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波叠加声场重构精度的影响因素分析

物理学报 2008年第7期57卷 4258-4264页

作者：李加庆陈进杨超贾文强上海交通大学振动、冲击、噪声研究所上海200240

波叠加法是利用等效源的思想来求解声辐射问题的一种数值方法.其原理并没有确切地规定如何配置等效源.正由于这些不确切性的存在,当将它应用到声场重构时,有必要检验重构的准确性,分析影响重构精度的各种因素,目的是通过分析而获得一些... 详细信息

波叠加法是利用等效源的思想来求解声辐射问题的一种数值方法.其原理并没有确切地规定如何配置等效源.正由于这些不确切性的存在,当将它应用到声场重构时,有必要检验重构的准确性,分析影响重构精度的各种因素,目的是通过分析而获得一些提高重构精度的规律.通过理论分析和数值仿真,分析了各因素对重建准确性的影响.证明等效源必须配置在辐射体内部,而且最好能与辐射体表面共形;但测量面并不需要与辐射体表面共形,而且也不需要在近场测量;还发现,Tikhonov和TSVD正则化方法很适合与波叠加法结合用于声场重构.依据这些规律能更好地应用波叠加法进行声场重构,也将拓宽其应用范围.

关键词：声场重构波叠加法误差影响因素正则化方法

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： jia Zhao Taixi Feng Guimin Lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

Primary parenchymal squamous cell carcinoma of the kidney:A case report

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World Journal of Clinical Cases 2025年第4期13卷 34-40页

作者： Zhi-Hui Zheng Bo Shao chao-Min Xu Ke Wang jia-Zhu Wen Li-Kang Luo jia-Cheng Guan Department of Ultrasound The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Radiology Shulan(Quzhou)HospitalQuzhou 324000Zhejiang ProvinceChina Department of Radiology The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Pathology The Second people’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina

BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases *** SUMMARY This study reports a 51-year-old man with primary SCC of the renal *** patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross *** antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated *** patient underwent laparoscopic unilateral nephrectomy and lymph node *** pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and *** pathological stage was *** months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena *** patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease *** We report a case of primary SCC of the renal parenchyma,a rare renal *** clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis *** to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.

关键词： Renal tumor Renal parenchyma Squamous cell carcinoma Renal calculi Computed tomography Case report

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单一规格物体二维矩形条带装箱问题解法研究

成组技术与生产现代化 2017年第2期34卷 6-8页

作者：胡锦超贾春玉宁波工程学院经济与管理学院浙江宁波315211

为了克服用启发式算法及智能搜索法解决单一规格物体二维矩形条带装箱问题耗时过长的缺陷,提出了新的解法和思路.用线性规划法分别在2个维度求最优解,以最好的方案作为近似最优解,可大幅度缩短求解时间,获得满意的近似最优解.

关键词：单一规格装箱问题启发式算法线性规划解法智能搜索法

16.48% Efficient solution-processed CIGS solar cells with crystal growth and defects engineering enabled by Ag doping strategy

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Journal of Energy Chemistry 2025年第1期100卷 59-65页

作者： Mengyu Xu Shaocong Yan Ting Liang jia jia Shengjie Yuan Dongxing Kou Zhengji Zhou Wenhui Zhou Yafang Qi Yuena Meng Litao Han Sixin Wu Key Laboratory for Special Functional Materials of MOE National & Local Joint Engineering Research Centre for High-efficiency Display and Lighting Technology School of Nanoscience and Materials Engineering Henan University

Solution-processed Cu（In,Ga）Se2（CIGS） solar cells suffer from serious carrier recombination and power conversion efficiency（PCE） loss because of the poor film properties and easy formation of ***, we propose Ag&Se co-selenization strategy to enhance the crystallization and passivate harmful defects of the CIGS films. The formation of Ag-Se phase during the selenization process enables the formation of large grains and suppresses the deep level defects. It is found that Ag doping can enlarge the depletion region width, lower the Urbach energy and prolong the carrier lifetime. As a result, a champion solution-processed CIGS solar cell presents a high efficiency of 16.48% with the highly improved opencircuit voltage（VOC） of 662 m V and fill factor（FF） of 75.8%. This work provides an efficient strategy to prepare high quality solution-processed CIGS films for high-performance CIGS solar cells.

关键词： CIGS solar cells Solution-processed method Ag doping Crystal growth Defects engineering

Enhanced post-combustion CO2 capture and direct air capture by plasma surface functionalization of graphene adsorbent

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Journal of Energy Chemistry 2025年第1期100卷 653-664页

作者： Rahul Navik Eryu Wang Xiao Ding Huang Yunyi Yiyu Liu jia Li Guangdong-Hong Kong Joint Laboratory for Carbon Neutrality Jiangmen Laboratory of Carbon and Science and Technology Guangzhou HKUST Fok Ying Tung Research Institute The Hong Kong University of Science and Technology (Guangzhou) Carbon Neutrality and Climate Change Thrust Society Hub The Hong Kong University of Science and Technology (Guangzhou) Stoddart Institute of Molecular Science Department of Chemistry Zhejiang University

Graphene has enormous potential to capture CO2due to its unique properties and ***,graphene-based adsorbents have drawbacks of lower CO2adsorption capacity and poor *** work demonstrates a one-step rapid and sustainable N2/H2plasma treatment process to prepare graphene-based sorbent material with enhanced CO2adsorption *** treatment directly enriches amine species,increases surface area,and improves textural *** CO2adsorption capacity increases from 1.6 to 3.3 mmol/g for capturing flue gas,and from 0.14 to 1.3 mmol/g for direct air capture （DAC）.Importantly,the electrothermal property of the plasma-modified aerogels has been significantly improved,resulting in faster heating rates and significantly reducing energy consumption compared to conventional external heating for regeneration of *** aerogels display improved selectivity of 42 and 87 after plasma modification for 5 and 10 min,*** plasma-treated aerogels display minimal loss between 17%and 19% in capacity after 40 adsorption/desorption cycles,rendering excellent *** N2/H2plasma treatment of adsorbent materials would lower energy expenses and prevent negative effects on the global economy caused by climate change.

关键词： Carbon neutrality CO 2 capture Climate change Plasma treatment Graphene aerogel

Evaluation of Mining Titles Based on Option-Pricing Model

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Journal of China University of Mining and Technology 2006年第1期16卷 33-36页

作者： chao Kun jia jin-ling School of Management China University of Mining ＆ Technology Beijing 100083 China

Limitations exist in applying discounted cash flow and analogy sales methods to evaluate mining titles. In order to find a more appropriate way of evaluating mining titles, the Black-Scholes model is discussed in this paper. The authors pay particular attention to the determination of the time to maturity of the option on the basis of characteristics of the mining industry, pointing out that a reasonable time to maturity of the option should be the remaining time after deducting the essential time, needed by exploitation of the mineral resources within the mining property, from the life of the mining title. Several conclusions, related to the exercise of mineral resource management, are drawn from a case study analysis; extending the life of a mining title within a certain range could increase the revenue to the seller of the mining title. Application of the Black-Scholes model to evaluate mining titles would encourage an expansion of the scale of production.

关键词： Mining titles Option evaluation method Time to maturity of option

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He jia Zheng Hongming Bai jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

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煤基乙二醇产品精制实验研究

天然气化工—C1化学与化工 2017年第3期42卷 51-55页

作者：穆仕芳张士祥陈创新尚如静魏灵朝蒋元力河南能源化工集团研究院有限公司河南郑州450046 中国科学院山西煤炭化学研究所煤转化国家重点实验室山西太原030001 河南能源化工集团新乡永金化工有限公司河南获嘉453800 河南能源化工集团中新化工有限公司河南获嘉453800

采用活性炭液相静态吸附法对煤基乙二醇产品进行精制,研究活性炭改性方法以及原料来源对煤基乙二醇紫外透光率和产品色度的影响,结果表明木质炭和椰壳炭组合改性吸附后,煤基乙二醇产品品质明显提升,效果优于催化加氢。在此基础上研究放... 详细信息

采用活性炭液相静态吸附法对煤基乙二醇产品进行精制,研究活性炭改性方法以及原料来源对煤基乙二醇紫外透光率和产品色度的影响,结果表明木质炭和椰壳炭组合改性吸附后,煤基乙二醇产品品质明显提升,效果优于催化加氢。在此基础上研究放置时间和测试过程中参比水的影响。

关键词：煤基乙二醇产品精制活性炭液相吸附催化加氢放置时间参比水