Green Coatings Research Articles

Poly(o-toluidine) coatings on low carbon steel: synthesis and characterisation

Poly(o-toluidine) (POT) coatings have been synthesised on low carbon steel (LCS) substrates by the electrochemical polymerisation (ECP) of o-toluidine in an aqueous solution of oxalic acid under galvanostatic conditions. Uniform and strongly adherent dark green POT coatings were obtained on LCS substrates. These coatings were characterised by potential - time E-t curves, ultraviolet (uv) visible absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). It was found that oxalic acid is a suitable medium for the ECP of o-toluidine on an LCS substrate, and the electrochemical growth process is characterised by three distinct stages: dissolution of the LCS electrode surface and formation of iron oxalate interphase, complete passivation of the LCS electrode surface and decomposition of the interphase, followed by ECP of o-toluidine. The induction time was observed to decrease with an increase in applied current density. An optical absorption spectroscopy study revealed exclusive formation of the insulating pernigraniline base (PB) form of POT at a lower current density, whereas at a higher current density the coating comprised a mixed phase of conducting emeraldine salt (ES) and PB forms. The FTIR spectroscopy indicated the formation of a POT coating. The surface morphology of the POT coating was observed to depend on the applied current density, and it improved with an increase in current density.

Wet chemical deposition of ATO and ITO coatings using crystalline nanoparticles redispersable in solutions

The deposition of SnO2:Sb (ATO) and In2O3:Sn (ITO) transparent conducting coatings on glass substrate has been demonstrated by many techniques such as CVD, sputtering, vacuum deposition and sol-gel process. This paper presents an alternative process for the deposition of such coatings at room temperature by spin, dip and spray coating techniques using solutions prepared with crystalline nanoparticles fully redispersed in water (for ATO, ITO) or alcohol (for ITO) with solid contents up to 10–15 Vol.%, respectively. The deposited green coatings have been sintered at temperature as high as 900°C. In2O3:Sn coatings have a resistivity of 1.5×10−2 Ω cm as sintered and 3.4×10−3 Ω cm after annealing in nitrogen atmosphere. The resistivity of ATO single coatings shows a minimum ρ=1.7×10−2 Ω cm after annealing at 550°C. SnO2:Sb coatings present long term stability but the resistivity of annealed ITO coatings steadily increases with time to a value three times higher. All coatings have a high optical quality with transmission in the visible range larger than 90%.

Diamantes de capa verde: freqüência, distribuição e possível origem nos depósitos diamantíferos de Minas Gerais

Diamantes mostrando uma ínfima película verde, na forma de manchas irregulares, conhecidos como diamantes de "capa verde", são comuns principalmente em certos depósitos sedimentares de Minas Gerais. Cristais de diamante com essas características foram estudados nas mais importantes áreas produtoras da Província Diamantífera do Espinhaço e, comparativamente, na região de Coromandel. A freqüência de diamantes com capa verde nesses depósitos varia em percentagens, mas elas são relativamente altas na Província do Espinhaço, onde mostram valores sempre superiores a 25%, podendo localmente alcançar 90%. De outra forma, na região de Coromandel, este valor é inferior a 0,5%. São discutidas as duas principais hipóteses para a origem da capa verde: irradiação in situ a partir de minerais radioativos, ou presença de certos elementos cromóforos na parte mais externa dos cristais. A análise dos dados, porém, mostrou que existe uma associação entre os dois fatores, restando determinar a contribuição relativa de cada um deles na intensidade da pigmentação verde.

Red light on Calcutta; health via schools in Andhra Pradesh

UKs Overseas Development Administration (ODA) is supporting a project in a Calcutta slum (Sonagachi) where sex workers trained in prevention of sexually transmitted diseases (STDs) including HIV distribute condoms to other sex workers and educate them about STD/HIV prevention. Their green coat designates their status. They work out of a small clinic in Sonagachi which maintains the records and provides inexpensive diagnosis and treatment. Condom use among sex workers has increased from 2.7% to 67.8%. The public health specialist heading up the project hopes that the triple approach (peer education STD treatment and condom distribution) will keep HIV infections at their current low level (1-2%). He and his colleagues are evaluating this approach in five other red light districts of Calcutta. ODA also supports the Andhra Pradesh School Health Project. It involves the training of primary school teachers and multipurpose health workers development of a health curriculum a loan plan for furnishing health workers with mopeds and medicine kits for schools. Project-related research includes effectiveness of teachers as health promoters and evaluations of salt fortified with iodine and iron and water fluoridation. If this projects evaluation is good it will need a new headquarters in Hyderabad. Both projects emphasize good record keeping and evaluation.

Incomplete Digestion of Legume Starches in Rats: A Study of Precooked Flours Containing Retrograded and Physically Inaccessible Starch Fractions

The digestibility of starch in precooked flours from green coat lentils (Lens culinaris Medik) and red kidney beans (Phaseolus vulgaris L.) was investigated by balance experiments using rats treated with antibiotics to suppress hind-gut fermentation. The legume preparations were rich in intact cells filled with denaturated starch and contained retrograded amylose. Between 8% (beans) and 11% (lentils) of the total starch ingested appeared in the feces, indicating a relatively low starch digestibility. Red bean flours of two different particle sizes were similarly digested. Sixty percent of the fecal starch in the bean-fed animals and 70% in the lentil-fed group was retrograded amylose. The in vitro indigestible starch content of the flours was evaluated with three different methods that gave rather different values. The retrograded amylose fraction, measured after alkaline treatment of a dietary fiber residue obtained by enzymic digestion, was quantitatively recovered in the feces. None of the procedures gave accurate estimates of the total in vivo indigestible starch. Fecal excretion of starch in rats not treated with antibiotics indicated that the indigestible starch in lentils was less susceptible to fermentation than that in the red bean preparations.

Additional Genes for Green Seed Coat in Soybean

Determinisme genetique de la couleur de l'enveloppe de la graine chez le soja etudie a l'aide de 6 croisements sur 3 generations

亜鉛めっきの高耐食性緑色クロメート処理

亜鉛めっきの高耐食性緑色クロメート処理

THE PRECOCIOUS THREE-YEAR-OLD LORD MACAULEY

Thomas Babington Macaulay (1800-1859), historian, poet, essayist, and statesman, will most likely be remembered by American readers as the author of Lays of Ancient Rome. Macauley's precocity as a small child was vividly described in Sir George Trevelyan's The Life and Letters of Lord Macauley (1876) as follows: From the time that he was three years old he read incessantly, for the most part lying on the rug before the fire, with his book on the ground, and a piece of bread and butter in his hand. A very clever woman who then lived in the house as a parlour-maid told how he used to sit in his nankeen frock, perched on the table by her as she was cleaning the plate, and expounding to her out of a volume as big as himself. He did not care for toys, but was very fond of taking his walk, when he would hold forth to his companion, whether nurse or mother, telling interminable stories out of his own head, or repeating what he had been reading in language far above his years. His memory retained without effort the phraseology of the book which he had been last engaged on, and he talked, as the maid said, ‘quite printed words’, which produced an effect that appeared formal, and often, no doubt, exceedingly droll. About this period his father took him on a visit to Lady Waldegrave at Strawberry Hill, and was much pleased to exhibit to his old friend the fair bright boy, dressed in a green coat with red collar and cuffs, a frill at the throat, and white trousers.

Possible origins of α-damage in diamonds from kimberlite and alluvial sources

SummaryHeating experiments provide strong evidence that the transparent green coats on some diamonds from each of many localities are caused by α-particle irradiation after kimberlite injection and subsequent cooling. The natural diamonds with more or less homogeneous transparent green coats, studied in this work, appear to have received doses of at least 5 × 1013−1 × 1014 α.cm−2. For Pre-Cambrian kimberlites, such doses could occur if certain regions of the diatremes contained ⩾20 ppm by weight of equivalent uranium, after kimberlite injection and solidification.Such considerations lead to the prediction that the radioelement concentrations in the Finsch kimberlite diatreme and the Bellsbank fissure kimberlite are considerably greater than those in the Premier mine, though radioelement segregation could produce the required local concentrations. Some exploratory autoradiographic measurements made on two kimberlite rock samples from Premier and De Beers Mines indicated that the radioelements were apparently distributed on a submicron scale, which would be a necessary, but not sufficient, condition for uniform α-irradiation of diamonds.Diamonds from various alluvial sources showing green and brown spots arising from much heavier and more localized radiation damage are also discussed.

St. Margaret's hospital or green coat school, westminster

St. Margaret's hospital or green coat school, westminster