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1.
利用暗记特征对HP系列彩色激光打印文件鉴别的研究   总被引:1,自引:1,他引:0  
对激光打印文件的鉴别,尤其是彩色激光打印文件的鉴别,历来是可疑文件检验领域的难点和重点。利用暗记特征则为此类文件的鉴别提供了一种有效方法,即采用光学检验方法,对激光彩色打印文件暗记进行显现,利用暗记点阵形态特征和点阵排列含义特征等,为彩色激光打印机具的种类鉴别和个体鉴别提供了有效的鉴别依据。  相似文献   
2.
Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO.  相似文献   
3.
浅谈运用面部微表情技术避免“奥塞罗错误”   总被引:1,自引:0,他引:1  
公安审讯中经常会遇到无辜者看似有罪或者有罪者伪装无辜的情况,使审讯人员真假难辨。根据人的最初情绪反应的真实性,以被审讯人的情绪反应作为突破口,利用面对指控时无辜者的愤怒情绪和有罪者的恐惧情绪区别出两者,即运用面部微表情的知识辨别愤怒与恐惧,从而区别出无辜者和有罪者,并且通过表情的特性,左右脸表情的一致性和肢体语言、面部表情和话语的一致性三个方面鉴别出真正的无辜者和伪装无辜的有罪者。  相似文献   
4.
采用解剖学方法对8尾东方蝾螈的外形和内脏进行了系统研究。结果表明,东方蝾螈的口裂很宽,口咽腔底壁的前方有不发达的舌。食管短,黏膜上有纵行皱襞;胃呈纺锤形的长囊,肌层发达,贲门口较大;直肠粗大;肝较为发达,有胆囊;胰独立,不与肝混合,但胰管与胆管合并。肺为2个锥形的薄壁长囊,构造简单,囊壁形成蜂窝状。输尿管不直接通膀胱,尿液先到泄殖腔,然后再到膀胱。雄性大鲵无专门的输精管,而是借助于输尿管输精。雌性大鲵有卵巢1对,呈带形的囊状卵巢。  相似文献   
5.
应用光镜和电镜对猪和兔附红细胞体的显微和超微结构进行了观察。结果表明,猪和兔附红细胞体在光镜和电镜下的形态结构、大小以及在红细胞上的附着方式等均无显著差别,其形态多为球形、卵圆形,直径0.2~2.5μm,在红细胞表面以一根或数根纤丝连接成串珠状或单个寄生。在透射电镜下,首次观察到附红细胞体边缘有一段20~30nm厚的光亮区域,并且在扫描和透射电镜下同时观察到附红细胞体的出芽生殖现象。由此推测,附红细胞体的发育方式为成熟的附红细胞体以出芽的方式产生1个未成熟形态的附红细胞体,随着未成熟形态附红细胞体的发育,逐渐从成熟附红细胞体体内脱离出来,最后以纤丝与成熟附红细胞体相连接;脱离出来的未成熟形态的附红细胞体黏附到同一红细胞或临近红细胞的膜上,最终发育成1个成熟的附红细胞体。  相似文献   
6.
Abstract: Recently a small sampled cadaver study (n = 4) suggested that the human eyeballs are placed closer to the orbital roof and lateral orbital wall as first reported in the anatomical literature many years previously. This contrasts with central positioning of the eyeball within the orbit as advocated by the facial approximation literature. Given the limits of such small samples, this study re-examined globe position in nine new cadavers to help clarify which relationship is accurate. The results essentially confirm prior empirical findings except that the mean lateral divergences from the orbit center were found to be larger—the eyeball was found to be “displaced” 1.4 mm superiorly and 2.4 mm laterally. Medians calculated across all 13 cadavers from this study and the above-mentioned recent report refine these measurements to 1.4 and 2.3 mm respectively. Globe projection values were identical to those observed for living individuals (c. 16 mm).  相似文献   
7.
Both the columnar‐thin‐film (CTF) and the vacuum‐metal‐deposition (VMD) techniques for visualizing sebaceous fingermarks require the deposition of a material thereon in a vacuum chamber. Despite that similarity, there are many differences between the two techniques. The film deposited with the CTF technique has a columnar morphology, but the film deposited with the VMD technique comprises discrete islands. A split‐print methodology on a variety of fingermarked substrates was used to determine that the CTF technique is superior for developing fingermarks on clear sandwich bags and partial bloody fingermarks on stainless steel. Both techniques are similar in their ability to develop fingermarks on glass but the CTF technique yields higher contrast. The VMD technique is superior for developing fingermarks on white grocery bags and the smooth side of Gloss Finish Scotch Multitask? tape. Neither technique worked well for fingermarks on black garbage bags.  相似文献   
8.
This study measured and assessed facial soft tissue depths (FSTDs) in adult female Chinese and New Zealand (NZ) Europeans (Caucasoids). Ultrasound was used to obtain depths at nine landmarks on 108 healthy subjects (51 Chinese, 57 NZ European), erect positioned, of same age group (18–29 years). Height and weight were also recorded. Statistical analysis focused on comparison of tissue depth between the two ancestry groups and the influence of Body Mass Index (BMI) (kg/m2). Results showed mean depth differences at Supra M2 and Infra M2 landmarks significantly greater for Chinese than Caucasoid women for all three BMI Classes (BMI <20, 20 ≤ BMI < 25, 25 ≤ BMI < 30), even BMI <20. For both groups BMI positively correlated with FSTD values at all landmarks except Labrale superius. This study enabled ancestry and BMI influence on FSTDs to be observed and compared for two distinct groups. Results add to knowledge about facial tissue depth variation.  相似文献   
9.
林楠 《学理论》2011,(20):213-214
为了考察幼儿情绪识别能力培养的效果,我们对50名儿童进行情绪识别培养,结果发现:幼儿情绪识别能力培养效果明显;不同年龄段培养的效果差异显著,3岁效果最明显,3岁也是正性情绪培养的关键期;正性情绪识别能力培养存在性比差异,女生比男生快;幼儿负性情绪识别能力培养3、4岁都有质的改变。结果提示:幼儿情绪识别能力发展迅速,培养效果明显。不同类型情绪培养效果有分离,正性、负性培养作用明显。  相似文献   
10.
袁中标 《政法学刊》2003,20(6):65-66
相貌侦查是指刑事侦查部门从事模拟画像及颅骨复原等专业技术的人员专门绘制嫌疑人或塑造死者肖像用于通缉疑犯、查找死者身份的专门侦查工作。这种技术员再创造的能力需要侦查人员的丰富想象力。  相似文献   
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