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Sotiris Stasinos Marios Kostakis Nikolaos Thomaidis Ioannis Zabetakis 《Water, air, and soil pollution》2014,225(10):1-14
Tropospheric ozone (O3) has long been documented to cause an injury to plants, but a plants’ protectant, widely applicable in agronomical practice, does not exist. We evaluated the potential antiozonate efficacy of the antitranspirant di-1-p-menthene (Vapor Gard) compared with ethylenediurea (EDU) on Bel-W3 tobacco plants. Plants were treated either with water, or by EDU (10, 100, and 500 mg dm?3), or by vapor (1, 5, 10, and 50 ml dm?3) and were exposed either to O3-enriched (90 ppb) or O3-free air, for 12 days and 8 h day?1. EDU when applied at 10 mg dm?3 did not protect the plants against O3, but when applied at 100 and 500 mg dm?3 offered a significant protection to the plants. Vapor, when applied at 1 ml dm?3 did not protect the plants against O3, neither by terms of foliar visible injury nor by terms of aboveground biomass. In addition, when applied at 10 and 50 ml dm?3 caused phytotoxicity to all the plants, which it was expressed as necrotic spots on the leaves’ surface, misshaping of the leaves, or short plants' height. It is obvious that vapor does not protect Bel-W3 tobacco plants against O3. The antiozonate role of di-1-p-menthene is species-specific and probably occurs only under short-term exposures. 相似文献
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A simple, rapid, and low-cost gas chromatographic multiresidue method has been developed for the analysis of pesticide residues in raw and processed olives. This has been validated for 19 insecticides and triazine herbicides, covering a wide range of polarities. The method uses low-temperature precipitation to remove lipids and gives good cleanup for gas chromatography analysis with nitrogen phosphorus and electron capture detection. Recoveries are between 71 and 99%, with relative standard deviation values of 5-15%. 相似文献
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Stavros Sotiropoulos Ioannis K. Kalavrouziotis Sotiris Varnavas Christos Paschalidis Panagiotis H. Koukoulakis 《Communications in Soil Science and Plant Analysis》2018,49(9):1009-1021
A pot experiment with spinach (Spinacia oleraceae L. Fam.: Chenopodiaceae) was conducted aiming to investigate the effect of the addition of sewage sludge (SS) on soil substrate, the growth of spinach, and the plant interactions of CaxCd and ZnxCd. There were six substrates obtained by mixing soil and sludge in different proportions by volume (20:1, 10:1, 6.7:1, 5.0:1, 4.0:1, 3.3:1) and a control (only soil). The highest biomass was achieved in treatments 20:1 and 10:1. There was not a linear increase due to toxicity when SS was added in higher proportions. Sludge improved soil fertility by increasing organic matter and total N. Furthermore, in all plant parts of spinach, the Ca and Zn contents were synergistically interrelated with the Cd content, facilitating Cd uptake. The use of sewage sludge as soil amendment is not applicable on agricultural land due to the accumulation of Cd in plant. 相似文献
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The retention performance of aroma molecules from different chemical classes (e.g., alcohols, esters, aldehydes, and terpenes) by silica particles made by hydrolysis of tetraethyl orthosilicate is investigated. Since particle morphology, porosity, and pore size distribution can be controlled by the sol-gel preparation method, the influence of the nanoconfinement in the microporous matrix on aroma retention is studied as well as the effect of the initial aroma load of the particles. As the porosity is decreased, aroma molecules are entrapped more efficiently in the silica particles. The retention performance decreased from alcohols > aldehydes >/= esters > terpenes as with polar organic matrices. Open sol-gel-made silica particles show an increased retention with increasing aroma load, while denser silica matrices show a maximum retention with increasing load. 相似文献
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Masmanidis SC Karabalin RB De Vlaminck I Borghs G Freeman MR Roukes ML 《Science (New York, N.Y.)》2007,317(5839):780-783
Efficient actuation is crucial to obtaining optimal performance from nanoelectromechanical systems (NEMS). We employed epitaxial piezoelectric semiconductors to obtain efficient and fully integrated NEMS actuation, which is based on exploitation of the interaction between piezoelectric strain and built-in charge depletion. The underlying actuation mechanism in these depletion-mediated NEMS becomes important only for devices with dimensions approaching semiconductor depletion lengths. The induced actuation forces are controlled electrically, and resonant excitation approaching single-electron efficiency is demonstrated. The fundamental electromechanical coupling itself can be programmed by heterostructure band engineering, externally controllable charge depletion, and crystallographic orientation. These attributes are combined to realize a prototype, mechanically based, exclusive-or logic element. 相似文献
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Marine benthic macrophytes were examined as possible nitrogen (N) sources for agriculture in Greece in terms of N mineralization and available standing stocks. Net N mineralization patterns were determined over a 30‐week incubation period under aerobic conditions. Ulva sp., Cystoseira barbata C. Agardh, and Posidonia oceanica (L.) Delile storm‐cast material (SC) and harvested leaves (L) were incorporated into acidic, slightly acidic after liming, and alkaline soils and incubated at 35°C. From the initial stage until the 12th week of incubation, ammonification was higher than nitrification in most cases. The decreasing order of mineralized N originating from macrophytes was: Ulva sp. > P. oceanica (SC) > C. barbata > P. oceanica (L). Rates of net N mineralization of the macrophytes were the highest in the alkaline soil, whereas the lowest values were recorded in the strongly acidic soil. Application of Ca into the acidic soil revealed a considerable increase of N mineralization. Immobilization and ammonification were observed after incorporation of Ulva sp. into the acidic soil. As Ulva sp. proved to be the only potential alternative N source for arable crops, its standing stocks in two geographically different Greek lagoons, the Vassova Lagoon (N Greece) and Papas Lagoon (S Greece) were estimated. It was estimated that 2 ha of Ulva could supply adequate N to cultivate approximately 1 ha cotton. Posidonia and Cystoseira did not show potential as an alternative N source for agriculture and especially in plant nutrition. 相似文献
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