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1.
The gas-phase reaction products of the OH radical with 2-ethoxyethyl acetate (EEA, CH3C(O)OCH2CH2OCH2CH3) have been investigated. 1,2-Ethanediol acetate formate (EAF, CH3C(O)OCH2CH2OC(O)H) and ethyl formate (EF, HC(O)OCH2CH3) were identified as the two main products. A third product, ethylene glycol diacetate (EGD, CH3C(O)OCH2CH2OC(O)CH3), was also observed. EAF, EF, and EGD formation yields were determined to be 0.37 ± 0.03 and 0.328 ± 0.018 and 0.040 ± 0.005, respectively. Proposed reaction mechanisms are discussed and compared with these data. © 1996 John Wiley & Sons, Inc.  相似文献   
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Matched-field replica models based on an inaccurate knowledge of geoacoustic parameters such as bottom attenuation, shear, and interfacial sound-speed discontinuities, can predict an incorrect number of propagating modes for a shallow-water channel. The resulting degradation in the matched-field ambiguity surface can be substantially reduced by obtaining optimal replica models via modal-sum-limit optimization or bottom-property inversion. The use of these techniques for multi-tone (70, 95, 145, and 195 Hz) source-tow data recorded near San Diego during the first Shallow-Water Evaluation Cell Experiment (SWellEX-1) significantly increased matched-field correlation levels and improved source localization relative to results obtained with a previous nonoptimized model. The predicted number of propagating modes was also reduced substantially. The inversion for bottom properties (attenuation, interfacial sound-speed discontinuities, no shear) provided sediment attenuation estimates which agree well with Hamilton's models and were an order-of-magnitude greater than that used in the nonoptimized model, which accounts for the reduction in the number of modes. A simulated modal decomposition using the inverted optimal replica model verifies the number of modes predicted by the modal-sum-limit optimization.  相似文献   
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In this note, we consider a question of Móri regarding estimating the deviation of the kth terms of two discrete probability distributions in terms of the supremum distance between their generating functions over the interval [0,1]. An optimal bound for distributions on finite support is obtained. Properties of Chebyshev polynomials are employed.  相似文献   
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The relative rate technique has been used to measure the hydroxyl radical (OH) reaction rate constant of ethyl 3-ethoxypropionate (EEP, CH3CH2(SINGLE BOND)O(SINGLE BOND)CH2CH2C(O)O(SINGLE BOND)CH2CH3). EEP reacts with OH with a bimolecular rate constant of (22.9±7.4)×10−12 cm3 molecule−1s−1 at 297±3 K and 1 atmosphere total pressure. In order to more clearly define EEP's atmospheric reaction mechanism, an investigation into the OH+EEP reaction products was also conducted. The OH+EEP reaction products and yields observed were: ethyl glyoxate (EG, 25±1% HC((DOUBLE BOND)O)C((DOUBLE BOND)O)(SINGLE BOND)O(SINGLE BOND)CH2CH3), ethyl (2-formyl) acetate (EFA, 4.86±0.2%, HC((DOUBLE BOND)O)(SINGLE BOND)CH2(SINGLE BOND)C((DOUBLE BOND)O)(SINGLE BOND)O(SINGLE BOND)CH2CH3), ethyl (3-formyloxy) propionate (EFP, 30±1%, HC((DOUBLE BOND)O)(SINGLE BOND)O(SINGLE BOND)CH2CH2(SINGLE BOND)C((DOUBLE BOND)O)(SINGLE BOND)O(SINGLE BOND)CH2CH3), ethyl formate (EF, 37±1%, HC((DOUBLE BOND)O)O(SINGLE BOND)CH2CH3), and acetaldehyde (4.9±0.2%, HC((DOUBLE BOND)O)CH3). Neither the EEP's OH rate constant nor the OH/EEP reaction products have been previously reported. The products' formation pathways are discussed in light of current understanding of oxygenated hydrocarbon atmospheric chemistry. © 1997 John Wiley & Sons, Inc.  相似文献   
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The relative rate technique has been used to measure the hydroxyl radical (OH) reaction rate constant of +2-butanol (2BU, CH3CH2CH(OH)CH3) and 2-pentanol (2PE, CH3CH2CH2CH(OH)CH3). 2BU and 2PE react with OH yielding bimolecular rate constants of (8.1±2.0)×10−12 cm3molecule−1s−1 and (11.9±3.0)×10−12 cm3molecule−1s−1, respectively, at 297±3 K and 1 atmosphere total pressure. Both 2BU and 2PE OH rate constants reported here are in agreement with previously reported values [1–4]. In order to more clearly define these alcohols' atmospheric reaction mechanisms, an investigation into the OH+alcohol reaction products was also conducted. The OH+2BU reaction products and yields observed were: methyl ethyl ketone (MEK, (60±2)%, CH3CH2C((DOUBLEBOND)O)CH3) and acetaldehyde ((29±4)% HC((DOUBLEBOND)O)CH3). The OH+2PE reaction products and yields observed were: 2-pentanone (2PO, (41±4)%, CH3C((DOUBLEBOND)O)CH2CH2CH3), propionaldehyde ((14±2)% HC((DOUBLEBOND)O)CH2CH3), and acetaldehyde ((40±4)%, HC((DOUBLEBOND)O)CH3). The alcohols' reaction mechanisms are discussed in light of current understanding of oxygenated hydrocarbon atmospheric chemistry. Labeled (18O) 2BU/OH reactions were conducted to investigate 2BU's atmospheric transformation mechanism details. The findings reported here can be related to other structurally similar alcohols and may impact regulatory tools such as ground level ozone-forming potential calculations (incremental reactivity) [5]. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet 30: 745–752, 1998  相似文献   
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