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应用SEM/EDX和ICP-AES检测元素成份判定致伤工具 总被引:1,自引:1,他引:0
目的应用扫描电镜/能谱联合分析仪(Scanning electron microscopy & Energy dispersive X-ray apparatus SEM/EDX)和电感耦合原子发射等离子光谱(inductively coupled plasma-atom emission spectrometer ICP-AES)对金属致伤工具本身及所致创口残留物元素成分分析,探讨两者在推断认定此类工具的应用条件及价值.方法镀层和普通铁质工具在乳猪皮肤各致创5例,SEM/EDX对创口内遗留金属颗粒元素检测;用标准样品检测实验方法的精确度;普通铁质工具于刀背、刀刃处各取5个样本,ICP-AES测定元素成分与含量.结果镀锌工具所致创口中存在单一含有锌的金属颗粒,镀黄铜工具则同时含有锌和铜,未发现其它元素;不锈钢或普通铁质菜刀创口中,发现同时含有铁、铬、硅或铁、锰、硅的颗粒;除5号菜刀外同一把铁质菜刀在刀刃、刀背处元素含量无明显差别;ICP-AES分析表明不锈钢菜刀之间在铬、锰、硅、铜、钼和5号刀背部以及其他铁质菜刀在锰、硅元素含量差别具有显著意义,5号刀刃部锰、硅、钼、钛、磷、硫、镍元素RSD明显升高.结论SEM/EDX可以通过创口的检测对金属致伤工具进行种类的推断认定,ICP-AES则可在同种类致伤工具中进行相对同一的判定有应用价值. 相似文献
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人体毛发尖部形态的扫描电镜研究 总被引:4,自引:0,他引:4
采用扫描电镜观察人体毛发尖部微观形态特征,总结归纳了人体主要几个部位毛发尖部形态的八种类型,探讨各类毛尖形状其形成的可能条件、分布的规律性以及修剪后端部的变化情况,为研究人体毛发生长机理、法庭科学的毛发鉴定工作提供依据。 相似文献
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Rebecca Weston 《Journal of family violence》2008,23(6):483-493
Men’s emotional abuse and violence have a broad and pervasive impact on women that may include long-term effects on women’s
attachment and relationship quality. In this longitudinal study, women’s Wave 6 ratings of their insecure attachment were
hypothesized to mediate the relationship between partners’ Wave 5 abuse (emotional and physical) and Wave 6 relationship quality,
with differences in associations by women’s Wave 5 self-classification as secure or insecure. Mediation was tested with data
from a sample of 574 African American, Euro-American, and Mexican American community women who had completed at least three
waves of a six wave study. Differences occurred in the final structural equation models by women’s Wave 5 attachment style,
with direct paths from emotional abuse to insecure attachment and from violence to relationship quality for both groups, but
direct effects of violence on relationship quality only for insecurely attached women. 相似文献
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Ferllini R 《Journal of forensic sciences》2012,57(3):683-690
Stab wounds upon bone are analyzed to interpret the weapon used and the physical context in which the attack occurred. The literature demonstrates that most research conducted pertaining to wound patterns has been carried out on defleshed and unclothed bone samples, not adequately replicating actual circumstances. For this research, six half pig torsos (Sus scrofa), fleshed (including muscle, fat, epidermis, and dermis layers) and clothed, were stabbed using three knife types, applying both straight and downward thrusts. Analysis conducted macroscopically and through a scanning electron microscope with an environmental secondary electron detector revealed a general lack of consistency in wound pattern and associated secondary effects. Consequently, it was not possible to establish wound pattern per knife type as suggested in previous research or relate it to stab motion. Advantage of microscopic analysis was evident in recognizing wound traits and observation of trace evidence not visible macroscopically. 相似文献
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Several nondestructive and semidestructive analyses were used to discriminate colorless transparent polyethylene bags. Transparent plastic bags made from low-density and linear low-density polyethylene usually contain antiblocking agents to prevent sticking of the film, which makes it difficult to open the mouths of plastic bags. Inorganic antiblocking agents are uniformly dispersed in polyethylene films, so they are easily observed using optical microscopy. The particle size distributions of the antiblocking agents were compared by statistical tests. Particle composition was examined by elemental analysis using energy-dispersive X-ray spectrometry with a scanning electron microscope and by molecular vibration analysis using a sensitive microscopic Raman spectrometer. The compositions could be determined nondestructively on the basis of the results. These data reinforce the morphological discrimination. Morphological discrimination of the dispersed antiblocking agent powders, statistical comparison of particle size distributions, and compositional analysis of the antiblocking agents strengthen the ability to discriminate polyethylene films. 相似文献
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ABSTRACT Brand hate is defined as a severe dislike for a product or service by the consumer. Although brand hate has been recognized as a critical element, in the political market, there is a lack of understanding of the impact of brand hate on voters. This study is an attempt to examine the antecedents and consequences of brand hate in the political market. The study reveals that unmet expectations, symbolic incongruity, and ideological incompatibility of electorates have a significant positive impact on brand hate intensity. The result shows that political product involvement significantly mediates the relationship between unmet expectations, symbolic incongruity, and ideological incompatibility and brand hate intensity. The study further reveals that as an outcome of political brand hate, electorates put emphasis on either brand avoidance and/or brand extremism. The outcome of this study may help political parties gain knowledge about the impact of political brand hate. 相似文献
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Scanning Electron Microscopy–Energy‐Dispersive X‐Ray (SEM/EDX): A Rapid Diagnostic Tool to Aid the Identification of Burnt Bone and Contested Cremains
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Sarah T. D. Ellingham Ph.D. Tim J. U. Thompson Ph.D. Meez Islam Ph.D. 《Journal of forensic sciences》2018,63(2):504-510
This study investigates the use of Scanning electron microscopy–energy‐dispersive X‐ray (SEM‐EDX) as a diagnostic tool for the determination of the osseous origin of samples subjected to different temperatures. Sheep (Ovis aries) ribs of two experimental groups (fleshed and defleshed) were burned at temperatures of between 100°C and 1100°C in 100°C increments and subsequently analyzed with the SEM‐EDX to determine the atomic percentage of present elements. Three‐factor ANOVA analysis showed that neither the exposure temperature, nor whether the burning occurred with or without soft tissue present had any significant influence on the bone's overall elemental makeup (p > 0.05). The Ca/P ratio remained in the osseous typical range of between 1.6 and 2.58 in all analyzed samples. This demonstrates that even faced with high temperatures, the overall gross elemental content and atomic percentage of elements in bone remain stable, creating a unique “fingerprint” for osseous material, even after exposure to extreme conditions. 相似文献
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Micha Mandel Ph.D. Osnat Israelsohn Azulay Ph.D. Yigal Zidon Ph.D. Tsadok Tsach M.Sc. Yaron Cohen M.Sc. 《Journal of forensic sciences》2018,63(4):1269-1274
Classification of particles as gunshot residues (GSRs) is conducted using a semiautomatic approach in which the system first classifies particles based on an automatic elemental analysis, and then, examiners manually analyze particles having compositions which are characteristic of or consistent with GSRs. Analyzing all the particles in the second stage is time consuming with many particles classified by the initial automated system as being potentially GSRs excluded as such by the forensic examiner. In this paper, a new algorithm is developed to improve the initial classification step. The algorithm is based on a binary tree that was trained on almost 16,000 particles from 43 stubs used to sample hands of suspects. The classification algorithm was tested on 5,900 particles from 23 independent stubs and performed very well in terms of false positive and false negative rates. A routine use of the new algorithm can reduce significantly the analysis time of GSRs. 相似文献
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Since the introduction in 2001 of a urine-based detection method for recombinant erythropoietin (rHuEPO), transfusion-doping practices have regained interest. To address this problem, an efficient antidoping test designed to obtain direct proof of allogeneic blood transfusion was developed and validated. This test, based on flow cytometry analysis of red blood cell (RBCs) phenotypes, was used to determine the absence or the presence of numerous RBCs populations in a blood sample. A such, it may constitute a direct proof of an abnormal blood population resulting from homologous transfusion. Single-blind and single-site studies were carried out to validate this method as a forensic quality standard analysis and to allow objective interpretation of real cases. The analysis of 140 blood samples containing different percentages (0-5%) of a minor RBCs population were carried on by four independent analysts. Robustness, sensitivity, specificity, precision and stability were assessed. ISO-accredited controls samples were used to demonstrate that the method was robust, stable and precise. No false positive results were observed, resulting in a 100% specificity of the method. Most samples containing a 1.5% minor RBCs population were unambiguously detected, yielding a 78.1% sensitivity. These samples mimicked blood collected from an athlete 3 months after a homologous blood transfusion event where 10% of the total RBCs present in the recipient originated in the donor. The observed false negative results could be explained by differences in antigen expression between the donor and the recipient. False negatives were more numerous with smaller minor RBCs populations. The method described here fulfils the ISO-17025 accreditation and validation requirements. The controls and the methodology are solid enough to determine with certainty whether a sample contains one or more RBCs populations. This variable is currently the best indicator for homologous blood transfusion doping. 相似文献