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151.
Jiahe Huang Xiaofeng Zhao Hongyan Zhang Ju Bai Shuhong Wang Cheng Wang Dongge Ma Yanjun Hou 《RSC advances》2019,9(17):9392
In this study, poly(9,9-dioctylfluorene-2,7-diyl) (PFO) was synthesized through the Suzuki reaction, and it was characterized. A sandwich type memory device based on PFO and PFO:ZnO, was fabricated using rotary-coating technology. I–V characteristics of the device were studied, and the effects of ZnO nanoparticle (NP) doping content on the performances of the device were discussed. The best doping content of ZnO NPs was found by processing the experimental results (4.76 wt%). Also, the stability of the device was tested, and it was found that the device remained stable after a long testing period. Furthermore, the switching mechanism of the device was discussed.In this study, poly(9,9-dioctylfluorene-2,7-diyl) (PFO) was synthesized through the Suzuki reaction, and it was characterized. 相似文献
152.
Xianheng Song Xiang Luo Jianfei Sheng Jianheng Li Zefeng Zhu Zhibo Du Hui Miao Meng Yan Mingkang Li Yong Zou 《RSC advances》2019,9(30):17391
A copper-catalyzed intramolecular cross dehydrogenative C–O coupling reaction of 2′-hydroxyl-3-arylcoumarins was developed. This protocol provided a facile and efficient strategy for the construction of natural coumestans and derivatives in moderate to high yields. This transformation exhibited good functional group compatibility and was amenable to substrates with free phenolic hydroxyl groups.A copper-catalyzed intramolecular cross dehydrogenative C–O coupling reaction of 2′-hydroxyl-3-arylcoumarins was developed. 相似文献
153.
Guoyun Fang Yao Huang Wei Yuan Yang Yang Yong Tang Weida Ju Fujian Chu Zepeng Zhao 《RSC advances》2019,9(18):9951
A novel battery thermal management system (BTMS) based on water evaporation (WE) and air-cooling (AC) for a tube–shell Li-ion battery (LIB) pack is designed. A sodium alginate (SA) film with a higher water content above 99% is fortified by adding polyethylene (PE) fibers. The air flow and PE-fiber composite sodium alginate (PECSA) film are both used to control the temperature of the battery pack. Results show that the maximum temperature of the battery pack can be controlled below 32 °C, when WE coupled with AC is used at a discharge rate of 1.8C within a discharge time of 1000 s. This method yields the highest performance of thermal management. The experimental results validate the numerical data, confirming that the design of WE combined with AC helps prevent overheating of a battery pack. This work also provides an automatic refilling system to solve the dehydration problem of the PECSA film.A novel battery thermal management system (BTMS) based on water evaporation (WE) and air-cooling (AC) for a tube–shell Li-ion battery (LIB) pack is designed. 相似文献
154.
Sanis Juliet Reghu Ravindran Sunil A Ramankutty Ajith Kumar K Gopalan Suresh N Nair Amithamol K Kavillimakkil Amitabh Bandyopadhyay Ajay Kumar S Rawat Srikanta Ghosh 《亚太热带病杂志(英文版)》2012,2(3):225-229
ObjectiveTo study the effect of ethanolic extract of leaves of the plant Jatropha curcas as a step towards developing a safe and ecofriendly therapeutic agent to combat the problems of tick and tick-borne diseases.MethodsPulverised leaves of J. curcas were subjected to soxhlet extraction using ethanol. The ethanolic extract of J. curcas at different dilutions such as, 50, 60, 70, 80, 90 and 100 mg / ml were tested against ticks using adult immersion test. The per cent adult mortality, inhibition of fecundity and hatching of laid ova were studied.ResultsThe extract caused significant blocking of hatching of the laid ova by the treated ticks.ConclusionsEclosion blocking effect of J. curcas extract is a promising property of the plant that can be utilized for controlling the population of ticks. 相似文献
155.
The dissipation and residue of myclobutanil in lychee under field conditions were studied. To determine myclobutanil residue
in samples, an analytical method with a florisil column clean-up and detected by gas chromatography-electron capture detector
(GC-ECD) was developed. Recoveries were found in the range of 83.24 %–89.00 % with relative standard deviations of 2.67 %–9.88 %.
This method was successfully applied to analyze the dissipation and residue of myclobutanil in lychee in Guangdong and Guangxi
Province, China. The half lives in lychee were from 2.2 to 3.4 days. The residues of myclobutanil in lychee flesh were all
below the limit of quantification (LOQ) value (0.01 mg/kg), and most of the residues were concentrated in the peel. The terminal
residues of myclobutanil were all bellow the maximum residue limit (MRL) value set by European Union (EU) (0.02 mg/kg). Hence
it was safe for the use of this pesticide and the results also could give a reference for MRL setting of myclobutanil in lychee
in China. 相似文献
156.
Harwood AD Bunch AR Flickinger DL You J Lydy MJ 《Archives of environmental contamination and toxicology》2012,62(3):438-444
Multiple factors can influence bioavailability, which can make predictions of toxicity in natural systems difficult. The current
study examined the potential use of solid-phase microextraction fibers as a matrix-independent approach to predict the toxicity
of permethrin to Daphnia magna across various water sources, including a laboratory reconstituted water, two natural waters, and a modified natural water.
Water source strongly affected the toxicity of permethrin as well as the concentration–response relationships. Although permethrin
concentrations in the water were predictive of toxicity to D. magna for individual water sources, there was no relationship between permethrin concentrations among water sources and mortality.
This indicated that compositional differences among water sources can greatly influence toxicity, suggesting that benchmarks
established using reconstituted water may be overly conservative for some natural waters. In addition, although permethrin
tissue residues were predictive of mortality for individual waters, the correlation among waters was not as clear. Finally,
both 48-h and equilibrium-based SPME fiber concentrations adequately predicted toxicity independent of water properties. This
demonstrated that bioavailability-based estimates provided a more accurate prediction of toxicity than water concentrations
and that SPME fibers could be used in environmental monitoring as a rapid and accurate means of predicting toxicity in natural
waters. 相似文献
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