Liquid-Crystal Thermosets, a New Generation of High-Performance Liquid-Crystal Polymers

One of the major challenges for NASA's next-generation reusable-launch-vehicle (RLV) program is the design of a cryogenic lightweight composite fuel tank. Potential matrix resin systems need to exhibit a low coefficient of thermal expansion (CTE), good mechanical strength, and excellent barrier properties at cryogenic temperatures under load. In addition, the resin system needs to be processable by a variety of non-autoclavable techniques, such as vacuum-bag curing, resin-transfer molding (RTM), vacuum-assisted resin-transfer molding (VaRTM), resin-film infusion (RFI), pultrusion, and advanced tow placement (ATP). To meet these requirements, the Advanced Materials and Processing Branch (AMPB) at NASA Langley Research Center developed a new family of wholly aromatic liquid-crystal oligomers that can be processed and thermally cross-linked while maintaining their liquid-crystal order. All the monomers were polymerized in the presence of a cross-linkable unit by use of an environmentally benign melt-condensation technique. This method does not require hazardous solvents, and the only side product is acetic acid. The final product can be obtained as a powder or granulate and has an infinite shelf life. The obtained oligomers melt into a nematic phase and do not exhibit isotropization temperatures greater than the temperatures of decomposition (Ti > T(sub dec)). Three aromatic formulations were designed and tested and included esters, ester-amides, and ester-imides. One of the major advantages of this invention, named LaRC-LCR or Langley Research Center-Liquid Crystal Resin, is the ability to control a variety of resin characteristics, such as melting temperature, viscosity, and the cross-link density of the final part. Depending on the formulation, oligomers can be prepared with melt viscosities in the range of 10-10,000 poise (100 rad/s), which can easily be melt-processed using a variety of composite-processing techniques. This capability provides NASA with custom-made matrix resins that meet the required processing conditions for the fabrication of textile composites. Once the resin is in place, the temperature is raised to 375 C and the oligomers are cross-linked into a high-glass-transition-temperature (Tg) nematic network without releasing volatiles. The mechanical properties of the fully crosslinked, composite articles are comparable to typical composites based on commercially available epoxy resins

Enzymkinetiken steuern den initialen Streuabbau in Gründlandflächen unterschiedlicher Nutzungsintensität

Extrazelluläre hydrolytische Enzyme (EHEs), die überwiegend von Bodenmikroorganismen produziert werden, übernehmen eine wichtige Rolle beim Umsatz der organischen Substanz im Boden. Die Zusammenhänge zwischen Enzymkinetiken und Abbauraten organischer Substanz sind allerdings kaum untersucht. Als Kenngrößen des katalytischen Verhaltens von EHEs können die limitierende Umsatzrate (Vmax) sowie die apparente Substrataffinität (Km) mittels der Michaelis-Menten-Gleichung angenähert werden. Am Abbau von Cellulose z.B. sind Enzyme aus drei verschiedenen Klassen beteiligt. So katalysieren Cellotriosidasen (CTH), die Abspaltung von drei Glucose-Molekülen und Cellobiohydrolasen (CBH) die Umsetzung zu Cellobiose. beta-Glucosidasen (BG) nutzen Cellobiose und zerlegen dieses Substrat in einzelne Glucose-Moleküle. Somit liegt die Vermutung nahe, dass z.B. maximale Umsatzraten (Vmax) von BG durch die Km-Werte von CBH und CTH reguliert werden. Um den Einfluss unterschiedlicher Streuqualität auf solche Interaktionen zwischen verschiedenen Enzymen zu testen wurden Teebeutel mit grünem Tee (C/N Verhältnis 12) und Teebeutel mit Rooibos-Tee (C/N Verhältnis 43) in Anlehnung an Keuskamp et al. (2013) für drei Monate auf je 25 unterschiedlich intensiv bewirtschafteten Grünlandflächen der Biodiversitätsexploratorien (Hainich, Schorfheide) eingebracht. In den ausgebrachten, 3-monatig-exponierten, Teeproben wurden die katalytischen Eigenschaften der oben genannten EHEs sowie die Enzymaktivitäten von Phenol- und Peroxidasen gemessen. Die bisher ermittelten kinetischen Parameter der EHEs die am Abbau von Zellulose beteiligt sind weisen deutlich auf die unterschiedlichen Abbaumuster der beiden Teesorten hin. In den Rooibostee-Proben sind die vermuteten Beziehungen zwischen den Vmax-Werten von BG und den Km-Werten der anderen Cellulasen nachzuweisen und stehen in Beziehung zur Abbaurate. In den Grüntee-Proben dagegen bestehen Beziehungen zwischen den Vmax-Werten aller drei Cellulose abbauenden Enzyme

A fresh start for screening under the Habitats Regulations: Case c-323/17 People Over Wind, Peter Sweetman v Coillte Teoranta [2018] Ecr I-244

This is the author accepted manuscript. The final version is available from SAGE Publications via the DOI in this recordFor over twenty-five years, the courts have been delivering judgments that shape and refine the requirements of the Habitats Directive. The recent CJEU judgment of People Over Wind, Peter Sweetman v Coillte Teoranta [2018] ECR I-244 provides further clarification that will keep developers and decision-makers on their toes. In the judgment delivered in April 2018, the sole question for the court was whether, or in what circumstances, mitigation measures can be considered when carrying out screening for appropriate assessment under Article 6(3) of the Habitats Directive? The court’s response to this question is significant. In a confident judgment, it was held that mitigation measures cannot be considered when carrying out screening for appropriate assessment. This case note provides a detailed overview of the judgment, followed by an analysis of the extent to which the decision is consistent with existing case law authority in England. Finally, this commentary concludes with a consideration of the potential implications that the ruling may have on developers and decision-makers

Congregational boundaries, new church developement and congregational relationships within the Dutch reformed church

In this article it is argued that in any system in which membership of a particular congregation is determined by the members themselves through subjective criteria, the relationship between congregations is influenced detrimentally. Subjective criteria are the opposite of objective criteria such as geographical boundaries or different language groups. The same is true when a congregation is not respected as God’s complete church. Beside this, subjective criteria also question God’s providence and also the essential variety of God given gifts that should be present in the congregation in order to function as a complete and healthy Body of Christ. New church development has to take all this into consideration when churches for different culture and generation groups are planted within the borders of existing congregations. It is, after all, not context that is the norm for the church, but God Himself through his Word and Spirit

Censorship in Cyberspace: Closing the Net on "Revenge Porn"

The article reviews current privacy laws in the context of “Revenge Porn”. Given the speed at which images are published online, the article highlights the futility of breach of confidence and other civil actions in preventing publication at the outset. Furthermore, private law is expensive offering little protection against the victim’s humiliation. The article proposes that non-consensual pornography should be criminalised under the Coroners and Justice Act 2009 by way of a Statutory Instrument: Misuse of Private Information 2014

Translating the fashion story: analyzing fashion captions in two women\u27s magazines

Fashion magazines are the most accessible source for women to learn the latest about fashion and trends. Publishing company Condé Nast owns many consumer fashion magazines including the American editions of Lucky and Vogue. Even though both magazines are classified under the genre of fashion, these magazines are branded differently. Vogue features editorial styling, which is garments arranged lavishly and creatively for the glossy fashion spreads. However, Lucky magazine contains both editorial and lifestyle styling. To reinforce the styled image, fashion magazines place captions in these editorials. Captions transform these garments into written language. Since each magazine uses different types of styling, editors are writing captions in different formats. The purpose of the study is to investigate the stylistic similarities and differences of fashion captions in Lucky and Vogue. Additionally, semantic-syntax tree diagrams were used to determine how the fashion captions communicate meaning. This study followed a mixed methods approach using a purposive sample (n=14). The March and September issues were examined from 2010-2013. Data results show magazines are written primarily in grammatical modifiers. Different from prior research, nouns were the largest category, and adjectives composed the second largest category. Some captions did not have verbs resulting in mainly a descriptive narrative. Each magazine differed in the types of verbs used, frequency of proper nouns, and types of prepositions. Furthermore, when editors are not telling a ‘fashion story’, then captions are written as imperative commands. When telling a ‘fashion story’, the garment is often personified to take on human characteristics or described as possessing certain characteristics. Both magazines use these writing styles to convey different ideas and content to the reader. The results of this study strengthened the belief that a distinct stylistic form of writing exists in fashion captions. From this study, fashion editors and scholars may become more aware of the current stylistic formations featured in fashion captions, and further enhance their knowledge of how to communicate editorial trends and themes to their intended audience

Initialer Streuabbau und Enzymkinetik in Abhängigkeit von Streuqualität und Landnutzungsintensität

Extrazelluläre hydrolytische Enzyme (EHEs), die überwiegend von Bodenmikroorganismen produziert werden, übernehmen eine wichtige Rolle beim Umsatz der organischen Substanz im Boden. Die Auswirkungen von unterschiedlicher Landnutzungsintensität (Düngung, Beweidung, Mahd) in Grünlandflächen auf Enzymkinetiken und die von Ihnen gesteuerten Abbauraten organischer Substanz sind allerdings kaum untersucht (Tischer et al. 2015). Als Kenngrößen des katalytischen Verhaltens von EHEs können die limitierende Umsatzrate (Vmax) sowie die apparente Substrataffinität (Km) mittels der Michaelis-Menten Gleichung angenähert werden. Um den Einfluss unterschiedlicher Streuqualität auf Interaktionen zwischen verschiedenen Enzymen zu testen wurden Teebeutel mit grünem Tee (C/N Verhältnis 12) und Teebeutel mit Rooibos-Tee (C/N Verhältnis 43) in Anlehnung an Keuskamp et al. (2013) für drei Monate auf je 25 unterschiedlich intensiv bewirtschafteten Grünland-Flächen der DFG-Biodiversitätsexploratorien (Hainich, Schorfheide) eingebracht. In den ausgebrachten, 3-monatig-exponierten, Teeproben und in angrenzenden Bodenproben wurden die katalytischen Eigenschaftenvon drei EHEs die am Abbau von Zellulose beteiligt sind, von Hydrolasen aus dem N- und P-Kreislauf sowie die Enzymaktivitäten von Phenol- und Peroxidasen erfasst (Tischer et al. 2015). Die bisherigen Ergebnisse der Studie zeigen deutlich enge Beziehungen zwischen den Kinetiken der Hydrolasen und ökosystemrelevanten Funktionen wie dem Streuabbau und weisen zudem auf die kinetischen Zusammenhänge und Limitierungen unterschiedlicher Enzymsysteme im Abbau von Streu hin. Die Landnutzungsintensität scheint in ersten Auswertungen neben der Streuart ein weiterer Hauptfaktor für die Abbaudynamik und die Beziehungen zu den Enzymkinetiken zu sein