From iodine-plutonium-xenon isotope systematics, we re-evaluate time constraints on the early evolution of the Earth-atmosphere system and, by inference, on the Moon-forming event. Two extinct radioactivites (I, T1/2 = 15.6 Ma, and Pu, T1/2 = 80 Ma) have produced radiogenic Xe and fissiogenic Xe, respectively, within the Earth, which related isotope fingerprints are seen in the compositions of ...

In order to prepare antibacterial and radio-opaque dental resin, a methacrylate monomer named 2-Dimethyl-2-dodecyl-1-methacryloxyethyl ammonium iodine (DDMAI) with both antibacterial and radio-opaque activities was added into a 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropyl)-phenyl]propane (Bis-GMA)/methyl methacrylate (MMA) dental resin system. Degree of conversion (DC), flexural strength (FS) a...

A convenient m ethod is presented for estimating isotope effects in reactions which yield waterto The water-t is separated by freez e!=h~yjng, and k*/k is calculated froJ? .t!J.e extent of the reaction and the ratio of the radioactIvIty of t he water-t to that of the lnItlal reactant. Application of the method to the oxidation of aJdoses-1-t at 25°C with iodine in a lkaline solution gives value...

Silver doped zeolite (AgX) has attracted significant attention as a good adsorbent of organic iodine (CH3I) in the gas phase. Heat treatment waste, which is composed iodine-sorbed AgX, may be necessary for disposal, would removed from AgX at high temperature. Therefore, sorption and desorption behaviors CH3I on X (13X) were investigated. Herein, labeled by 125I tracer was synthesized via isotop...

introduction: iodine deficiency disorders (idd) are the most common epidemiological problems in the world, including our country. in order to prevent idd and its consequences, iodized table salt is being used in our country since 1989. at present, this program is 18 years old. the surveillance of idd may be implemented to assess the prevalence of idd, identify high risk areas for intervention a...

A convenient method is presented for est imating isotope effects in reactions which yield water-J. T h e water-2 is separated by freeze-drying, and k*/k is calculated from the extent of t he reaction and the rat io of the radioactivi ty of the water-Z to t h a t of the initial reac tant . Application of the method to the oxidation of aldoses-l-£ a t 25 °C with iodine in alkaline solution gives ...

Introduction Increasing numbers of patients are receiving treatment with the tranquillizing drugs, and patients referred to hospital with suspected thyrotoxicosis are often taking such drugs. It is important to know what effects these drugs have on tests of thyroid function if diagnostic confusion is to be avoided. Diazepam is a commonly prescribed centrallyacting tranquillizer. Published work ...

Introduction Increasing numbers of patients are receiving treatment with the tranquillizing drugs, and patients referred to hospital with suspected thyrotoxicosis are often taking such drugs. It is important to know what effects these drugs have on tests of thyroid function if diagnostic confusion is to be avoided. Diazepam is a commonly prescribed centrallyacting tranquillizer. Published work ...