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951.
Sara R Jaeger Karen L Rossiter Karen Lau 《Journal of the science of food and agriculture》2005,85(3):480-488
To explore how consumers perceive novel and familiar fruit, repertory grid interviews were carried out with 60 New Zealand women. Participants described their perceptions of nine fruit varying in familiarity. The data analysis established a two‐dimensional stimuli space that separated samples with respect to familiarity and the amount of preparation required. Fruit that was familiar was characterised as being well liked, easily available in shops and by a number of different use situations. The primary association with novel fruit was that it was expensive. The participants could not readily think of use situations for fruit they were unfamiliar with. Consumers were separated into groups according to the trait of food neophobia, which pertains to an individual's stable propensity to approach or avoid novel foods. When comparing the most neophobic (n = 14; avoids novel foods) and most neophilic (n = 14; approaches novel foods), individuals perceptual differences were uncovered pertaining to which of the fruit were considered novel and to the suitability of some usage situations (cooking and for children). This finding contributed to the growing evidence of the relationship between food neophobia and consumers' everyday food‐related behaviour. Copyright © 2004 Society of Chemical Industry 相似文献
952.
953.
Marika Křepelová‐DROR Ilan Hammel Isaac Meilijson 《Microscopy research and technique》2014,77(1):1-10
ABSTRACT The size distribution of vesicles exocytosed from secretory cells displays quantal nature, vesicle volume is periodic multi‐modal, suggesting that these heterogeneous vesicles are aggregate sums of a variable number of homogeneous basic granules. Whether heterogeneity is a lumping‐together artifact of the measurement or an inherent intra‐cell feature of the vesicles is an unresolved question. Recent empirical evidence will be provided for the quantal nature of intra‐cell vesicle volume, supporting the controversial paradigm of homotypic fusion: basic cytoplasmic granules fuse with each other to create heterogeneously sized vesicles. An EM‐algorithm‐based method is presented for the conversion of multi‐modal to quantal data that provides as by‐product estimates of means and variances of basic granule packaging. Microsc. Res. Tech. 77:1–10, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
954.
The effects of harvest maturity and ripening on the chemical composition and sensory characteristics of ‘McIntosh’ and ‘Spartan’ apple juice were evaluated. Juice was extracted from fruit harvested at seven weekly intervals beginning 3–4 weeks before commercial harvest and from fruit held in air storage (1°C) for 1 to 3 months. Internal ethylene concentration and starch index were used as maturity indices. Principal component analysis of juice data (pH. titratable acidity, organic acids, soluble solids, sugars, phenols, turbidity, and Hunterlab colour) showed a distinctive maturity effect on the characteristics of juice extracted from fruit immediately after harvest or after storage. Triangle testing showed aroma and flavour differences in both ‘McIntosh’ and ‘Spartan’ to be first discernable when ethylene was first detected (internal ethylene concentration ≥ 0.1 μl litre?1) and starch hydrolysis evident (starch index 3.0–5.0 for ‘McIntosh’, 1.5–3.0 for ‘Spartan’), or after 2–3 months of air storage. Sensory profiling of fruity aroma, total aroma, fruit flavour by mouth, sweetness, and sourness in the juices showed increased fruitiness and sweetness and decreased sourness with advancing maturity. 相似文献
955.
T.H. Muster A. Trinchi T.A. Markley D. Lau P. Martin A. Bradbury A. Bendavid S. Dligatch 《Electrochimica acta》2011,(27):9679
Many 21st century technological solutions are reliant on the development of new materials with improved properties, and increasingly on materials that can be optimised to perform more than one function. High-throughput and combinatorial methodologies are being used more frequently to discover and design improved materials in a time efficient manner for a variety of applications. A number of technological challenges involve the field of electrochemistry, such as battery development, electrocatalysis, photocatalysis, corrosion protection, sensor development, photovoltaics and light-emitting materials. This review focuses on the utilisation of high-throughput and combinatorial methods that have incorporated, or are associated with, electrochemical methods. In many cases electrochemical determinations are well-suited for high-throughput methodologies, enabling direct quantitative analysis of properties. However, in other circumstances electrochemical measurements are complicated by additional factors. Hence the limitations of high-throughput and combinatorial electrochemistry are also discussed within. 相似文献
956.
Synthesis of electrochemically-reduced graphene oxide film with controllable size and thickness and its use in supercapacitor 总被引:1,自引:0,他引:1
An electrochemical synthesis method of reducing graphene oxide (GO) under constant potential is reported. Electrochemical technique offers control over reaction parameters such as the applied voltage, electrical current and reduction time; whereas the desired size and thickness of the film can be pre-determined by controlling the amount of precursor GO deposited on the electrode with defined shape and surface area. This synthesis technique produces high quality electrochemically reduced GO (ERGO) film with controllable size and thickness. Electrochemical symmetrical supercapacitors based on ERGO films achieved a specific capacitance of 128 F/g with an energy density of 17.8 Wh/kg operating within a potential window of 1.0 V in 1.0 M NaNO3. The supercapacitor was shown to be stable, retaining ca. 86% of the original specific capacitance after 3500 charge–discharge cycles. The results indicate that this simple synthesis technique for providing graphene-like materials has great potential in various applications such as energy storage. 相似文献
957.
Rui L. Aguiar Diogo Gomes João Paulo Barraca Nuno Lau 《Wireless Personal Communications》2014,76(2):231-244
Mobile robotics is a transforming field that presents a varying set of challenges. The discussion on the autonomy of (self-powered) robots is not settled, and as the communication infrastructure evolves, centralized concepts become more attractive over distributed concepts. This paper presents the CloudThinking architecture applied to intelligent cloud-based robotic operation. CloudThinking offloads most of complex robotic tasks to a central cloud, which retrieves inputs from the environment as a whole in order to instruct the robots to perform its actions. CloudThinking is a natural approach to the orchestration of multiple specialized robotic systems, defining the best mechanisms for reaching a goal. Furthermore, this architecture provides a set of automatic features which can be useful for application developers. These features can fully exploit novel cloud tools development as it becomes available, providing a time-resilient infrastructure of easy upgrade. The resulting approach has the potential to create a different set of market for robotic application developers. 相似文献
958.
The experimental characterisation of electrospun poly(lactic acid) (PLA):poly(ε-caprolactone) (PCL) as drug carriers, at five blend ratios from 1:0, 3:1, 1:1, 1:3 and 0:1, was holistically investigated in terms of their morphological structures, crystallinity levels and thermal properties. A widely used antibiotic tetracycline hydrochloride (TCH) was loaded to prepared fibrous mats at TCH concentrations of 1 and 5 wt%. The additional TCH into PLA:PCL better facilitates the reduction of fibre diameter than polymer blends. Increasing the TCH concentration from 1 to 5 wt% was found to result in only a modest decrease in the crystallinity level, but a significant increase in the crystallisation temperature (T c) for PLA within PLA:PCL blends. The infrared spectra of fibre mats confirm the successful TCH encapsulation into fibrous networks. The first order and Zeng models for drug release kinetics were in better agreement with experimental release data, indicating the release acceleration of TCH with increasing its concentration. In a typical case of PLA:PCL (1:1) loaded with 5 wt% TCH, the fibre mats apparently demonstrate more wrinkled and floppy structures and increased fibre diameters and decreased inter-fibrous spaces after 7-day in vitro fibre degradation, as opposed to those obtained after 3-h degradation. 相似文献
959.
P. Klason G. J. Kok N. Pelevic M. Holmsten S. Ljungblad P. Lau 《International Journal of Thermophysics》2014,35(3-4):712-724
Accurate temperature measurements in flow lines are critical for many industrial processes. It is normally more a rule than an exception in such applications to obtain water flows with inhomogeneous temperature distributions. In this paper, a number of comparisons were performed between different 100 ohm platinum resistance thermometer (Pt-100) configurations and a new speed-of-sound-based temperature sensor used to measure the average temperature of water flows with inhomogeneous temperature distributions. The aim was to achieve measurement deviations lower than 1 K for the temperature measurement of water flows with inhomogeneous temperature distributions. By using a custom-built flow injector, a water flow with a hot-water layer on top of a cold-water layer was created. The temperature difference between the two layers was up to 32 K. This study shows that the deviations to the temperature reference for the average temperature of four Pt-100s, the multisensor consisting of nine Pt-100s, and the new speed-of-sound sensors are remarkably lower than the deviation for a single Pt-100 under the same conditions. The aim of reaching a deviation lower than 1 K was achieved with the speed-of-sound sensors, the configuration with four Pt-100s, and the multisensor. The promising results from the speed-of sound temperature sensors open the possibility for an integrated flow and temperature sensor. In addition, the immersion depth of a single Pt-100 was also investigated at three different water temperatures. 相似文献
960.
A rational elemental-directed alcohol-thermal route to CdSe nanostructures for thin film solar cells
Yan'ge Zhang Pinjiang Li Woon Ming Lau Yuanhao Gao Junfeng Zi Zhi Zheng 《Materials Chemistry and Physics》2014
We have reported an alcohol-thermal method to in-situ synthesis of Cadmium Selenide (CdSe) nanocrystals/thin films on Cd/indium-doped tin oxide (ITO) substrates through a direct reaction of Se and Cd. In the synthetic system, ligands and surfactants are not introduced, and concentration of reaction precursors is not high, thus not only it is a very economic and environmental-friendly route, but also the CdSe film without any impurities is obtained. The Cd deposited on ITO substrates by magnetron sputtering acted as dual roles: reactant source and hard template for the final product. The microstructure is analyzed by field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). Poly(3-hexylthiophene) (P3HT) is deposited on CdSe film to fabricate a hybrid thin film solar cell device with ITO/CdSe/P3HT/Al structure to demonstrate solar light to electrical energy conversion. 相似文献