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基于非稳态随机过程的近红外反射率鲁棒估计算法
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作者 房卓群 于晓升 +3 位作者 贾同 吴成东 李永强 许茗 《控制与决策》 EI CSCD 北大核心 2019年第6期1151-1159,共9页
反射率估计在计算机视觉、计算机图形学等领域具有重要作用.为了精确获取反射率,提出一种基于非稳态随机过程的近红外反射率鲁棒估计算法(RENA).该算法以Kinect二代传感器采集结果计算初始反射率,并建立反射率加性噪声模型,同时提出光... 反射率估计在计算机视觉、计算机图形学等领域具有重要作用.为了精确获取反射率,提出一种基于非稳态随机过程的近红外反射率鲁棒估计算法(RENA).该算法以Kinect二代传感器采集结果计算初始反射率,并建立反射率加性噪声模型,同时提出光照度鲁棒估计的概念,简化反射率图像非稳态随机过程模型.实验表明, RENA算法的反射率估计结果优于其他去噪算法,适用于室内场景的反射率图像高精度估计. 展开更多
关键词 近红外光 反射率 鲁棒估计 随机过程 深度图像 红外图像
Titanium dioxide as an adsorbent to enhance the detection ability of near-infrared diffuse reflectance spectroscopy
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作者 Shuyu Wang Jin Zhang +1 位作者 Wensheng Cai Xueguang Shao 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第5期1024-1026,共3页
A method for quantitative determination of fish sperm deoxyribonucleic acid(fsDNA)was developed by using titanium dioxide(TiO2)as an adsorbent and near-infrared diffuse reflectance spectroscopy(NIRDRS).The selective e... A method for quantitative determination of fish sperm deoxyribonucleic acid(fsDNA)was developed by using titanium dioxide(TiO2)as an adsorbent and near-infrared diffuse reflectance spectroscopy(NIRDRS).The selective enrichment of fsDNA was proved by comparing the adsorption efficiency of bovine serum albumin,tyrosine and tryptophan,and the low adsorption background of TiO2 was illustrated by comparing the spectra of four commonly-used inorganic adsorbents(alkaline aluminium oxide,neutral aluminium oxide,nano-hydroxyapatite and silica).The spectral feature of fsDNA can be clearly observed in the spectrum of the sample.Partial least squares(PLS)model was built for quantitative determination of fsDNA using 28 solutions,and 13 solutions with interferences were used for validation of the model.The results showed that the correlation coefficient(R)between the predicted and the reference concentration is 0.9727 and the recoveries of the validation samples are in the range of 98.2%-100.7%. 展开更多
关键词 NEAR-INFRARED DIFFUSE reflectance spectroscopy Quantitative model DETECTION ABILITY Titanium dioxide Fish SPERM DNA
近红外荧光探针在细胞与生命体中对重金属离子检测的研究进展 预览
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作者 吴万豪 方垚 +6 位作者 罗登旺 王永好 王永净 李小娟 李春艳 陈敬华 兰建明 《广东化工》 CAS 2019年第12期73-75,共3页
工业生产中产生的重金属离子如果没有经过处理即排放到自然界中就会造成重金属污染,导致严重的健康和环境问题。因此,重金属离子的检测非常重要。本文介绍了近年来近红外荧光探针在细胞与生命体中对重金属离子检测的研究进展,并讨论了... 工业生产中产生的重金属离子如果没有经过处理即排放到自然界中就会造成重金属污染,导致严重的健康和环境问题。因此,重金属离子的检测非常重要。本文介绍了近年来近红外荧光探针在细胞与生命体中对重金属离子检测的研究进展,并讨论了近红外荧光探针在重金属离子检测方面的发展方向。 展开更多
关键词 重金属离子 近红外 荧光探针 检测
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Luminescent properties of Ce3+,Er3+ co-doped La3Si6N11
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作者 Yuan Xue Ronghui Liu +5 位作者 Yuanhong Liu Huibing Xu Guantong Chen Xia Zhang Wei Gao Ze Jiang 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第3期248-252,共5页
In order to obtain near-infrared phosphor pumped by blue chip with high luminous efficiency, a novel near-infrared phosphor Ce3+/Er3+ doped La3Si6N11 was designed and firstly prepared via conventional solid-state reac... In order to obtain near-infrared phosphor pumped by blue chip with high luminous efficiency, a novel near-infrared phosphor Ce3+/Er3+ doped La3Si6N11 was designed and firstly prepared via conventional solid-state reactions. The structure and morphology of Ce3+/Er3+ doped La3Si6N11 were investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM). Compared with Er3+ doped La3Si6N11,the emission intensity of the Ce3+, Er3+ co-doped phosphor can be increased more than 5 times.Meanwhile, the mechanism of energy transfer from Ce3+ to Er3+ is confirmed according to the excitation,emission spectra and decay lifetimes curve. Above results suggest that La3 Si6 N11:Ce3+,Er3+ is a promising near-infrared phosphor for blue pumped LEDs(light-emitting diodes). 展开更多
关键词 Solid state reaction Energy transfer NEAR-INFRARED PHOSPHOR La3Si6N11:Ce3+ ER3+ Rare earths
基于灰度变化方向的指静脉特征检测算法 预览
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作者 熊显名 唐绮雯 张文涛 《现代电子技术》 北大核心 2019年第3期61-64,共4页
针对目前指静脉特征纹路提取不准确、特征纹路断裂、噪声过多、提取过程复杂等问题,采用近红外光电透射式静脉获取方式采集指静脉图像。在预处理阶段设计了四点法对图像的静脉区域与背景区域进行快速分离,通过分析静脉灰度特征,设计垂... 针对目前指静脉特征纹路提取不准确、特征纹路断裂、噪声过多、提取过程复杂等问题,采用近红外光电透射式静脉获取方式采集指静脉图像。在预处理阶段设计了四点法对图像的静脉区域与背景区域进行快速分离,通过分析静脉灰度特征,设计垂直于静脉纹路走向的四方向特征模板检测算子对手指静脉进行特征提取与实验。应用该算法,能快速准确提取静脉特征纹路,降低特征纹路断裂问题,提取过程简单且算法效率较高,在提取单幅静脉纹路特征速度可达到1.14ms。 展开更多
关键词 指静脉 特征提取 灰度变化 方向检测 四点法 近红外 生物识别
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Visual dual chemodynamic/photothermal therapeutic nanoplatform based on superoxide dismutase plus Prussian blue
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作者 Shan Lei Jinxing Chen +2 位作者 Kun Zeng Mozhen Wang Xuewu Ge 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第5期1071-1082,共12页
Enzyme-based anticancer therapy is more attractive for the less side effect than conventional chemotherapy.However,the poor stability and low membrane permeability of enzymes during the intracellular delivery are cons... Enzyme-based anticancer therapy is more attractive for the less side effect than conventional chemotherapy.However,the poor stability and low membrane permeability of enzymes during the intracellular delivery are constraints for its practical applications.In this work,we synthesized novel near-infrared (NIR)-responsive core-shell-structured Prussian blue@fibrous SiO2 (PBFS) nanoparticles as the carrier of superoxide dismutase (SOD) and a glutathione (GSH)-activated Fenton reagent (DiFe).The PBFS nanoparticles are further modified with aGSH-responsive cationic polymer (poly(2-(acryloyloxy)-N,N-dimethyl-N-(4-(((2-((2-(((4-methyl-2-oxo-2H-chromen-7-yl)carbamoyl)oxy)ethyl)disulfaneyl)ethoxy)carbonyl)amino)benzyl)ethan-1-aminium,PSS) containing disulfide bonds and fluorophores.After SOD and DiFe are loaded on the PBFS-PSS nanoparticles,dual chemodynamic/photothermal therapeutic nanoparticulate systems (PBFS-PSS/DiFe/SOD) are obtained.In vitro experiments show that PBFS-PSS/DiFe/SOD nanoparticles have good biocompatibility and can be tracked under fluorescence microscope during the intracellular delivery process in MCF-7 tumor cells due to the GSH-activated release of fluorophores.They also exhibit high efficiency in NIR photothermal conversion and GSH-activated Fenton reaction in tumor cells,thus achieving high-efficient killing effect of tumor cells based on the combination of photothermal and chemodynamic therapeutic performance (PTT and CDT).This work offers a novel pathway to construct a visual multifunctional nanomedicine platform for future cancer therapy. 展开更多
关键词 copper-zinc superoxide DISMUTASE Fenton REAGENT Prussian blue NEAR-INFRARED (NIR) PHOTOTHERMAL therapy fluorescence
食品光谱图像无损检测技术实用化方向研究进展 预览
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作者 王飞翔 谢安国 +2 位作者 康怀彬 刘云宏 于慧春 《农产品加工》 2019年第13期74-78,共5页
光谱分析和光谱成像等光学检测技术具有快速、无损、精准等特点,在食品检测领域的研究越来越广泛。将先进技术从实验室理论研究推向工业生产中的实际应用,实现技术转化一直是科研工作的重要目标。通过简述光谱及图像分析技术的基本原理... 光谱分析和光谱成像等光学检测技术具有快速、无损、精准等特点,在食品检测领域的研究越来越广泛。将先进技术从实验室理论研究推向工业生产中的实际应用,实现技术转化一直是科研工作的重要目标。通过简述光谱及图像分析技术的基本原理和设备结构,对比用于科研分析与生产实用中的设备在设计上差异。综述近年来基于光谱和图像分析技术所开发的实用化在线式或便携式设备在食品生产和检测中的研究进展,以期为我国食品安全检测技术发展及设备开发提供理论依据和参考。 展开更多
关键词 光学检测 近红外 高光谱 食品检测 进展
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A Novel Approach to Measure the Total Antioxidant Power of Wines through Near Infrared Spectroscopy and Its Relevance in Human Nutrition 预览
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作者 Raúl Francisco Pastor María Laura Mariani +6 位作者 Marianela G. Villach Pablo N. Cascón Miriam Giudice Elena Pastor Isabel Pastor Roberto H. Iermoli Alicia B. Penissi 《健康科学:英文版》 2019年第4期209-214,共6页
Wine is the product of the alcoholic fermentation of the grape (Vitis vinifera). As such, it is a hydroalcoholic solution with a variable content of nutritional and functional (polyphenols) molecules, the latter invol... Wine is the product of the alcoholic fermentation of the grape (Vitis vinifera). As such, it is a hydroalcoholic solution with a variable content of nutritional and functional (polyphenols) molecules, the latter involved in its antioxidant potential. The organoleptic variables of wine, together with its potential positive effects on health of a light-moderate intake, have always been topics of great interest within the cultures. In the label of wine, alcohol is the only declared variable. On the other hand, there is no information about the content of “positive” molecules, such as those associated with the antioxidant power. This value could be very important to classify the wines, helping oenologist and nutritionist in qualifying them as a component of Mediterranean diet. Moreover, one of the most critical aspects in evaluating the role of wine in human health through epidemiological prospective studies is the quality of the products used and their antioxidant potential. This research aimed to optimize and validate an analytical approach based on a portable device (SCIO?), using NIRS (near-infrared reflectance spectroscopy). It allows the measure of TAP (total antioxidant power) of wine through the glass. Research findings are promising. To the best of our knowledge, this is the first time that an easy-to-use and cheap hand-held scanner is validated to measure the TAP of a beverage. 展开更多
关键词 TAP of WINES NEAR-INFRARED spectroscopy of WINES NIRS portable device
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Factors influencing near infrared spectroscopy analysis of agro-products: a review
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作者 Xiao XU Lijuan XIE Yibin YING 《农业科学与工程前沿:英文版》 2019年第2期105-115,共11页
The near infrared (NIR) spectroscopy technique has wide applications in agriculture with the advantages of being nondestructive, sensitive, safe and rapid. However, there are still more than 40 error sources influenci... The near infrared (NIR) spectroscopy technique has wide applications in agriculture with the advantages of being nondestructive, sensitive, safe and rapid. However, there are still more than 40 error sources influencing the robustness and accuracy of its calibration and operation. Environmental, sample and instrument factors that influence the analysis are discussed in this review, including temperature, humidity and other factors that introduce uncertainty. Error sources from livestock products, fruit and vegetables, which are the most common objects in the field of NIR analysis, are also emphasized in the second part. In addition, studies utilizing different instruments, spectral pretreatments, variable selection methods, wavelength ranges, detection modes and calibration methods are tabulated to illustrate the complications they introduce and how they influence NIR analysis. It is suggested that large scale of data with abundant varieties can be used to build a more robust calibration model, in order to improve the robustness and accuracy of the NIR analytical model, and overcome problems caused by confining analysis to too many uniform samples. 展开更多
关键词 agro-product ERROR SOURCE influence factor NEAR INFRARED SPECTROSCOPY
应用于天然气的近红外CO气体分析系统的实验研究 预览
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作者 李国林 刘文雅 季文海 《红外与激光工程》 EI CSCD 北大核心 2019年第A01期120-125,共6页
基于CO气体分子在1.56μm处的泛频吸收带,结合波长调制技术和谐波检测技术,采用长光程气体吸收池,研制了一种应用于天然气的CO浓度分析系统。该系统主要由激光器驱动模块(压控恒流源和温度控制电路)、Herriot型气体吸收池气室、锁相放... 基于CO气体分子在1.56μm处的泛频吸收带,结合波长调制技术和谐波检测技术,采用长光程气体吸收池,研制了一种应用于天然气的CO浓度分析系统。该系统主要由激光器驱动模块(压控恒流源和温度控制电路)、Herriot型气体吸收池气室、锁相放大电路等信号处理模块构成。利用混合模拟气站模拟天然气环境,配备不同标准浓度的CO气体,经实验验证,该分析系统的最低检测下限5.6 ppm(1 ppm=10-6),浓度为0.05%的CO气体的相对误差小于2%;对于10%浓度的标准CO气体的相对误差小于1.8%。当被测CO气体浓度在0~100 ppm范围时,其系统检测灵敏度为0.09 mV/ppm;同采用QCL(Quantum Cascade Laser)的CO检测系统相比,该系统具有性价比高、适用于复杂油气开发场合等优势,在石油化工天然气领域具有很大的应用价值。 展开更多
关键词 近红外 光电检测 光谱吸收 天然气
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近红外结合极限学习机快速识别牛肉中掺假猪肉 预览
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作者 韩方凯 刘璨 +4 位作者 黄煜 马梅 冯凡 段腾飞 张东京 《安徽农业科学》 CAS 2019年第13期185-187,共3页
[目的]建立牛肉中掺假猪肉的快速鉴定方法。[方法]采用傅立叶变换近红外结合极限学习机(extreme learning machine,ELM)构建纯牛肉、牛肉中掺假猪肉、纯猪肉的快速识别模型,考察标准正态变换、多元散射校正(multiplicative scatter corr... [目的]建立牛肉中掺假猪肉的快速鉴定方法。[方法]采用傅立叶变换近红外结合极限学习机(extreme learning machine,ELM)构建纯牛肉、牛肉中掺假猪肉、纯猪肉的快速识别模型,考察标准正态变换、多元散射校正(multiplicative scatter correction,MSC)、一阶导数及二阶导数结合核主成分分析(kernel principal componentan alysis,KPCA)等光谱预处理方法对ELM模型预测性能的影响。[结果]MSC+KPCA预处理下,ELM模型的预测效果最优,训练集及测试集的正确识别率分别为86.67%和83.33%。[结论]近红外光谱技术结合ELM在牛肉中掺假猪肉的快速鉴定方面具有较大的潜力。 展开更多
关键词 牛肉掺假 近红外 极限学习机 核主成分分析
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基于近红外光谱技术的纺织品判别分析 预览
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作者 邱笛 胡春琼 +1 位作者 陈昱岑 谭超 《化工时刊》 CAS 2019年第3期23-27,共5页
近红外光谱技术是一种分析速度快、不破坏样品的绿色分析方法,在纺织品的成分检测方面具极大作用。本文利用近红外光谱技术对涤纶、腈纶、锦纶、羊绒、驼绒、兔绒、羊/涤样品进行定性判别分析。通过主成分分析法得到羊绒混涤纶光谱所呈... 近红外光谱技术是一种分析速度快、不破坏样品的绿色分析方法,在纺织品的成分检测方面具极大作用。本文利用近红外光谱技术对涤纶、腈纶、锦纶、羊绒、驼绒、兔绒、羊/涤样品进行定性判别分析。通过主成分分析法得到羊绒混涤纶光谱所呈递的主要信息,采用化学计量学方法对光谱进行预处理,剔除异常光谱。通过马氏距离判断分析类别,取得了较为良好的效果。 展开更多
关键词 纺织品 近红外 定性判别
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A theranostic agent for cancer therapy and imaging in the second nearinfrared window
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作者 Zhuoran Ma Hao Wan +10 位作者 Weizhi Wang Xiaodong Zhang Takaaki Uno Qianglai Yang Jingying Yue Hongpeng Gao Yeteng Zhong Ye Tian Qinchao Sun Yongye Liang Hongjie Dai 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第2期273-279,共7页
Thera no stic nano particles are integrated systems useful for simulta neous diag nosis and imaging guided delivery of therapeutic drugs, with wide ranging pote ntial applicati ons in the clinic. Here we developed a t... Thera no stic nano particles are integrated systems useful for simulta neous diag nosis and imaging guided delivery of therapeutic drugs, with wide ranging pote ntial applicati ons in the clinic. Here we developed a thera no stic nan oparticle (~24 nm size by dynamic light scatteri ng) p-FE-PTX-FA based on polymeric micelle encapsulating an organic dye (FE) fluorescing in the 1,000-1,700 nm second near-infrared (NIR-Ⅱ) window and an an ti-ca ncer drug paclitaxel. Folic acid (FA) was conjugated to the nan oparticles to afford specific binding to molecular folate receptors on muri ne breast can cer 4T1 tumor cells. In vivo, the nan oparticles accumulated in 4T1 tumor through both passive and active targeting effect. Under an 808 nm laser excitation, fluorescence detection above 1,300 nm afforded a large Stokes shift, allowing targeted molecular imaging tumor with high signal to background ratios, reaching a high tumor to normal tissue signal ratio (T/NT) of (20.0±2.3). Further, 4T1 tumors on mice were completed eradicated by paclitaxel released from p-FE-PTA-FA within 20 days of the first injection. Pharmacokinetics and histology studies indicated p-FE-PTX-FA had no obvious toxic side effects to major organs. This represented the first NIR-Ⅱ theranostic age nt developed. 展开更多
关键词 THERANOSTIC nanoparticles SECOND NEAR-INFRARED WINDOW fluorescenee IMAGING cancer therapy
近红外光谱法快速检测白酒基酒中甲醇含量 预览
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作者 张金玲 《酿酒》 CAS 2019年第3期120-122,共3页
使用近红外光谱类型检测技术对白酒基酒当中的甲醇物质含量进行了检验,在完成了光谱信息数据采集之后对数据进行了有效处理,运用偏最小二乘法建立起甲醇物质定量分析模型。在对模型进行了优化处理之后,确定最佳效果的预处理方式是将一... 使用近红外光谱类型检测技术对白酒基酒当中的甲醇物质含量进行了检验,在完成了光谱信息数据采集之后对数据进行了有效处理,运用偏最小二乘法建立起甲醇物质定量分析模型。在对模型进行了优化处理之后,确定最佳效果的预处理方式是将一阶导数方程和矢量均归一化,分析得主要成分数数值为2,最佳波段的谱值在6102到5450厘米之间。通过相应处理方式使待处理样品的真实数值和预测数值的具体决定系数数值为0.955,将标准偏差数值校正为1.30。在完成了分析之后,对相应的模型进行科学验证,最终验证集的决定系数数值调整为0.950,预测得出的标准偏差数值为1.83。最终的研究结果表明:该试验当中确立起的甲醇物质分析模型基础和常见类型的气象色谱分析法有一致的结构,在试验中能保证试验分析有良好的稳定性以及精密度,这样也就能使得在线类型快速检测技术能白酒当中酒基是实际含量检测中发挥良好作用。 展开更多
关键词 快速检测 近红外 白酒 基酒 甲醇
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A novel near-infrared light responsive 4D printed nanoarchitecture with dynamically and remotely controllable transformation
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作者 Haitao Cui Shida Miao +6 位作者 Timothy Esworthy Se-jun Lee Xuan Zhou Sung Yun Hann Thomas J.Webster Brent T.Harris Lijie Grace Zhang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第6期1381-1388,共8页
Four-dimensional (4D) printing is an emerging and highly innovative additive manufacturing process by which to fabricate pre-designed,self-assembly structures with the ability to transform over time.However,one of the... Four-dimensional (4D) printing is an emerging and highly innovative additive manufacturing process by which to fabricate pre-designed,self-assembly structures with the ability to transform over time.However,one of the critical challenges of 4D printing is the lack of advanced 4D printing systems that not only meet all the essential requirements of shape change but also possess smart,dynamic capabilities to spatiotemporally and instantly control the shape-transformation process.Here,we present a facile 4D printing platform which incorporates nanomaterials into the conventional stimuli-responsive polymer,allowing the 4D printed object to achieve a dynamic and remote controlled,on-time and position shape transformation.A proof-of-concept 4D printed brain model was created using near-infrared light (NIR) responsive nanocomposite to evaluate the capacity for controllable 4D transformation,and the feasibility of photothermal stimulation for modulating neural stem cell behaviors.This novel 4D printing strategy can not only be used to create dynamic 3D patterned biological structures that can spatiotemporally control their shapes or behaviors of transformation under a human benign stimulus (NIR),but can also provide a potential method for building complex self-morphing objects for widespread applications. 展开更多
关键词 NEAR-INFRARED light RESPONSIVE four-dimensional (4D) PRINTING dynamically and remotely CONTROLLABLE graphene BRAIN NEURAL stem cell
基于微型近红外光谱传感器的液体肥组分检测仪研制 预览
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作者 王博 《仪器仪表用户》 2019年第6期6-10,共5页
为快速检测液体肥中的组分含量,本研究提出了一种基于新型的微机电(MEMS)近红外传感器的液体肥近红外检测器,并将其设计成便携式杯型光谱仪结构,使用透射式的方法对液体组分进行检测。该设计的硬件电路主要可以分为:光源及其驱动模块、... 为快速检测液体肥中的组分含量,本研究提出了一种基于新型的微机电(MEMS)近红外传感器的液体肥近红外检测器,并将其设计成便携式杯型光谱仪结构,使用透射式的方法对液体组分进行检测。该设计的硬件电路主要可以分为:光源及其驱动模块、传感器升压控制模块、探测信号I/V运放模块、温度读取模块和AD转换模块。选择使用较小封装的贴片式器件,减小传感器驱动电路的体积。对系统进行了稳定性测试,各波长点的相对标准差基本稳定在0.1%以下,系统较为稳定。使用磷酸氢二铵来配制液体肥溶液进行了检测和建模分析,模型相关系数(R2)为0.942564,交叉验证均方根误差(RMSECV)为1.386777,取得了较好的建模结果。结果证明,该型近红外光谱分析仪系统稳定,可以用来对液体肥组分进行检测。 展开更多
关键词 MEMS 近红外 便携式
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基于功能性近红外光谱技术观察针刺对创伤后应激障碍大鼠脑部血氧浓度的影响
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作者 张彦峰 韩雅迪 +2 位作者 赵中亭 严兴科 杨燕萍 《针灸推拿医学:英文版》 CSCD 2019年第1期9-15,共7页
目的:基于功能近红外光谱技术(fNIRS)观察针刺对创伤后应激障碍(PTSD)模型大鼠脑部血氧浓度的影响,揭示针刺干预PTSD的脑功能机制。方法:将60只Sprague-Dawley(SD)大鼠随机分为空白组、模型组、抓取组、帕罗西汀组和针刺组,每组12只。... 目的:基于功能近红外光谱技术(fNIRS)观察针刺对创伤后应激障碍(PTSD)模型大鼠脑部血氧浓度的影响,揭示针刺干预PTSD的脑功能机制。方法:将60只Sprague-Dawley(SD)大鼠随机分为空白组、模型组、抓取组、帕罗西汀组和针刺组,每组12只。除空白组外,其余各组大鼠均以电击幽闭法复制PTSD动物模型,模型复制共7d。于应激造模前1h,各组接受相应干预:空白组和模型组不接受任何干预,抓取组接受抓取固定,帕罗西汀组接受盐酸帕罗西汀溶液灌胃,针刺组接受针刺治疗,6d为1个疗程,连续干预2个疗程,共计12d。造模结束后,各治疗组连续治疗5d后利用fNIRS系统采集并记录各组大鼠相关脑区组织氧合血红蛋白(HbO2)>脱氧血红蛋白(d-Hb)和总血红蛋白(t-Hb)浓度的变化情况,并进行脑功能评估。结果:干预结束后,与空白组比较,模型组和抓取组大鼠HbO2浓度显著升高,d-Hb浓度显著降低,t-Hb浓度显著升高,差异均具有统计学意义(均P<0.01);与模型组比较,抓取组大鼠HbO2.d-Hb和t-Hb浓度均无明显变化(均P>0.05);与抓取组比较,帕罗西汀组和针刺组大鼠HbO2浓度显著降低,d-Hb浓度显著升高,t-Hb浓度显著降低,差异均具有统计学意义(均P<0.05);帕罗西汀组与针刺组的HbO2> d-Hb和t-Hb浓度均无统计学差异(均P>0.05)。结论:针刺对PTSD模型大鼠脑区血氧浓度有良性的调节作用,这可能是针刺干预PTSD的重要脑功能机制。 展开更多
关键词 针刺疗法 百会 神门 内关 太冲 应激障碍 创伤后 光谱 近红外 大鼠
pH-sensitive and biodegradable charge-transfer nanocomplex for second near-infrared photoacoustic tumor imaging
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作者 Zhimin Wang Paul Kumar Upputuri +11 位作者 Xu Zhen Ruochong Zhang Yuyan Jiang Xiangzhao Ai Zhijun Zhang Ming Hu Zhenyu Meng Yunpeng Lu Yuanjing Zheng Kanyi Pu Manojit Pramanik Bengang Xing 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第1期49-55,共7页
The emerging technique of photoacoustic imaging,especially in the near infra-red(NIR)window,permits high resolution,deep-penetration,clinically reliable sensing.However,few contrast agents are available that can speci... The emerging technique of photoacoustic imaging,especially in the near infra-red(NIR)window,permits high resolution,deep-penetration,clinically reliable sensing.However,few contrast agents are available that can specifically respond to intricate biological environments,and which are biodegradable and biocompatible.Herein,we in troduce a new class of pH-sensitive orga nic photoacoustic con trast age nt that operates in the second NIR window(NIR-II,960-1,700 nm),which is derived from the self-assembled charge-transfer nanocomplex(CTN)by 3,3',5,5'-tetramethylbenzidine(TMB)and its dication structure(TMB++).The unique NIR-ll-responsive CTN can specifically respond to pH change in the physiological range and allows noninvasive and sensitive visualization of the tumor acidic microenvironment(e.g.at pH5)in mice with higher signal-to-noise ratio.The CTN is biodegradable under physiological conditions(e.g.pH 7.4),which alleviates the biosafety concern of nan oparticle accumulati on in vivo.These results clearly show the pote ntial of the TMB/TMB++-based CTN as a promisi ng pH-activated and biodegradable molecular probe for specific tumor photoacoustic imaging in the NIR-II region. 展开更多
关键词 CHARGE-TRANSFER nanocomplex SECOND NEAR-INFRARED window PHOTOACOUSTIC imaging PH-SENSITIVE BIODEGRADABLE tumor acidic microenvironment
柚子皮果胶快速测定的高光谱成像系统
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作者 陈华舟 辜洁 +2 位作者 许丽莉 陈安 唐国强 《分析试验室》 CAS CSCD 北大核心 2019年第4期389-394,共6页
利用高光谱成像技术测定了柚子皮果胶含量,研究高光谱定量分析中不同系统参数对校正模型的影响。利用推扫式图像扫描部件采集柚子果皮切片样本的近红外高光谱数据,使用多变量计量方法建立定量模型并评估预测效果。针对在不同光源强度、... 利用高光谱成像技术测定了柚子皮果胶含量,研究高光谱定量分析中不同系统参数对校正模型的影响。利用推扫式图像扫描部件采集柚子果皮切片样本的近红外高光谱数据,使用多变量计量方法建立定量模型并评估预测效果。针对在不同光源强度、不同镜片焦距、有无测量背景的情况下获取数据完成建模分析,比较不同系统参数对建模效果的影响。建立多变量高光谱成像分析的定量模型,融合不同的预处理方法实现模型优化,能够得到良好的预测结果,验证了高光谱成像分析技术在农作物质量检测中的应用能力。所做的系统参数性能测试对比方案有望推广应用于其他光谱分析过程中,便于为不同的待测对象选择优化的建模参数,对于在线无人机高光谱遥感数据采集的系统设计具有一定参考价值。 展开更多
关键词 高光谱成像 柚子皮果胶 近红外 推扫式扫描 定量分析
基于NIR的白酒酿酒高粱中关键指标的定量分析
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作者 买书魁 杨洋 +5 位作者 赵小波 李宗朋 李子文 盛晓慧 陈红光 周军 《食品科技》 CAS 北大核心 2019年第2期301-307,共7页
文章基于近红外光谱分析技术(NIR)对酿酒高粱中支链淀粉和直链淀粉含量进行定量分析。采用无信息变量消除法(UVE)、无信息变量消除法结合遗传算法(UVE-GA)、无信息变量消除法结合连续投影算法(UVE-SPA)筛选建模特征波长,并结合偏最小二... 文章基于近红外光谱分析技术(NIR)对酿酒高粱中支链淀粉和直链淀粉含量进行定量分析。采用无信息变量消除法(UVE)、无信息变量消除法结合遗传算法(UVE-GA)、无信息变量消除法结合连续投影算法(UVE-SPA)筛选建模特征波长,并结合偏最小二乘法(PLS)建立酿酒高粱中支链淀粉和直链淀粉定量分析模型。所建立的模型结果表明,上述3种波长筛选方法对模型均有一定程度的优化效果,其中无信息变量消除法结合遗传算法(UVE-GA)光谱波长筛选的方法得到的效果最佳,所建立的支链淀粉和直链淀粉模型的决定系数(R~2)分别为0.9523和0.9417,预测均方根误差(RMSEP)分别为1.2845和0.0901,相对分析误差(RPD)分别为12.1和34.18,模型的精确度和鲁棒性均有所提高,为现代白酒企业快速、简便、准确地测定酿酒原料高粱中直链淀粉和支链淀粉含量提供了科学的参考。 展开更多
关键词 近红外 波长筛选 高粱 支链淀粉 直链淀粉
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