Weak links in the BEE chain? Procurement,skills and employment equity in the metals and engineering industries

The Department of Trade and Industry's 2003 strategy identifies ‘Black Economic Empowerment’ (BEE) as being broad-based, inclusive, and part of a sustainable long-term growth and development strategy. In this, it is consistent with the 2001 Black Economic Empowerment Commission report, the ANC 2002 conference resolution and ultimately the ANC's Reconstruction and Development Programme of 1994. We use firm-level information in the metals and engineering industries to examine the actual nature and extent of BEE across the dimensions of ownership, procurement, employment equity and training. Its aim is to examine the relationships between BEE concepts and provisions and the responses that firms took in practice. Direct pressure for BEE in metals and engineering firms arises from legislation and regulatory provisions governing employment equity, skills development and procurement. It also follows from procurement provisions applying to large companies that buy from metals and engineering firms, as well as to mining firms and State-Owned Enterprises such as Eskom and Transnet.     

Environmental assessment of gunshot residue particles in the public domain of the United Kingdom

Only limited data currently exists on the inadvertent transfer of gunshot residue (GSR), or GSR-like particles through contact with public places. In this study, an assessment occurrence of GSR in public environments in England, UK was undertaken. Utilizing a stubbing sampling technique over 260 samples were collected from areas accessible to the public, including buses, trains, taxis, and train stations. Stub analysis was performed by Scanning Electron Microscopy with Energy Dispersive X-ray Analysis (SEM-EDX). The results showed no characteristic GSR particles were detected on any of the 262 samples taken. From these samples, a total of four indicative/consistent particles were identified on one train seat (2× BaAl, 2× PbSb). Although geographical location and firearm association is likely to influence GSR occurrence, the data suggests that the potential for inadvertent GSR transfer through contact with public transport and associated communal areas is insignificant. Further research assessing environmental background levels of GSR in additional geographical locations is critical in an evaluation of the potential for GSR transfer from the environment.     

纳米材料显现潜手印技术研究进展

介绍了纳米材料显现手印的概念及特点,并与普通有机荧光试剂显现方法作了比较。主要就半导体纳米材料、金属纳米材料显现潜手印技术进展作了综述与展望。     

A Situational Model of Displacement and Diffusion Following the Introduction of Airport Metal Detectors

Much of the discourse surrounding counterterrorism centers on the inevitability of displacement, or the substitution of another form of terrorist attack in place of the one that has been thwarted. Yet a longstanding tradition of research in situational crime prevention finds that displacement is far from inevitable, and often depends crucially on the specific features of the incidents in question. In fact, crime prevention efforts are often followed by a “diffusion of benefits” (i.e., crime reductions) to incidents, groups, or locations that were not the intended target of the intervention. The current study examines various forms of displacement and diffusion in response to airport metal detectors among terrorist groups that had been involved in the perpetration of aviation attacks prior to their implementation. Using data from the Global Terrorism Database, the findings from interrupted time series models suggest a complex set of displacement and diffusion effects with respect to alternative attack modes, target types, and weapon usage.     

A Comparison of Fingerprint Sweat Corrosion of Different Alloys of Brass

Fingerprint sweat from 40 donors was deposited onto samples of five α and α + β phase brasses, comprising five alloys with different copper and zinc concentrations, two of which also had the addition of small concentrations of lead. Visual grading of the visibility of the corrosion revealed that brasses with the least amount of zinc produced the most visible and fully formed fingerprints from the most donors. Consideration of previously reported mechanisms for the corrosion of brass suggests red copper (I) oxide as a likely corrosion product for low zinc brasses, and a consideration of the color, composition, and solubility of fingerprint sweat corrosion products suggests that copper (I) oxide produces good contrast and visibility with the brass substrate. Scanning electron microscope images of the corrosion of all five alloys confirmed the enhanced contrast between corroded and uncorroded areas for low zinc alloys.     

Scanning Electron Microscope Analysis of Gunshot Defects to Bone: An Underutilized Source of Information on Ballistic Trauma

Recent years have seen increasing involvement by forensic anthropologists in the interpretation of skeletal trauma. With regard to ballistic injuries, there is now a large literature detailing gross features of such trauma; however, less attention has been given to microscopic characteristics. This article presents analysis of experimentally induced gunshot trauma in animal bone (Bos taurus scapulae) using full metal jacket (FMJ), soft point (SP), and captive bolt projectiles. The results were examined using scanning electron microscopy (SEM). Additional analysis was conducted on a purported parietal gunshot lesion in a human cranial specimen. A range of features was observed in these samples suggesting that fibrolamellar bone response to projectile impact is analogous to that observed in synthetic composite laminates. The results indicate that direction of bullet travel can be discerned microscopically even when it is ambiguous on gross examination. It was also possible to distinguish SP from FMJ lesions. SEM analysis is therefore recommended as a previously underexploited tool in the analysis of ballistic trauma.     

Effect of temperature on rectifying Schottky barriers formed from fingerprint sweat corrosion of brass

Corrosive electrochemical processes of brass, including those resulting from fingerprint sweat, continue to be studied because of the widespread industrial use of brass. Here, we examine how increased temperature affects the relative abundance of fingerprint sweat corrosion products and the rectifying Schottky barrier formed between p-type copper (I) oxide corrosion and brass. X-ray photoelectron spectroscopy confirms increasing dezincification with increasing temperature. This leads to n-type zinc oxide replacing copper (I) oxide as the dominant corrosion product, which then forms a rectifying Schottky barrier with the brass, instead of copper oxide, when the temperature reaches c. 600°C. Using X-ray diffraction, resulting diodes show polycrystalline oxides embedded in amorphous oxidation products that have a lower relative abundance than the diode forming oxide. Conventional current/voltage (I/V) characteristics of these diodes show good rectifying qualities. At temperatures between c. 100 and c. 600°C, when neither oxide dominates, the semiconductor/brass contact displays an absence of rectification.