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121.
The far-infrared torsional spectrum of ClONO2 (chlorine nitrate) was reexamined at 0.06-cm?1 apodized resolution. The torsional spectrum consists of a single, regularly spaced series of Q branches at 122.56 ? 2.422 v′ + 0.0296 v2 cm?1. Chlorine nitrate is planar with torsional potential constants V2 = 1900 ± 100 cm?1 and V4 = 90 ± 50 cm?1. The torsional partition function is calculated at room and stratospheric temperatures.  相似文献   
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123.
Stearic acid spin label substituted with deuterium in all positions and15N in the paramagnetic group has been synthesized and was found to display a 5.5 fold gain in sensitivity in the EPR spectrum and a 60% decrease in linewidth compared to the unmodified analog.  相似文献   
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Polymer solutions in the vicinity of the theta-point are known to undergo shear-induced turbidity or phase separation. The present study shows that a similar phenomenon also occurs for certain wormlike micellar solutions. Wormlike micelles are the self-assembled counterparts of polymers and are characterized by their ability to reversibly break and recombine. In the system of interest, the micelles are formed by the cationic surfactant erucyl bis(hydroxyethyl)methylammonium chloride (EHAC), in conjunction with a salt such as sodium chloride (NaCl) or sodium salicylate (NaSal). Micellar samples that become turbid under shear show evidence of critical concentration fluctuations and may contain predominantly branched micelles. The shear-induced turbidity in these samples correlates with the appearance of flow-dichroism in rheooptic experiments and with an increase in low-q scattering in small-angle light scattering under flow (flow-SALS) experiments. The characteristic "butterfly" pattern, with enhanced scattering in the flow direction and a dark streak perpendicular to the flow direction, is typically observed in flow-SALS. The results suggest that the turbidity is due to a shear-induced growth of concentration fluctuations, which in turn manifests as large anisotropic domains, typically oriented along the vorticity axis.  相似文献   
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Utilizing a general entry we had developed for the synthesis of C-aryl glycosides, we have prepared the juglone derivatives 18-20 as well as the juglone precursor 13. Because 19 had been previously converted in two steps by Suzuki into galtamycinone (1), its preparation constitutes a total synthesis of 1.  相似文献   
129.
We have continued our kinetics investigation of the iodosobenzoate (IBA) catalysis of the hydrolysis of p-nitrophenyl diphenyl phosphate (PNDP), in microemulsion media composed of hexadecane in water stabilized by cetyltrimethylammonium bromide and 1-butanol over a range of water mass fractions. We have examined two iodosobenzoic acid derivatives (5-nitro-2-iodosobenzoic acid and 5-octyloxy-2-iodosobenzoic acid) as catalysts. In addition, we have determined by31P FT-NMR techniques that the major product of the hydrolysis of PNDP, both in IBA catalyzed and in uncatalyzed media, is diphenylphosphate.  相似文献   
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