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1.
新型红外线金属网式燃气灶具可使燃气趋于完全燃烧,提高热效率,达到保护环境的目的。文中重点介绍了灶具的结构,并分析其节能原理。  相似文献   
2.
目的:观察乙肝Ⅲ号合近红外信息辐照治疗乙型肝炎肝纤维化的疗效。方法:选择乙型肝炎肝纤维化住院病人234例,分为乙肝Ⅲ号治疗组(76例)、近红外信息辐照组(73例)和联合治疗组(85例)。在基础治疗(包括甘利欣,复方丹参液等)上采用单纯的中药外敷、肝病治疗仪近红外信息辐照以及两联合治疗等三种不同方法,观察各组患临床症状、体征、肝功能以及相关指标如PGA、肝纤三项(透明质酸(HA)、层黏蛋白(LN)、CⅣ型胶原(CⅣ))、肝血流的变化。结果:3组皆能改善临床症状,但以联合治疗组为;3组肝功能复常比较,差异有显性,但组间比较,差异无显性;在改善PGA、肝纤三项和肝血流量方面,联合治疗组优于乙肝Ⅲ号治疗组和近红外信息辐照组。结论:乙肝Ⅲ号合近红外信息辐照对乙型肝炎肝纤维化有一定的治疗作用,且较单一方法疗效明显。  相似文献   
3.
签字笔水、圆珠笔油红外发光特性的研究   总被引:2,自引:0,他引:2  
目的记录不同激发光、接收滤光镜下,各种油墨红外发光强弱的程度,为文字检验提供基础性的研究。方法用多波段光源中510~650nm单色光激发各种油墨样本,全波段物证检验CCD系统记录样本在530~950nm接收滤光镜下出现的红外发光图像。结果多数油墨在接收滤光镜到达800~850nm时,呈现出强烈的红外发光状态,并随接收波段的上升而开始衰减。结论可利用某些油墨的发光与否,发光强与弱的特性,检验案件中涂改和涂抹字迹。  相似文献   
4.
目的建立安钠咖样品中咖啡因和苯甲酸钠快速定性和定量分析的红外光谱方法。方法采用高纯度咖啡因和苯甲酸钠混合制样的方法制备定性和定量建模样品,通过分析混合样品的红外光谱图,确定安钠咖样品中咖啡因和苯甲酸钠的特征吸收峰。采用偏最小二乘法(partial least squares,PLS)建立红外光谱定量模型。结果通过分析17个咖啡因和苯甲酸钠混合样品(咖啡因纯度范围10%~80%)的红外光谱图,确定了咖啡因的特征吸收峰为1698、1650、1237、972、743、609cm-1;苯甲酸钠的特征吸收峰为1596、1548、1406、845、708、679cm-1。将所有特征吸收峰均检出作为阳性判断依据时,48个安钠咖缴获样品中咖啡因和苯甲酸钠的阳性检出率均为100%。咖啡因PLS定量模型的线性范围为10%~80%,决定系数(R2)为99.9%,交叉验证均方差(root mean square error of cross validation,RMSECV)为0.68%,预测均方差(root mean square error of prediction,RMSEP)为0.91%;苯甲酸钠PLS定量模型的线性范围为20%~90%,R2为99.9%,RMSECV为0.91%,RMSEP为1.11%。配对样本t检验结果显示,高效液相色谱法和红外光谱法的测定结果差异无统计学意义。采用所建立的红外定量方法分析48个安钠咖缴获样品,咖啡因的纯度为27.6%~63.1%,苯甲酸钠的纯度为36.9%~72.3%。结论采用红外光谱法对安钠咖样品中的咖啡因和苯甲酸钠进行快速定性和定量分析,可提高检验鉴定效率、降低检验成本。  相似文献   
5.
Soil samples have potential to be useful in forensic investigations, but their utility may be limited due to the inherent variability of soil properties, the wide array of analytical methods, and complexity of data analysis. This study examined the differentiation of similar soils based on both gross (texture, color, mineralogy) and explicit soil properties (elemental composition, cation exchange, Fe‐oxyhydroxides). Soils were collected from Fallbrook and adjacent map units from Riverside and San Diego Counties in California. Samples were characterized using multiple techniques, including chemical extracts, X‐ray diffraction (XRD), and Fourier transform infrared spectroscopy. Results were analyzed using multiple analytical approaches to compare counties and land uses. Some analyses (XRD, extractions) were better at distinguishing among samples than others (color, texture). Ratios of rare earth elements were particularly useful for distinguishing samples between counties. This potential to “fingerprint” soils illustrates the usefulness of a comprehensive soil database for criminal investigators.  相似文献   
6.
运用套叠式手枪基础训练检查器(专利号CN200420054786.7)在南京森林公安高等专科学校2006级警察战术与指挥专业(特警班)射击课中运用,随机抽取50名学生为样本,分为对照组与实验组。结果表明,手枪基础训练检查器在射击课教学中操作简单、方便教学,实验班射击技能成绩优于对照班的学生。  相似文献   
7.
Forensic analysis of bicomponent fibers using infrared chemical imaging   总被引:2,自引:0,他引:2  
The application of infrared chemical imaging to the analysis of bicomponent fibers was evaluated. Eleven nominally bicomponent fibers were examined either side-on or in cross-section. In six of the 11 samples, infrared chemical imaging was able to spatially resolve two spectroscopically distinct regions when the fibers were examined side-on. As well as yielding characteristic infrared spectra of each component, the technique also provided images that clearly illustrated the side-by-side configuration of these components in the fiber. In one case it was possible to prepare and image a cross-section of the fiber, but in general the preparation of fiber cross-sections proved very difficult. In five of the 11 samples, the infrared spectra could be used to identify the overall chemical composition of the fibers, according to a published classification scheme, but the fiber components could not be spatially resolved. Difficulties that are inherent to conventional "single-point" infrared spectroscopy, such as interference fringing and sloping baselines, particularly when analyzing acrylic type fibers, were also encountered in the infrared chemical image analysis of bicomponent fibers. A number of infrared sampling techniques were investigated to overcome these problems, and recommendations for the best sampling technique are given. Chemical imaging results were compared with those obtained using conventional fiber microscopy techniques.  相似文献   
8.
The discrimination of noncolored transparent polyethylene bags was studied by several nondestructive and semidestructive analytical methods. X-ray diffraction, infrared spectroscopy, and optical microscopy (differential interference contrast microscopy and phase contrast microscopy) were applied to polyethylene films. X-ray diffraction was used to distinguish variations in the crystalline phase, infrared spectroscopy was used to distinguish variations in the molecular components, and optical microscopy was used to distinguish the different surface morphologies. The results show that X-ray diffraction classifies the crystalline phase of the film depending on whether it is made from low-density polyethylene, linear low-density polyethylene, or high-density polyethylene; that infrared spectroscopy is useful to distinguish the molecular components and it is the most discriminating technique; and that optical microscopy discriminate films easily by their morphological differences.  相似文献   
9.
This study takes the first step toward in situ analysis of powder drugs which does not require any alteration of the samples. A fast, inexpensive analytical method based on reflectance near-infrared (NIR) spectrometry and multivariate calibration was applied. A diode-array fiber-optic portable spectrometer in the 900-1700 nm range was employed. Samples were laboratory-prepared ternary powders (diacetylmorphine, caffeine, and paracetamol). Partial least squares regression was applied. The choice of the standard samples for calibration and validation was performed through a D-optimal experimental design. The explained variance was higher than 90%, and the relative root mean square errors were <2%. The number of principal components (6) was very low when compared with the number of raw variables (356 absorbance values). Response plots showed slopes and intercepts were very close to optimal values. Correlation coefficients ranged between 0.909 and 0.989. The method here proposed proved to be competitive with Fourier transform NIR spectrometry.  相似文献   
10.
Estimation of the time since death (postmortem interval [PMI]) is one of the most difficult problems in forensic investigations, and many methods currently are utilized to estimate the PMI. The goal of this study was to investigate the changes of attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra of rat brain from postmortem time 0-144 h. The intensity ratios of major absorbance bands were examined (I(1066)/I(1392), I(1168)/I(1392), I(1234)/I(1454), I(1301)/I(1392), I(1647)/I(2956), I(2921)/I(2850), and I(1647)/I(1539)). The spectra of rat brain displayed prominent changes with increasing PMI. The band at 2871 and 1737 per cm became weak with the time increasing and even disappeared at postmortem 96 and 72 h, respectively. A close linear correlation was shown between the relative absorption intensity and the PMI, and the I(1234) /I(1454) offered a stronger correlation (r = 0.973). Our results indicate that ATR-FTIR spectroscopy may be a useful technique for estimating the PMI.  相似文献   
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