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81.
Invasive fungus-growing ambrosia beetles are an emerging threat to forest ecosystems and fruit industries, but management
tools are lacking. Here we explored the potential of beetle symbionts–ambrosia fungi–as a source of attractants. Our focus
was the redbay ambrosia beetle, Xyleborus glabratus, and its symbiotic fungus, Raffaelea lauricola, which are devastating lauraceous hosts in the southeastern United States. We also tested three additional co-occurring beetle
species and their symbionts. Each beetle species was consistently attracted to the odors of its symbiotic fungal species,
occasionally also to symbionts of other species, but never to non-symbiotic Trichoderma. We further confirmed attraction to ethanol (positive control) in some species. Thus, ambrosia fungi produce volatiles attractive
to their vector beetles, which may have potential as novel lures for ambrosia beetle management. 相似文献
82.
83.
Bark cloth fabric has been in production in Uganda since the thirteenth century. In a move to preserve its cultural heritage, the United Nations Educational, Scientific and Cultural Organization (UNESCO) proclaimed in 2005 that Ugandan bark cloth is a “Masterpiece of the Oral and Intangible Heritage of Humanity.” Plant fibers require surface treatment before aimed at impurity reduction and for enhancement of fiber to matrix adhesion in composites. An exploratory investigation of enzymatic and plasma treatment of bark cloth is reported. The morphology of the fabric was investigated using scanning electron microscope. Thermal behavior of the fabric was studied using thermogravimetric analysis and differential scanning calorimetry. Fourier transform infrared spectroscopy and ultraviolet–visible (UV–vis) spectrophotometer were used to evaluate the surface functional groups. Enzyme-treated fabrics were cleaner and thermally stable compared to plasma and untreated fabrics. 相似文献
84.
Rajesh Mishra Richa Tiwari Miroslava Marsalkova B.K. Behera Jiri Militky 《纺织学会志》2013,104(12):1361-1368
In the present investigation, a novel technique has been developed to fabricate composite materials containing TiO2 nanoparticles, polysiloxane resin, and basalt fabric. A high-intensity ultrasonic probe was used to obtain a homogenous molecular mixture of TiO2 nanoparticles and polysiloxane resin, thus the nanoparticles were infused into the resin through sonic cavitation. The loading effect of TiO2 nanoparticles on the thermal and mechanical properties of basalt fabric reinforced polysiloxane composite materials has been investigated. Composite samples were prepared, each using two layers of basalt fabric with TiO2 nanoparticles loading from 0.5, 1, 1.5, 2, 2.5, and 3% by weight. Size distribution of nanoparticles was observed by particle size analyzer and the prepared fabric nanocomposites were characterized by scanning electron microscopy, dynamic mechanical analysis (DMA), thermo gravimetric analysis (TGA), and differential scanning calorimetry (DSC). Tensile testing was performed as per American standard for testing of materials (ASTM) standards. The dependence of dynamic mechanical parameters E′, E′′, tan (delta), T g, and heat distortion temperature (HDT) are associated with the filler content and can be controlled by the curing conditions. Tensile results show that 1.5 wt.% loading of TiO2 nanoparticles in the nanocomposites resulted in highest improvement in tensile modulus compared to the neat system. DMA studies also revealed that 1.5 wt.% doped system exhibits highest storage modulus as compared to the neat and other loading percentages. DSC and TGA studies show that T g and HDT of the composite increases with the increase in wt.% of nanofillers in the composite. Based on these results, it is clear that miscibility of nanoparticles in the resin is of prime importance with regard to performance. 相似文献
85.
The objective of the presented work is to test the possibility of using thermoelectric power to convert flue gas waste heat from a small-scale domestic pellet boiler, and to assess the influence of a thermoelectric generator on its function. A prototype of the generator, able to be connected to an existing device, was designed, constructed, and tested. The performance of the generator as well as the impact of the generator on the operation of the boiler was investigated under various operating conditions. The boiler gained auxiliary power and could become a combined heat and power unit allowing self-sufficient operation. The created unit represents an independent source of electricity with effective use of fuel. 相似文献
86.
Today’s many-core processors are manufactured in inherently unreliable technologies. Massively defective technologies used for production of many-core processors are the direct consequence of the feature size shrinkage in today’s CMOS (complementary metal-oxide-semiconductor) technology. Due to these reliability problems, fault-tolerance of many-core processors becomes one of the major challenges. To reduce the probability of failures of many-core processors various fault tolerance techniques can be applied. The most preferable and promising techniques are the ones that can be easily implemented and have minimal cost while providing high level of processor fault tolerance. One of the promising techniques for detection of faulty cores, and consequently, for performing the first step in providing many-core processor fault tolerance is mutual testing among processor cores. Mutual testing can be performed either in a random manner or according to a deterministic scheduling policy. In the paper we deal with random execution of mutual tests. Effectiveness of such testing can be evaluated through its modeling. In the paper, we have shown how Stochastic Petri Nets can be used for this purpose and have obtained some results that can be useful for developing and implementation of testing procedure in many-core processors. 相似文献
87.
Jiri Martinec Hugo Šen Karel Svoboda Jana V. Martincová David Baxter 《Applied Thermal Engineering》2010,30(8-9):1022-1028
The thermal protection of the specific experimental instrument for monitoring of combustion conditions on the grate of municipal solid waste incinerators (MSWI) represents a very important part of the assembled measuring system. The inner part of the instrument with control electronics and diverse sensors (temperature and flue gas concentration measurements) requires sufficient thermal protection against the high temperature environment of the combustion process with a surrounding temperature higher than 1200 °C. The influence of the high temperature environment is limited, but not fully eliminated, by thermal protection. The thermal protection is applied in two different ways. The standard thermal insulation with low thermal conductivity represents passive protection. The optimal thickness of the insulation itself partially defines the heat flux to the central part of the measuring system and its impacts upon increase of the inner temperature. The second type of protection, in an active mode, in addition to low conductivity, also provides heat storage. The full-scale thermal protection is designed by means of computer calculations with boundary and initial conditions or laboratory measurements within a similar environment to that on the grate of the MSWI. An additional aim of the sufficient thermal protection development is also to minimize the final size of the experimental instrument. The experimental trials have approved the functionality of the measuring instrument in high temperatures by keeping the inner temperature at the very low level. 相似文献
88.
Jaroslav Pavlik Petr Spatenka Zdenek Stryhal Vera Hrachova Adolf Kanka Jiri Cap Josef Zicha 《Materials and Manufacturing Processes》2001,16(6):863-874
This paper describes the application of chromatic monitoring of both laboratory and industrial plasmas. The light emitted from the nitrogen plasma generated in the different plasma sources was measured with an imaging spectrograph. The emission spectra were reduced to data points representing the chromatic coordinates of these spectra. The data compression makes this method attractive for monitoring plasma parameter changes. The aim of this work was to test the possibility of application of chromatic monitoring for plasma processing. 相似文献
89.
On the existence of chaos in the electronically adjustable structures of the state variable filters
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Jiri Petrzela 《International Journal of Circuit Theory and Applications》2016,44(10):1779-1797
As demonstrated in the paper, chaotic motion can appear in state variable filters, that is, common network structures dedicated for analog signal processing. In particular, two Kerwin–Huelsman–Newcomb biquadratic filtering sections are considered for theoretical, numerical and experimental analysis. Mathematical models are designed, and conditions for evolution of typical strange attractors are provided. The corresponding largest Lyapunov exponent is calculated and visualized as a function of internal system parameters and the shape of input harmonic waveform. Mutual connection between the mathematical model and the real lumped electronic circuit is discussed in detail. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
90.
Variable narrowband transmission filters with a wide rejection band for spectrometry 总被引:2,自引:0,他引:2
Variable narrowband transmission filters are useful for the development of compact spectrometers. For this purpose the filter should be directly coupled to the detector and the wavelength of the transmission peak should move in one surface direction over a length of a few millimeters. To obtain both a wide measurement spectrum and high accuracy, the ratio of extreme operating wavelengths is required to be greater than 2:1 and the width of the transmission band narrower than 10 nm. A metal-dielectric variable transmission filter, with an operating range of 400-1000 nm, is proposed. The method for obtaining variable transmission filters, with dimensions of a few millimeters, is described. 相似文献