Occurrence and Preclusion of Terpene Chlorohydrins in Citrus Essential Oils

ABSTRACT: Screening commercial cold-pressed oils revealed the presence of terpene chlorohydrins, which may have quality and safety implications for end-users. Concentrations of (1R, 2R, 4R)-2-chloro-8- p -menthen-1-ol in some citrus essential oils ranged from less than 1 to 140 ppm. More than half of the oils tested contained less than 2 ppm of (1R, 2R, 4R)-2-chloro-8- p -menthen-1-ol. A pilot plant study used different concentrations of chlorinated water during the oil-recovery process. Cold-pressed oil, produced from a 30-ppm chlorine solution, contained (1R, 2R, 4R)-2-chloro-8- p -menthen-1-ol at detection threshold. The presence of (1R, 2R, 4R)-2-chloro-8- p -menthen-1-ol in citrus essential oils results from processing conditions and can be reduced through the reduction of chlorine levels in treatment water.     

Capillary rise in porous,fibrous media during liquid immersion

The modified Washburn equation has been further developed in this work, to examine capillary rise in porous media which are being immersed in liquid at a continuous rate. The capillary rise rate and/or properties of the media can be determined by a series of differential equations which govern the processes. The model was applied to oleophillic and oleophobic porous, fibrous media with generally good results, however it was found that the model needed to be fitted separately to the initial rise phase and to the longer-term (near-constant slope) phase. It was also found that a good agreement between the theory and experiment could be found if the porous media was contained inside a glass tube so that inflow could only occur from below and not from the sides of the filter. In order to model the insertion of media without this tube, a combination of a horizontal and a vertical capillary model was needed. The model could not be easily fitted to very thin, oleophillic media, and reasons for this are discussed; one likely reason being the inflow of liquid from the sides of the media. However, good agreement between the model and experiment could be found for equivalent media with an oleophobic coating and the same oil.     

Preparation of asymmetric perovskite-type membranes by a settlement method

Asymmetric SrCe_0.95Yb_0.05O_3?α (SCYb) membranes were prepared by using a settlement method to deposit a thin dense SCYb layer on the green porous SCYb support, followed by conventional dry pressing and co-sintering. SCYb powder was mixed in a liquid media (isopropanol) and directly poured onto the pre-pressed green porous SCYb support placed in a beaker. After the powder fully settled onto the support, the green asymmetric sample was dried and co-sintered. The cross-sectional images of the asymmetric systems indicate that thin dense SCYb films in the asymmetric membranes had uniform thicknesses at this level of analysis and show excellent adhesion to the porous support without any undesirable defects, delamination or cracking. Further, different dense layer thicknesses (80–20 μm) were readily obtained by altering the amount of the SCYb powders in the liquid media. The minimum dense layer thickness obtained by the settlement method, with the synthesis conditions utilised in this study, was around 20 μm.     

High-power pulsed and c.w. silicon double-drift IMPATT amplifiers at X-band

The letter presents some reflection-amplifier results for Si double-drift pulsed and c.w. IMPATTs. Peak r.f. powers of up to 11.6 and 16.5 W with instantaneous (?1 dB) bandwidths ~20% at gains >6 dB have been obtained at 10 GHz with 1- and 2-diode combinations when bias modulated with a pulsewidth of 4 ?s and p.r.f. of 1 kHz. A 2-diode c.w. combination has given a power of 7 W (c.w.) at 10.7 GHz with a gain of 6.5 dB and instantaneous (?1 dB) bandwidth of 400 MHz.     

The Bitwise Hashing Trick for Personalized Search

Many real world problems require fast and efficient lexical comparison of large numbers of short text strings. Search personalization is one such domain. We introduce the use of feature bit vectors using the hashing trick for improving relevance in personalized search and other personalization applications. We present results of several lexical hashing and comparison methods. These methods are applied to a user’s historical behavior and are used to predict future behavior. Using a single bit per dimension instead of floating point results in an order of magnitude decrease in data structure size, while preserving or even improving quality. We use real data to simulate a search personalization task. A simple method for combining bit vectors demonstrates an order of magnitude improvement in compute time on the task with only a small decrease in accuracy.     

Amino acids of citrus seed meal

Defatted seed meal from oranges and grapefruit contained more sulfur amino acids but less lysine than some common oilseed proteins. Grapefruit seed meal had less tryptophan and more sulfur amino acids than orange seed meal. Probable annual yields of Florida citrus seed oil, meal and hulls are 17, 23 and 13 million lb, respectively. Florida Agricultural Experiment Station Journal Series No. 4313.     

Model for Gas‐Liquid Flow through Wet Porous Medium

A method involving bubbling of air through a fibrous filter immersed in water has recently been investigated (Agranovski et al. [1]). Experimental results showed that the removal efficiency for ultra‐fine aerosols by such filters was greatly increased compared to dry filters. Nuclear Magnetic Resonance (NMR) imaging was used to examine the wet filter and to determine the nature of the gas flow inside the filter (Agranovski et al. [2]). It was found that tortuous preferential pathways (or flow tubes) develop within the filter through which the air flows and the distribution of air and water inside the porous medium has been investigated. The aim of this paper is to investigate the geometry of the pathways and to make estimates of the flow velocities and particle removal efficiency in such pathways. A mathematical model of the flow of air along the preferred pathways has been developed and verified experimentally. Even for the highest realistic gas velocity the flow field was essentially laminar (Re ≈ 250). We solved Laplace's equation for stream function to map trajectories of particles and gas molecules to investigate the possibility of their removal from the carrier.     

Application of socio-technical systems models to Martian colonisation and society build

Abstract

The human desire for exploration, together with an increasingly demanding potential need for establishing a human colony away from Earth has stimulated the concept and early planning for Mars colonisation. Successful delivery of such a challenging and expensive technological feat requires a highly informed and supportive general society. Although the ergonomic constraints on astronauts living and working in space is well documented, no study has employed the use of ergonomics tools to explore colony and societal build on other worlds. We have employed Cognitive Work Analysis to derive an abstraction hierarchy for both colony establishment and maintenance with the vision of building a new Martian society. We find that our model will accommodate five major challenge themes collected from over 800 members from twenty two United Kingdom - based astronomical societies and scientific groups and propose that this study may have utility in guiding mission planners in the early colonisation phase and later stage expansion processes. Using the proposed architecture for the Mars One mission, we have performed a basic human factors analysis and propose a number of key design features which may enable long term habitation.