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基于NodeMCU和Home Assistant的智能家居控制系统
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作者 杨骏 梁念渝 王凯 《通讯世界》 2024年第8期124-126,共3页
为了提高家居生活的舒适性和便利性,开发了一套智能家居控制系统。该系统采用节点微控制单元(NodeMCU)作为基础硬件,负责收集传感器数据并操控相关执行器件。同时,该系统利用消息队列遥测传输协议(MQTT)和WiˉFi技术构建数据传输链路。... 为了提高家居生活的舒适性和便利性,开发了一套智能家居控制系统。该系统采用节点微控制单元(NodeMCU)作为基础硬件,负责收集传感器数据并操控相关执行器件。同时,该系统利用消息队列遥测传输协议(MQTT)和WiˉFi技术构建数据传输链路。此外,该系统利用开源的Home Assistant系统建立了后台服务端,以实现数据的图形化展示。用户可通过安卓移动设备实时监控家居环境状况,并对智能设备实施控制。该系统经过严格测试,表现稳定,显著提高了家居环境的智能化程度。 展开更多
关键词 NodeMCU Home assistant 智能家居
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Research on Multi-modal In-Vehicle Intelligent Personal Assistant Design
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作者 WANG Jia-rou TANG Cheng-xin SHUAI Liang-ying 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期136-146,共11页
Intelligent personal assistants play a pivotal role in in-vehicle systems,significantly enhancing life efficiency,driving safety,and decision-making support.In this study,the multi-modal design elements of intelligent... Intelligent personal assistants play a pivotal role in in-vehicle systems,significantly enhancing life efficiency,driving safety,and decision-making support.In this study,the multi-modal design elements of intelligent personal assistants within the context of visual,auditory,and somatosensory interactions with drivers were discussed.Their impact on the driver’s psychological state through various modes such as visual imagery,voice interaction,and gesture interaction were explored.The study also introduced innovative designs for in-vehicle intelligent personal assistants,incorporating design principles such as driver-centricity,prioritizing passenger safety,and utilizing timely feedback as a criterion.Additionally,the study employed design methods like driver behavior research and driving situation analysis to enhance the emotional connection between drivers and their vehicles,ultimately improving driver satisfaction and trust. 展开更多
关键词 Intelligent personal assistants Multi-modal design User psychology In-vehicle interaction Voice interaction Emotional design
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High performance micromachining of sapphire by laser induced plasma assisted ablation(LIPAA)using GHz burst mode femtosecond pulses
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作者 Kotaro Obata Shota Kawabata +2 位作者 Yasutaka Hanada Godai Miyaji Koji Sugioka 《Opto-Electronic Science》 2024年第6期20-29,共10页
GHz burst-mode femtosecond(fs)laser,which emits a series of pulse trains with extremely short intervals of several hundred picoseconds,provides distinct characteristics in materials processing as compared with the con... GHz burst-mode femtosecond(fs)laser,which emits a series of pulse trains with extremely short intervals of several hundred picoseconds,provides distinct characteristics in materials processing as compared with the conventional irradiation scheme of fs laser(single-pulse mode).In this paper,we take advantage of the moderate pulse interval of 205 ps(4.88 GHz)in the burst pulse for high-quality and high-efficiency micromachining of single crystalline sapphire by laser induced plasma assisted ablation(LIPAA).Specifically,the preceding pulses in the burst generate plasma by ablation of copper placed behind the sapphire substrate,which interacts with the subsequent pulses to induce ablation at the rear surface of sapphire substrates.As a result,not only the ablation quality but also the ablation efficiency and the fabrication resolution are greatly improved compared to the other schemes including single-pulse mode fs laser direct ablation,single-pulse mode fs-LIPAA,and nanosecond-LIPAA. 展开更多
关键词 femtosecond laser GHz burst mode ablation LIPAA laser induced plasma assisted ablation SAPPHIRE
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Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesized Transition Metal Nanostructures
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作者 Victor J. Law 《American Journal of Analytical Chemistry》 CAS 2024年第6期201-218,共18页
This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy... This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage. 展开更多
关键词 microwave-assisted Synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature Green Chemistry
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不同方法对根管内氢氧化钙去除效果的micro-CT评价 被引量:1
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作者 伍甜甜 韩艳彦 汪轶 《上海口腔医学》 CAS 2024年第3期225-228,共4页
目的:应用显微CT(micro-computed tomography,micro-CT)建立磨牙根管模型,评价不同方法对氢氧化钙的清除效率。方法:收集2023年10月—2024年2月口腔综合科门诊拔除的11颗磨牙(24个根管),按照标准根管治疗流程,镍钛器械预备完成后,在根... 目的:应用显微CT(micro-computed tomography,micro-CT)建立磨牙根管模型,评价不同方法对氢氧化钙的清除效率。方法:收集2023年10月—2024年2月口腔综合科门诊拔除的11颗磨牙(24个根管),按照标准根管治疗流程,镍钛器械预备完成后,在根管内置入氢氧化钙,1周后,根据不同冲洗方法将样本随机分为侧方开口注射器组、超声荡洗组(EMS组)和声波震荡组(EDDY组)等3组(n=8)。冲洗前后使用micro-CT重建根管系统并使用不同颜色标记独立根管,计算各个根管氢氧化钙体积,比较各组氢氧化钙清除率。采用SPSS 19.0软件包对数据进行统计学分析。结果:3种方法均无法完全去净根管内氢氧化钙。使用次氯酸钠作为冲洗液时,超声荡洗和声波震荡清除效果优于侧方开口冲洗器(P<0.05);超声荡洗和声波震荡去除氢氧化钙效率相当,差异无统计学意义(P>0.05);氢氧化钙残留部位集中于根尖区。结论:Micro-CT能较为高效地重建磨牙根管模型,可用于评价氢氧化钙去除效果。超声荡洗组和声波震荡组清除氢氧化钙效率相当,优于侧方开口注射器组。 展开更多
关键词 micro-CT 氢氧化钙 超声荡洗 声波震荡 EMS EDDY
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基于LabVIEW和Vision Assistant的车牌识别系统设计 被引量:2
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作者 许卫洪 《无线互联科技》 2023年第7期58-60,共3页
文章提出了一种基于LabVIEW和Vision Assistant的车牌识别方案。系统使用Vision Assistant的颜色阈值、高级形态学及光学字符识别等函数,实现了对车牌图像的预处理和车牌区域定位以及车牌字符分割、字符训练和识别,使用LabVIEW程序完成... 文章提出了一种基于LabVIEW和Vision Assistant的车牌识别方案。系统使用Vision Assistant的颜色阈值、高级形态学及光学字符识别等函数,实现了对车牌图像的预处理和车牌区域定位以及车牌字符分割、字符训练和识别,使用LabVIEW程序完成车牌的显示。使用数百张车牌图像对该系统进行验证,结果证实该方案是可行的,系统是可靠的,可以快速、准确定位和识别车牌。 展开更多
关键词 车牌识别 视觉助手 车牌定位 字符分割与识别
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Micro LED车灯投影光学系统设计与优化 被引量:1
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作者 李香兰 金霞 +7 位作者 吕金光 郑凯丰 陈宇鹏 赵百轩 赵莹泽 秦余欣 王惟彪 梁静秋 《中国光学(中英文)》 EI CAS CSCD 北大核心 2024年第1期89-99,共11页
本文提出了一种基于Micro LED阵列的车灯投影方案,设计了以像素尺寸为80μm×80μm的200×150白光Micro LED阵列作为显示光源,视场角为16°×34°的车灯投影光学系统,并对物面倾斜角度和光学系统结构进行了优化。此... 本文提出了一种基于Micro LED阵列的车灯投影方案,设计了以像素尺寸为80μm×80μm的200×150白光Micro LED阵列作为显示光源,视场角为16°×34°的车灯投影光学系统,并对物面倾斜角度和光学系统结构进行了优化。此外,分别采用反向畸变处理方法和像素灰度调制方法用以解决车灯投影图像的梯形畸变和照度均匀性问题,并搭建了投影实验平台,对图像校正方法进行了验证。实验结果表明:校正后图像梯形畸变系数p1,p2分别从0.0932和0.3680下降至0.0835和0.0373,像面照度均匀性从83.2%提高到93.2%。本文通过对基于Micro LED的倾斜投影车灯光学系统进行优化设计及采用图像校正方法,实现了高光效、低畸变的车灯投影。 展开更多
关键词 车灯投影光学系统 光学设计 micro LED 照度均匀性 梯形畸变
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光子晶体Micro LED微显示阵列加工及光学特性分析 被引量:1
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作者 孟媛 肖秧 +4 位作者 冯晓雨 何龙振 张鹏喆 宁平凡 刘宏伟 《半导体技术》 CAS 北大核心 2024年第8期719-725,共7页
Micro LED器件具有高亮度、低功耗和高可靠性等优点,但Micro LED显示像素巨量转移和光提取效率低的问题为其应用带来挑战。开发了具有高转移效率和出光效率的单片64×64 Micro LED微显示阵列,提出了倒装型GaN基单片Micro LED微显示... Micro LED器件具有高亮度、低功耗和高可靠性等优点,但Micro LED显示像素巨量转移和光提取效率低的问题为其应用带来挑战。开发了具有高转移效率和出光效率的单片64×64 Micro LED微显示阵列,提出了倒装型GaN基单片Micro LED微显示阵列芯片和Si基驱动电路的设计方法及集成工艺。通过时域有限差分(FDTD)方法对Micro LED微显示阵列光学特性进行了建模分析,设计了一种提高Micro LED微显示阵列出光效率的光提取结构。结合仿真结果,开发了一种在Micro LED蓝宝石衬底表面制备光子晶体结构的聚焦离子束(FIB)微纳加工工艺,并进行了器件加工。测试结果表明,蓝宝石衬底上加工的光子晶体结构可以提高Micro LED器件的表面出光效率,光功率平均值提升了16.36%,对Micro LED微显示阵列加工及微显示像素光提取问题具有借鉴意义。 展开更多
关键词 micro LED 微显示阵列 光子晶体结构 聚焦离子束(FIB) 出光效率
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基于Micro CT的铜导线短路熔痕孔洞特征分析
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作者 陈克 郭宇航 +3 位作者 邓松华 王轩磊 张亮亮 张斌 《消防科学与技术》 CAS 北大核心 2024年第4期566-571,共6页
导线短路是造成电气火灾的重要原因之一。现行国家标准中将导线短路熔痕分为起火前发生的一次短路熔痕和起火后造成的二次短路熔痕,然而现行国家标准中的鉴定仅停留在定性判断的阶段。火灾现场铜导线短路熔痕特征的量化分析研究是国内... 导线短路是造成电气火灾的重要原因之一。现行国家标准中将导线短路熔痕分为起火前发生的一次短路熔痕和起火后造成的二次短路熔痕,然而现行国家标准中的鉴定仅停留在定性判断的阶段。火灾现场铜导线短路熔痕特征的量化分析研究是国内外研究人员主要关注的重点。本文应用Micro CT技术对铜导线短路熔痕进行断层扫描检测并重构铜导线短路熔痕的3D图像数据,在此基础上统计、归纳、总结铜导线短路熔痕内部孔洞形态及分布等孔洞特征。研究表明,Micro CT能够全面采集铜导线短路熔痕的整体形态和内部孔洞特征,一次短路熔痕与二次短路熔痕内部孔洞半径、表面积、紧密度的特征数据存在差别,可为短路熔痕定性和定量分析判据研究提供新的理论依据。 展开更多
关键词 micro CT 短路熔痕 孔洞特征 火灾物证鉴定
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Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel 被引量:2
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作者 Qian Li Zi-Jie Lin +3 位作者 Liu Yang Yue Wang Yue Li Wei-Hua Cai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1275-1289,共15页
The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the... The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 mm.Numerical simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow features.The results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were analyzed.In calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So heat transfer deterioration should be taken seriously in the design and safe operation of vaporizer PCHE. The study of this work clarified the local heat transfer and flow feature of supercritical methane in microchannel and contributed to the deep understanding of supercritical methane flow of the vaporization process in PCHE. 展开更多
关键词 Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling micro segment analysis
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Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid 被引量:2
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作者 Yusuf Suleiman Dambatta Changhe Li +8 位作者 Mohd Sayuti Ahmed A D Sarhan Min Yang Benkai Li Anxue Chu Mingzheng Liu Yanbin Zhang Zafar Said Zongming Zhou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期115-136,共22页
Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL ... Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL system is affirmed to exhibit an excellent machining performance,and it is highly economical.The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL system.Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids.This work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)ceramic.The effect different grinding modes and lubrication systems during the grinding operation was also analyzed.Different concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower oils.The quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface integrity.It was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication systems.Additionally,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%respectively.Finally,regression analysis was used to obtain an optimum parameter combinations.The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics. 展开更多
关键词 Minimum quantity lubrication(MQL) Ultrasonic assisted grinding(UAG) Eco-friendly lubricants NANOFLUID GRINDING CERAMIC
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Micro-CT分析跟骨内骨小梁分布及结构特征 被引量:1
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作者 张凤珍 孙瑞芬 +4 位作者 李梓瑜 王星 李琨 李志军 张少杰 《中国组织工程研究》 CAS 北大核心 2024年第24期3885-3889,共5页
背景:跟骨位于足的后下部,受力较大。跟骨外形复杂且不规则,外周有较薄的皮质骨包绕,内部充满大量的骨小梁,探讨骨小梁的微观结构、走行及分布特征有助于提高对跟骨骨折的认识。目的:采用微计算机断层扫描仪(Micro-CT)扫描跟骨标本获得... 背景:跟骨位于足的后下部,受力较大。跟骨外形复杂且不规则,外周有较薄的皮质骨包绕,内部充满大量的骨小梁,探讨骨小梁的微观结构、走行及分布特征有助于提高对跟骨骨折的认识。目的:采用微计算机断层扫描仪(Micro-CT)扫描跟骨标本获得其影像资料,对其内部骨小梁结构进行分析,探讨跟骨内骨小梁的形态、分布及结构特征。方法:采用Micro-CT连续扫描干燥成人跟骨标本,扫描后获得影像图像,将其以DICOM格式存储。导入影像资料到Hiscan Analyzer软件,显示清晰完整的成人跟骨矢状面、冠状面、水平面的图像,逐层观察骨小梁的走行,依据骨小梁走行特点将跟骨矢状面分为6个部分,在以7 mm为标准的相同厚度下,每个部分选择1个49 mm2等面积的兴趣区,三维重建后获得跟骨及骨小梁的立体微观结构,二值化后运用软件计算感兴趣区域内骨小梁的体积分数、表面密度、骨小梁厚度、骨小梁间隙和骨小梁数量参数。结果与结论:①跟骨表面皮质层很薄,内部充满大量骨松质,在Gissane角的骨皮质明显增厚;②跟骨上部的骨小梁体积分数大于跟骨下部前端、中和三角区、跟骨下后部、跟骨结节部、跟骨底部,跟骨结节部的骨小梁体积分数大于跟骨下部前端、中和三角区、跟骨下后部、跟骨底部;跟骨结节部的骨小梁表面密度大于跟骨下部前端、中和三角区、跟骨底部,跟骨上部、跟骨下后部的骨小梁表面密度大于中和三角区;跟骨上部的骨小梁厚度大于跟骨结节部;中和三角区的骨小梁间隙大于跟骨上部、跟骨结节部;跟骨结节部的骨小梁数量大于中和三角区;③中和三角区主要分布杆状骨小梁,骨小梁表面密度最小、体积分数较小、骨小梁间隙最大;该部位骨质较疏松,受到高冲击力时抗压缩能力差,骨小梁最先发生断裂,是易发生骨折的部位。 展开更多
关键词 microCT 跟骨 骨小梁 形态特征 骨折
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Managements of Special Health Care Needs Patients from Dental Assistant Point
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作者 Abdullah M. G. Al Enazi Dalal Khalaf Al Enazi +3 位作者 Haya Nasser Al Duaida Ashwag Bander Al Bakheet Mashael Muteb Al Ghobain Abeer Salem Al Harbi 《International Journal of Clinical Medicine》 CAS 2023年第2期59-64,共6页
The main role of this article is to describe dental assistants and the dental department’s role in the dental delivery system for Special health care needs (SCHN) by creating a structure to educate the dental assisti... The main role of this article is to describe dental assistants and the dental department’s role in the dental delivery system for Special health care needs (SCHN) by creating a structure to educate the dental assisting profession and project factors that have a significant impact on the dental assistant. The dental assisting management of SCHN patient’s profession including dental Assistance general responsibilities, regulation credentialing, and education. The SCHN patient’s management creates a challenge in all area of the dental department. Handling patient with a SCHN is underexplored throughout the dental staff especially when there is not enough theoretical foundation, education and training to deal with this category of patients. SCHN patients are defined as individuals who have abnormal behavioral impairments, mental conditions or/and chronic disease or abnormal laboratory results. Thus, the aim of this article is to guide all dental assistance staff in the best dental management choice for SCHN patients. All health care teams are part of patient care in most medical settings. A work environment supportive ensures positive outcomes for patient care. This article was considered as those categories of patients required more care and special way to deal with, moreover language, age, gender and education level of the patient are also considered significant parries. Not Many studies were found to support the care of SCHN patients in dentistry department. Taking experience from other area help to design a system to handle the SCHN even if it requires hiring a Dentist who is specialized in that filed. 展开更多
关键词 Dental Management Dental assistant DENTIST Special Needs Special Health Care Need
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Advances in microfluidic-based DNA methylation analysis 被引量:1
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作者 Jiwen Li Tiechuan Li Xuexin Duan 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期116-134,共19页
DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation ... DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation studies to both clinical medicine and scientific research.Microflu-idic chips are excellent carriers for molecular analysis,and their use can provide improvements from multiple aspects.On-chip molecular analysis has received extensive attention owing to its advantages of portability,high throughput,low cost,and high efficiency.In recent years,the use of novel microfluidic chips for DNA methylation analysis has been widely reported and has shown obvious superiority to conventional methods.In this review,wefirst focus on DNA methylation and its applications.Then,we discuss advanced microfluidic-based methods for DNA methylation analysis and describe the great progress that has been made in recent years.Finally,we summarize the advantages that microfluidic technology brings to DNA methylation analysis and describe several challenges and perspectives for on-chip DNA methylation analysis.This review should help researchers improve their understanding and make progress in developing microfluidic-based methods for DNA methylation analysis. 展开更多
关键词 microfluidic chip DNA methylation analysis Molecular analysis High throughput Low cost
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高亮绿光氮化镓基Micro-LED微型显示器制备
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作者 张杰 王光华 +10 位作者 邓枫 杨文运 高思博 鲁朝宇 孟泽阳 高树雄 常诚 曹坤宇 马赛江 刘颖琪 王丽琼 《红外技术》 CSCD 北大核心 2024年第10期1186-1191,共6页
Micro-LED作为一种新型的显示技术,具有对比度高、响应快及寿命长等优点,已成为当前研究的热点。然而,尽管潜力巨大,Micro-LED技术的商业化之路仍面临诸多技术上的挑战与瓶颈。本文旨在探讨高亮绿光氮化镓基Micro-LED微型显示器的制备... Micro-LED作为一种新型的显示技术,具有对比度高、响应快及寿命长等优点,已成为当前研究的热点。然而,尽管潜力巨大,Micro-LED技术的商业化之路仍面临诸多技术上的挑战与瓶颈。本文旨在探讨高亮绿光氮化镓基Micro-LED微型显示器的制备过程及其相关技术。基于WVGA041全数字信号电路CMOS硅基驱动电路,制作了0.41 inch、分辨率为800×480的主动式单色绿光Micro-LED微型显示器。利用高精度倒装焊接技术实现了CMOS驱动电路与LED发光芯片的电气连接。结果表明,制备出LED显示芯片正常启亮电压为2.8V,EL光谱峰值波长524nm;在硅基CMOS电路驱动范围内,Micro-LED微型显示器在5V电压下,器件亮度为108000cd/m^(2)(最大亮度可达250000 cd/m^(2)),电流密度达到0.61A/cm^(2)时色坐标为(0.175,0.756)。当电流密度从0.3A/cm^(2)增加到1.3A/cm^(2)时,色坐标从(0.178,0.757)变化到(0.175,0.746),器件的色稳定性能够满足实际应用要求。 展开更多
关键词 micro-LED 微型显示器 高亮单色绿光发光二级管
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Micro RNAs与急性心肌梗死关系的研究进展
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作者 薛婷匀 闫贞蓉 +2 位作者 李广妹 赵佳叶 孙启玉 《承德医学院学报》 2024年第1期66-70,共5页
急性心肌梗死(acute myocardial infarction,AMI)是冠状动脉疾病最严重的表现,其引起的心肌组织损伤可促进心力衰竭的发展。尽管近些年由于生活方式的改变、治疗方式(如经皮冠状动脉介入治疗)的发展使AMI的预后得到了改善,但是AMI依旧... 急性心肌梗死(acute myocardial infarction,AMI)是冠状动脉疾病最严重的表现,其引起的心肌组织损伤可促进心力衰竭的发展。尽管近些年由于生活方式的改变、治疗方式(如经皮冠状动脉介入治疗)的发展使AMI的预后得到了改善,但是AMI依旧每年危害着全球700多万人的身心健康,AMI仍然是世界范围内高发病率和高死亡率的主要疾病之一[1]。微小RNA(micro RNAs,miRNAs)是在20世纪90年代被发现的,mi RNAs的研究已经迅速发展成为一个成熟而广阔的领域。mi RNAs存在于几乎所有类型的细胞和细胞的病理生理活动中,包括与心血管系统相关的细胞。本文将mi RNAs对AMI病理生理进程的影响进行综述,希望为临床治疗提供新思路。 展开更多
关键词 micro RNAs 急性心肌梗死 作用机制 预后
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基于量子点@有序介孔复合材料的Micro⁃LED色转换特性
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作者 陈晓钢 赵梦云 +6 位作者 蔡俊虎 李恭明 查楠 叶芸 徐胜 郭太良 陈恩果 《发光学报》 EI CAS CSCD 北大核心 2024年第1期59-68,共10页
量子点(Quantum dots)由于具有优异的光电特性,广泛应用于发光与显示、太阳能电池、光催化等领域,它的发现和合成获得了2023年诺贝尔化学奖。采用量子点色转换的Micro-LED全彩化显示技术无需巨量转移,有望实现大规模量产,然而,量子点在... 量子点(Quantum dots)由于具有优异的光电特性,广泛应用于发光与显示、太阳能电池、光催化等领域,它的发现和合成获得了2023年诺贝尔化学奖。采用量子点色转换的Micro-LED全彩化显示技术无需巨量转移,有望实现大规模量产,然而,量子点在高强度Micro-LED出光激发下的性能和寿命仍存在局限。基于此,本文研究了基于量子点@有序介孔(QDs@SBA-15)复合材料的Micro-LED色转换技术及其特性,有序介孔分子筛载体独特的孔道结构不仅能够有效提升Micro-LED色转换和光提取效率,且致密的有序介孔材料也一定程度上保障了量子点的稳定性。首先,通过时域有限差分方法(FDTD)建立了Micro-LED仿真模型,探究量子点粒径和有序介孔材料的孔径对光提取效率的影响;基于仿真结果指导,进一步采用物理共混法制备了QDs@SBA-15复合材料,通过透射光谱、荧光激发光谱、紫外-可见光吸收谱等手段对其进行表征并确定浓度配比;最后,将该复合材料与聚二甲基硅氧烷(PDMS)混合固化成膜,并研究了其光致发光性能。实验结果发现,量子点粒径和介孔材料孔径的匹配度以及量子点和有序介孔材料的比例浓度是影响QDs@SBA-15复合材料发光效率及Micro-LED色转换性能的关键因素;通过优化,所得复合材料可获得优异的发光性能以及良好的环境稳定性,相比于纯量子点色转换层,复合材料的光提取效率提升了81.73%,复合材料的环境稳定性提升了14.33%,以Micro-LED作为蓝光光源组成的三基色发光器件工作色域达到了104.52%NTSC。本研究为量子点色转换Micro-LED显示技术提供了理论指导,为实现Micro-LED全彩化开辟了新路径。 展开更多
关键词 量子点 有序介孔材料 色转换 micro-LED
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Lugol's iodine增强Micro-CT成像评估口腔鳞状细胞癌切缘状态的研究
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作者 郁佳鑫 刘鲲宇 +4 位作者 章茜 蒲玉梅 胡勤刚 夏成万 王育新 《口腔医学研究》 CAS CSCD 北大核心 2024年第9期797-802,共6页
目的:本研究拟使用Lugol's iodine增强Micro-CT成像三维评估口腔鳞状细胞癌(oral squamous cell carcinoma,OSCC)切缘状态。方法:本研究共收集68例人OSCC组织样本,所有样本经3%Lugol's iodine染色12 h后行Micro-CT扫描(层厚为50... 目的:本研究拟使用Lugol's iodine增强Micro-CT成像三维评估口腔鳞状细胞癌(oral squamous cell carcinoma,OSCC)切缘状态。方法:本研究共收集68例人OSCC组织样本,所有样本经3%Lugol's iodine染色12 h后行Micro-CT扫描(层厚为50μm)。随后将经Lugol's iodine染色后的样品行常规苏木精-伊红(hematoxylin-eosin,HE)染色切片(厚度为4μm),制作数字化病理切片。分别测量影像图像和病理图像的黏膜切缘(mucosal margin,MM)和深部切缘(deep margin,DM)。结果:Lugol's iodine增强Micro-CT成像可以在三维空间中清晰区分肿瘤边界,且Micro-CT成像相较于二维病理切片,可以更准确地测量MM和DM,发现阳性切缘及临界切缘。结论:Lugol's iodine增强Micro-CT成像可以全面评估OSCC切缘,提供更全面、更清晰的肿瘤边缘信息,指导临床治疗方案选择和预后评估。 展开更多
关键词 口腔鳞状细胞癌 显微计算机断层成像 卢戈氏碘液 三维
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Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity
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作者 Nianwei Xu Renke Kang +4 位作者 Bi Zhang Yuan Zhang Chenxu Wang Yan Bao Zhigang Dong 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期458-475,共18页
Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),... Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining processes.Normal-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue strength.The lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue properties.In this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was developed.Then,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was analyzed.Based on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were furtherpredicted.The predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI indexes.Finally,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted results.According to the critical condition,an SI field where FCI sites appeared in the bulk material could be obtained.In this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%. 展开更多
关键词 surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding
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Feasibility Study of Assist-Linked Brief Intervention for Substance Use Disorders in a Rural Community of Plateau State, Nigeria
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作者 Nwoga Charles Nnaemeka Audu Moses David +4 位作者 Sambo Jacob Dusu Mafai Danboyi Kwei Dakwak Samuel Joseph Ndak Andarawus Zuhumnan Babatunde Stephen 《Open Journal of Psychiatry》 2024年第3期206-222,共17页
Objective: We studied the feasibility of using Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) linked with Brief Intervention (ALBI) in treating Substance Use Disorder in Nigeria. There is a clear ... Objective: We studied the feasibility of using Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) linked with Brief Intervention (ALBI) in treating Substance Use Disorder in Nigeria. There is a clear gap in meeting the needs for treatment and care for people with drug use disorders in Nigeria with many users reporting a self-perceived need for treatment and about 40% of them wanting to receive drug treatment but were unable to access such services. Methods: ASSIST questionnaire was used to gather baseline data, and ALBI along with Motivational Interviewing (MI) was used to intervene for 6 weeks following which ASSIST score was repeated and compared with baseline. Results: Majority of the participants were aged 21 - 30 years, mostly males with (61.3%) lacking steady jobs. Lifetime prevalence of any drug use was (88.2%). Three months prevalence was nicotine (72.0%), alcohol (66.7%), cannabis (47.3%), opioids (11.8%) among others. The ASSIST scores were mostly on the severe ranges. ASSIST result after six weeks showed marked reduction. The Mean Difference (MD) in the ASSIST scores after intervention was significant for tobacco, opioids, alcohol, and cannabis. The Cohen’s D effect size was large for tobacco (1.08), alcohol (0.92) and cannabis (0.73) but low for other substances. Conclusion: ALBI along with MI was helpful in combating the menace of substance use. 展开更多
关键词 assist ALBI SUD Rural Community NIGERIA
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