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开胃促长补血；顶磺；氟甲氯；金诺；退热败毒；

Study of Dissolved Chlorofluorocarbons in Lake Washington

Measurements of three chlorofluorocarbons (CFCs): trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) and trichlorotrifluoroethane (CFC-113), along with methyl chloroform (CH 3CCl 3) and carbon tetrachloride (CCl 4) were made in water samples from Lake Washington, using Electron Capture-Gas Chromatography (EC-GC). The samples were collected in mid-autumn, a period when the lake’s upper layer undergoes rapid cooling. At the time of sampling, a strong vertical temperature gradient was present in the lake, with surface temperatures of ～14℃, and near bottom (50 meters) temperatures of ～8℃. The concentrations of dissolved CFC-12 and CFC-11 increased with depth, as expected from the higher solubilities of these gases at lower temperatures. Atmospheric measurements made at the sampling site at the time of the cruise, showed that CFC-11 and CFC-12 saturations in the near surface samples were 100 % and 106%, respectively. For the deepest sample (52 meters) CFC-11 and CFC-12 saturations were 102 % and 126 %. Because the surface layer of the lake responds to changes in atmospheric CFCs on a time scale of several weeks, the higher than equilibrium concentrations of CFC-12 observed at the time of sampling may reflect earlier episodes of elevated levels of atmospheric CFC-12 in this urban area. High concentrations of dissolved CFCs in runoff or industrial effluent might also lead to elevated CFC levels in the lake. The cold, deep water of Lake Washington is relatively isolated from the effects of surface gas exchange except during winter, and the supersaturations observed in the deep layer may reflect periods of elevated atmospheric CFC-12 levels from the previous winter season. These results were compared to summertime profiles of CFC-11 and CFC-12 made in 1994.

Ion-Pair Photodissociation of Trichloromonofluoromethane

fragments, F- and Cl- including two isotope species 35Cl- and 37Cl-, are observed in the photoexcitations of CFC13. The ion-pair anion efficiency spectra of 35Cl- and 37Cl- are recorded in the photon energy range of 7.75-22.00 eV. The threshold of ion-pair dissociation CFCl3-CFC12＋＋Cl- is experimentally determined to be 7.944-0.04 eV. With the references of the high-resolution photoabsorption spectra reported in the literatures, we make tentative assignments of the electron valence-to-Rydberg transitions. Furthermore, the multibody ion-pair fragmentation processes to Cl- are discussed by comparison between the calculated thermochemical thresholds and the experimental efficiency spectrum.

DOBUTAMINE MAGNETIC RESONANCE IMAGING PREDICTS CONTRACTILE RESERVE OF CHRONICALLY DYSFUNCTIONAL MYOCARDIUM: COMPARISON WITH FLUORINE-18 FLUORODEOXYGLUCOSE POSITRON EMISSION TOMOGRAPHY

This study sought to investigate whether low dose dobutamine MRI can detect residual myocardial viability in patients with chronic myocardial infarction and left ventricular dysfunction. Methods. Eleven patients with chronic myocardial infarction and left ventricular dysfunction were employed for identification of viable myocardium by cine MRI during dobutamine infusion. All patients underwent coronary angiography and left ventriculography, 18 FDG PET, MRI at rest and stress.The systolic wall thickening measured at rest and during stress was compared with the results of 18 FDG PET, respectively. Results. A significant difference of either dobutamine induced systolic wall thickening (SWth stress ) or dobutamine induced contractile reserve (ΔSWth= SWth stress - SWth rest ) was present between viable and scar regions (1 0±0 3 versus -0 3 ±0 1, P<0 01; 1 0±0 3 versus -0 2±0 2, P<0 01). Conclusions. Dobutamine induced contractile reserve can be predicted in the regions of akinesia or dyskinesia at rest when systolic wall thickening was 1 0 mm during dobutamine stimulation.

Photodissociation Dynamics of Dichlorodifluoromethane（CF2Cl2） around 235 nm using Time-Sliced Velocity Map Imaging Technology

Photodissociation dynamics of dichlorodifluoromethane (CF2Cl2) around 235 nm has been studied using the time-sliced velocity map imaging technology in combination with the resonance enhanced multi-photon ionization technology. By measuring the raw images of chlorine atoms which are formed via one-photon dissociation of CF2Cl2, the speed and angular distributions can be directly obtained. The speed distribution of excited-state chlorine atoms consists of high translation energy (ET) and low ET components, which are related to direct dissociation on 3Q0 state and predissociation on the ground state induced by internal conversion, respectively. The speed distribution of ground-state chlorine atoms also consists of high ET and low ET components which are related to predissociation between 3Q0 and 1Q1 states and predissociation on the ground state induced by internal conversion, respectively. Radical dissociation channel is confirmed, nevertheless, secondary dissociation and three-body dissociation channels are excluded.

In vivo Toxicity of Beta-cyfluthrin Insecticide against the Red Palm Weevil, Rhynchophorus ferrugineus （Olivier）

The red palm weevil （RPW） Rhynchophorusferrugineus is one of the most invasive insect pests causing massive damage on date palms over the world. Synthetic pyrethroid insecticide beta-cyfluthrin has been evaluated against developmental stages of RPW under laboratory conditions. These stages were exposed to residual film of the insecticide on transparent cups using a Potter precision laboratory spray tower. Percent mortality of males and females were recorded 0.5, 2.0 and 24 h after treatment. Furthermore, date palm offshoots were infested in mesh house, two months later, offshoots treated with 300 ppm （p.g/mL） beta-eyfluthrin using two methods dipping and injection. Bioassay test showed beta-cyfluthrin at 300 ppm caused 86,7% and 93,3% mortality against males and females after 2 h respectively with LC50 135.74 and 109.4 ppm. By increasing the concentration at 400 ppm, mortality reached 100% against males and females after 24 h, Developmental stages, eggs and larvae were more sensitive toward the insecticide, where at 120 ppm no eggs hatched after 96 h and 86.7% mortality was recorded at 200 ppm against larvae after 30 rain with LC50 93.19 ppm. In addition, dipping method of date palm offshoots in 300 ppm beta-cyfluthrin was a very convenient way to control all RPW stages compared to injection method. So, it possible to recommend this method for treating the date palm offshoots in such insecticide as one of the most important elements of integrated pest management for standardizing insecticide based quarantine protocols.