Recovery of gold cyanide using inherently conducting polymers

Removal of gold from basic solutions containing [Au(CN)₂]^? has been demonstrated using the inherently conducting polymer polypyrrole. Polymers containing sulfonated aromatic dopants have been found to display a significant ability to remove gold from such solutions. Experiments performed in solutions containing both gold and copper cyanide complexes indicate that the recovery process is not highly selective. However, the polypyrroles used display significantly faster rates of gold recovery than activated carbon. © 2003 Society of Chemical Industry     

Undesirable sensory properties of the dried pea (Pisum sativum). The rôle of saponins

The rôle of saponins in the undesirable sensory properties of the dried pea P sativum is reported. The sensory properties of isolated soyasaponin I are defined and described as bitter, astringent and metallic. The distribution of saponin in various air-classified pea flour fractions shows that the protein-rich fraction may contain sufficient saponin to cause undesirable tastes.     

Case study: paradoxical response to naltrexone treatment of self-injurious behavior

Opioid receptor antagonists have been studied in the management of self-injurious behavior (SIB) in developmentally disabled individuals. The authors present a case of a severely retarded, autistic man whose SIB increased dramatically during a trial of naltrexone. A paradoxical increase in SIB, attributed to the extinction burst phenomenon during the initial period of nonreward, is known to occur during treatment with naloxone, a short-acting parenteral opioid antagonist. It has only once been reported during treatment with naltrexone, a long-acting orally administered agent. Opioid analgesic effects and learning theory can explain both increases and decreases in SIB after opioid blockade.     

A reflective approach to career trajectory in advanced practice nursing

In response to a university mandate and general faculty dissatisfaction with work assignments, faculty developed a faculty work load formula. The authors discuss the development of the teaching portion of the formula. Implementation of the formula and publication of teaching work loads has resulted in greater awareness of other's responsibilities, improved faculty morale, increased accountability, and a greater sense of control. Some problem areas are also discussed.     

Some aspects of the analysis of coal by X-ray fluorescence spectroscopy

Bituminous coal samples from 84 distinct sources were analysed by conventional British Standards (BS) methods for phosphorus, sulphur, chlorine, ash and the ash-forming elements (calcium, silicon, aluminium, iron, sodium, magnesium, potassium, titanium and manganese). In most cases four determinations were made per element per source. Samples were crushed to ?212 μm (72 BS mesh) and pressed into aluminium cups at 20 t in^?2 (309 MPa) without binder or backing. Two pellets from each sample were analysed by wave-length dispersive X-ray fluorescence techniques, using a spectrometer equipped with a rhodium rube; the X-ray count took 60 s. The X-ray results were calibrated against the conventional results using multiple regression. The accuracy obtained was comparable with routine ‘wet chemical’ techniques. The X-ray technique is suitable for the routine determination of large numbers of samples.     

Lipids of seven cereal grains

Grain samples of representative varieties of barley, corn, oats, rye, sorghum, triticale, and wheat grown commercially in the north central US were analyzed. Chemical constituents of the varieties studied are presented to provide an overview of their characteristics. Lipids of the milled grain samples were solvent extracted, classified by silicic acid column chromatography, and separated by thin layer chromatography. Fatty acid composition of the total lipid was determined by gas liquid chromatography and the fatty acid content was determined by saponification and extraction. Total lipid content of the grains ranged from 2.3% for ‘Polk’ wheat to 6.6% for ‘Chief’ oats. Lipid composition varied considerably. The row crops, corn and sorghum, have a high neutral lipid and low glycolipid content. The small grain varieties have a more balanced distribution among neutral lipids, glycolipids, and phospholipids. Fatty acid composition of the total lipid was similar for all grains. Minor qualitative differences were noted among the lipid classes of the 7 cereals.     

Ultramicroscopy of association colloids formed from block copolymers

Ultramicroscopy studies have been made of micelle formation by two poly(styrene)-poly(isoprene) block copolymers in organic solvents (N,N-dimethylacetamide and n-decane respectively) and a poly(l-glutamic acid)-poly(l-leucine) block copolymer in an aqueous solution of 0.2M NaCl at pH = 4.0. The technique provides a method of determining the number-average translational diffusion coefficient) $\text{D}\text{?}{}_{\mathrm{n}}$, of association colloids and leads, via the Stokes-Einstein relation, to a measure of the number-average of the reciprocal hydrodynamic radius $\text{(R}{}_{\mathrm{<mtext>D</mtext><mtext>?</mtext>}}{}^1\text{)}{}_{\mathrm{n}}$ for spherical particles. Particles having a radius less than approximately 30 nm were too small to be detected by the technique.The ultramicroscopy results were compared with data obtained by laser light scattering photon correlation spectroscopy which provides a measure of the z-average translational diffusion coefficient. $\text{D}\text{?}{}_{\mathrm{z}}$. An additional comparison was made by carrying out measurements on two well-characterized poly(styrene/divinyl benzene) latices.