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排序方式: 共有337条查询结果,搜索用时 31 毫秒
91.
Naka H Vang le V Inomata S Ando T Kimura T Honda H Tsuchida K Sakurai H 《Journal of chemical ecology》2003,29(11):2447-2459
Three electroantennogram (EAG)-active components were detected by gas chromatography coupled to an electroantennographic detector (GC–EAD) analysis of a hexane extract of the pheromone glands of the persimmon fruit moth, Stathmopoda masinissa. These compounds were identified as (4E,6Z)-4,6-hexadecadienal (E4,Z6-16:Ald) and the corresponding acetate (E4,Z6-16: OAc) and alcohol (E4,Z6-16:OH) by mass spectral, GC retention time (RT), and microchemical test data. The characteristic base peak of the aldehyde at m/z 84 provided a crucial piece of information suggesting the possibility of a 4,6-diene structure. The (4E,6Z)-isomer elicited the strongest EAG responses among the four geometrical isomers of each synthetic 4,6-hexadecadienyl compound. In a laboratory bioassay, only E4,Z6-16:OAc elicited male moth behavioral activity significantly different from the control; the activity of the acetate was not affected by addition of the aldehyde and alcohol. A preliminary field trial confirmed that E4,Z6-16:OAc as a single component attracted male moths. The possible roles of E4,Z6-16:Ald and E4,Z6-16:OH as components of lures for field use remain to be determined. 相似文献
92.
Tomokazu Umeyama Kensuke Naka Mia D. Bravo Akiko Nakahashi Yoshiki Chujo 《Polymer Bulletin》2004,52(3-4):191-199
Summary
Cross-linked poly(vinylene-arsine)s (4) were synthesized by a free-radical terpolymerization of phenylacetylene (2), hexaphenylcyclohexaarsine (l), and p- or m-diethynylbenzene (p- or m-3) at different compositions in the presence of a catalytic amount of AIBN. The number-average molecular weights of the resulting polymers were a few thousands estimated by gel permeation chromatography (GPC) analysis. By gas chromatography (GC) analysis p-3 was found to be more reactive during the polymerization than m-3 and the resulting cross-linked polymer (p-4) showed lower solubility than that of m-4. The cross-linked poly(vinylene-arsine)s showed higher glass transition temperature in the measurement of differential scanning calorimetry (DSC) and more red-shifted emission in chloroform solution than that of the linear poly(vinylene-arsine). These properties could be tuned by varying the monomer feed ratio. 相似文献
93.
Wes MasriAuthor Vitae Hiba Halabi Author Vitae 《Journal of Systems and Software》2011,84(7):1171-1190
The use of dynamic dependence analysis spans several areas of software research including software testing, debugging, fault localization, and security. Many of the techniques devised in these areas require the execution of large test suites in order to generate profiles that capture the dependences that occurred between given types of program elements. When the aim is to capture direct and indirect dependences between finely granular elements, such as statements and variables, this process becomes highly costly due to: (1) the large number of elements, and (2) the transitive nature of the indirect dependence relationship.The focus of this paper is on computing dynamic dependences between variables, i.e., dynamic information flow analysis or DIFA. First, because the problem of tracking dependences between statements, i.e., dynamic slicing, has already been addressed by numerous researchers. Second, because DIFA is a more difficult problem given that the number of variables in a program is unbounded. We present an algorithm that, in the context of test suite execution, leverages the already computed dependences to efficiently compute subsequent dependences within the same or later test runs. To evaluate our proposed algorithm, we conducted an empirical comparative study that contrasted it, with respect to efficiency, to three other algorithms: (1) a naïve basic algorithm, (2) a memoization based algorithm that does not leverage computed dependences from previous test runs, and (3) an algorithm that uses reduced ordered binary decision diagrams (roBDDs) to maintain and manage dependences. The results indicated that our new DIFA algorithm performed considerably better in terms of both runtime and memory consumption. 相似文献
94.
Koichi Kanaya Eisaku Oho Michiaki Naka Takehiko Koyanagi Toshihide Sasaki 《Microscopy research and technique》1985,2(2):73-87
Based on the information transmission theory, topographic image signals in scanning electron microscopy are used to evaluate contrast, gradient, acutance, and Laplacian operator, the total of which represent the image sharpness of an edge line. One may consider the impulse and step functions as an input to the Gaussian system function of a low-pass filter, the impulse and step response functions possibly representing a single spot and image contrast of an edge profile, respectively. It is shown that the response function of acutance defined as the power of the gradient normalized by density is a more realistic representation of image edge sharpness. Also, edge sharpness can be greatly enhanced by utilizing the Laplacian operator through digital image processing for a disk specimen model with a rounded edge. Contrast increased by specimen tilt, and an edge effect due to side-scattered electrons, as well as the signal attenuation by specimen collection, are consistently obtained as the response function in the system. The exact measurement of spot size and edge-to-edge resolution, and image sharpness improvement, are derived by digital image processing. 相似文献
95.
Barber Sarah J.; Franklin Nancy; Naka Makiko; Yoshimura Hiroki 《Canadian Metallurgical Quarterly》2010,36(2):545
Source monitoring is made difficult when the similarity between candidate sources increases. The current work examines how individual differences in social intelligence and perspective-taking abilities serve to increase source similarity and thus negatively impact source memory. Strangers first engaged in a cooperative storytelling task. On each trial, a single word was shown to both participants, but only 1 participant was designated to add a story sentence, using this assigned word. As predicted, social intelligence negatively predicted performance in a subsequent source-monitoring task. In a 2nd study, preventing participants from being able to anticipate their partner’s next contribution to the story eliminated the effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
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98.
Three different techniques, which are tracer, drainage and weighing methods, are used to measure liquid holdup in a laboratory trickle-bed reactor operated under high pressure. The holdup measurements are compared to determine the applicability of these methods at high pressure operation. It was found that tracer and drainage techniques give comparable values for the total liquid holdup. Although several investigators recommended the weighing method over the others based on their experiments performed at atmospheric conditions, it was found that the weighing method failed to measure liquid holdup properly at high pressure operation. 相似文献
99.
Teresa Moreno Xavier Querol Jesús de la Rosa MariCruz Minguillón Yolanda González-Castanedo Wes Gibbons 《The Science of the total environment》2010,408(20):4569-722
The emission of trace metal pollutants by industry and transport takes place on a scale large enough to alter atmospheric chemistry and results in measurable differences between the urban background of inhalable particulate matter (PM) in different towns. This is particularly well demonstrated by the technogenic release into the atmosphere of V, Ni, and lanthanoid elements. We compare PM concentrations of these metals in large datasets from five industrial towns in Spain variously influenced by emissions from refinery, power station, shipping, stainless steel, ceramic tiles and brick-making. Increased La/Ce values in urban background inhalable PM, due to La-contamination from refineries and their residual products (fuel oils and petcoke), contrast with Ce-rich emissions from the ceramic related industry, and clearly demonstrate the value of this ratio as a sensitive and reliable tracer for many point source emissions. Similarly, anomalously high V/Ni values (> 4) can detect the influence of nearby high-V petcoke and fuel oil combustion, although the use of this ratio in urban background PM is limited by overlapping values in natural and anthropogenic materials. Geochemical characterisation of urban background PM is a valuable compliment to the physical monitoring of aerosols widely employed in urban areas, especially given the relevance of trace metal inhalation to urban health issues. 相似文献
100.