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1.
The effect of traffic noise on sleep of young adults in their homes   总被引:1,自引:0,他引:1  
The disturbance of sleep by traffic noise is a major problem area in noise pollution. Extensive laboratory tests using multichannel electroencephalograms (EEG) have been carried out by many workers to determine the general response of people when exposed to noise during sleep. An experimental technique for obtaining results in people's homes has been developed using a simplified one-channel EEG. The responses of six people in the age range 19-24 were measured. A significant correlation was found between sleep disturbance and traffic noise when the noise is expressed in EPNdB. In the home experiments the subjects appeared to be approximately 10 dB less sensitive to noises than laboratory subjects for similar noise exposure. There also appeared to be some adaptation to the noise exposure; however, only one subject was tested for a period of 20 days and was insufficient to give definite results on adaptation.  相似文献   
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The ν3 fundamental band (CO stretch) of HDCO at 1724 cm?1 has been studied using both conventional infrared absorption and CO laser Stark spectroscopy. In addition to the excited-state (v3 = 1) rotational constants, improved constants for the ground state of HDCO have been obtained by combining previous microwave data with some infrared combination differences. The following constants were determined:
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A high performance liquid chromatography (HPLC) method for the determination of the anticoccidial and antitheilerial drug halofuginone in bovine plasma was developed. Samples were diluted with acetic acid (10%, v/v) and cleaned up on a Bond Elut C8 column. The analyte was eluted from the extraction column and chromatographed by reversed-phase HPLC using decylamine as a competing-ion reagent. Detection was by UV at 243 nm. Recovery from plasma was 75%, and within-day and between-day coefficients of variation were 5.23 and 6.35% respectively. The specificity and sensitivity of this method (limit of detection in plasma, 1 ng/mL) were sufficiently high to enable us to characterize the time course of the drug in plasma after oral administration of therapeutic doses to cattle.  相似文献   
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Phosphorescence from polyolefins was studied from the aspects of excitation and emission wavelength and lifetime. Effects of photochemical oxidation on polypropylene phosphorescence are discussed in contrast to the effects of thermal oxidation.  相似文献   
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The millimeter-wave spectrum of the normal isotope of the CO dimer, (12C16O)2, has been systematically surveyed in the regions 75-105 and 131-174 GHz, with additional measurements covering the entire 60-176 GHz range. By combining these results and using the technique of combination differences based on previously known energy levels, 14 new rotational levels have been assigned and precisely (≈0.1 MHz) located. They belong to 3 completely new states, 1 with A+ symmetry and 2 with A symmetry. The position of the lowest energy A state results in a new and lower value for the effective tunneling splitting of the CO dimer, 3.73 cm−1. The observation of dramatically different intensities for different bands supports the concept of two isomeric forms for (CO)2, the ground state having a larger intermolecular separation (≈4.4 Å) with most likely a C-bonded configuration, and the low-lying (0.88 cm−1) excited state having a smaller separation (≈4.0 Å) and an O-bonded geometry.  相似文献   
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High resolution infrared spectra of He(N)-CO2 clusters with N up to 17 have been studied in the region of the CO2 nu(3) fundamental band. The B rotational constant initially drops as expected for a normal molecule, reaching a minimum for N=5. Its subsequent rise for N=6 to 11 can be interpreted as the transition from a normal (though floppy) molecule to a quantum solvation regime. For N>13, the B value becomes approximately constant with a value about 17% larger than that measured in much larger helium nanodroplets. Quantum Monte Carlo calculations of pure rotational spectra are in excellent agreement with the measured B in this size range and complement the experimental study with detailed structural information. For a larger cluster size (N=30-50) the simulations show a clear sign of convergence towards the nanodroplet B value.  相似文献   
ConstantGround statev3 = 1 stateUnits
ν01724.267cm?1
A198 119.75198 210.4MHz
B34 910.64634 676.6MHz
C29 561.48829 331.3MHz
μa2.33022.3486D
μb0.1950.190D
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