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锕系元素化学及教学建议

化学教育（中英文） 2024年第4期45卷 1-9页

作者：徐玲刘冰焦宝娟翟全国焦桓高胜利陕西师范大学化学化工学院陕西西安710062 陕西科技大学化学与化工学院陕西西安710021 西安文理学院化学工程学院陕西西安710065

依据文献和最新研究进展,从锕系元素特殊电子结构出发,着重于从锕系理论、非正常氧化态、单质的特性、水溶液中的重要反应、元素分离和应用等方面论述了锕系元素与镧系元素的差异,认识锕系元素化学,并给出教学建议。

关键词：锕系元素电子结构单质特性重要反应元素分离应用

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碱金属氧化物

化学教育（中英文） 2024年第10期45卷 10-17页

作者：李淑妮翟全国顾泉王志强雷青娟胡满成高胜利陕西师范大学化学化工学院陕西西安710119 中北大学材料科学与工程学院山西太原030051 中北大学化学与化工学院山西太原030051

碱金属氧化物因含氧阴离子的种类不同可分为4种类型,即正常氧化物、过氧化物、超氧化物和臭氧化物。依据文献理顺了它们的制备方法,并进行了稳定性的热力学分析。简要介绍了某些氧化物的特殊用途。

关键词：碱金属氧化物制备热力学用途

Research on a Monte Carlo global variance reduction method based on an automatic importance sampling method

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Nuclear Science and Techniques 2024年第5期35卷 200-215页

作者： Yi-sheng Hao Zhen Wu Shen-Shen gao Rui Qiu Hui Zhang Jun-li li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging of Ministry of Education Beijing 100084China Nuctech Company limited Beijing 100084China

Global variance reduction is a bottleneck in Monte Carlo shielding *** global variance reduction problem requires that the statistical error of the entire space is *** study proposed a grid-AIS method for the global variance reduction problem based on the AIS method,which was implemented in the Monte Carlo program *** proposed method was validated using the VENUS-Ⅲ international benchmark problem and a self-shielding calculation *** results from the VENUS-Ⅲ benchmark problem showed that the grid-AIS method achieved a significant reduction in the variance of the statistical errors of the MESH grids,decreasing from 1.08×10^(-2) to 3.84×10^(-3),representing a 64.00% *** demonstrates that the grid-AIS method is effective in addressing global *** results of the selfshielding calculation demonstrate that the grid-AIS method produced accurate computational ***,the grid-AIS method exhibited a computational efficiency approximately one order of magnitude higher than that of the AIS method and approximately two orders of magnitude higher than that of the conventional Monte Carlo method.

关键词： Monte Carlo Global variance reduction Reactor shielding Automatic importance sampling

Influence of the Acoustic liner in Large Eddy Simulation of Longitudinal Thermoacoustic Instability in a Model Annular Combustor

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Journal of Thermal Science 2024年第2期33卷 710-724页

作者： MENG sheng ZHANG Man gao Yi AECC Commercial Aircraft Engine Co. Ltd.Shanghai200241China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China

Although extensive efforts have been made to dampen the thermoacoustic instability,successfully controlling the pressure oscillations in modern gas turbines or aeroengines remains *** influence of the acoustic liner on the longitudinal thermoacoustic mode in a model annular combustor is investigated by Large Eddy Simulation(LES) in this *** result of the self-excited longitudinal thermoacoustic instability without the liner agrees well with the frequency and acoustic analysis of the pressure mode based on experimental *** different bias flow velocities of the liner located downstream of the combustor are then *** results reveal that the existence of the liner influences not only the acoustic field but also the flow *** the bias velocity is large,it leads to intense turbulence-induced fluctuations,and the pressure oscillation is modulated *** shows that the weak coupling between flow and pressure oscillations plays a significant role in the onset of the intermittency of a thermoacoustic *** on the dynamic analysis of the thermoacoustic system with the acoustic liner,this intermittency is caused by the influence of the flow field on the flame-acoustic ***,a low-order modeling method based on Van der Pol(VdP) oscillator with additive stochastic forcing is conducted to reproduce the evolving dynamics of the thermoacoustic *** the numerical cases demonstrated in this work are relatively simpler than those in a practical combustion system,the results are helpful for us to understand the effect of the acoustic liner and show the attractive potential to apply this device to suppress thermoacoustic instability.

关键词： thermoacoustic instability acoustic liner Large Eddy Simulation low-order modeling

Effect of short-time low-temperature austenitizing on microstructure and mechanical properties of DT300 ultra-high strength steel fabricated by laser powder bed fusion

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1763-1777页

作者： Chen-yang Jiang Xiao-qiang li Jin-tao Wang Hao Luo sheng-qing gao sheng-guan Qu Chao Yang National Engineering Research Centre of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640GuangdongChina Institute of New Materials Guangdong Academy of ScienceGuangzhou 510650GuangdongChina

To address the inhomogeneous microstructure and improve the mechanical properties of DT300 ultra-high strength steel specimens fabricated by laser powder bed fusion,different post-heat treatment schedules are *** the increase in austenitizing temperature and time,the migration rate of austenite grain boundaries continuously increases with the dissolution of nano-carbides,and the formation of nano-oxides and twin martensite is also inhibited *** rapid growth in the size of prior austenite grains and martensite laths,as well as the decrease in the content of nano-oxides and twin martensite,led to a rapid decrease in the strength(yield strength and ultimate tensile strength)from HT2 to HTF *** HT1 specimens(austenitizing at 830℃for 30 min,then oil quenching and tempering at 300℃for 120 min and finally air cooling)display excellent mechanical properties of yield strength of 1572 MPa,ultimate tensile strength of 1847 MPa,elongation of 9.84%,and fracture toughness of 106 MPa m^(1/2),which are counterparts to those of conventional DT300 steel forgings after heat treatment.

关键词： DT300 ultra-high strength steel Laser powder bed fusion-Short-time low-temperature austenitizing Microstructure Mechanical property

Trench gate GaN IGBT with controlled hole injection efficiency

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 10-16页

作者： Huang Yi li Yueyue gao sheng Wang Qi liu Bin Han Genquan School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic Science and Engineering Nanjing UniversityNanjing 210008China School of Microelectronics Xidian UniversityXi’an 710126China

In this paper,a novel trench gate gallium nitride(GaN)insulated gate bipolar transistor(GaN IGBT),in which the collector is divided into multiple regions to control the hole injection efficiency,is designed and theoretically *** incorporation of a P+/P-multi-region alternating structure in the collector region mitigates hole injection within the collector *** the device is in forward conduction,the conductivity modulation effect results in a reduced storage of carriers in the drift *** a result,the number of carriers requiring extraction during device turn-off is minimized,leading to a faster turn-off *** results illustrate that the GaN IGBT with controlled hole injection efficiency(CEH GaN IGBT)exhibits markedly enhanced performance compared to conventional GaN IGBT,showing a remarkable 42.2%reduction in turn-off time and a notable 28.5%decrease in turn-off loss.

关键词： gallium nitride insulated gate bipolar transistor(GaN IGBT) hole injection trench gate turn-off loss

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Five-view three-dimensional reconstructionfor ultrafast dynamic imaging of pulsedradiation sources

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Matter and Radiation at Extremes 2024年第2期9卷 63-73页

作者： Jianpeng gao liang sheng Xinyi Wang Yanhong Zhang liang li Baojun Duan Mei Zhang Yang li Dongwei Hei Department of Engineering Physics Tsinghua UniversityBeijing 100084China National Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXi’an 710024China

Multiaxial neutron/x-ray imaging and three-dimensional (3D) reconstruction techniques play a crucial role in gaining valuable insights intothe generation and evolution mechanisms of pulsed radiation sources. Owing to the short emission time (∼200 ns) and drastic changes of thepulsed radiation source, it is necessary to acquire projection data within a few nanoseconds in order to achieve clear computed tomography3D imaging. As a consequence, projection data that can be used for computed tomography image reconstruction at a certain moment are oftenavailable for only a few angles. Traditional algorithms employed in the process of reconstructing 3D images with extremely incomplete datamay introduce significant distortions and artifacts into the final image. In this paper, we propose an iterative image reconstruction methodusing cylindrical harmonic decomposition and a self-supervised denoising network algorithm based on the deep image prior method. Weaugment the prior information with a 2D total variation prior and a 3D deep image prior. Single-wire Z-pinch imaging experiments have beencarried out at Qin-1 facility in five views and four frames, with a time resolution of 3 ns for each frame and a time interval of 40 ns betweenadjacent frames. Both numerical simulations and experiments verify that our proposed algorithm can achieve high-quality reconstructionresults and obtain the 3D intensity distribution and evolution of extreme ultraviolet and soft x-ray emission from plasma.

关键词： frames image sources

吴起油田白河北部长8储层特征及其控制因素研究

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地下水 2024年第1期46卷 144-147页

作者：张文奕高胜利廖保江孙兵华白江西安石油大学地球科学与工程学院/陕西省油气成藏地质学重点实验室陕西西安710065 延长油田股份有限公司吴起采油厂陕西延安717600

为对吴起油田长8地区的储层特征存进行进一步深入的了解,利用研究区内高压压汞、岩石薄片、铸体薄片以及物性特征等资料,对吴起油田白河北部长8储层的岩石学特征、孔隙类型及结构、孔渗特征等进行研究,并对可能影响储层物性的因素进行讨... 详细信息

为对吴起油田长8地区的储层特征存进行进一步深入的了解,利用研究区内高压压汞、岩石薄片、铸体薄片以及物性特征等资料,对吴起油田白河北部长8储层的岩石学特征、孔隙类型及结构、孔渗特征等进行研究,并对可能影响储层物性的因素进行讨论,得出:沉积微相和成岩作用是影响该储层的主要因素。储层特征:分流间湾、下分流河道和远砂坝是白河北部长8沉积微相主要的存在形式,其河口坝的发育程度较低,以浅灰、灰色细粒长石砂岩和岩屑长石砂岩为主要的岩石类型,研究区孔隙类型以岩屑溶孔、长石溶孔、粒间孔隙居多,晶间孔的数量较少,可见少量的微裂隙。总体上看长8储层的类型属特低孔、超低渗致密储层。分析研究范围各小层的物性可得,其中长8_(2)^(2)物性最好。

关键词：白河油区延长组长8 储层特征控制因素

Strategy for Detecting Systemic Treatment Sensitivity of Primary liver Cancer Based on a Novel Infrared-emissive Organic Nanoparticle

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Chemical Research in Chinese Universities 2024年第1期40卷 145-152页

作者： WU Jun li Yongzhi QIN Hanjiao gao Ying YANG Bing sheng Jiyao ZHANG Xuewen Department of Hepatobiliary and Pancreatic Surgery the Second Hospital of Jilin UniversityChangchun130022P.R.China Department of Radiation Oncology the Second Hospital of Jilin UniversityChangchun130022P.R.China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun130012P.R.China

In this study,we synthesized an organic material with near-infrared emission capabilities:4-(2-(4-(9-(4-(diphenylamino)phenyl)naphtho[2,3-c][1,2,5]thiadiazol-4-yl)phenyl)-1H-phenol-1-ylidene)malononitrile(TPA).Furthermore,TPA-PEG2000 fluorescent nanoparticles were prepared via coating the shells with ***-PEG2000 exhibited strong near-infrared emission near 700 nm,with a photoluminescence quantum yield of 15.09%,indicating a high emission *** biology experiments have confirmed its low toxicity and excellent *** cholesterol and phospholipid levels in liver cancer cell membranes with low sensitivity or high drug resistance lead to increased rigidity,reduced membrane fluidity,reduced endocytic efficiency,and reduced ***,the uptake of TPA-PEG2000 nanoparticles into cells and the near-infrared fluorescence intensity can be used to evaluate the sensitivity of systemic liver cancer treatment in a simple and efficient manner.

关键词： Nanoparticle Near-infrared Fluorescence Systemic treatment sensitivity Cell membrane fluidity