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Journal of Energy and Power Engineering 2013年第3期7卷 583-588页

作者： wan-rone liou Mary Loralie E.Bulasa Yi-Cheng Lu Wei-Chih Chen Shi-Xian wang Department of Electrical Engineering National Taipei University Taipei 23741 Taiwan

This research describes an integrated multi-channel high accuracy current control LED （light emitting diode） driver with low dropout regulator implemented in a 0.35μm TSMC 2P4M CMOS process. With the new trend of backlighting applications for mobile electronics and portable devices requiring a smaller size, lower cost, lesser noise and accurate current control LED driver, it came up with the idea of integrating more than one design features within a single chip. The analysis of using a capacitor-less low dropout regulator to power the constant current source has been explored, with the implementation of wide range battery voltage of 3 V to 5 V. Possible load current variations were introduced and verified to output a fixed voltage of 2.8 V. A regulated cascode current mirror structure forms the multi-channel configuration string of LED＇s; the design ensures a current matching of less than 1% error and achieves a high accuracy current control of less than 1% error, regardless of the LED＇s forward voltage variation. Moreover, for high end portable device with multimedia applications, dimming frequency can be set to 10 MHz. In addition, a switching output is a better approach for managing LED＇s contrast and brightness adjustment as well as maximizing power consumption, ensuring longer life for driving string of LEDs.

关键词： LED driver low dropout regulator multi-channel dimming control.

A Dual-Mode Step-up DC/DC Converter IC with Current-Limiting and EMI Reduction Techniques

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Journal of Electronic Science and Technology of China 2008年第3期6卷 279-283页

作者： wan-rone liou Ping-Hsing Chen Marynelle L. Z. Rosales Yeh Chun-Ting Kuo Mei-Ling Yeh the Graduate Institute of Electrical Engineering National Taipei University San Shia Taipei 23741 Taiwan China the Department of Electrical Engineering National Taiwan Ocean University Keelung Taiwan China

This paper presents a novel dual-mode step-up （boost） DC/DC converter. Pulse-frequency modulation （PFM） is used to improve the efficiency at light load. This converter can operate between pulse-width modulation （PWM） and pulse-frequency modulation. The converter will operate in PFM mode at light load and in PWM mode at heavy load. The maximum conversion efficiency of this converter is 96%. The conversion efficiency is greatly improved when load current is below 100 mA. Additionally, a soft-start circuit and a variable-sawtooth frequency circuit are proposed in this paper. The former is used to avoid the large switching current at the start up of the converter and the latter is utilized to reduce the EMI of the converter.

关键词： Boost converter dual-mode converter integrated power management pulse-frequency modulation (PFM) pulse-width modulation (PWM)

InGaN multiple quantum well based light-emitting diodes with indium composition gradient InGaN quantum barriers

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Optoelectronics Letters 2024年第2期20卷 89-93页

作者： SANG Xien XU Yuan YIN Mengshuang wanG Fang liou Juin J LIU Yuhuai National Center for International Joint Research of Electronic Materials and Systems International Joint-Laboratory of Electronic Materials and Systems of Henan ProvinceSchool of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China Institute of Intelligence Sensing Zhengzhou UniversityZhengzhou 450001China Research Institute of Industrial Technology Co. Ltd.Zhengzhou UniversityZhengzhou 450001China Zhengzhou Way Do Electronics Co. Ltd.Zhengzhou 450001China School of Electrical and Information Engineering North Minzu UniversityYinchuan 750001China1

To improve the internal quantum efficiency(IQE)and light output power of In Ga N light-emitting diodes(LEDs),we proposed an In-composition gradient increase and decrease In Ga N quantum barrier *** analysis of its P-I graph,carrier concentration,and energy band diagram,the results showed that when the current was 100 m A,the In-composition gradient decrease quantum barrier(QB)structure could effectively suppress electron leakage while improving hole injection efficiency,resulting in an increase in carrier concentration in the active region and an improvement in the effective recombination rate in the quantum well(QW).As a result,the IQE and output power of the LED were effectively improved.

关键词： diodes quantum gradient

Accelerated intermetallic phase amorphization in a Mg-based high-entropy alloy powder

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Journal of Magnesium and Alloys 2024年第5期12卷 1792-1798页

作者： Prince Sharma Purvam Mehulkumar Gandhi Kerri-Lee Chintersingh Mirko Schoenitz Edward L.Dreizin Sz-Chian liou Ganesh Balasubramanian Institute for Functional Materials&Devices Lehigh UniversityBethlehemPA 18015USA Center of Materials for Advanced Energetics New Jersey Institute of TechnologyNewarkNJ 07102USA

We describe a novel mechanism for the synthesis of a stable high-entropy alloy powder from an otherwise immiscible Mg-Ti rich metallic mixture by employing high-energy mechanical *** presented methodology expedites the synthesis of amorphous alloy powder by strategically injecting entropic disorder through the inclusion of multi-principal elements in the alloy *** from first principles and materials theory corroborate the results from microscopic characterizations that reveal a transition of the amorphous phase from a precursor intermetallic *** transformation,characterized by the emergence of antisite disorder,lattice expansion,and the presence of nanograin boundaries,signifies a departure from the precursor intermetallic ***,this phase transformation is accelerated by the presence of multiple principal elements that induce severe lattice distortion and a higher configurational *** atomic size mismatch of the dissimilar elements present in the alloy produces a stable amorphous phase that resists reverting to an ordered lattice even on annealing.

关键词： High-entropy alloy High-energy milling Antisite disorder Amorphous Intermetallic

Insights and implications of sexual dimorphism in osteoporosis

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Bone Research 2024年第1期12卷 20-49页

作者： Yuan-Yuan Zhang Na Xie Xiao-Dong Sun Edouard C.Nice Yih-Cherng liou Canhua Huang Huili Zhu Zhisen Shen Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China West China School of Basic Medical Sciences&Forensic Medicine Sichuan UniversityChengdu 610041China Department of Biochemistry and Molecular Biology Monash UniversityClaytonVIC 3800Australia Department of Biological Sciences Faculty of ScienceNational University of SingaporeSingapore 117543Republic of Singapore Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China Hospitaland West China School of Basic Medical Sciences&Forensic MedicineSichuan UniversityChengdu 610041China Key Laboratory of Birth Defects and Related Diseases of Women and Children of Ministry of Education Department of Reproductive MedicineWest China Second University Hospital of Sichuan UniversityChengduChina Department of Otorhinolaryngology and Head and Neck Surgery The Affiliated Lihuili HospitalNingbo University315040 NingboZhejiangChina

Osteoporosis,a metabolic bone disease characterized by low bone mineral density and deterioration of bone microarchitecture,has led to a high risk of fatal osteoporotic fractures *** evidence has revealed that sexual dimorphism is a notable feature of osteoporosis,with sex-specific differences in epidemiology and ***,females are more susceptible than males to osteoporosis,while males are more prone to disability or death from the *** date,sex chromosome abnormalities and steroid hormones have been proven to contribute greatly to sexual dimorphism in osteoporosis by regulating the functions of bone *** the sex-specific differences in osteoporosis and its related complications is essential for improving treatment strategies tailored to women and *** literature review focuses on the mechanisms underlying sexual dimorphism in osteoporosis,mainly in a population of aging patients,chronic glucocorticoid administration,and ***,we highlight the implications of sexual dimorphism for developing therapeutics and preventive strategies and screening approaches tailored to women and ***,the challenges in translating bench research to bedside treatments and future directions to overcome these obstacles will be discussed.

关键词： osteoporosis epidemiology overcome

平行沟槽织构对TB6钛合金表面润湿性、摩擦学性能和耐腐蚀性的改善

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稀有金属材料与工程 2024年第3期53卷 617-624页

作者：郭嘉梁王芳刘俊杰刘玉怀郑州大学电气与信息工程学院电子材料与系统国际联合研究中心河南省电子材料与系统国际联合实验室河南郑州450001 郑州大学智能传感研究院河南郑州450001 郑州大学产业技术研究院有限公司河南郑州450001 郑州唯独电子科技有限公司河南郑州450001 北方民族大学电气与信息工程学院宁夏银川750001

提出了一种快速制备具有超疏水性、耐磨性和耐腐蚀性的Ti-10V-2Fe-3Al(TB6)钛合金表面的方法。通过纳秒激光器对抛光的钛合金进行精确烧蚀,构筑了具有平行微沟槽阵列特征的织构表面。随后,利用紫外线灯照射和十八烷基三氯硅烷溶液浸渍... 详细信息

提出了一种快速制备具有超疏水性、耐磨性和耐腐蚀性的Ti-10V-2Fe-3Al(TB6)钛合金表面的方法。通过纳秒激光器对抛光的钛合金进行精确烧蚀,构筑了具有平行微沟槽阵列特征的织构表面。随后,利用紫外线灯照射和十八烷基三氯硅烷溶液浸渍进行化学改性,进一步增强了表面的疏水性。从表面形态和化学组分的角度分析了微沟槽间隔对织构表面润湿性的影响。结果表明,在干滑动、水润滑和油润滑条件下,所制备的超疏水表面相较于原始亲水表面,平均摩擦系数分别降低了34%、56%和59%。此外,分析了相关摩擦系数变化的机理。通过动电位极化测试验证,所制备的超疏水表面展现出优异的耐腐蚀性,为钛合金基体提供了有效的长期保护。

关键词：激光织构钛合金超疏水性摩擦学性能耐腐蚀性

Parameterization of the Absorption of the H_(2)O Continuum,CO_(2),O_(2),and Other Trace Gases in the Fu-liou Solar Radiation Program

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Advances in Atmospheric Sciences 2005年第4期22卷 545-558页

作者：张凤曾庆存 Y.GU K.N.liou InstituteofAtmosphericPhysics ChineseAcademyofSciencesBeijing100029 DepartmentofAtmosphericandOceanicSciences UniversityofCaliforniaLosAngelesCalifornia90095

The absorption properties of the water vapor continuum and a number of weak bands for H2O, O2, CO2, CO, N2O, CH4, and O3 in the solar spectrum are incorporated into the Fu-liou radiation parameterization program by using the correlated k-distribution method (CKD) for the sorting of absorption lines. The overlap absorption of the H2O lines and the H2O continuum (2500-14500 cm-1) are treated by taking the two gases as a single-mixture gas in transmittance calculations. Furthermore, in order to optimize the computation efforts, CO2 and CH4 in the spectral region 2850-5250 cm-1 are taken as a new single-mixture gas as well. For overlap involving other absorption lines in the Fu-liou spectral bands, the authors adopt the multiplication rule for transmittance computations under which the absorption spectra for two gases are assumed to be uncorrelated. Compared to the line-by-line (LBL) computation, it is shown that the errors in fluxes introduced by these two approaches within the context of the CKD method are small and less than 0.48% for the H2O line and continuum in the 2500-14500 cm-1 solar spectral region, -1% for H2O (line)+H2O (continuum)+CO2+CH4 in the spectral region 2850-5250 cm-1, and -1.5% for H2O (line)+H2O (continuum)+O2 in the 7700-14500 cm-1 spectral region. Analysis also demonstrates that the multiplication rule over a spectral interval as wide as 6800 cm-1 can produce acceptable errors with a maximum percentage value of about 2% in reference to the LBL calculation. Addition of the preceding gases increases the absorption of solar radiation under all sky conditions. For clear sky, the increase in instantaneous solar absorption is about 9%-13% (~12 W m^2) among which the H2O continuum produces the largest increase, while the contributions from O2 and CO2 rank second and third, respectively. In cloudy sky, the addition of absorption amounts to about 6-9 W m-2. The new, improved program with the incorporation of the preceding gases produces a smaller solar a

关键词： non-gray gas absorption correlated k-distribution method Fu-liou code

Nanohybrid TiO_2/carbon black sensor for NO_2 gas

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China Particuology 2007年第3期5卷 225-229页

作者： Wei-Jen liou Department of Materials Engineering Tatung University Taipei 104 Taiwan China

A nanohybrid sensor of nanosized TiO2-coated carbon black particles, prepared by sol-gel technology for the detection of NO2 gas, has been developed. The response of the electric resistance of the hybrid sensor to NO2 concentration is investigated, showing that the sensitivity of the hybrid sensor is raised as certain ratio of the TiO2 content in the sensor. Easy and cheap to fabricate, the hybrid TiO2/carbon black promises to be a practical sensor for detecting NO2 gas. 2007 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V.

关键词： Carbon black TiO2 Gas sensing Hybrid

Characterization of gold/PMMA hybrid nanomaterials synthesized by hard X-ray synchrotron radiation

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Particuology 2010年第3期8卷 234-239页

作者： Hueywen liou Weijen liou Hongming Lin Yeukuang Hwu Wenchang Chen Department of Materials Engineering Tatung University No. 7-1 DeHui St. Institute of Physics Academia Sinica Nankang Department of Chemical and Materials Engineering National Yunlin University of Science and Technology

In this study, new types of hybrid gold poly（methyl methacrylate）（PMMA） nanomaterials are synthesized. Both PMMA spheres coated with gold nanoparticles and gold nanoparticles coated with PMMA can be synthesized using different ratios of HAuCl4 and MMA precursors, by exposing the mixtures to hard X-ray synchrotron radiation without the use of a reducing agent. According to the photochemical mechanism, gold nanoparticles will precipitate from a solution of HAuCl4 on exposure to synchrotron radiation, followed by the synthesis of PMMA by the polymerization of MMA monomers. These reactions can result in the formation of two different types of new hybrid nanomaterials. When a 1：1 volume ratio of HAuCI4 to MMA is used, we obtain PMMA spheres coated with gold nanoparticles. When a 10：1 ratio of HAuCl4 and MMA is used, we obtain gold nanoparticles coated with PMMA. The hybrid gold/PMMA nanostructures are characterized by transmission electron microscopy, elemental analysis, dynamic-light scattering analysis, gel permeation chromatography and Raman spectroscopy. The hybrid nanomaterials have potential application in the fields of biosensors and drug delivery.

关键词： Nanoparticle Gold Poly(methyl methacrylate) Hard X-ray