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Charity crowdfunding has become one of the most important donation channels in the Internet age. Faced with complex personality traits, can charity crowdfunding platforms attract a wide range of people to make donations? By integrating personality theory with cognitivist learning theory (SOR), and with the help of 449 questionnaire data, this paper examines the psychological mechanisms of altruistic and egoistic personality traits participating in crowdfunding donations and reveals the mediating role of media cognition and donation cognition. The study found that individuals with both altruistic and egoistic personality characteristics have the intention to donate in the context of crowdfunding platforms, and the formation of the intention to donate depends on the individual's cognition of crowdfunding donations, including the cognition of crowdfunding (media trust perception) and perception of donation (donation motivation), specifically, in the relationship between personality characteristics and donation intention, the three media trusts (donation platform trust perception, project initiator trust perception, and project text content trust perception) and three kinds of donation motivations (sympathy, guilt, and satisfaction) play an important mediating role, and the mediating mechanisms of altruistic and egoistic personality are slightly different. The research results have certain implications for the development of philanthropy in the Internet context.

Norcantharidin (NCTD) is a demethylated analogue of cantharidin. It was recently demonstrated that NCTD reduces iron contents in the liver and spleen of mice in vivo, indicating that NCTD can affect iron metabolism via hepcidin. Here, we investigated the effects of NCTD on expression of iron storage protein ferritin-light chain (Ft-L), transferrin receptor 1 (TfR1), divalent metal transporter 1 (DMT1), ferroportin 1 (Fpn1), hepcidin, iron regulatory protein 1 (IRP1), IL-6, p-JAK2 and p-STAT3 in lipopolysaccharides (LPS)-treated RAW264.7 cells in vitro via Real-time PCR and Western blotting analysis. We demonstrate that NCTD down-regulates Ft-L, hepcidin, IL-6, pJAK2, pSTAT3 and up-regulates TfR1, DMT1, Fpn1 and IRP1 expression in LPS treated cells, showing that NCTD can inhibit hepcidin via the IL-6/JAK2/STAT3 signalling pathway and also increase TfR1, DMT1 and Fpn1 expression via down-regulating hepcidin and up-regulating IRP1. Our findings provide further evidence in vitro for the role of NCTD in iron metabolism. A hypothetical scheme for NCTD to affect the expression of iron transport, storage and regulatory proteins or mRNA in LPS-treated RAW264.7 cells. NCTD downregulates hepcidin by inhibiting the IL-6/JAK2/STAT3 signaling pathway and up-regulates Fpn1 via down-regulation of hepcidin. The upregulation of TfR1 and DMT1 expression is mainly induced by increased IRP1 expression. The positive effect of NCTD on Fpn1 may be more significant than its effect on TfR1 expression, leading to a reduced amount of iron intake relative to iron release and hence reduced Ft-L expression under inflammatory conditions. (Solid-line: a major (dominant) role, Dotted-line: a minor role).

Hole doping and biaxial tensile strain on T-graphene can increase its superconducting Tc to a value higher than those of the pristine T-graphene and many other 2D carbon-based superconductors.

Background At present, minimally invasive endoscopic treatment is mostly used for patients with actively bleeding Dieulafoy's lesions, , as it has the advantages of minimal trauma, short operation time and good hemostatic effect, although bleeding can easily recur postoperatively. Recently, extensive gastric cuneiform resection has been advocated for use in these patients because the constant-diameter artery follows a long path to the gastric mucosa. Case summary A 47-year-old man was admitted to the hospital for repeated hematemesis and black stool, and he was diagnosed with Dieulafoy's disease. We chose a method that not only simulates surgical gastric cuneiform resection but also reduces trauma. We performed enlarged local endoscopic full-thickness resection of the gastric wall and abdominal constant-diameter artery and sutured the gastric wall. Postoperative follow-up showed that the constant-diameter artery had been resected from the gastric wall, which was confirmed to have no blood flow signals by endoscopic ultrasonography. Conclusion Endoscopic full-thickness resection of the gastric wall and abdominal constant-diameter artery with suturing of the gastric wall has demonstrated potential as a new treatment for Dieulafoy's disease.

Organophosphate esters (OPEs) and phthalic acid esters (PAEs) are widespread contaminants in the environment. The variations of these chemicals in plants throughout their life cycle is little known. In this study, OPEs, OPE metabolites, and PAEs in peanut and corn grown under field conditions, soil, and air were measured to understand the uptake and translocation, distributions in the plant compartments, and metabolism in the plants. The soil concentrations showed an enrichment effect of OPEs onto the rhizosphere soil but a depletion effect of PAEs on rhizosphere soils. The PAE concentrations between peanut (with a mean of 1295 ng/g dw) and corn (3339 ng/g dw) were significantly different, but the OPE concentrations were not significantly different (with means of 15.6 and 19.2 ng/g dw, respectively). OPE metabolites were also detected in the plants, with lower concentrations and detection rates. Similarities and differences in the temporal variations of the concentrations of traditional OPEs, novel OPEs, and PAEs in plants during their growth were observed. The variations were dependent on both plant species and particular tissues. The leaf compartment is the most important reservoir of OPEs and PAEs (but not OPE metabolites) for both species, highlighting the importance of an aerial uptake pathway. The chemicals have a low potential to be translocated into peanut and corn kernels, reducing their risks via food consumption. Less hydrophobic compounds have higher root concentration factors in this study. These observations differ from those of previous hydroponic experiments.

Background. Ulcerative colitis (UC), a chronic inflammatory bowel disease, is characterized by abdominal pain, diarrhea, and mucopurulent bloody stool. In recent years, the incidence and prevalence of UC have been increasing consistently. Five-flavor Sophora falvescens enteric-coated capsule (FSEC), a licensed Chinese patent medicine, was specifically used to treat UC. This review was aimed to assess the effectiveness and safety of FSEC for the treatment of UC. Methods. Six electronic databases were searched from inception to March 2021. Randomized clinical trials (RCTs) comparing FSEC or FSEC plus conventional Western medicine with conventional Western medicine in participants with UC were included. Two authors screened all references, assessed the risk of bias, and extracted data independently. Binary data were presented as risk ratios (RRs) with 95% confidence intervals (CIs) and metric data as mean difference (MD) with 95% CI. The overall certainty of the evidence was assessed by GRADE. Results. We included 15 RCTs (1194 participants, 763 in the FSEC group and 431 in the control group). The treatment duration ranged from 42 to 64 days. Twelve trials compared FSEC with conventional Western medicine, and two trials compared FSEC plus conventional medicine with conventional medicine. Another trial compared FSEC plus mesalazine with compound glutamine enteric capsules plus mesalazine. FSEC showed a higher clinical effective rate (improved clinical symptoms, colonoscopy results, and stools) (RR 1.12, 95% CI 1.05 to 1.20; 729 participants; 8 trials; low-quality evidence) as well as the effective rate of traditional Chinese medicine (TCM) syndromes (RR 1.10, 95% CI 1.01 to 1.20; 452 participants; 5 trials; low-quality evidence) compared to mesalazine. There was no significant difference in the adverse events between FSEC and control groups. Conclusions. FSEC may show effectiveness in UC treatment compared to conventional medicine, and the use of FSEC may not increase the risk of adverse events. Due to the limited number of clinical trials and low methodological quality of the included trials, our findings must be interpreted with discretion.

The present study aimed to explore the effect of Erxian Decoction on proteomics of osteoblasts stimulated by hydrogen peroxide(H_2O_2) and its protective mechanism with the H_2O_2-induced cell model of oxidative stress. The primary osteoblasts were cultured from the skulls of newborn rats(within 24 hours) and divided into a control group, a model group, a Fosamax group, and an Erxian Decoction group. Blank serum was added in the control group and model group, and the drug-containing serum was added correspondingly to the remaining two groups. After 45 hours, H_2O_(2 )stimulation was conducted for three hours except for the control group, followed by protein extraction. Nano-LC-LTQ-Orbitrap system was used for protein detection, Protein Discovery for protein identification, and SIEVE for quantitative and qualitative analysis. Furthermore, following the blocking of PI3 K signaling pathway by LY294002(10 μmol·L~(-1)), a control group, a model group, an LY294002 group, an Erxian Decoction group, and an Erxian Decoction + LY294002 group were set up to observe the effect of Erxian Decoction on cell proliferation, alkaline phosphatase(ALP) activity, and the relative expression of BMP-2, OPG, p-Akt, p-FoxO1 of osteoblasts stimulated by H_2O_2 under LY294002 intervention. The results revealed that 78 differential proteins were discovered between the Erxian Decoction group and model group, which were involved in the regulation of PI3 K/Akt, glucagon, estrogen, insulin, and other signaling pathways. LY294002 blunted the promoting effect of Erxian Decoction on osteoblast proliferation and significantly down-regulated the expression of OPG and p-FoxO1, whereas its down-regulation on the expression of BMP-2 and p-Akt was not significant. Both LY294002 and Erxian Decoction increased the ALP activity of osteoblasts, which may be related to the cell state and the cell differentiation. The above results suggest that Erxian Decoction can protect osteoblasts stimulated by H_2O_2, with the PI3 K/Akt signaling pathway as one of the internal mechanisms.

Combustion of domestic solid fuels is a significant source of polycyclic aromatic hydrocarbons (PAHs). Some oxygenated PAHs (o-PAHs) and PAHs with molecular weight of 302 (MW302 PAHs) are more toxic than the traditional 16 priority PAHs, whereas their emissions were much less elucidated. This study characterized the size-dependent emissions of parent PAHs (p-PAHs), o-PAHs, and MW302 PAHs from various combustion sources. The estimated emission factors (eEFs) from biomass burning sources were highest for most of the PAHs (391-8928 μg/kg), much higher than that of anthracite coal combustion (43.0-145 μg/kg), both which were operated in an indoor stove. Cigarette smoking had a high eEF of o-PAHs (240 ng/g). MW302 PAHs were not found in the emissions of smoking, cooking, and vehicular exhausts. Particle-size distributions of PAHs were compound- and source-dependent, and the tendency to associate with smaller particles was observed especially in biomass burning and cigarette smoking sources. Furthermore, the inter-source differences in PAH eEFs were associated with their dominance in fine particles. PAH composition profiles also varied with the particle size, showing increasing contributions of large-molecule PAHs with decreasing sizes in most cases. The size distributions of p-PAHs are much more significantly dependent on their n-octanol/air partition coefficients and vapor pressures than those of o-PAHs, suggesting differences in mechanisms governing their distributions. Several molecular diagnostic ratios (MDRs), including two based on MW302 PAHs, specific to these combustion scenarios were identified. However, the MDRs within some sources are also strongly size-dependent, providing a new explanation for the uncertainty in their application for source identification of PAHs. This work also highlights the necessity for understanding the size-resolved atmospheric behaviors and fate of PAHs after their emission.

Objective. To evaluate the effectiveness and safety of Chinese patent medicine for mild-to-moderate active ulcerative colitis (UC) using network meta-analysis (NMA). Methods. We systematically searched PubMed, Cochrane library, Embase, Sino-Med, China National Knowledge Infrastructure (CNKI), Wanfang, and Chinese Scientific Journal Database (VIP) databases to October, 2020. We included randomized controlled trials (RCTs) on Chinese patent medicine for mild-to-moderate active UC. The main analysis was complemented by network subanalyses and standard pairwise comparisons. Statistical heterogeneity, inconsistencies, and ranking probability were also evaluated. Results. The databases search identified 3222 citations, of which 33 RCTs involving 2971 patients met the inclusion criteria. A total of 15 Chinese patent medicines were analyzed. The overall quality of the included studies was low. Pairwise meta-analysis showed that Chinese patent medicine was superior to Mesalazine in improving disappearances of clinical symptoms, recurrence rate, and Mayo score. Based on decreases in adverse events, results from NMA showed that Xilei powder plus Mesalazine was more effective than other drugs. Other NMA results indicated that Danshen freeze-dried powder plus Mesalazine (RR: 0.13; 95% CI, 0.02–0.78) and Kangfuxin lotion plus Mesalazine (RR: 0.24; 95% CI, 0.07–0.57) were superior to Mesalazine in decreasing recurrence rate. Another NMA result indicated that Kangfuxin lotion plus Mesalazine (RR: 0.00; 95% CI, 0.00–0.02) and Zhi Kang capsule plus Mesalazine (RR: 0.00; 95% CI, 0.00–0.02) were superior to Mesalazine in increasing the disappearance of tenesmus. Conclusion. In the probability sorting, Xilei powder combined with Mesalazine ranked first for having the fewest adverse events, Maintaining Intestines Antidiarrheal Pills combined with Mesalazine ranked first for having the lowest recurrence rate, Xilei powder combined with Mesalazine ranked first for improving disappearance rate of mucopurulent bloody stool/abdominal pain, and Kangfuxin lotion combined with Mesalazine ranked first for improving the disappearance rate of diarrhea/tenesmus. However, there is a lack of direct comparisons among Chinese patent medicines for UC. More multiarm RCTs are needed in the future to provide direct comparative evidence.

Keratinases are becoming biotechnologically important since they have shown potential in hydrolysis of recalcitrant keratins with highly rigid and strongly cross-linked structures. However, the large-scale application of keratinases has been limited by the inefficient expression level and low enzyme activity. In this work, we employed pro-peptide engineering and saturation mutagenesis to construct excellent keratinase variants with improved activities. It turned out that amino acid substitutions at the pro-peptide cleavage site (P1) could accelerate the release of active mature enzymes, resulting in a 3-fold activity increase. Eighteen sites of the pro-peptide area were targeted for codon mutagenesis, and a multisite saturation mutagenesis library of the six potential sites was generated, achieving a significant improvement of keratinase activity from 179 to 1114 units/mL. Also, the mutants exhibited alterant catalytic properties. Finally, fermentation for keratinase production in a 15 L fermenter was carried out, and the enzyme activity reached up to over 3000 units/mL. Our results demonstrated that pro-peptide engineering played a crucial role in high expression and engineering of proteases. This study provides a universal route toward improvement of industrial enzymes that were first synthesized as precursors in the form of pre-pro-protein.

Based on a joint analysis of linear Kelvin wake kinematics and water dispersion relation, the features of several components of ship wake are identified in the spectral domain, such as the “X”-shaped Kelvin wake, the narrow “X”-shaped solitary wave packets, and the cross-shaped turbulent and near-field waves. Alternatively, these components can be separately reconstructed in spatial domain using the inverse Fourier transformation. These relations are verified through numerical simulation of the wakes of a ship moving at different speeds. This wake decomposition is now extended to wake feature analysis of real synthetic aperture radar (SAR) image. It reveals that although the images of ship wake have been modulated by SAR imaging mechanisms in various aspects, their spectral characteristics are closely analogous to that of wake surface elevation. Taking advantage of the loci and shape of the wake spectrum, the transverse wave, the divergent wave, the turbulent wave, and the solitary wave packets can be isolated from the original SAR image with full wake appearance. The reconstructed images of wake components facilitate the further estimation of the direction, speed, length, hull geometry, and propulsion system of the ship. This decomposition can also recover wake components from multiple ship wakes and provide an understanding of their roles on SAR image.

In the context of educational informationization, various artificial intelligence and information technologies are widely used in educational reform and teaching practice. Among them, the intelligent identification and big data analysis systems based on student behaviors in class are very meaningful. This paper establishes a learning situation analysis and quality assessment system on the basis of target detection and behavior recognition under class scenarios, and the quality indicators of the degree of positivity and the degree of negativity are defined to achieve a systematic and quantitative assessment of the participatory status of students in class. The application of this system can provide necessary technical supports for individualized learning of students, effective organization and efficient management of teaching.

Aiming at predicting the maneuverability of the ship in shallow water, KCS was selected as the research object. Static drift motion, pure sway motion, and pure yaw motion were performed to calculate the dimensionless hydrodynamic derivatives of KCS. A commercial software, STAR-CCM+ was used to simulate various kinds of movement conditions, by which the force and moment on the hull can be monitored. Then, through the curve fitting, hydrodynamic derivatives of KCS were predicted, and the maneuverability of KCS can be predicted.

Small targets detection is one of the key technical problems in these fields such as maritime surveillance and disaster rescue. In order to find the target as early as possible, the small target detection algorithm based on sea-sky line extraction is generally adopted, and the accurate extraction of the sea-sky line becomes the basis of the small target detection in the maritime. For the panoramic sea images acquired by the catadioptric panoramic vision system, the sea-sky line extraction algorithm is studied in this paper. The specificity of panoramic vision system creating images makes sea-sky line in a panoramic image an approximate circle. A detection algorithm based on gradient direction is proposed to extract accurately the circular sea-sky line. Experimental results show the efficiency and superiority of the proposed method in this paper.

Purpose: To explore the effects of unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) on traumatic disseminated intravascular coagulation (DIC). Methods: A total of 77 cases of severe trauma (APACHE II score: 5 – 10) with DIC were collected and randomly assigned to one of three groups: LMWH treatment - 26 cases were subcutaneously injected with LMWH (75–150 units/kg/d); UFH treatment - 25 cases were subcutaneously injected with UFH (100 – 250 units/kg/d); control - 26 cases supplemented with blood coagulation factor only. Daily mortality in the intensive care unit (ICU), hospitalization time, bleeding rate, thrombin time, prothrombin time, activated partial thromboplastin time, and levels of fibrinogen, antithrombin III (ATIII), and D-dimer were recorded and analyzed. Results: In ICU, LMWH and UFH treatments resulted in lower mortality than in the control group. In addition, hospitalization time was longer in patients treated with LMWH and UFH than in control patients. No significant differences were found between LMWH-treated and control patients in terms of bleeding rate, but UFH-treated patients had lower bleeding rates than control patients. Multifactor analysis indicate a strong relationship between ATIII levels and bleeding rate. Conclusion: The results indicate that low-dose UFH and LMWH are effective options for the treatment of DIC. Keywords : Trauma, Disseminated intravascular coagulation, Unfractionated heparin, Low-molecularweight heparin, Fibrinogen, Antithrombin

In order to study the mode excitation of the unidirectional air waveguide, we place a line source at different positions in the waveguide. The source position plays an important role in determining the result of the competition of the even mode and the odd mode. For the source at the edge of the waveguide, the odd mode gets advantage over the even mode. As a result, the odd mode is excited, but the even mode is suppressed. For the source at the center of the waveguide, the even mode is excited, but the odd mode is suppressed. With two sources at two edges of the waveguide, the even mode is released because the two odd modes are canceled.

Beta-tricalcium phosphate (β-TCP) has been widely used for bone regeneration for many years. However, there are few studies on the osteoconduction ability of different shaped β-TCP scaffolds. In this study, we compared the osteoconductive potential between the tubular and cylindrical β-TCP scaffolds in long bone defect animal model. The results showed that more regenerated bone and a better healing property were observed in tubular group than that in cylindrical group. By hematoxylin-eosin staining, the central part of the callus was more compacted in tubular group. And moreover, the increased osteocalcin and osterix expression were found in tubular group, suggesting more vigorous regeneration of bone defect. These results demonstrated that tubular β-TCP scaffold would be more benefit to promote bone regeneration, indicating that tubular β-TCP scaffold has a good potential for long bone defect repair in clinical practice. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1934-1940, 2018.

The traditional control has good performance in the control of linear systems while has poor performance in the control of nonlinear systems. The bearingless asynchronous motor is a multivariable nonlinear system with high coupling. In this paper, the method of adaptive inverse control is proposed for these reasons. Firstly, the mathematical model of the bearingless asynchronous motor is built, and the possibility of the existence of the bearingless asynchronous motor system inverse model is explored. Secondly, since the object to be controlled is highly nonlinear and has high variability. In this paper, adaptive inverse fuzzy decoupling control is used to make up the deficiency of traditional adaptive inverse control. Finally, the Matlab simulation model is established. The simulation results show that the control method has good dynamic and static performance.

A bearingless induction motor is a strong coupled complex system, the decoupling control of torque and radial suspension force is the premise of the stable operation of the bearingless induction motor. In this paper, the principle of bearingless induction motor is expounded. The magnetic mathematical models of bearingless induction motor are created. The rotor field oriented control strategy is designed. The control strategy is validated with Matlab/simulink. Real-time simulation model based on dSPACE is given and the platform based on dSPACE is constructed. The results show that this method has good decoupling control performance. The actual system development and experiment process confirms that the dSPACE real-time simulation platform can shorten the development time and facilitate the development process, and save costs during the design and test period.

According to the strong coupling between the electromagnetic torque and radial suspension force, and the difficulty of establishing a precise mathematical model of bearingless induction motor, least squares support vector machine is proposed in this paper. The inverse model approximated by the LS-SVM is connected with the original system, decoupling a complex nonlinear multivariable system into four relatively independent pseudo-linear sub-systems of single input and single output. At the same time, fuzzy PID control strategy is introduced to the pseudo linear system to ensure the robustness and anti-jamming ability of the control system. Then the performance is simulated with Matlab/ Simulink. The theory research and simulation experiment have validated that the decoupling control of inverse system based on least squares support vector machine method can be successfully realized, which between the electromagnetic torque and radial suspension force, and the good performance of dynamic and static state of system can be also obtained.

Compared with the complex structure and unsatisfactory performance of traditional flywheel drive system, the proposed strategy adopts bearingless brushless DC motor as the drive actuator of flywheel. The direct torque control which combines the space voltage vector pulse width modulation is presented to control the system. Moreover, a simulation system is built with Matlab/Simulink toolbox. From the simulation results, the proposed control strategy is verified and the rotor can be stably suspended by suspension force along the central axis.

This paper designs an intelligent fuzzy PID controller of electromagnetic bearing for axial artificial heart pump (AAHP) to achieve re-stable suspension and quick response performance. and Matlab/Simulink is employed to simulate floating process of the rotor and the process of response to displacement disturbance. The simulation results show that the floating overshoot can be inhibited effectively, with the fuzzy PID controller. Fuzzy PID controller can respond to sudden displacement disturbance quickly. Then analyze the simulation waveforms of Fuzzy PID controller and traditional PID controller, verify that the fuzzy PID controller can overcome the shortcomings of traditional PID controller, and increase the control precision of the system and the robustness of the system.

In this paper, a new type of maglev wind generator is proposed. The working principle, structure characteristics and the finite element analysis of the new maglev wind turbine are introduced. The generator consists of a 2 degrees of freedom (DOF) maglev generator and a 3 DOF hybrid magnetic bearing. An eight poles active magnetic bearing with external rotor is added into traditional direct-drive permanent magnet wind generator. The rotor ring is hollowed, which can leads to the self-decoupling for magnetic fields between power generation system and suspension system. Compared with the conventional maglev wind generator, the proposed generator not only shows the same advantages of traditional maglev wind turbines, but also improves the axial length utilization and decrease the cost of motor control.

In this paper, a maximum torque per ampere (MTPA) control strategy based on space vector pulse width modulation (SVPWM) is adopted in a dual three-phase interior permanent magnet synchronous motors (PMSMs) system with a five-leg inverter. The simulation model is established in Matlab/Simulink based on the mathematics model of PMSM and the current control method. And the simulation results of the proposed current control strategy are compared with those ofid=0 method in order to verify the performances and characteristics of MTPA control stategy.

As an important component of maglev wind generators, magnetic bearing should possess the merits of small volume, light weight, lower consumption and so on. A novel low-loss axial hybrid magnetic bearing (HMB) is proposed in this paper, its structure and operation principle are introduced, and the process of producing suspension force is elaborated. Based on equivalent magnetic circuit method, magnetic circuit models of PM and control coil are analyzed and established to deduce the quotation of axial levitation force. The accuracy and the reasonableness of proposed low-loss axial HMB are analyzed and validated by using finite element method (FEM), and the comparison between theoretical calculation and FEM is given, which indicates the proposed HMB exhibits good dynamic response and easy control.

In This paper, a direct torque control (DTC) method for bearingless permanent magnet synchronous motor (BPMSM) based on three-level neutral-point clamped (NPC) inverter is described. Through the analysis of virtual space vector modulation, an independent control strategy is adopted into the suspension winding control and a flux linkage error vector SVM-DTC method supplied by three-level NPC inverter is introduced into the torque windings control. By using the proposed control strategy, the neutral-point voltage variation can be greatly limited and the voltage shifting can be eliminated. The results of simulation verify the feasibility of the control algorithm, the dv/dt of output voltage and the torque ripple are restrained effectively, satisfactory robustness and the good performance of the radial levitation can be achieved in a wide speed range by using the proposed method.

In order to realize the solar photovoltaic (PV) system connecting with grid friendly, a PV system with voltage-controlled inverter based on virtual synchronous generator (SG) is presented. This kind of system has features of SG, which supply the virtual moment of inertia to grid. The mathematical model of PV and virtual SG is built, and the control strategy of the maximum power point tracking (MPPT) is also studied in the paper. Simulation model of the grid-connected PV power system is built on Matlab/Simulink. Finally, correctness and feasibility of this system are verified by simulation results.

A high-gain rectangular microstrip patch antenna which is covered by a single layer metamaterial (MTM) superstrate with the near zero refractive index is proposed. The refraction of the metamaterial at frequency 3.51 GHz–3.57 GHz is very close to zero. The metamaterial with the near zero refractive index is placed 42 mm above an ordinary rectangular microstrip patch antenna. The effectively zero refractive index behavior of metamaterial superstrate can gather the wave emitted from the microstrip patch antenna and collimate it toward the normal direction of the antenna. The finite element method (FEM) and the finite difference time domain (FDTD) method are used to study the characteristics of this antenna. The results of the two methods indicate that the realized gain of the proposed antenna is increased by more than 6 dB, and the antenna has a flatness high gain in the predicted frequency band, where the proposed MTM is designed to have a near zero index of refraction. Therefore, the high-gain antenna is effectively enhanced based on the near-zero-refractive-index metamaterial.

Removal of phenols from waters and wastewaters is an important issue in order to protect public health and environment. In an effort to develop an effective adsorbent for removal of phenol from aqueous solutions, fly ash cenospheres (FACs), the solid wastes generated from a coal-firing power plant, were modified with an amino-terminated organosilicon (γ-aminopropyltriethoxysilane, KH550). Surface properties of the KH550-modified FACs (M-FACs) were characterized by the X-ray diffraction (XRD), the scanning electron microscopy (SEM) and X-ray photoelectron spectra (XPS). The characterized results showed that KH550 was successfully grated on the surface of FACs. The effects of various experimental parameters such as solution pH, adsorbent dose, and temperature upon the phenol adsorption onto M-FACs were evaluated. The results showed solution pH had a major impact on the phenol adsorption onto M-FACs, the optimum phenol removal was observed around pH 7-9. The kinetic studies indicated that the adsorption process was best described by the pseudo-second-order kinetics, suggesting that the mainly phenol adsorption process was predominantly controlled by chemical process. M-FACs presented more than double adsorptive capacity as compared with FACs. The adsorption capacity of the regenerated adsorbents could still be maintained at 83% by the fourth adsorption-desorption cycle.

A novel attapulgite clay-based composite (BiVO4/attapulgite) was successfully prepared as a heterogeneous photocatalyst for degradation of rhodamine B (RhB) dye solution under visible light irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and microanalysis by energy dispersive spectrometry (EDS), and UV-visible diffuse reflectance spectra (DRS). The results showed that monoclinic BiVO4particles were loaded successfully on to the surface of attapulgite fibers and were widely dispersed. The DRS spectrum reveals that the BiVO4/attapulgite composite had much stronger absorption in the visible light range of 420-800 nm. Correspondingly, the BiVO4/attapulgite composite showed significantly higher activity in degrading RhB solution under visible-light irradiation compared to that of pure BiVO4.

The finite difference time domain (FDTD) method is used to study the characteristics of composite helices patch antenna based on left-handed effect. The numerical results indicate that electromagnetic wave resonance occurs near f = 4.18 GHz where the equivalent permittivity and permeability are both negative. In this case, the electromagnetic wave's tunneling effect and evanescent waves’ enhancing effect are formed. Such effects can improve the antenna's radiation gain and its matching condition, and this composite patch antennas’ return loss is much lower compared to conventional antenna. Due to these advantages, the use of composite square frame patch antennas will be extended to mobile communication, satellite communication, aviation, etc.

The aggregation kinetics of C60 nanoparticles have been investigated over a wide range of monovalent and divalent electrolyte concentrations by employing time-resolved dynamic light scattering (DLS). The results showed that the presence of electrolyte made a dramatic decrease in the surface zeta potential and increase in the particle size. The aggregation kinetics of C60 nanoparticles exhibited reaction-limited and diffusion-limited regimes, which was found to be consistent with the classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of colloidal stability. The critical coagulation concentration (CCC) values of C60 nanoparticles were estimated as 321mM Na+, 295mM K+, 9.6mM Ca2+and 6.7mM Mg2+, which were far higher than the electrolyte concentrations in natural water. The enhanced C60 stability in the presence of humic acid was attributable to steric repulsion. Therefore C60 nanoparticles can be relatively stable in typical aquatic environments.

In this paper, the thermoelastic behavior of Al plate induced by laser pulse is simulated using the commercial software COMSOL Multiphysics. In the simulation, the heat transfer in combination with phase change is considered. The variation of the temperature and stress fields along the thickness direction is obtained and analyzed.

The dynamic response of pipe-on-pipe impact is described by an analytical model. The model considers the impact of a whipping pipe with one end hinged and the other end free on a simply-supported target pipe at its midpoint. Combining with the contact theory, the Laplace transformation, and the inverse Laplace transformation method, an analytical model based on the tubular beam theory is proposed to study the elastic-plastic behavior of a target pipe laterally impacted by a whipping pipe. Numerical simulations using the explicit finite element code MSC/DYTRAN are also performed. The results are coincident with the theoretical prediction.

In order to explore earth penetrator’s effective destruction to the runway, using numerical simulation as the main means, and combined with some experimental data, a study on the intrinsic connection between series of charge weight, different depth of the burst point and damage area of the runway (blasting crater area) is carried out. The results shows that: for the same charge weight of earth penetrator, there is an optimum depth of the burst point (best penetration detonation depth), and the law which is got from numerical simulation is consistent with the experimental one, which indicates that the material model and calculation parameters of numerical simulation are reasonable, the numerical simulation can replace some research experiment and accelerate research progress.