冷颜料在红外隐身涂料中的应用

目的通过冷颜料降低目标的表面温度,起到红外隐身的作用。方法采用XRD衍射仪和紫外/可见光/近红外分光光度计等,分析颜料的相结构及近红外光谱特性。采用红外辐射率测量仪、紫外/可见光/近红外分光光度计和红外灯模拟太阳光照射,分析涂层的红外发射率及反射隔热性能。结果与炭黑颜料相比,铁铬黑颜料的近红外平均反射率为57%,且反射光谱与叶绿素基本一致;当填料质量分数为10%时,铁铬黑涂层的近红外反射率最大,平均反射率为39.2%,红外发射率为0.91;20%(质量分数)炭黑涂层和10%(质量分数)铁铬黑涂层相比,铁铬黑涂层的反射隔热效果明显,其平衡温度较普通炭黑涂层低8.8℃。结论红外隐身材料应考虑颜料对涂层红外发射率的影响,在满足涂层颜色的条件下尽量控制颜料的添加量,实际应用中以颜料添加10%(质量分数)为宜,在满足涂层反射隔热要求的同时,保证了涂层的红外发射率。     

HgCdTe红外焦平面阵列像素内灵敏度函数仿真

对于<2的欠采样成像红外搜索和追踪系统,点目标能量集中在单像素内。由于焦平面阵列像素内灵敏度（IPS：Intra-Pixel Sensitivity）存在空间非均匀性,会降低目标的能量和质心测量精度。传统的光点扫描实验测试和数值仿真方法可有效表征和分析IPS,但系统和模型复杂度高、效率低,且实验测试无法分析IPS空间非均匀性与探测器参数的关系。针对上述问题,提出基于蒙特卡洛方法的HgCdTe红外焦平面阵列IPS仿真模型,分析了IPS空间非均匀性的影响因素。结果表明,减小像素中心距或增大吸收层厚度,IPS的空间非均匀性减小;随波长增大,IPS的空间非均匀性增大。该仿真和分析对高能量集中点目标测量精度的提升具有重要参考意义。     

论红外探测系统的噪声等效温差

介绍了基于噪声等效温差(Noise Equivalent Temperature Difference,NETD)定义的NETD公式推导过程,讨论了相关系统参数对NETD的影响。然后分析了环境温度变化对NETD的影响,并给出了相同辐射功率差所对应的等效温差的MATLAB计算方法。     

一种基于ARM的人体红外测温系统

提出了一种基于ARM处理器的人体红外测温系统.该系统由MLX90615高精度医用数字红外传感器、超声波传感器、环境温度传感器、主控CPU单元和其他外围电路组成.MLX90615采集人体额头的红外辐射温度值并将其输入CPU,经过温度补偿和距离补偿,额头温度值被转换成对应的人体温度值,并显示在液晶屏上.实验表明,与其他系统...     

Optical properties of infrared transmitting materials

The choice of appropriate infrared transmitting materials for high-power laser applications necessitates a knowledge of various optical parameters. Because experimental data is often scant or unreliable in frequency regions of interest it has become important to be able to predict optical parameters from either theoretical or phenomenological models. This requires identification of the major physical mechanisms, and translation of this information into a useful model. Considerable progress has been made recently, especially with regard to the frequency dependence of refraction, absorption α and photoelasticity. It has been found, for example, that frequency dispersion is important at 10.6μm for all three of the latter quantities in most alkali-halides. For most semiconductors, on the other hand, only the effects on α are significant. It is shown that the mix of existing experimental data with recent theory is now providing us, for the first time, with a fairly comprehensive view of the magnitude, frequency dependence, and temperature dependence of optical parameters of infrared transmitting materials.     

基于图像行相关空中目标实时检测算法

针对复杂背景中弱小目标的侦测问题,提出一种弱小目标去背景检测的新方法。通过对图像做灰度反转,根据图像相邻行之间的相关性做去除背景的预处理,并计算图像中灰度值最大的像素点,得到目标的位置坐标,并对实拍的空中弱小目标视频图像进行实验验证。实拍的视频图像证明：该方法可对弱小目标进行检测,且检测速度快、抗噪声干扰性能强。     

新型扁丝中红外辐射器

根据红外线的辐射机理,设计了用于加热和烘燥纺织品的扁丝红外辐射器.辐射器的表面温度为886℃,采用铁铬铝合金材料,外形尺寸为1 800 mm× 125 mm×80 mm,功率为7000W.与常见的圆丝红外辐射器相比,扁丝中红外辐射器的热效率更高,寿命更长,热响应时间更快.     

Determination of Chinese honey adulterated with high fructose corn syrup by near infrared spectroscopy

The use of fibre optic diffuse reflectance near infrared spectroscopy (NIR) in combination with chemometric techniques has been investigated to discriminate authenticity of honey. NIR spectra of unadulterated honey and adulterated honey samples with high fructose corn syrup were registered within 10,000–4000 cm⁻¹ spectral region. Discriminant partial least squares (DPLS) models were constructed to distinguish between unadulterated honey and adulterated honey samples and main bands responsible for the discrimination of samples are in the range of 6000–10,000 cm⁻¹. For these models, the correct classification rate for calibration samples were above 90%. Hundred percentage of unadulterated honey and 95% of adulterated honey samples from test set were correctly classified after appropriate preprocessing of first derivative, 13 smoothing points, followed by mean centering pre-treatment and eight model factors, respectively. Our results showed that NIR spectroscopy data with chemometrics techniques can be applied to rapid detecting honey adulteration with high fructose corn syrup.     

基于傅里叶变换红外光谱技术对木耳中镰刀菌的识别检测

该研究建立了一种基于傅里叶变换红外光谱的木耳中镰刀菌的定性定量检测方法：对经高压灭菌的木耳样品分别接种木耳中常见的五种镰刀菌（层出镰刀菌189975、串珠镰刀菌340687、尖孢镰刀菌120618、木贼镰刀菌124121、茄病镰刀菌121547）,并于28 ℃,相对湿度80%的条件下进行储存培养,同时采集不同储存阶段的木耳样品在1 800~900 cm-1的红外光谱信息。分别运用主成分分析（PCA）、线性判别分析（LDA）以及偏最小二乘回归分析（PLSR）建立木耳中镰刀菌的快速识别检测模型。结果表明：LDA模型对受不同镰刀菌侵染的木耳样品的平均判别正确率达到87.50%,对受单一镰刀菌侵染的木耳样品霉变状态的平均判别正确率达到82.50%;PLSR模型对木耳样品中菌落总数的预测实现了较好的定量结果（R2 p=0.842 8,RMSEP=0.292 log CFU/g,RPD=2.81）;通过实际样品验证分析表明傅里叶变换红外光谱方法可以实现木耳中镰刀菌的快速识别检测。     

荔枝核提取物抗氧化活性及红外光谱特性

以荔枝核为原料,以95%的乙醇为提取剂,在超声波的作用下得到荔枝核乙醇提取物。利用提取物对DPPH自由基和羟自由基的清除能力评价其抗氧化活性;同时测定了提取物的总还原能力和总的抗氧化性。最后通过红外光谱对提取物进行了定性分析。实验结果表明:荔枝核提取物具有很强的抗氧化活性,其抗氧化能力大于BHT,小于维生素C;荔枝核提取物清除DPPH·和·OH的IC50分别为0.032、0.160mg/mL。每克荔枝核提取物总抗氧化能力相当于210mgVc的总抗氧化能力;从红外光谱的结果可知,荔枝核提取物主要为黄酮类物质。