Results 1 - 10 of 1752
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[en] The carbonyl derivatives are reduced by Cp2NbH3 and give the corresponding alcohol or hydrocarbon according to the nature (aromatic or aliphatic) of the substituents of the carbonyl group
[fr]Les derives carbonyles sont reduits par le trihydrure de niobiocene en l'alcool ou le carbure correspondant selon la nature (aromatique ou aliphatique) des substituants du groupe carbonyle
[en] Silica particles were modified with a poly(4-vinylpyridine) (P4VP) for efficient separation of oil-in-water emulsions. Using a 3-(aminopropyl) triethoxysilane (APTES)-based molecule coupled to an appropriate radical initiator, P4VP chains were built from silica surfaces under mild reaction conditions using surface-initiated supplemental activator and reducing agent atom transfer radical polymerization. P4VP-modified silica particles were successfully used as a pH-switchable barrier for oil/water separation and proved to be efficient in removing oil from an oil-in-water nanoemulsion.
[en] Six kinds of natural cosmetic raw material powder (Zedoary, Siamese rough bush, soft chalk mixtured, tuberous plant, cattle-fish bones, create) and five of herbal cosmetics (facial scrub powder, facial wash powder, tooth powder) were studied. Samples were irradiated in dry state by gamma radiation and kept to investigate microbial quality for twelve months. Minimum dose of 2.5 kilogray can reduce the exceed number of microbial loads in some samples at lest 90% or 1 log cycle from the beginning. the dose at least 7.5 kilogray can diminish the exceeded 1,000 colony/gram of contamination in all samples to the desired level. No change in number of survivors during storage were detected. No skin irritation effects were observed up to 10 kilogray and major physicochemical proper (pH and color] were not significantly changed in all samples except tooth powder
[en] Click polymerization is a powerful polymerization technique for the construction of new macromolecules with well-defined structures and multifaceted functionalities. Here, we synthesize reduction-responsive polymeric prodrug PEG-b-(PSS-g-MTX)-b-PEG containing disulfide bonds and pendant methotrexate (MTX) via two-step click polymerization followed by conjugating MTX to pendant hydroxyl. MTX content in polymeric prodrug is 13.5%. Polymeric prodrug is able to form polymeric micelles by self-assembly in aqueous solution. Polymeric micelles are spherical nanoparticles with tens of nanometers in size. Of note, polymeric micelles are reduction-responsive due to disulfide bonds in the backbone of PEG-b-(PSS-g-MTX)-b-PEG and could release pendant drugs in the presence of the reducing agents such as DL-dithiothreitol (DTT).
[en] Size-controllable copper nanomaterials were easily obtained via an improved polyol process by regulating the dosage of copper source and reducing agent. The monodisperse copper nanoparticles with strong antioxidation properties were employed as fillers to fabricate conductive ink. The copper-based ink could be screen-printed onto flexible substrates, which shows persistent stability and uniform properties without color change for a few days. After heating at 240 °C (40 min) in N2 atmosphere, a low electrical resistivity of 16.2 μΩ cm was obtained for the copper nanomaterial-based conductive pattern.
[en] As evidence of its effectiveness rapidly accumulates, the Lomi process has most recently been used to decontaminate the recirculation loops and the reactor water clean-up unit of a BWR at Monticello in the United States. An average decontamination factor of 23 was achieved in the recirculation loops. (author)
[en] Labeling of diethylenetriamine-N,N,N',N',N'-pentakis(methylenephosphonic) acid (DTPMP) with rhenium-188 using stannous chloride as a reducing agent has been investigated. Dependence of the yield of the 188Re-DTPMP complex on the concentration of the reducing agent, pH, reaction time, temperature, ascorbic acid and amount of carrier added has been studied. Under optimum conditions, the labeling yield of 188Re-DTPMP complex is 95% for the carrier-free 188Re but with the carrier-added 188Re the labeling yield is more than 97%. Furthermore, the stability of the 188Re-DTPMP complex against pH change and dilution with saline has been also studied. It is found that the addition of carrier stabilizes the 188Re-DTPMP complex against pH change and dilution. (author)
[en] An aqueous solution of a neptunium compounds is treated by a reagent, preferentially a vanadyl sulfate oxidized by cerium IV ions, to obtain neptunium V by oxidation of neptunium IV and reduction of neptunium VI. The reagent is chosen for a negligible absorption at the wavelength used for neptunium V absorption spectrophotometry for instance 981 nm
[fr]On traite la solution aqueuse de compose de neptunium par un reactif, de preference le sulfate de vanadyle partiellement oxyde par des ions cerium IV, pour obtenir du neptunium au degre d'oxydation V par oxydation de Np IV et reduction de Np VI. Le reactif est choisi de facon a ne pas presenter d'absorption significative a la longueur d'onde utilisee pour le dosage du neptunium V p. ex. a 981 nm
[en] The formation conditions, composition [Re(IV):oxime=1:4], stability in acidic solutions and analytical application of some rhenium(V) complexes with alicyclic α-dioximes (C5, C6, C7, C8) and 1,2,3-cyclohexanetrione trioxime were studied by spectrophotometricaly in hydrochloric acid medium in the presence of tin(II) chloride and other reducing agents. (author). 13 refs, 10 figs, 1 tab