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EFFEcT OF LASER INPUT ENERGY ON AuSn_x INTERMETALLIc cOMPOUNDS FORMATION IN SOLDER JOINTS WITH DIFFER-ENT THIcKNESS OF Au SURFAcE FINISH ON PADS

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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 183-190页

作者： W. Liu c.q. wang Y.H. Tian M.Y. Li Department of Electronics Packaging Technology State Key Lab of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China Shenzhen Graduate School of Harbin Institute of Technology Shenzhen 518055 China

Formation of AuSnx intermetallic compounds （IMcs） in laser reflowed solder joints was investigated. The results showed that few IMcs formed at the solder/0. 1μm Au interface. Needlelike AuSn4 IMcs were observed at the solder/0.5μm Au interface. In Sn-2.0Ag-O,75cu-3,0Bi and Sn-3.5Ag-O.75cu solder joints, when the laser input energy was increased, AuSn4 IMcs changed .from a layer to needlelike or dendritic distribution at the solder/0.9μm Au interface. As for the solder joints with 4.0 μm thickness of Au surface finish on pads, AuSn4 , AuSnx, AuSn IMcs, and Au2Sn phases formed at the interface. Moreover, the content of AuSnx IMcs, such as, AuSn4 and AuSn2, which contained high Sn concentration, would become larger as the laser input energy increased. In the Sn-37Pb solder joints with 0.9 μm or 4.0 μm thickness of the Au surface finish on pads, AuSn4 IMcs were in netlike distribution. The interspaces between them were filled with Pb-rich phases.

关键词： Laser soldering Inlermetallics Au films

Anomalous open orbits in Hofstadter spectrum of chern insulator

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Science china(Physics,Mechanics & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 143-148页

作者： Haijiao Ji Peng Zhou Noah F.q.Yuan Hua Jiang Haiwen Liu X.c.Xie center for Advanced quantum Studies Department of Physics Beijing Normal University Tsung-Dao Lee Institute Shanghai Jiao Tong University Department of Mathematics UC Berkeley Institute for Nanoelectronic Devices and quantum computing Fudan University International center for quantum Materials School of Physics Peking University Hefei National Laboratory

The nontrivial band topology of chern insulator can enrich the content of its Hofstadter butterfly spectra, which is closely related to recent experiments in twisted bilayer graphene and cold atom systems. We investigate the Hofstadter spectrum for various models of chern insulators under a rational flux φ0/q, here φ0=h/e and q being an integer. We find the number of splitting subbands is |q-c| with c denoting the chern number of parent band. Importantly, anomalous open-orbital subbands with chern numbers q-1 and-q-1 emerge unexpectedly, which are beyond the parameter window（-q/2, q/2） of the Diophantine equation studied by Thouless-Kohmoto-Nightingale-den Nijs [Phys. Rev. Lett. 49, 405（1982）]. The emergence of anomalous open orbits can be traced by analyzing the evolution of the Hofstadter spectrum, identifying as a new type of topological phase transition. These novel findings not only pinpoint the peculiar Hofstadter spectrum of chern insulator, but also provide routes to study exotic characteristics beyond the Landau level physics.

关键词： Hofstadter spectrum topological phase transition open orbit

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[correlation and predictive value analysis of systemic inflammation grade and plaque stability in patients with carotid artery stenosis]

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Zhonghua yi xue za zhi 2025年第7期105卷 537-543页

作者： q H wang c Tang J cai Y M wang L Zheng B Zhao L Z Fan q Ni Z S Liang T qiao Department of Vascular Surgery Nanjing Drum Tower Hospital Affiliated Hospital of Medical School Nanjing University Nanjing 210008 China. Department of Vascular Surgery Nanjing Drum Tower Hospital Clinical College of Nanjing University of Traditional Chinese Medicine Chinacal College of Nanjing University of Traditional Chinese Medicine Nanjing 210008 China. Department of Geriatrics Nanjing Drum Tower Hospital Affiliated Hospital of Medical School Nanjing University Nanjing 210008 China.

To analyze the correlation between the systemic inflammation score (SIG) and plaque stability in patients with carotid artery stenosis, and to evaluate the predictive value. The clinical data of 149 patients with carotid artery stenosis who were hospitalized in Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School from January 2019 to October 2023 were retrospectively analyzed, including 124 males and 25 females, aged (68.2±8.9) years. According to the results of pathological analysis of specimens after carotid endarterectomy, the patients were divided into plaque stable group (=70) and plaque vulnerable group (=79). After preoperative blood biochemical indexes were collected and neutrophil-lymphocyte ratio and modified glasgow prognostic score(mGPS) were calculated, the SIG was calculated together. The multivariate logistic regression model was used to analyze the correlative factors of plaque stability in patients with carotid artery stenosis, and the receiver operating characteristic (ROc) curve was used to analyze the predictive value of SIG for plaque stability in patients with carotid artery stenosis. The proportion of patients with a history of diabetes in the plaque vulnerable group [36.7% (29/79) vs 20.0% (14/70)] and IL-6 [0.43 (0.31, 0.64) vs 0.34 (0.17, 0.44) ng/L] were higher than those in the plaque stabilization group(both core and SIG score of the plaque vulnerable group were higher than those of the plaque stabilization group (both c regression model showed that diabetes history (=2.82, 95%: 1.23-6.48), high interleukin-6 (IL-6) level (=1.16, 95%: 1.01-1.33), and high SIG scores [with SIG=0 as the reference, (SIG=1)=1.76,95%:1.21-2.41; (SIG=2)=2.21,95%:1.51-3.01; (SIG=3)=4.47,95%:2.42-6.52; (SIG=4)=3.19,95%:2.01-4.36] were risk factors for plaque instability in patients with carotid artery stenosis. The results of ROc curve analysis showed that when the S

关键词：颈动脉狭窄动脉粥样硬化系统性炎症评分斑块稳定性

The Dynamics of a Stochastic SEITR Model for Tuberculosis with Incomplete Treatment

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 99-113页

作者： Xiao-dong wang Kai wang Department of Medical Engineering and Technology Xinjiang Medical UniversityUrumqiXinjiang 830017China

In this paper,a stochastic SEITR model is formulated to describe the transmission dynamics of tuberculosis with incompletely *** conditions for the existence of a stationary distribution and extinction are *** addition,numerical simulations are given to illustrate these analytical *** and numerical results show that large environmental perturbations can inhibit the spread of tuberculosis.

关键词： tuberculosis stationary distribution extinction

疱疹早期应用度洛西汀预防带状疱疹后神经痛的疗效:一项随机对照研究

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中国疼痛医学杂志 2025年第1期31卷 13-14页

作者： Zhao c Zhang T Zhu q 赵春美(译) 不详首都医科大学附属北京天坛医院疼痛科

经典抗焦虑抑郁药物-度洛西汀为带状疱疹后神经痛(postherpetic neuralgia,PHN)的一线治疗药物。本研究首次提出在带状疱疹出疱急性期预防性口服度洛西汀有望预防PHN的发生,纳入疼痛VAS评分≥4、带状疱疹出疱72 h内的750例病人,随机分... 详细信息

经典抗焦虑抑郁药物-度洛西汀为带状疱疹后神经痛(postherpetic neuralgia,PHN)的一线治疗药物。本研究首次提出在带状疱疹出疱急性期预防性口服度洛西汀有望预防PHN的发生,纳入疼痛VAS评分≥4、带状疱疹出疱72 h内的750例病人,随机分为对照组和度洛西汀组。对照组接受常规临床治疗,度洛西汀组在常规治疗基础上口服度洛西汀。主要结局指标为12周时PHN的发生率。次要结局指标包括3、4、8周VAS评分>0的人数,以及4、8、12周VAS评分≥3的人数、生活质量评分、病人总体变化评分、睡眠质量评分等。结果表明,度洛西汀组的PHN发生率与对照组相比无显著差异,度洛西汀组第3、4、8周VAS评分>0的人数,以及4、8和12周VAS评分≥3的人数显著少于对照组。度洛西汀组病人的生活质量评分、病人总体变化评分、睡眠质量评分均显著优于对照组。虽然本研究为阴性结果,但预防性口服度洛西汀仍可以避免5.9%的带状疱疹病人发展成为PHN,因此具有一定的临床意义。

关键词：带状疱疹后神经痛度洛西汀结局指标阴性结果一线治疗药物早期应用随机对照研究带状疱疹病

Exhumation and Preservation of the Yangchuling Porphyry W-Mo Deposit in the Jiangnan Tungsten Ore Belt,South china:Insights from(U-Th)/He and Fission Track Dating

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Journal of Earth Science 2025年第1期36卷 46-56页

作者： Yue Sun Ying wang Jianzhang Pang Samuel c.Boone Minting Wu chongjian Shao Wei Liu Jiangxi Provincial Key Laboratory of Genesis and Prospect for Strategic Minerals School of Earth ScienceEast China University of TechnologyNanchang330013China Institute of Geology china Earthquake Administration Beijing100029China School of Geography Earth and Atmospheric Sciences The University of MelbourneMelbourneVIC3010Australia Department of Earth Sciences The University of AdelaideAdelaideSA5005Australia Jiangxi Duchang JinDing Tungsten cO. Ltd.Jiujiang332611China

The Yangchuling porphyry W-Mo deposit(YPWD),located in the Jiangnan porphyryskarn tungsten ore belt,is one of the most important and large-scale porphyry W-Mo deposits in South *** previous zircon U-Pb and molybdenite Re-Os data suggest that Yangchuling WMo ore bodies formed almost simultaneously with granodiorite and monzogranitic porphyry at~150–144 Ma,their post emplacement history remains poorly understood,making their preservation status at depth *** this paper,new zircon and apatite(U-Th)/He and apatite fission track(ZHe,AHe and AFT,respectively)data of one hornfels and five intrusive rocks from a 1000-meter borehole are ***,together with new inverse thermal history models and previous geochronological data,help elucidate the post-diagenetic exhumation history and preservation status of the Yangchuling porphyry W-Mo *** general,ZHe and AHe ages decrease gradually from the near surface downwards and have relatively little intra-sample variation,ranging from 133 to 73Ma and 67 to 25 Ma,*** four granodiorites yield similar AFT ages that range from 63 to 55 Ma with mean track lengths varying from 12.2±0.7 to 12.6±0.5μ*** history modelling indicates that the Yangchuling ore district experienced slow,monotonic cooling since the ***-depth relationships are interpreted as recording~3.7±0.8 km of cretaceous-recent exhumation in response to regional extension throughout South china thought to have been driven by subduction retreat of the Paleo-Pacific *** of estimated net exhumation and previous metallogenic depth of~4–5 km suggests that W-Mo ore bodies could still exist at depths of up to~1.3±0.8 km relative to Earth surface in the YPWD *** of the YPWD is attributed to the limited amount of regional denudation during the Late cretaceous and cenozoic.

关键词： (U-Th)/He fission track ore preservation thermochronology Yangchuling porphyry W-Mo deposit

Exploring the diversity of dissolved organic matter(DOM)properties and sources in different functional areas of a typical macrophyte-derived lake combined with optical spectroscopy and FT-IcR MS analysis

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Journal of Environmental Sciences 2025年第1期147卷 462-473页

作者： Kun wang Haoyu Ren Shengwu Yuan Xia Jiang Pengfei wang college of Water Sciences Beijing Normal UniversityBeijing 100875China National Engineering Laboratory of Lake Pollution control and Ecological Restoration Chinese Research Academy of Environmental SciencesBeijing 100012China

Lake Baiyangdian is one of china’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication *** organic matter(DOM)was a huge carbon pool and its abundance,property,and transformation played important roles in the biogeochemical cycle and energy flow in lake *** this study,Lake Baiyangdian was divided into four distinct areas:Unartificial Area(UA),Village Area(VA),Tourism Area(TA),and Breeding Area(BA).We examined the diversity of DOM properties and sources across these functional *** findings reveal that DOM in this lake is predominantly composed of protein-like substances,as determined by excitation-emission matrix and parallel factor analysis(EEM-PARAFAc).Notably,the exogenous tyrosine-like component c1 showed a stronger presence in VA and BA compared to UA and ***-resolution mass spectrometry(FT-IcR MS)unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds,suggesting that macrophytes significantly influence the material structure of *** properties exhibited specific associations with water quality indicators in various functional areas,as indicated by the Mantel *** connections between DOM properties and NO_(3)-N andNH3-Nwere more pronounced in VA and BA than in UA and *** results underscore the viability of using DOM as an indicator for more precise and scientific water quality management.

关键词： Dissolved organic matter Fluorescence property Molecular composition Source

Steady-state and transient investigation of a small pressurized water reactor AcPR50S for different ATFs based on Bamboo-c code

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Nuclear Science and Techniques 2025年第1期36卷 192-206页

作者： Kun Zhuang Ying-Zhen wang Li-Na Deng Yong-Zhan wang Wen Shang Si-Peng wang Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Small modular reactors have received widespread attention owing to their inherent safety,low investment,and *** pressurized water reactors(SPWRs)have become important candidates for SMRs owing to their high technological *** the Fukushima accident,research on accident-tolerant fuels(ATFs),which are more resistant to serious accidents than conventional fuels,has gradually *** study analyzes the neutronics and thermal hydraulics of an SPWR(AcPR50S)for different ATFs,BeO+UO_(2)−Sic,BeO+UO_(2)−FecrAl,U_(3)Si_(2)−Sic,and U_(3)Si_(2)−FecrAl,based on a PWR fuel management code,the Bamboo-c deterministic *** the steady state,the burnup calculations,reactivity coefficients,power and temperature distributions,and control rod reactivity worth were *** transients of the control rod ejection accident for the two control rods with the maximum and minimum reactivity worth were *** results showed that 5%B-10 enrichment in the wet annular burnable absorbers assembly can effectively reduce the initial reactivity and end-of-life reactivity *** BeO+UO2−Sic core exhibited superior neutronic characteristics in terms of burnup and negative temperature reactivity compared with the other three cases owing to the strong moderation ability of BeO+UO_(2)and low neutron absorption of ***,the U_(3)Si_(2)core had a marginally better power-flattening effect than BeO+UO_(2),and the differential worth of each control rod group was similar between different *** the transient of a control rod ejection,the changes in the fuel temperature,coolant temperature,and coolant density were *** maximum difference was less than 10℃ for the fuel temperature and 2℃ for the coolant temperature.

关键词： AcPR50S Small pressurized water reactor ATF Steady Transient

Assessment of the dietary amino acid profiles and the relative biomarkers for amino acid balance in the low-protein diets for broiler chickens

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Journal of Animal Science and Biotechnology 2025年第1期16卷 238-266页

作者： Bin wang Xiaodan Zhang Yongfa Liu Mingkun Gao Mi wang Yuan wang Xinzhi wang Yuming Guo State Key Laboratory of Animal Nutrition and Feeding College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Shenyang Boeing Feed company Shenyang 110141China

Background Research on low-protein-level diets has indicated that even though the profiles of essential amino acids(EAAs)follow the recommendation for a normal-protein-level diet,broilers fed low-protein diets failed to achieve pro-ductive performance compared to those fed normal ***,it is imperative to reassess the optimum profile of EAAs in low-protein diets and establish a new ideal pattern for amino acid ***,identifying novel sensitive biomarkers for assessing amino acid balance will greatly facilitate the development of amino acid nutrition and application *** this study,12 dietary treatments[con(+),con(-),L&A(-),L&A(+),M&c(-),M&c(+),BcAA(-),BcAA(+),Thr(-),Thr(+),Trp(-)and Trp(+)]were established by combining different EAAs including lysine and argi-nine,methionine and cysteine,branched-chain amino acid(BcAA),threonine,and tryptophan to observe the growth and development of the broiler chickens fed with low-protein-level *** on the biochemical parameters and untargeted metabolomic analysis of animals subjected to different treatments,biomarkers associated with opti-mal and suboptimal amino acid balance were *** Growth performance,carcass characteristics,hepatic enzyme activity,serum biochemical parameters,and breast muscle mRNA expression differed significantly between male and female broilers under different dietary amino acid *** broilers exhibited higher sensitivity to the adjustment of amino acid patterns than female *** the low-protein diet,the dietary concentrations of lysine,arginine,and tryptophan,but not of methionine,cystine,or threonine,needed to be ***,further research on individual BcAA is *** untar-geted metabolomic analysis,con(+)was selected as a normal diet(NP)while con(-)represented a low-protein diet(LP).L&A(+)denotes a low-protein amino acid balanced diet(LPAB)and Thr(+)represents a low-protein amino acid imbalance diet(LPAI).The metaboli

关键词： Amino acid balance Biomarkers Essential amino acid Low-protein diet Metabolomics