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Low-cost and low-barrier antibiotic stewardship strategies are urgently needed to deal with the widespread problem of antibiotic resistance. Social norm feedback could be a promising strategy. In this mixed-methods systematic review (PROSPERO: CRD42022361039), we aimed to identify the key behaviour change techniques used in social norm feedback for antibiotic stewardship and assess their effectiveness in reducing antibiotic prescribing. We searched PubMed, Embase, Web of Science, and Scopus for peer-reviewed studies published between Jan 1, 2000, and Jan 20, 2022. 3547 studies were screened, of which 23 studies reporting the effects of social norm feedback interventions on antibiotic prescribing met the inclusion criteria. 19 behaviour change techniques were tested in the included studies. The meta-analyses showed that social norm feedback is an effective strategy for reducing antibiotic prescribing, with an overall rate difference of 4% (p0·0001). The behaviour change technique with the highest effective ratio (ER=13) was information about health consequences, followed by instruction on how to perform the behaviour (ER=9) and adding objects to the environment (ER=9). Social norm feedback is a promising strategy to reduce antibiotic prescribing, and can be incorporated into the clinical decision-making support system.

Self-assembly of colloidal particles enables the versatile fabrication of highly ordered structures and materials for optical, sensing, and other applications. Nevertheless, many traditional assembly processes are inefficient, because there exists an inevitable contradiction between time efficiency and crystalline quality. In this work, we introduce an ultrafast, robust, and scalable approach of imbibition-induced assembly. We assume that the instantaneous solvent imbibition induced by the nanoporous media could direct ultrafast self-assembly of colloidal particles into ordered structures.Self-assembly of colloidal particles from a droplet on a nanoporous substrate was firstly observed and investigated. A phase diagram of the thickness of the colloidal crystal as a function of the printing speed and the particle volume fraction was presented through systematic experiments.The nanoporous substrate can induce strong capillary flow that will directthe rapid self-assemblyof particles intocolloidalcrystals. The imbibition-induced assembly was spatially and temporally combined with the meniscus-guided printing approach, and the printing speed can be improved by two orders of magnitude than the traditional evaporative assembly methods. We finally demonstrate an effective and ultrafast approach for assembling colloidal particles into photonic crystals with controllable sizes and shapes on the macroscale.

Multi-view learning can be considered as a kind of classification method which explores common and unique information among different views. For dictionary learning, it can identify informative features by learning sparse representation of samples and has great advantages for classification. However, there are few researches on the problem of multi-view learning with dictionary learning. In order to improve the performance of multi-view classification, we propose a new multi-view dictionary learning with consensus of view(MVDL-CV). First of all, we learn a particular dictionary for each view and obtain the sparse representation of the sample. Then, by utilizing the regularization term between two dictionaries in consensus, we can determine the similarity of samples and obtain the discriminative sparse representation, which can be helpful to construct the improved classifiers . Further, we obtain the solution of the model through an alternating convex optimization method and present the convergence analysis of MVDL-CV. In the experiments, we compare the proposed method with previous multi-view learning methods, and the experimental results show that MVDL-CV is a feasible and competitive method.

Background Inputs of above- and belowground litter into forest soils are changing at an unprecedented rate due to continuing human disturbances and climate change. Microorganisms drive the soil carbon (C) cycle, but the roles of above- and belowground litter in regulating the soil microbial community have not been evaluated at a global scale. Methods Here, we conducted a meta-analysis based on 68 aboveground litter removal and root exclusion studies across forest ecosystems to quantify the roles of above- and belowground litter on soil microbial community and compare their relative importance. Results Aboveground litter removal significantly declined soil microbial biomass by 4.9% but root exclusion inhibited it stronger, up to 11.7%. Moreover, the aboveground litter removal significantly raised fungi by 10.1% without altering bacteria, leading to a 46.7% increase in the fungi-to-bacteria (F/B) ratio. Differently, root exclusion significantly decreased the fungi by 26.2% but increased the bacteria by 5.7%, causing a 13.3% decrease in the F/B ratio. Specifically, root exclusion significantly inhibited arbuscular mycorrhizal fungi, ectomycorrhizal fungi, and actinomycetes by 22.9%, 43.8%, and 7.9%, respectively. The negative effects of aboveground litter removal on microbial biomass increased with mean annual temperature and precipitation, whereas that of root exclusion on microbial biomass did not change with climatic factors but amplified with treatment duration. More importantly, greater effects of root exclusion on microbial biomass than aboveground litter removal were consistent across diverse forest biomes (expect boreal forests) and durations. Conclusions These data provide a global evidence that root litter inputs exert a larger control on microbial biomass than aboveground litter inputs in forest ecosystems. Our study also highlights that changes in above- and belowground litter inputs could alter soil C stability differently by shifting the microbial community structure in the opposite direction. These findings are useful for predicting microbe-mediated C processes in response to changes in forest management or climate.

Glucose is one of the major energy sources in organisms, which also is an important biomarker in clinic diabetes diagnosis. Owing to urgent requirements in clinic diabetes diagnosis, developing glucose detection method with accuracy, sensitivity and stability becomes urgently important. A sensitively and stably photoelectrochemical (PEC) non-enzymatic glucose sensor was constructed using the graphitic carbon nitride/α-Fe2O3 (g-CN/α-Fe2O3) heterojunction. The g-CN/α-Fe2O3 heterojunction was synthesized using a facile hydrothermal process in the presence of ionic liquids. The α-Fe2O3 nanoparticles anchored to the surface of g-CN, which contributed to forming formation the heterojunction between α-Fe2O3 and g-CN. The heterojunction can accelerate the migration of photogenerated carriers, resulting in enhanced PEC performance. As a result, the g-CN/α-Fe2O3 heterojunction achieved the enhancing photocurrent density compared to α-Fe2O3 alone. In addition, the introduction of glucose can boost electron-hole separation, resulting in sensitive PEC tracing of glucose level in aqueous solution. The sensor can trace the contents of glucose among 0.1 to 11.5 mg L−1 with an acceptable stability. Furthermore, the detection limit of the PEC non-enzymatic glucose sensor is significantly lowered to 0.03 mg L−1. It means the PEC non-enzymatic glucose sensor constructed by the g-CN/α-Fe2O3 heterojunction can be a promising platform to detect glucose.

In this paper, a novel Fe-Mn binary oxide-diatomite (FMBO-Dt) composite was prepared by co-precipitation method. The morphological and structural features of the synthesized composite were characterized by X-ray diffraction, Scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The catalytic activity of FMBO-Dt composite was investigated by the degradation of methylene blue (MB) in the presence of H2O2 and the effects of various factors such as Fe/Mn molar ratio, initial pH, and initial H2O2 concentration on MB degradation were evaluated. It was found that FMBO-Dt composite was highly effective for the degradation of MB in the presence of H2O2. In addition, the stability and reusability of the composite was also investigated. Finally, the possible mechanism for the decolorization of MB in the heterogeneous system was proposed. These results suggested that FMBO-Dt composite was a promising candidate for dye wastewater treatment.

One of the effective ways to quantitatively inspect or monitor an industrial structure is to obtain images via either scanning or tomography. A combination of ultrasonic guided wave approach and tomographic technique by employing a reconstruction algorithm for the probabilistic inspection of damage (RAPID) can be used to inspect effectively the damage area via visual images. In this paper, surface cracks in polymer bonded explosives (PBXs) were quantitatively evaluated by a Rayleigh surface wave tomographic approach. Considering the relative low wave velocity in the material tested, special surface wave transducers with silicone wedge were designed and produced. The measured signals of Rayleigh surface wave propagation in the specimen with and without cracks were used in a tomographic algorithm to reconstruct images of defects. Results indicate that the setup of the array of transducers has significant influence on the appearance of images. Optimal transducer array setups were also proposed to measure the ultrasonic wave signals for irregular shaped defects to quantitatively image irregular surface cracks in PBXs. It was shown that the image generated by the proposed approach with the optimal transducer array and shape factor calculation method has good agreement with the real defect shape. The present approach provides an alternative tool that can be applied to detecting, locating and imaging the surface defects in PBXs.

Combination of probabilistic damage imaging (PDI) algorithm and the fusion ultrasonic guided wave damage index can be used to detect the damage in a complicated composite structure with acceptable accuracy. However, the damage signatures associated with PDI algorithm cannot accurately identify multi-defects features such as the number, position and dimension information, which greatly restrict the inspection effect in real practice. In this paper, the damage shape factor βM of each damage-impaired path is optimized to enhance the resolution of PDI algorithm. Then, a modified probabilistic damage imaging (MPDI) algorithm with the βM is proposed to identify the multi-defects existed in the curved carbon/epoxy composite structures. The validity of the algorithm is firstly checked in the curved composite structures with the single defect. The MPDI with the βM is applied to identify the depth of defect. The obtained results show that the precision of different defects identification by the MPDI algorithm is much higher than that used by the PDI algorithm. The number, position and dimension of multi-defects existed in the curved composite structure are clearly imaged by the method. This study also verifies that the majorization of damage shape factor in the MPDI algorithm is practicable and necessary for better identification of multi-defects in composite structure.

Copper-doped manganese oxide nanorod catalysts with various Cu/Mn molar ratios have been prepared for catalytic combustion of Volatile organic compounds (VOCs). The effects of Cu/Mn ratio and calcination temperatures on catalytic performance were investigated. It turned out that the Cu1Mn1-500 sample exhibited the best catalytic combustion performance, to remove toluene at a temperature of 214 °C over 120 h without a significant decrease in toluene conversion. XRD, SEM, HRTEM, XPS were carried out to explore the physicochemical properties of catalysts, and the results demonstrated that doping copper into manganese oxides can contribute to rich oxygen vacancies, high redox capability, and hence increase the catalytic activity. In addition, both the large surface area and high crystallization of the obtained nanorod catalysts are also helpful for the high activity and stability of these copper-manganese mixed metal oxide catalysts. Furthermore, the presence of water vapor had little inhibition effect on the catalytic activity under the reaction condition.

The seismic performance of perforated brick masonry wall was investigated by subjecting six fire-exposed pieces and one unexposed piece to low reversed cyclic loading. Two of the exposed pieces were reinforced with carbon fiber cloth and steel mesh cement mortar. The effect of the fire duration, fire boundary, cooling regime, and reinforcement method on the failure characteristics of the specimens was investigated. The experimental results revealed that (i) for the same position, the temperature of the mortar was higher than that of the brick and (ii) the cracking load and ultimate load of the walls decreased progressively with increasing fire duration. Moreover, the ultimate bearing capacity of the wall reinforced by carbon fiber cloth and steel mesh cement mortar was higher than that of the wall subjected to the same fire duration. This capacity was also higher than that of the unexposed wall.

The current theoretical work investigates multiple scattering of surface waves from shallow cavities at the surface of an elastic half-space. The multiple scattered field is shown to be equivalent to the field generated by the application of a distribution of tractions, obtained from the incident wave, on the surfaces of the cavities. Using a self-consistent method, an analytical approach is proposed to derive an explicit set of equations which approximate the multiple scattered field. Its far-field displacement amplitude is then calculated and verified by numerical calculation obtained by the boundary element method (BEM). The analytical and BEM results are graphically presented and show excellent agreement when the depths of cavities are small compared to the wavelength. The improvement of the proposed approach relative to a first order approximation is reported and its limitations are discussed based on the results of comparison.

We theoretically investigate the Fano resonance and Rabi splitting in the metal–dielectric–metal plasmonic waveguides with stub resonators. The proposed nanostructure waveguide consists of bulb-like resonators and a thin Metamaterial (MM) baffle. The bulb-like resonator with low Q factor can work as a continuum state, and the plasmonic waveguide inserted with a MM baffle can work as a discrete state. Fano resonances are obtained because of the interaction between the two states in the structure and the Fano resonance can be tuned by changing the separation between the resonator and the MM baffle. In the plasmonic waveguide system with two resonators and a MM baffle, Rabi splitting occurs because of the strong coupling between the narrow spectral response of MM baffle and the Fabry–Perot resonance caused by the two bulb-like resonators The pronounced anticrossing behavior of the splitting peaks can be modified by varying the resonant frequency of MM baffle, the bulb-like resonator’s radius and the stub height. Furthermore, it is also found that the Rabi splitting can also be tuned by the separation between resonator and the MM baffle. Such plasmonic waveguide system may have potential applications in providing a stimulating insight to explore new fundamental physics in analogous atomic systems.

We show a superplastic diffusion bonding method to join metallic glasses (MGs) via high-speed heating at 2000 K/min taking a timescale of the order of microseconds to milliseconds at ambient pressure because the minimum viscosity of supercooled liquid drastically decreases as the heating rate increases. The results show strong metallic bonds are formed but the amorphous structure is still maintained. Finally, we establish a general equation containing the involved parameters for high-speed heating bonding. This method provides a new path to join MGs rapidly and benefits for improving the critical size of MGs.

Due to the toxicity and carcinogenicity, antimony and its compounds have been included as priority pollutants by Environmental Protection Agency of the United States (USEPA) and the European Union (EU). The removal methods of antimony need to be further studied. In this study, nZVI/Fe3O4 nanocomposites were synthesized, characterized, and applied to remove Sb(III). The nZVI/Fe3O4 nanocomposites before and after reaction with Sb(III) were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), vibrating sample magnetometry (VSM), and X-ray photoelectron spectroscopy (XPS). nZVI/Fe3O4 nanocomposites have a maximum Sb(III) adsorption capacity of 87.6 mg/g at pH 7.0. The removal of Sb(III) was a complex process including surface adsorption and oxidation. The removal of Sb(III) mainly involved three processes: (1) most Sb(III) was adsorbed on the surface of nZVI/Fe3O4 nanocomposites; (2) part of Sb(III) was rapidly oxidized to less toxic Sb(V); and (3) the generated Sb(V) was further adsorbed on the surface of nZVI/Fe3O4 nanocomposites. The nZVI/Fe3O4 nanocomposites can be separated from solution with an external magnet. The high Sb(III) removal efficiency and rapid separability of nZVI/Fe3O4 nanocomposites exhibited the great potential for the removal of Sb(III) from wastewater.

Targeting the autophagy process is considered to be a promising new strategy for drug treatment of ovarian cancer. α-Tomatine, a steroidal alkaloid extracted, is mainly isolated from leaves, roots and immature green tomatoes. α-Tomatine has biological activities such as anticancer, antioxidative and anti-inflammatory. The study aimed to explore the effects of α-tomatine on proliferation, apoptosis and autophagy and the underlying mechanisms in ovarian cancer Skov3 cells. After treatment with different concentrations of α-tomatine (0, 0.75, 1 and 1.5 μM) in Skov3 cells for 24 h, proliferation was determined by the CCK-8 assay, and apoptosis was detected by flow cytometric analysis. Autophagy in cells was determined by the number of fluorescent spots using confocal fluorescence microscopy after mRFP-GFP-LC3 transfection. The relationship between autophagy and apoptosis was proved by Beclin-1 overexpression. The protein expression levels were tested by western blotting. The results demonstrated that α-tomatine effectively repressed proliferation, exerted a proapoptotic effect and inhibited early-stage autophagy in Skov3 cells in a dose- and time-dependent manner. Additionally, Beclin-1 overexpression significantly suppressed α-tomatine-treated apoptosis in Skov3 cells, indicating that α-tomatine inhibits autophagy to induce apoptosis. We also found α-tomatine inhibited the protein expression levels of PI3K/Akt/mTOR signaling pathway. However, the autophagy inhibition of α-tomatine could be reversed obviously by Beclin-1 overexpression. Taken together, α-tomatine inhibited autophagy through Beclin-1. Our study suggests that α-tomatine, as a novel early-stage autophagy inhibitor, might be a potential drug for further treatment of ovarian cancer by inhibiting proliferation and promoting apoptosis.

Nonlinear guided wave has been recognized as a potential means to characterize the state of material microstructures in solids. However, nonlinear guided wave approaches based on second harmonic generation or combined harmonic generation induced by counter-directional wave mixing, are applicable only under the condition that transmitters and receivers are placed at two different ends of the tested structures. These approaches are not effective for characterization of the structures with only one accessible end. In this paper, modeling of the backward combined harmonic at difference frequency induced by one-way mixing of two primary co-directional guided waves is investigated in a circular pipe, where the transmitters and receivers are placed at the same end of the pipe. The backward combined harmonic, generated at difference frequency and propagating in the direction opposite to that of two primary co-directional guided waves, is successfully observed numerically. A strong frequency mixing response characterized by a cumulative growth effect of the generated backward combined harmonic is demonstrated. The use of the generated backward combined harmonic for localized material degradation characterization and location is numerically examined in the given pipe. The obtained results indicate that the use of the backward combined harmonic can locate and characterize the localized material degradations in the given pipe by controlling the mixing zone of two primary co-directional guided waves. This study provides a promising means for characterization of localized degradations in pipes.

The curved composite structures are popularly used in the aerospace field for their superior properties. Complexity of structure and geometry generally limit the inspection or monitoring effect of different types of defects in the curved composite structure. A feasible damage probabilistic tomography algorithm combined with ultrasonic guided wave technology is necessary to be developed for the structural health monitoring of curved composite structures. In this paper, defect zones in a curved composite structure are characterized using the modified probabilistic tomography (MPT) method and fusion of damage index (DI). The MPT with the defect shape factor βM at each damage-impaired path and hybrid DI schemes are proposed to indicate the location and propagation of defect zones in tested sample. The feasibility of proposed approaches is verified on the curved carbon/epoxy composite structure, experimentally. The results show that the MPT and fusion DI methods successfully represent the extension of defect zones in a quantitative manner. It is suggested that the accuracy and reliability of localization results of the MPT algorithm is better than those obtained by the probabilistic tomography (PT) algorithm with the averaged β.

In this study, a facile water-soluble fluorescence sensor 2-((2-hydroxybenzylidene)-amino)-2-(hydroxymethyl)propane-1,3-diol (ST) was synthesized via one-step reaction, and its fluorescence sensing performance for Al3+ both in aqueous solution and on paper substrate was evaluated. The results showed that ST exhibited an specific fluorescence "turn-on" response to Al3+ over other cations in aqueous solution as well as on the test paper. The limit of detection was found to be 3.2×10-7M, which revealed that the obtained Schiff-base based fluorescence chemosensor ST possessed a great potential for the rapid, quantitative and qualitative detection of Al3+.

The propagation characteristics of feature guided waves (FGWs) in topographical waveguides, such as welded joints, have been widely investigated. However, most of these investigations analyzed linear acoustic characteristics. Considering the high sensitivity of nonlinear ultrasonic techniques in the nondestructive evaluation of microscopic defects in materials, such as identifying micro-defects at an early stage, it is particularly relevant to investigate the nonlinear acoustic response of FGWs in topographical waveguides. In this paper, we use a theoretical analysis and numerical simulation to investigate the second-harmonic generation (SHG) of FGWs in a welded joint. The theoretical framework is firstly expounded based on the reciprocity relation and modal expansion with the nonlinear semi-analytical finite element (SAFE) method and perfectly matched layers. Numerical models are implemented to predict the effect of SHG of FGWs in a welded joint. Two families of FGW propagation in a welded joint are analyzed. The results obtained demonstrate that mode conversion and the cumulative effect of the generated second harmonics can be observed in the welded joint. This investigation provides new physical insights into SHG for FGW propagation.

Snowpack in winter is very sensitive to climate change, and may in turn induce complex effects on terrestrial biochemistry processes. Here we synthesized the results from 49 papers based on snow depth manipulation experiments and conducted a meta-analysis to evaluate the general response of 9 variables related to terrestrial carbon pools and dynamics to the altered snowpack depth. Our meta-analysis results indicated that increasing snowpack depth significantly increased litter biomass (+18.4%), MBC (+18.2%) and CO2 emission (+15.5%), and significantly decreased litter C: N ratio (−5.8%) and total soil carbon (−28.5%) under snow addition manipulation, but did not significantly affect fine root biomass, MBC: MBN ratio and soil dissolved organic carbon (DOC). However, increasing snowpack depth only significantly altered litter C: N ratio (+11.2%) under snow removal manipulation. The different responses between snow addition and removal were possibly related to the higher soil temperature and moisture under snow addition than under snow removal manipulation experiments. In addition, the effect of increasing snowpack depth on CH4 flux was not significant, presumably because all these studies were compiled from snow-removal experiments. These results are useful for a better understanding of the effects of altered snowpack on terrestrial carbon cycling under climate change scenarios.

The use of guided wave tomography has become an attractive alternative to convert ultrasonic wave raw data to visualized results for quantitative signal interpretation. For more accurate life prediction and efficient management strategies for critical structural components, there is a demand of imaging micro-damages in early stage. However, there is rarely investigation on guided wave tomographic imaging of micro-defects. One of the reasons for this might be that it becomes challenging to monitor tiny signal difference coefficient in a reliable manner for wave propagation in the specimens with micro-damages. Nonlinear acoustic signal whose frequency differs from that of the input signal can be found in the specimens with micro-damages. Therefore, the combination of guided wave tomography and nonlinear acoustic response induced by micro-damages could be a feasibility study for imaging micro-damages. In this paper, the nonlinear Rayleigh surface wave tomographic method is investigated to locate and size micro-corrosive defect region in an isotropic solid media. The variations of acoustic nonlinear responses of ultrasonic waves in the specimens with and without defects are used in guided wave tomographic algorithm to construct the images. The comparisons between images obtained by experimental signals and real defect region induced by hydrogen corrosion are presented in this paper. Results show that the images of defect regions with different shape, size and location are successfully obtained by this novel technique, while there is no visualized result constructed by conventional linear ultrasonic tomographic one. The present approach shows a potential for inspecting, locating and imaging micro-defects by nonlinear Rayleigh surface wave tomography.

Microporous carbon material with a high surface area of 1562 m 2 /g is prepared via an impregnation method with NaY zeolite as hard template. The results indicate that glucose, an environmental friendly material, could be used as the carbon precursor of zeolite templated carbons, in comparison with the toxicity of furfuryl alcohol and lower surface area of carbons generated from sucrose. Effects of reactant molar ratios and carbonization conditions on the textural properties are addressed. Although higher carbonization temperature favors more complete carbonization reactions, it also causes the collapse of small pores and the formation of large pores at the same time. Further characterizations of the obtained carbon materials with XRD, SEM and N 2 adsorption–desorption measurements are presented. Methane adsorption tests on carbon materials are investigated with the static volumetric method at 300 K. The higher adsorption amount of 9.9 wt.% was achieved at 3.5 MPa on sample with a higher micropore volume, indicating that micropores were playing a crucial role for the methane storage process.

In this work, thiol-functionalized MnFe2O4-MCM-41 (MnFe2O4-MCM-41-SH) was applied to remove Sb(III) from wastewater. Superparamagnetic MnFe2O4 nanoparticles were incorporated onto the thiol-functionalized MCM-41, which not only solved the aggregation problem of MnFe2O4 nanoparticles and the difficulty in separation of MCM-41, but also improved adsorption efficiency for Sb(III). The removal of Sb(III) by MnFe2O4-MCM-41-SH was investigated through batch experiments. The research results showed excellent adsorption performance and re-usability of MnFe2O4-MCM-41-SH. According to the Langmuir isotherm model, the maximum adsorption capacity of Sb(III) by MnFe2O4-MCM-41-SH is 164.8 mg/g. The Sb(III) removal efficiency was around 89.1% in the fifth cycle by MnFe2O4-MCM-41-SH with desorption treatment. On the basis of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy, the Sb(III) removal mechanism was discussed. The reaction mechanism between Sb(III) and MnFe2O4-MCM-41-SH was complex, involving surface adsorption, oxidation, and reduction. In view of magnetic property and the high removal efficiency of Sb(III), MnFe2O4-MCM-41-SH is a promising adsorbent for Sb(III).

Low efficiency of energy transition is generally considered to be the only weakness of electromagnetic ultrasonic transducers (EMATs). Electromagnetic acoustic resonance (EMAR) technique has been successfully used to overcome this disadvantage with a combination of the EMATs with the ultrasonic resonant method. In this paper, a nonlinear EMAR technique has been proposed to evaluate the thermal damage of metallic materials, which combines the feature of EMAR with the merit of higher harmonic generation that provides an effective indicator to material damage. The use of contactless EMATs can isolate the material nonlinearity and maintain the coupling condition consistently on measurements of higher harmonics generated. EMAR provides high enough signal magnitude for higher harmonic generated. An experimental scheme is proposed and applied to assess the thermal damage in aluminum and nickel plates. In addition, conventional EMAR techniques based on the measure of shear wave velocity and attenuation within a certain frequency range, are also carried out for the specimens. The experimental results show a monotonic relationship between the normalized amplitude of higher harmonic generated and the artificial thermal loading time, while no stable trends are observed by conventional linear EMAR approaches. The results in this paper indicate that nonlinear EMAR technique proposed can be used to assess the thermal damage in both nonferromagnetic and ferromagnetic materials, with improved reliability and sensitivity over linear one.

Ultrasonic guided wave tomography provides an imaging potential over a hidden and inaccessible damage zone. The use of shear horizontal guided waves has been proposed as an attractive technique for surface defect characterization. In this study, the quantification and imaging of corrosion wall thinning in a plate are investigated by using shear horizontal guided waves. Simulations of shear horizontal wave propagation in the specimens using hybrid boundary element method are studied in this paper. Magnetostrictive patch transducers are designed to generate and measure the shear horizontal wave mode experimentally. The quantification via imaging of wall thinning is achieved by a modified reconstruction algorithm for the probabilistic inspection of damage tomography algorithm. The comparisons of the imaging obtained by modeling data and experimental ones of defects with different shapes in the specimens are presented in this paper. The results obtained by experimental tests are comparable with that produced by boundary elements method. The present approach provides an alternative tool, that can be applied to detecting, locating and imaging the wall thinning defects in plate-like structures.

Global atmospheric nitrogen deposition has increased steadily since the 20th century, and has complex effects on terrestrial ecosystems. This work synthesized results from 54 papers and conducted a meta-analysis to evaluate the general response of 15 variables related to plant root traits to simulated nitrogen deposition. Simulated nitrogen deposition resulted in significantly decreasing fine root biomass (

The use of nonlinear ultrasonics wave has been accepted as a promising tool for monitoring material states related to microstructural changes, as it has improved sensitivity compared to conventional non-destructive testing approaches. In this paper, third harmonic generation of shear horizontal guided waves propagating in an isotropic plate is investigated using the perturbation method and modal analysis approach. An experimental procedure is proposed to detect the third harmonics of shear horizontal guided waves by electromagnetic transducers. The strongly nonlinear response of shear horizontal guided waves is measured. The accumulative growth of relative acoustic nonlinear response with an increase of propagation distance is detected in this investigation. The experimental results agree with the theoretical prediction, and thus providing another indication of the feasibility of using higher harmonic generation of electromagnetic shear horizontal guided waves for material characterization.

Aptamers are short DNA/RNA oligonucleotides selected by a process known as Systematic Evolution of Ligands by Exponential Enrichment (SELEX) based on affinity for target molecules. Since aptamers have several advantages over monoclonal antibodies, such as high specificity and affinity, flexible modification and stability, and lack of toxicity and immunogenicity, they are promising novel diagnostic and therapeutic agents. In this review, we will describe the development of aptamers against thrombin, von Willebrand factor (vWF), factor IX, and factor XII as potential anticoagulants or antithrombotics for cardiovascular diseases, especially those that have entered clinical trials.

The power supply control system is one of the most important local control systems of HL-2M tokamak. The power supply system of HL-2M is composed of four flywheel generator sets with total capacity of 600 MVA, all the magnetic field coil power supplies and high voltage power supplies of auxiliary heating system. The control system of power supply should make sure the large amount of on-site equipment and facilities to operate steadily and reliably. This paper presents the architecture of HL-2M control system and four kinds of established control networks. It describes how the power supply control system is built by using the established hardware structures and software agreements. Specially, it is focused on introducing an application of real-time technology based on the reflective shared memory and the fully digital compact solution for controlling the high power converters. Otherwise, a scheme which adopts PROFINET and Sequence of Events technology to carry out the intellect interlock control system is given.

The enhanced performance of the ozone-enhanced photocatalysis process (O 3 -PCO) on toluene destruction was evaluated and its mechanism was investigated. The toluene removal efficiency (TRE) and stability of O 3 -PCO was compared with that of conventional PCO. The gaseous intermediates of toluene oxidation in various processes were analyzed by GC–MS. The formation pathways of main oxidants and their role in toluene destruction were studied. Results indicated that the TRE of O 3 -PCO was 8 times higher than that of PCO because more oxidants were generated besides hydroxyl radicals (OH ). The generation rate and amount of OH was remarkably increased in the O 3 -PCO process which contained more pathways (such as UV/O 3 and O 3 /TiO 2 ) to produce OH besides UV/TiO 2 . The GC–MS results showed that the types and amounts of byproducts were dramatically reduced due to the formation of more oxidants and complete oxidation, leading to remarkable enhancement of the photocatalyst's durability in the O 3 -PCO process. Its mechanism was greatly different from the conventional PCO. Both OH and active oxygen (O ) played a key role in the O 3 -PCO process. Based on the intermediates and the main oxidants, possible pathways of toluene degradation were proposed.

A simple optical vernier filter with cascaded double-coupler compound fiber loop resonators is proposed. The proposed filter consists of two individual double-coupler compound fiber loop resonators. The circulating and transmitted output fields and intensities, as well as some performance parameters such as the contrast, finesse and free spectral range, are computed and presented in graphical form. A comparison between this proposed vernier filter and one individual double-coupler compound fiber loop resonator is made. The simulation results show that the contrast and finesse of the proposed vernier filter can be increased remarkably compared to the individual one double-coupler compound fiber loop resonator. And it is found that the free spectral range of the proposed filter can be enhanced by the vernier operation. These results are useful when the proposed vernier filter is used to construct narrow-bandwidth filters and single-frequency fiber lasers.

The Au/CeO2 catalysts were synthesized by co-precipitation (CP), deposition-precipitation (DP) and metallic colloids deposition (MCD) method, and tested for oxidation of volatile organic compounds (VOCs). It was revealed that the Au/CeO2 catalyst prepared by DP method was the most efficient catalyst towards the total oxidation of toluene. The Au/CeO2 catalysts had obviously high catalytic activity, and the best results was obtained on 3 wt.% Au/CeO2 catalyst prepared by DP method. These catalysts were characterized by means of specific surface area (BET), atomic absorption spectroscopy (AAS), X-ray diffraction (XRD), temperature programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). XRD data showed that only metallic Au phase existed in the catalysts, and the size of gold particles played a crucial role in the catalytic conversion of toluene. The catalytic activity of Au/CeO2 was related to the interaction between gold particles and supports, and the capability of gold particles to weaken the surface Ce-O bonds adjacent to Au atoms. This interaction enhanced the reactivity of the CeO2 surface capping oxygen which was involved in volatile organic compounds oxidation.

Terminal alkynes, under Au-catalyzed conditions, react with aromatic aldehyde diethyl acetals, affording propargylation products through C O bond addition. Furthermore, AuPPh 3 Cl/AgOTf-catalyzed three-component reaction of aldehydes, alkynes, and triethyl orthoformate is developed. Gold alkynilides are supposed to be reactive intermediates in these reactions.

Volatile organic compounds (VOCs) are toxic and contribute significantly to the formation of the photochemical smog, which has remarkable impact to the air quality; therefore, the research on the removal of VOCs has attracted increasing interests during the last decade. This review covers the recent developments in catalytic combustion of VOCs over non-noble metal catalysts including mixed metal oxide catalysts, perovskite catalysts and Au-containing catalysts. The effect of water vapor, coke formation and the effect of supports on the catalytic combustion process will be discussed. The concept of an adsorption/catalytic combustion dual functional system is introduced and several examples of such systems are evaluated. To develop efficient and cost effective VOC removal technologies, further research in catalytic combustion needs to develop novel non-noble metal catalysts and adsorbents, and improve the understanding of catalytic mechanisms involved.

A series of MnO 2 /ZrO 2 mixed oxides were prepared in reverse microemulsions for NOx adsorption and abatement. The results show that the amount of NOx adsorbed was increased with increasing MnO 2 content in various MnO 2 /ZrO 2 samples. The maximum uptake value of NOx was 27.66 mg NOx/g adsorbent on the 40% Mn–Zr sample at 200 °C with NOx initial adsorption rate as 2.63 mg/(g adsorbent min). TPD results show that the complete desorption of NOx was easily obtained by heating the sample to 450 °C, and the temperature for the complete desorption can be further decreased to 210 °C by adding carbon monoxide into the argon desorption streams. Furthermore, water vapor was found to reduce NOx adsorption capacity because of its stronger competitive adsorption with NOx species. It is noteworthy that a small amount of sulfur dioxide could significantly increase the initial rate of NOx adsorption although it slightly decreased the NOx adsorption capacity.

Catalytic combustion of toluene on Cu-Mn/MCM-41 catalyst was performed in tubular flow reactor operated at atmospheric pressure. The effect of catalyst pre-treatment temperatures on the catalytic activity and stability was investigated. Some reaction variables, such as inlet concentration of toluene and oxygen, reaction temperatures and space velocities were varied over wide ranges, and the influence of different reaction conditions on toluene conversion was discussed. It is showed that the catalytic activity was significantly affected by calcination temperatures between 300 and 800 °C, and oxygen concentration, toluene concentration and space velocity are all key experimental factors to optimize the toluene combustion activities. The objective of this study was to investigate catalytic properties of Cu-Mn/MCM-41 catalysts prepared at different calcination temperatures, in order to obtain additional information to prepare an efficient and highly active catalyst at low temperature.