Titanium Nitride Coating as a Multipactor Suppressor on RF Coupler Ceramic Windows

International audienceLAL-Orsay is developing an important effort on R&D studies on RF power couplers. One of the most critical components of those devices is the ceramic RF window that allows the power flux to be injected in the coaxial line. The presence of a dielectric window on a high power RF line has a strong influence on the multipactor phenomena. To reduce this effect, the decrease the secondary emission yield (SEY)of the ceramic window is needed. Due to its low SEY coefficient, TiN coating is used for this goal. In this framework, a TiN sputtering bench has been developed in LAL. The reactive sputtering of TiN needs the optimisation of gas flow parameters and electrical one, to obtain stoechiometric deposit. XRD analysis was performed to control the film composition and stoechiometry. Measurements point out how the Nitrogen vacancy on the film can be controlled acting on the N2 flow. In addition, the coating thickness must be optimized so that the TiN coating effectively reduces the SEY coefficient but does not cause excessive heating, due to ohmic loss. For this purposes, multipactor level breakdown and resistance measurements were done for different deposit thickness

Clostridium septicum infection of hepatic metastases following alcohol injection: a case report

Clostridium septicum infections are generally associated with gastrointestinal or hematologic malignancies. We report the first case of hepatic metastases infection with Clostridium septicum that followed alcohol injection of liver lesion. Clinicians should consider this possibility in patients with underlying malignancy who present with hepatic abscess, as prompt surgical drainage and empiric antibiotics may be life saving

Titanium Nitride Coating of RF Ceramic Windows by Reactive DC Magnetron Sputtering

International audienceLAL-Orsay is developing an important effort on R&D and technology studies on RF power couplers for superconductive cavities. These are complex and high technology devices due to their basic functions: vacuum and temperature separation form the environment to the cavity. One of the most critical components of high power couplers is the ceramic RF window that allows the power flux to be injected in the coaxial line. The presence of a dielectric window on a high power RF line has in fact a strong influence on the multipactor phenomena, a resonant electron discharge that is strongly limiting for the RF components performances. The most important method to reduce the multipactor is to decrease the secondary emission yield of the ceramic window. Due to its low secondary electron emission coefficient, TiN thin film is used as a multipactor suppressor coating on RF ceramic coupler windows. In the framework of the EU program FP6 the LAL-Orsay and the LNL-Legnaro establish a collaboration to develop a coating bench that takes into account the different strong constraints on stoechiometry and film coating thickness given by coupler operating conditions. Reactive magnetron sputtering technology was chosen to obtain such deposit. A full description of a sputtering bench recently installed in LAL, and its main characteristics are given. Stoechiometric TiN films are obtained by optimization of reactive gas flow (N2), for a given bias and a given ionisation gas flow (Ar). XRD analysis was performed to control film composition. From the data obtained, lattice parameter is calculated for each deposit and film stoechiometry is determined. XPS analysis of stoechiometric film had shown the existence of oxygen and carbon mainly in the surface. However, it shows also that the ratio Ti/N in atomic percentage is equal to 1

The role of innovation and technology in sustaining the petroleum and petrochemical industry

Innovation and Technology go hand in hand within the petroleum and petrochemical industry. Oil price volatility, geopolitics, and economic uncertainty, all contribute towards the continued need to innovate and technologically advance if petroleum and petrochemical companies are to survive in this highly competitive industry. This review paper looks at identifying the importance of innovation and technology in the petroleum and petrochemical industry by referring to evidence in the public domain. Thereafter, the focus shifts towards identifying both quantifiable and non-quantifiable impacts of technology and innovation within the petroleum and petrochemical industry

Use of chromatin stability assay, mitochondrial stain JC-1, and fluorometric assessment of plasma membrane to evaluate frozen-thawed ram semen

P. 121-133Cryopreservation of semen imposes deleterious effects on spermatozoa, either killing a certain proportion of cells or causing subtle damages on sperm function in the surviving population, changes not easily revealed by conventional assays. We have tested three functional assessment techniques in frozen-thawed ram semen from six adult rams, cryopreserved following eight different protocols (four extenders, and glycerol being added at two temperatures). Semen samples were thawed and the following analyses were carried out: motility (CASA), membrane integrity (Hoescht 33258 and fluorometry), chromatin status (chromatin stability test and fluorescence-assisted cell sorting, FACS) and mitochondrial activity (JC-1 and FACS). Fluorometry outcome did not correlate with the other parameters and showed large variation, albeit discriminating among cryopreservation techniques (P<0.01). Mitochondrial activity correlated, but with low values, with total and progressive motility. However, good sperm motility and high velocity values were associated to high mitochondrial membrane potential. The chromatin stability assay was also successfully carried out, and had a good relationship with male factor (%COMP αt and SD αt parameters). In conclusion, fluorometric assessment of membrane integrity albeit rendering poor results, merits improvement, being a low-cost and handy technique, especially for work in the field. On the other hand, both assessments of chromatin stability and mitochondrial status (JC-1 staining), combined with FACS, are reliable techniques that can be used for the functional assessment of frozen-thawed ram semen.S

Application of exploratory factor analysis method in the evaluating the competitiveness of port services

This applied research has been conducted to evaluate the competitiveness of port services using exploratory factor analysis and importance- performance analysis methods. First, by studying the ports competiveness literatures, 53 indicators of competitiveness of port services has been identified, And to reduce the number of variables affecting the competitiveness of ports and the formation of a new structure for them (Based on the correlations between variables), exploratory factor analysis method was used. Based on the obtained results from 53 identified indicators, in the factor analysis, only 27 of indicator have loadings on the eight factors of Logistics Cost, Connectivity, Port facility, Port Service and Availability, Safety and security, Efficiency and Productivity, Reliability, Hinterland condition. The obtained results from confirmatory factor analysis in this study showed that, among the eight factors, factors of Logistics Cost and factors of Connectivity have greatest influence on the port competitiveness. And factors of Reliability and factors of Hinterland condition have least influence on the port competitiveness. And also the results of the importance and performance analysis showed that among of eight factors, respectively efficiency and productivity factor has the highest and Hinterland condition has the lowest the difference between the performance averages from importance average. And also the Position of each factor in the quarters of the importance and performance matrix indicates that other than the second factor (Connectivity) and fifth factor (Safety and Security) all other factors located in a quarter one. Thus it can be concluded that the services of studies port from the perspective of located factors in quarter one (logistics costs, port facilities, port services, productivity and efficiency, reliability and the Hinterland) has a low performance And needs performance improvement according to their importance

Relative efficiency analysis of container ports in Middle East using DEA

The aim of this study was to evaluate the relative efficiency of major container ports in the Middle East between the years 2011-2013. The required information was collected from scientific resources. The input and output data was collected from the statistical yearbook of the Iranian Ports and Maritime Organization and the official website of each of the foreign ports. Firstly, in this study the relative efficiency of the ports was evaluated via a basic model of the DEA-technique, namely BCC-O. Afterwards, the ports were ranked based on the achieved results. To rank ports with 100% efficiency, the Anderson-Peterson method was used. Based on the results of the output-oriented CCR model that represents the overall technical efficiency, the port of Khorafkan has the highest coefficient of efficiency and Bandar-e-Imam Khomeini was the weakest port in this respect. The average efficiency of the studied ports was 54.3% in the period under study. Finally, virtual ports were proposed as a template for inefficient ports to improve efficiency