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The effect of Sc-microalloying and Y2O3 nano-particles on the microstructure and mechanical properties of as-cast Al-5.5Si alloy is studied by means of optical microscopy, transmission electron microscopy, hardness test and tensile test. The influence of annealing treatment on the microstructure and properties of the Al-Si alloys is also investigated as well. The results show that the addition of Sc and Y2O3 nano-particles could significantly improve the mechanical property of the Al-Si alloy. The ultimate tensile strength and yield strength of Al-Si-Sc/Y2O3 alloy are improved by around 45 and 71%, respectively, when compared to that of the Al-Si alloy. The effect of the nanosized particles (precipitated and added) on strengthening and deformation of Al-Si alloy is analyzed and discussed in detail. The results of annealing treatment indicate that the change in mechanical property of the Al-Si-Sc alloy during annealing treatment is mainly associated with the precipitation of the secondary Si phase.

This study attempts to improve the vibration isolation performance of a vehicle suspension system with a magnetorheological damper (MRD) under complex driving conditions. Structure parameter uncertainty, disturbance of the driving process, and response time delay of MRD are all addressed. Firstly, experiments of MRD were carried out in a damping force testing machine to identify the parameters of the MRD adjustable Sigmoid model by the Levenberg-Marquardt optimization algorithm. Then, the parameter identification is verified by comparing experimental and simulation data. Secondly, the state space equations of the suspension system are derived by Newton’s second law. The transfer function from the bounded disturbance input to the control output is obtained based on H∞ control theory. To make the Infinite norm of the system transfer function less than a certain value, three control strategies are proposed: variable structure control (VSC), disturbance rejection control (DRC), and delay tolerance control (DTC). Thirdly, considering these issues together to weaken the effect of disturbances on vehicle driving conditions, a fuzzy cooperative control (FCC) strategy is proposed based on the linear matrix inequality (LMI) theory. Simulation results demonstrate that FCC semi-active vehicle suspension systems conduct effective vibration isolation performance while responding to multiple external disturbances.

Not only economic pressures but also environmental demands and regulatory requirements bring a great interest in improving marine propeller efficiency. The design of a bio-inspired marine propeller...

The tip vortex cavitation (TVC) is an issue of increasing interest, because the TVC plays an important role in propeller radiated noise and cavitation erosion. The marine propeller with winglets, which is inspired by the winglets of airfoil, is numerically investigated in the present paper. The blade tip of newly designed propeller tilts toward the pressure side. The difference between six propellers is the change of the rake angle at r/R = 1.0. The pressure coefficient, TVC, axial velocity field and helicity are analyzed. The numerical results show that the winglets of newly designed propeller scarcely affect the efficiency of propeller. The thrust coefficient gradually decreases with the increase in rake angle. As for the suction side, the pressure coefficient (Cp) of winglets propellers is higher than the conventional propeller in general. In addition, the winglets are beneficial to generate less cavitation behavior when the rake angle is small. However, as the rake angle is further increased, the cavitation behavior of winglets propeller is also increased, even larger than the conventional propeller. Therefore, it can be deduced that the winglets can be used to effectively improve the TVC characteristics to some extent.

ZnO:Tb nanoparticles are prepared by a solvothermal method with the diameter of approximately 18–100 nm. At appropriate doping concentration, the lattice expansion occurs. With the increase in the doping ratio of Tb/Zn from 0 to 0.03, ZnO lattice first contracts slightly, then expands, and finally, contracts again. Tb3+ element is found to enter the ZnO lattice and replace Zn2+. Some crystal defects are generated in the host lattice for doped samples such as Zni and VO. By carefully examining the excitation and emission spectra, both VO and Zni are found to be involved in the energy transfer process. This is different from ZnO:Eu for which negative charge Oi defects are identified to play an important medium of energy transfer from ZnO host to Eu3+. It also supports another charge compensation mechanism. The energy transfer mechanism helps to theoretically explain and promote strong green luminescence of Tb3+ and improves the luminescence intensity of the RE-doped ZnO nanomaterial. It is very valuable for potential applications in bioimaging, photoluminescence, optoelectronics, and photocatalysis.

The generation of tip vortex cavitation (TVC) is a common phenomenon in marine propellers. Therefore, it is important to find a way for the effective suppression of TVC. Based on the enlightenment of bionics, a propeller with winglets was numerically investigated by using a large eddy simulation (LES) model and the commercial software STAR-CCM+. Various variables, such as mesh size, number of prism layers, vapor properties and time step, were analyzed using the benchmark MAU5-80 propeller. The open water characteristics calculated for the benchmark propeller were compared with experimental data. The meshes in the region of the tip vortex wake were refined. The power spectral density (PSD) of the thrust coefficient and axial velocity were investigated. The comparison of TVC between the benchmark propeller and the propeller with winglets was studied with the Q-criterion, helicity and volume fraction of the vapor. The strength of the tip vortex wake is weakened by winglets, therefore, the presence of winglets leads to a reduction in vapor volume, which in turn alleviates TVC.

The duck's webbed feet are observed by using electron microscopy, and observations indicate that the edges of the webbed feet are the shape of protuberances. Therefore, the rudder with leading-edge protuberances is numerically studied in the present investigation. The rudder has a sinusoidal leading-edge profile along the spanwise direction. The hydrodynamic performance of rudder is analyzed under the influence of leading-edge protuberances. The present investigations are carried out at Re = 3.2 × 105 and 8 × 105. In the case of Re = 3.2 × 105, the curves of lift coefficient illustrate that the protuberant leading-edge scarcely affects the lift coefficient of bionic rudder. However, the drag coefficient of the bionic rudder is markedly lower than that of the unmodified rudder. Therefore, the lift-to-drag ratio of the bionic rudder is obviously higher than the unmodified rudder. In another case of Re = 8 × 105, the advantageous behavior of the bionic rudder with leading-edge protuberances is mainly performed in the post-stall regime. The flow mechanism of the significantly increased efficiency by the protuberant leading-edge is explored. It is obvious that the pairs of counter-rotating vortices are presented over the suction surface of bionic rudder, and therefore, the flow is more likely to adhere to the suction surface of bionic rudder.

The marine rudder with leading-edge protuberances is numerically investigated by SST k-ω turbulence model in present investigations. The newly designed rudder has a sinusoidal leading-edge profile along the spanwise direction. The numerical results show that the newly designed rudder helps to improve the lift coefficient of the rudder. The efficiency of the rudder is improved by adopting the leading-edge protuberances. The results are analyzed by means of streamlines and pressure coefficient. The leading-edge protuberances can delay or overcome the stall. The effect of leading-edge protuberances on the pressure coefficient of pressure surface is very small. However, the pressure coefficient of the suction surface is changed in the vicinity of leading-edge.

Ordered mesoporous g-C3N4 (ompg-C3N4) was synthesized in an aqueous solution via a green cosolvent-free nanocasting route by replacing the extremely virulent cyanamide with the environment-friendly starting material dicyandiamide (DCDA) for the first time. The well-defined cashew-shaped ompg-C3N4 was obtained when the weight ratio of DCDA to mesoporous silica SBA-15 was controlled at 2 : 1 in the nanocasting process. The excellent photocatalytic performance towards the degradation of methyl orange (MO), a hazardous dye, was evaluated under visible light irradiation and the degradation rate constant of ompg-C3N4 was determined to be 30 times as high as that of bulk g-C3N4. The significantly enhanced photodegradation activity of ompg-C3N4 is mainly attributed to the ordered mesopores inside individual particles, which accelerate the adsorption of the dye onto the catalyst surface and shorten the diffusion path of free carriers from the bulk phase to the surface, thereby enhancing the separation efficiency of photogenerated electrons and holes. In addition, a possible MO photodegradation mechanism was proposed based on the results of the control experiments in the presence and absence of scavengers.

In this paper, the Mixture multiphase flow model and the Schnerr-Sauer cavitation model are used to simulate the tip vortex cavitation of the propeller and then to predict the sound pressure level of the propeller. The structured and unstructured grids are adopted in stationary domain and rotating domain, respectively. The moving reference frame model is used in the rotating domain. The open water characteristics of the propeller are calculated by the SST k-ω turbulence model and the isosurface of vorticity magnitude is clearly presented. The results of the calculation are compared with the non-cavitating condition. It shows that the efficiency of the propeller is reduced when the tip vortex cavitation appears. The tip vortex cavitation will lead to increases both in the overall sound pressure in time histories and in the sound pressure level in the frequency domain.

First, polyaniline–graphene oxide (GO–PANI) nanocomposites were prepared by the in situ polymerization of aniline in the presence of graphene oxide (GO). Next, the GO–PANI nanocomposites were reduced to polyaniline–graphene (G–PANI) nanocomposites by a green electrochemical reduction method. Finally, a thin layer of nearly monodispersed Au nanoparticles with a uniform size (∼12 nm) was coated on the surface of the G–PANI nanocomposites. Moreover, the as-prepared Au–polyaniline–graphene (Au–G–PANI) nanocomposites can be used as a sensing electrode material for the electrochemical detection of nitrite (NO2−). Compared with other common modified electrodes, the Au–G–PANI/GCE shows an obvious oxidation peak of NO2− with a larger peak current, and gives a wider linear range from 0.1 to 200 μmol L−1, with a detection limit of 0.01 μmol L−1 (S/N = 3). Besides, the oxidation process of NO2− on the Au–G–PANI/GCE is proven to be a surface-controlled process involving the transfer of two electrons. The present study widens the applications of graphene-based nanocomposite materials in the electrochemical detection of environmental pollutants.

The development of nanostructured conducting polymers based materials for electrochemical applications has attracted intense attention due to their environmental stability, unique reversible redox properties, abundant electron active sites, rapid electron transfer and tunable conductivity. Here, a phytic acid doped polyaniline nanofibers based nanocomposite was synthesized using a simple and green method, the properties of the resulting nanomaterial was characterized by electrochemical impedance spectroscopy (EIS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). A glassy carbon electrode modified by the nanocomposite was evaluated as a new platform for the simultaneous detection of trace amounts of Cd2+ and Pb2+ using differential pulse anodic stripping voltammetry (DPASV). The synergistic contribution from PANI nanofibers and phytic acid enhances the accumulation efficiency and the charge transfer rate of metal ions during the DPASV analysis. Under the optimal conditions, good linear relationships were obtained for Cd2+ in a range of 0.05–60 μg L−1, with the detection limit (S/N = 3) of 0.02 μg L−1, and for Pb2+ in a range of 0.1–60 μg L−1, with the detection limit (S/N = 3) of 0.05 μg L−1. The new electrode was successfully applied to real water samples for simultaneous detection of Cd2+ and Pb2+ with good recovery rates. Therefore, the new electrode material may be a capable candidate for the detection of trace levels of heavy metal ions.

B-lymphocyte stimulator (BAFF) is a recently recognized member of the tumor necrosis factor ligand family (TNF) and a potent cell-survival factor expressed in many hematopoietic cells. BAFF regulates B-cell survival, differentiation, and proliferation by binding to three TNF receptors: TACI, BCMA, and BAFF-R. The mechanism involved in BAFF-R gene expression and regulation remains elusive. In this study, we examined BAFF-R gene expression, function, and regulation in multiple myeloma (KM3) cells. It was found that BAFF-BAFF-R induced cell survival by activating NF-κB1 pathway and NF-κB2 pathway. It was also found that NF-κB was an important transcription factor involved in regulating BAFF-R expression through one NF-κB binding site in the BAFF-R promoter, suggesting that inhibiting NF-κB could decrease the expression of BAFF-R mRNA and protein, and promote activity of BAFF-R gene. Our findings indicate that both NF-κB pathways are involved in the regulation of BAFF-R gene and the NF-κB-binding site of BAFF-R may be a new therapeutic target in this disease.

Poly(4-aminobenzoic acid)/electrochemically reduced graphene oxide composite film modified glassy carbon electrodes (4-ABA/ERGO/GCEs) were fabricated by a two-step electrochemical method. The electrochemical behavior of acetaminophen at the modified electrode was investigated by means of cyclic voltammetry. The results indicated that 4-ABA/ERGO composite films possessed excellent electrocatalytic activity towards the oxidation of acetaminophen. The electrochemical reaction of acetaminophen at 4-ABA/ERGO/GCE is proved to be a surface-controlled process involving the same number of protons and electrons. The voltammetric determination of acetaminophen performed with the 4-ABA/ERGO modified electrode presents a good linearity in the range of 0.1-65 μM with a low detection limit of 0.01 μM (S/N=3). In the case of using the 4-ABA/ERGO/GCE, acetaminophen and dopamine can be simultaneously determined without mutual interference. Furthermore, the 4-ABA/ERGO/GCE has good reproducibility and stability, and can be used to determine acetaminophen in tablets.

Cancerous inhibitor of protein phosphatase 2A (CIP2A) has been identified as an oncoprotein that is able to promote the proliferation of cancer cells. The role of CIP2A in the anticancer activity of bortezomib in colon cancer remains to be elucidated. In the present study, the antitumor effect of bortezomib was investigated and the role of CIP2A in determining the effect on colon cancer cells was identified. In the present study, bortezomib demonstrated an antitumor effect, as observed by WST‑1 assay and flow cytometry. In addition, the mRNA and protein level of CIP2A was inhibited in a dose‑dependent manner by bortezomib with quantitative PCR (qPCR) and western blotting. Furthermore, the inhibition of CIP2A with small interfering RNA by treatment with bortezomib inhibited proliferation, increased apoptosis and attenuated the invasion of the cells. Finally, the in vivo data demonstrated that bortezomib was able to decrease the growth of tumors, and that CIP2A was downregulated in the LoVo tumors treated with bortezomib. Therefore, CIP2A was shown to be important in the bortezomib‑induced inhibitory effect on colon cancer.

A novel electrochemical sensor for the detection of glucose was constructed based on the use of Co3O4/PbO2 core-shell nanorod arrays as electrocatalysts. In this paper the Co3O4/PbO2 core-shell nanorod arrays grow directly on a flexible carbon cloth substrate by the combination of hydrothermal synthesis and electrochemical deposition methods. The as-prepared hierarchical nanocomposites show the structural characteristics of nanowire core and nanoparticle shell. The carbon cloth-supported Co3O4/PbO2 nanorod array electrode exhibits higher sensitivity (460.3 μA mM(-1)cm(-2) in the range from 5 μM to 1.2mM) and lower detection limit (0.31 μM (S/N=3)) than the carbon cloth-supported Co3O4 nanowire array electrode. Both the three-dimensional network of carbon cloth substrate and the hierarchical nanostructure of binary Co3O4/PbO2 composites make such an electrode have high electrocatalytic activity towards the glucose oxidation. Due to the excellent sensitivity, repeatability and anti-interference ability, the carbon cloth-supported Co3O4/PbO2 nanorod arrays will be the promising materials for fabricating practical non-enzymatic glucose sensors.

Highly dispersed hollow gold-graphene (HAu-G) nanocomposites were synthesized by a two-step method. The immobilization of hollow gold nanoparticles (HAu NPs) onto the surface of graphene sheets was achieved by mixing an aqueous solution of HAu NPs with a poly(N-vinylpyrrolidone)-functionalized graphene dispersion at room temperature. A glassy carbon electrode (GCE) was modified with the nanocomposites, and the as-prepared modified electrode displayed high electrocatalytic activity and extraordinary electronic transport properties. Amperometric detection of dopamine (DA) performed with the HAu-G modified electrode exhibits a good linearity between 0.08 and 600 μM with a low detection limit of 0.05 μM (S/N=3) and also possesses good reproducibility and operational stability. The interference of ascorbic acid (AA) and uric acid (UA) can be excluded when using differential pulse voltammetric technique. In addition, this type of modified electrode can also be applied to the determination of DA content in dopamine hydrochloride injection. It is obvious that the HAu-G modified electrode provides a new way to detect dopamine sensitively and selectively.

A indirect method based on a genetic algorithm (GA) and a support vector machine (SVM) which aimed at assessing the environmental harm of a ship oil spill accident was proposed. Five principal affecting factors such as oil quantity, oil specific gravity, ocean climate, environmental sensitivity and oil cleaning situations of famous cases which were accepted by the International Fund for Compensation for Oil Pollution were quantified by fuzzy mathematics to be the input feature vector, while the amends amounts were the output vector. In order to attain higher accuracy, the GA was adopted to optimize all the parameters globally. The results showed that the average relative error was 7.9 percent which proved the method to have higher accuracy. The method has practical reference value to some extent on the environmental damage amendment assessment of a ship oil spill accident.

In this study, free porcine hepatocytes suspension (Group A), porcine hepatocytes embedded in collagen gel (Group B), porcine hepatocytes cultured with PLA-O-CMC nanoparticles and embedded in collagen gel (Group C), and PLA-O-CMC nanoparticles alone (Group D) were transplanted into peritoneal cavity of ALF rats, respectively. The result showed that plasma HGF levels were elevated post-transplantation with a peak at 12 hr. The rats in Group C showed highest plasma HGF levels at 2, 6, 12, 24 and 36 hr post-transplantation and lowest HGF level at 48 hr. Plasma VEGF levels were elevated at 48 hr post-transplantation with a peak at 72 hr. The rats in Group C showed highest plasma HGF levels at 48, 72, and 96 hr post-transplantation. The liver functions in Group C were recovered most rapidly. Compared with Group B, Group C had significant high liver Kiel 67 antigen labeling index (Ki-67 LI) at day 1 post-HTx ( ). Ki-67 LI in groups B and C was higher than that in groups A and D at days 5 and 7 post-HTx. In conclusion, intraperitoneal transplantation of porcine hepatocytes cultured with PLA-O-CMC nanoparticles and embedded in collagen gel can promote significantly liver regeneration in ALF rats.

The asymmetric unit of the title compound, [Fe(C8H7N3)3]2[SiMo14O44], consists of a complex [Fe(C8H7N3)3]2+ cation and half of a derivative of an α-Keggin-type anion, [SiMo14O44]4−. In the mixed-valent MoV/VI anion, the α-Keggin type core is capped on two oppositely disposed tetragonal faces by additional (MoO2) units. The [SiMo14O44]4− anion shows disorder. Two O atoms of the central SiO4 group (overline{1} symmetry) are equally disordered about an inversion centre. Moreover, two of the outer bridging O atoms and the O atoms of the capping (MoO2) unit are likewise disordered. The Fe2+ cation is surrounded in a slightly distorted octahedral coordination by six N atoms from three 3-(2-pyridyl)-1H-pyrazole ligands. N—H...O hydrogen bonding between the cations and anions leads to a consolidation of the structure.

The asymmetric unit of the title compound, [Zn(C8H7N3)3]2[SiMo12O40]·6H2O, consists of a complex [Zn(C8H7N3)3]2+ cation, half of a Keggin-type [SiMo12O40]4− heteropolyanion and three uncoordinated water molecules. The Zn2+ cation is surrounded in a distorted octahedral coordination by six N atoms from three chelating 3-(2-pyridyl)pyrazole ligands. In the heteropolyanion, two O atoms of the central SiO4 group (overline{1} symmetry) are equally disordered about an inversion centre. N—H...O hydrogen bonding between the cations, anions and the uncoordinated water molecules leads to a consolidation of the structure.