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Pre-existing (multiple) shear bands were introduced into the ductile Zr56Co28Al16 and Zr65 Ni10 Cu15 Al10 bulk metallic glasses (BMGs) through the lateral-deformation, respectively. It was found that the pre-exiting shear bands can further enhance the compressive plasticity of ductile BMGs. According to the serration analysis on the plastic deformation of the as-cast and the pre-deformed samples, the serration events in the stress-strain curves during deformation display a self-organized critical ( SOC) behavior. Compared with the as-cast BMGs, a larger power-law scaling exponent calculated based on serrated flow behaviors becomes larger for the pre-deformed BMGs, implying that the shear banding stability of BMGs is effectively enhanced. This should be caused by the pronounced interactions of shear bands during plastic deformation for the pre-deformed BMGs. However, by introducing a large amount of multiple shear bands into the glassy matrix, it also becomes easier for shear bands to propagate along the pre-existing shear bands, leading to a lower cut-off elastic energy density for the pre-deformed BMGs. More multiple shear bands with stronger interactions for the pre-deformed BMGs could provide a larger chance to activate the shear-band cracking but less local elastic energies are remained for the subsequent crack-linking.

The heat transfer performances of evaporators and condensers significantly affect the efficiency of household refrigerators. For enhancing heat transfer of the condensers and evaporators, a novel dual energy storage (DES) refrigerator with both heat storage condenser (HSC) and cold storage evaporator (CSE) is proposed. The performance comparison of three kinds of energy storage refrigerators: HSC refrigerator, CSE refrigerator and DES refrigerator is analyzed by establishing dynamic simulation models. According to the simulation results, the DES refrigerator combines the advantage of HSC refrigerator and CSE refrigerator, it has more balanced operational cycle and higher evaporation pressure and temperature. The DES refrigerator shows a best energy saving performance among the three energy storage refrigerators with largest off-time to on-time ratio of 4.3 and the electrical consumption saving can reach 32%, which is greater than the sum (28%) of the other two kinds of energy storage refrigerators.

A novel multi-objective global optimization method combining refrigerator dynamic model and Genetic algorithm NSGA-II is proposed for increasing overall performance of household refrigerator. A novel refrigerator with heat-storage condensers and an ordinary refrigerator with conventional hot-wall condensers are optimized by the method for multi-objectives of minimizing total cost and energy consumption per 24 h. After the optimization, overall performances of the novel refrigerator and ordinary refrigerator are both increased. Optimized curves on multi-objectives of the novel refrigerator and ordinary refrigerator are obtained and compared with each other. In the optimized curve, for one value of energy consumption per 24 h, a corresponding optimized total cost is acquired. Optimization result of the novel refrigerator is better than that of the ordinary refrigerator. Under the condition of same total cost, energy saving of optimized novel refrigerator compared with optimized ordinary refrigerator is from 20% to 26%. Under the condition of same energy consumption per 24 h, cost saving of optimized novel refrigerator compared with optimized ordinary refrigerator is from $1.8 to $3.4.

In this study, a novel orodispersible film (ODF) containing drug nanoparticles was developed with the goal of transforming drug nanosuspensions into a solid dosage form and enhancing oral bioavailability of drugs with poor water solubility. Nanosuspensions were prepared by high pressure homogenization and then transformed into ODF containing drug nanoparticles by mixing with hydroxypropyl methylcellulose solution containing microcrystalline cellulose, low substituted hydroxypropylcellulose and PEG-400 followed by film casting and drying. Herpetrione, a novel and potent antiviral agent with poor water solubility that extracted from Herpetospermum caudigerum, was chosen as a model drug and studied systematically. The uniformity of dosage units of the preparation was acceptable according to the criteria of Japanese Pharmacopoeia 15. The ODF was disintegrated in water within 30s with reconstituted nanosuspensions particle size of 280 ± 11 nm, which was similar to that of drug nanosuspensions, indicating a good redispersibility of the fast dissolving film. Result of X-ray diffraction showed that HPE in the ODF was in the amorphous state. In the in vitro dissolution test, the ODF containing HPE nanoparticles showed an increased dissolution velocity markedly. In the pharmacokinetics study in rats, compared to HPE coarse suspensions, the ODF containing HPE nanoparticles exhibited significant increase in AUC0-24h, Cmax and decrease in Tmax, MRT. The result revealed that the ODF containing drug nanoparticles may provide a potential opportunity in transforming drug nanosuspensions into a solid dosage form as well as enhancing the dissolution rate and oral bioavailability of poorly water-soluble drugs.

The dynamic model of a novel household refrigerator with SSPCM (shape-stabilized phase change material) heat storage condenser presented in this paper were established and agreed well with the experiment. By simulation, the coefficient of performance is increased about 19% by a continuous heat transfer of condenser due to the latent heat storage of SSPCM, however the energy saving is 12% and offset about 7% by the heat leakage increase because of the SSPCM inside the insulation layer. The effects of ambient temperature, freezer temperature and phase change temperature on the energy saving are analyzed to provide theoretical basis for the optimization design of the refrigerator with SSPCM. It can be concluded that the ambient temperature increasing and the freezer temperature decreasing can increase the energy saving effect, the second phase change temperature region with the peak temperature about 49 °C of SSPCM results in the minimum energy consumption of the novel refrigerator.

A vertical U-tube ground heat exchanger can be utilized to exchange heat with the soil in ground source heat pump systems. The outlet temperature of the working fluid through the U-tube not only accounts for heat transfer capacity of a ground heat exchanger, but also greatly affects the operational efficiency of heat pump units, which is an important characteristic parameter of heat transfer process. It is quantified by defining a thermal effectiveness coefficient. The performance evaluation is performed with a three dimensional numerical model using a finite volume technique. A dynamic simulation was conducted to analyze the thermal effectiveness as a function of soil thermal properties, backfill material properties, separation distance between the two tube legs, borehole depth and flow velocity of the working fluid. The influence of important characteristic parameters on the heat transfer performance of vertical U-tube ground heat exchangers is investigated, which may provide the references for the design of ground source heat pump systems in practice.

In this study, a kind of shape-stabilized phase change material (PCM) was adopted for constructing heat storage condensers. And a novel household refrigerator equipped with the heat storage condensers was setup based on an ordinary double-door three-star compartment refrigerator. The experimental investigation on the characteristics of the novel refrigerator and an ordinary refrigerator was carried out under the ISO standard test conditions. For the novel refrigerator, part of the condensation heat was stored in the shape-stabilized PCM during the on-time and discharged to the environment while the compressor was off. Therefore, the heat dissipation of the novel refrigerator was continuous during a complete cycle (including a successive on-time and off-time period), different from the intermittent heat dissipation of the ordinary setup. Thus, the overall heat-transfer performances of the condensers could be significantly improved, which resulted in a lower condensation temperature, a higher evaporation temperature and a much larger subcooling degree at the condenser outlet. Compared to the ordinary refrigerator, the total cycle time and the ratio of on-time to the total cycle time of the novel refrigerator were much smaller, which led to more frequent starts of the compressor but lower energy consumption. Experiments demonstrated that the novel refrigerator could increase the energy efficiency by about 12% with only little increase of the cost.

A set D of vertices of a graph G = (V,E) is called a dominating set if every vertex of V not in D is adjacent to a vertex of D. In 1996, Reed proved that every graph of order n with minimum degree at least 3 has a dominating set of cardinality at most 3n/8. In this paper we generalize Reed’s result. We show that every graph G of order n with minimum degree at least 2 has a dominating set of cardinality at most (3n+|V 2|)/8, where V 2 denotes the set of vertices of degree 2 in G. As an application of the above result, we show that for k ≥ 1, the k-restricted domination number r k (G, γ) ≤ (3n+5k)/8 for all graphs of order n with minimum degree at least 3.

Let k be a positive integer and D=(V,E) be a minimally k -edge-connected simple digraph. For a vertex x∈V(D) , its outdegree δ + (x) (indegree δ − (x) ) is the number of edges leaving (entering) x . Let u + (D) (resp. u ± (D) and u − (D) ) denote the number of vertices x in D such that δ + (x)=k − (x) (resp. δ + (x)=δ − (x)=k and δ + (x)>k=δ − (x) ). In this paper we prove that u + (D)+2u ± (D)+u − (D)⩾2k+2, which was conjectured by Mader (Combinatorics 2 (1996) 423–449). We also present a lower bound on u + (D)+u ± (D)+u − (D) when |D|⩾4k−1 .

In the present study, a novel hydrogel-grafted fabrics embedding of berberine nanosuspension was developed for the treatment of infected wound. Hydrogel-grafted fabric was prepared by graft copolymerization of N-isopropylacrylamide and alginate using ceric ammonium nitrate as initiator. Berberine nanosuspension was prepared and embedded in the hydrogel-grafted fabrics to achieve sustained drug release. The prepared hydrogel-grafted fabrics embedding of berberine nanosuspension was characterized by FT-IR spectroscopy, scanning electron microscopy, and swelling degree studies. Fourier transform infrared spectroscopy revealed that berberine was embedded into the matrix of hydrogel-grafted fabrics, rather than on the surface. Scanning electron microscopy showed that a thin hydrogel layer was formed on the surface of nonwoven fibers. The swelling study showed that hydrogel-grafted fabric had water absorbing characteristic with reversible temperature sensitivity. The drug release study demonstrated that hydrogel-grafted fabrics can be used as a sustained drug delivery system of hydrophobic compounds. The berberine nanosuspension embedded hydrogel-grafted fabric was further investigated in an animal infected wound model and was found to be a very promising wound healing dressing for the treatment and healing of infected wounds.

It's natural and direct to identify the structural stiffness based on the measurement of static displacement; In addition, considering that the lower frequencies of structures can be tested with high precision and can reflect the global dynamic properties of structures, static displacements at partial nodes and several low frequencies were used to constitute the input parameter vectors for neural networks. A damage numerical verification on an arch bridge model was carried out using a radical basis function (RBF) network. Identification results indicate that the neural network has an excellence capability to identify the location and extent of structural damage with the limited noises and incomplete measured data.

The fusion protein of Humanized mouse anti-human fibrin ScFv and the low molecular weight urokinase (IIn-UK) contained seven disulfide bonds and formed inclusion body while expressing in normal E. coli strain. By coexpressing DsbC and using the special E. coli strain Origami(DE3) which was trxB/gor double mutant, the fusion protein IIn-UK was functionally expressed in the cytoplasm of E. coli. The expressed fusion protein in the soluble fraction was purified by using affinity chromatography specific against urokinase. The purified fusion protein could combine the thrombus in vitro, and the specific activity of urokinase reached 80,000 IU/mg fusion protein. The result showed that the fusion protein retained the activity of two moieties, and this study laid a foundation for further research of targeting thrombolytic agent.