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101.
Ann Heylighen Monika Rychtáriková Gerrit Vermeir 《Universal Access in the Information Society》2010,9(3):283-292
Inclusive design aims at objects and environments that are accessible, usable and comfortable for all people throughout their
entire lifespan. In architecture, this aim is usually associated with physical accessibility. Yet acoustic qualities may considerably
impact usability and comfort as well, especially in spaces for listening. This case study explores the notion of acoustic
comfort for all in the context of university education. One auditorium, situated in a historic building and subject to renovation
in the near future, is studied in detail: acoustic obstacles are identified in collaboration with user/experts and are measured
in situ; specific interventions are proposed in consultation with building professionals, technicians and conservation specialists
and are tested using dedicated acoustic simulation software. The study draws attention to the importance of acoustic comfort
for all and offers a first view of which solutions are possible and desirable and how these can be obtained. 相似文献
102.
Monika Haros Nils-Gunnar Carlsson Annette Almgren Marie Larsson-Alminger Ann-Sofie Sandberg Thomas Andlid 《International journal of food microbiology》2009,135(1):7-14
The growing awareness of the relationship between diet and health has led to an increasing demand for food products that support health above and beyond providing basic nutrition. Probiotics are live organisms present in foods, which yield health benefits related to their interactions with the gastrointestinal tract. Phytases are a subgroup of phosphatases that catalyse the desphosphorylation of phytate, which reduces its negative impact on mineral bioavailability, and generates lower inositol phosphates. The aims of this investigation were to (i) study the ability of the probiotic candidate Bifidobacterium pseudocatenulatum to degrade phytate in synthetic medium, to (ii) identify the lower inositol phosphates generated, to (iii) study its survival under conditions mimicking gastrointestinal passage and finally to (iv) assess adhesion of the bacteria to Caco-2 cells. The first steps of InsP6 degradation by B. pseudocatenulatum phytate-degrading enzyme/s were preferentially initiated at the DL-6-position and 5-position of the myo-inositol ring. It suggests that the main InsP6 degradation pathway by B. pseudocatenulatum by sequential removal of phosphate groups was D/L-Ins(1,2,3,4,5)P5 or D/L-Ins(1,2,3,4,6)P5; D/L-Ins(1,2,3,4)P4; to finally Ins(1,2,3)P3 and D/L-Ins(1,2,4)P3/D/L-Ins(1,3,4)P3. This human strain also showed a notable tolerance to bile as well as a selective adhesion capacity (adhesion to control surfaces was zero), to human intestinal Caco-2 cells comparable to the commercial probiotic B. lactis. The phytate-degrading activity constitutes a novel metabolic trait which could contribute to the improvement of mineral absorption in the intestine as a nutritional probiotic feature with potential trophic effect in human gut. 相似文献
103.
A new strategy to improve alkyd/acrylic compatibilization in waterborne hybrid dispersions 总被引:3,自引:0,他引:3
Monika Goikoetxea 《Polymer》2010,51(23):5313-5317
Grafting of alkyd resin to the acrylic polymer is needed to fully exploit the possibilities of these hybrids; but in the current technology, grafting is accompanied by an important reduction of the unsaturated groups of the alkyds, which adversely affects the curing of the film and its properties. A novel strategy that overcomes these limitations is presented. The strategy is based on the use of alkyd resin functionalized with methacrylic groups, that substantially improved the incorporation of the resin to the growing acrylic polymer chain, and the polymer particle homogeneity, without decreasing the degree of unsaturation in the alkyd resin. 相似文献
104.
Michele Leonardi Urszula Skomra Monika Agacka Anna Stochmal Katarzyna E. Ambryszewska Wieslaw Oleszek Guido Flamini Luisa Pistelli 《International Journal of Food Science & Technology》2013,48(8):1770-1774
Polish cultivars of hop (Humulus lupulus L.) are well known as aroma and bitter raw material in the brewing industry. To characterise four popular Polish hop cultivars, Lubelski (Lublin), Marynka, Sybilla and Iunga (also known as Junga), the essential oil profiles were determined by gas chromatography/flame ionisation detector (GC‐FID) and gas chromatography/chemical ionisation mass spectrometry (GC‐CIMS) and the alpha/beta acids amounts by high‐performance liquid chromatography/diode array detector (HPLC‐DAD) analysis. In addition, the multivariate statistical analysis of the volatile profiles was performed. The results obtained evidenced qualitative and quantitative differences between the four cultivars studied and the foreign hops described in the literature. Lubelski and Iunga showed the typical chemical profile of the fine‐aroma and high‐alpha cultivars, respectively. In Marynka and Sybilla, the average amounts of alpha acids were similar to the bitter hops, but with a volatile profile characteristics of the fine‐aroma and aroma cultivars respectively. 相似文献
105.
Redox-active films have been generated via electrochemical reduction in a solution containing palladium(II) acetate and [C60]fullerene, or derivatives of C60. The C60 derivatives include piperazine (piperazine-C60), pyrrolidine (CH3-pyr-C60), and a pyrrolidine salt, [(CH3)2-pyr-C60]+ attached to the fullerene unit. In these films, fullerene moieties are covalently bonded to palladium atoms to form a polymeric network. The polymer yields involving the piperazine and pyrrolidine derivatives of C60 are significantly lower than the yield of the C60/Pd film. The CH3-pyr-C60/Pd and [(CH3)2-pyr-C60]+/Pd films are electrochemically active in the negative potential region due to the reduction of the fullerene moiety. Reduction of the CH3-pyr-C60/Pd film is accompanied by the transport of supporting electrolyte cations from the solution into the film. In the first reduction step of the [(CH3)2-pyr-C60]+/Pd film, both cations and anions of the supporting electrolyte are involved. The piperazine-C60/Pd film exhibits electrochemical activity at both negative and positive potentials. In the negative potential region, reduction of the fullerene cage takes place. Oxidation of the piperazine moiety is responsible for the observed current in the positive potential range. Here, the oxidation process of this polymer is significantly influenced by the presence of metallic palladium particles in the film. 相似文献
106.
The aim of this article is to present results of an experimental campaign performed on a full-scale facility provided with a double-skin façade. The behaviour of this architectural concept is tested under controlled climatic conditions. A summer case is scrutinised under different configurations: variation of the airflow through the double-skin façade and different angle of the solar shading device. This paper describes the experimental conditions, as well the test facility and the tested façade element. The results show the temperatures of the test cell and the façade and how they depend on the climatic conditions and the sun-shading device blade angles. One objective of this research was to measure and provide extensive data set detailing air and surface temperatures on the double-skin façade, together with airflow rates and air velocities. The experiments are fully described so that the results can be used for the validation of numerical models dealing with ventilated double-skin façades with venetian sun-shading device. 相似文献
107.
Oxidation and Carburization of High Alloyed Materials for Cracking Tubes – Part 2: The Carburization Behaviour in Oxygen and Carbon Containing Atmospheres with High Carbon Activity Carburization tests have been carried out with the casting materials (German Designation) Werkstoff-Nr. 1.4848, 1.4857, 2.4813 and an experimental 25/20/5-CrNiSi melt, and with the wrought materials Werkstoff Nr. 1.4301 and 1.4848 in CO-CO2 mixtures with ac = 1, and in humid natural gas with ac > 1 between 1000 and 1200° C. At temperatures below appr. 1050° C oxide layers formed are analogous to those formed in air (substrate/Cr2O3/(Mn, Fe)Cr2O4) which prevent carburization. Carburization takes place only after the protective oxide layer has been destroyed. In this context several mechanisms of destruction must be considered, i.e. (a) by chemical reaction (transformation of oxide into carbide, reduction of oxide), (b) by mechanical stresses (temperature fluctuation, growth of graphite layers, creep deformation). Reduction processes are encountered with Fe-rich oxide layers only. Scale layers rich in chromium oxide are transformed into carbide above appr. 1050° C in gases with ac = 1, depending on the CO partial pressure. The rate of this transformation strongly depends on carbon activity in the gas phase. When graphite is deposited on the surface the transformation occurs at a high rate, while it is rather slow even at ac = 1 when no graphite is deposited. Deposited graphite may have a mechanically destructive effect, too, because it penetrates into cracks and pores in the oxide layer and thus produces spalling of oxide particles. When the surface of the cast material is porous particles of the substrate may become detached, too. This goes to explain the poor behaviour of tubes with as cast surfaces in cracking reactors. The positive effect of silicon is due to the formation of protective silica layers between metal and Cr2O3 and metal and external carbide layer respectively. In order to form a continuous silica layer the Si content in the material must not be below a cricital value. 相似文献
108.
Characterization of steel mill electric-arc furnace dust 总被引:4,自引:0,他引:4
Sofilić T Rastovcan-Mioc A Cerjan-Stefanović S Novosel-Radović V Jenko M 《Journal of hazardous materials》2004,109(1-3):59-70
In order to make a complete characterization of electric-arc furnace (EAF) dust, as hazardous industrial waste, and to solve its permanent disposal and/or recovery, bearing in mind both the volumes formed in the Croatian steel industry and experiences of developed industrial countries, a study of its properties was undertaken. For this purpose, samples of EAF dust, taken from the regular production process in the Zeljezara Sisak Steel Mill between December 2000 and December 2001, were subjected to a series of tests. The chemical composition of EAF dust samples was investigated by means of a several different analytical methods. The results from the chemical analysis show that the approximate order of abundance of major elements in EAF dusts is as follows: Fe, Zn, Mn, Ca, Mg, Si, Pb, S, Cr, Cu, Al, C, Ni, Cd, As and Hg. Granular-metric composition of single samples was determined by applying sieve separation. Scanning electron micro-structural examination of EAF dust microstructure was performed and results indicated that all twelve EAF dusts were composed of solid spherical agglomerates with Fe, Zn, Pb, O, Si and Ca as the principal element. The investigation of grain morphology and the mineralogical composition of EAF dust were taken by combination of high resolution Auger electron spectroscopy (HR AES), X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction analysis. The analysis of XPS-spectra determined the presence of zinc in the form of ZnO phase and the presence of lead in the form of PbO phase, i.e. PbSO3/PbSO4 forms. The results of the X-ray diffraction phase analysis show that the basis of the examined EAF dust samples is made of a mixture of metal oxides, silicates and sulphates. The metal concentration, anions, pH value and conductivity in water eluates was determined in order to define the influence of EAF dust on the environment. 相似文献
109.
Detection of skin cancer by classification of Raman spectra 总被引:1,自引:0,他引:1
Sigurdsson S Philipsen PA Hansen LK Larsen J Gniadecka M Wulf HC 《IEEE transactions on bio-medical engineering》2004,51(10):1784-1793
Skin lesion classification based on in vitro Raman spectroscopy is approached using a nonlinear neural network classifier. The classification framework is probabilistic and highly automated. The framework includes a feature extraction for Raman spectra and a fully adaptive and robust feedforward neural network classifier. Moreover, classification rules learned by the neural network may be extracted and evaluated for reproducibility, making it possible to explain the class assignment. The classification performance for the present data set, involving 222 cases and five lesion types, was 80.5%+/-5.3% correct classification of malignant melanoma, which is similar to that of trained dermatologists based on visual inspection. The skin cancer basal cell carcinoma has a classification rate of 95.8%+/-2.7%, which is excellent. The overall classification rate of skin lesions is 94.8%+/-3.0%. Spectral regions, which are important for network classification, are demonstrated to reproduce. Small distinctive bands in the spectrum, corresponding to specific lipids and proteins, are shown to hold the discriminating information which the network uses to diagnose skin lesions. 相似文献
110.
Szczubiałka K Jankowska M Nowakowska M 《Journal of materials science. Materials in medicine》2003,14(8):699-703
Novel random terpolymers of N-isopropylacrylamide (NIPAM), sodium 2-acrylamido-2-methyl-1-propanesulfonate (AMPS), and cinnamoyloxyethylmethacrylate (CEMA) were synthesized by free radical copolymerization using AIBN as an initiator. Five terpolymers were obtained by copolymerization of the monomer mixtures containing a fixed amount of 10 mol % of AMPS while the content of CEMA ranged from 5 to 25 mol % and was changed in 5 mol % increments. The terpolymers obtained are water-soluble. Because of their amphiphilic nature they undergo self-organization in the aqueous solution with the formation of micelles capable of solubilizing sparingly water soluble organic compounds, such as drugs. The terpolymers are susceptible to three external stimuli, i.e. temperature, ionic strength and UV light. Due to the presence of NIPAM in the terpolymers they display the lower critical solution temperature (LCST), the presence of AMPS makes them sensitive to the ionic strength of the solution, while the light-responsiveness of the terpolymers is due to the presence of cinnamoyl chromophores, which undergo photodimerization when irradiated with UV light at about 280 nm. Application of any of these stimuli alone or in combination with other stimuli allows changing the copolymer properties in a controlled way. 相似文献