Extraction of the key infrared radiation temperature features concerning stress and crack evolution of loaded rocks

The infrared radiation temperature(IRT)variation concerning stress and crack evolution of rocks is a critical focus in rock mechanics domain and engineering disaster warning.In this paper,a methodology to extract the key IRT features related to stress and crack evolution of loaded rocks is proposed.Specifically,the wavelet denoising and reconstruction in thermal image sequence(WDRTIS)method is employed to eliminate temporal noise in thermal image sequences.Subsequently,the adaptive partition temperature drift correction(APTDC)method is introduced to alleviate temperature drift.On this basis,the spatial noise correction method based on threshold segmentation and adaptive median filtering(OTSU-AMF)is proposed to extract the key IRT features associated with microcracks of loaded rocks.Following temperature drift correction,IRT provides an estimation of the thermoelastic factor in rocks,typically around 5.29×10^(-5) MPa^(-1) for sandstones.Results reveal that the high-temperature concentrated region in cumulative thermal images of crack evolution(TICE)can elucidate the spatiotemporal evolution of localized damage.Additionally,heat dissipation of crack evolution(HDCE)acquired from TICE quantifies the progressive failure process of rocks.The proposed methodology enhances the reliability of IRT monitoring results and provides an innovative approach for conducting research in rock mechanics and monitoring engineering disasters.

Study on the Authenticity of Identification Methods in White Spirit by Infrared Spectrometer

This experiment studies on the used infrared spectroscopy to establish technology methods for liquor identification methods, as well as offers the science data for establishment of the fingerprint in white spirit. The results have shown that using near-infrared spectroscopy analysis of liquor has the obvious features such as strong specificity, good reproducibility, simple operation, and finally confirmed that it is an authentic and ideal method for identification in white spirit.

Infrared modeling and imaging simulation of midcourse ballistic targets based on strap-down platform

An infrared （IR） imaging simulation framework based on the strap-down platform is proposed for midcourse ballistic targets. It overcomes the shortcoming of the existing algorithms, which cannot simulate IR imaging from the entire midcourse process. The proposed framework includes three steps, target characteristic modeling, motion modeling, and imaging modeling. In imaging modeling, the staring focal plane is taken into account due to its wide employment. In order to obtain IR images of high fidelity, especially that the fluctuation of the target signal-to-noise ratio （SNR） is reasonably similar to the actual one, this paper proposes an improved IR imaging simulation method. The proposed method considers two critical factors of the pixel plane, occupy-empty ratio and defect elements, which affect the imaging of targets markedly but are neglected in previous work. Finally, the IR image sequence of high fidelity is obtained. And the correlative parameters of simulation can be set according to the given scene. Thus the generated images can satisfy the needs of algorithms validation for tracking and recognition.

A pixel-level local contrast measure for infrared small target detection

Infrared(IR) small target detection is one of the key technologies of infrared search and track(IRST)systems. Existing methods have some limitations in detection performance, especially when the target size is irregular or the background is complex. In this paper, we propose a pixel-level local contrast measure(PLLCM), which can subdivide small targets and backgrounds at pixel level simultaneously.With pixel-level segmentation, the difference between the target and the background becomes more obvious, which helps to improve the detection performance. First, we design a multiscale sliding window to quickly extract candidate target pixels. Then, a local window based on random walker(RW) is designed for pixel-level target segmentation. After that, PLLCM incorporating probability weights and scale constraints is proposed to accurately measure local contrast and suppress various types of background interference. Finally, an adaptive threshold operation is applied to separate the target from the PLLCM enhanced map. Experimental results show that the proposed method has a higher detection rate and a lower false alarm rate than the baseline algorithms, while achieving a high speed.

Micro-motion dynamics analysis of ballistic targets based on infrared detection

The dynamic characteristics related to micro-motions, such as mechanical vibration or rotation, play an essential role in classifying and recognizing ballistic targets in the midcourse, and recent researches explore ways of extracting the micro-motion features from radar signals of ballistic targets. In this paper, we focus on how to investigate the micro-motion dynamic characteristics of the ballistic targets from the signals based on infrared (IR) detection, which is mainly achieved by analyzing the periodic fluctuation characteristics of the target IR irradiance intensity signatures. Simulation experiments demonstrate that the periodic characteristics of IR signatures can be used to distinguish different micro motion types and estimate related parameters. Consequently, this is possible to determine the micro-motion dynamics of ballistic targets based on IR detection.

Structure and Two-dimensional Correlation Infrared Spectroscopy Study of a New One-dimensional Chain Compound: (4,4’-Hbpy)_3[NaMo_8O_(26)](4,4’- bpy)_2(H_2O)_4 (bpy = Bipydine)

A novel compound, （4,4＇-Hbpy）3[NaMo8O26]（4,4＇-bpy）2（H2O）4 1 （bpy=bipydine）, was synthesized by the hydrothermal method. Single-crystal X-ray diffraction shows that compound 1 belongs to the monoclinic system, space group C2/m with a=19.1921（5）, b=18.6931（6）, c=9.3821（3） A° β=104.8020（11）°, V=3254.22（17）A°^3 C50H51Mo8N10NaO30, Mr=2062.52, Z=2, F（000）=2016, μ=1.591 mm^-1 and Dc=2.105 g/cm^3. The final R=0.0283 and wR=0.0912 for 3118 observed reflections （I〉20（I））. Compound 1 contains the β-[Mo8O26]^4-anion, sodium ion, 4,4＇-bpy and lattice crystalline water molecules. The β-[MosO26] units link the sodium ion to form a chain structure. The infinitechains of [Na（Mo8O26）]^3- blocks are surrounded by protonized 4,4＇-bpy cations, 4,4＇-bpy and lattice crystalline water molecules. The 2D-IR correlation spectroscopy study indicates that the stretching vibrations of Mo=O occur more preferentially due to the thermal effect. The TGA analysis shows that compound 1 has high thermal stability.

Calculation of the infrared frequency and the damping constant (full width at half maximum) for metal organic frameworks

The ρ(NH2) infrared(IR) frequencies and the corresponding full width at half maximum(FWHM) values for(CH3)2 NH2 FeⅢ M Ⅱ(HCOO)6(DMFe M, M = Ni, Zn, Cu, Fe, and Mg) are analyzed at various temperatures by using the experimental data from the literature. For the analysis of the IR frequencies of the ρ(NH2) mode which is associated with the structural phase transitions in those metal structures, the temperature dependence of the mode frequency is assumed as an order parameter and the IR frequencies are calculated by using the molecular field theory. Also, the temperature dependence of the IR frequencies and of the damping constant as calculated from the models of pseudospin(dynamic disorder of dimethylammonium(DMA+) cations)–phonon coupling(PS) and of the energy fluctuation(EF), is fitted to the observed data for the wavenumber and FWHM of the ρ(NH2) IR mode of the niccolites studied here. We find that the observed behavior of the IR frequencies and the FWHM of this mode can be described adequately by the models studied for the crystalline structures of interest. This method of calculating the frequencies(IR and Raman) and FWHM of modes which are responsible for the phase transitions can also be applied to some other metal organic frameworks.

新吲哚菁绿IR-820辅助的近红外荧光成像和光热及协同治疗在肿瘤诊疗中的应用进展

新吲哚菁绿IR-820因其具有强近红外(near-infrared,NIR,750~1700 nm)荧光特性、良好生物相容性、高光热转换效率及稳定性等优势,在NIR发光的有机荧光染料中脱颖而出,被广泛应用于生物医学成像、荧光标记、细胞实时监测、光热治疗等研究领域。为更好地发挥IR-820的生物医学应用价值,研究人员用不同生物化学分子修饰IR-820来增强其荧光及光热特性,制备多种类的荧光纳米粒子,在基础生物医学成像与肿瘤光热治疗方面开展了众多研究。总结了IR-820荧光纳米粒子在近红外荧光成像和通过光热机理及与其他技术协同治疗肿瘤中的应用研究,希望为进一步推进有机荧光染料IR-820在生物医学领域应用和临床转化发展提供参考。

Light-Induced Mid-Infrared Emission of Liquid Carbon Tetrachloride and Benzene

Light-induced infrared emission spectroscopy (LIRES) is a novel technique that permits to receive high-quality spectra in the mid-infrared region. Low-intensity visible light connected to a highly sensitive FTIR spectrometer is more advantageous for studying any samples, including biological samples without any damage. This technique permits obtaining unique information on the molecule structure via vibrational excitation fundamental frequencies, overtones, and combination modes. It also enables a direct observation of vibrational radiation transitions in vibrationally excited molecules as well as the channels of vibration energy redistribution, which is not allowed with any other method. In this work, the LIRES is being tested as a technique for studying of vibrationally-excited molecules of carbon tetrachloride and benzene in the liquid phase. On the other hand, using transparent liquids, we had tried to understand some of the physical phenomena that can drive emission in mid-IR. The characteristics of the infrared emission of both liquid species produced by different wavelength radiation from various types of light systems (100 - watt Xe-lamp and Nd:YAG laser;lambda = 1064 nm (8 mW) and lambda = 532 nm (4 mW)) are presented. We demonstrated that the IR-signal, as well as spectral properties of carbon tetrachloride and benzene, was dependent on the wavelength and power of excitation beam. Results obtained with different light sources show that the visible light produces a nonlinear IR-emission signal in transparent liquids. We believe that the visible light is the source of the nonlinear response and is producing the vibration excitation as well as photostimulated transformations of the molecules possessing the high activity for the nonlinear response.

Deep near infrared light-excited stable synergistic photodynamic and photothermal therapies based on P-IR890 nano-photosensitizer constructed via a non-cyanine dye

The cyanine dyes represented by IR780 can achieve synergistic photodynamic therapy(PDT)and photothermal therapy(PTT)under the stimulation of near-infrared(NIR)light(commonly 808 nm).Unfortunately,the stability of NIR-excited cyanine dyes is not satisfactory.These cyanine dyes can be attacked by self-generated reactive oxygen species(ROS)during PDT processes,resulting in structural damage and rapid degradation,which is fatal for phototherapy.To address this issue,a novel non-cyanine dye(IR890)was elaborately designed and synthesized by our team.The maximum absorption wavelength of IR890 was located in the deep NIR region(ca.890 nm),which was beneficial for further improving tissue penetration depth.Importantly,IR890 exhibited good stability when continuously illuminated by deep NIR light.To improve the hydrophilicity and biocompatibility,the hydrophobic IR890 dye was grafted onto the side chain of hydrophilic polymer(POEGMA-b-PGMA-g-C≡CH)via click chemistry.Then,the synthesized POEGMA-b-PGMA-g-IR890 amphiphilic polymerwas utilized to prepare P-IR890 nano-photosensitizer via self-assembly method.Under irradiation with deep NIR light(850 nm,0.5 W/cm^(2),10 min),the dye degradation rate of P-IR890 was less than 5%.However,IR780 was almost completely degraded with the same light output power density and irradiation duration.In addition,P-IR890 could stably generate a large number of ROS and heat at the same time.It was rarely reported that the stable synergistic combination therapy of PDT and PTT could be efficiently performed by a single photosensitizer via irradiation with deep NIR light.P-IR890 exhibited favorable anti-tumor outcomes through apoptosis pathway.Therefore,the P-IR890 could provide a new insight into the design of photosensitizers and new opportunities for synergistic combination therapy of PDT and PTT.

氟诺哌齐结构和性质的密度泛函理论研究

氟诺哌齐是一种新型的抗阿尔茨海默病临床候选药物,目前尚处于临床试验阶段;对氟诺哌齐进行密度泛函理论研究,有助于揭示其分子的性质和功能.在B3LYP/6-311+G(d,p)基组水平上,采用密度泛函理论(DFT)的方法优化氟诺哌齐的分子结构;在相同基组水平下经过谐振频率分析,证实了12种分子构象的稳定结构,并确定了优势构型为DC20-1.根据Marcus理论,对其重组能进行模拟计算,得出氟诺哌齐分子不具备运输性质.通过前线轨道(FMO)分析,发现氟诺哌齐分子具有一定的电子跃迁能力和分子内反应活性,活性反应位点为C15、O28、C23和O26.根据红外光谱、紫外-可见吸收光谱模拟计算结果,对谱图数据进行了讨论分析,研究结果可作为氟诺哌齐表征和鉴别的参考依据.

硬脂酸亚甲基面外弯曲振动变温FT-IR光谱研究

在293～393 K温度范围内,分别采用傅里叶红外光谱、二阶导数红外光谱、四阶导数红外光谱及去卷积红外光谱测定硬脂酸亚甲基面外弯曲振动(ωCH2),来进一步研究温度对于硬脂酸脂肪链构象的影响。实验发现:在1180～1320cm-1范围内,硬脂酸ωCH2存在"第一特征谱带"和未见文献报道的"第二特征谱带"。硬脂酸脂肪链由全反式有序构象到无序构象的改变的临界温度为353～358K,并进一步研究了温度对于硬脂酸ωCH2红外吸收峰强度的影响。

FT-IR光谱法测定籼米淀粉回生

研究了傅立叶变换红外(FT-IR)光谱法快速检测籼米淀粉回生,发现FT-IR光谱中一些特征振动模式的相对强度(与761.76 cm-1处峰高的比值)会随淀粉回生程度的增加而降低.振动模式包括:3 415 cm-1附近的O—H伸缩振动、2 927.46 cm-1处的CH2伸缩振动、1 155.17 cm-1处C—O和C—C伸缩振动、1 081.89 cm-1处的C—O—H弯曲振动、1 043.32,1 020.18和998.96 cm-1处未确定的振动模式、609.41和578.55 cm-1处的吡喃环骨架振动模式.将以上这些特征振动模式的相对强度倒数与DSC回生焓值进行相关性分析可知:1 081.89,1 043.32,1 020.18,609.41和578.55 cm-1处吸收峰的相关系数均能达到0.9以上,因此可将这5种FT-IR振动模式的相对强度变化作为定量指示淀粉回生程度的多重指标.

HJ-1B/IRS热红外数据反演太湖水温的方法比较

太湖是我国典型的富营养化湖泊,水温是影响太湖藻类生长的重要环境因子之一,我国环境减灾卫星HJ-1B搭载的红外多光谱相机IRS对太湖水温动态遥感监测具有较大的性能优势.利用6景过境太湖的IRS热红外遥感影像,分别采用单通道普适性算法、辐射传输模型法和单窗算法反演太湖水温,并与实测水温和同期的TERRA/MODIS温度产品进行对比.结果表明,普适性单通道算法反演水温偏高,而辐射传输模型法和单窗算法则偏低;3种算法反演水温的均方根误差在1.001 K以内,单窗算法反演精度最高,其次是辐射传输模型法,再次为普适性单通道算法,而同期MODIS温度产品的均方根误差为1.507 K.3种算法从IRS热红外数据反演的水温直方图均呈正峰态、尖峰状态分布,反演结果能真实地反映太湖水温的空间分布特征.本研究对只有单个热红外通道的卫星传感器开展内陆水体水温遥感监测具有一定的参考意义.

固/液界面原位红外显微镜和步进扫描时间分辨FTIR反射光谱及其在纳米材料科学中的应用

结合红外显微镜和步进扫描FTIR光谱仪 ,发展了固 /液界面电化学原位显微镜红外反射光谱和步进扫描快速时间分辨FTIR反射光谱 ,并应用于纳米材料特殊性能和电化学反应动力学的研究。研制纳米结构Pt微电极 ,获得CO吸附的红外特征随纳米结构和纳米尺度变化的原位显微镜红外谱图。利用纳米结构Pt微电极的异常红外效应 ,显著提高电化学原位红外反射光谱的灵敏度 ,获得分辨率达 5 0 μs的步进扫描时间分辨光谱。不仅发展了固 /液界面显微镜原位红外反射光谱新方法 ,并且拓展了电化学原位红外反射光谱在纳米材料科学研究中的应用。

FT-IR在研究蛋白质二级结构中的应用

目的研究蛋白质的二级结构。方法介绍蛋白质二级结构定量分析方法,综述FT-IR在蛋白质二级结构研究中的应用进展情况,并对其应用前景进行了展望。结果FT-IR分析技术是一种高效、快速研究蛋白质结构的现代分析技术。结论为了获得更精确的信息,须将FT-IR技术与生物样品的处理与实验设计相结合。

新型染料IR-808靶向肿瘤近红外荧光成像的体内研究

目的探讨近红外荧光染料IR-808在移植瘤动物模型中特异性的肿瘤靶向示踪作用。方法建立人肺癌细胞系NCI-H460、结肠癌细胞系HCT-116及鼠源肝癌细胞系Hepa 1-6皮下移植瘤裸小鼠模型,未接种癌细胞的裸小鼠作对照。尾静脉注射同等剂量染料IR-808,分别在不同时间点对裸小鼠正常组织及肿瘤组织进行近红外荧光成像,追踪染料在裸小鼠体内的分布,评价其肿瘤靶向作用。结果在未接种的裸小鼠体内,IR-808染料首先在肝脏、心脏聚集,随后信号减弱,48h后基本代谢排出体外;在荷瘤裸小鼠模型体内,IR-808染料注入24h后开始靶向肿瘤,72h后荧光信号仍很稳定;取荷瘤裸小鼠组织进行近红外荧光成像,发现仅肿瘤组织有信号,其他组织无信号。全部实验小鼠状态良好,未见明显毒性反应。结论近红外荧光染料IR-808能特异性靶向肿瘤成像,且信号稳定,无明显毒性,具有重要的应用前景。

船舶柴油机在用润滑油FT-IR光谱特征信息提取与应用

对2台船舶主柴油机润滑油进行为期1年的监测,共采集正常衰变的油样32个,另选取实际监测中发现典型的故障油样12个,应用Avatar 360型FT-IR光谱油品分析系统对上述油样进行分析。以获取的32个油样FT-IR光谱信息为研究对象,采用主成分分析法对信息进行了提取,使原始信息从5维降低至1维,建立了特征信息描述模型,将指标界限值评价法与主成分分析法相结合,通过主成分得分计算,按照正常、警告和换油3种状态,将油样进行有效的分类,实现了润滑油油品状态的评价。对获取的12个典型故障油样FT-IR光谱和原子发射光谱数据分析,表明FT-IR光谱信息能有效监测和诊断润滑油进水和燃油稀释2类故障现象,同时从微观上揭示2类现象对润滑油性能的影响,并能早于原子发射光谱发现设备摩擦学系统故障源。

IR-CRT与微镜型红外场景产生器应用特性分析

利用红外场景产生器技术进行复杂红外成像系统的半实物仿真实验已成为趋势。报道了国内使用较多的IR-CRT与微镜两种红外场景产生器的情况及现状。介绍了它们与不同类型红外成像系统的图像匹配情况,对分辨率、对比度、灰度级等主要图像性能参数及在不同工作波段的差异进行了分析对比。分析了两种红外场景产生器技术方案的应用范围及未来发展方向。

基于FT-IR及二维相关分析的SBS超热老化机理

通过原位动态红外光谱分析技术,发现苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)在250℃的超热老化过程中,SBS分子中的C=C双键受到氧原子的进攻,其吸收峰随老化时间延长呈明显降低的趋势,生成羰基、羟基和醚键等一系列的氧化产物,并且老化时间越长,SBS受老化程度越高;采用二维相关红外分析技术,进一步发现SBS在超热老化过程中,氧原子同时会进攻SBS分子链上的亚甲基,并且主要进攻SBS中的非对称亚甲基,其次进攻对称亚甲基,形成自由基;通过同步相关谱图与异步相关谱图的对比分析,发现SBS在超热老化过程中,其氧化产物羰基的变化落后于醚键的变化,而羟基的变化又落后于羰基的变化,其氧化产物的生成速率为醚键>羰基>羟基;其中羰基的存在形式主要以醛酮为主,并伴随生成少量的羧酸。