Reactive magnetron cosputtering of hard and conductive ternary nitride thin films: Ti-Zr-N and Ti-Ta-N Properties of reactively radio frequency-magnetron sputtered ( Zr , Sn ) TiO 4 dielectric films Copper nitride ͑Cu 3 N͒ thin films were deposited on glass substrates by reactive radio-frequency magnetron sputtering of a pure copper target in a nitrogen/argon atmosphere. The deposition rate of the films gradually decreased with increasing nitrogen flow rate. The color of the deposited films was a reddish dark brown. The Cu 3 N films obtained by this method were strongly textured with crystal direction ͓100͔. The grain size of the polycrystalline films ranged from 16 to 26 nm. The Hall effect of the copper nitride ͑Cu 3 N͒ thin films was investigated. The optical energy gap of the films was obtained from the Hall coefficient and found to vary with the nitrogen content. The surface morphology was studied by scanning electron microscopy and atomic force microscopy. The copper nitride thin films are unstable and decompose into nitrogen and copper upon heat treatment when annealed in vacuum with argon protected at 200°C for 1 h.

The aim of this study was to evaluate the modified rifampin oligonucleotide (RIFO) macroarray method to detect mutations in the hot-spot region of the rpoB gene, associated with rifampin (RIF) resistance in Mycobacterium tuberculosis. The study sample included 123 strains of M. tuberculosis isolated in the Beijing, China, area in 2002-2005, including 73 RIF-resistant and 40 pansusceptible strains. The genotypic assay successfully identified 91.8% of the RIF-resistant strains, whereas no mutations were found in RIF-susceptible strains. The most frequently detected rpoB mutations were in the codons 516, 526, and 531, together accounting for 74% of RIF-resistant strains. Spoligotyping subdivided all strains into 11 unique profiles and 3 profiles shared by 3, 4, and 103 strains, respectively. The 113 strains belonged to the Beijing family genotypes, defined by the specific spoligotype signature (absence of signals 1-34) and deletion of the RD105 region. The rpoB S531L (TCG-->TTG) mutation was found in 57.4% of the RIF-resistant strains of the Beijing genotype. A mutation in the rpoB hot-spot region was found in 51 of the 55 (92.7%) multidrug-resistant strains (i.e., resistant to at least RIF and isoniazid), thus demonstrating the added utility of the modified RIFO method to predict multidrug resistance. The RIFO method is relatively simple to perform and allows straightforward interpretation of results; consequently, it can be used in clinical diagnostic laboratories as a fast complement to phenotypic methods.

The Hall effect of copper nitride (Cu 3 N) thin films was investigated in our work. Cu 3 N films were deposited on glass substrates by radio-frequency (RF) magnetron sputtering at different temperatures using pure copper as the sputtering target. The Hall coefficients of the films are demonstrated to be dependent on the deposition gas flow rate and the measuring temperature. Both the Hall coefficient and resistance of the Cu 3 N films increase with the nitrogen gas flow rate at room temperature, while the Hall mobility and the carrier density of the films decrease. As the temperature changed from 100 K to 300 K, the Hall coefficient and the resistivity of the films decreased, while the carrier density increased and Hall mobility shows no great change. The energy band gap of the Cu 3 N films deduced from the curve of the common logarithm of the Hall coefficient against 1/T is 1.17 -1.31 eV.The interest in copper nitride thin film had been growing in recent years due to its potential applications as write-once optical recording media [1] and precursor material for microscopic copper lines by maskless laser writing [2,3]. Copper nitride (Cu 3 N) is one of the important covalent metal nitride compounds and has been scarcely studied. The decomposition of this material into elements due to low thermal stability [4] suggests its possible use in metallization reactions [5], which could be of significant importance in the electronics industry, for instance, the feasibility of using this film to generate metal lines by maskless laser writing was explored recently [2]. Although Cu 3 N film could have many technological applications, few papers are available concerning its physical properties and the correlation between the chemical bonding and the physical properties. As a semiconductor material, more studies are needed. The Hall effect is a useful way to characterize the semiconductor materials, by which the carrier density and mobility can be measured. In device technology, Hall effect devices are widely used in the fields of measuring, automatization, information technology, etc.Various methods had been employed to obtain copper nitride films, such as RF-sputtering [6, 7], RF-plasma chemical reactor [8,9] and reactive pulsed laser deposition [10]. In these papers some physical and chemical properties of the copper nitride thin films have been studied. Herein, we firstly investigated the Hall effect of the Cu 3 N films prepared by reactive RF-sputtering deposition. ExperimentCopper nitride films were prepared by a reactive radio-frequency (RF) magnetron sputtering system. The sputtering target is made of oxygen-free copper with a purity of 99.9%. Commercial glass sheets as substrates were ultrasonically cleaned in acetone. The working gas was a mixture of 99.999% pure Ar and

The radical tandem bicyclization provides a novel approach for the preparation of complex polycyclic compounds in synthetic chemistry. Herein, we first described a tandem radical bicyclization reaction of CN-containing 1,6-enynes...

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