Ethyl propionate: Synergistic kairomone for african palm weevil,Rhynchophorus phoenicis L. (Coleoptera: Curculionidae)

Small trunk pieces of a freshly felled 10-year-old oil palm,Elaeis quineensis (Jacq.), were placed in a modified Nalgene desiccator, and volatiles captured for six days on Porapak Q. Gas chromatographic (GC) analysis of Porapak-Q-trapped volatiles with both flame ionization (FID) and electroantennographic detection (EAD) using male or femaleR. phoenicis antennae revealed several EAD-active compounds. They were identified as: ethyl acetate, ethyl propionate, isobutyl propionate, ethyl butyrate, and ethyl isobutyrate. In field experiments in the La Me Research Station, Côte d'Ivoire, ethyl propionate (50 mg/24 hr) but not all esters combined (50 mg/24 hr each) significantly increased capture ofR. phoenicis in pheromone-baited (3 mg/24 hr) traps. One kilogram of 1- to 3-day-old palm tissue was significantly more effective than ethyl propionate in enhancing pheromone attraction. Superior attraction of palm tissue may be attributed to additional as yet unknown semiochemicals. Alternatively, release rates and/or ratios of synthetic volatiles differed from those of palm tissue at peak attraction.     

Electrochemical aspects of display technology based on nanostructured titanium dioxide with attached viologen chromophores

Progress in recent years in the field of electrochromic displays based on viologen modified high-surface area TiO₂ electrodes (Vio²⁺/TiO₂) has moved the technology towards commercialisation. Viologen molecules (Vio²⁺), derivatised with phosphonic acid attachment groups can be chemisorbed on nanostructured TiO₂ layers of thickness 2-10 μm. Characterisation by cyclic voltammetry, spectroelectrochemistry and impedance spectroscopy demonstrates that colourless Vio²⁺/TiO₂ is reversibly reduced to the strongly coloured cation radical species Vio⁺/TiO₂. This system can constitute the working electrode of an electrochromic display with a capacitive doped SnO₂ electrode as counter electrode, the latter coated by an electrochemically inert white light-reflecting layer. Such a device is stable upon repeated colouration-bleaching cycles with a bleached-to-coloured state contrast ratio exceeding 5. Multicolour displays can be achieved by patterning different electrochromophores onto different areas of one working electrode.     

Vergleichende spannungsoptische Untersuchungen und Fließversuche unter konzentriertem Druck

Ohne Zusammenfassung     

Psychological Treatments for Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis.

This study conducted a systematic review to assess the quality of existing literature on psychological treatments for irritable bowel syndrome and to quantify the evidence for their efficacy. Three independent reviewers (2 from England, 1 from the United States) coded the quality of 32 studies, 17 of which provided data suitable for meta-analysis. Meta-analysis of efficacy data (50% reduction of symptoms) gave an odds ratio of 12 (95% confidence interval = 5.56-25.96) and a number needed to treat of 2. Psychological treatments are, as a class of interventions, effective in reducing symptoms compared with a pooled group of control conditions. Questions regarding the relative superiority of specific psychological treatments and influence of active versus nonspecific treatment effects remain unanswered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Studies on vaporization and halogen decomposition of methyl mercury compounds using gc with a microwave detector

Gas chromatography with the very sensitive microwave emission spectrometric detector has been used to study the distribution of (CH₃)₂Hg between air and water and the vapor pressures above CH₃HgX compounds and their solutions, where X designates (Cl, Br, I or OH). The distribution coefficient for (CH₃)₂Hg is 0.31 at 25°C and 0.15 at 0°C which shows that this compound will be readily lost to the atmosphere above natural waters. The vapor pressures of CH₃HgCl(s) and CH₃HgOH(s) are l l and 5.6 μ of Hg respectively at 22°C. The volatility of monomethyl mercury above water solutions as a function of pH can be interpreted in terms of the known equilibria occurring in the water phase.Very rapid photochemical reactions of CH₃HgX with I₂ or Br₂ at very low concentrations were discovered in water at room temperature. Such reactions offer a potential means for the destruction of CH₃HgX from laboratory or industrial discharges. In addition the reaction with I₂ is an important potential source of error in analytical procedures utilizing the high extractability of the CH₃HgI species. The reaction produces CH₃I and HgI₂(s) and is first-order in the concentrations of both the CH₃HgCl and I₂.     

Incorporating end-user models and associated uncertainties to investigate multiple stakeholder preferences in system design

The essence of systems engineering lies in enabling rational decision-making that is consistent with the preferences of the system’s stakeholders. Modern approaches, such as value-driven design, attempt to convey the true preferences of the stakeholder using mathematical formulations like value models. A critical step to the formation of value models is the identification of the stakeholders. A primary stakeholder must be identified and then it must be determined how the other stakeholders’ preferences impact the preference of the primary, if they do at all. This paper looks at three stakeholders of an electric vehicle system, all of which could be considered the primary stakeholder dependent on the situation. Novel customer, commercial, and government-oriented value models are created. To understand the impact of customers on the primary stakeholder’s designs, an end-user value-based demand model is developed and a method for integrating end-user preferences into the manufacturer’s value model is demonstrated. Uncertainties associated with the end-users, including those associated with the economy, are quantified and incorporated into a value-based design framework through Monte Carlo simulations. Possible stakeholder risk attitudes are discussed and a rational decision-making strategy to maximize stakeholder’s system value under uncertainty is presented. The resulting designs and the influences of the multiple stakeholders are discussed, showing that the identification and incorporation of the important stakeholders are critical to the systems engineering process and value-based design in particular.     

The hydrolysis of iodine: Equilibria at high temperatures

The hydrolysis (or disproportionate) of molecular iodine to form iodate and iodide ions has been studied by emf measurements over the temperature range, 3.8 to 209.0°C. The interpretation of these results required a knowledge of the formation constant for triiodide ion and the acid dissociation constant of iodic acid, both of which were measured as a function of temperature. The resulting thermodynamic data have been incorporated into a general computer model describing the hydrolysis equilibria of iodine as a function of initial concentration, pH and temperature.