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In this work, we investigated insecticidal and repellent activities of the essential oils extracted from Ajania nitida and Ajania nematoloba against Tribolium castaneum and Lasioderma serricorne adults. The components of essential oils were analyzed by GC-MS. The main components of A. nitida oil were camphor (20.76%), thujone (18.64%), eucalyptol (13.42%), borneol (8.32%) and those of A. nematoloba oil were β-pinene (34.72%), eucalyptol (24.97%) and verbenol (20.39%). The results showed that the two essential oils possessed insecticidal and repellent activities against two species of insects. A. nitida oil possessed contact and fumigant toxicity against T. castaneum (LD

This paper proposes a new individual load forecasting method based on data mining technologies. First, the hierarchical cluster analysis is performed to analyze the historical daily load. Next, the results of hierarchical clustering, the week type and weather factors are used to establish a decision tree. Then, the SVM model is established on history days which are similar with the forecast date. Finally, the forecasted load is obtained through the SVM forecasting model. Case studies using real load data show that the proposed new method can improve the accuracy of individual load forecasting.

The present study focuses on the experimental and numerical investigation of heat transfer performance downstream of the cooling holes on a flat plate with zero streamwise pressure gradient. The experiment was conducted in a low speed wind tunnel. The holes are circular in either straight or curved shape with an angle of 90°. In the experiments, both local and transverse averaged cooling effectiveness and heat transfer coefficient in the surface are studied for single and multiple holes in a row over a range of blowing ratio from 0.5 to 1.22 for single hole and 0.32–1.18 for multiple holes. Surface temperatures downstream of the injection were measured by means of thermal liquid crystals (TLC) and its associated camera system. Numerical simulation were perform for single hole at blowing ratios 0.51 and 1.04 by using Detached Eddy Simulation (DES) method based on S–A one equation turbulence model. In comparison with the straight hole, the curved one shows better overall performance expressed by net heat flux reduction (NHFR) based on both the experimental and numerical results, such as a better transverse spreading, higher cooling effectiveness and an increased local heat transfer coefficient are concluded for the curved hole.

The chemical constituents of the essential oil extracted from Artemisia anethoides and the bioactivities of essential oil against Tribolium castaneum and Lasioderma serricorne were investigated. The main components of the essential oil were 1,8-cineole (36.54%), 2-isopropyl-5-methyl-3-cyclohexen-1-one (10.40%), terpinen-4-ol (8.58%), 2-isopropyltoluene (6.20) and pinocarveol (5.08%). The essential oil of A. anethoides possessed contact and fumigant toxicities against T. castaneum adults (LD

Two essential oil samples were obtained from the pericarp of Zanthoxylum bungeanum with the methods of hydrodistillation (HD) and supercritical fluid CO

Measurement of wind speed is an essential part of overhead transmission line monitoring. To overcome the drawbacks of the existing anemometer, such as the requirement on field power, the sensitivity to electromagnetic interference, and the unavailability of real-time measurement, a novel anemometer is developed on the basis of the fiber Bragg grating (FBG) sensing technique. In the anemometer, a beam with uniform strength was used to measure the force generated by the wind; two naked FBGs were symmetrically glued on the upper and lower surfaces of the beam to solve the problem of cross-sensitivity between strain and temperature of FBG sensing. Furthermore, the temperature effect on the zero output was investigated by putting the FBG anemometer into a temperature-controlled cabinet, and the experimental results indicated that the temperature effect on the zero output of the wind speed was less than ±5 pm (-10° C to 50 °C). The results from the wind tunnel experiment indicated that the measurement error of the anemometer was less than ±0.5 m/s.

The chemical constituents of the essential oils extracted from Artemisia giraldii and Artemisia rubripes were analyzed by GC-MS. The bioactivities of two essential oils against Tribolium castaneum and Lasioderma serricorne were investigated. The main constituents in A. giraldii essential oil were 1,8-cineole (40.72%), camphor (22.50%), terpinen-4-ol (12.41%) and α-terpineol (4.14%). β-Farnesene (12.23%), 1,8-cineole (11.09%), β-caryophyllene (10.68%), germacrene D (10.01%), camphor (7.01%) were principal constituents in A. rubripes essential oil. The essential oil of A. giraldii possessed contact and fumigant toxicities (LD50=23.72 μg/adult and LC50=16.78 mg/l air, respectively) against T. castaneum adults. In addition, the essential oil of A. giraldii possessed contact and fumigant toxicities (LD50=8.88 μg/adult and LD50=5.41 mg/l air, respectively) against L. serricorne adults. The essential oil of A. rubripes showed contact and fumigant toxicities (LD50=16.18 μg/adult and LD50=25.10 mg/l air, respectively) against L. serricorne adults, and the very low contact and fumigant toxicities against T. castaneum. The results indicated that the essential oil of A. giraldii had the potential to be developed as insecticide for control of T. castaneum and L. serricorne.

Amomum maximum Roxb. is a perennial herb distributed in South China and Southeast Asia. The objective of this work was to analyze the chemical constituents and assess insecticidal and repellent activities of the essential oil from Amomum maximum fruits against Tribolium castaneum (Herbst) and Liposcelis bostrychophila (Badonnel). The essential oil was obtained by hydrodistillation and analyzed by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. The main components of the essential oil were identified to be β-pinene (23.39%), β-caryophyllene (16.43%), α-pinene (7.55%), sylvestrene (6.61%) and ç-cadinene (4.19%). It was found that the essential oil of A. maximum fruits possessed contact and fumigant toxicities against T. castaneum adults (LD50 = 29.57 μg/adult and LC(50) = 23.09 mg/L air, respectively) and showed contact toxicity against L. bostrychophila (LD(50) = 67.46 μg/cm(2)). Repellency of the crude oil was also evaluated. After 2 h treatment, the essential oil possessed 100% repellency at 78.63 nL/cm(2) against T. castaneum and 84% repellency at 63.17 nL/cm(2) against L. bostrychophila. The results indicated that the essential oil of A. maximum fruits had the potential to be developed as a natural insecticide and repellent for control of T. castaneum and L. bostrychophila.

The chemical composition of the essential oil of Etlingera yunnanensis rhizomes and its contact and repellent activities against Tribolium castaneum (Herbst) and Liposcelis bostrychophila (Badonnel) were investigated. The essential oil obtained from E. yunnanensis rhizomes with hydrodistillation was performed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. The main components of the essential oil were identified to be estragole (65.2%), β-caryophyllene (6.4%), 1,8-cineole (6.4%), limonene (5.2%), and α-pinene (2.4%). It was found that the essential oil of E. yunnanensis rhizomes possessed contact toxicity against T. castaneum and L. bostrychophila (LD50 = 23.33 μg/adult and LD50 = 47.38 μg/cm2, respectively). Estragole, 1,8-cineole, and limonene exhibited stronger contact toxicity (LD50 values of 20.41, 18.86, and 13.40 μg/adult, respectively) than β-caryophyllene (LD50 = 41.72 μg/adult) against T. castaneum adults. Estragole possessed stronger contact toxicity (LD50 = 30.22 µg/cm2) than β-caryophyllene, 1,8-cineole, and limonene (LD50 values of 74.11, 321.20, and 239.62 μg/adult, respectively) against L. bostrychophila adults. Repellency of the crude oil was also evaluated. The essential oil and constituents possessed strong repellent activity against T. castaneum adults. The four individual constituents showed weaker repellent activity than the essential oil against L. bostrychophila adults. The results indicated that the essential oil of E. yunnanensis rhizomes and the individual constituents had the potential to be developed as a natural insecticide and repellent for the control of T. castaneum and L. bostrychophila.

The objective of this paper is to investigate the influence of a hole curvature on the flow structure and characteristics downstream of JICF (jet in cross-Flow) by means of smoke visualization and particle image velocimetry (PIV). The experiment was performed in a low speed wind tunnel with Reynolds numbers of about 480 and 1000, based on the hole diameter and main flow speed. Two geometries were tested: a circular hole with 90° curvature and a circular straight hole for comparison, under blowing ratios 0.5 and 1.0. The measurements were done in the symmetric plane and four cross-sections. The results show that the curved hole could decrease the mixing behavior of jet flow with the main flow as the hole leading edge also increases the chance of transportingthecoolant to the wall surface and the transverse coverage. The curved hole shows a high potential to increase the cooling effectiveness once it is applied to the turbine blades.