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基于FTIR的黄芪药材质量评价研究
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作者 郝彩琴 周莹 +1 位作者 刘明嘉 孙国祥 《中南药学》 CAS 2024年第5期1329-1333,共5页
目的 建立黄芪药材的红外原始指纹图谱与量子指纹图谱,为其质量控制提供参考。方法 采用傅里叶变换红外光谱仪采集35批黄芪药材的红外指纹图谱,经数据处理建立黄芪的红外量子指纹图谱,采用系统指纹定量法以及t检验比较两种指纹图谱是否... 目的 建立黄芪药材的红外原始指纹图谱与量子指纹图谱,为其质量控制提供参考。方法 采用傅里叶变换红外光谱仪采集35批黄芪药材的红外指纹图谱,经数据处理建立黄芪的红外量子指纹图谱,采用系统指纹定量法以及t检验比较两种指纹图谱是否存在差异,并对量子指纹图谱的共有量子峰面积进行系统聚类分析。结果 黄芪药材的红外指纹图谱与量子指纹图谱间并不存在显著性差异,系统指纹定量法将35批黄芪分为8个质量等级,系统聚类分析表明35批黄芪的质量可聚为两类。结论 红外量子指纹图谱能够提供大量特征信息,系统指纹定量法能够全面、准确、直观地将黄芪药材分为8个质量等级,两者结合可以实现对黄芪等中药材质量的全面评价。 展开更多
关键词 黄芪 傅里叶变换红外光谱 量子指纹图谱 系统指纹定量法
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基于Zeta电位和FTIR的中高阶煤与天然焦表面电性研究
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作者 耿恒毅 翟晓荣 +3 位作者 胡广青 刘伟 罗卉卉 徐瑞瑞 《中国煤炭地质》 2024年第8期1-8,25,共9页
通过对中高阶煤与天然焦表面电性的研究,可为揭示煤与天然焦电磁辐射机理,判断矿物可浮性和实现不同矿物分离提供基础。为深入了解中高阶煤与天然焦表面电性的差异,分析煤与天然焦表面官能团组成的差异,采用Zeta电位与FTIR分析方法对样... 通过对中高阶煤与天然焦表面电性的研究,可为揭示煤与天然焦电磁辐射机理,判断矿物可浮性和实现不同矿物分离提供基础。为深入了解中高阶煤与天然焦表面电性的差异,分析煤与天然焦表面官能团组成的差异,采用Zeta电位与FTIR分析方法对样品的表面特性进行综合分析,研究其表面电性与主要官能团的耦合关系。结果表明:①煤样的Zeta电位总体为负,天然焦样品的Zeta电位为正,同时随着变质程度的升高,样品表面负电官能团减少,Zeta电位增大;②脱灰后,样品表面负电官能团被破坏,煤与天然焦的Zeta电位均为正,且随着煤变质程度的增加,Zeta电位值减小;③羟基、COOH、C=O是影响Zeta电位的主要官能团,其中,C=O对Zeta电位的影响大于COOH;羟基-π是羟基结构中影响Zeta电位的主要官能团。研究成果为进一步探究煤与天然焦电磁辐射机理与浮选性提供基础。 展开更多
关键词 中高阶煤 天然焦 ZETA电位 ftir 官能团
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环保绝缘介质C_(6)F_(12)O混合气体FTIR检测技术研究
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作者 KWAME B B 王毅 +3 位作者 田双双 张晓星 黄佳辰 邹怡 《高压电器》 CAS CSCD 北大核心 2024年第9期126-134,共9页
环保绝缘介质C_(6)F_(12)O混合气体具有应用于中低压设备的潜力,因此C_(6)F_(12)O混合气体检测技术的研究具有非常重要的现实意义。文中基于红外吸收光谱提出了C_(6)F_(12)O混合气体定性定量检测技术。基于密度泛函理论,对C_(6)F_(12)O... 环保绝缘介质C_(6)F_(12)O混合气体具有应用于中低压设备的潜力,因此C_(6)F_(12)O混合气体检测技术的研究具有非常重要的现实意义。文中基于红外吸收光谱提出了C_(6)F_(12)O混合气体定性定量检测技术。基于密度泛函理论,对C_(6)F_(12)O分子进行结构优化,仿真计算其振动频谱,与实验检测红外光谱进行对比。对体积分数标定模型的波段和特征量的选取进行了详细的研究,提出C_(6)F_(12)O混合气体相关绝缘设备的混合比和微量体积分数检测方案。结果表明,红外光谱的仿真结果与实验结果具有较好的一致性;不同体积分数的吸收峰有很好的线性关系,利用峰值作为特征值比峰面积建立的体积分数标定模型准确性和稳定性强。混合比检测时,以3 500~3 567 cm^(-1)波段的峰值作特征量建立模型的拟合度为0.999 57,检测误差在2%以内;微量检测时,以1 750~1 820 cm^(-1)波段的峰值作特征量建立模型的拟合度高达0.999 97,检测误差小于3.8%,建立的体积分数标定模型的稳定性、准确性较好。文中研究结果提供实验和仿真的C_(6)F_(12)O红外光谱信息,为C_(6)F_(12)O型气体绝缘设备提供FTIR检测技术,为C_(6)F_(12)O混合气体绝缘设备的混合比和微量体积分数检测提供了重要的理论支撑。 展开更多
关键词 C_(6)F_(12)O混合气体 红外光谱 ftir 混合比检测 微量检测
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Assessment of portable FTIR and Raman spectroscopy for the detection of 2,3-dimethyl-2,3-dinitrobutane(DMDNB)in plastic explosives
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作者 Jacky Cailes Robert Dunsmore Kathryn L.Linge 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期11-18,共8页
The Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of manufacture.However,to-date,laboratory testi... The Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of manufacture.However,to-date,laboratory testing remains the internationally accepted practice for identifying and quantifying the taggants stipulated in the Convention.In this project,portable FTIR and Raman instruments were tested for their ability to detect 2,3-dimethyl-2,3-dinitrobutane(DMDNB),the chemical marker incorporated in plastic explosives that are manufactured within Australia.While both FTIR and Raman instruments detected solid DMDNB(98%purity),field analysis of plastic explosives at an Australian Defence establishment showed that both FTIR and Raman spectra were matched the relevant explosive(RDX or PETN),rather than the DMDNB taggant.For all three plastic explosives tested,the concentration of DMDNB was measured by SPME-GC-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipulated by the Marplex Convention.Additional testing with a plastic explosive analogue confirmed that the minor absorption peaks that would characterize low concentrations of DMDNB were masked by absorption bands from other compounds within the solid.Thus,while both FTIR and Raman spectroscopy are suitable for detection of plastic explosives,neither rely on the presence of DMDNB for detection.It is likely that similar results would be found for other taggants stipulated by the Marplex Convention,given they are also present in concentrations less than 1%. 展开更多
关键词 Explosive ICAO taggants 2 3-Dimethyl-2 3-dinitrobutane(DMDNB) Fourier transform infrared(ftir) Raman
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FTIR结合ELM对黑果腺肋花楸黄酮、多糖含量快速预测 被引量:1
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作者 杨承恩 李萌 +3 位作者 卢秋宇 王金玲 李雨婷 苏玲 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第1期62-68,共7页
黑果腺肋花楸是继蓝莓后的又一小浆果,因其黄酮含量高于蓝莓受到关注,已获进入新资源食品名单,并在饮料行业中使用。黑果腺肋花楸黄酮、多糖是其果汁及果渣中的主要生物活性成分,也是影响其品质的重要因素。以中红外光谱技术结合化学计... 黑果腺肋花楸是继蓝莓后的又一小浆果,因其黄酮含量高于蓝莓受到关注,已获进入新资源食品名单,并在饮料行业中使用。黑果腺肋花楸黄酮、多糖是其果汁及果渣中的主要生物活性成分,也是影响其品质的重要因素。以中红外光谱技术结合化学计量学方法对黑果腺肋花楸黄酮、多糖含量进行预测,为建立简便、快捷的黑果腺肋花楸产品质量检测方法提供基础。采集15个产区共750份黑果腺肋花楸红外光谱数据,测量每份样品黄酮、多糖含量,采用K-S样本划分法按4∶1的比例将样本划分为校正集和验证集,并对分组后的光谱信息进行多元散射校正(MSC)、标准正态化(SNV)、平滑(SG)、一阶导数(FD)、二阶导数(SD)等光谱预处理,与原始光谱进行极限学习机(ELM)建模预测效果对比,确定最佳光谱预处理方法。采用竞争性自适应重加权算法(CARS)和连续投影算法(SPA)进行黑果腺肋花楸黄酮、多糖特征光谱波段选取,将2种方法选取的光谱数据结合偏最小二乘回归法(PLS)、极限学习机(ELM)、支持向量机(SVM)进行建模对比,选出预测效果最佳的算法模型。结果表明,7种光谱预处理方法中,MSC对原始光谱的处理效果最佳,在此处理下黄酮含量预测模型RPD值为6.2017,多糖含量预测模型RPD值为5.4473,预测模型的误差显著下降。经CARS、SPA提取特征光谱后,进行3种算法的建模结果对比,确定CARS-ELM为效果最佳的含量预测模型,其中黄酮含量预测模型的R_(C)为0.9972,RMSEC为0.0175,R_(P)为0.9912,RMSEP为0.0311,RPD为10.6315;而多糖含量预测模型中的R_(C)为0.9965,RMSEC为0.0173,R_(P)为0.9867,RMSEP为0.0337,RPD为8.6647。中红外光谱结合化学计量学方法,尤其是CARS-ELM模型能够更准确地对黑果腺肋花楸黄酮、多糖含量进行预测,此方法的开发为黑果腺肋花楸质量评价提供了快速、简便的方法。 展开更多
关键词 黑果腺肋花楸 中红外光谱 黄酮 多糖 极限学习机
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利用ATR-FTIR研究脂质纳米粒的鼻黏液渗透性
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作者 王健敏 李雪梅 +3 位作者 马士超 李志勇 唐华东 马凤森 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第4期1052-1060,共9页
鼻黏液是影响疫苗和药物经鼻吸收的首要屏障。由于干扰因素复杂多变,在体评价黏液渗透性较难实施,多采用体外评价。现有的药物鼻黏液渗透性检测方法如细胞模型法、多粒子示踪技术等,存在细胞培养周期长、操作繁琐、成本高、可获得信息... 鼻黏液是影响疫苗和药物经鼻吸收的首要屏障。由于干扰因素复杂多变,在体评价黏液渗透性较难实施,多采用体外评价。现有的药物鼻黏液渗透性检测方法如细胞模型法、多粒子示踪技术等,存在细胞培养周期长、操作繁琐、成本高、可获得信息少且需要进行荧光标记等不足,对鼻黏膜制剂的体外评价具有很大的局限性,因此迫切需要建立一种快速、简便、灵敏的鼻黏膜制剂黏液渗透性评价方法。基于衰减全反射-傅里叶红外光谱(ATR-FTIR)对药物结构以及粘蛋白二级结构变化的敏感性,利用其对不同性质(粒径与电荷)脂质体的鼻黏液渗透性进行研究,通过FTIR图谱分析不同脂质纳米粒与黏液中粘蛋白的相互作用,建立了鼻黏膜制剂黏液渗透性的体外评价方法。方法学研究表明,对于聚乙二醇10000(PEG10000)、壳聚糖、海藻酸钠脂质体,该方法线性关系分别为Y=2.3866X+2.154、Y=1.8703X+0.2789、Y=1.13014X+0.0609,线性相关系数分别为0.9958、0.9945、0.9909,精密度RSD值分别为0.62%、0.73%、0.95%;重复性试验中RSD值分别为0.83%、0.97%、0.88%,说明该方法线性关系良好、精密度高、重复性好,可用于体外评价药物制剂在黏液中的渗透性。研究结果表明,利用ATR-FTIR在不同时间内扫描样品可得到不同脂质体制剂样品的强度增加的吸收带。对于不同粒径PEG脂质体而言,粒径越小其黏液渗透性越强;对于不同电荷脂质体而言,壳聚糖脂质体黏液渗透性最弱,海藻酸钠次之,PEG脂质体黏液渗透性最强。进一步研究表明,不同电荷脂质体黏液渗透性的差异源于其与粘蛋白相互作用,该结论可通过分析粘蛋白酰胺Ⅰ带所包含的各二级结构信息得到。综上,基于ATR-FTIR所建立的体外评价方法灵敏简便,可作为多种不同制剂的鼻黏液渗透性的快速测定,经改进后还可用于药物制剂在其他黏液中的渗透性评价,应用前景广阔。 展开更多
关键词 脂质纳米粒 ATR-ftir光谱 渗透 鼻黏液
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Molecular structure characterization of middle-high rank coal via^(13)C NMR,XPS,and FTIR spectroscopy
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作者 Xiao-ming Ni Jing-shuo Zhang +1 位作者 Xiao-kai Xu Bao-yu Wang 《China Geology》 CAS CSCD 2024年第4期702-713,共12页
Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existen... Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existence of aromatic structure,heteroatom structure and fat structure in coal.MS(materials studio)software was used to optimize and construct a 3D molecular structure model of coal.A method for establishing a coal molecular structure model was formed,which was“determination of key structures in coal,construction of planar molecular structure model,and optimization of three-dimensional molecular structure model”.The structural differences were compared and analyzed.The results show that with the increase of coal rank,the dehydrogenation of cycloalkanes in coal is continuously enhanced,and the content of heteroatoms in the aromatic ring decreases.The heteroatoms and branch chains in the coal are reduced,and the structure is more orderly and tight.The stability of the structure is determined by theπ-πinteraction between the aromatic rings in the nonbonding energy EN.Key Stretching Energy The size of EB determines how tight the structure is.The research results provide a method and reference for the study of the molecular structure of medium and high coal ranks. 展开更多
关键词 Molecular structure model Carbon-13 nuclear magnetic resonance(NMR) X-ray photoelectron spectroscopy(XPS) Fourier transform infrared spectroscopy(ftir) COAL
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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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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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CAEFusion: A New Convolutional Autoencoder-Based Infrared and Visible Light Image Fusion Algorithm 被引量:1
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作者 Chun-Ming Wu Mei-Ling Ren +1 位作者 Jin Lei Zi-Mu Jiang 《Computers, Materials & Continua》 SCIE EI 2024年第8期2857-2872,共16页
To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed... To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed.The region attention module is meant to extract the background feature map based on the distinct properties of the background feature map and the detail feature map.A multi-scale convolution attention module is suggested to enhance the communication of feature information.At the same time,the feature transformation module is introduced to learn more robust feature representations,aiming to preserve the integrity of image information.This study uses three available datasets from TNO,FLIR,and NIR to perform thorough quantitative and qualitative trials with five additional algorithms.The methods are assessed based on four indicators:information entropy(EN),standard deviation(SD),spatial frequency(SF),and average gradient(AG).Object detection experiments were done on the M3FD dataset to further verify the algorithm’s performance in comparison with five other algorithms.The algorithm’s accuracy was evaluated using the mean average precision at a threshold of 0.5(mAP@0.5)index.Comprehensive experimental findings show that CAEFusion performs well in subjective visual and objective evaluation criteria and has promising potential in downstream object detection tasks. 展开更多
关键词 Image fusion deep learning auto-encoder(AE) infrared visible light
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Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect 被引量:1
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作者 CHENG Yun SONG Zhanping +2 位作者 XU Zhiwei YANG Tengtian TIAN Xiaoxu 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1058-1074,共17页
The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and tempora... The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass. 展开更多
关键词 Hard siltstone Failure mechanism Stratification effect infrared radiation characteristic Temporal-damage mechanism DISSIMILATION
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基于TG-FTIR-MS技术的烟叶角质层热解行为研究
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作者 李亚玲 马戎 +7 位作者 丁为 冯文宁 徐波 梁淼 刘玉斌 刘伟 王兵 乔学义 《河南农业科学》 北大核心 2024年第2期171-180,共10页
为探究烟叶角质层热解行为及其在热解过程中气相产物释放规律,采用酶法、化学方法分离烟叶角质层,通过扫描电子显微镜和傅里叶红外光谱仪对其进行表征分析,利用热重-傅里叶红外光谱-质谱(TG-FTIR-MS)联用技术检测角质层的热释放行为和... 为探究烟叶角质层热解行为及其在热解过程中气相产物释放规律,采用酶法、化学方法分离烟叶角质层,通过扫描电子显微镜和傅里叶红外光谱仪对其进行表征分析,利用热重-傅里叶红外光谱-质谱(TG-FTIR-MS)联用技术检测角质层的热释放行为和热解产物。结果表明,采用酶法和化学方法均可分离烟叶角质层,烟叶角质层的热解可分为失水(50~135℃)、快速脱挥发分(135~595℃)和碳化(595~900℃)3个阶段,其热解产生的气体成分主要包括CH_(4)和CO_(2),气态产物多集中在300~600℃温度区间,其中以羧酸类化合物和甲苯居多。苯系物在250℃左右开始产生,在500~540℃温度区间内达到峰值,而尼古丁的生成量则相对较少。 展开更多
关键词 烟叶 角质层 分离 TG-ftir-MS联用 热解 气态产物
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Maillard反应前体物质参与木质素微生物转化产物的FTIR光谱特性
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作者 曾玉萍 王楠 +4 位作者 曹志伟 宋岩 郭洪鹏 邱小成 王帅 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第4期1183-1190,共8页
腐殖质(HS)是由各类前体物质缩聚而成,前体物质是调控HS形成的关键。Maillard反应前体物质能否对木质素转化、HS形成有促进作用有待验证。鉴于此,采用液体摇瓶培养法,以木质素培养液为研究对象,通过添加邻苯二酚、葡萄糖和甘氨酸的单一... 腐殖质(HS)是由各类前体物质缩聚而成,前体物质是调控HS形成的关键。Maillard反应前体物质能否对木质素转化、HS形成有促进作用有待验证。鉴于此,采用液体摇瓶培养法,以木质素培养液为研究对象,通过添加邻苯二酚、葡萄糖和甘氨酸的单一及组合溶液,启动120 d的液体摇瓶培养,采用离心法收集上清液(细胞代谢产物)和沉淀(菌体残留物),分析两者性质并深入研究菌体残留物FTIR的光谱特性,系统评价各前体物质对木质素向HS转化的贡献。结果表明:(1)在木质素培养液中添加甘氨酸,历经液体摇瓶培养更有利于细胞代谢产物有机分子的缩合,使其结构趋于复杂,而邻苯二酚参与的4个处理及单独添加葡萄糖更易促进细胞代谢产物的降解,使其分子结构更加简单。与作为空白对照(CK)的无菌去离子水相比,外源添加Maillard反应前体物质能够促进细胞代谢产物矿化,使总有机碳(total organic carbon,TOC)含量下降,单一添加邻苯二酚能够使细胞代谢产物TOC含量始终高于其他处理;(2)添加Maillard反应前体物质可显著提升木质素微生物转化形成菌体残留物的回收率,单一添加邻苯二酚的菌体残留物回收率提升幅度最大,而邻苯二酚、葡萄糖和甘氨酸三者组合溶液对菌体残留物回收率的提升幅度最小,葡萄糖和甘氨酸的组合溶液使菌体残留物回收率在整个培养期间始终处于最高水平。添加Maillard反应前体物质使菌体残留物TOC含量的增加幅度小于CK,尽管如此,培养结束时,邻苯二酚参与的4个处理、葡萄糖和甘氨酸组合溶液的添加使菌体残留物TOC含量显著高于CK;(3)木质素经微生物转化形成的菌体残留物拥有羟基O—H、不对称脂族—CH_(3)、对称脂族—CH_(2)—、芳香碳C C及多糖类物质,与土壤胡敏酸有着相似的FTIR特征,但其分子缩合度尚无法达到土壤胡敏酸的复杂程度。各处理在完成培养后,菌体残留物中的羟基含量有着不同程度增加,而多糖含量有所下降,单一甘氨酸以及葡萄糖和甘氨酸组合溶液的添加使菌体残留物的脂族化程度提高,而邻苯二酚参与的4个处理及单独添加葡萄糖可使菌体残留物中的芳香碳比例进一步提高。综上,添加Maillard反应前体物质可促进细胞代谢产物矿化,使TOC含量下降、提高菌体残留物回收率,同时使其羟基含量增加、多糖含量降低,不同前体物质对菌体残留物脂族化和芳香化的影响规律不同,邻苯二酚参与的4个处理及单一添加葡萄糖可使菌体残留物中的芳香碳比例提高。 展开更多
关键词 MAILLARD反应 前体物质 木质素 菌体残留物 ftir光谱
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Lightweight Dual‑Functional Segregated Nanocomposite Foams for Integrated Infrared Stealth and Absorption‑Dominant Electromagnetic Interference Shielding
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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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Infrared microspectroscopy beamline BL06B at SSRF
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作者 Te Ji Hua-Chun Zhu +4 位作者 Wei-Wei Peng Jie Wang Hong-Wei Zhao Ai-Guo Li Min Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期10-17,共8页
The infrared microspectroscopy beamline(BL06B) is a phase Ⅱ beamline project at the Shanghai Synchrotron Radiation Facility(SSRF). The construction and optical alignment of BL06B were completed by the end of 2020. By... The infrared microspectroscopy beamline(BL06B) is a phase Ⅱ beamline project at the Shanghai Synchrotron Radiation Facility(SSRF). The construction and optical alignment of BL06B were completed by the end of 2020. By 2021, it became accessible to users. The synchrotron radiation infrared(SRIR) source included edge radiation(ER) and bending magnet radiation(BMR). The extracted angles in the horizontal and vertical directions were 40 and 20 mrad, respectively. The photon flux, spectral resolution, and focused spot size were measured at the BL06B endstation, and the experimental results were consistent with theoretical calculations. SRIR light has a small divergence angle, high brightness, and a wide wavelength range. As a source of IR microscopy, it can easily focus on a diffraction-limited spatial resolution with a high signal-to-noise ratio(SNR). The BL06B endstation can be applied in a wide range of research fields, including materials, chemistry, biology, geophysics, and pharmacology. 展开更多
关键词 Synchrotron radiation infrared beamline infrared microspectroscopy
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Erratum to:Deriving Temporal and Vertical Distributions of Methane in Xianghe Using Ground-based Fourier Transform Infrared and Gas-analyzer
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作者 Denghui JI Minqiang ZHOU +6 位作者 Pucai WANG Yang YANG Ting WANG Xiaoyu SUN Christian HERMANS Bo YAO Gengchen WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期377-377,共1页
“Diurnal variation of CH4 at the surface from spring to winter.The time units are in local time(+8 h UTC).The error bar is 1σfor all the observed hourly mean data within that season at that local time.”in the capti... “Diurnal variation of CH4 at the surface from spring to winter.The time units are in local time(+8 h UTC).The error bar is 1σfor all the observed hourly mean data within that season at that local time.”in the caption of Fig.8 on Page 604 should be“Diurnal variation of CH4 at the surface from spring to winter.The time units are in UTC.The error bar is 1σfor all the observed hourly mean data within that season at that local time.” 展开更多
关键词 WINTER SEASON infrared
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Multifunctional MXene/Carbon Nanotube Janus Film for Electromagnetic Shielding and Infrared Shielding/Detection in Harsh Environments
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作者 Tufail Hassan Aamir Iqbal +14 位作者 Byungkwon Yoo Jun Young Jo Nilufer Cakmakci Shabbir Madad Naqvi Hyerim Kim Sungmin Jung Noushad Hussain Ujala Zafar Soo Yeong Cho Seunghwan Jeong Jaewoo Kim Jung Min Oh Sangwoon Park Youngjin Jeong Chong Min Koo 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期543-560,共18页
Multifunctional,flexible,and robust thin films capable of operating in demanding harsh temperature environments are crucial for various cutting-edge applications.This study presents a multifunctional Janus film integr... Multifunctional,flexible,and robust thin films capable of operating in demanding harsh temperature environments are crucial for various cutting-edge applications.This study presents a multifunctional Janus film integrating highly-crystalline Ti_(3)C_(2)T_(x) MXene and mechanically-robust carbon nanotube(CNT)film through strong hydrogen bonding.The hybrid film not only exhibits high electrical conductivity(4250 S cm^(-1)),but also demonstrates robust mechanical strength and durability in both extremely low and high temperature environments,showing exceptional resistance to thermal shock.This hybrid Janus film of 15μm thickness reveals remarkable multifunctionality,including efficient electromagnetic shielding effectiveness of 72 dB in X band frequency range,excellent infrared(IR)shielding capability with an average emissivity of 0.09(a minimal value of 0.02),superior thermal camouflage performance over a wide temperature range(−1 to 300℃)achieving a notable reduction in the radiated temperature by 243℃ against a background temperature of 300℃,and outstanding IR detection capability characterized by a 44%increase in resistance when exposed to 250 W IR radiation.This multifunctional MXene/CNT Janus film offers a feasible solution for electromagnetic shielding and IR shielding/detection under challenging conditions. 展开更多
关键词 MXene/carbon nanotube Janus film Electromagnetic interference shielding infrared shielding Thermal camouflage infrared detection
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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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