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141.
本文紧紧围绕“变革”和“权力”这两个核心概念所揭示的要点,运用宏观、中观、微观相结合的方法,对近代中日变法维新的成败原因做出动态分析。全文以变革为主线,以权力为焦点,通过比较内部条件之不同、个人和组织的权力资源掌握程度之不同以及权力获取和运行效用之不同,将有关因素归结为动力与内部相关条件、主体与组织化程度以及集权与强制力三个分析层次。各层次间既相互独立,各自构成一个分析视角,同时,三者之间又具有密切的逻辑关系,形成全方位的分析框架。  相似文献   
142.
Manual localization of bone fragments on the ground or on complex surfaces in relation to accidents or criminal activity may be time‐consuming and challenging. It is here investigated whether combining a near‐infrared hyperspectral camera and chemometric modeling with false color back‐projection can be used for rapid localization of bone fragments. The approach is noninvasive and highlights the spatial distribution of various compounds/properties to facilitate manual inspection of surfaces. Discriminant partial least squares regression is used to classify between bone and nonbone spectra from the hyperspectral camera. A predictive model (>95% prediction ability) is constructed from raw chicken bones mixed with stone, sand, leaves, moss, and wood. The model uses features in the near‐infrared spectrum which may be selective for bones in general and is able to identify a wide variety of bones from different animals and contexts, including aged and weathered bone.  相似文献   
143.
Micro‐Raman spectroscopy was applied to forensic identification of pigments in paint chips and provided differentiation between paint samples. Sixty‐six blue automotive paint samples, 26 solid and 40 metallic were examined. It was found that the majority of the collected Raman spectra provided information about the pigments present. However, in some cases, fluorescence precluded pigment identification. Using laser excitation at longer wavelengths or pretreatment to effect photobleaching often resulted in reduced fluorescence, particularly for solid color samples, and allowed pigment identification. The examined samples were compared pairwise taking into account number, location, and intensity of absorption bands in their infrared spectra. The estimated discrimination power ranged from 97% for solid paint samples to 99% for metallic paint samples.  相似文献   
144.
Seals are traditionally used in the Far East Asia to stamp an impression on a document in place of a signature. In this study, an accuser claimed that a personal contract regarding mining development rights acquired by a defendant was devolved to the accuser because the defendant stamped the devolvement contract in the presence of the accuser and a witness. The accuser further stated that the seal ink stamped on the devolvement contract was the same as that stamped on the development rights application document. To verify this, the seals used in two documents were analyzed using micro‐attenuated total reflectance Fourier transform infrared spectroscopy and infrared spectra. The findings revealed that the seals originated from different manufacturers. Thus, the accuser's claim on the existence of a devolvement contract was proved to be false.  相似文献   
145.
拉曼光谱技术在物证鉴定中的应用   总被引:1,自引:0,他引:1  
拉曼光谱技术具有不接触样品、不破坏样品、无需样品制备等优点,适用于法庭科学领域不同种类物证的分析.本文综述了拉曼光谱技术在物证鉴定中的应用,并对该技术的发展趋势进行了展望.  相似文献   
146.
荧光检验法在朱墨时序鉴定中的应用研究   总被引:1,自引:0,他引:1  
朱墨时序鉴定一直是文书司法鉴定实践中常见的鉴定项目,也是研究的热点和疑难问题.通过实验研究并结合检案实践,较系统地阐述了视频荧光光谱检验法和显微荧光检验法在朱墨时序鉴定的具体应用,探讨了荧光检验的技术要点.研究表明,荧光检验法(特别是显微荧光检验法)具有普通显微检验法的优点,同时对普通显微检验法中难以观察到的印文或文字色料荧光特性及色料的微观分布状态,具有明显的检验效果,是普通显微检验法有效的补充检验手段.  相似文献   
147.
目的针对犯罪现场血液遗留时间的判断问题,实验以不同遗留时间的血液为研究对象,建立基于拉曼光谱的血液遗留时间的辨别方法。方法采集遗留时间为0.5h~240h的指尖血液样本,获取其拉曼光谱数据,经校正和平滑处理后,对数据进行归一化。利用RSD值评价光谱的稳定性,选取前10个主成分和6个重要波段分别建立模型,利用预测集测试模型效果。结果相同遗留时间血液的拉曼光谱具有较好的稳定(RSD<0.2),不同遗留时间血液的拉曼光谱在680cm-1等6个波段有明显的强度变化。前10个主成分建立的PLSR模型,其r2=0.9927。6个重要波段建立的PLSR模型,预测集效果r2=0.8797。结论利用拉曼光谱结合建模分析是一种无损快速的评估血液遗留时间的方法。  相似文献   
148.
The backings of 90 black electrical tapes were analyzed to evaluate the chemical components of these films, the ability of individual techniques to discriminate samples, and the ability of the techniques combined to distinguish samples. The techniques utilized and their respective discrimination results were stereomicroscopy and physical measurements, to include observation of surface features of the backing, width, and thickness measurements (c. 64%); Fourier transform infrared spectroscopy (FTIR) using a microscope accessory (c. 83%); pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS; c. 81%); and scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS; c. 87%). Ninety-four percent of the backings were discriminated through this combination of analytical methods. Finally, evaluating these results in conjunction with previously published data on the analysis of the adhesives from the same set of electrical tapes provided an overall discrimination of nearly 96%.  相似文献   
149.
Thin layer chromatography (TLC) is a scientific methodology that can be used to compare and characterize ink formulations. Occasionally, when evaluating chromatographic profiles on a TLC plate with ambient light, different ink formulations, or the same inks from different batches, may appear indistinguishable. The use of filtered light can be very effective to illuminate characteristics that are not readily apparent with ambient light. There are a diverse number of components commonly found in writing inks, and it may be that some of them respond to particular wavelengths of energy that are not visible to the unaided eye (i.e., colorless). There has been very little information published that addresses the use of filtered light for evaluating TLC plates. Twenty-nine ballpoint writing ink samples were selected for TLC analysis. Further evaluation using an alternate light source, coupled with the appropriate filter, proved to be an effective means for definitive discrimination in some cases.  相似文献   
150.
Determination of wound vitality and estimation of wound age are central issues in daily forensic practice. The objective of this study was to develop a new and rapid method for determining wound vitality and estimating wound age in bruises using electric impedance spectroscopy. Forty Sprague-Dawley rats (140-170 g) were divided into five groups: group 1 (n=8): controls, group 2 (n=8): postmortem bruises, group 3 (n=8): bruises 1 h before death, group 4 (n=8): bruises 3 h before death, group 5 (n=8): bruises 6 h before death. Measurements of the right gluteus maximus muscle were taken at 6, 24, and 48 h after the rats were sacrificed by cervical dislocation. The results from this study indicate that electric impedance spectroscopy is clearly sensitive enough to differentiate between vital and postmortem wound infliction and to determine the survival time after the infliction of an injury.  相似文献   
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