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Near Infrared Spectroscopy (NIRS) Model-Based Prediction for Protein Content in Cowpea
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作者 Kavera Biradar Waltram Ravelombola +1 位作者 Aurora Manley Caroline Ruhl 《American Journal of Plant Sciences》 CAS 2024年第3期145-160,共16页
Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models... Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models to estimate protein content in cowpea. A total of 116 cowpea breeding lines with a wide range of protein contents (19.28 % to 32.04%) were selected to build the model using whole seed and ground seed samples. Partial least-squares discriminant analysis (PLS-DA) regression technique with different pre-treatments (derivatives, standard normal variate, and multiplicative scatter correction) were carried out to develop the protein prediction model. Results showed: 1) spectral plots of both the whole seed and ground seed showed higher spectral scatter at higher wavelengths (>1450 nm), 2) data pre-processing affects prediction accuracy for bot whole seed and ground seed samples, 3) prediction using ground seed samples (0.64 R<sup>2</sup> 0.85) is better than the whole seed (0.33 R<sup>2</sup> 0.78), and 4) the data pre-processing second derivative with standard normal variate has the best prediction (R<sup>2</sup>_whole seed = 0.78, R<sup>2</sup>_ground seed = 0.85). The results will be of interest in cowpea breeding programs aimed at improving total seed protein content. 展开更多
关键词 COWPEA GERMPLASM PROTEIN near-infrared Spectroscopy (nirS) Partial Least Squares (PLS)
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Noninvasive Detection of Cerebral Blood Flow and Blood Oxygen Based on Inductive Sensing Technology and Near Infrared Spectroscopy
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作者 Cheng Zhou Zexiang Lyu +6 位作者 Maoting Zhang Xin Zou Liang Wei Feng Wang Mingxin Qin Jia Xu Jian Sun 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期204-212,共9页
The synchronous monitoring of cerebral blood flow and blood oxygen levels plays a pivotal role in the prevention,diagnosis,and treatment of cerebrovascular diseases.This study introduces a novel noninvasive device uti... The synchronous monitoring of cerebral blood flow and blood oxygen levels plays a pivotal role in the prevention,diagnosis,and treatment of cerebrovascular diseases.This study introduces a novel noninvasive device utilizing inductive sensing and near-infrared spectroscopy technology to facilitate simultaneous monitoring of cerebral blood flow and blood oxygen levels.The device consists of modules for cerebral blood flow monitoring,cerebral blood oxygen monitoring,control,communication,and a host machine.Through experiments conducted on healthy subjects,it was confirmed that the device can effectively achieve synchronous monitoring and recording of cerebral blood flow and blood oxygen signals.The results demonstrate the device’s capability to accurately measure these signals simultaneously.This technology enables dynamic monitoring of cerebral blood flow and blood oxygen signals with potential clinical applications in preventing,diagnosing,treating cerebrovascular diseases while reducing their associated harm. 展开更多
关键词 cerebrovascular disease synchronous monitoring inductive sensing near infrared spec-troscopy(nirS)
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Intense Mid-Infrared Laser Pulse Generated via Flying-Mirror Red-Shifting in Near-Critical-Density Plasmas
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作者 鲁瑜 李东澳 +2 位作者 李倩妮 邵福球 余同普 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期42-46,共5页
Relativistic femtosecond mid-infrared pulses can be generated efficiently by laser interaction with near-criticaldensity plasmas.It is found theoretically and numerically that the radiation pressure of a circularly po... Relativistic femtosecond mid-infrared pulses can be generated efficiently by laser interaction with near-criticaldensity plasmas.It is found theoretically and numerically that the radiation pressure of a circularly polarized laser pulse first compresses the plasma electrons to form a dense flying mirror with a relativistic high speed.The pulse reflected by the mirror is red-shifted to the mid-infrared range.Full three-dimensional simulations demonstrate that the central wavelength of the mid-infrared pulse is tunable from 3µm to 14µm,and the laser energy conversion efficiency can reach as high as 13%.With a 0.5–10 PW incident laser pulse,the generated mid-infrared pulse reaches a peak power of 10–180 TW,which is interesting for various applications in ultrafast and high-field sciences. 展开更多
关键词 MIRROR infrared Pulse
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Rice Variety Classification Based on Optimized Near-Infrared Spectral Classification Model
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作者 YANG Sen WANG Zhenmin +1 位作者 ZHANG Houqing SONG Wenlong 《Rice science》 SCIE CSCD 2024年第1期6-9,I0009-I0012,共8页
Accurate classification of rice variety is essential to ensure the brand value of high-quality rice products.Considering the impact of sample state on modeling optimization algorithms,rice samples after grinding and s... Accurate classification of rice variety is essential to ensure the brand value of high-quality rice products.Considering the impact of sample state on modeling optimization algorithms,rice samples after grinding and sealing were selected.To enhance the accuracy of rice variety classification,we introduced a spectral characteristic wavelength selection method based on adaptive sliding window permutation entropy(ASW-PE). 展开更多
关键词 SEALING infrared GRINDING
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BACNN: Multi-scale feature fusion-based bilinear attention convolutional neural network for wood NIR classification
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作者 Zihao Wan Hong Yang +2 位作者 Jipan Xu Hongbo Mu Dawei Qi 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期202-214,共13页
Effective development and utilization of wood resources is critical.Wood modification research has become an integral dimension of wood science research,however,the similarities between modified wood and original wood... Effective development and utilization of wood resources is critical.Wood modification research has become an integral dimension of wood science research,however,the similarities between modified wood and original wood render it challenging for accurate identification and classification using conventional image classification techniques.So,the development of efficient and accurate wood classification techniques is inevitable.This paper presents a one-dimensional,convolutional neural network(i.e.,BACNN)that combines near-infrared spectroscopy and deep learning techniques to classify poplar,tung,and balsa woods,and PVA,nano-silica-sol and PVA-nano silica sol modified woods of poplar.The results show that BACNN achieves an accuracy of 99.3%on the test set,higher than the 52.9%of the BP neural network and 98.7%of Support Vector Machine compared with traditional machine learning methods and deep learning based methods;it is also higher than the 97.6%of LeNet,98.7%of AlexNet and 99.1%of VGGNet-11.Therefore,the classification method proposed offers potential applications in wood classification,especially with homogeneous modified wood,and it also provides a basis for subsequent wood properties studies. 展开更多
关键词 Wood classification near infrared spectroscopy Bilinear network SE module Anti-noise algorithm
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Application of near-infrared spectroscopy for fast germplasm analysis and classification in multi-environment using intact-seed peanut(Arachis hypogaea L.)
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作者 Fentanesh Chekole Kassie Gilles Chaix +10 位作者 Hermine Bille Ngalle Maguette Seye Coura Fall Hodo-Abalo Tossim Aissatou Sambou Olivier Gibert Fabrice Davrieux Joseph Martin Bell Jean-Francois Rami Daniel Fonceka Joel Romaric Nguepjop 《Oil Crop Science》 CSCD 2024年第2期132-141,共10页
Peanut is a worldwide oilseed crop and the need to assess germplasm in a non-destructive manner is important for seed nutritional breeding.In this study,Near Infrared Spectroscopy(NIRS)was applied to rapidly assess ge... Peanut is a worldwide oilseed crop and the need to assess germplasm in a non-destructive manner is important for seed nutritional breeding.In this study,Near Infrared Spectroscopy(NIRS)was applied to rapidly assess germplasm variability from whole seed of 699 samples,field-collected and assembled in four genetic and environmentbased sets:one set of 300 varieties of a core-collection and three sets of 133 genotypes of an interspecific population,evaluated in three environments in a large spatial scale of two countries,Mbalmayo and Bafia in Cameroon and Nioro in Senegal,under rainfed conditions.NIR elemental spectra were gathered on six subsets of seeds of each sample,after three rotation scans,with a spectral resolution of 16 cm-1over the spectral range of867 nm to 2530 nm.Spectra were then processed by principal component analysis(PCA)coupled with Partial least squares-discriminant analysis(PLS-DA).As results,a huge variability was found between varieties and genotypes for all NIR wavelength within and between environments.The magnitude of genetic variation was particularly observed at 11 relevant wavelengths such as 1723 nm,usually related to oil content and fatty acid composition.PCA yielded the most chemical attributes in three significant PCs(i.e.,eigenvalues>10),which together captured 93%of the total variation,revealing genetic and environment structure of varieties and genotypes into four clusters,corresponding to the four samples sets.The pattern of genetic variability of the interspecific population covers,remarkably half of spectrum of the core-collection,turning out to be the largest.Interestingly,a PLS-DA model was developed and a strong accuracy of 99.6%was achieved for the four sets,aiming to classify each seed sample according to environment origin.The confusion matrix achieved for the two sets of Bafia and Nioro showed 100%of instances classified correctly with 100%at both sensitivity and specificity,confirming that their seed quality was different from each other and all other samples.Overall,NIRS chemometrics is useful to assess and distinguish seeds from different environments and highlights the value of the interspecific population and core-collection,as a source of nutritional diversity,to support the breeding efforts. 展开更多
关键词 GROUNDNUT OILSEED near infrared spectroscopy Germplasm analysis ENVIRONMENT NUTRITIONAL Breeding
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Optical design of a novel near-infrared phase contrast imaging(NI-PCI)diagnostic on the HL-2A tokamak
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作者 徐皓 龚少博 +11 位作者 余羿 许敏 兰涛 王志斌 石中兵 聂林 赵光义 刘灏 周艺轩 袁子豪 肖晨雨 陈坚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期31-37,共7页
The optical design of near-infrared phase contrast imaging(NI-PCI)diagnosis on HL-2A is introduced in this paper.This scheme benefits from the great progress of near-infrared laser technology and is a broadening of tr... The optical design of near-infrared phase contrast imaging(NI-PCI)diagnosis on HL-2A is introduced in this paper.This scheme benefits from the great progress of near-infrared laser technology and is a broadening of traditional phase contrast technology.This diagnostic can work as a keen tool to measure plasma wavenumber spectra by inferring string-integrated plasma density fluctuations.Design of both the front optical path which is the path before the laser transmitting into the tokamak plasma and the rear optics which is the path after the laser passing through the plasma is detailed.The 1550 nm laser is chosen as the probe beam and highprecision optical components are designed to fit the laser beam,in which a phase plate with a 194-nm-deep silver groove is the key.Compared with the conventional 10.6μm laser-based PCI system on HL-2A,NI-PCI significantly overcomes the unwanted phase scintillation effect and promotes the measurement capability of high-wavenumber turbulence with an increased maximal measurable wavenumber from 15 cm^(-1)to 32.6 cm^(-1). 展开更多
关键词 phase contrast imaging near infrared laser plasma laser diagnostic
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Millet Origin Identification Model Based on Near-infrared Spectroscopy
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作者 Penghe LYU Dongfeng YANG 《Agricultural Biotechnology》 2024年第3期31-33,共3页
[Objectives]This study was conducted to clarify the difference of millet from different producing areas in near-infrared spectroscopy(NIRS)modeling.[Methods]Millet samples from six different regions were collected for... [Objectives]This study was conducted to clarify the difference of millet from different producing areas in near-infrared spectroscopy(NIRS)modeling.[Methods]Millet samples from six different regions were collected for NIRS analysis,and an origin identification model based on BP neural network was established.The competitive adaptive reweighted sampling(CARS)algorithm was used to extract characteristic wavelength variables,and a CARS-BP model was established on this basis.Finally,the CARS-BP model was compared with support vector machine(SVM),partial least squares discriminant analysis(PLS)and KNN models.[Results]The characteristic wavelengths were extracted by CARS,and the number of variables was reduced from 1845 to 130.The discrimination accuracy of the CARS-BP model for the samples from six producing areas reached 98.1%,which was better than SVM,PSL and KNN models.[Conclusions]NIRS can quickly and accurately identify the origin of millet,providing a new method and way for the origin identification and quality evaluation of millet. 展开更多
关键词 MILLET Identification of origin CARS-BP model nir
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非侵入性NIRS技术监测rSO2指导颈动脉内膜剥脱术中血压阶梯性升压减少脑缺血发生的研究
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作者 肖罡 郭铭 +2 位作者 黄斌 吴佳隆 凌酉 《中国科技期刊数据库 医药》 2024年第11期072-076,共5页
探讨非侵入性近红外光谱(near-infrared spectroscopy, NIRS)技术监测脑氧饱和度(regional cerebral oxygen saturation,rSO2)指导颈动脉内膜剥脱术(arotid endarterectomy,CEA)阶梯性升压减少脑缺血发生的效果。方法 选择2021年3月至2... 探讨非侵入性近红外光谱(near-infrared spectroscopy, NIRS)技术监测脑氧饱和度(regional cerebral oxygen saturation,rSO2)指导颈动脉内膜剥脱术(arotid endarterectomy,CEA)阶梯性升压减少脑缺血发生的效果。方法 选择2021年3月至2024年3月期间,我院收治的行CEA患者共30例。在手术过程中,运用非侵入性近红外光谱(NIRS)技术来监测脑氧饱和度(rSO2),并据此指导手术过程中的血压阶梯性调整。详细记录了麻醉前(TO)、全麻后(T1)、动脉阻断前即刻(T2)、动脉阻断5分钟后(T3)、解除动脉阻断前即刻(T4)以及解除动脉阻断后5分钟(T5)的双侧区域rSO2数值。同时,也记录了动脉阻断后每升高基础动脉压10%时的双侧区域rSO2数值(t1/t2/t3)。术后,30例研究对象均复查了头颈部CT、CTA或者DSA,术后3天随访,分析并发症情况。结果 (1)动脉阻断前,双侧rSO2无显著差异。阻断后,t检验显示P<0.05。临时阻断解除后,脑氧饱和度恢复正常。配对t检验显示t=-1.136,P>0.05。(2)手术后随访,发现声音嘶哑病例1例,立刻对症处理,患者一天内好转。 在整个随访期间,未再发生缺血性脑卒中及TIA事件。结论 CEA手术中,NIRS监测实时反映脑组织氧合状态。调整血压可维持正常脑氧饱和度,满足需氧量,降低脑缺血风险。 展开更多
关键词 nirS 脑氧饱和度 颈动脉内膜剥脱术 阶梯性升压 脑缺血
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锁阳中19种无机元素的NIR快速测定模型的建立与适宜测定元素筛选
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作者 顾志荣 祁梅 +2 位作者 杨浩 郭燕 葛斌 《中国野生植物资源》 CSCD 2024年第2期46-51,共6页
目的:建立锁阳中19种无机元素含量的近红外光谱(NIR)快速测定模型,筛选适宜采用NIR技术进行测定的元素。方法:采集5个省(区)的82批锁阳样品,采用积分球漫反射方式采集样品的NIR原始光谱,采用电感耦合等离子体-质谱(ICP-MS)法测定Na、K... 目的:建立锁阳中19种无机元素含量的近红外光谱(NIR)快速测定模型,筛选适宜采用NIR技术进行测定的元素。方法:采集5个省(区)的82批锁阳样品,采用积分球漫反射方式采集样品的NIR原始光谱,采用电感耦合等离子体-质谱(ICP-MS)法测定Na、K、Ca、Mg、Fe、Zn、Mn、Co、Sr、Ni、Ag、Ba、Ti、Pb、Cr、Cd、As、Hg、Cu等19种无机元素含量的化学参考值,筛选预处理原始光谱的化学计量学方法,筛选最佳波段及因子数,以偏最小二乘法(PLS)建立NIR定量分析模型。结果:K、Ca、Mg、Mn、Co、Sr、Ti、Cr元素的决定系数R^(2)及交叉验证R^(2)均大于0.9,校正均方差(RMSEC)、预测均方差(RMSEP)及留一法交叉验证均方差(RMSECV)在0.52~2.20之间,模型预测值与真实值之间具有较好的相关性,预测性能较好;Ni、Zn元素的决定系数R^(2)及交叉验证R^(2)在0.8~0.9之间,RMSEC、RMSEP及RMSECV在0.49~1.41之间,预测值与真实值之间的相关性一般;Cu元素的决定系数R^(2)及交叉验证R^(2)在0.7~0.8之间,Na、Fe、Ag、Ba、Pb、Cd、As、Hg元素的决定系数R^(2)及交叉验证R^(2)均小于0.7,此9种元素的RMSEC、RMSEP及RMSECV在1.13~10.75之间,预测值与真实值之间的相关性较差。K、Ca、Mg、Mn、Co、Sr、Ti、Cr等8种元素的模型预测值和真实值之间的相对误差在0.04%~7.62%之间,平均预测回收率在94.12%~108.45%之间,预测值与真实值之间无显著性差异(P>0.05)。结论:锁阳中K、Ca、Mg、Mn、Co、Sr、Ti、Cr元素含量适宜采用NIR技术进行快速测定。 展开更多
关键词 锁阳 无机元素 近红外光谱 偏最小二乘 快速测定
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Functional Nonparametric Predictions in Food Industry Using Near-Infrared Spectroscopy Measurement 被引量:1
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作者 Ibrahim M.Almanjahie Omar Fetitah +1 位作者 Mohammed Kadi Attouch Tawfik Benchikh 《Computers, Materials & Continua》 SCIE EI 2023年第3期6307-6319,共13页
Functional statistics is a new technique for dealing with data thatcan be viewed as curves or images. Parallel to this approach, the Near-InfraredReflectance (NIR) spectroscopymethodology has been used in modern chemi... Functional statistics is a new technique for dealing with data thatcan be viewed as curves or images. Parallel to this approach, the Near-InfraredReflectance (NIR) spectroscopymethodology has been used in modern chemistryas a rapid, low-cost, and exact means of assessing an object’s chemicalproperties. In this research, we investigate the quality of corn and cookiedough by analyzing the spectroscopic technique using certain cutting-edgestatistical models. By analyzing spectral data and applying functional modelsto it, we could predict the chemical components of corn and cookie dough.Kernel Functional Classical Estimation (KFCE), Kernel Functional QuantileEstimation (KFQE), Kernel Functional Expectile Estimation (KFEE),Semi-Partial Linear Functional Classical Estimation (SPLFCE), Semi-PartialLinear Functional Quantile Estimation (SPLFQE), and Semi-Partial LinearFunctional Expectile Estimation (SPLFEE) are models used to accuratelyestimate the different quantities present in Corn and Cookie dough. Theselection of these functional models is based on their ability to constructa forecast region with a high level of confidence. We demonstrate that theconsidered models outperform traditional models such as the partial leastsquaresregression and the principal component regression in terms of predictionaccuracy. Furthermore, we show that the proposed models are morerobust than competing models such as SPLFQE and SPLFEE in the sensethat data heterogeneity has no effect on their efficiency. 展开更多
关键词 Functional statistics nir chemical component kernel estimation
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Near-infrared spectroscopy method for rapid proximate quantitative analysis of nutrient composition in Pacific oyster Crassostrea gigas 被引量:1
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作者 Zhe LI Haigang QI +4 位作者 Ying YU Cong LIU Rihao CONG Li LI Guofan ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期342-351,共10页
Glycogen,amino acids,fatty acids,and other nutrient components affect the flavor and nutritional quality of oysters.Methods based on near-infrared reflectance spectroscopy(NIRS)were developed to rapidly and proximatel... Glycogen,amino acids,fatty acids,and other nutrient components affect the flavor and nutritional quality of oysters.Methods based on near-infrared reflectance spectroscopy(NIRS)were developed to rapidly and proximately determine the nutrient content of the Pacific oyster Crassostreagigas.Samples of C.gigas from 19 costal sites were freeze-dried,ground,and scanned for spectral data collection using a Fourier transform NIR spectrometer(Thermo Fisher Scientific).NIRS models of glycogen and other nutrients were established using partial least squares,multiplication scattering correction first-order derivation,and Norris smoothing.The R_(C) values of the glycogen,fatty acids,amino acids,and taurine NIRS models were 0.9678,0.9312,0.9132,and 0.8928,respectively,and the residual prediction deviation(RPD)values of these components were 3.15,2.16,3.11,and 1.59,respectively,indicating a high correlation between the predicted and observed values,and that the models can be used in practice.The models were used to evaluate the nutrient compositions of 1278 oyster samples.Glycogen content was found to be positively correlated with fatty acids and negatively correlated with amino acids.The glycogen,amino acid,and taurine levels of C.gigas cultured in the subtidal and intertidal zones were also significantly different.This study suggests that C.gigas NIRS models can be a cost-effective alternative to traditional methods for the rapid and proximate analysis of various slaughter traits and may also contribute to future genetic and breeding-related studies in Pacific oysters. 展开更多
关键词 Pacific oyster Crassostrea gigas near-infrared reflectance spectroscopy(nirS) nutrient composition rapid determination
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Prediction of Fiber Composition and Silicificationfor Rice Straw with Near Infrared ReflectanceSpectroscopy (NIRS) Technique 被引量:2
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作者 Valdes E V 《Agricultural Sciences in China》 CAS CSCD 2002年第10期1111-1115,共5页
The silicification of rice straw is a factor that affects the grain production and straw nutritive quality. The procedure of chemical analysis for silicon in straw is, however, time and labor consuming, and slightly p... The silicification of rice straw is a factor that affects the grain production and straw nutritive quality. The procedure of chemical analysis for silicon in straw is, however, time and labor consuming, and slightly poor in accuracy. The study has attempted to apply near infrared reflectance spectroscopy (NIRS) technique as an advanced alternative to predict the fiber composition and silicification in rice straw. Ninety-two samples from different seasons and varieties were collected over the Fujian Province. Their chemical analyses were carried on the aspects of hemicellulose, cellulose, lignin, extractable and non-extractable silicon, and the results were used as a database for NIRS analyses. The prediction model was developed through modified partial least square regression (MPLS) for a calibration program. The factors that may affect the calibration, cross-validation and the prediction for the application of NIRS on rice straw were also discussed. 展开更多
关键词 nirS Rice straw Fiber composition SILICON
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Lightweight Dual‑Functional Segregated Nanocomposite Foams for Integrated Infrared Stealth and Absorption‑Dominant Electromagnetic Interference Shielding 被引量:1
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作者 Zhonglei Ma Ruochu Jiang +8 位作者 Jiayao Jing Songlei Kang Li Ma Kefan Zhang Junxian Li Yu Zhang Jianbin Qin Shuhuan Yun Guangcheng Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期38-55,共18页
Lightweight infrared stealth and absorption-dominant electromagnetic interference(EMI)shielding materials are highly desirable in areas of aerospace,weapons,military and wearable electronics.Herein,lightweight and hig... Lightweight infrared stealth and absorption-dominant electromagnetic interference(EMI)shielding materials are highly desirable in areas of aerospace,weapons,military and wearable electronics.Herein,lightweight and high-efficiency dual-functional segregated nanocomposite foams with microcellular structures are developed for integrated infrared stealth and absorption-dominant EMI shielding via the efficient and scalable supercritical CO_(2)(SC-CO_(2))foaming combined with hydrogen bonding assembly and compression molding strategy.The obtained lightweight segregated nanocomposite foams exhibit superior infrared stealth performances benefitting from the synergistic effect of highly effective thermal insulation and low infrared emissivity,and outstanding absorption-dominant EMI shielding performances attributed to the synchronous construction of microcellular structures and segregated structures.Particularly,the segregated nanocomposite foams present a large radiation temperature reduction of 70.2℃ at the object temperature of 100℃,and a significantly improved EM wave absorptivity/reflectivity(A/R)ratio of 2.15 at an ultralow Ti_(3)C_(2)T_(x) content of 1.7 vol%.Moreover,the segregated nanocomposite foams exhibit outstanding working reliability and stability upon dynamic compression cycles.The results demonstrate that the lightweight and high-efficiency dual-functional segregated nanocomposite foams have excellent potentials for infrared stealth and absorption-dominant EMI shielding applications in aerospace,weapons,military and wearable electronics. 展开更多
关键词 Segregated nanocomposite foams Microcellular structures infrared stealth EMI shielding Low infrared emissivity
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miR⁃138⁃5p靶向Nir1调控胶质瘤细胞的侵袭
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作者 陈萍萍 平勇 +5 位作者 赵一诺 梁粉花 宋佰慧 王玲 李慧玲 孙树艳 《循证医学》 2024年第1期37-43,共7页
目的 探讨miR-138-5p与PYK2 N端结构域相互作用受体1(PYK2 N-terminal domain-interacting receptor 1,Nir1)之间的关系并判断其是否通过与Nir1结合影响胶质瘤的侵袭。方法 比较不同胶质瘤细胞系中miR-138-5p表达水平及其对胶质瘤细胞U... 目的 探讨miR-138-5p与PYK2 N端结构域相互作用受体1(PYK2 N-terminal domain-interacting receptor 1,Nir1)之间的关系并判断其是否通过与Nir1结合影响胶质瘤的侵袭。方法 比较不同胶质瘤细胞系中miR-138-5p表达水平及其对胶质瘤细胞U251和H4中Nir1蛋白的影响、转染后胶质瘤细胞侵袭能力,检测miR-138-5p能否与Nir1靶向结合。结果 低侵袭人胶质瘤H4细胞中miR-138-5p的水平显著高于高侵袭性的胶质瘤U251、LN229和U87细胞(P<0.05);在U251、H4细胞中,miR-138-5p过表达组Nir1蛋白表达量较其对照组(miR-negative control,miR-NC)降低;miR-138-5p抑制组中Nir1蛋白表达量较其对照组(inhibitor NC)升高。然而,miR-138-5p过表达组中Nir1的mRNA水平较其对照组无明显改变(P>0.05)。miR-138-5p过表达组穿过基底膜小孔的U251、H4细胞数明显少于其对照组(P<0.05)。miR-138-5p过表达显著降低Nir1-3’-UTR的荧光素酶活性。结论 胶质瘤细胞中miR-138-5p与Nir1结合,可通过降低Nir1的翻译、减少Nir1蛋白的表达抑制胶质瘤细胞的侵袭能力。 展开更多
关键词 胶质瘤 侵袭 miR⁃138⁃5p nir1
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Fusion SST from Infrared and Microwave Measurement of FY-3D Meteorological Satellite 被引量:1
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作者 张淼 徐娜 陈林 《Journal of Tropical Meteorology》 SCIE 2024年第1期89-96,共8页
Sea surface temperature(SST)is one of the important parameters of global ocean and climate research,which can be retrieved by satellite infrared and passive microwave remote sensing instruments.While satellite infrare... Sea surface temperature(SST)is one of the important parameters of global ocean and climate research,which can be retrieved by satellite infrared and passive microwave remote sensing instruments.While satellite infrared SST offers high spatial resolution,it is limited by cloud cover.On the other hand,passive microwave SST provides all-weather observation but suffers from poor spatial resolution and susceptibility to environmental factors such as rainfall,coastal effects,and high wind speeds.To achieve high-precision,comprehensive,and high-resolution SST data,it is essential to fuse infrared and microwave SST measurements.In this study,data from the Fengyun-3D(FY-3D)medium resolution spectral imager II(MERSI-II)SST and microwave imager(MWRI)SST were fused.Firstly,the accuracy of both MERSIII SST and MWRI SST was verified,and the latter was bilinearly interpolated to match the 5km resolution grid of MERSI SST.After pretreatment and quality control of MERSI SST and MWRI SST,a Piece-Wise Regression method was employed to correct biases in MWRI SST.Subsequently,SST data were selected based on spatial resolution and accuracy within a 3-day window of the analysis date.Finally,an optimal interpolation method was applied to fuse the FY-3D MERSI-II SST and MWRI SST.The results demonstrated a significant improvement in spatial coverage compared to MERSI-II SST and MWRI SST.Furthermore,the fusion SST retained true spatial distribution details and exhibited an accuracy of–0.12±0.74℃compared to OSTIA SST.This study has improved the accuracy of FY satellite fusion SST products in China. 展开更多
关键词 SST data fusion FY3 infrared MICROWAVE
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Infrared and Visible Image Fusion Based on Res2Net-Transformer Automatic Encoding and Decoding 被引量:1
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作者 Chunming Wu Wukai Liu Xin Ma 《Computers, Materials & Continua》 SCIE EI 2024年第4期1441-1461,共21页
A novel image fusion network framework with an autonomous encoder and decoder is suggested to increase thevisual impression of fused images by improving the quality of infrared and visible light picture fusion. The ne... A novel image fusion network framework with an autonomous encoder and decoder is suggested to increase thevisual impression of fused images by improving the quality of infrared and visible light picture fusion. The networkcomprises an encoder module, fusion layer, decoder module, and edge improvementmodule. The encoder moduleutilizes an enhanced Inception module for shallow feature extraction, then combines Res2Net and Transformerto achieve deep-level co-extraction of local and global features from the original picture. An edge enhancementmodule (EEM) is created to extract significant edge features. A modal maximum difference fusion strategy isintroduced to enhance the adaptive representation of information in various regions of the source image, therebyenhancing the contrast of the fused image. The encoder and the EEM module extract features, which are thencombined in the fusion layer to create a fused picture using the decoder. Three datasets were chosen to test thealgorithmproposed in this paper. The results of the experiments demonstrate that the network effectively preservesbackground and detail information in both infrared and visible images, yielding superior outcomes in subjectiveand objective evaluations. 展开更多
关键词 Image fusion Res2Net-Transformer infrared image visible image
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Feasibility study of assessing cotton fiber maturity from near infrared hyperspectral imaging technique
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作者 LIU Yongliang TAO Feifei +1 位作者 YAO Haibo KINCAID Russell 《Journal of Cotton Research》 CAS 2023年第4期266-276,共11页
Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laborat... Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laboratories under a controlled environment.There is an increasing need to measure fiber maturity using low-cost(in general less than $20000)and small portable systems.In this study,a laboratory feasibility was performed to assess the ability of the shortwave infrared hyperspectral imaging(SWIR HSI)technique for determining the conditioned fiber maturity,and as a comparison,a bench-top commercial and expensive(in general greater than $60000)near infrared(NIR)instrument was used.Results Although SWIR HSI and NIR represent different measurement technologies,consistent spectral characteristics were observed between the two instruments when they were used to measure the maturity of the locule fiber samples in seed cotton and of the well-defined fiber samples,respectively.Partial least squares(PLS)models were established using different spectral preprocessing parameters to predict fiber maturity.The high prediction precision was observed by a lower root mean square error of prediction(RMSEP)(<0.046),higher R_(p)^(2)(>0.518),and greater percentage(97.0%)of samples within the 95% agreement range in the entire NIR region(1000-2500 nm)without the moisture band at 1940 nm.Conclusion SWIR HSI has a good potential for assessing cotton fiber maturity in a laboratory environment. 展开更多
关键词 near infrared spectroscopy near infrared hyperspectral imaging Fiber maturity Seed cotton Partial least squares regression
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Near-infrared spectroscopy(NIRS) evaluation and regional analysis of Chinese faba bean(Vicia faba L.) 被引量:4
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作者 Jiaojiao Wang Hao Liu Guixing Ren 《The Crop Journal》 SCIE CAS 2014年第1期28-37,共10页
To analyze the nutritional composition of faba bean(Vicia faba L.) seed, estimation models were developed for protein, starch, oil, and total polyphenol using near infrared spectroscopy(NIRS). Two hundred and forty-fo... To analyze the nutritional composition of faba bean(Vicia faba L.) seed, estimation models were developed for protein, starch, oil, and total polyphenol using near infrared spectroscopy(NIRS). Two hundred and forty-four samples from twelve producing regions were measured in both milled powder and intact seed forms. Partial least squares(PLS) regression was applied for model development. The model based on ground seed powder was generally superior to that based on the intact seed. The optimal seed powder-based models for protein, starch, and total polyphenol had coefficients of correlation(r2) of 0.97, 0.93 and 0.89, respectively. The relationship between nutrient contents and twelve producing areas was determined by two-step cluster analysis. Three distinct groupings were obtained with region-constituent features, i.e., Group 1 of high oil, Group 2 of high protein, and Group 3 of high starch as well as total polyphenol. The clustering accuracy was 79.5%. Moreover, the nutrition contents were affected by seeding date, longitude, latitude, and altitude of plant location. Cluster analysis revealed that the differences in the seed were strongly influenced by geographical factors. 展开更多
关键词 VICIA faba L.nirS TWO-STEP CLUSTER analysis SEED quality GERMPLASM source
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Efficient Electromagnetic Wave Absorption and Thermal Infrared Stealth in PVTMS@MWCNT Nano‑Aerogel via Abundant Nano‑Sized Cavities and Attenuation Interfaces 被引量:1
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作者 Haoyu Ma Maryam Fashandi +5 位作者 Zeineb Ben Rejeb Xin Ming Yingjun Liu Pengjian Gong Guangxian Li Chul B.Park 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期370-383,共14页
Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT... Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work. 展开更多
关键词 Nano-pore size Heterogeneous interface Electromagnetic wave absorption Thermal infrared stealth Nano-aerogel
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