法国的绿道概念,孰新孰旧?

首先列举了国际理论界对绿道概念进行的诠释,研究工作的重点包含生态、社会经济及综合意义等不同方面,但共同目标是给绿道规划寻找具有可参考性的建议.对法国的绿道概念"特拉梅韦尔特(trame verte)"的演变进行了综述,详细阐述了法国绿道概念从出生、衰落、概念的回归,到今天概念中融和可持续发展的理念.城市中的环境问题和生物多样性的退化是贯穿在整个概念演变过程中的主要因素,并直接促生了法国对绿道概念进行立法.对这项立法的原创件和有效性的评估认为,从前所未有地将绿道概念写入法律的角度,这项法律是一项创新,但是由于立法是在区域层面,而不是当地的执行层面,从而对这项法律能否真正有效提出质疑.     

Determination of Furan Fatty Acids in Food Samples

Furan fatty acids (F-acids) are valuable bioactive compounds found at low concentrations in food. A method for the quantitative determination of saturated F-acids in food is reported. The sample preparation is based on accelerated solvent extraction, transesterification into methyl esters and silver ion chromatography (20% AgNO₃ in silica, 1% deactivated) of the resulting methyl esters. There then follows determination of the enriched F-acid methyl (or ethyl) esters by GC/EI-MS in the selected ion monitoring (SIM) mode. The 9-(3-methyl-5-pentylfuran-2-yl)-nonanoic acid ethyl ester (9M5-EE) was used as an internal standard for recovery checks. The limit of detection was 11 pg, and the recovery rate of the silver ion chromatography was 85% (n = 5). Further F-acid standards were used for evaluation of individual SIM-responses. Application of the method to various biological samples gave the following results: champignons (n = 2) contained 1.7 or 2.5 mg/100 g dry weight F-acids, while fish oil capsules (n = 5) contained between 18 and 234 mg/100 g oil F-acids distributed over up to seven F-acids. The concentrations and patterns were different to fresh fish. Accordingly, fish oil supplements seem to be a minor source for F-acids compared to (fresh) fish. Organic butter samples (n = 4) contained about twice the amount of F-acids when compared with conventional butter (n = 5).     

Structural insight into iodide uptake by AFm phases

The ability of cement phases carrying positively charged surfaces to retard the mobility of (129)I, present as iodide (I(-)) in groundwater, was investigated in the context of safe disposal of radioactive waste. (125)I sorption experiments on ettringite, hydrotalcite, chloride-, carbonate- and sulfate-containing AFm phases indicated that calcium-monosulfate (AFm-SO(4)) is the only phase that takes up trace levels of iodide. The structures of AFm phases prepared by coprecipitating iodide with other anions were investigated in order to understand this preferential uptake mechanism. X-ray diffraction (XRD) investigations showed a segregation of monoiodide (AFm-I(2)) and Friedel's salt (AFm-Cl(2)) for I-Cl mixtures, whereas interstratifications of AFm-I(2) and hemicarboaluminate (AFm-OH-(CO(3))(0.5)) were observed for the I-CO(3) systems. In contrast, XRD measurements indicated the formation of a solid solution between AFm-I(2) and AFm-SO(4) for the I-SO(4) mixtures. Extended X-ray absorption fine structure spectroscopy showed a modification of the coordination environment of iodine in I-CO(3) and in I-SO(4) samples compared to pure AFm-I(2). This is assumed to be due to the introduction of stacking faults in I-CO(3) samples on one hand and due to the presence of sulfate and associated space-filling water molecules as close neighbors in I-SO(4) samples on the other hand. The formation of a solid solution between AFm-I(2) and AFm-SO(4), with a short-range mixing of iodide and sulfate, implies that AFm-SO(4) bears the potential to retard (129)I.     

Nanopatterning of Anionic Nanoparticles based on Magnetic Prussian‐Blue Analogues

Prussian‐blue analogues (PBA) are a family of molecule‐based magnetic compounds of general formula A_xM_y[M’(CN)₆]_z, whose magnetic properties can be tuned by an external stimulus. This tunability makes PBA good candidates for their integration into new electronic or spintronic devices. As a previous step to accomplish this integration, PBA need to be deposited onto surfaces in controllable ways and if possible into specific positions on the surface. Even though the study of PBA has traditionally been limited to bulk, lately they have also been processed as nanoparticles (NPs). Here an efficient approach is presented for the accurate deposition and organization of PBA‐NPs of different sizes (from ～6 to ～25 nm) over silicon surfaces. The approach used in this work, relies on a combination of surface functionalization with local oxidation nanolithography (LON) and uses electrostatic interactions between PBA‐NPs and a charged self‐assembled monolayer patterned on specific parts of the silicon surface. By using atomic force microscopy (AFM), magnetometry, infrared spectroscopy (IR) and auger electron spectroscopy (AES) we show that the deposition process does not affect NPs properties. In addition, we present a study on the evolution of AFM nanolithographed SiO₂ patterns under sonication.     

Application of stochastic multiattribute analysis to assessment of single walled carbon nanotube synthesis processes

The unprecedented uncertainty associated with engineered nanomaterials greatly expands the need for research regarding their potential environmental consequences. However, decision-makers such as regulatory agencies, product developers, or other nanotechnology stakeholders may not find the results of such research directly informative of decisions intended to mitigate environmental risks. To help interpret research findings and prioritize new research needs, there is an acute need for structured decision-analytic aids that are operable in a context of extraordinary uncertainty. Whereas existing stochastic decision-analytic techniques explore uncertainty only in decision-maker preference information, this paper extends model uncertainty to technology performance. As an illustrative example, the framework is applied to the case of single-wall carbon nanotubes. Four different synthesis processes (arc, high pressure carbon monoxide, chemical vapor deposition, and laser) are compared based on five salient performance criteria. A probabilistic rank ordering of preferred processes is determined using outranking normalization and a linear-weighted sum for different weighting scenarios including completely unknown weights and four fixed-weight sets representing hypothetical stakeholder views. No single process pathway dominates under all weight scenarios, but it is likely that some inferior process technologies could be identified as low priorities for further research.     

Correlation of cyclic voltammetry behaviour and photooxidative properties of indoprofen and its photoproducts

The electrochemical behaviour of indoprofen (INP) and its photoproducts was investigated in acetonitrile containing tetrabutylammonium hexafluorophosphate at a Pt or Cv ultramicro-electrodes. These photosensitizers (PS) undergo irreversible oxidation yielding at first a radical cation PS⁺ and more or less reversible reductions through monoelectronic exchange involving a radical anion PS⁻. By varying the potential scan speed, the stabilities of the radical anions were evaluated. The determination of the redox potential and Rehm-Weller's equation shows the high exergonicity of the oxidative photodamagings whatever is the compound PS. The difference in DNA photosensitizing properties could rather be related to a kinetic control and then to the relative stabilities of the radical anions PS⁻. Cyclic voltammetry was found powerful in order to get a new insight in the photosensitizing properties of drugs.     

Indirect urea electrooxidation by nickel(III) in alkaline medium: From kinetic and mechanism to reactor modeling

This study consists in the determination of two kinetic laws of urea oxidation (UO) and electrooxidation (UEO) in alkaline media on nickel(III). Two kinds of active sites were examined, the first one derived from a Ni(OH)₂ powder and the second from a massive nickel electrode. Partial orders of nickel(III) (two for UO and five UEO) enable to conclude about (i) the urea adsorption on two nickel(III) sites and (ii) that a multistep oxidation of urea occurs involving five nickel(III) site electroregenerations. A multipathway mechanism is also proposed to explain UEO facilitated by the nickel(III)/nickel(II) mediation system, and to predict the by-products' formation previously identified ($\mathrm{N}{\mathrm{O}}_2^{-},\mathrm{N}{\mathrm{H}}_3,\mathrm{OC}{\mathrm{N}}^{-},\mathrm{C}{\mathrm{O}}_3^{2-}$). At last, a model combining the UEO kinetic law previously established, with diffusive and convective transport phenomena was developed. A consistent correlation (maximum deviation of 6%) between laboratory electrolysis results with the model' predictions was obtained under different operating conditions, enabling the validation of this model.     

Strained Dehydrogenative Ring Closure of Phenylcarbazoles

What does it take to force a rigid and strained dehydrogenative ring closure, for example, in phenylcarbazoles? Since the works of Buchwald and Fagnou, palladium‐catalysed ring‐closing dehydrogenative reactions are legion, but will not operate when the strain at the reductive elimination stage becomes too large. We propose here a “muscled up” super‐oxidative palldium‐catalysed C H activation method for the ring closure of strained phenylcarbazoles.