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The research being undertaken seeks to achieve a better understanding of the richness of microclimatic characteristics in outdoor urban spaces, and the comfort implications for the people using them. The underlying hypothesis is that these conditions influence people’s behaviour and usage of outdoor spaces. The initial results demonstrate that a purely physiological approach is inadequate in characterising comfort conditions outdoors, and an understanding of the dynamic human parameter is necessary in designing spaces for public use. The thermal environment is indeed of prime importance influencing people’s use of these spaces, but psychological adaptation (available choice, environmental stimulation, thermal history, memory effect, expectations) is also of great importance in such spaces that present few constraints. 相似文献
34.
Pauline E. Key Paul M. Finglas Nick Coldham Nigel Botting Mark F. Oldfield Roger Wood 《Food chemistry》2006
This quality assurance (proficiency testing) scheme was commissioned to enable the Food Standards Agency (FSA) to determine the quality of analytical results submitted by researchers measuring the concentrations of phytoestrogens in foods and biological fluids in FSA-funded research projects, and also, to demonstrate that FSA-funded laboratories are producing consistent and precise results. Non-FSA-funded laboratories from around the world were also invited to join in the scheme to increase the number participants. A secondary objective was to highlight the most successful methodologies used to analyse phytoestrogens. 相似文献
35.
During sporulation in the ascomyceteous fungus Schizosaccharomyces pombe, diploid cells undergo differentiation into asci containing four haploid ascospores, which are highly resistant to environmental stresses. Although the morphogenetic processes involved in ascospore formation have been studied extensively, little is known about the molecular mechanism that ensures the release of mature ascospores from the ascus, allowing their dispersal into the environment. Recently, we identified Agn2p as the paralogue of the characterized endo-(1,3)-alpha-glucanase Agn1p, and observed that asci deleted for agn2 are defective in ascospore dispersal. Here, we focus on the cellular and biochemical functions of Agn2p. By placing agn2 under the control of an inducible promoter, we show that expression of agn2 is required for the efficient release of ascospores from their asci. Furthermore, we characterize the enzyme activity of purified recombinant Agn2p and show that Agn2p, like Agn1p, is an endo-(1,3)-alpha-glucanase that produces predominantly (1,3)-alpha-glucan pentasaccharides. Finally, we demonstrate that exogenous addition of purified Agn2p liberated the ascospores from asci deleted for agn2. We propose that Agn2p participates in the endolysis of the ascus wall by hydrolysing its (1,3)-alpha-glucan, thereby assisting in the release of ascospores. 相似文献
36.
Vlad C Lindner K Karreman C Schildknecht S Leist M Tomczyk N Rontree J Langridge J Danzer K Ciossek T Petre A Gross ML Hengerer B Przybylski M 《Chembiochem : a European journal of chemical biology》2011,12(18):2740-2744
Gas-phase protein separation by ion mobility: With its ability to separate the Parkinson's disease protein α-synuclein and its autoproteolytic products-despite the small concentrations of the latter-ion-mobility MS has enabled the characterization of intermediate fragments in in vitro oligomerization-aggregation. In particular, a possible key fragment, the highly aggregating C-terminal fragment, αSyn(72-140), has been revealed. 相似文献
37.
Yunxia Yang Craig M. Brown Chunxia Zhao Alan L. Chaffee Burke Nick Dongyuan Zhao Paul A. Webley Jacob Schalch Jason M. Simmons Yun Liu Jae-Hyuk Her C.E. Buckley Drew A. Sheppard 《Carbon》2011,(4):1305-1317
Ordered microporous carbons containing dispersed platinum nanoparticles were fabricated and chosen as suitable models to investigate micro-structure development and hydrogen transport properties of zeolite-templated carbons. X-ray photoelectron spectroscopy analysis revealed that the enhanced heat of adsorption is related to the narrow micro-channels templated from the zeolite and the presence of certain CO groups on the carbon. The lack of a well-defined and intense rotational transition line and the persistent broad H2 recoil spectrum in neutron scattering results suggests a distribution of binding sites. Most interestingly, hydrogen diffusion occurs on two time scales, consisting of a fast liquid-like jump diffusion on the timescale of picoseconds along with an even faster bulk-like diffusion. The liquid-like motion is characterized by a diffusion constant of (2.1 ± 0.3) × 10−8 m2/s with an activation energy of ca. 77 K; both values indicate somewhat lower mobility than similar dynamics of H2 on nanotubes, activated carbon XC-72, or Grafoil, yet greater mobility than that of bulk liquid. These unusual characteristics for hydrogen in carbons are believed to arise from the network of narrow pores in this zeolite-templated image of the zeolite. In fact, the diffusion constants of the templated carbons are extremely similar to those measured for zeolite 13X. 相似文献
38.
Nick D. Austin Nikolaos V. Sahinidis Ivan A. Konstantinov Daniel W. Trahan 《American Institute of Chemical Engineers》2018,64(1):104-122
In this article, we investigate reaction solvent design using COSMO‐RS thermodynamics in conjunction with computer‐aided molecular design (CAMD) techniques. CAMD using COSMO‐RS has the distinct advantage of being a method based in quantum chemistry, which allows for the incorporation of quantum‐level information about transition states, reactive intermediates, and other important species directly into CAMD problems. This work encompasses three main additions to our previous framework for solvent design (Austin et al., Chem Eng Sci. 2017;159:93–105): (1) altering the group contribution method to estimate hydrogen‐bonding and non‐hydrogen‐bonding σ‐profiles; (2) ab initio modeling of strong solute/solvent interactions such as H‐bonding or coordinate bonding; and (3) solving mixture design problems limited to common laboratory and industrial solvents. We apply this methodology to three diverse case studies: accelerating the reaction rate of a Menschutkin reaction, controlling the chemoselectivity of a lithiation reaction, and controlling the chemoselectivity of a nucleophilic aromatic substitution reaction. We report improved solvents/mixtures in all cases. © 2017 American Institute of Chemical Engineers AIChE J, 63: 104–122, 2018 相似文献
39.
Theodore Karoubalis Kostas Adaos George Ph. Alexiou Nick Kanopoulos 《International Journal of Circuit Theory and Applications》1995,23(6):587-598
This paper describes an efficient technique for the design of fault-secure VLSI circuits based on differential cascode voltage switch (DCVS) logic. We propose a new synthesis method for constructing DCVS circuits with a near-optimal transistor count based on binary decision diagrams (BDDs). the time and memory resources required are very low, making the technique practical even for PC-based synthesis tools. This method is the basis for a CAD tool that allows automatic synthesis of fault-secure circuits based on the DCVS technology. We finally present an improved design and implementation of a 2's complement serial/parallel multiplier as an application of the proposed technique and algorithm. 相似文献
40.
Jared A. StoegerCharitomeni M. Veziri Miguel PalominoAvelino Corma Nick K. KanellopoulosMichael Tsapatsis Georgios N. Karanikolos 《Microporous and mesoporous materials》2012,147(1):286-294
Continuous films comprised of highly c-oriented aluminophosphate AlPO4-5 or cobalt-substituted AlPO4-5 (CoAPO-5) were grown on porous supports and subjected to heat treatment in order to investigate the potential for membrane applications. A study in the early stages of in-plane crystalline intergrowth revealed a potential mechanism for flake-like crystal formation between the original oriented columnar crystals. Variations in metal substitution (AlPO4-5, CoAPO-5), support (glass, silicon, porous alumina), and calcination method (conventional, rapid thermal processing) were chosen to examine the conditions by which structural integrity was compromised following secondary (or tertiary) growth, resulting in reduced membrane functionality. Through the use of rapid thermal processing, the structure debilitation could be partially avoided. The membrane quality was inspected through pervaporation measurements consisting of a liquid hydrocarbon feed of n-heptane and 1,3,5-triisopropylbenzene. By investigating the effect of template removal on the oriented, columnar crystalline structure, useful insight is provided into the potential for the membranes to participate in applications such as molecular separations, catalysis, or host-guest assemblies. 相似文献