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Characterization and degradation of β-Sn particles in thermal aged Pb-rich solder joint for low-temperature co-fired ceramic(LTCC) applications

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Rare Metals 2024年第10期43卷 5346-5361页

作者： Jin-Hong liu Zhe Zhu Qiang-Qiang Nie jun-fu liu Peng He Shu-Ye Zhang State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Anhui Key Laboratory of Microsystem East China Research Institute of Microelectronics School of Materials Science and Engineering Hefei University of Technology

High-lead solder joints are still playing an indispensable role in military and space ***, in-depth characterization of high-lead solder joints and the underlying degradation mechanisms remain unexplored. This research first performed aging tests on Sn10Pb90 solder joints, the shear strength at room and elevated temperatures gradually reduced, and the resistance increased. Here, a two-layered Ni–Sn intermetallic compound(IMC) structure was identified using transmission electron microscopy(TEM), which could be attributed to the change of Sn content in the solder. Moreover, the internal annealing twin of a Sn particle was discovered,which could be attributed to creeping induced by thermal expansion coefficient(CTE) difference between Sn and *** analysis of partial and whole annealing twins was conducted through high-resolution TEM(HRTEM).Finally, four degradation mechanisms were *** of the IMC layer would result in increased brittleness and resistivity. For particle coarsening, apart from diminishing the ductility and toughness of the solder joint, it would also accelerate the creeping rate by weakening the phase boundary strength. Regarding voids and cracks induced by phase boundary sliding, wedgeshaped cracking and pore-shaped cracking were discovered and their formation was analyzed. Most importantly, the consumption of Sn resulted in a depletion of wettable layer,leading to the formation of Pb streams and isolated IMC islands, also known as the spalling and delamination of IMCs. Pb diffusion followed a spiral path, which was mutually influenced by orientation misfit and concentration gradient. A technique to prevent cracking was *** research is expected to provide significant technical references for high-lead solder joints.

关键词： Aging Degradation mechanisms High-lead solder joints Properties TEM characterization

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Small Interfering RNA Targeting MDR1 Inhibits Ovarian Cancer Growth and Increases Efficacy of Chemotherapy in vivo

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Chinese Journal of Cancer Research 2009年第4期21卷 318-324页

作者： fu-jun liu Guo-lan Gao Kai-jia Tu Li-qun Yu jun Gao Department of Obstetrics and Gynecology the First Affiliated Hospital Nanchang University Nanchang 330006 China Department of Obstetrics and Gynecology the Second Affiliated Hospital Nanchang University Nanchang 330006 China.

Objective： To further validate a knockdown approach for circumventing the multidrug resistance gene （MDR1）, we used small interfering RNA（siRNA） targeting MDR1 gene to inhibit the expression of MDR1 gene and P-glycoprotein（P-gp） in vivo. Methods： Ascite tumor xenografts were established by implanting human ovarian carcinoma cells SKOV3/AR intraperitoneally into the nude mice. The mice were randomized into the following three treatment groups with each group six mice respectively： Taxol, Taxol with lipofectamine and Taxol with siRNA/MDR1- lipofectamine intraperitoneal injection. The tumor growth rate and the ascite growth rate of mice were investigated. The expressions of MDR1 gene and P-gp in mice were determined by reverse transcription-polymerase chain reaction（RT-PCR） and immunohistochemistry respctively. Results： The growth of tumors and ascites in mice treated with Taxol and siRNA/MDR1- lipofectamine was significantly inhibited compared with those in mice of other groups. After 28 days＇ treatment, the average tumor weight and ascite volume decreased by 43.6% and 29.7% in the group treated with Taxol and siRNA/MDRl-lipofectamine compared with these treated with Taxol alone （P〈0.001）. The expressions of MDR1 gene and P-gp in the group treated with Taxol and siRNA/MDRl-lipofectamine were also decreased compared with those in the group treated with Taxol alone （P〈0.001）. Conclusion： Small interfering RNA targeting-MDR1 can effectively and specifically suppress the expression of MDRl（P-glycoprotein） and inhibit ovarian cancer growth in vivo.

关键词： RNA interference siRNA MDR1 gene Ovarian cancer Nude mice

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Switched-capacitor Based Seven-level Boost Inverter with a Reduced Number of Devices

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 381-391页

作者： Weijie Lin jun Zeng Bo fu Zhixing Yan junfeng liu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China WISDRI Engineering&Research Incorporation Limited Wuhan 430074China Department of Energy Aalborg UniversityAalborg 9220Denmark School of Automation Science and Engineering South China University of TechnologyGuangzhou 510641China

The conventional multilevel inverters(MLIs)have the disadvantages of numerous devices,incapacity of boost,unbalance for capacitor’s voltage,high complexity for control,and *** by this issue,a seven-level boost inverter(7LBI)based on a switched capacitor is presented for singlephase applications in this *** proposed 7LBI using only seven transistors can achieve seven output levels,1.5 voltage gain,and natural balance of capacitors’voltages without sensors or other auxiliary methods,which illustrates its suitability for the applications of renewable energy *** configuration of topology and operating principles are illustrated in *** natural balance of capacitors and capacitance calculations are deduced as ***,the comparative study is conducted for different types of *** results illustrate the merits of the proposed 7LBI with respect to reduced devices,lower voltage stress,and less power ***,a simulation for the proposed 7LBI with PWM modulation is realized based on the theoretical analysis;an experimental prototype is also implemented,verifying multilevel output,boost ability,natural balance for switched capacitors,and performance of transient response.

关键词： Multilevel inverters voltage gain natural balance renewable energy generation reduced number of elements

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Comparison of gene expression of the oncogenic Wnt/β-catenin signaling pathway components in the mouse and human epididymis

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Asian Journal of Andrology 2015年第6期17卷 1006-1011,I0011页

作者： Kai Wang Ning Li Ching-Hei Yeung Trevor G Cooper Xue-Xia liu Juan liu Wen-Ting Wang Yan Li Hui Shi fu-jun liu School of Agriculture Ludong University Yantai Shandong China Central Laboratory Yantai Yuhuangding Hospital Yantai Shandong China College of Life Science Yantai University Yantai Shandong China

β-catenin is an integral part of the Wnt signaling pathway and has been linked to tumorigenesis and multiple developmental processes. The high β-catenin expression with low tumor incidence in the human epididymis is thus intriguing. In the present study, the β-catenin gene and protein was found to be highly expressed in the murine caput epididymidis, and the protein mainly localized along the lateral plasma membranes of adjacent epithelial cells throughout both human and mouse epididymides. furthermore, the adult mouse epididymis was found to express almost all the Wnt/β-catenin signaling pathway genes that were determined previously by our group in the human organ. Despite the differences in epididymal structure, the similar location of β-catenin and the high concordance of this pathway＇s components＇ gene expression in both the adult human and mouse epididymides make the mouse a suitable animal model for studying the anti-tumor mechanism of the epididymis. In addition, both the mRNA and protein expression of β-catenin shared a similar spatial expression as the mRNA of Rosl, a proto-oncogene and a key developmental regulator of the initial segment of the mouse epididymis. The observations on the parallel temporal expression of β-catenin and Rosl during postnatal development raise the possibility that the canonical Writ signaling pathway has an additional role in the postnatal development of mouse epididymis.

关键词： epididymis postnatal development tumorigenesis Wnt/β-catenin pathway β-catenin

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Preparation and Rheological Characterization of Long Chain Branching Polyglycolide

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Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： Wei-Lin liu Ming-fu Lyu Heng-Yuan Zhang Jian-Ye liu Shi-jun Zhang Beijing University of Chemical Technology Beijing 100029China SINOPEC(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.

关键词： Polyglycolide(PGA) Long chain branching(LCB) Rheology

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Effects of combination therapy with atenolol and amlodipine on blood pressure control and stroke prevention in stroke-prone spontaneously hypertensive rats

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Acta Pharmacologica Sinica 2007年第11期28卷 1755-1760页

作者： Gang LING,Ai-jun liu,fu-ming SHEN,Guo-jun CAI,Jian-guo liu,Ding-feng SU~2Department of Pharmacology,School of Pharmacy Second Military Medical University,Shanghai 200433,China Department of Pharmacology School of Pharmacy Second Military Medical University Shanghai China

Aim:To test the effects of atenolol and amlodipine,either alone or in combination,on blood pressure,blood pressure variability (BPV),baroreflex sensitivity (BRS),and the prevalence of stroke in stroke-prone spontaneously hypertensive rats(SHR-SP).Methods:In the first set of the study,24 8-month-old,female SHR-SPrats were randomly divided into 3 *** pressure,heart period,and BRSwere determined before and after the intragastric administration of atenolol (10mg/kg) and amlodipine (1.0 mg/kg),either alone or in *** the secondset of the study,40 male and 40 female rats were randomly assigned to 1 of thefollowing 4 groups:control,atenolol (10 mg·kg-1·d-1),amlodipine (1.0 mg·kg-1·d-1),and both (10 male and 10 female in each group).The stroke incident and survivaltime were ***:Atenolol and amlodipine,either alone or incombination,significantly decreased blood pressure,with the exception of theamlodipine-induced effect on diastolic blood ***,only the com-bination treatment significantly decreased the BPV levels for the same *** q-values calculated by the probability sum analysis were 1.17 and 2.67 forsystolic and diastolic blood pressure,respectively,and were 2.48 and 2.10 forsystolic and diastolic BPV,respectively,following *** drugexhibited any significant effect on *** and amlodipine,either alone orin combination,significantly increased the lifespan of SHR-SP,with the best ef-fect elicited by the combination ***:A significant synergismexists between atenolol and amlodipine in lowering and stabilizing blood pressurein *** therapy may be an optimal strategy for the prevention ofstroke in hypertension.

关键词： stroke hypertension stroke-prone spontaneouslyhypertensive rats atenolol amlodipine blood pressure blood pressure variability

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Deep Guided Attention Network for Joint Denoising and Demosaicing in Real Image

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Chinese Journal of Electronics 2024年第1期33卷 303-312页

作者： Tao ZHANG Ying fu jun ZHANG School of Computer Science and Technology Beijing Institute of Technology Advanced Reasearch Institute of Multidisciplinary Science Beijing Institute of Technology

Denoising(DN) and demosaicing(DM) are the first crucial stages in the image signal processing pipeline. Recently, researches pay more attention to solve DN and DM in a joint manner, which is an extremely undetermined inverse problem. Existing deep learning methods learn the desired prior on synthetic dataset, which limits the generalization of learned network to the real world data. Moreover, existing methods mainly focus on the raw data property of high green information sampling rate for DM, but occasionally exploit the high intensity and signalto-noise(SNR) of green channel. In this work, a deep guided attention network(DGAN) is presented for real image joint DN and DM(JDD), which considers both high SNR and high sampling rate of green information for DN and DM, respectively. To ease the training and fully exploit the data property of green channel, we first train DN and DM sub-networks sequentially and then learn them jointly, which can alleviate the error accumulation. Besides, in order to support the real image JDD, we collect paired raw clean RGB and noisy mosaic images to conduct a realistic dataset. The experimental results on real JDD dataset show the presented approach performs better than the state-of-the-art methods, in terms of both quantitative metrics and qualitative visualization.

关键词： Training Visualization Inverse problems Green products Noise reduction Pipelines Signal processing

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Magnetic properties and magnetocaloric effects in Eu(Ti,Nb,Mn)O_(3) perovskites

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Journal of Rare Earths 2024年第8期42卷 1560-1567,I0006页

作者： junfeng Wang Huicai Xie Quanyi liu Zhihong Hao Zhaojun Mo Qi fu Xinqiang Gao jun Shen Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou341000China School of Rare Earth and New Materials Engineering Gannan University of Science and TechnologyGanzhou341000China Department of Energy and Power Engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China

In perovskite EuTiO_(3),the magnetic characteristics and magnetocaloric effect(MCE) can be flexibly regulated by converting the magnetism from antiferromagnetic to *** the present work,a series of Eu(Ti,Nb,Mn)O_(3) compounds,abbreviated as ETNMO for convenience of description,was fabricated and their crystallography,magnetism together with cryogenic magnetocaloric effects were systematically *** crystallographic results demonstrate the cubic perovskite structure for all the compounds,with the space group of *** magnetic phase transitions are observed in these second-order phase transition(SOPT) *** joint substitution of elements Mn and Nb can considerably manipulate the magnetic phase transition process and magnetocaloric performance of the ETNMO *** the Mn content increases,gradually widened-ΔS_(M)-T curves are obtained,and two peaks with a broad shoulder are observed in the-ΔS_(M)-T curves for Δμ_(0)H≤0-1 *** a field change of 0-5 T,the values of maximum magnetic entropy change(-ΔS_(M)^(max)) and refrigeration capacity(RC) are evaluated to be 34.7 J/(kg·K) and 364.9 J/kg for EuTi_(0.8625)Nb_(0.0625)Mn_(0.075)O_(3), 27.8 J/(kg·K) and367.6 J/kg for EuTi_(0.8375)Nb_(0.0625)Mn_(0.1)O_(3),23.2 J/(kg·K) and 369.2 J/kg for EuTi_(0.8125)Nb_(0.0625)Mn_(0.125)O_(3),17.1 J/(kg·K) and 357.6 J/kg for EuTi_(0.7875)Nb_(0.0625)Mn_(0.15)O_(3),*** co nsiderable MCE parameters make the ETNMO compounds potential candidates for cryogenic magnetic refrigeration.

关键词： ETNMO perovskites Cryogenic refrigeration Magnetic phase transition Magnetocaloric effect Rare earths

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Hydrogel-Assisted Electrokinetics for High-Resolution and Non-invasive Flow Monitoring in Microfluidic Chips

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Chinese Journal of Chemistry 2024年第6期42卷 571-577页

作者： Na Zhao Yanni Ma Zehua Yu jun Huang Xiangqian fu Tao Qiu Kang liu MOE Key Laboratory of Hydraulic Machinery Transients School of Power and Mechanical EngineeringWuhan UniversityWuhanHubei430072 China Department of Urology Renmin Hospital of Wuhan UniversityWuhanHubei430072 China Department of Organ Transplantation Renmin Hospital of Wuhan UniversityWuhanHubei430072 China

Convenient non-invasive flow monitoring would facilitate the operation and control in microfluidic chips,but is challenging due to the small space of microchannels and complex operation required in traditional optical *** this work,we propose a novel non-invasive strategy to probe microfluidic flows via streaming potential *** sealing one side of the microchannel with a piece of hydrogel film,streaming potential inside the channel can be clearly detected by electrodes at outer surface of the hydrogel due to ion diffusion in the *** is detected without sensors contacting with the internal ***,the electrodes shape like a tiny probe,which can move around mapping the flow distribution in a chip with the spatial resolution of 1 mm and flow rate detection limit of 3μL·min–*** inside the channels can also be detected,due to the fluctuation of streaming voltage when gas-liquid interface flows through the electrode,showing an easy and potential way for multi-functional flow monitoring in microfluidic chips.

关键词： Microfluidics Hydrogels Electrokinetics Flow monitoring Non-invasive Sensor Charge transport

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Combined blasting for protection of gob-side roadway with thick and hard roof

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3165-3180页

作者： Qiang fu jun Yang Yubing Gao Changjiang Li Hongxu Song Yuxuan liu Xing Wu State Key Laboratory for Tunnel Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China

The deformation control of surrounding rock in gobside roadway with thick and hard roof poses a significant challenge to the safety and efficiency of coal *** address this issue,a novel approach combining directional and non-directional blasting techniques,known as combined blasting,was *** study focuses on the experimental investigation of the proposed method in the 122108 working face in Caojiatan Coal Mine as the engineering *** initial phase of the study involves physical model experiments to reveal the underlying mechanisms of combined blasting for protecting gob-side roadway with thick and hard *** results demonstrate that this approach effectively accelerates the collapse of thick and hard roofs,enhances the fragmentation and expansion coefficient of gangue,facilitates the filling of the goaf with gangue,and provides support to the overlying strata,thus reducing the subsidence of the overlying strata above the ***,the method involves cutting the main roof into shorter beams to decrease the stress and disrupt stress transmission *** numerical simulations were conducted to corroborate the findings of the physical model experiments,thus validating the accuracy of the experimental ***,field engineering experiments were performed,affirming the efficacy of the combined blasting method in mitigating the deformation of surrounding rock and achieving the desired protection of the gob-side roadway.

关键词： Thick and hard roof Surrounding rock control Combined blasting Fragmentation and expansion support stress relief

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