The rate of atmospheric vanadium is constantly increasing due to fossil fuel combustion. This environmental pollution favours vanadium exposure in particular to its vanadate form, causing occupational bronchial asthma and bronchitis. Based on the well admitted bronchodilator properties of the pituitary adenylate cyclase-activating polypeptide (PACAP), we investigated the ability of this neurope...

An autonomous sensor for monitoring phosphate levels in aqueous samples has been developed. The sensor is based on the molybdenum yellow method for detection of phosphate, which involves the formation of a yellow-coloured compound when a phosphate-containing sample is mixed with an acidic reagent containing ammonium molybdate and ammonium metavanadate. The reaction is carried out in a microflui...

Chromium is a trace metal of importance in human physiology and, in addition, as 51-chromate, has been extensively used as a label in the study of blood cell pool sizes and intravascular kinetics. The transport characteristics of 51-chromate were investigated in normal human leukocytes. Chromate uptake is unidirectional over a 1 hr incubation with extracellular chromate concentrations up to 200...

The oxidative dehydrogenation (ODH) of propane was investigated on vanadia dispersed on alumina containing a nominal polymolybdate monolayer (4.8 Mo/nm2). Dehydrogenation rates and selectivities on these catalysts were compared with those on vanadia domains dispersed on alumina. At a given vanadia surface density, ODH reaction rates per gram of catalyst were about 1.5–2 times greater on MoOx -c...

High purity ammonium metavanadate (NH4VO3) is the most vital chemical to produce V2O5, VO2, VN alloy, VFe alloy and VOSO4, which have some prospective applications for high strength steel, smart window, infrared detector imaging, large scale energy storage system. NH4VO3 usually produced by spontaneous crystallization from aqueous solution due its sharp dependence of solubility on temperature. ...

본 연구에서는 소듐바나데이트 수용액에 염화암모늄을 첨가하여 암모늄메타바나데이트를 침전시킬 때, 암모늄메타바나데이트의 용해도와 암모늄이온의 분해율이 침전반응에 미치는 영향을 알아보았다. 침전온도와 수용액 pH가 증가함에 따라 암모늄 이온의 증가하였으며 45 ℃에서 pH 9.3일 때 분해율은 81% 이상으로 8일 때와 비교하였을 약 4배 정도 증가하였다. 그러므로 침전 반응에 큰 두 인자를 고려하여 침전반응을 수행한 결과, 침전온도가 침전속도가 증가하였으나 35 ℃ 이상에서는 침전온도의 영향이 크지 않았다. 침전반응 속도론적 고찰을 통하여 얻은 침전반응의 활성화 에너지는 42.3 kJ/mol이었다. 이와 같은 연구를 용해도를 고려하였을 침전온도는 낮을수록 바나듐 회수율에 유리하였다. 또한 분해를 수용액의 ...