Abstracl-LBNL is using pressurized bladders in its high field snperconducting magnet program. Magnet RD3j a 14 Trace track dipole; has been assembled and pre-stressed using such a system. The bladder, placed between the coil pack and the iron yoke, can provide 70 MPa of pressure while compressing the coil pack and tensioning a 40 mm thick structural Aluminum shell. Interference keys replace the bladder's functionality as they are deflated and removed leaving the shell in 140 MPa of tension. During cool down, stress in the shell increases to 250 MPa as a result of the difrerencc in thermal expansion between the Aluminum shell and the inner iron yoke. A number of strain gauges mounted onto the shell were used to monitor its strain during assembly, cool·down and testing. This technique ensures that the final and ma'"(imum stress in the shell is reached before the magnet is ever energized.The use of a structural shell and pressurized bladders has simplified magnet assembly considerably. In this paper we describe the bladder system and its usc in the assembly of a 14T Nb3Sn magnet.

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The subtherapeutic use of antimicrobial drugs has played an important role in animal husbandry by the control of disease, the improvement of growth and efficiency of feed conversion. Livestock producers, industry, veterinary, and regulatory personnel share responsibility to ensure freedom from drug metabolites, residues, and other chemicals to which livestock and poultry may be exposed. The predominant concerns are for the potential adverse effects on human health. Data demonstrate that the feeding of subtherapeutic antimicrobials to livestock and poultry increases the prevalence of R+ enteric organisms. Some of these organisms may be pathogenic for humans.

A b s W t -A superconducting magnet usssmbly Bar Been built for rm ECR (Electron Cyclotron Resonarm$ Ion sowce at the 88~inch cyclohoti at LBL'. Three 34-cm ID solenoids provide axhl plasma cotijintw" and U sexfupole ussembly in the solenoid bore provides radial stabill@. Two large solenoid8 are spaced SO em. npwi with a smaller opposing solenoid bedween. The sexlupole ussembly is 92 cm long with winding inner diameter of 20 cm. and outer diameter of 27.2 em. Tfis design goat is fo achieve afield on axis of 4 T und 3 T a t the mirrors with 0.4 T behvees and a sexfapole field of 2.0 T at IS-cm diumeter iti the confinement volume. Emfr solenoid uses rectrsngrrlar conductor wtth mpper/'SC ratio of 4; flie three coils are wet-wound on a one-piece aluminlrm bobbin with aluminum bnndti!g for rudiui suppord. The sexapole uses rectangular conductor with copper/SC ratio of 3. EacR of the 6 eoik is wet-wound with filled epoxy ori a metal pole; the ends of the pole are ahminum and the central 34-cm h lron to augment the sextupokfldd. The a& coils me assembled on a 2O-cni4lD stainless steel hrbe with a I.4-cm thick 30.0.cm OD aluminum tribe over the assembly for striictural support. Thin metal bludders are exparrded adtnut!ially behveen each coil axially ab the ends to pre-load the assembly, The sexhrpob assembbflts inside lire solenoid bobtin, wlikb provMes support for the magnetic forces. The magnet exceeds design requirements with ni inim um training.