Recovery decisions of a producer in a legislative disposal fee environment

The main objectives of the environmental legislation originating from extended producer responsibility (EPR) principle are to lead producers to undertake recovery initiatives for their end-of-use products and to promote environmentally desirable product design. It is still controversial whether current implementations of EPR principle are effective in attaining these objectives. This study seeks to answer the following questions: (1) What is the impact of EPR legislation on the product recovery decisions of producers? (2) How do the redesign opportunities (i.e., design for disassembly) affect the willingness of producers for product recovery? (3) How do the investment needs to start recovery practices and the reluctance of producers to allocate sufficient funds for this purpose affect the optimal recovery decisions? We use stylized economic models to represent the implementation in practice and solving our models we obtain closed form and numerical solutions that help us to see the impact of various parameters on the optimal decisions of a producer. Our findings indicate that redesign opportunities encourage producers for more recovery, however the reluctance of producers to cover the initial investments may substantially reduce the effectiveness of the legislation and the recovery amounts.     

Landmark-Based Registration of Curves via the Continuous Wavelet Transform

This article is concerned with the problem of the alignment of multiple sets of curves. We analyze two real examples arising from the biomedical area for which we need to test whether there are any statistically significant differences between two subsets of subjects. To synchronize a set of curves, we propose a new nonparametric landmark-based registration method based on the alignment of the structural intensity of the zero-crossings of a wavelet transform. The structural intensity is a recently proposed multiscale technique that highlights the main features of a signal observed with noise. We conduct a simulation study to compare our landmark-based registration approach with some existing methods for curve alignment. For the two real examples, we compare the registered curves with FANOVA techniques, and a detailed analysis of the warping functions is provided.     

土水特征曲线(SWCC)的滞回特性模拟研究

为了模拟非饱和土的水力、力学特性在多次降雨、蒸发过程中的变化特性,本文以传统域模型的基本原理为基础,推到得到了一个能够模拟SWCC滞后性的计算模型,该模型计算方法简单,易于通过程序实现,且通过与试验数据和其他模型的计算结果对比,验证了该模型的合理性,同时,这个模型可为研究在复杂吸力变化状态下非饱和土的渗流特性、强度特性以及本构模型的研究打下一定的基础。     

环境化学课程内容体系及教学改革研究

针对目前环境化学课程教学过程中存在的问题,作者结合实践,为适应新型人才培养模式需求,就课程内容建设、教学方法等环节对该课程应采取的具体革新措施提出一些个人看法,以期形成该课程在化学化工专业独特的教学体系。     

Stereoselective synthesis of (−)-synargentolide B

A convergent, enantioselective total synthesis of (?)-synargentolide-B has been accomplished from readily available l-arabinose and d-ethyl lactate by a 10-step sequence involving Still-Gennari olefination, one-pot acidic deprotection/lactonization and olefin cross-metathesis reaction as the key step.     

IoT & environmental analytical chemistry: Towards a profitable symbiosis

In a constantly evolving world, where the rising population and increased social awareness have led to a higher concern for the environment, research in this field (most notably in Environmental Analytical Chemistry) should take advantage of the great opportunities offered by new technologies such as Internet of Things (IoT) and Cloud-based services. Both of them are especially suitable when chemical sensors and related devices are used in the continuous in-line monitoring of environmental parameters. In this sense, it is very important to obtain spatially distributed information of these parameters as well as their temporal evolution.In this work, a friendly approach to IoT world for environmental applications is carried out. To get a global vision of these concepts, the starting point is their historical evolution. New trends are also identified along with associated challenges and potential threats. Furthermore, not only there will be (in the near future) a need to rely on distributed analytical sensors but also on even more complex, lab-based techniques that are connected to the IoT through appropriate mechanisms. A revision of the recent literature relating IoT with environmental issues has also been performed, the most relevant contributions being discussed. Finally, the need of a mutual cooperation between IoT and Environmental Analytical Chemistry is outlined and commented in detail. Ignoring the new capabilities offered by Cloud computing and IoT environments is no further an option. In this sense, the main contribution of this paper consists of highlighting the fact that the wiser course is to embrace these opportunities consciously for mutual profit.     

A new adsorbent for trace organic analysis in environmental samples

Summary Graphite fluoride has been evaluated as an adsorbent for use in concentrating organic impurities in air and water samples. This material has been shown to yield large breakthrough volumes for most organics and should be useful for trace analysis in environmental chemistry.     

P－矩阵荧光法同时测定苯酚和十二烷基苯磺酸钠

在研究了苯酚(Ph-OH)和十二烷基苯磺酸钠(SDBS)荧光性质的基础上,以P-矩阵计算混合体系中苯酚和十二烷基苯磺酸钠。方法灵敏度高,选择性好,简便快速,应用于环境水样测定结果令人满意。     

Highly sensitive impedance-based propene sensor using stabilized zirconia and zinc oxide sensing-electrode

Aimed at an environmental monitoring of hydrocarbons (HCs), a new-type impedancemetric sensor was fabricated by using an yttria-stabilized zirconia (YSZ) tube and ZnO sensing-electrode (SE). The fabricated tubular sensor was examined for detection of low concentrations of propene (C₃H₆) in the presence of 1.35 vol.% H₂O and 400 ppm CO₂ at 600 °C. As a result, it was found that the present sensor could detect the low concentrations of C₃H₆ in the range of 0.05–0.8 ppm and the sensitivity varied linearly with C₃H₆ concentration. In addition, the C₃H₆ sensitivity was almost invariant with the changes in the concentration of water vapor and the interferences to other gases, such as NO₂, NO, H₂, CO and CH₄, were insignificant.     

Towards green synthesis of nanoparticles: From bio-assisted sources to benign solvents. A review

Current advancements in green synthesis of materials especially nanoparticles have led to conservation of natural and non-renewable resources along with reduction in environmental pollution. Development of cost-effective, simple and eco-friendly routes for the synthesis of nanoparticles is very important. All over the world, a wide variety of biogenic sources have been put to trial as a source of green agents to facilitate synthesis process. In addition to this, environmentally benign solvents are also being used these days in order to promote green synthesis. In this review, an attempt has been made to familiarise the readers with the different green routes for the synthesis of nanoparticles.