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Fracture sealing performance of granular lost circulation materials at elevated temperature:A theoretical and coupled CFD-DEM simulation study

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Petroleum Science 2024年第1期21卷 567-581页

作者： Chong Lin Qi-Cong xu Lie-Xiang Han Gao Li Hai He Hong-Ling Zhou ji-Ping She CCDC Drilling&Production Technology Research Institute Guanghan618300SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina College of Materials Science and Engineering Chongqing UniversityChongqing400044China State Key Lab of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology) Chengdu610059SichuanChina College of Energy Chengdu University of TechnologyChengdu610059SichuanChina

Lost circulation is a common downhole problem of drilling in geothermal and high-temperature,high-pressure(HTHP)*** circulation material(LCM)is a regular preventive and remedial measure for lost ***,conventional LCMs seem ineffective in high-temperature *** may be due to the changes in the mechanical properties of LCMs and their sealing performance under high-temperature *** understand how high temperature affects the fracture sealing performance of LCMs,we developed a coupled computational fluid dynamics-discrete element method(CFD-DEM)model to simulate the behavior of granular LCMs in *** summarized the literature on the effects of high temperature on the mechanical properties of LCMs and the rheological properties of drilling *** conducted sensitivity analyses to investigate how changing LCM slurry properties affected the fracture sealing efficiency at increasing *** results show that high temperature reduces the size,strength,and friction coefficient of LCMs as well as the drilling fluid ***,softer,and less frictional LCM particles have lower bridging probability and slower bridging *** particles tend to form dual-particle bridges rather than single-particle *** result in a deeper,tighter,but unstable sealing *** drilling fluid viscosity leads to faster and shallower sealing zones.

关键词： Geothermal well drilling HTHP formationLost circulation material CFD-DEM Fracture sealing

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Single-cluster electronics using metallic clusters:Fabrications,regulations,and applications

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Nano Research 2024年第1期17卷 65-78页

作者： Caiyun Wei Wei xu Shurui ji Ruiyun Huang Junyang Liu Wenqiu Su jie Bai jiale Huang Wenjing Hong State Key Laboratory of Physical Chemistry of Solid Surfaces National Engineering Research Centre of Chemicals for Electronic ManufacturingCollege of Chemistry and Chemical Engineering&Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)Xiamen UniversityXiamen 361005China

Metallic clusters,ranging from 1 to 2 nm in size,have emerged as promising candidates for creating nanoelectronic devices at the single-cluster *** the intermediate quantum properties between metals and semiconductors,these metallic clusters offer an alternative pathway to silicon-based electronics and organic molecules for miniaturized electronics with dimensions below 5 *** progress has been made in studies of single-cluster electronic ***,a clear guide for selecting,synthesizing,and fabricating functional single-cluster electronic devices is still *** review article provides a comprehensive overview of single-cluster electronic devices,including the mechanisms of electron transport,the fabrication of devices,and the regulations of electron transport ***,we discuss the challenges and future directions for single-cluster electronic devices and their potential applications.

关键词： single-cluster junctions electronic properties electron transport metallic clusters structure regulation

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Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 736-752页

作者： DING Gaoming ji Genyuan YAN Guolong xu Yongzhong WANG Kunming XIAO Chun WANG Quanle GUO Dongbao China National Administration of Coal Geology Beijing 100038China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China China Gold Group Geological Co. Ltd.Beijing 100011China China Gold Group ZhongYuan Mining Co. Ltd.SanmenxiaHenan 472000China Lanzhou Mineral Exploration Institute of Gansu Nonferrous Metal Geological Exploration Bureau Lanzhou 730046China

Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep *** approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking *** Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China *** borehole data on oreforming elements underpin deep geochemical *** methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration.

关键词： 3D geochemical model ore-forming elements geostatistics deep mineralization prediction Yechangping Mo deposit

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Nd:YAG water mist laser treatment for giant gestational gingival tumor: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1974-1979页

作者： Hong-Yu Chen Jun-ji xu Xiu-Lin Chang Pei Wu Department of Stomatology Women and Children's Hospital Affiliated to Ningbo UniversityNingbo 315012Zhejiang ProvinceChina

BACKGROUND This case of gestational gingival tumor is huge and extremely rare in clinical *** the growth location of this gingival tumor is in the upper anterior tooth area,it seriously affects the pregnant woman's speech and food,causing great pain to the *** use of Nd:YGA water mist laser to remove the gingival tumor resulted in minimal intraoperative bleeding,minimal adverse reactions,and good postoperative healing,which is worthy of clinical promotion and *** SUMMARY The patient,a pregnant woman,reported a large lump in her mouth on the first day of postpartum *** on medical history and clinical examination,the diagnosis was diagnosed as gestational gingival *** pathological biopsy also confirmed this *** use of Nd:YAG water mist laser to remove the tumor resulted in minimal intraoperative bleeding,clear surgical field of view,short surgical time,and good postoperative *** In comparison to traditional surgery,Nd:YAG water mist laser surgery is minimally invasive,minimizes cell damage,reduces bleeding,ensures a clear field of vision,and virtually eliminates postoperative edema,carbonization,and the risk of cross *** has unique advantages in oral soft tissue surgery for pregnant ***,the clinical application of Nd:YAG water mist laser for the treatment of gestational gingival tumors is an ideal choice.

关键词： Gestational gingival tumor Nd:YAG water mist laser Granulomatous gingival tumor Minimally invasive dentistry Pregnancy related diseases Oral soft tissue surgery Case report

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Quality assessment of friction-stir-welded aluminum alloy welds via three-dimensional force signals

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Advances in Manufacturing 2024年第1期12卷 61-75页

作者： ji-Hong Dong Yi-Ming Huang jia-Lei Zhu Wei Guan xu-Kai Ren Huan-Wei Yu Lei Cui Beijing Institute of Petrochemical Technology Beijing102617People’s Republic of China Beijing Academy of Safety Engineering and Technology Beijing102617People’s Republic of China AVIC Manufacturing Technology Institute Beijing100024People’s Republic of China Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin300350People’s Republic of China Shaoxing Special Equipment Testing Institute Shaoxing Key Laboratory of Special Equipment Intelligent Testing and EvaluationShaoxing312071ZhejiangPeople’s Republic of China

An online detection technology must be developed for realizing the real-time control of friction stir *** this study,the three-dimensional force exerted on a material during friction stir welding was collected synchronously and the relationship between the forces and welding quality was *** results indicated that the fluctuation period of the traverse force was equal to that of the lateral force during the stable welding *** phase difference between two horizontal forces wasπ/*** values of the horizontal forces increased with welding speed,whereas their amplitudes remained the *** proposed force model showed that the traverse and lateral forces conformed to an elliptical curve,and this result was consistent with the behavior of the measured *** variational mode decomposition was used to process the plunge *** intrinsic mode function that represented the real fluctuation in the plunge force varied at the same frequency as the spindle rotational *** tunnel defects occurred,the fluctuation period features were consistent with those obtained during normal welding,whereas the ratio parameter defined in this study increased significantly.

关键词： Friction stir welding(FSW) Three-dimensional force model Variational mode decomposition Tunnel defect

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Nitrogen-doped titanium dioxide/schwertmannite nanocomposites as heterogeneous photo-Fenton catalysts with enhanced efficiency for the degradation of bisphenol A

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Journal of Environmental Sciences 2024年第9期143卷 1-11页

作者： Xing-Xing Qiao Yu-Hang xu Xiang-ji Liu Sai-Le Chen Zhou Zhong Ya-Feng Li jian Lü Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Potential health risks related to environmental endocrine disruptors(EEDs)have aroused research hotspots at the forefront of water treatment ***,nitrogen-doped titanium dioxide/schwertmannite nanocomposites(N-TiO_(2)/SCH)have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton *** to the sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion induced by photoelectrons,as-prepared N-TiO_(2)/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A(BPA;ca.100% within 60 min under visible irradiation)in a wide pH range of 3.0-7.8,which is significantly higher than that of the pristine schwertmannite(ca.74.5%)or N-TiO_(2)(ca.10.8%).In this photo-Fenton system,the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Moreover,the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical *** work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts,but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.

关键词： Titanium dioxide Schwertmannite Fenton reaction Environmental endocrine disruptors Photocatalysis

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Achieving Ultra-Broad Microwave Absorption Bandwidth Around Millimeter-Wave Atmospheric Window Through an Intentional Manipulation on Multi-Magnetic Resonance Behavior

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Nano-Micro Letters 2024年第9期16卷 291-307页

作者： Chuyang Liu Lu xu xueyu Xiang Yujing Zhang Li Zhou Bo Ouyang Fan Wu Dong‑Hyun Kim Guangbin ji School of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016JiangsuPeople’s Republic of China School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Physics Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Physics Chungbuk National UniversityCheongju 28644South Korea Department of Chemistry School of ScienceTianjin UniversityTianjin 300072People’s Republic of China

The utilization of electromagnetic waves is rapidly advancing into the millimeter-wave frequency range,posing increasingly severe challenges in terms of electromagnetic pollution prevention and radar ***,existing millimeter-wave absorbers are still inadequate in addressing these issues due to their monotonous magnetic resonance *** this work,rare-earth La^(3+)and non-magnetic Zr^(4+)ions are simultaneously incorporated into M-type barium ferrite(BaM)to intentionally manipulate the multi-magnetic resonance *** leveraging the contrary impact of La^(3+)and Zr^(4+)ions on magnetocrystalline anisotropy field,the restrictive relationship between intensity and frequency of the multi-magnetic resonance is successfully *** magnetic resonance peak-differentiating and imitating results confirm that significant multi-magnetic resonance phenomenon emerges around 35 GHz due to the reinforced exchange coupling effect between Fe^(3+)and Fe^(2+)***,Mosbauer spectra analysis,first-principle calculations,and least square fitting collectively identify that additional La^(3+)doping leads to a profound rearrangement of Zr^(4+)occupation and thus makes the portion of polarization/conduction loss increase *** a consequence,the La^(3+)-Zr^(4+)co-doped BaM achieves an ultra-broad bandwidth of 12.5+GHz covering from 27.5 to 40+GHz,which holds remarkable potential for millimeter-wave absorbers around the atmospheric window of 35 GHz.

关键词： Microwave absorption Ultra-broad bandwidth M-type barium ferrite Magnetocrystalline anisotropy field Multimagnetic resonance

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Heteroatom doping regulates the catalytic performance of singleatom catalyst supported on graphene for ORR

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Nano Research 2024年第3期17卷 1086-1093页

作者： ji-Kai Sun Yu-Wei Pan Meng-Qian xu Lei Sun Shaolong Zhang Wei-Qiao Deng Dong Zhai Institute of Molecular Sciences and Engineering Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Replacing fossil fuels with fuel cells is a feasible way to reduce global energy shortages and environmental ***,the oxygen reduction reaction(ORR)at the cathode has sluggish kinetics,which limits the development of fuel *** is significant to develop catalysts with high catalytic activity of *** single-atom catalysts(SACs)of Pt supported on heteroatom-doped graphene are potential candidates for *** we studied the SACs of Pt with different heteroatoms doping and screened out Pt-C_(4) and Pt-C_(3)O_(1) structures with only 0.13 V overpotential for ***,it is found that B atoms doping could weaken the adsorption capacity of Pt,while N or O atoms doping could enhance *** regularity was verified on Fe *** the electronic interaction analysis between Pt and adsorbate,we explained the mechanism of this regularity and further proposed a new descriptor named corrected d-band center(ε_(d-corr))to describe *** descriptor is an appropriate reflection of the number of free electrons of the SACs,which could evaluate its adsorption *** work provides a purposeful regulatory strategy for the design of ORR catalysts.

关键词： single-atom catalyst(SAC) oxygen reduction reaction(ORR) heteroatom doping corrected d-band center descriptor

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Solar image reconstruction method under atmospheric turbulence at Fuxian Lake Solar Observatory

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Astronomical Techniques and Instruments 2024年第2期1卷 128-139页

作者： Sizhong Zou Zhenyu jin Kaifan ji Jun xu Lei yang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China University of Chinese Academy of Sciences Beijing 101408China

Strong atmospheric turbulence reduces astronomical seeing,causing speckle images acquired by ground-based solar telescopes to become blurred and *** distortion in speckle images impedes image phase deviation in the speckle masking reconstruction method,leading to the appearance of spurious imaging *** only on linear image degradation principles to reconstruct solar images is *** solve this problem,we propose the multiframe blind deconvolution combined with non-rigid alignment(MFBD-CNRA)method for solar image *** consider image distortion caused by atmospheric turbulence and use non-rigid alignment to correct pixel-level distortion,thereby achieving nonlinear constraints to complement image intensity *** creating the corrected speckle image,we use the linear method to solve the wavefront phase,obtaining the target *** verify the effectiveness of our method results,compared with others,using solar observation data from the 1 m new vacuum solar telescope(NVST).This new method successfully reconstructs high-resolution images of solar observations with a Fried parameter r0 of approximately 10 cm,and enhances images at high *** r0 is approximately 5 cm,the new method is even more *** reconstructs the edges of solar graining and sunspots,and is greatly enhanced at mid and high frequency compared with other *** confirm the effectiveness of this method,with respect to both nonlinear and linear constraints in solar image *** provides a suitable solution for image reconstruction in ground-based solar observations under strong atmospheric turbulence.

关键词： Astronomical seeing Solar telescopes Solar observatories Astronomy image processing Phase error Deconvolution

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l-麻黄碱的合成工艺改进

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华西药学杂志 2006年第2期21卷 162-164页

作者：张莹许激扬中国药科大学生物化学教研室江苏南京210009

目的合成l-麻黄碱并改进工艺。方法以苯丙酮为起始原料,经溴代、甲胺化、还原、拆分等反应制得l-麻黄碱。结果经红外、核磁、旋光检验,得到结构确定、旋光合格的产品。结论改进后的方法合成简单、可行。

关键词：麻黄碱合成拆分

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