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51.
Herein, the generation of gold, silver, and silver–gold (Ag–Au) bimetallic nanoparticles was carried out in collagen (gelatin)
solution. It first showed that the major ingredient in gelatin polypeptide, glutamic acid, acted as reducing agent to biomimetically
synthesize noble metal nanoparticles at 80°C. The size of nanoparticles can be controlled not only by the mass ratio of gelatin
to gold ion but also by pH of gelatin solution. Interaction between noble-metal nanoparticles and polypeptide has been investigated
by TEM, UV–visible, fluorescence spectroscopy, and HNMR. This study testified that the degradation of gelatin protein could
not alter the morphology of nanoparticles, but it made nanoparticles aggregated clusters array (opposing three-dimensional
α-helix folding structure) into isolated nanoparticles stabilized by gelatin residues. This is a promising merit of gelatin
to apply in the synthesis of nanoparticles. Therefore, gelatin protein is an excellent template for biomimetic synthesis of
noble metal/bimetallic nanoparticle growth to form nanometer-sized device. 相似文献
52.
Event sequences and time series are widely recorded in many application domains; examples are stock market prices, electronic health records, server operation and performance logs. Common goals for recording are monitoring, root cause analysis and predictive analytics. Current analysis methods generally focus on the exploration of either event sequences or time series. However, deeper insights are gained by combining both. We present a visual analytics approach where users can explore both time series and event data simultaneously, combining visualization, automated methods and human interaction. We enable users to iteratively refine the visualization. Correlations between event sequences and time series can be found by means of an interactive algorithm, which also computes the presence of monotonic effects. We illustrate the effectiveness of our method by applying it to real world and synthetic data sets. 相似文献
53.
This study was conducted to investigate the virtual display effects on direct interaction performance metrics such as accuracy, task completion time, and comfort. Eighteen participants performed tapping (pointing) tasks in the coronal plane by directly reaching for tapping targets at three egocentric distance levels, with three indices of difficulty at each egocentric distance. The position data and severity of cybersickness symptoms were collected with a motion system and a symptom questionnaire, respectively. The results indicated that accuracy was higher with the stereoscopic widescreen display than with the head mounted display. However, no significant differences in task completion time, throughput, and cybersickness were observed between the two VR displays. In addition, increasing the egocentric distance improved accuracy and lengthened the task completion time, whereas increasing the task difficulty lengthened the task completion time but did not affect the accuracy. The findings are important and informative for users in choosing between the two virtual reality displays. Generally, the stereoscopic widescreen display can be recommended for tasks requiring high egocentric distance accuracy in the coronal plane. Furthermore, developers may refer to these findings in designing interfaces that allow a more natural way of interaction for users. 相似文献
54.
Vilius Poderys Marija Matulionyte Algirdas Selskis Ricardas Rotomskis 《Nanoscale research letters》2011,6(1):9-6
Semiconductor nanoparticles (quantum dots) are promising fluorescent markers, but it is very little known about interaction of quantum dots with biological molecules. In this study, interaction of CdTe quantum dots coated with thioglycolic acid (TGA) with bovine serum albumin was investigated. Steady state spectroscopy, atomic force microscopy, electron microscopy and dynamic light scattering methods were used. It was explored how bovine serum albumin affects stability and spectral properties of quantum dots in aqueous media. CdTe–TGA quantum dots in aqueous solution appeared to be not stable and precipitated. Interaction with bovine serum albumin significantly enhanced stability and photoluminescence quantum yield of quantum dots and prevented quantum dots from aggregating. 相似文献
55.
Chinh Nguyen-Huy Nayoung Kim Thuy-Duong Nguyen-Phan Ik-Keun Yoo Eun Woo Shin 《Nanoscale research letters》2014,9(1):462
Nanocomposite materials containing graphene oxide have attracted tremendous interest as catalysts and adsorbents for water purification. In this study, mesoporous titanosilicate/reduced graphene oxide composite materials with different Ti contents were employed as adsorbents for removing bisphenol A (BPA) from water systems. The adsorptive interaction between BPA and adsorption sites on the composite materials was investigated by Fourier transform infrared (FT-IR) and Raman spectroscopy. Adsorption capacities of BPA at equilibrium, q
e
(mg/g), decreased with increasing Ti contents, proportional to the surface area of the composite materials. FT-IR observations for fresh and spent adsorbents indicated that BPA adsorbed onto the composite materials by the electrostatic interaction between OH functional groups contained in BPA and on the adsorbents. The electrostatic adsorption sites on the adsorbents were categorized into three hydroxyl groups: Si-OH, Ti-OH, and graphene-OH. In Raman spectra, the intensity ratios of D to G band were decreased after the adsorption of BPA, implying adsorptive interaction of benzene rings of BPA with the sp2 hybrid structure of the reduced graphene oxide. 相似文献
56.
《Journal of the European Ceramic Society》2014,34(12):3061-3068
In order to reduce the interaction between the Ti alloys and ceramic shell during the casting, materials with high thermal and chemical inertness were used in investment casting. An investigation was undertaken to analyze the influence of the change of binder systems on the slurries, facecoats and the thermo-chemical properties of the facecoat systems using an Y2O3–ZrO2 filler material. The results showed that, using alumina-sol as the binder in the slurry gave the longest life of around three days followed by that using the commercially available zirconia-sol at around 6 h, and the yttria sol based slurry giving a shortest life of around 1.5 h. Meanwhile using the alumina-sol can also enhance the facecoat sintering properties. There was no obvious evidence observed that the change of the binder system influenced the facecoat chemical inertness. 相似文献
57.
Micellar and Interfacial Behavior of Mixed Systems Containing Glycoside‐Based Surfactant and Cationic Didecyldimethylammonium Chloride 下载免费PDF全文
The behavior of binary mixtures of glycoside‐based surfactants in combination with didecyldimethylammonium chloride (DDAC) has been studied using surface tension measurements. The three glycoside‐based surfactants are nonionic decyl glycoside (APG), nonionic dodecyl ethoxy glycoside (AEG) and anionic disodium dodecyl ethoxy glycoside citrate (AEG‐EC). Lower critical micelle concentrations (CMC) and minimum molecular area (Amin) values were obtained for all the mixed systems. The pC20 values of APG/DDAC and AEG‐EC/DDAC mixtures are larger than pure surfactants, while the values of AEG/DDAC are between those of AEG and DDAC. Interactions between the monomers have also been investigated by determining the interaction parameters. Negative βm and βs values indicate synergistic effects in both the mixed micelle and monolayer formation. For different mixed systems, interaction in the mixed micelle formation becomes stronger in the order: AEG/DDAC < AEG‐EC/DDAC < APG/DDAC. The degree of synergism in the mixed monolayer formation follows the order: AEG/DDAC < APG/DDAC < AEG‐EC/DDAC. 相似文献
58.
《Applied Catalysis A: General》1997,150(2):197-220
The effect of high temperature reduction (HTR) in hydrogen (up to 1180 K) on the microstructure of 9 wt.-% Pd/CeO2 catalyst was studied by HRTEM and XRD methods. Reduction of the catalyst at or above 973 K caused severe recrystallization of CeO2 and Pd with simultaneous strong interaction between the two components appearing as three phenomena: epitaxial growth of small Pd particles on CeO2 (most frequently with [111]Pd[111]CeO2); decoration of large Pd particles with ordered CeO2 overlayer and expansion of the lattice parameter of Pd (by 2.1%). The origin of the Pd lattice expansion is discussed and diffusion of Ce species into the Pd lattice seems to be the most probable one. HTR caused also phase transformations in the ceria support. At 973 K and 1100 K, whole CeO2 was transformed into oxygen deficient CeOx phase exhibiting the same or similar structure but with expanded lattice parameter (by 2.8%). At 1180 K most ceria was transformed into hexagonal A-Ce23. The CeOx phase appeared to be stable in hydrogen and in vacuum at room temperature, but upon exposure to air at room temperature it rapidly reoxidised to CeO2. Ce2O3 also reoxidised to CeO2 but much slower. Another consequence of HTR at or above 773 K was formation of pits in CeO2 crystallites, mainly on (112)-type crystal faces. The pits (1–10 nm) exhibited well defined walls parallel to CeO2 lattice fringes and they could possibly constitute nucleation sites for strongly bonded, epitaxial oriented Pd particles. 相似文献
59.
Dong-Pyo Hong Ryoichi Kuboi Isao Komasawa 《Korean Journal of Chemical Engineering》1997,14(5):334-340
Specific interfacial properties, which affect protein extraction in AOT and AOT-lecithin reverse micellar systems (RVMS),
have been studied by using their percolation processes. Solubilization of proteins or synthetic polymers into RVMS by the
injection method and its effect on the percolation processes could be easily evaluated by the measurement of electrical conductivity.
The percolation process is found to be a sensitive and convenient measure of micro-interface of RVMS solubilizing various
polymers or proteins, which clearly reflects the polymer(protein)-micellar and micellar-micellar interactions. The stability
of RVMS or micellar-micellar interaction was dependent on the kinds, concentration and molecular weight of solubilized polymers.
The value of p, defined as the variation of percolation threshold with the concentration of solubilized polymers, can be utilized
to evaluate the stability of RVMS solubilizing polymers or micellar-micellar interactions. The values of Β are affected by
the hydrophobicity, molecular weight and absolute value of the net charge of the polymers solubilized into the AOT reverse
micelles, which were evaluated by using Aqueous Two-Phase Systems (ATPS). 相似文献
60.