Development of Fuel Economy Gear Oil Technology

Vehicle fuel economy will continue to increase in importance as world vehicle production grows and fuel supplies become more limited year by year. As OEMs strive to produce cars and trucks with greater fuel efficiency and extended durability, additive technology developers are increasingly being asked to contribute to these goals from the lubricant side. Axle inefficiency can account for as much as 10% of the overall losses in an automotive driveline so improvements in axle efficiency can contribute greatly to improving vehicle fuel economy. For good durability, low axle oil operating temperatures are also needed to minimize oxidative and thermal degradation of the oil, reduce deposits and sludge formation, and extend oil drain intervals. To develop gear oils that can increase axle efficiency significantly while maintaining stable operating temperatures requires rig tests that are fast, precise and reproducible. This paper documents the development of a new axle test rig and test procedures and presents test results on several gear oils. The test results show the contributions of base oil viscosity, base oil chemistry, and additive chemistry on the fuel economy and temperature of the various oils. Having a dependable tool is enabling the development of new fuel-efficient and durable gear oil technology.     

Does Pheromone Biology of Lambdina athasaria and L. pellucidaria Contribute to Their Reproductive Isolation?

Recently, 7-methylheptadecane and 7,11-dimethylheptadecane have been reported as sex pheromone components of both spring hemlock looper (SHL), Lambdina athasaria, and pitch pine looper (PPL), Lambdina pellucidaria. Our objective was to test the hypothesis that SHL and PPL are reproductively isolated, in part, through species specificity in: (1) absolute configuration of pheromone components, (2) diel periodicity of pheromonal communication, and/or (3) seasonal flight period. In coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses of stereoselectively synthesized (7S)- and (7R)-7-methylheptadecane [7S; 7R] as well as (7S,11S)-, (7R,11R)-, and (meso-7,11)-7,11-dimethylheptadecane [7S,11S; 7R,11R; meso-7,11], only 7S and meso-7,11 elicited responses by male SHL and PPL antennae. In field experiments, male SHL and PPL were attracted only to lures containing 7S plus meso-7,11. In hourly recordings of trap-captured males, SHL and PPL in their respective habitats were trapped between 24:00 and 03:00 hr. Capture of both SHL and PPL in pheromone-baited traps throughout June indicated overlapping seasonal flight periods. These findings of identical absolute configuration of pheromoal components, diel periodicity of pheromonal communication, and overlap of seasonal flight periods support synonymy of SHL and PPL. Finite taxonomic classification of PPL and SHL must await careful assessment of further criteria, such as morphometrics, molecular comparisons and ecological analyses.     

Entrapment and displacement of nitrous oxide in a drained pasture soil

The objective of this work was to investigate a possible reason for the `unaccounted for ¹⁵N' fraction, of ¹⁵N mass balances, being so large in pasture systems, namely: the displacement and physical release of entrapped N₂O gas from within a soil profile. A soil core was placed inside a purpose built perspex glovebox and the internal N₂O concentration was continuously monitored. KNO₃ was applied followed by periodic applications of distilled water. After 256 h the soil core was physically broken open in an attempt to release any N₂O which may have been entrapped in the soil core. Instantaneous increases in glovebox N₂O concentrations occurred when surface applied water displaced N₂O from the base of the soil core and when the soil core was broken open (equal to 9.5% of N applied). The relative contribution these two mechanisms make will depend on the concentration of denitrification products present, the frequency and volume of irrigation/rainfall and the duration of the experiment.     

Anisotropic core–shell nanocomposites by direct covalent attachment of a side-functionalized poly(3-hexylthiophene) onto ZnO nanowires

Inorganic-organic hybrid solar cells have demonstrated great potential for the development of next generation flexible electronics to deliver efficient energy conversion. The interfacial morphology and structure between donor and acceptor are determinative to the device performance. Here, we report on novel core–shell hybrid heterojunction nanostructures by covalently grafting side-functionalized poly(3-hexylthiophene) onto ZnO nanowires without ligand linkers. Solvatochromism of polythiophene is utilized to control the polymer morphology at interface. Study into the photophysics of nanohybrids demonstrates an elongated conjugation length of the polymer backbone at the interface and fast interfacial charge transfer. These results provide critical insight into the utilization of molecular composites to control donor–acceptor interfaces and further enable the use of anisotropic nanohybrids as photovoltaic elements for the massive fabrication of high efficiency devices.     

Labeling of Phosphatidylinositol Lipid Products in Cells through Metabolic Engineering by Using a Clickable myo-Inositol Probe

Phosphatidylinositol (PI) lipids control critical biological processes, so aberrant biosynthesis often leads to disease. As a result, the capability to track the production and localization of these compounds in cells is vital for elucidating their complex roles. Herein, we report the design, synthesis, and application of clickable myo-inositol probe 1 a for bioorthogonal labeling of PI products. To validate this platform, we initially conducted PI synthase assays to show that 1 a inhibits PI production in vitro. Fluorescence microscopy experiments next showed probe-dependent imaging in T-24 human bladder cancer and Candida albicans cells. Growth studies in the latter showed that replacement of myo-inositol with probe 1 a led to an enhancement in cell growth. Finally, fluorescence-based TLC analysis and mass spectrometry experiments support the labeling of PI lipids. This approach provides a promising means for tracking the complex biosynthesis and trafficking of these lipids in cells.     

Recent advances in drug delivery systems based on polypeptides prepared from N‐carboxyanhydrides

Recent years have seen a dramatic increase in interest in the use of ring‐opening polymerization of N‐carboxyanhydride monomers as a method to prepare well‐defined polypeptides and peptide hybrid materials. The resulting molecules are often capable of assembling into a variety of different structures, including micelles, vesicles, nanoparticles and hydrogels, and therefore have been explored as novel drug delivery systems. Peptides are attractive in this regard due to their rich chemical functionality and ability to assemble through the formation of secondary structures (e.g. α‐helices and β‐sheets). In addition, they are inherently biodegradable and biocompatible. This review describes recent advances in the field, covering aspects such as improved methods with which to prepare better‐defined polypeptides, crosslinking of assemblies to enhance biostability, the preparation of materials that respond to a variety of stimuli (including light and intra‐ or extracellular redox conditions), functionalization with targeting ligands to enhance cellular uptake, assemblies for small interfering RNA delivery and approaches to theranostic systems. © 2014 Society of Chemical Industry     

Older but wilier: In-group accountability and the development of subjective group dynamics.

To test social and cognitive variables that may affect the development of subjective group dynamics, the authors had 224 children between the ages of 5 and 12 years evaluate an in-group and an out-group and normative and deviant in-group members under conditions of high or low accountability to in-group peers. In-group bias and relative favorability to normative versus deviant in-group members (differential evaluation) increased when children were accountable to peers and as a function of perceptions of peer group acceptance of these members (differential inclusion). These effects were significantly larger among older children. Multiple classification ability was unrelated to judgments of group members. This study shows that the development of subjective group dynamics involves an increase in sensitivity to the normative aspects of the intergroup context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A DISTRIBUTED PARAMETER APPROACH TO THE DYNAMICS OF ROTARY DRYING PROCESSES

ABSTRACT

A nonequilibrium distributed parameter model for rotary drying and cooling processes described by a set of partial differitial equations with nonlinear algebraic constraints is developed in this work. These equations arise from the multi–phase heat and mass balances on a typical rotary dryer. A computational algorithm is devekped by employing a polynonial approximation ( orthogonal collocation) with a glotal splinc technique leading to a differential–algebraic equation ( DAE) system. The numerical solution is carried out by using a standard DAE solver.

The two– phase–flow heat transfer coelficient is computed by introducing a correction factor to the commonly accepted correlations. Since interaction between the falling particles are considered in the correction factor,the results are more reliable than those computed by assuming that heat transfer between a single falling particle and the drying air is unaffected by other particles. The heat transfer computations can be further justified via a study on the analogies between heat and mass transfer.

The general model devloped in this work is mathematically more ritorous yet more flexible that the lumped parameter models established by one of the authors (Douglas et al., (1993)). The three major assumptions of an equilibrium operation, perfect mixing and constant drying raic, are removed in the distributed parameter model.

The simulation results are compared with the operational data from an industrial sugar dryer and predictions from earlier models. The model and algorithm successfully predict the steady state behaviour of rotary dryers and collers. The generalized model can be applied to fertilizer drying processes in which the assumption of constant drying rate is no longer valid and the existing dynamic models are not applicable.     

Further Theoretical Studies on Rotary Drying Processes Represented By Distributed Systems

ABSTRACT

Mathematical tools for studying panicle transpon in rotary drying and cooling processes are developed in this paper. In contrast to conventional approaches aimed at deriving empirical or xmi-empirical correlations, a rigorous mathematical analysis which employs dilferential calculus and analytical geometry is emphasis4 in the current research. These developments allow accurale computations of solid flowrate, retention time and particle holdup in rotary dryers with arbilrary flight configurations. Consequently, optimal dryer configuration design in terms of drum dimension, flight number and geometry can be achieved through a better understanding of the mathematical insight of rotary drum performance.

Techniques developed using this method are applied to the distributed parameter model eslablished earlier by the authors (Wang el al., 1993) to replace out-dated correlations for the determination of retention Lime and solid holdup. As a result of the new developments, the distributed parameter approach to the dynamics of rotary drying processes becomes more general and more reliable.     

Effect of betaine supplementation on plasma nitrate/nitrite in exercise-trained men

Background  

Betaine, beetroot juice, and supplemental nitrate have recently been reported to improve certain aspects of exercise performance, which may be mechanistically linked to increased nitric oxide. The purpose of the present study was to investigate the effect of betaine supplementation on plasma nitrate/nitrite, a surrogate marker or nitric oxide, in exercise-trained men.