Showing papers by "Harbin Institute of Technology published in 2006"
TL;DR: Co3O4/BiVO4 composite photocatalyst with a p-n heterojunction semiconductor structure has been synthesized by the impregnation method and exhibits enhanced photocatalytic activity for phenol degradation under visible light irradiation.
Abstract: Co3O4/BiVO4 composite photocatalyst with a p−n heterojunction semiconductor structure has been synthesized by the impregnation method. The physical and photophysical properties of the composite photocatalyst have been characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transimission electron microscopy (TEM), BET surface area, and UV−visible diffuse reflectance spectra. Co is present as p-type Co3O4 and disperses on the surface of n-type BiVO4 to constitute a heterojunction composite. The photocatalyst exhibits enhanced photocatalytic activity for phenol degradation under visible light irradiation. The highest efficiency is observed when calcined at 300 °C with 0.8 wt % cobalt content. On the basis of the calculated energy band positions and PL spectra, the mechanism of enhanced photocatalytic activity has been discussed.
820 citations
TL;DR: In this paper, a polyvinylidene fluoride (PVDF) ultrafiltration membrane was modified by dispersing nano-sized alumina (Al2O3) particles uniformly in a PVDF solution (19% polymer weight).
541 citations
TL;DR: In this paper, the abrasion resistance of concrete containing nano-particles for pavement is experimentally studied, and the relationship between the indices of sub-packetization and compressive strength of concrete is obtained.
479 citations
TL;DR: Partial nitrification to nitrite was reported to be technically feasible and economically favorable, especially when wastewater with high ammonium concentrations or low C/N ratios is treated.
Abstract: Presently, the wastewater treatment practices can be significantly improved through the introduction of new microbial treatment technologies. To meet increasingly stringent discharge standards, new applications and control strategies for the sustainable removal of ammonium from wastewater have to be implemented. Partial nitrification to nitrite was reported to be technically feasible and economically favorable, especially when wastewater with high ammonium concentrations or low C/N ratios is treated. For successful implementation of the technology, the critical point is how to maintain partial nitrification of ammonium to nitrite. Partial nitrification can be obtained by selectively inhibiting nitrite oxidizing bacteria through appropriate regulation of the system's DO concentration, microbial SRT, pH, temperature, substrate concentration and load, operational and aeration pattern, and inhibitor. The review addressed the microbiology, its consequences for their application, the current status regarding application, and the future developments.
433 citations
TL;DR: In this article, a comparison of the performance and morphology was carried out between neat PVDF membrane and PVDF composite membranes with nanosized TiO2 particles of different size, and the results of permeability and instrumental analysis illustrated that nanometer size obviously affected the performance of the PVDF membranes.
429 citations
TL;DR: An information measure is proposed to computing discernibility power of a crisp equivalence relation or a fuzzy one, which is the key concept in classical rough set model and fuzzy-rough set model, and a general definition of significance of nominal, numeric and fuzzy attributes is presented.
395 citations
TL;DR: In this paper, a series of [0/90]3s laminates with varying void contents were fabricated and a characterization of void distribution, size, and shape within the Laminates was obtained using ultrasonic c-scan and optical metallography techniques.
387 citations
TL;DR: In this paper, the durability of carbon black supported Pt and multiwalled carbon nanotubes supported Pt (Pt/CNTs) catalysts for potential application in polymer electrolyte membrane fuel cells is investigated using an accelerated durability test.
Abstract: The durability of carbon black supported Pt (Pt/C) and multiwalled carbon nanotubes supported Pt (Pt/CNTs) catalysts for potential application in polymer electrolyte membrane fuel cells are investigated using an accelerated durability test. The electrochemical surface area of Pt/C degrades by 49.8% during the 192-h test time, compared with 26.1% for Pt/CNTs, which is due to Pt particle growth and Pt loss from the support in the form of Pt ions and Pt particles. Transmission electron microscopy and X-ray diffraction analysis show that Pt particles in Pt/CNTs present higher sintering resistance. X-ray photoelectron spectroscopy characterization indicates that CNTs in Pt/CNTs are more resistant to electrochemical oxidation than carbon black in Pt/C. It can be concluded that Pt/CNTs are more stable under electrochemical operation, which can be attributed to specific interaction between Pt and the support and the higher resistance of the support to electrochemical oxidation.
385 citations
TL;DR: A pilot-scale study of bio-hydrogen production was performed in a continuous flow anaerobic fermentation reactor (with an available volume of 1.48 m3) for over 200 days as mentioned in this paper.
377 citations
TL;DR: In this article, the authors used permanganate as the cathodic electron acceptor for a two-chamber microbial fuel cell (MFC) and achieved a power density of 115.60 mWmWm−2.
339 citations
TL;DR: In this article, the authors presented several delay-dependent conditions for a general complex dynamical network model with coupling delays, which guarantee the synchronized states to be asymptotically stable.
TL;DR: In this paper, the resistance to electrochemical oxidation of carbon black (Vulcan XC-72) and chemical vapor deposited multiwalled carbon nanotubes (CVD-MWNTs), both widely used as catalyst supports for low temperature fuel cells, was investigated with potentiostatic oxidation in 0.5 −1 H2SO4.
01 Jan 2006
TL;DR: The most frequently used ways of dealing with parameter uncertainties, including polytopic and norm-bounded characterizations, have been taken into consideration, with convex optimization problems obtained for the design of desired robust energy-to-peak filters.
TL;DR: In these protocols, the secret transmitting order of particles ensures the security of communication, and no secret messages are leaked even if the communication is interrupted for security.
Abstract: We propose the schemes of quantum secure direct communication based on a secret transmitting order of particles. In these protocols, the secret transmitting order of particles ensures the security of communication, and no secret messages are leaked even if the communication is interrupted for security. This strategy of security for communication is also generalized to a quantum dialogue. It not only ensures the unconditional security but also improves the efficiency of communication.
TL;DR: A theory about fuzzy probabilistic approximation spaces is proposed in this paper, which combines three types of uncertainty: probability, fuzziness, and roughness into a rough set model.
Abstract: Rough set theory has proven to be an efficient tool for modeling and reasoning with uncertainty information. By introducing probability into fuzzy approximation space, a theory about fuzzy probabilistic approximation spaces is proposed in this paper, which combines three types of uncertainty: probability, fuzziness, and roughness into a rough set model. We introduce Shannon's entropy to measure information quantity implied in a Pawlak's approximation space, and then present a novel representation of Shannon's entropy with a relation matrix. Based on the modified formulas, some generalizations of the entropy are proposed to calculate the information in a fuzzy approximation space and a fuzzy probabilistic approximation space, respectively. As a result, uniform representations of approximation spaces and their information measures are formed with this work
TL;DR: In this paper, a linear relationship between the fractional change in resistivity and compressive strain was observed for cement-based composites containing a large amount of carbon black (CB), suggesting that this kind of composite was a promising candidate for strain sensors used in concrete structures.
Abstract: This paper investigates the strain sensing properties of carbon black (CB)-filled cement-based composites which were prepared with 120 nm CB. A linear relationship between the fractional change in resistivity and compressive strain was observed for cement-based composites containing a large amount of CB, suggesting that this kind of composite was a promising candidate for strain sensors used in concrete structures. Tunneling effect theory and percolation theory are employed to interpret the conductivity and electromechanical properties of CB-filled cement-based composites.
TL;DR: In this paper, a conductive sulfur-containing nanocomposite cathode material was synthesized by heating the mixture of sublimed sulfur and multi-walled carbon nanotubes (MWNTs) in certain conditions.
TL;DR: In this article, a load-dependent controller design approach was proposed to solve the problem of multi-objective control for vehicle active suspension systems by using linear matrix inequalities, where the vehicle body mass resides in an interval and can be measured online.
TL;DR: A tubular UF module equipped with polyvinylidene fluoride membranes modified by inorganic nano-sized alumina particles was used to purify oily wastewater from an oil field.
TL;DR: In this paper, conductivity relaxation behaviors of cathode materials were investigated at temperature 400-550 degrees C. Generally, Ba0.2O3-delta and Ba 0.5Sr0.5Co0.8Fe0.
Abstract: BaxSr1-xCo0.8Fe0.2O3-delta (0.3 0.5 compositions. Furthermore, conductivity relaxation behaviors were also investigated at temperature 400-550 degrees C. Generally, Ba0.4Sr0.6Co0.8Fe0.2O3-delta and Ba0.5Sr0.5Co0.8Fe0.2O3-delta are potential cathode materials. (c) 2005 Elsevier Ltd. All rights reserved.
TL;DR: It is demonstrated that myostatin down-regulates Cdk4 activity via promotion of cyclin D1 degradation, uncovering a novel role for mystatin in the regulation of cell growth and cell death in concert with IGF-1.
TL;DR: In this article, the microstructure, phase composition and elemental distribution of ceramic coatings were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDX).
TL;DR: In this article, the authors used elastic beam theory to analyze the theoretical displacement amplification ratio of a bridge-type flexure hinge, and they showed that increasing the amplification ratio by decreasing the thickness of the flexure pivots led to a decrease in the mode shape frequency.
Abstract: The bridge-type flexure hinge is a classic displacement amplification mechanism The existing models of theoretic displacement amplification ratio of bridge-type flexure hinges are not perfect This makes it very difficult to design and manufacture a satisfactory structure using these models Kinematic theory was used to analyze the ideal displacement amplification ratio of a bridge-type flexure hinge in this paper, and the flexure hinge was regarded as a pure multi-rigid body with ideal pivots Elastic beam theory was used to analyze the theoretic displacement amplification ratio when considering the translational and rotational stiffness of the flexure pivots The model of theoretic displacement amplification ratio explains why the bridge-type displacement amplification mechanism has an amplification ratio extremum and where the threshold is The finite element method was used for comparison with the mathematical model, and similar results were obtained Finally, the finite element method was used to analyze the shape mode of the structure The result showed that increasing the amplification ratio by decreasing the thickness of the flexure pivots led to a decrease in the mode shape frequency of the bridge-type structure Thus, redesigning of the structure was needed to solve the problem
TL;DR: In this article, an electrospinning method was used to prepare electrospun PVDF-based membranes (EPMs) for battery separators applications, and the morphology of the EPMs was investigated by scanning electron microscopy (SEM).
Abstract: An electrospinning method was used to prepare electrospun PVDF-based membranes (EPMs) for battery separators applications. The morphology of the EPMs was investigated by scanning electron microscopy (SEM). The relations between applied voltage and average fiber diameter (AFD) under certain electrospinning conditions were discussed. The thermal properties and crystal structure of the EPMs also were investigated by differential scanning calorimetry (DSC), and wide-angle X-ray diffraction (WAXD). Due to soften PVDF fibers in high temperature, the thermal treated EPMs can form an interconnected web structure, which greatly improves physical properties. Compared with Celgard™ 2400 (PP separator), the cell with EPM shows better cycling ability of CV and charge–discharge performance with little capacity loss after 50 cycles at C/2 rate.
TL;DR: In this article, the photocatalytic activities of chromium-doped SrTiO3 powders were investigated under UV and visible light conditions, and the results of density functional theory (DFT) calculation illuminate that the visible-light absorption bands in the SrTi1−xCrxO3 catalyst are attributed to the band transition from the Cr 3d to the Cr3d+Ti 3d hybrid orbital.
TL;DR: In this article, a new organic-inorganic hybrid based on PS/TiO 2 hybrid membranes were prepared by sol-gel and phase inversion process, which were characterized in terms of morphology, structure, hydrophlicity, UF performance and thermal stability.
TL;DR: Two novel gene selection methods are proposed in this paper, which are not affected by the unbalanced sample class sizes and do not assume any explicit statistical model on the gene expression values, and give more accurate classification results when the sampleclass sizes in the training dataset are unbalanced.
Abstract: Microarray data analysis is notorious for involving a huge number of genes compared to a relatively small number of samples. Gene selection is to detect the most significantly differentially expressed genes under different conditions, and it has been a central research focus. In general, a better gene selection method can improve the performance of classification significantly. One of the difficulties in gene selection is that the numbers of samples under different conditions vary a lot. Two novel gene selection methods are proposed in this paper, which are not affected by the unbalanced sample class sizes and do not assume any explicit statistical model on the gene expression values. They were evaluated on eight publicly available microarray datasets, using leave-one-out cross-validation and 5-fold cross-validation. The performance is measured by the classification accuracies using the top ranked genes based on the training datasets. The experimental results showed that the proposed gene selection methods are efficient, effective, and robust in identifying differentially expressed genes. Adopting the existing SVM-based and KNN-based classifiers, the selected genes by our proposed methods in general give more accurate classification results, typically when the sample class sizes in the training dataset are unbalanced.
TL;DR: Extracellular polymeric substances were produced mainly in the exponential phase, and served as carbon and energy source in starvation phase during granulation process, thus regulating the growth of bacteria in the interior and exterior of granule, and maintaining the integrality of granules.