A decision-oriented model to evaluate the effect of land use and agricultural management on herbicide contamination in stream water

Modelling stream water pollution by herbicides in agricultural areas is a critical issue since numerous and incompletely known processes are involved. A decision-oriented model, SACADEAU-Transf, which represents water and pesticide transfer in medium-sized catchments (10–50 km²) is presented. This model aims at evaluating the effect of land use, agricultural practice and landscape on the contamination of stream water in rural catchments. The processes are represented in an easily understandable way with a moderate amount of information, producing semi-quantitative and spatialized outputs. Modelling focuses on the first few months after herbicide application when high levels of contamination are generally observed, by considering transfer through the catchment area via surface and subsurface flow. The surface flow, based on a tree plot network representation of the catchment, is controlled by soil-surface properties and saturated conditions. The subsurface flow based on Topmodel concepts is controlled by the topography. Herbicide transfer is coupled to water transfer by taking into account the main characteristics of the chemicals. The model simulates the daily water and herbicide outflow at the outlets of the farmers' fields as well as from the catchment. Preliminary results on maize herbicide transfer are presented for an agricultural catchment with an area of 17 km² located in north-western France. The relevance of SACADEAU-Transf model is discussed in view of the qualities required for the decision-oriented models developed for improving agro-environmental management.     

Photocatalytic degradation of imidazolinone fungicide in TiO2-coated optical fiber reactor

The photocatalytic degradation of the fungicide fenamidone is studied in a TiO₂-coated optical fiber photoreactor. Fenamidone is slowly transformed with a kinetic order of 1 and a degradation rate of 0.02 h⁻¹. Intermediate products were isolated and identified by means of solid phase extraction (SPE) coupled to liquid chromatography-mass spectrometry techniques (LC-MS). A proposed degradation pathway of fenamidone is presented, involving mainly hydroxylation and oxidation reactions. Carboxylic acids and sulfate ions resulting from the same reaction in a powder reactor were also identified.     

Effects of smoking bans on passive smoking exposure at work and at home. The European Community respiratory health survey

This longitudinal study investigated whether smoking bans influence passive smoking at work and/or at home in the same subjects. Passive smoking at work and/or at home was investigated in random population samples (European Community Respiratory Health Survey) in 1990‐1995, with follow‐up interviews in 1998‐2003 and 2010‐2014. National smoking bans were classified as partial (restricted to public workplaces) or global (extended to private workplaces). Multivariable analysis was accomplished by three‐level logistic regression models, where level‐1, level‐2, and level‐3 units were, respectively, questionnaire responses, subjects, and centers. Passive smoking at work was reported by 31.9% in 1990‐1995, 17.5% in 1998‐2003, and 2.5% in 2010‐2014. Concurrently, passive smoking at home decreased from 28.9% to 18.2% and 8.8%. When controlling for sex, age, education, smoking status, and ECHRS wave, the odds of passive smoking at work was markedly reduced after global smoking bans (OR = 0.45, 95% CI 0.25‐0.81), particularly among non‐smokers, while the protective effect of global smoking bans on passive smoking at home was only detected in non‐smokers. Smoking bans both in public and private workplaces were effective in reducing passive smoking at work in Europe. However, given the inefficacy of smoking bans in current smokers’ dwellings, better strategies are needed to avoid smoking indoors.     

Low-temperature photoluminescence study of exciton recombination in bulk GaAsBi

The exciton recombination processes in a series of elastically strained GaAsBi epilayers are investigated by means of time-integrated and time-resolved photoluminescence at T = 10 K. The bismuth content in the samples was adjusted from 1.16% to 3.83%, as confirmed by high-resolution X-ray diffraction (HR-XRD). The results are well interpreted by carrier trapping and recombination mechanisms involving the Bi-related localized levels. Clear distinction between the localized and delocalized regime was observed in the spectral and temporal photoluminescence emission.     

Laser synthesized TiO2-based nanoparticles and their efficiency in the photocatalytic degradation of linear carboxylic acids

Abstract

Titanium dioxide nanoparticles were synthesized by laser pyrolysis, their surface and electronic properties were modified by gold and/or nitrogen. These materials were characterized by different techniques like X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR). Time resolved conductivity (TRMC) was used to study the charge separation of electron/hole pairs. Altogether (XPS, EPR, TRMC), the physicochemical characterizations are well correlated with chemical photoactivity of the different samples. Their photocatalytic activity was evaluated for the degradation of linear carboxylic acids (C2-C3) under UV and visible illumination. The decomposition rate of acids was measured, it shows that the modification with gold increases the photoactivity while the presence of nitrogen slows down the process. Such observations are in good agreement with evolution of TRMC signals. A degradation pathway has been determined by identification of intermediate products by chromatography and EPR, results show different intermediate species. In particular EPR confirms the presence of NO^2? paramagnetic centers and shows two novel N centered paramagnetic centers. A decrease of the degradation rate is observed with increase of carboxylic acid chain length.     

交叉设计——Marc &Chantal Design

Marc&Chantal Design 事务所是1993年在香港设立的,三位创始人Marc Brulhart、MarcCansier 和 Chantal Rechaussat 都是香港设计师协会的会员.Marc Cansier 和 Chantal Rechaussat 都曾在巴黎的高等平面设计学校学习艺术与平面设计,Marc Cansier主导品牌设计与平面设计,主要负责一些综合性项目的开发和形成一套公司的设计策略,他在品牌与室内设计方面的经验,使他的设计团队能够综合运用平面、室内及多媒体等交叉设计学科,为客户提交整体的创新的设计方案.     

Influence of fermentation temperature on volatile thiols concentrations in Sauvignon blanc wines

The effect of Saccharomyces cerevisiae strains on the amount of 4-mercapto-4-methylpentan-2-one, a major varietal aroma of Sauvignon blanc wines, was demonstrated by previous research work. However, the influence of different alcoholic fermentation parameters on the levels of volatile thiols (4-mercapto-4-methylpentan-2-one, 3-mercaptohexan-1-ol and 3-mercaptohexyl acetate) in wines has not yet been investigated. The impact of fermentation temperature on the final amount of volatiles thiols and on some other analytical parameters (ethanol, total acidity, residual sugars, volatile acidity) was determined in a model medium and in grape juice. Interaction between fermentation temperature and yeast strain was also tested. The fermentation temperature influenced the amount of volatile thiols irrespective of the yeast strain used. The final levels of 4MMP and 3MH in model medium and in wines were higher when the alcoholic fermentation is conducted at 20 degrees C than at 13 degrees C. The 3MHA, which was correlated with the amount of 3MH determined in wines, was also higher when the alcoholic fermentation was conducted at 20 degrees C. From a technological point of view, the choice of yeast strain and fermentation temperature has a decisive influence on the concentrations of the varietal aromas of Sauvignon blanc wines.     

在腐植酸上二氧化氮光敏还原制备亚硝酸

研究结果表明,土壤和其他含有腐植酸的表面,具有一种能产生还原表面物质的有机表面光化学,而这种还原表面物质可以选择性地与二氧化氮反应。亚硝酸形成的表观速率可以解释最近观察到的白天在边界层中亚硝酸高浓度现象,亚硝酸的光分解占整个羟基自由基源的60%。我们认为这种在腐植酸上的光诱导亚硝酸产物对最低对流层的化学过程有潜在的重要影响。     

Building ubiquitous QoC-aware applications through model-driven software engineering

As every-day mobile devices can easily be equipped with multiple sensing capabilities, ubiquitous applications are expected to exploit the richness of the context information that can be collected by these devices in order to provide the service that is the most appropriate to the situation of the user. However, the design and implementation of such context-aware ubiquitous appplications remain challenging as there exist very few models and tools to guide application designers and developers in mastering the complexity of context information. This becomes even more crucial as context is by nature imperfect. One way to address this issue is to associate to context information meta-data representing its quality. We propose a generic and extensible design process for context-aware applications taking into account the quality of context (QoC). We demonstrate its use on a prototype application for sending flash sale offers to mobile users. We present extensive performance results in terms of memory and processing time of both elementary context management operations and the whole context policy implementing the Flash sale application. The cost of adding QoC management is also measured and appears to be limited to a few milliseconds. We show that a context policy with 120 QoC-aware nodes can be processed in less than 100 ms on a mobile phone. Moreover, a policy of almost 3000 nodes can be instantiated before exhausting the resources of the phone. This enables very rich application scenarios enhancing the user experience and will favor the development of new ubiquitous applications.