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Ni–P coating on AZ31 magnesium alloy and its crystallization

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Rare Metals 2013年第5期32卷 465-468页

作者： Chun-mei Wang Jian-qing Wang Bing Zhang Run-Bing Niu jin-Ku Yu qin jing State Key Laboratory of Metastable Materials Science and Technology Yanshan University North China Institute of Aerospace Engineering

Amorphous Ni-P coating was plated on AZ31 magnesium alloy via the electroless plating technique, and the plated alloy was subsequently annealed. X-ray dif- fraction （XRD）, scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, and differential scanning calorimetry （DSC） were used to characterize the coating. The results show that the hardness of the coating is much higher than that of bare magnesium alloy, which further increases after crystallization. The electrochemical polarization and salt spray tests show that the coating exhibits a much higher corrosion resistance than that of the bare magnesium alloy. Moreover, the crystallized coating still exhibits a much stronger corrosion resistance than that of the bare magnesium alloy, although its corrosion resistance is lower than that of the as-plated one.

关键词： Ni-P coating Magnesium alloy Crystallization Corrosion resistance

Coordinating an Extended Warranty Supply Chain under Increasing,Constant and Decreasing Product Failure Rates

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Journal of Systems Science and Systems Engineering 2020年第5期29卷 609-628页

作者： Yuwen Chen jin qin Tongdan jin Yating Chen School of Management University of Science and Technology of ChinaHefei 230026China Department of Information Systems City University of Hong KongKowloon 999077Hong KongChina Ingram School of Engineering Texas State UniversitySan Marcos TX78666USA

A product typically exhibits three different failure rates across its lifetime:increasing,decreasing,or *** paper studies how the characteristics of failure rate impact the supply chain coordination for an extended warranty program involving a manufacturer and a retailer.A two-stage Stackelberg game is utilized to model the interaction between these two *** extended warranty channel structures are compared depending on whether the manufacturer or the retailer offers the warranty *** analysis shows that the failure rate trend during the warranty period has different effects on the coordination of the service supply *** a product has an increasing or constant failure rate,the optimal length of extended warranty offered by the retailer is longer than that of the manufacturer,while the optimal length is shorter for a product with a decreasing failure *** a product during the warranty coverage has an increasing or constant failure rate,a longer extended warranty period will motivate customers to buy the product without the warranty,whereas more customers will buy both the product and the warranty if the product experiences a decreasing failure *** is concluded that,if the manufacturer and the retailer incur the same warranty service cost,the total profit in the supply chain is higher when the manufacturer offers the extended *** the game participants'perspective,the one which sells the extended warranty will obtain more profit.

关键词： Supply chain coordination extended warranty failure rate warranty policy game theory

丹酚酸B调控脂质代谢改善非酒精性脂肪肝实验研究

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中国药理学通报 2025年第1期41卷 107-115页

作者：张佳健郭梦茹梅金玉陈明安徽医科大学基础医学院药理学教研室安徽合肥230032 安徽医科大学第二附属医院耳鼻喉科安徽合肥230601

目的探讨丹酚酸B(SalB)可能通过调控Lcn2改善非酒精性脂肪肝的作用。方法体内实验,8周龄♂C57BL/6J小鼠用普通维持饲料喂养,作为对照组,8周龄ApoE-/-小鼠用高脂饲料喂养,随机分为模型组和SalB组。在饲养8周后,SalB组小鼠用SalB灌胃,低... 详细信息

目的探讨丹酚酸B(SalB)可能通过调控Lcn2改善非酒精性脂肪肝的作用。方法体内实验,8周龄♂C57BL/6J小鼠用普通维持饲料喂养,作为对照组,8周龄ApoE-/-小鼠用高脂饲料喂养,随机分为模型组和SalB组。在饲养8周后,SalB组小鼠用SalB灌胃,低剂量为15 mg·kg^(-1)·d^(-1),高剂量为30 mg·kg^(-1)·d^(-1),对照组和模型组用等剂量生理盐水灌胃。肝脏转录组测序结果揭示模型组和SalB组的差异表达基因,HE染色、油红O染色观察肝组织的病理变化,试剂盒检测血清和肝组织的脂质、氧化应激和炎症指标,RT-qPCR检测Lcn2、SREBP-1C以及脂质合成相关酶的mRNA水平。体外实验,用棕榈酸(PA)诱导L02和LX-2细胞24 h建立NAFLD模型,用SalB(30μmol·L^(-1))和PA(0.2 mmol·L^(-1))共孵育检测SalB体外改善NAFLD的情况。试剂盒检测L02细胞TC、TG的含量,细胞油红O染色试剂盒检测L02细胞的脂质积累,RT-qPCR检测LX-2细胞Lcn2、SREBP-1C以及脂质合成相关酶基因的mRNA水平。结果模型组血清、肝脏的生化指标异常,肝组织脂质、炎症和氧化应激水平升高,出现大面积脂肪空泡和大量的脂质沉积,PA诱导的L02细胞也出现大量的脂质积累,在SalB干预后均有明显改善。转录组测序结果表明SalB可以调控肝脏脂质代谢和炎症。肝脏和LX-2细胞mRNA水平显示模型组Lcn2、SREBP-1C以及脂质合成相关酶基因表达明显上调,SalB干预后均能降低这些基因的表达。结论丹酚酸B可以明显改善非酒精性脂肪肝,其机制可能是通过下调Lcn2、SREBP-1C和脂质合成酶的表达。

关键词： SalB 非酒精性脂肪肝脂质代谢 Lcn2 SREBP-1C 脂质合成相关酶

Conservation Laws of Differential Equations in Finance

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Communications in Theoretical Physics 2005年第6X期44卷 967-968页

作者： qin Mao-Chang mei Feng-Xiang SHANG mei School of Science Chongqing Technology and Business University Chongqing 400067 China School of Science Beijing Institute of Technology Beijing 100081 China

Conservation laws of some differential equations in fiance are studied in this paper. This method does not involve the use or existence of a variational principle. As an alternative, linearize the given equation and find adjoint equation of the linearized equation, the conservation laws can be constructed directly from the symmetries and adjoint symmetries of the associated linearized equation and its adjoint equation.

关键词： conservation law adjoint equation finance

How high can fracture porosity become in the ultra-deep subsurface?

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Geoscience Frontiers 2023年第5期14卷 233-240页

作者： jin Lai Fei Zhao mei Zhang Tianyu Bai Yuyue Huang Dong Li Guiwen Wang Ziqiang qin State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)102249China Department of Petroleum Engineering University of WyomingLaramieWY 82071USA

Knowledge of how high can fracture porosity become in the ultra-deep burial conditions is important but remains *** aperture and porosity are measured using X-ray computed tomography(CT)at atmospheric pressure and then calculated by image *** attention is paid to how high fracture porosity can become in ultra-deep(>6000 m)settings,and which situations will result in high fracture *** situ stress magnitudes,which can be calculated using well logs,control fracture performances,and dissolution along fracture improve fracture porosity at ultra-deep burial *** horizontal stress difference(Dr45 MPa),a high degree of dissolution along the fracture dramatically increases fracture *** will result in the vuggy fracture planes and improve fracture porosity up to 2.0%.The results provide insights into the detection,characterization,and modeling of subsurface fractures.

关键词： Fracture porosity Image log Ultra-deep In-situ stress Dissolution

Response to temperature stress of reactive oxygen species scavenging enzymes in the cross-tolerance of barley seed germination

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第12期11卷 965-972页

作者： Yu-qin mei Song-quan SONG Institute of Botany Chinese Academy of Sciences Beijing 100093 China

A number of studies have shown the existence of cross-tolerance in plants, but the physiological mechanism is poorly understood. In this study, we used the germination of barley seeds as a system to investigate the cross-tolerance of low-temperature pretreatment to high-temperature stress and the possible involvement of reactive oxygen species （ROS） scavenging enzymes in the cross-tolerance. After pretreatment at 0 ℃ for different periods of time, barley seeds were germinated at 35 ℃, and the content of malondialdehyde （MDA） and the activities of ROS scavenging enzymes were measured by a spectrophotometer analysis. The results showed that barley seed germinated very poorly at 35 ℃, and this inhibitive effect could be overcome by pretreatment at 0 ℃. The MDA content varied, depending on the temperature at which seeds germinated, while barley seeds pretreated at 0 ℃ did not change the MDA content. Compared with seeds germinated directly at 35 ℃, the seeds pretreated first at 0 ℃ and then germinated at 35 ℃ had markedly increased activities of superoxide dismutase （SOD）, ascorbate peroxidase （APX）, catalase （CAT）, and glutathione reductase （GR）. The SOD and APX activities of seeds germinated at 35 ℃ after 0 ℃-pretreatment were even substantially higher than those at 25 ℃, and GR activity was similar to that at 25 ℃, at which the highest germination performance of barley seeds was achieved. These results indicate that low-temperature pretreatment can markedly increase the tolerance of barley seed to high temperature during germination, this being related to the increase in ROS scavenging enzyme activity. This may provide a new method for increasing seed germination under stress environments, and may be an excellent model system for the study of cross-tolerance.

关键词： Barley seed Cross-tolerance Germination/growth Reactive oxygen species (ROS) scavenging enzyme,Pretreatment at low temperature Temperature stress

A novel ophthalmic viscosurgical devicefree phakic intraocular lens implantation makes myopic surgery safer

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Eye and Vision 2020年第1期7卷 171-179页

作者： An-Peng Pan Li-jin Wen Xu Shao Kai-jing Zhou qin-mei Wang Jia Qu A-Yong Yu The Eye Hospital of Wenzhou Medical University 270 Xueyuan West Road

Purpose:To assess the efficacy and safety of a novel ophthalmic viscosurgical device-free(OVD-free)method for posterior chamber phakic intraocular lens(PIOL)implantation in myopic ***:In this retrospective cohort study,the medical records of myopic eyes that underwent PIOL(Implantable Collamer Lens,ICL)implantation for myopia correction at the Eye Hospital of Wenzhou Medical University between May 2015 and March 2017 were reviewed.A total of 49 eyes with complete data that met follow up requirements(2 h,1 day,1 week,3 months postoperatively)were *** on the surgical techniques used,the eyes were divided into the OVD-free method group and the standard method *** clinical data,including intraocular pressure(IOP),corrected distance visual acuity(CDVA)and spherical equivalent(SE),at each follow-up were collected for *** cell loss and complications were also ***:Twenty-one eyes received the standard method,and 28 eyes received the OVD-free method.A rise in IOP>22 mmHg at 2 h was noted in 14 eyes(66.7%)in the standard group and none(0%)in the OVD-free group(p<0.001).The rise in IOP from baseline was significantly higher at 2 h in the standard group(10.5±5.2 mmHg vs.2.2±3.3 mmHg,difference:8.3,95%CI 5.8 to 10.8;p<0.001).There was a significant difference in the time course of LogMAR CDVA changes between the two groups(p=0.047).The LogMAR CDVA was significantly better in the OVD-free method group compared to the standard group at 1 day(−0.076,95%CI−0.134 to−0.018;p=0.012),1 week(−0.071,95%CI−0.135 to−0.007;p=0.03),but not at 3 months(−0.046,95%CI−0.107 to 0.015;p=0.134).There was no significant difference in the time course of SE changes between the two groups(p=0.471;p=0.705).In the OVD-free group,mean endothelial cell loss was 4.6%at 3 months(2522±281 vs.2407±226 cells/mm^(2),difference:-115,95%CI−295 to 65;p=0.187).No complications were reported in both groups except for the early IOP elevation in the standard

关键词： Phakic intraocular lens implantation Ophthalmic viscosurgical device-free Intraocular pressure Complications

Mg doping and native N vacancy effect on electronic and transport properties of AlN nanowires

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Science China(Technological Sciences) 2015年第5期58卷 832-841页

作者： qin mei SHANG Yan WANG Xiao ZHANG GuiLing Innovative Research Team of Green Chemical Technology in University of Heilongjiang Province College of Chemical and Environmental Engineering Harbin University of Science and Technology

The effects of Mg doping(MgAl) and native N vacancy(VN) on the electronic structures and transport properties of Al N nanowire(Al NNW) were theoretically investigated by using density functional theory. Either the MgAl defect or the VN defect prefers to be formed on the Al NNW surfaces. Both MgAl and VN defects could increase the conductivity owing to introducing a defect band inside the band gap of Al N and split the Al N band gap into two subgaps. The defect concentration has little influence on the magnitude of the subgaps. The MgAl serves as a shallow acceptor rendering the nanowire a p-type conductor. The VN introduces a deep donor state enabling the nanowire an n-type conductor. The MgAl systems exhibit higher conductivity than the VN ones owing to the narrow subgaps of MgAl systems. The conductivity is roughly proportional to the defect concentration in the MgAl and VN defect systems. When the MgAl and VN coexist, the hole state of the MgAl defect and the electron state of the VN defect will compensate each other and their coupling state appears just above the valence-band maximum leading to a little decrease of the band gap compared with the pure Al NNW, which is unfavorable for the enhancing of the conductivity.

关键词： doping enabling rendering compensate introducing valence magnitude defects narrow nanotubes

Quantum entropy based tabu search algorithm for energy saving in SDWN

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Science China(Information Sciences) 2017年第4期60卷 85-100页

作者： Chaowei WANG Wuyang mei Xiangying qin Weidong WANG School of Electronic Engineering Beijing University of Posts and Telecommunications

The energy consumption of the base station(BS) accounts for great proportion of the total wireless access network(WAN). Switching off the selected spare BSs with few network request would save a large amount of energy. It is difficult to deploy a BS energy saving strategy in existing network architecture due to the tightly coupled network devices. Therefore, we adopt the software defined wireless networks(SDWN) structure which is an sample of the wireless software defined networks(SDN). Then a novel quantum entropy based tabu search algorithm(QETS) is proposed to choose which BS to switch off, and it increases the search range and guarantee the convergence speed. The energy saving strategy can find the optimal solution with higher probabilities and can be deployed in centralized controller as a software. Theoretical analysis and simulation results show the QETS algorithm's gain over the greedy algorithm and quantum inspired tabu search algorithm(QTS) in terms of convergence.

关键词： energy saving SDN SDWN quantum entropy quantum inspired tabu search algorithm