Cysteine-containing peptide oxidation was studied both by using an inert platinum electrode and a sacrificial electrode (copper or zinc) generating metallic ions in electrospray ionization mass spectrometry (ESI-MS). Using peptides containing one, two and three cysteines, we have compared the different chemical and electrochemical oxidation pathways of cysteine (RS(-II)H) to cystine (RS(-I)S(-I...

The properties of dry collodion membranes previously described allow the prediction that cells of these membranes will concentrate solutes under certain conditions. Three such cases have been studied experimentally. 1. A membrane containing thiosulphate and immersed in a solution of iodine concentrates iodide ion. 2. A membrane containing sodium chromate and immersed in mercury chloride concent...

Iron(III) hydrolysis in the presence of chloride ions yields akaganéite, an iron oxyhydroxide mineral with a tunnel structure stabilized by the inclusion of chloride. Yet, the interactions of this anion with the iron oxyhydroxide precursors occurring during the hydrolysis process, as well as its mechanistic role during the formation of a solid phase are debated. Using a potentiometric titration...

A mathematical model is presented for the transport and precipitation of mineral in refilling osteons. One goal of this model was to explain calcification "halos," in which the bone near the haversian canal is more highly mineralized than the more peripheral lamellae, which have been mineralizing longer. It was assumed that the precipitation rate of mineral is proportional to the difference bet...

Calcium hydroxyapatite (HAp) is the main inorganic component of natural bones. In this review, the crystal structure and fabrication methods of HAp were first introduced; then the synthesis and applications of metal-ion-doped HAp nanoparticles were mainly reviewed. HAp was usually synthesized through solid state reaction and wet chemical precipitation, of which the properties depended on the fa...

Reactions have been observed between excited ions of carbon disulfide and carbon disulfide, water, iodine and ethylene. The ions CS3\ C,S,+, C2S3\ H2OS+, CSI+, SI+, C2H : iS+ and C2H4S+ are formed in these reactions. An additional contribution to the C2S2+ ion results from reaction of CS+ with CS2 • The reaction of I2+ with CS2 leads to the ion CS2I+. Reactions of excited molecular ions have al...

Abstract A method of iodine-125 deposition on a surface microsource silver supports for brachytherapy prostate cancer was reported, which includes preparing the support by sequentially treating them with nitric acid and thiourea solutions, followed chlorination chlorinating agent to form chloride surface, substitution chlorine atoms 125 I placing containin in solution ions create layer surface....

The mechanisms of photodegradation of binary iron- and uranium-citrate and ternary iron-uranium-citrate complexes were elucidated. Citric acid degradation products were identified by HPLC and GC, and the metal precipitates were identified by XRD and EXAFS. Photodegradation of a binuclear iron-citrate complex occurred as a result of two one-electron oxidations of citric acid with the formation o...

The structure of the title compound, (C(24)H(20)P)(2)[Te(2)I(6)], is composed of discrete PPh(4) (+) cations and centrosymmetric [Te(2)I(6)](2-) anions. The tellurium(II) atom shows a sligthly distorted square-planar TeI(4) geometry and is coordinated to two bridging and two terminal iodine atoms. The planar [Te(2)I(6)](2-) ions are isolated by the cations and no inter-molecular tellurium-halog...

Numerical simulations are presented of the ion distribution functions seen by middle-altitude spacecraft in the low-latitude boundary layer (LLBL) and cusp regions when reconnection is, or has recently been, taking place at the equatorial magnetopause. From the evolution of the distribution function with time elapsed since the ®eld line was opened, both the observed energy/observation-time and ...