Se.C.R.E.T.S.: A stability experiment on the role of segregated copper in Nb/sub 3/Sn cable-in-conduit conductors

In Se.C.R.E.T.S. (Segregated Copper Ratio Transient Stability), the stability performance under transverse field transient is compared for two Nb/sub 3/Sn cable-in-conduit conductors which differ only because of the different distribution of the stabilizing copper, either included in the Nb/sub 3/Sn strand cross section or segregated as bundled copper wires. If the segregated copper is found to be effective for stability purposes, the copper fraction in the Nb/sub 3/Sn strands can be substantially reduced, with dramatic cost advantage for the high field fusion magnets. The experiment is assembled in the SULTAN facility at CRPP, with 11 T background field and superimposed transverse pulsed field to generate the transient disturbance. The layout of the conductor, the winding sample and the assembly procedure are described. The instrumentation and the test program are planned to provide results to be easily extrapolated to the ITER conductors

Characterization tests of the Nb₃Sn calbe-in-conduit conductors for Se.C.R.E.T.S.

Two Nb3Sn cable-in-conduit conductors have been procured for Se.C.R.E.T.S. (Segregated Copper Ratio Experiment on Transient Stability). The two conductors are identical in the fractional cross sections. The only difference is the location of the copper stabilizer, included either as segregated copper wires or as copper shell in the superconducting strands. A number of characterization tests, on individual strands and cabled conductors, have been carried out to establish a solid data base for the assessment of the results in the main experiment

Scientific bases of calculation, design and making of superconducting transposed wires with stabilization by copper and aluminium

Superconducting transposed wires are considered in the paper aiming at the distribution investigation of transport and induced currents, losses of electromagnetic energy in multiwired superconducting wires. The development of analytical methods of the characteristic calculation and the formulation of design principles are also the aim of the paper as well as the elaboration of optimized constructions and the determination of technological possibilities of their making. As a result the calculation theory of the energy loss and current distribution in multiwired superconducting cores, carrying transport current and exposed to varying magnetic field, has been developed. The methodology of the multiwired construction optimization has been suggested. Recommendations for the choice of the constructive parameter collection of multiwired cores as the function of the multifactor influence of operation conditions have been formulated. New constructions and technologies of their making have been developed and investigated, pilot-industrial production has been organized. The complex of the test equipment for current to 80 kA has been created. Calculation methods and new constructions have been introduced into operation in Russian Academy of Sciences institutes and electrotechnical enterprises. Technological recommendations have been introduced into operation on enterprises of the cable subbranch. The output of new high-effective constructions of wires has been organized, unique electrotechnical devices have been created on their baseAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

Lectin from <em>Canavalia brasiliensis</em> Seeds (ConBr) Is a Valuable Biotechnological Tool to Stimulate the Growth of <em>Rhizobium tropici</em> <em>in Vitro</em>

To study the interactions between a <em>Rhizobium tropici</em> strain and lectins isolated from the seeds of <em>Canavalia ensiformis</em> (ConA) and <em>Canavalia brasiliensis</em> (ConBr), a lectin fluorescence assay was performed. In addition, an experiment was designed to evaluate the effect of the two lectins on bacterial growth. Both lectins were found to bind to <em>R. tropici</em> cells, but the interactions were inhibited by D-mannose. Interestingly, only ConBr stimulated bacterial growth in proportion to the concentrations used (15.6–500 µg/mL), and the bacterial growth stimulation was inhibited by D-mannose as well. Structure/Function analyses by bioinformatics were carried out to evaluate the volume and carbohydrate recognition domain (CRD) configuration of ConA and ConBr. The difference of spatial arrangement and volume of CRD may indicate the variation between biological activities of both lectins. The results suggest that ConBr could be a promising tool for studies focusing on the interactions between rhizobia and host plants