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111.
Guido Velten Anja S. Rott Csar Cardona Silvia Dorn 《Journal of Stored Products Research》2007,43(4):550-557
To protect stored beans from attack by Acanthoscelides obtectus and other bruchids by non-toxic means of control, it is desirable to combine mutually compatible methods in an integrated approach. A combination of an optimal level of host–plant resistance based on the natural storage protein arcelin and a larval parasitoid has been suggested as a promising two-component strategy. While a dose–response to arcelin is evident in the bruchid Zabrotes subfasciatus, the effects of different arcelin concentrations on A. obtectus are still virtually unknown, even though they might be important for the success of the proposed integrated control system. The current investigation quantified the effect of different arcelin-based resistance levels of beans on the development of A. obtectus in a series of bioassays. Our findings show that all seven tested bean lines with markedly different levels of arcelin-based resistance against Z. subfasciatus consistently prolonged development of A. obtectus. Results provide clear evidence that arcelin acts as a growth inhibitor on first instar larvae. Furthermore, arcelin affected bruchid female fitness through its effect on body mass, which was significantly reduced on all arcelin-containing bean lines. This study demonstrates that, irrespective of its relative concentration, arcelin holds the potential to affect development of A. obtectus sufficiently to support the proposed two-component integrated pest management system. 相似文献
112.
Comparative study on volatile compounds,fatty acids,squalene and quality parameters from whole fruit,pulp and seed oils of two tunisian olive cultivars using chemometrics
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113.
A chemically enhanced biological process for lowering operative costs and solid residues of industrial recalcitrant wastewater treatment 总被引:1,自引:0,他引:1
An innovative process based on ozone-enhanced biological degradation, carried out in an aerobic granular biomass system (SBBGR - Sequencing Batch Biofilter Granular Reactor), was tested at pilot scale for tannery wastewater treatment chosen as representative of industrial recalcitrant wastewater. The results have shown that the process was able to meet the current discharge limits when the biologically treated wastewater was recirculated through an adjacent reactor where a specific ozone dose of 120 mg O3/Linfluent was used. The benefits produced by using ozone were appreciable even visually since the final effluent of the process looked like tap water. In comparison with the conventional treatment, the proposed process was able to reduce the sludge production by 25-30 times and to save 60% of operating costs.Molecular in situ detection methods were employed in combination with the traditional measurements (oxygen uptake rate, total protein content, extracellular polymeric substances and hydrophobicity) to evaluate microbial activity and composition, and the structure of the biomass. A stable presence of active bacterial populations was observed in the biomass with the simultaneous occurrence of distinctive functional microbial groups involved in carbon, nitrogen and sulphate removal under different reaction environments established within the large microbial aggregates. The structure and activity of the biomass were not affected by the use of ozone. 相似文献
114.
Highly bright and photostable cyanine dye-doped silica nanoparticles for optical imaging: Photophysical characterization and cell tests 总被引:1,自引:0,他引:1
Ivana Miletto Alessandra Gilardino Pollyanna Zamburlin Simona Dalmazzo Davide Lovisolo Giuseppe Caputo Guido Viscardi Gianmario Martra 《Dyes and Pigments》2010,84(1):121-127
Spherical silica nanoparticles containing fluorescent trimethine indocyanine dyes (λabs = 547 nm, λem = 570 nm) were prepared using a water-in-oil microemulsion method. The nanoparticles were of 50 nm diameter and were almost monodispersed in aqueous solution at pH 5.5. Entrapment of dye molecules in the silica matrix stabilised photoemission over several hours of continuous irradiation. The photoemission intensity of the indocyanine was increased 13-fold over that recorded in solution. As each nanoparticle contained 110 dye molecules, the photoemission brightness of each particle was enhanced by three orders of magnitude. The fluorescent nanoparticles have been tested as imaging tools in in vitro tests. As an example of non-macrophagic cells, a highly differentiated neuronal cell line (GT1-7) was used and the results showed that the prepared nanoparticles can be incorporated into these cells with no apparent toxicity for up to three days. 相似文献
115.
Im Zuge des massenhaften Einsatzes von Probebelastungen im 19. und zu Beginn des 20. Jahrhunderts zeigte sich die Notwendigkeit, deren Planung, Durchführung und Auswertung durch allgemeine Richtlinien und Normen zu stützen. Im Beitrag wird das Ringen um erste zaghafte Festlegungen beschrieben, die im Laufe der Jahre immer konkreter zu einer verwendbaren Handlungsgrundlage ausgearbeitet wurden. Unter Kritikern blieb jedoch immer die Frage über die Sicherheit und vor allem die Aussagekraft von Belastungsversuchen auf der Grundlage der verwendeten Bewertungskriterien offen. Mit der Weiterentwicklung der Berechnungsverfahren auch durch den Einsatz von Computertechnik wurden Probebelastungen von Neubauten ab den 1970‐er Jahren entbehrlich. Für auffällig gewordene bestehende Tragwerke stellt die Probebelastung jedoch auch heute noch eine — und manchmal die einzige — Methode zum Nachweis einer ausreichenden Tragfähigkeit dar. Die hierfür angewendete moderne Belastungs‐ und Messtechnologie bietet jedoch im Unterschied zur traditionellen Vorgehensweise ein hohes Maß an Sicherheit und Informationsgewinn. Historical Development and current practise of load tests in situ — Part 2: Development of standards and current practise. Because of the large demand and use of load testing in the 19th and at the beginning of the 20th century, there was the necessity to standardise the planning, execution and analysis in general guidelines and codes. This article describes the struggling and first tentative specification, which were more and more specified to an useful basis in the following years. The used criterions for the assessment have often been a reason for critics on the value and the safety of loading tests. The further development of calculation methods especially the computer technology made the load testing of new structures superfluous in the 1970s. But for existing structures loading tests are today often a — and sometimes the only — method to proof a sufficient load bearing capacity. The today used modern loading‐ and measuring technology provides, in contrast to the traditional method, a high degree of safety and structural information. 相似文献
116.
Carlo Beatrice Chiara Guido Pierpaolo Napolitano Silvana Di Iorio Nicola Del Giacomo 《Fuel》2011,90(5):2039-2044
Results of a research project aimed at studying the capability to develop a method (economic and simple) for on-board biodiesel blending detection are described. The method is based on the direct measurement of the Indicated Mean Effective Pressure (IMEP).The study was carried out on a 2.0L four-cylinder “torque-controlled” Euro 5 diesel engine for passenger car (PC) application. This engine, equipped with instrumented glow plug for combustion closed-loop control, represents the state of the art of the diesel engine control technology.Two biodiesels were chosen for the experiments: a rapeseed methyl-ester (RME) and an aged RME, while the conventional diesel fuel was an European (EU) certification diesel fuel.Results indicate generally a good response in blending detection of the method. However, in order to attain an acceptable accuracy, a pre-calibration appears necessary. 相似文献
117.
Previous research shows that asymmetric information triggers a decrease of lot sizes compared to the supply chain optimum.
Thus, the setup costs per period are suboptimally high. To analyse, whether setup cost reduction can mitigate this effect,
we extend the standard framework of lotsizing decisions under asymmetric information by allowing investments in setup cost
reduction. We find that asymmetric information tends to lead to an overinvestment in setup cost reduction. The overall effect
of setup cost reduction on supply chain performance is therefore ambiguous. We show that these results hold for a wide variety
of investment functions. 相似文献
118.
119.
120.
Abstract An empirical electrical equivalent circuit for dielectric thin films, based on experimental data, is developed. Current responses to voltage-steps and to voltage-ramps are calculated and compared with experimental data. The simulation allows us to separate current contributions of different physical processes while the experiment only reveals the sum of the currents. 相似文献