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51.
A.S. Carroll T.F. Kycia K.K. Li D.N. Michael P.M. Mockett D.C. Rahm R. Rubinstein 《Physics letters. [Part B]》1973,45(5):531-534
Measurements have been carried out of total cross sections of positive kaons on hydrogen and deuterium to a statistical precision of better than ± 0.1 mb for most points in the range of laboratory momentum from 410 to 1065 MeV/c in intervals of approximately 50 MeV/c. A very broad elastic structure in the I = 0 state is inferred. 相似文献
52.
C. Kourkoumelis L.K. Resvanis G. Voulgaris T.A. Filippas E. Fokitis A.M. Cnops J.H. Cobb S. Iwata R.B. Palmer D.C. Rahm P. Rehak S.D. Smith I. Stumer C.W. Fabjan T. Fields D. Lissauer I. Mannelli P. Mouzourakis A.J. Lankford 《Physics letters. [Part B]》1979,83(2):257-260
The inclusive production of π0 at large values of pT in pp collisions at the ISR has been studied. In this experiment the two photons are resolved and separately measured for pT values of up to 6 GeV/c, giving confidence that the desired signal has been separated from various backgrounds. 相似文献
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Schwartz BD Moore CJ Rahm F Hayes PY Kitching W De Voss JJ 《Journal of the American Chemical Society》2008,130(44):14853-14860
The volatile components of the mandibular gland secretion generated by the Giant Ichneumon parasitoid wasp Megarhyssa nortoni nortoni Cresson are mainly spiroacetals and methyl ketones, and all have an odd number of carbon atoms. A biosynthetic scheme rationalizing the formation of these diverse components is presented. This scheme is based on the results of incorporation studies using (2)H-labeled precursors and [(18)O]dioxygen. The key steps are postulated to be decarboxylation of beta-ketoacid equivalents, beta-oxidation (chain shortening), and monooxygenase-mediated hydroxylation leading to a putative ketodiol that cyclizes to spiroacetals. The generality of the role of monooxygenases in spiroacetal formation in insects is considered, and overall, a cohesive, internally consistent theory of spiroacetal generation by insects is presented, against which future hypotheses will have to be compared. 相似文献
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Cholinesterase-based dipstick assay for the detection of organophosphate and carbamate pesticides 总被引:2,自引:0,他引:2
A cholinesterase (ChE)-based dipstick-type assay for the class-specific detection of organophosphate (OP) and carbamate (CM) pesticides was developed. The principle of the assay is based on inhibition of the activity of a ChE by these two families of pesticides, which is dependent on the concentration of pesticides. The proposed assay system is composed of a test strip with an acetylcholinesterase (AChE)-coated membrane and an enzyme substrate solution. The assay protocol involves incubation of the enzyme-coated strip in the pesticide-containing sample solution followed by incubation of the sample-treated strip in a chromogenic enzyme substrate solution. The color intensity is estimated by the naked eye or a reflectometer. Of the membranes tested as the enzyme support, Hybond N+ was the most suitable. Among the compounds tested as the enzyme substrate, indophenyl acetate was the best. The detectable concentration range of the dipstick assay for the OP and CM pesticides was 10−6-102 and 10−6-100 μg mL−1, respectively. The sensitivity of the dipstick assay to the oxidized form of parathion (paraoxon) was higher than to parathion. The strip showed a large matrix effect with pesticide-spiked lettuce samples, whereas it showed a small matrix effect with pesticide-spiked rice samples. 相似文献
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Hyunsook Jung Hae Wan Lee Eun Ah Jeong 《Phosphorus, sulfur, and silicon and the related elements》2016,191(8):1137-1141
Thermal degradation of sulfur mustard (2,2′-dichlorodiethyl sulfide, HD) in the presence of metal oxide adsorbents was investigated by thermal desorption in conjunction with gas chromatography–mass spectrometry (GC-MS). Zr(OH)4, Al2O3, Al2CoO4, MgO, CeO2, and V2O5 were used as metal oxide adsorbents. Neat HD was spiked onto the metal oxides packed in glass tubes, which were kept at room temperature and then heated at moderately elevated temperatures of 100°C by a thermal desorption system. The products of thermal degradation were directly transferred and analyzed by GC-MS. 1,4-Dithiane and 1,4-oxathiane were characterized as the major products of the thermal degradation of HD in the presence of Zr(OH)4, Al2O3, Al2CoO4, and CeO2 adsorbents. No effective degradation was observed with MgO and V2O5. Of particular note is Zr(OH)4, which extremely enhanced the thermal degradation of HD. 相似文献
60.
We present a novel blood filter unit that is designed to separate blood plasma from whole blood by simple magnetic actuation. A non-diluted blood sample is dropped into the filter unit and magnetic attraction is applied to squeeze out only blood plasma while blood particles are filtered by membranes stacked in the filter unit. The new filter device yields good filtering performance with nearly perfect filtering efficiency (~99.999%), high plasma recovery (~30%), low blood consumption (<50 μl), and fast operation (~1 min). Because it is simple to operate and is attachable to any kind of pre-made biochip, it has commercial potential in various lab-on-a-chip applications for blood tests. 相似文献