng chen Xian-Xian Wei Li-jing Xie cheng-Meng chen CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina University of Chinese Academy of Sciences Beijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Environment and Safety Taiyuan University of Science and TechnologyTaiyuan 030001ShanxiChina

The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium ***,the formation mechanism of closed pores under the influence of pore-forming agents is not well ***,an effective chemical activation followed by a high-temperature self-healing strategy is employed to generate interconnected closed pores in lignin-derived hard carbon(HCs).By systematic experimental design combined with electron paramagnetic res-onance spectroscopy,it can be found that the content of free radicals in the carbon matrix influences the closure of open pores at high *** high activation temperature(>700 C)leads to a low free radical concentration,making it difficult to achieve self-healing of open pores at high *** activation at 700°C,a balance between pore making and self-healing is achieved in the final hard carbon.A large number of free radicals triggers rapid growth and aggregation of carbon microcrys-tals,blocking pre-formed open micropores and creating additional interconnected closed pores in as-obtained hard *** a result,the optimized carbon anode(LK-700-1300)delivers a high reversible capacity of 330.8 mA h g^(-1) at 0.03 A g^(-1),which is an increase of 86 mA h g^(-1) compared to the pristine lignin-derived carbon anode(L-700-1300),and exhibits a good rate performance(202.1 mA h g^(-1) at 1 A g^(-1)).This work provides a universal and effective guidance for tuning closed pores of hard carbons from otherprecursors.

关键词： Hard carbon Chemical activation Free radical Self-healing Closed pores Sodium ion batteries

Impact of Air Pollutants on Lung Function and Inflammatory Response in Asthma in Shanghai

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2024年第8期37卷 811-822页

作者： Guifang wang Youzhi Zhang Haiyan yang yi yang Liang Dong Peng Zhang Jie Liu Xiaodong chen yi Gong Department of Respiratory and Critical Care Medicine Quzhou People's HospitalQuzhou 324000ZhejiangChina Department of Respiratory and Critical Care Medicine Huashan Hospital Affiliated to Fudan UniversityShanghai 200040China Centre of Hydrogen Science Shanghai Jiao Tong University&Key Lab of Hydrogen ScienceShanghai 200240China Department of Respiratory and Critical Care Medicine Shanghai Public Health Clinical CentreFudan UniversityShanghai 201508China

Objective Air pollution is a leading public health *** study investigated the effect of air quality and pollutants on pulmonary function and inflammation in patients with asthma in *** The study monitored 27 asthma outpatients for a year,collecting data on weather,patient self-management[daily asthma diary,peak expiratory flow(PEF)monitoring,medication usage],spirometry and serum *** explore the potential mechanisms of any effects,asthmatic mice induced by ovalbumin(OVA)were exposed to PM_(2.5).Results Statistical and correlational analyses revealed that air pollutants have both acute and chronic effects on *** exposure showed a correlation between PEF and levels of ozone(O_(3))and nitrogen dioxide(NO_(2)).Chronic exposure indicated that interleukin-5(IL-5)and interleukin-13(IL-13)levels correlated with PM_(2.5)and PM_(10)*** asthmatic mouse models,exposure to PM_(2.5)increased cytokine levels and worsened lung ***,PM_(2.5)exposure inhibited cell proliferation by blocking the NF-κB and ERK phosphorylation *** Ambient air pollutants exacerbate asthma by worsening lung function and enhancing Th2-mediated ***,PM_(2.5)significantly contributes to these adverse *** research is needed to elucidate the mechanisms by which PM_(2.5)impacts asthma.

关键词： Ambient air pollutants Acute and chronic effects on asthma PM_(2.5) OVA-induced asthmatic mice

Satellite glial cells in sensory ganglia play a wider role in chronic pain via multiple mechanisms

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第5期19卷 1056-1063页

作者： Xiaoyun Qiu Yuanzhi yang Xiaoli Da yi wang Zhong chen Cenglin Xu Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical ScienceZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina

Satellite glial cells are unique glial cells that surround the cell body of primary sensory *** increasing body of evidence suggests that in the presence of inflammation and nerve damage,a significant number of satellite glial cells become activated,thus triggering a series of functional *** suggests that satellite glial cells are closely related to the occurrence of chronic *** this review,we first summarize the morphological structure,molecular markers,and physiological functions of satellite glial ***,we clarify the multiple key roles of satellite glial cells in chronic pain,including gap junction hemichannel Cx43,membrane channel Pannexin1,K channel subunit 4.1,ATP,purinergic P2 receptors,and a series of additional factors and their receptors,including tumor necrosis factor,glutamate,endothelin,and ***,we propose that future research should focus on the specific sorting of satellite glial cells,and identify genomic differences between physiological and pathological *** review provides an important perspective for clarifying mechanisms underlying the peripheral regulation of chronic pain and will facilitate the formulation of new treatment plans for chronic pain.

关键词： chronic pain primary sensory neurons satellite glial cells sensory ganglia

Towards accurate mapping of loess waterworn gully by integrating google earth imagery and DEM using deep learning

在线全文

学校读者我要写书评

暂无评论

International Soil and Water Conservation Research 2024年第1期12卷 13-28页

作者： Rong chen yi Zhou Zetao wang ying Li Fan Li Feng yang School of Geography and Tourism Shaanxi Normal UniversityXi'an710119China National Experiment and Teaching Demonstration Center for Geography Xi'an710119China SuperMap Software Co. Ltd.Beijing100015China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China

Accurate mapping of loess waterworn gully(LWG)is essential to further study gully erosion and geomorphological evolution for the Chinese Loess Plateau(CLP).Due to the vertical joint and collapsibility of loess,LWGs have the characteristics of zigzag and unique slope abruptness under synthetic action of hydraulic force and *** forces existing LWG mapping methods to either focus on the improvement of mapping accuracy or center on the increase of mapping ***,simultaneously achieving accurate and efficient mapping of LWG is still in its infancy under complex topographic ***,we proposed a method that innovatively integrates the loess slope abruptness feature into an improved deep learning semantic segmentation framework for LWG mapping using 0.6 m Google imagery and 5 m DEM *** selected four study areas representing typical loess landforms to test the performance of our *** proposed method can achieve satisfactory mapping results,with the F1 score,mean Intersection-over-Union(mIoU),and overall accuracy of 90.5%,85.3%,and 92.3%,*** addition,the proposed model also showed significant accuracy improvement by inputting additional topographic information(especially the slope of slope).Compared with existing algorithms(Random forests,original DeepLabV3+,and Unet),the proposed approach in this study achieved a better accuracy-efficiency ***,the method can ensure high accuracy and efficiency of the LWG mapping for different loess landform types and can be extended to study various loess gully mapping and water and soil conservation.

关键词： Loess waterworn gully Topographic information Mapping Deep learning Soil erosion Loess plateau

Influence of nonalcoholic fatty liver disease on response to antiviral treatment in patients with chronic hepatitis B:A meta-analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Hepatology 2024年第3期16卷 465-476页

作者： Shi-yi Liu Dian wang jing Liu Lu-Ping yang Gong-ying chen Department of Medicine Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Medicine Hangzhou Normal UniversityHangzhou 310011Zhejiang ProvinceChina Department of Infectious and Hepatology Diseases Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310015Zhejiang ProvinceChina

BACKGROUND Although hepatitis B virus infection is the leading cause of chronic liver injury globally,nonalcoholic fatty liver disease(NAFLD)is gradually gaining attention as another major chronic liver *** number of patients having chronic hepatitis B(CHB)with concomitant hepatic steatosis has *** To analyze the effect of NAFLD on the response to antiviral treatment in patients with *** Relevant English studies were systematically searched across PubMed,EMBASE,Web of Science,and Cochrane Library until October *** in which the treatment outcomes were compared between patients with CHB only and those with CHB and hepatic steatosis were *** Of the 2502 retrieved studies,11 articles were finally *** response until 48 wk(OR=0.87,95%CI:0.50–1.53,P=0.000)and 96 wk(OR=0.35,95%CI:0.24–0.53,P=0.24)and virological response until 96 wk(OR=0.80,95%CI:0.43–1.49,P=0.097)were lower in patients with hepatic steatosis than in patients with CHB *** Hepatic steatosis lowers the biochemical response to antiviral treatment in patients with CHB.

关键词： Nonalcoholic fatty liver disease Hepatitis B virus Antiviral treatment effect Meta-analysis