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科技型中小微企业技术创新能力决定因素研究——基于战略性新兴产业上市企业数据

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科技进步与对策 2013年第18期30卷 88-92页

作者：段一群张立凡李佩南京信息工程大学中国制造业发展研究院江苏南京210044 南京邮电大学经济与管理学院江苏南京210046

面向战略性新兴产业内中小企业(含中型、小型、微型3种类型),对其技术创新能力的决定因素进行独创性研究。基于所择定的114家上市企业数据,运用探索性因子分析和聚类分析方法,研究影响其技术创新能力的决定因素,即创新投入水平、管理层... 详细信息

面向战略性新兴产业内中小企业(含中型、小型、微型3种类型),对其技术创新能力的决定因素进行独创性研究。基于所择定的114家上市企业数据,运用探索性因子分析和聚类分析方法,研究影响其技术创新能力的决定因素,即创新投入水平、管理层技术知识水平、内在创新驱动程度、创新资源和机会开发的努力程度、研发产出水平,并在此基础上构建出当前适用的五维度技术创新能力评价指标体系。最后,有针对性地提出政策建议。

关键词：战略性新兴产业科技型中小微企业技术创新能力

用于实现医学图像对比度增强的密文域可逆信息隐藏算法

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上海理工大学学报 2024年第1期46卷 95-102页

作者：李安周亮张建青陈立范周艳丽王宏杰孔平上海理工大学健康科学与工程学院上海200093 上海健康医学院协同科研中心上海201318 上海健康医学院医学影像学院上海201318 上海健康医学院文理教学部上海201318

针对现有密文域医学图像可逆信息隐藏算法存在解密图像视觉质量较低的问题,提出了一种基于差值直方图平移的密文域可逆信息隐藏算法。首先,发送方采用具有同态密文比较性质的加密算法对原始医学图像进行加密,从而保证医学图像的隐私内... 详细信息

针对现有密文域医学图像可逆信息隐藏算法存在解密图像视觉质量较低的问题,提出了一种基于差值直方图平移的密文域可逆信息隐藏算法。首先,发送方采用具有同态密文比较性质的加密算法对原始医学图像进行加密,从而保证医学图像的隐私内容不被泄露。然后,嵌入方利用同态性质对接收到的密文图像计算差值直方图,并通过平移差值直方图在密文图像中嵌入信息。为了获得较大的嵌入率,嵌入方可对密文图像进行多轮次信息嵌入。最后,接收方根据拥有的密钥种类对接收到的含有嵌入信息的密文图像进行信息提取、图像解密和图像恢复。实验结果表明,本文算法提升了解密医学图像的视觉质量,同时具有较高的嵌入率和安全性。

关键词：可逆信息隐藏医学图像直方图平移同态加密图像对比度增强

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祛白颗粒对氢醌诱导白癜风小鼠的疗效

医药导报 2019年第12期38卷 1596-1600页

作者：杨爱霞徐蕾张力凡武汉市第一医院药学部武汉430022 湖北中医药大学药学院武汉430065

目的观察祛白颗粒对氢醌诱导的白癜风小鼠的治疗效果。方法用2.5%氢醌乳膏涂抹小鼠背部皮肤持续20 d造模,得到白癜风小鼠后给予不同剂量祛白颗粒灌胃40 d。实验结束时评分计算治疗有效率;取背部皮肤采用苏木精-伊红(HE)染色法观察,统计... 详细信息

目的观察祛白颗粒对氢醌诱导的白癜风小鼠的治疗效果。方法用2.5%氢醌乳膏涂抹小鼠背部皮肤持续20 d造模,得到白癜风小鼠后给予不同剂量祛白颗粒灌胃40 d。实验结束时评分计算治疗有效率;取背部皮肤采用苏木精-伊红(HE)染色法观察,统计小鼠皮肤含黑色素毛囊数、基底层黑素细胞数和含黑素细胞表皮细胞数;小鼠眼眶取血,使用酶联免疫吸附法(ELISA)检测小鼠血清中酪氨酸酶(TYR)、胆碱酯酶(ChE)、单胺氧化酶(MAO)含量。结果白癜风小鼠经过小、中、大剂量祛白颗粒治疗后,复色评价有效率结果分别为44.4%,66.7%,81.2%(P<0.01);病理切片实验发现,与模型对照组比较,治疗后小鼠皮肤中的黑色素毛囊数、基底层黑素细胞、含黑素颗粒表皮细胞均有增加,其中中、大剂量组小鼠增加数量差异有统计学意义(P<0.05);小鼠血清检验结果显示,祛白颗粒能明显上调TYR(P<0.01)及下调MAO、ChE水平(P<0.01)。结论祛白颗粒治疗小鼠白癜风有一定的疗效,其作用机制可能与调节血清中MAO、TYR的含量有关。

关键词：祛白颗粒白癜风动物造模治疗效果

Novel Au nanoparticles-inlaid titanium paper for PEM water electrolysis with enhanced interfacial electrical conductivity

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International Journal of Minerals,Metallurgy and Materials 2022年第5期29卷 1090-1098页

作者： Yue Liu Shaobo Huang Shanlong Peng Heng zhang lifan Wang Xindong Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Department of Energy Storage Science and Engineering School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China School of Physics and Engineering Henan University of Science and TechnologyLuoyang 471023China

Proton-exchange membrane water electrolysis(PEM WE)is a particularly promising technology for renewable hydrogen ***,the excessive passivation of the gas diffusion layer(GDL)will seriously affect the high surface-contact resistance and result in energy ***,a mechanism for improving the conductivity and interface stability of the GDL is an urgent *** this work,we have prepared a hydrophilic and corrosion resistant conductive composite protective *** polydopamine(PDA)film on the Ti surface,which was obtained via the solution oxidation method,ensured that neither micropores nor pinholes existed in the final hybrid ***-situ reduced gold nanoparticles(AuNPs)improved the conductivity to achieve the desired interfacial contact resistance and further enhanced the corrosion *** surface composition of the treated samples was investigated using scanning electron microscopy(SEM),transmis-sion electron microscopy(TEM),X-ray diffraction(XRD),and Fourier transform infrared spectroscopy(FTIR).The results indicated that the optimized reaction conditions included a pH value of 3 of HAuCl_(4) solution with PDA deposition(48 h)on papers and revealed the lowest con-tact resistance(0.5 mΩ·cm^(2))and corrosion resistance(0.001μA·cm^(−2))in a 0.5 M H_(2)SO_(4)+2 ppm F−solution(1.7 V ***)among all the modified specimens,where RHE represents reversible hydrogen *** findings indicated that the Au-PDA coating is very appropriate for the modification of Ti GDLs in PEM WE systems.

关键词： water electrolysis proton-exchange membrane hydrogen energy titanium paper diffusion layer Au nanoparticles inlaid titanium gold–polydopamine nanocomposite

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用电路噪声测量玻尔兹曼常量和电子电荷

物理实验 2023年第3期43卷 43-49页

作者：宋冰睿张立帆齐潇骏刘佳睿张翀玮王中平张增明中国科学技术大学少年班学院安徽合肥230026 中国科学技术大学严济慈物理科技英才班安徽合肥230026 中国科学技术大学物理学院物理实验教学中心安徽合肥230026

设计并搭建热噪声和散粒噪声测试电路系统,利用锁相放大器,从极强的背景噪声中提取微弱待测电信号,输入参考信号实现频谱搬移测量法,测定了玻尔兹曼常量k和电子电荷e.该实验能够加深学生对电路噪声特性的理解,掌握锁相放大器技术和微弱... 详细信息

设计并搭建热噪声和散粒噪声测试电路系统,利用锁相放大器,从极强的背景噪声中提取微弱待测电信号,输入参考信号实现频谱搬移测量法,测定了玻尔兹曼常量k和电子电荷e.该实验能够加深学生对电路噪声特性的理解,掌握锁相放大器技术和微弱信号测量方法.

关键词：玻尔兹曼常量电子电荷频谱搬移测量法热噪声散粒噪声锁相放大器参考信号

A critical review on nickel-based cathodes in rechargeable batteries

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International Journal of Minerals,Metallurgy and Materials 2022年第5期29卷 925-941页

作者： lifan Wang Jingyue Wang Leiying Wang Mingjun zhang Rui Wang Chun Zhan State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China

The 3d transition-metal nickel(Ni)-based cathodes have long been widely used in rechargeable batteries for over 100 years,from Ni-based alkaline rechargeable batteries,such as nickel-cadmium(Ni-Cd)and nickel-metal hydride(Ni-MH)batteries,to the Ni-rich cathode featured in lithium-ion batteries(LIBs).Ni-based alkaline batteries were first invented in the 1900s,and the well-developed Ni-MH batteries were used on a large scale in Toyota Prius vehicles in the *** the same time,however,Sony Corporation commercialized the first LIBs in *** temporally fading as LiCoO_(2) dominated the cathode in LIBs,nickel oxide-based cathodes eventually found their way back to the mainstreaming battery *** uniqueness of Ni in batteries is that it helps to deliver high energy density and great storage capacity at a low *** review mainly provides a comprehensive overview of the key role of Ni-based cathodes in rechargeable *** presenting the physical and chemical properties of the 3d transition-metal Ni,which make it an optimal cationic redox center in the cathode of batteries,we introduce the structure,reaction mechanism,and modification of nickel hydroxide electrode in Ni-Cd and Ni-MH rechargeable *** then move on to the Ni-based layered oxide cathode in LIBs,with a focus on the structure,issues,and challenges of layered oxides,LiNiO_(2),and LiNi_(1−x−y)Co_(x)Mn_(y)O_(2).The role of Ni in the electrochemical performance and thermal stability of the Ni-rich cathode is *** bridging the“old”Ni-based batteries and the“modern”Ni-rich cathode in the LIBs,this review is committed to providing insights into the Ni-based electrochemistry and material design,which have been under research and development for over 100 *** overview would shed new light on the development of advanced Ni-containing batteries with high energy density and long cycle life.

关键词： nickel-based alkaline batteries nickel hydroxide electrodes lithium-ion battery Ni-rich layered oxide cathodes

Determination of Permissible Levels of Added Airflow Resistance for Aircraft Oxygen Equipment in Pilots

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Journal of Medical Colleges of PLA 1988年第1期 23-30页

作者：马瑞山倪鹤鹦张立藩 Department of Aviation Physiology Fourth Military Medical University Xi’an

The effects of added airflow resistance（0.3-3 kPa·L.（-1）·s）on therespiratory flow rate and mask cavity pressure as well as the subject’s perceptionwere investigated in 114 pilots under light physical activities(250kg·m·min-).A correlation and stepwise regression analysis was made to reveal the objectivephysiological indexes which could reflect the effects of the added resistance, and aprobit analysis was made to confirm the permissible levels for added *** results suggest that both mask cavity pressure swing（P） and extra respiratorywork per unit ventilation(W.L-1)could be used as the objective physiological,,indexes for respiratory discomfort,and the former may be more *** Pdoes not exceed 0.60kPa or if W L-1does not exceed 0.047 kg·m L-1,90％ ofthe subjects will feel no respiratory discomfort;if P does not exceed 0.77kPa orW·L-1not exceed 0.061 kg·m·L-1,90％ may only feel less than mediumrespiratory *** problem concerning the revision of the currentstandards of respiratory resistance of aircraft oxygen equipment is discussed inthis paper.

关键词： aircraft oxygen equipment mask cavity pressure external respiratory work respiratory sensation permissible levels for added airflow resistance

Data-driven modeling method with reverse process

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International Journal of Modeling, Simulation, and Scientific Computing 2022年第2期13卷 16-29页

作者： Guodong Yi lifan Yi Zaizhao zhang Chuihui Li State Key Laboratory of Fluid Power&Mechatronic SystemsZhejiang University Hangzhou 310027P.R.China Xiangyang Boya Precision Industrial Equipment Co. Ltd.China

The factors that affect the performance of the equipment are numerous and complicated,which makes it difficult to establish a performance calculation *** paper puts forward a data-driven modeling method with reverse process for this *** on the partial least squares(PLS)algorithm and the gray relational analysis(GRA)method,the analysis method of the performance related factors,the extraction method of characteristic variables,and the performance modeling method are *** related factors of the energy consumption of an industrial steam turbine are analyzed,and an energy consumption calculation model is established,and the effectiveness of the above-mentioned modeling methods is verified with sample data,which provides a basis for the energy-saving optimization of the steam turbine.

关键词： Data-driven reverse process PLS GRA

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南桑北植后生理结构和防冻机制的改变研究

现代农业研究 2022年第4期28卷 84-86页

作者：孔庆慧郭琼瑶佟铭洋王泽张力凡通化师范学院生命科学学院吉林通化134000

本试验选用东北地区的移植红果桑树树枝、叶柄和本地桑树进行对比对照实验,判断不同浓度脱落酸对移植桑的叶片脱落效果.通过本实验发现以脱落酸:清水为1:20的浓度配比整体效果最优,能解决移栽到东北地区的红果桑树异常生理现象,同时经... 详细信息

本试验选用东北地区的移植红果桑树树枝、叶柄和本地桑树进行对比对照实验,判断不同浓度脱落酸对移植桑的叶片脱落效果.通过本实验发现以脱落酸:清水为1:20的浓度配比整体效果最优,能解决移栽到东北地区的红果桑树异常生理现象,同时经济实惠且省时省力,以期开创桑树东北地区栽培技术体系的新思路。

关键词：移植桑石蜡切片脱落酸