The leaching of α-spodumene

An investigation into the direct leaching of α-spodumene has being warranted due to increasing societal interest in lithium-ion battery technology. The direct leaching of α-spodumene utilising a caustic autoclave process was investigated, in aspirations of leaching significant quantities of lithium from the silicate matrix of α-spodumene. The influence of reagent dosage, temperature, reaction time and particle size on the extraction efficiency of lithium were investigated. From the investigations conducted it became evident that the leaching efficiency of α-spodumene was consistently greater than 40.00% under the optimal conditions. The optimal conditions evaluated throughout the investigation were found to occur at 573.15 kelvin, 14 molar NaOH, a 6 hour residence time and a P80 of 325 μm. The lithium recovered to solution is present as a hydroxide species, of which is in significant demand within the lithium-ion battery production industry. Sodium silicate or ‘water glass’ was also found to be present within the leach products adding a potential valuable by-product to the process investigated

Comparison of carcass composition, performance, and tissue deposition rates among breeds of swine

A study was conducted to evaluate differences in performance, carcass traits, and tissue deposition rates among breeds of swine entered in the 2003 National Barrow Show Progeny Test. The test consisted of 362 barrow and gilt progeny from sires within each of the 8 breeds evaluated. Breeds tested were Berkshire (n = 158), Duroc (n = 76), Chester White (n = 53), Yorkshire (n= 31), Spotted (n = 15), Landrace (n = 15), Poland (n = 8), and Hampshire (n = 6). Due to small sample size, the Spotted, Landrace, Poland, and Hampshire breeds were combined in an All Other Breeds (AOB) category. Progeny were weighed and scanned beginning at a group mean body weight of approximately 64 kg., while off-test measurements were taken at approximately 109 kg. Deposition rates were estimated for 10th rib loin muscle area, 10th rib off-midline backfat, and intramuscular fat percentage of the longissimus dorsi

Criminal Careers in Cyberspace: Examining Website Failure within Child Exploitation Networks

Publically accessible, illegal, websites represent an additional challenge for control agencies, but also an opportunity for researchers to monitor, in real time, changes in criminal careers. Using a repeated measures design, we examine evolution in the networks that form around child exploitation (CE) websites, over a period of 60 weeks, and determine which criminal career dimensions predict website failure. Network data were collected using a custom-designed web-crawler. Baseline survival rates were compared to networks surrounding (legal) sexuality and sports websites. Websites containing CE material were no more likely to fail than comparisons. Cox regression analyses suggest that increased volumes of CE code words and images are associated with premature failure. Websites that are more popular have higher odds of survival. We show that traditional criminal career dimensions can be transferred to the context of online CE and constitute some of the key determinants of an interrupted career

A review of fused-ring carbazole derivatives as emitter and/or host materials in organic light emitting diode (OLED) applications

This review focuses on fused-ring carbazole derivatives, their molecular design, electronic and photophysical properties, and in particular their applications as the emitter and/or the host material in the emitting layer of organic light emitting diodes (OLEDs), with emphasis on recent developments. This review is timely because of the rapidly expanding research into fused-ring carbazoles, predominantly indolocarbazole, indenocarbazole, benzofurocarbazole, benzothienocarbazole and diindolocarbazole derivatives. To our knowledge this class of materials has not been reviewed previously. The appeal of fused-ring carbazoles is their extended π-electron systems with good thermal stability, tunable frontier orbital energies that enable a wide gamut (red, green, blue and white) emission colour, high photoluminescence quantum yields, and versatility for chemical functionalisation at different sites, leading to outstanding OLED efficiencies. This review is divided into sections according to the molecules’ role in OLEDs: namely, as conventional luminescent emitters – especially in the deep-blue region; as state-of-the-art hosts for phosphorescent iridium-based emitters; as thermally activated delayed fluorescence (TADF) emitters with high external quantum efficiency; and as multiresonance (MR) emitters with unprecedented high colour purity. We conclude by highlighting the challenges and the great opportunities for fused-ring carbazole derivatives in OLEDs and other optoelectronic applications

The Structure and Content of Online Child Exploitation Networks

The emergence of the Internet has provided people with the ability to find and communicate with others of common interests. Unfortunately, those involved in the practices of child exploitation have also received the same benefits. Although law enforcement continues its efforts to shut down websites dedicated to child exploitation, the problem remains uncurbed. Despite this, law enforcement has yet to examine these websites as a network and determine their structure, stability and susceptibleness to attack. We extract the structure and features of four online child exploitation networks using a custom-written webpage crawler. Social network analysis is then applied with the purpose of finding key players – websites whose removal would result in the greatest fragmentation of the network and largest loss of hardcore material. Our results indicate that websites do not link based on the hardcore content of the target website; however, blogs do contain more hardcore content per page than non-blog websites

Helminth Parasites of Rails and Host-Parasite Relationships of the Trematode Protechinostoma mucronisertulatum

In a survey of 15 soras (Porzana carolina) and 31 Virginia rails (Rallus limicola) collected in Iowa during May-September 1963, Protechinostoma mucronisertulatum was the most frequently encountered trematode of the sora. It does not occur in the Virginia rail. Experimentally-developed metacercariae and adults were obtained and host-parasite relationships studied with special reference to annual incidence of infection in snails. Additional helminths of the sora and the Virginia rail include several representing new host records

Comparing Methods for Detecting Child Exploitation Content Online

The sexual exploitation of children online is seen as a global issue and has been addressed by both governments and private organizations. Efforts thus far have focused primarily on the use of image hash value databases to find content. However, recently researchers have begun to use keywords as a way to detect child exploitation content. Within the current study we explore both of these methodologies. Using a custom designed web-crawler, we create three networks using the hash value method, keywords method, and a hybrid method combining the first two. Results first show that the three million images found in our hash value database were not common enough on public websites for the hash value method to produce meaningful result. Second, the small sample of websites that were found to contain those images had little to no videos posted, suggesting a need for different criteria for finding each type of material. Third, websites with code words commonly known to be used by child pornographers to identify or discuss exploitative content, were found to be much larger than others, with extensive visual and textual content. Finally, boy-centered keywords were more commonly found on child exploitation websites than girl-centered keywords, though not at a statistically significant level. Applications for law enforcement and areas for future research are discussed

Finding the Key Players in Online Child Exploitation Networks

The growth of the Internet has been paralleled with a similar growth in online child exploitation. Since completely shutting down child exploitation websites is difficult (or arguably impossible), the goal must be to find the most efficient way of identifying the key targets and then to apprehend them. Traditionally, online investigations have been manual and centered on images. However, we argue that target prioritization needs to take more than just images into consideration, and that the investigating process needs to become more systematic. Drawing from a web crawler we specifically designed for extracting child exploitation website networks, this study 1) examines the structure of ten child exploitation networks and compares it to a control group of sports-related websites, and 2) provides a measure (network capital) that allows for identifying the most important targets for law enforcement purposes among our sample of websites. Results show that network capital — a combination between severity of content (images, videos, and text) and connectivity (links to other websites) — is a more reliable measure of target prioritization than more traditional measures of network centrality taken alone. Policy implications are discussed