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N-doped NaTaO3 synthesized from a hydrothermal method for photocatalytic water splitting under visible light irradiation 被引量:5
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作者 Che-Chia Hu Hui-Hsin Huang Yu-Chi Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第3期515-521,共7页
NaTaONcatalysts were synthesized by a hydrothermal(H) and a solid-state(S) methods in this study.The H-and S-NaTaONsamples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), trans... NaTaONcatalysts were synthesized by a hydrothermal(H) and a solid-state(S) methods in this study.The H-and S-NaTaONsamples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), UV–visible(UV–vis) diffuse reflectance spectroscopy, and photoluminescence(PL) spectroscopy. The XRD patterns of the H-and S-samples showed peaks indexed to the pure phase of perovskite NaTaOand minor peaks assignable to TaNat various synthesis temperatures. Substitution of oxygen by nitrogen ions causes the light absorption of the H-and S-NaTaONsamples to be extended to the 600–650 nm region, thus making the samples visible-light active. The NaTaONsamples exhibited photocatalytic activity for Hand Oevolution from aqueous methanol and silver nitrate solutions under visible-light irradiation. The UV–vis and PL spectra of the Hand S-catalysts revealed the presence of cationic vacancies and reduced metallic species, which acted as recombination centers. These results demonstrated that the preparation method plays a critical role in the formation of defect states, thereby governing the photocatalytic activity of the NaTaONcatalysts. 展开更多
关键词 PHOTOCATALYSIS H2 production N-doped NaTaO3 Hydrothermal method visible light
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Effect of Preparation Conditions on Visible Photocatalytic Activity of Titania Synthesized by Solution Combustion Method 被引量:3
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作者 程友萍 孙红旗 +1 位作者 金万勤 徐南平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第2期178-183,共6页
Titania catalysts were synthesized by a solution combustion method (SCM). Photodegradation of 4-chlorophenol (4-CP) using the synthesized catalysts was studied under both visible light (λ≥420nm) and sunlight i... Titania catalysts were synthesized by a solution combustion method (SCM). Photodegradation of 4-chlorophenol (4-CP) using the synthesized catalysts was studied under both visible light (λ≥420nm) and sunlight irradiation. The effect of preparation conditions on photocatalytic activities of the synthesized catalysts was investigated. The optimal photocatalytic activity of the catalyst (denoted as A1 ) was obtained under the following synthesis conditions: ignition temperature of 350~C, fuel ratio ( φ) of 1 and calcination time of lh. The degradation and mineralization ratio of 4-CP were 78.2% and 53.7% respectively under visible light irradiation for 3h using catalyst A1. And the catalyst A1 also showed high photocatalytic activity under sunlight irradiation. 展开更多
关键词 TiO2 solution combustion method PHOTODEGRADATION visible light
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Synthesis of visible light responsive ultrafine K_4Ce_2Nb_(10)O_(30) by a stearic acid method 被引量:2
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作者 陈海群 朱俊武 +2 位作者 马俊兴 庞凯 孙小强 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第5期811-814,共4页
K4Ce2Nb10O30 ultrafine powders were prepared by stearic acid method (SAM). The obtained products were analyzed by X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectrometry, scanning ele... K4Ce2Nb10O30 ultrafine powders were prepared by stearic acid method (SAM). The obtained products were analyzed by X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectrometry, scanning electron microscopy and UV-visible absorption spectra. XRD patterns revealed that K4Ce2Nb10O30 powders treated at 900 oC for 2 h presented tetragonal structure without the presence of deleterious phases. Furthermore, the K4Ce2Nb10O30 prepared by SAM had considerable activity under visible light irradiation. 展开更多
关键词 K4Ce2Nb10O30 stearic acid method visible light responding rare earths
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Simple Method to Fabricate Au Nanoparticle-Decorated TiO2 Nanotube Arrays for Enhanced Visible Light Photocurrent 被引量:2
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作者 陆裕华 王文桂 +1 位作者 翁雨燕 董雯 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期146-149,共4页
Au nanoparticle-decorated TiO2 nanotube arrays are prepared by a simple method, which is a thermal annealing thin gold film deposited on anodie oxidized TiO2 nanotube arrays. These electron microscope images present t... Au nanoparticle-decorated TiO2 nanotube arrays are prepared by a simple method, which is a thermal annealing thin gold film deposited on anodie oxidized TiO2 nanotube arrays. These electron microscope images present that Au nanoparticles are well dispersed within the wall and on the surface of the XiO2 nanotubes. Meanwhile, the morphologies of Au nanoparticles can be controlled by changing the thickness of the deposited gold film. Associ- ated with the excitation of localized surface plasmon resonances, the prepared Au nanoparticle-decorated TiO2 nanotube arrays could work as visible light responsive photocatalysts to produce a greatly enhanced photocurrent density. By varying the initial gold film thickness, such Au nanoparticle-decorated TiO2 nanotube arrays could be optimized to obtain the highest photocurrent generation efficiency in the visible and UV light regions. 展开更多
关键词 TIO As Simple method to Fabricate Au Nanoparticle-Decorated TiO2 Nanotube Arrays for Enhanced visible Light Photocurrent
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New Preparation Method of Visible Light Responsive Titanium Dioxide Photocatalytic Films
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作者 Kaori Nishizawa Masahisa Okada Eiji Watanabe 《Materials Sciences and Applications》 2014年第3期112-123,共12页
We report a new and simple preparation method of the visible light responsive Titanium dioxide (TiO2) photocatalytic films using sol-gel method and ultraviolet light (UV) irradiation. Proposed films were prepared on f... We report a new and simple preparation method of the visible light responsive Titanium dioxide (TiO2) photocatalytic films using sol-gel method and ultraviolet light (UV) irradiation. Proposed films were prepared on fused silica plates using titanium tetra-isopropoxide, urea, 2-methoxyethanol, water and UV irradiation. The 650°C-annealed films were carbon-containing anatase type TiO2, not carbon-doped ones. The prepared films absorbed visible light with wavelengths longer than 400 nm. Also, organic dyes were effectively photodegradated by visible light irradiation in the presence of these films. 展开更多
关键词 TITANIUM Dioxide Films SOL-GEL method UV IRRADIATION visible Light RESPONSIVE PHOTOCATALYST
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Application of Total Error Strategy in Validation of Affordable and Accessible UV-Visible Spectrophotometric Methods for Quality Control of Poor Medicines 被引量:1
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作者 Jérémie Kindenge Mbinze Jean Nsangu Mpasi +8 位作者 Elza Maghe Sébastien Kobo Rodrigue Mwanda Guy Mulumba Jacquie Bolavie Bolande Trésor Menanzambi Bayebila Maguy Borive Amani Philippe Hubert Roland Djang’eing’a Marini 《American Journal of Analytical Chemistry》 2015年第2期106-117,共12页
In the framework of fighting against the poor quality medicines sold in developing countries using classical analytical methods easily accessible in those countries, four UV-Visible spectrophotometric methods for one ... In the framework of fighting against the poor quality medicines sold in developing countries using classical analytical methods easily accessible in those countries, four UV-Visible spectrophotometric methods for one antimalarial (quinine) and two antibiotics (amoxicillin and metronidazole) have been developed and validated according to the total error strategy using the accuracy profiles as a decision tool. The dosing range was 2 - 10 μg/mL (for quinine sulfate in tablet), 4 - 12 μg/mL (for quinine bichlorhydrate in oral drop-metronidazole benzaote in oral suspension) and 15 - 35 μg/mL (for amoxicillin trihydrate in capsule). The validated methods were then applied in determining the content of some analogous medicines sold in the Democratic Republic of Congo. Thus, the proposed UV-Visible spectrophotometric methods are simple and suitable to quantify quinine, amoxicillin and metronidazole in different pharmaceutical forms. 展开更多
关键词 POOR Quality MEDICINES UV-visible Spectrophotometric methods QUININE Amoxicillin METRONIDAZOLE VALIDATION Total Error Accuracy Profiles
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(N,F)-codoped TiO_2 Nanocrystals as Visible Light-activated Photocatalyst 被引量:3
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作者 Yanling Meng Jiansong Chen Ying Wang Hanming Ding Yongkui Shan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2009年第1期73-76,共4页
(N, F)-codoped anatase TiO2 nanocrystals with active visible light response were prepared by using a simple sol-gel approach. X-ray photoelectron spectroscopy measurements suggested that the substitutional N and F s... (N, F)-codoped anatase TiO2 nanocrystals with active visible light response were prepared by using a simple sol-gel approach. X-ray photoelectron spectroscopy measurements suggested that the substitutional N and F species replaced the lattice oxygen atoms in TiO2 nanocrystals. Such nanocrystals showed strong absorption from 400 to 550 nm, which was mainly induced by nitrogen doping. The phase transformation from anatase to rutile was hindered by fluorine doping at high calcination temperatures, which was verified by XRD patterns. The N2 adsorption-desorption isotherms revealed the absence of mesopores in these nanocrystals. The (N, F)- codoped TiO2 nanocrystals showed satisfying photocatalytic activity on the photo-degradation of methylene blue under visible light. 展开更多
关键词 TiO2 nanocrystal (N F)-codoping Sol-gel method visible light photocatalyst
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In-Situ Hydrothermal Synthesis of Bi–Bi2O2CO3 Heterojunction Photocatalyst with Enhanced Visible Light Photocatalytic Activity 被引量:4
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作者 Prasenjit Kar Tuhin Kumar Maji +2 位作者 Ramesh Nandi Peter Lemmens Samir Kumar Pal 《Nano-Micro Letters》 SCIE EI CAS 2017年第2期58-67,共10页
Bismuth containing nanomaterials recently received increasing attention with respect to environmental applications because of their low cost, high stability and nontoxicity. In this work, Bi–Bi_2O_2CO_3 heterojunctio... Bismuth containing nanomaterials recently received increasing attention with respect to environmental applications because of their low cost, high stability and nontoxicity. In this work, Bi–Bi_2O_2CO_3 heterojunctions were fabricated by in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets via a simple hydrothermal synthesis approach. X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and high-resolution TEM(HRTEM) were used to confirm the morphology of the nanosheet-like heterostructure of the Bi–Bi_2O_2CO_3 composite. Detailed ultrafast electronic spectroscopy reveals that the in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets exhibit a dramatically enhanced electron-hole pair separation rate, which results in an extraordinarily high photocatalytic activity for the degradation of a model organic dye, methylene blue(MB) under visible light illumination. Cycling experiments revealed a good photochemical stability of the Bi–Bi_2O_2CO_3 heterojunction under repeated irradiation. Photocurrent measurements further indicated that the heterojunction incredibly enhanced the charge generation and suppressed the charge recombination of photogenerated electron-hole pairs. 展开更多
关键词 Bi nanoparticles Bi–Bi2O2CO3 nanosheets HETEROJUNCTION Hydrothermal method Charge separation visible light photocatalytic activity
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Determination of Thioglucoside in Cabbage by Using the Ultraviolet-visible Light Spectrophotometer
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作者 WANGJing WANGQing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第2期149-157,共9页
The ultraviolet-visible light spectrophotometer method was adopted to determine thioglucoside in cabbage with the seeds.Individual plant of cabbage was used as test materials,palladium chloride as complexing agent and... The ultraviolet-visible light spectrophotometer method was adopted to determine thioglucoside in cabbage with the seeds.Individual plant of cabbage was used as test materials,palladium chloride as complexing agent and sodium cellulose glycolate as dispersing agent.The results showed that palladiumd thioglucoside method could be taken as a quick,easy and precise quantitative analysis method to determine thioglucoside in cabbage. 展开更多
关键词 Ultraviolet visible light spectrophotometer method CABBAGE thioglucoside determination method
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Mass Production of Bi3NbO7/Bi2Zn(2/3)Nb(4/3)O7 Composites and Their Visible-light Photocatalytic Activity
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作者 彭代江 ZOU Zhengguang +3 位作者 HE Jinyun 龙飞 MO Shuyi ZHOU Huanfu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第2期403-407,共5页
Series Bi3NbO7/Bi2Zn(2/3)Nb(4/3)O7 (BN/BZN) composites were synthesized through a facile solid state reaction method. The products were characterized by X-ray diffraction(XRD), field emission scanning electron... Series Bi3NbO7/Bi2Zn(2/3)Nb(4/3)O7 (BN/BZN) composites were synthesized through a facile solid state reaction method. The products were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM) and UV-vis diffuse reflectance spectroscopy(DRS). When BN: BZN=0.1 mole ratio, the BN/BZN composite showed the best visible-light-driven photocatalytic performance, which decomposed nearly 100% of Rh B(10 ppm, p H=3-4) within 40 min. The results demonstrated that in-situ solid state synthesis of BN/BZN composites could be an efficient strategy to develop new photocatalyst for environmental remediation. 展开更多
关键词 visible-light-driven photocatalyst Bi3NbO7/Bi2Zn(2/3)Nb(4/3)O7 composites solid state reaction method
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紫外分光光度法测定歧化松香中去氢枞酸含量的干扰因素研究
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作者 王宏晓 沈娟章 +1 位作者 马艳 谭卫红 《林产化学与工业》 CAS CSCD 北大核心 2024年第3期30-36,共7页
利用液相色谱仪、制备液相色谱仪、气相色谱质谱联用仪,对歧化松香(DR)中去氢枞酸(DA)紫外光谱测定方法的干扰因素进行了详细研究。测定的市售不同省份的5个样品中有2个主要干扰物质,进一步定性,确定干扰物质1为6,8,11,13-枞四烯酸(ATA)... 利用液相色谱仪、制备液相色谱仪、气相色谱质谱联用仪,对歧化松香(DR)中去氢枞酸(DA)紫外光谱测定方法的干扰因素进行了详细研究。测定的市售不同省份的5个样品中有2个主要干扰物质,进一步定性,确定干扰物质1为6,8,11,13-枞四烯酸(ATA),干扰物质2为混合物,主要检出物为去氢枞醛(D)和枞酸(AA)。采用二阶导数光谱法和偏最小二乘(PLS)法对紫外光谱数据进行分析,以消除去氢枞酸紫外分光光度法的干扰,结果表明:PLS法比二阶导数光谱法误差更小,能够同时消除多种干扰因素,使测试结果更加接近真实值。 展开更多
关键词 歧化松香 紫外可见分光光度法 干扰因素 偏最小二乘法
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可见光室内定位技术研究进展
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作者 陈静 刘旋 郑杰 《电讯技术》 北大核心 2024年第3期478-487,共10页
可见光赋能的定位技术具有无电磁辐射、成本低、精度高、安全性高、不易受电磁干扰等优势,故近年来可见光室内定位技术(Visible Light Indoor Positioning,VLIP)受到了学界和业界的广泛关注。为了展示VLIP的研究进展和发展全貌,阐述了V... 可见光赋能的定位技术具有无电磁辐射、成本低、精度高、安全性高、不易受电磁干扰等优势,故近年来可见光室内定位技术(Visible Light Indoor Positioning,VLIP)受到了学界和业界的广泛关注。为了展示VLIP的研究进展和发展全貌,阐述了VLIP的系统架构及相关通信技术,对VLIP基础定位方法及其相关辅助定位技术进行了详细地梳理、分类和对比分析,针对VLIP当前面临的挑战分析了潜在的解决方案,展望了VLIP未来研究方向。 展开更多
关键词 可见光通信(VLC) 可见光室内定位(VLIP) 定位方法 LED
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船舶超大空间火灾环境下人员疏散模型
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作者 张海鹏 李语松 +1 位作者 陈淼 郭明阳 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第1期53-61,共9页
针对船舶超大空间火灾对人员疏散能力的影响难以量化问题,本文基于元胞自动机理论,构建了一种行人个体自主分析火灾环境下温度和能见度影响的疏散模型(cellular automata model considering visibility and temperature, CAVT)。CAVT模... 针对船舶超大空间火灾对人员疏散能力的影响难以量化问题,本文基于元胞自动机理论,构建了一种行人个体自主分析火灾环境下温度和能见度影响的疏散模型(cellular automata model considering visibility and temperature, CAVT)。CAVT模型采用Sigmoid函数和历史实验数据建立温度、能见度与人员运动能力的映射关系,基于FDS数值模拟结果建立火灾环境场对人员个体运动能力影响的时空耦合关系,使用熵值法计算温度场和能见度场在火灾环境场中的权重。以某客船超大空间为例开展研究分析,结果表明:火灾环境下人员疏散时间受火源功率影响较大,火源位置影响较小,出口宽度大于3 m,不影响疏散效率。与Pathfinder软件相比,CAVT模型可更准确模拟人员因高温和低能见度导致的运动能力的动态下降反馈。 展开更多
关键词 船舶超大空间火灾 SIGMOID函数 人员疏散 熵值法 元胞自动机 能见度
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基于生成对抗网络的路况监控视频能见度检测方法
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作者 裴志松 时兵 《信息与电脑》 2024年第6期129-131,共3页
传统路况监控视频能见度检测方法直接对人眼可分辨最远点进行检测,未进行车道线检测及兴趣域提取,造成传统方法检测效果较差。对此,提出基于生成对抗网络的路况监控视频能见度检测方法。在车道线检测及兴趣域提取的基础上,基于生成对抗... 传统路况监控视频能见度检测方法直接对人眼可分辨最远点进行检测,未进行车道线检测及兴趣域提取,造成传统方法检测效果较差。对此,提出基于生成对抗网络的路况监控视频能见度检测方法。在车道线检测及兴趣域提取的基础上,基于生成对抗网络检测人眼可分辨最远点,进一步与计算机视觉和图形领域相结合,实现路况监控视频能见度检测。实验结果表明,该方法具有更好的检测效果,可推广应用。 展开更多
关键词 生成对抗网络 路况监控 能见度 检测方法
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面向水面无人艇的船舶舷号识别方法 被引量:1
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作者 张韧然 张磊 苏玉民 《中国舰船研究》 CSCD 北大核心 2024年第1期46-54,共9页
[目的]针对水面船舶舷号检测问题,提出一种面向水面无人艇的实时船舶舷号检测方法。[方法]基于原始的单阶段目标检测模型(YOLO),引入注意力机制,利用空间信息交互模块和分割注意力融合方法,提升神经网络对重要目标区域的敏感度。考虑先... [目的]针对水面船舶舷号检测问题,提出一种面向水面无人艇的实时船舶舷号检测方法。[方法]基于原始的单阶段目标检测模型(YOLO),引入注意力机制,利用空间信息交互模块和分割注意力融合方法,提升神经网络对重要目标区域的敏感度。考虑先验知识对模型精度的影响,结合自适应锚框算法和正样本增强策略提高回归精度。针对深度神经网络(DNN)收敛困难的问题,改进损失函数,在保证网络收敛速度的同时提高神经网络训练的稳定性。最后,将改进的目标检查模型部署在无人艇上进行有效性验证。[结果]结果表明,所提算法在3级海情下能够准确识别船舶目标及其标志舷号,相比于原模型,改进后的YOLO算法在全类平均精度(mAP)方面提高了14%,识别速度满足实时要求。[结论]研究证明了所提舷号检测方法满足无人艇实时识别舷号任务的要求,并在复杂海洋环境中仍然具备识别能力。 展开更多
关键词 无人艇 舷号检测 可见光图像 YOLO算法 改进方法
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Key points and visible part fusion attention network for occluded pedestrian detection in traffic environments 被引量:1
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作者 LIU Peiyu MA Yixuan 《Optoelectronics Letters》 EI 2024年第7期430-436,共7页
Aiming at the problem of low detection accuracy of occluded pedestrian in traffic environments,this paper proposes a key points and visible part fusion network for occluded pedestrian detection.The proposed algorithm ... Aiming at the problem of low detection accuracy of occluded pedestrian in traffic environments,this paper proposes a key points and visible part fusion network for occluded pedestrian detection.The proposed algorithm constructs two attention modules by introducing human key points and the bounding box of visible parts respectively,which suppresses the occluded parts in the channel features and spatial features of pedestrian features respectively.Experimental results on CityPersons and Caltech datasets demonstrate the effectiveness of the proposed algorithm.The missing rate(MR)is reduced to 40.78 on the Heavy subset of the CityPersons dataset and surpasses many outstanding methods. 展开更多
关键词 methods. NETWORK visible
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关于注射剂中可见异物研究进展
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作者 徐晓晴 王新雨 +4 位作者 张晓明 张启明 徐昕怡 尚悦 张军 《中国药事》 CAS 2024年第6期696-704,共9页
注射剂可见异物是目前注射剂产品常见的问题之一,也一直是全球监管机构和行业内激烈讨论的问题。尽管业界对可见异物的定义及判断标准有一定的共识,但在实际生产过程中,对于如何控制可见异物仍然存在不同的理解和掌握尺度。此外,企业在... 注射剂可见异物是目前注射剂产品常见的问题之一,也一直是全球监管机构和行业内激烈讨论的问题。尽管业界对可见异物的定义及判断标准有一定的共识,但在实际生产过程中,对于如何控制可见异物仍然存在不同的理解和掌握尺度。此外,企业在生产过程中对于检测人员的技能要求和设备的验证也缺乏权威的参考和依据,如可见异物的标准物质和相关技术指导文件等,这些对于国内注射剂的生产和质量控制影响都很大。本研究旨在开展关于“注射剂中可见异物”的文献调查,通过收集和整理国内外相关文献,对本领域的相关研究进展进行分析总结,为提高注射剂质量提供参考。 展开更多
关键词 注射剂 可见异物 来源及控制 检查方法 质量控制
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室内可见光定位智能优化方法研究进展
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作者 郑杰 刘旋 陈静 《光通信技术》 北大核心 2024年第2期48-55,共8页
室内可见光定位(VIP)是室内定位领域的研究热点,近年来越来越多采用人工智能的方法来优化和提升VIP的定位精度与效率。为了展示VIP智能优化方法的最新研究进展,首先归纳了VIP的相关概念与适用场景,并详细介绍了电磁严苛、热点高容量和... 室内可见光定位(VIP)是室内定位领域的研究热点,近年来越来越多采用人工智能的方法来优化和提升VIP的定位精度与效率。为了展示VIP智能优化方法的最新研究进展,首先归纳了VIP的相关概念与适用场景,并详细介绍了电磁严苛、热点高容量和无线信号传播受阻3种场景下的VIP应用,并与传统室内定位(IP)的可适性进行对比,对VIP定位方法进行分类;详细梳理了近年来提出的VIP智能优化方法,最后归纳了该领域的共性问题和挑战。 展开更多
关键词 可见光通信 室内定位 优化方法 人工智能 机器学习
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基于可见/近红外光谱对葡萄可溶性固形物无损检测研究
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作者 吴虹璋 蔡红星 +4 位作者 任玉 王婷婷 周建伟 李栋梁 曲冠男 《光散射学报》 北大核心 2024年第1期44-51,共8页
葡萄中可溶性固形物是评价葡萄成熟度的重要指标,本文探究了基于可见/近红外光谱技术对多个品种葡萄(红提、巨峰、辽峰)可溶性固形物(Soluble Solid Content,SSC)含量进行定量分析。分别采集了三个葡萄品种在550~960 nm波长范围内的透... 葡萄中可溶性固形物是评价葡萄成熟度的重要指标,本文探究了基于可见/近红外光谱技术对多个品种葡萄(红提、巨峰、辽峰)可溶性固形物(Soluble Solid Content,SSC)含量进行定量分析。分别采集了三个葡萄品种在550~960 nm波长范围内的透射光谱数据,采用Savitzky-Golay卷积平滑(S-G)、标准正态变换(Standard Normal Variate,SNV)、小波变换(WT)、一阶求导+S-G卷积平滑组合(1stDer+S-G)预处理方法,对比分析出最适合各个品种的预处理方法;然后在最佳的预处理方法下采用连续投影算法(SPA)、竞争性自适应重加权(CARS)对光谱进行特征波长选择;结合化学计量学方法分别建立多品种与单一品种的偏最小二乘回归(PLSR)、BP神经网络SSC含量无损预测模型。结果表明,基于BP-SPA建立的SSC含量模型最优,多个品种通用SSC含量预测模型的预测集相关系数(Rp 2)为0.85,表明基于可见/近红外光谱技术对多个葡萄品种SSC含量无损检测是可行的。 展开更多
关键词 可见/近红外光谱 可溶性固形物 偏最小二乘 无损检测 BP神经网络
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碳量子点双光法检测溶液中的钴离子
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作者 刘炉英 刘莹娜 +2 位作者 马海瑜 吴家婷 谢丽君 《广州化工》 CAS 2024年第21期79-82,152,共5页
发现合成的碳量子点加入钴离子后溶液变成绿色,在650 nm处有紫外吸收,适用检测范围为0.8~35 mmol/L,方程式为y=0.007 46x+0.219 51,R^(2)=0.998 2;当钴离子浓度为0.04~6 mmol/L能猝灭碳量子点的荧光,浓度的对数与F_(0)/F比值呈现线性相... 发现合成的碳量子点加入钴离子后溶液变成绿色,在650 nm处有紫外吸收,适用检测范围为0.8~35 mmol/L,方程式为y=0.007 46x+0.219 51,R^(2)=0.998 2;当钴离子浓度为0.04~6 mmol/L能猝灭碳量子点的荧光,浓度的对数与F_(0)/F比值呈现线性相关系数R^(2)=0.996,线性方程为:y=0.565 3x+1.739 6。因此,当钴离子浓度为0.8~6.0 mmol/L时,此碳量子点能达到双光法检测溶液中的钴离子,通过加标回收自来水样验证双光法检测有效。 展开更多
关键词 碳量子点 钴离子 紫外可见吸收光谱法 荧光法
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