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81.
Solid-phase microextraction (SPME) and gas chromatography coupled with electroantennographic detection (GC-EAD) were used to identify volatile compounds from shoots of riverbank grape (Vitis riparia) that attract the female grape berry moth (GBM, Paralobesia viteana). Consistent EAD activity was obtained for 11 chemicals: (Z)-3-hexen-1-yl acetate, (E)-linalool oxide, (Z)-linalool oxide, nonanal, linalool, (E)-4,8-dimethyl-1,3,7-nonatriene, methyl salicylate, decanal, beta-caryophyllene, germacrene-D, and alpha-farnesene. In flight-tunnel tests that involved female GBM and rubber septa loaded with subsets of these 11 compounds, we found that both the 11-component blend and a seven-component blend, composed of (E)-linalool oxide, (Z)-linalool oxide, nonanal, (E)-4,8-dimethyl-1,3,7-nonatriene, decanal, beta-caryophyllene and germacrene-D, elicited equivalent levels of upwind flight as freshly cut grape shoots. The removal of any of the seven compounds from the seven-component blend resulted in a significant decrease in female upwind flight responses. In a field trial with these two synthetic blends, traps equipped with either blend captured more female GBM compared to traps baited with hexane only (control), although the number of females caught was generally low. There were no differences in the number of males captured among treatments. Although in flight-tunnel trials, moths readily flew upwind to both grape shoots and rubber septa loaded with the best lures, they landed on shoots but not on rubber septa. Coupled with relatively low field catches, this suggests that additional host finding cues need to be identified to improve trap efficacy.  相似文献   
82.
The effects of particle size of starting materials and amount of a BaTiO3 additive on the shrinkage behavior and elemental diffusion in Ni-based internal electrodes have been investigated in order to control the shrinkage of the internal electrode in multilayer ceramic capacitors (MLCCs). Two kinds of Ni and BaTiO3 powders were used with different particle sizes. Volume shrinkage over the range of 700–1300 °C at 150 °C intervals and linear shrinkage during sintering were measured for starting materials and composites in a reducing atmosphere. The interfaces of Ni/BaTiO3 composites with 90:10 and 70:30 volume ratios, respectively, were investigated using TEM. Composites with bimodal Ni powder show less shrinkage than those with monomodal Ni powder, showing less shrinkage in monolith Ni of bimodal particle size. The shrinkage behavior is changed during sintering with increasing amounts of BaTiO3 additives in both Ni-based composites. The particle size of the BaTiO3 additive affects the shrinkage behavior of composites, without the additional amount affecting the final shrinkage. A reaction layer of about 300 nm wide is observed at the interface between the Ni and BaTiO3 powders in composites, in which elemental Ni diffuses into the BaTiO3 without counterdiffusion.  相似文献   
83.
For the purpose of balancing charge carriers’ transport, we designed and synthesized two new compounds that are composed of both electron- and hole-transporting structural moieties: electron-transporting moieties are diaryl-1,3,4-oxadizole (Oxa) groups and hole transport moieties carbazole (Cz), or triphenylamine (TPA) moieties. The compounds formed amorphous glassy films when vacuum deposited and their glass transition temperature (Tg) was close to or higher than 150 °C. Their electronic structures (the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), and Eg values) and hole and electron mobilities in the compounds were studied. A couple of compounds bearing oxadiazole moieties revealed the electron mobility greater than 1.0 × 10−4 cm2/(V s) at the electric field of 7.5 × 105 V/cm. The single layer light-emitting electroluminescence (EL) devices show that the external quantum efficiencies of the devices fabricated with those compounds having balanced carrier mobilities are much higher than those of the compounds composed of predominantly hole- or electron-transporting moieties.  相似文献   
84.
Evidence suggests that augmented expression of a certain gene can influence the efficacy of targeted and conventional chemotherapies. Here, we tested whether the high expression of enhancer of the rudimentary homolog (ERH), which serves as a prognostic factor in some cancers, can influence the efficacy of anthocyanins isolated from fruits of Vitis coignetiae Pulliat, Meoru in Korea (AIMs) on human gastric cancer cells. The anticancer efficacy of AIMs was augmented in ERH-transfected MKN28 cells (E-MKN28 cells). Molecularly, ERH augmented AIM-induced caspase-dependent apoptosis by activating caspase-3 and -9. The ERH-augmented apoptotic effect was related to mitochondrial depolarization and inhibition of antiapoptotic proteins, XIAP, and Bcl-2. In addition, reactive oxygen species (ROS) generation was augmented in AIMs-treated E-MKN28 cells compared to AIMs-treated naïve MKN28 cells. In conclusion, ERH augmented AIM-induced caspase-dependent mitochondrial-related apoptosis in MKN28 cells. A decrease in expression of Bcl-2 and subsequent excessive ROS generation would be the mechanism for ERH-augmented mitochondrial-related apoptosis in AIMs-treated MKN28 cells. A decrease in expression of XIAP would be another mechanism for ERH-augmented caspase-dependent apoptosis in AIMs-treated MKN28 cells.  相似文献   
85.
This study presents a simple and robust algorithm for the optimal design of the system with coupled complex transport phenomena: the transport phenomena comprise fluid flow, heat and mass transfer. The (1+1)-Evolution Strategy method is adopted as the optimization method. In order to analyze the transport phenomena in the complex geometry generated during the optimization procedure, thefinite volume method with a boundary fitted curvilinear coordinate system is used. To confirm the validity of the present method, the optimal design for the inner shape of the simplified two-dimensionalSubmerged Entry Nozzle in the continuous slab caster is conducted. It is shown that the resulting design of the nozzle is consistent with the purpose and constraints of the design.  相似文献   
86.
李家明  查大俊 《化学试剂》2000,22(6):372-372
4[2(甲基2吡啶氨基)乙氧基]苯甲醛(1)是合成治疗糖尿病新药罗格列酮(Rosiglitazone)的关键中间体,罗格列酮已由SmithKlineBeecham公司开发上市[1]。文献报道[2~4]的制备是以2氯吡啶为起始原料与2甲氨基乙醇缩合后,在钠氢作用下与4氟苯甲醛反应制得,收率为302%。由于使用危险昂贵的试剂钠氢,工业化生产有一定难度。本文在参考文献[2~4]合成方法的基础上,以2氯吡啶为原料按文献[2]的路线制备1,其中2(甲基2吡啶氨基)乙醇(3)的合成中,加大了2甲氨基乙醇的用量,反应结束后减压回收2甲氨基乙醇,以降低成本,收率由…  相似文献   
87.
本文阐述了构建安全体系结构的意义,以及安全体系结构所包括的主要内容.重点以企业网为例介绍了应当如何根据自身实际,以安全体系为指导,构建其安全防护体系.  相似文献   
88.
In this paper, we describe a system for wandering in a realistic environment over the Internet. The environment is captured by the concentric mosaic, compressed via the reference block coder (RBC), and accessed and delivered over the Internet through the virtual media (Vmedia) access protocol. One of the key contributions of the paper is the proposal of the RBC concentric mosaic coder. The RBC coder not only compresses the huge dataset of the concentric mosaic very efficiently, but also produces a well-organized bitstream that can be accessed just-in-time (JIT). To reconstruct a virtual view, only a portion of the RBC bitstream needs to be accessed and decoded. This greatly reduces the memory and computation requirement of the viewer compared with first decoding the entire concentric mosaic data set and then rendering from the decoded data. Our second contribution is the employment of the Vmedia protocol to deliver the compressed concentric mosaic bitstream just-in-time over the Internet. Only the bitstream segments corresponding to the current view are streamed over the Internet. The delivered bitstream segments are managed by a local Vmedia cache, so that frequently used bitstream segments do not need to be streamed over the Internet repeatedly, and a RBC bitstream larger than the memory capacity can be easily handled. Combining RBC and Vmedia, a concentric mosaic interactive browser is developed through which the user can freely wander in a realistic environment, e.g., rotate around, walk forward/backward, and sidestep, even under a tight bandwidth.  相似文献   
89.
超灵敏检漏的实时校准   总被引:1,自引:2,他引:1  
超灵敏检漏的实时校准是国际上尚未解决且未标准化的一个难题,本文利用自建的微流量参考漏率系统对商用检漏仪和超灵敏检漏系统进行了实时校准的实验研究,在10-14Pa.m3/s~10-10Pa.m3/s宽范围漏率内实现了对检漏仪器的实时校准。  相似文献   
90.
A more competitive business environment requires that a variety of value management process (VMP) options be continuously introduced into the construction industry. Project stakeholders and managers are highly concerned about value maximization through implementation of one or more beneficial VMP options. The objective of this study is to identify the most leveraging project characteristic factors (PCFs) in need of VMP implementation. Furthermore, the levels of importance of each PCF in association with the optional VMPs are quantified to effectively assess the applicability of VMP implementation using the fuzzy-based analytic hierarchy process method. Four real-case validation tests provide robust research findings. The proposed project assessment tool is useful in evaluating individual projects in terms of whether the subject project is leveraged or has much to be improved by implementing the optional VMPs. The results of this study can facilitate a rigorous evaluation of a project and eventually help the decision-making process in selecting the most beneficial VMP options to maximize the optimum project value.  相似文献   
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