The use of fly ash from the combustion of poultry litter for the adsorption of chromium(III) from aqueous solution

Fly ash, from the combustion of poultry litter, was assessed as an adsorbent for chromium(III) from aqueous solution. The adsorption process was studied as a function of temperature and time. Adsorption was best described by the Langmuir model. The adsorption of chromium(III) on the fly ash was endothermic and kinetic studies suggest that the overall rate of adsorption was pseudo‐second order. At low initial concentrations film diffusion effects contribute to limiting the overall rate of adsorption while at higher initial chromium(III) concentrations pore diffusion becomes more important. An adsorption capacity of 53 mg dm^?3 was reached at 20 °C. © 2002 Society of Chemical Industry     

Variables and Behavior.

Comments on an article by Breland and Breland (Amer. Psychologist, 1961, 16, 681-684), stating that the authors have reported "egregious failures" to maintain some types of conditioned behavior. They attribute their failures to the prepotency of instinctive behavior over conditioned behavior. The commentator states that it is difficult to interpret most of their observations because their article has omitted relevant procedural details; however, it is clear that most of their procedures involve chains of behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electron capture dissociation and 13C,15N depletion for deuterium localization in intact proteins after solution-phase exchange

For localization of deuterium atoms after solution-phase exchange with D2O, intact proteins are often digested prior to analysis by mass spectrometry (MS) and tandem MS (MS/MS). Amelioration of limitations associated with this approach (e.g., <70% sequence coverage and some D atom scrambling during MS/MS) were sought using intact proteins and two newer methods applied to tracking H/D exchange dynamics for the first time. Using 2-4-fold signal enhancements through depletion of 13C and 15N isotopes and implementing the new MS/MS technique of electron capture dissociation (ECD) yielded an increased number of c and z* ions observed (43 vs 25) for recombinant yeast ubiquitin (9.3 kDa). Initial determination of D atom content in consecutive c ion series (c4-c7, c28, c31, c32, and c33) was demonstrated. The improved ion signal and experiment speed combined with narrower isotopic distributions markedly increases the degree of localization and feasibility of ECD-based MS/MS after solution-phase H/D exchange.     

Retrieval of stratospheric aerosol size and composition information from solar infrared transmission spectra

Infrared transmission spectra were recorded by the Jet Propulsion Laboratory MkIV interferometer during flights aboard the NASA DC-8 aircraft as part of the Airborne Arctic Stratospheric Expedition II (AASE II) mission in the early months of 1992. In our research, we infer the properties of the stratospheric aerosols from these spectra. The instrument employs two different detectors, a HgCdTe photoconductor for 650-1850 cm(-1) and an InSb photodiode for 1850-5650 cm(-1), to simultaneously record the solar intensity throughout the mid-infrared. These spectra have been used to retrieve the concentrations of a large number of gases, including chlorofluorocarbons, NOy species, O3, and ozone-depleting gases. We demonstrate how the residual continua spectra, obtained after accounting for the absorbing gases, can be used to obtain information about the stratospheric aerosols. Infrared extinction spectra are calculated for a range of modeled aerosol size distributions and compositions with Mie theory and fitted to the measured residual spectra. By varying the size distribution parameters and sulfate weight percent, we obtain the microphysical properties of the aerosols that best fit the observations. The effective radius of the aerosols is found to be between 0.4 and 0.6 microm, consistent with that derived from a large number of instruments in this post-Pinatubo period. We demonstrate how different parts of the spectral range can be used to constrain the range of possible values of this size parameter and show how the broad spectral bandpass of the MkIV instrument presents a great advantage for retrieval ofboth aerosol size a nd composition over instruments with a more limited spectral range. The aerosol composition that provides the best fit to the measured spectra is a 70-75% sulfuric acid solution, in good agreement with that obtained from thermodynamic considerations.     

Development and qualitative assessment of the GAME/sup Cycle/ exercise system

Increased physical activity is important for reducing the risk of cardiovascular disease. However, among people with disabilities, inactivity is prevalent. In order to encourage exercise among members of this group, an exercise system combining arm ergometry with video gaming, called the GAME/sup Cycle/ was previously developed. User input was received through an arm crank ergometer on a swivel, with the angular velocity of the ergometer resistance wheel controlling one axis and rotation of ergometer about the swivel controlling the other. The purpose of this study was to detail the algorithms used in this device and present novel features included in a second generation of the GAME/sup Cycle/. The features include a wheel on base, a steering return mechanism, and wireless fire buttons. A focus group of clinicians (n=8), wheelchair users (n=8), and clinician wheelchair users (n=2) was conducted to evaluate the features of the GAME/sup Cycle/. The focus group suggested improvements to the steering mechanism and to reduce vibration in the system. However, the focus group enjoyed the GAME/sup Cycle/ and felt that it would encourage exercise among persons with disabilities.     

The hydrolytic stability of some commercially available polycarbonates

A number of commercially available polycarbonates, including formulations made flame retardant by two different modifications, have been exposed to conditions producing moderately rapid hydrolysis. Hydrolysis rates were calculated from molecular weight data determined by gel permeation chromatography and, in some cases, from melt flow rate data. The rates calculated by the two methods are in good agreement. In general, the standard formulations containing minimal additive packages are the most hydrolytically stable. Although one relatively new flame retardant polycarbonate demonstrates generally good resistance to hydrolysis, most of the flame retardant formulations appear to be quite susceptible to hydrolytic degradation. For these materials, hydrolysis under conditions encountered in use could cause significant decreases in impact strength within a few years.     

Thermal and photo-oxidation of polysulfone

Prolonged heating at temperatures below 140°C. causes only slight changes in the properties of polysulfone. Exposure to ultraviolet light, however, results in substantial changes as evidenced by broad absorption in both the hydroxyl and carbonyl regions of the infrared spectrum, evolution of carbon monoxide and dioxide, decrease in polymer elongation and intrinsic viscosity, and pronounced yellowing. A free-radical mechanism is proposed in which chain scission occurs with the formation of low molecular weight, oxidized fragments as the predominant oxidation products.     

Wax esters of barracudina lipid: A potential replacement for sperm whale oil

A sample of barracudina, a small fish potentially available in large quantities off Nova Scotia, contained 17.7% body lipid of which 10% was triglyceride and 85% wax ester. The triglyceride, of calculated iodine value 48, was unusually rich in 14:0 (25.8%), 18:0 (4.3%), 20:0 (1.19%), 22:0 (0.45%) and 24:0 (0.75%). The wax ester fatty acids had a calculated iodine value of 126 and a “normal” marine oil fatty acid composition. The wax ester fatty alcohols contained 42.2% hexadecanol, 29.5% octadecenols, 8.2% eicosenols and 3.8% docosenols. Certain interrelationships between fatty alcohols and fatty acids are indicated by details of composition. The potential exploitation of barracudina lipid as a substitute for sperm oil in some uses appears possible.     

A biopsychosocial formulation of pain communication.

We present a detailed framework for understanding the numerous and complicated interactions among psychological and social determinants of pain through examination of the process of pain communication. The focus is on an improved understanding of immediate dyadic transactions during painful events in the context of broader social phenomena. Fine-grain consideration of social transactions during pain leads to an appreciation of sociobehavioral events affecting both suffering persons as well as caregivers. Our examination considers knowledge from a variety of perspectives, including clinical health psychology, social and developmental processes, evolutionary psychology, communication studies, and behavioral neuroscience. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Pump wave coherence,modulation instability and their effect on continuous-wave supercontinua

The effect of pump coherence on the evolution of continuous-wave (CW) supercontinua is explored within the framework of the generalised nonlinear Schrödinger equation. Recent results of experimental studies, using an amplified spontaneous emission (ASE) based CW pump source, with a selectable coherence time, confirm the trend observed numerically [1]: an optimum degree of partial pump coherence generates the broadest spanning continuum. The effect of third order dispersion on continuum expansion is discussed in the context of an optimum degree of pump coherence. Finally, a design guideline for CW pumped supercontinuum light sources is suggested, relating the optimum pump bandwidth to the modulation instability period.