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1.
A novel method to eliminate T3 from gross sera/plasma based on prior treatment with 8-anilino-1-naphthalene sulphonic acid has been standardized. This method is rapid with a minimum loss of protein and uses only small quantities of charcoal. The treated sera have been tested for acceptance in the RIA system for routine assays.  相似文献   
2.
This is the report of neutrino and astroparticle physics working group at WHEPP-7. Discussions and work on CP violation in long baseline neutrino experiments, ultra high energy neutrinos, supernova neutrinos and water Cerenkov detectors are discussed.  相似文献   
3.
Some new members of a ruthenocuprate(2212) series have been synthesized by Mn substitution for Ru in Gd1.4Ce0.6Sr2RuCu2O10. Characterization by x-ray diffraction (XRD) phase analysis has been carried out. Changes in structural features on substitution, including a significant change in lattice parameter for a very low substitution level, have been observed. Four-probe resistivity studies indicate the coexistence of superconductivity and magnetism for the pristine compound and a semiconductor-like upturn in resistivity and the absence of superconductivity even for very low levels of Mn substitution. AC susceptibility measurements show a progressive suppression of the magnetic transition temperature as well as a smearing of the magnetic transition as a function of Mn substitution. Possible reasons for the absence of superconductivity have been discussed.  相似文献   
4.
Transition Metal Chemistry - The synthesis and structural characterization of new metal(II) chelates (M = CoII, NiII, CuII and ZnII) of neutral conjugated bidentate β-diketone ligands, having...  相似文献   
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A sensitive thyroxin /T4/ radioimmunoassay procedure with a short incubation time /10 min/ similar to a conventional stat test in clinical chemistry is described. The assay parameters such as concentration of antisera and125I-T4, and incubation temperature that affect the kinetics of antigen-antibody reaction have been studied. Within- and between-assay variations were less than 7% CV. Analysis of 45 serum samples by the proposed method and by a conventional assay gave similar results /Y=1.05X–0.187; r=0.990/.  相似文献   
7.
Treatment of [Cp*CrCl(C6F5)]2 with BnMgCl (Bn = benzyl) in Et2O/THF affords [Cp*Cr(C6F5)(Bn)(THF)] (1) which has been isolated in 72% yield. This compound whose magnetic moment is equal to of 4.037 μB has been characterized by NMR and single crystal X-ray analysis. Compound 1 alone does not polymerize ethylene when dissolved in toluene. However, addition of excess AlEt3 to a solution of 1 in toluene leads to a catalytically active system which readily oligomerizes ethylene under standard conditions. Oligomerization experiments carried out with [1] = 10−3 M and [AlEt3] = 9 × 10−2 M for 15 min lead to the production of ethylene oligomers with an activity of 280 kg mol Cr−1 h−1. The experimental molecular weight distribution observed at intermediate times during the reaction is satisfactorily accounted for by the Poisson distribution formula, which is indicative of a living polymerization system. These observations are in agreement with a catalytic cycle in which the growing alkyl chain is transferred from chromium to aluminum via a bimetallic complex in which the chromium and aluminum centers are bridged by an alkyl group and the growing polymer chain.  相似文献   
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We have studied the feasibility of producing57Co (271.3 d) via the55Mn(, 2n)57Co reaction (55Mn–100%). The thick target yield of57Co in the 28 to 18 MeV energy region was measured as 3.87 Ci/Ah. However, the proximity and overlap of the excitation functions for (, n), (, 2n) and (, 3n) reactions on55Mn are such that the production of pure57Co in high yields free of58Co (70.8 d) and56Co (78.8 d) has not been feasible. We have also studied a new method for ancillary production of57Co via the reactions58Ni(, p)57Co and during the course of producing62Zn by60Ni(, 2n)62Zn reaction. In this case the yield of57Co of reasonable purity has been up to 1 Ci/Ah.  相似文献   
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