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A new polyvinyl alcohol foam gel/MOF-808 detergent was used to study the uranium removal process on the cement surface, and the mechanism was deeply analyzed. Through the mutual verification of XPS, infrared spectrum, XRD and SEM, it is confirmed for the first time that MOF-808 mainly relies on its own Zr-OH and carboxyl groups to remove uranyl ions in foam gel, rather than the carboxyl groups on the ligand. Foam gel combined with MOF-808 can improve the decontamination factor of cement surface by 37.3%, and the maximum removal rate of uranium pollution on cement surface can reach 68.1%. [ABSTRACT FROM AUTHOR]

In this work, a foam gel material based on polyvinyl alcohol were successfully prepared to remove uranium contamination on the surface of stainless steel. The material was tested through infrared spectroscopy and thermogravimetric analysis. The decontamination process of the foam gel on stainless steel surface was analyzed by SEM/EDS and XPS. The results show that the foam gel has good stripping properties, and its decontamination factor for removal of radioactive uranium on stainless steel surfaces could reach 90.9, which seems better than the methods of water washing and wiping. [ABSTRACT FROM AUTHOR]

[Display omitted] • [TBAOH][NA] is combined with Eu3+ to construct a dual-emitting fluoroprobe. • Varying F 615 /F 365 values form a basis for dual-emitting fluoroprobe in HQ assay. • HQ induces fluorescence enhancement of the [TBAOH][NA]/Eu3+ system. • DFT calculations and spectral data unravel the fluorescence-enhancing mechanisms by HQ. • HQ binding triggers higher orbital overlap and easier occurrence of photon transitions. Herein, a dual-emitting fluoroprobe was pioneered for the sensitive and selective detection of hydroquinone (HQ) in environmental waters, which was based on integration of a tailor-made fluorescent ionic liquid ([TBAOH][NA]) with Eu3+ (([TBAOH][NA]/Eu3+). HQ could substantially enhance the 365-nm fluorescence intensity (FI 365) of [TBAOH][NA]/Eu3+, whereas no prominent variation ocurred in FI 615. After HQ binding with [TBAOH][NA], the electronic structure of S1 was completely pi-pi*, and the orbital overlap of the latter was much higher, thereby promoting photon transitions. After some key factors were optimized using a central-composite-design (CCD) approach, this fluroprobe provided a linear response from 0.5 to 100 μM and detection limit of 0.15 μM for HQ assay, which was comparable to analytical performance by conventional HPLC-DAD analysis. Overall, the prominent advantages of as-developed fluoroprobe lie in two aspects: (1) Employing the ratio of two well-resolved emission and significantly differential responses to HQ greatly enhance sensitivity and accuracy through a self-calibration system; and (2) [TBAOH][NA] has not only the superiority of "green solvent" like conventional ionic liquids, but also possesses strong luminescence signal owing to introducing 1-naphathoic acid as an anion into tetrapropylammonium hydroxide. Consequently, this dual-emitting fluoroprobe is endowed with great potential in on-site and outdoor HQ monitoring. [ABSTRACT FROM AUTHOR]

In recent years, chitosan has been used as a common raw material to prepare hydrogels for wastewater treatment. In this work, a series of carboxymethyl chitosan/phytic acid (CMCS-PA) composite hydrogels with various amounts of PA were prepared to remove methyl orange (MO) and Congo red (CR) dyes from aqueous solution. The composite hydrogels with well-defined structure were characterized by different techniques. The experimental results revealed that the hydrogel possessed stable porous structure with more wrinkles on the surface due to the formation of intermolecular hydrogen bonding between CMCS and PA during the in-situ polymerization process. More importantly, the optimal adsorption conditions of CMCS-PA were obtained by changing different adsorption factors: ratio of two molecules and pH. And the CMCS-PA (3:1) composite hydrogel presented great adsorption capacity for MO (13.62 mg/g) and CR (8.49 mg/g) at pH = 7 at room temperature. In addition, the hydrogel also showed great adsorption reusability and stability. This work promotes further development in composite hydrogels design and their applications of wastewater treatment. [Display omitted] • Develop new carboxymethyl chitosan/phytic acid (CMCS-PA) composite hydrogels with various amounts. • Composite hydrogels possess well-defined stable porous wrinkles structure. • Hydrogel show great adsorption reusability and stability. • Potential applications of composites based on chitosan in wastewater treatment. [ABSTRACT FROM AUTHOR]

The effect of Bi-substitution on the dielectric properties of yttrium iron garnet (YIG) was studied in this paper. The Bi-substituted YIG (YIG:Bi) polycrystalline samples, having composition of Y3-xBixFe5O12, were prepared by the solid-state reaction method. x varied from 0 to 1.2. The phase formation and microstructure were performed by X-ray diffraction and scanning electron microscopy, respectively. Ions valency was identified by X-ray photoelectron spectroscopy. The impedance analyzers are used to measure the frequency dependence and the temperature dependence of relative dielectric constant (#x03B5;r) and loss tangent (tan δ). The experimental results show that the Bi-substitution lowers the phase formation and sintering temperature. Electronic carrier concentration drops dramatically due to limitation of ferric valency variation. Hence, #x03B5;r and tan δ decrease with addition of Bi. Dispersion characteristic indicates non-Debye-type dispersion. A maximum of #x03B5;r appears as the temperature rises. [Copyright &y& Elsevier]

Divided aperture (DA) technology enhances the depth and anti-scattering capability in microscopy while slightly off-axis digital holographic microscopy improves the input-plane field of view (FOV) utilisation and optimises the detector measurement bandwidth. In this work, we propose a micro-imaging system utilising these two methods to perform full-field 3D topography measurements without any scanning. The DA eliminates the need for element tilts, pinholes, and gratings to produce an angle between the sample and reference beams. Two π /2-phase-shifted interferograms are obtained with polarising elements in one shot. Experiments are performed to prove the feasibility and validity of the proposed method. • We proposed a slightly off-axis digital holographic microscopy with divided-aperture. • A divided-aperture is used to enhance the anti-scattering capability of the proposed method. • Two π /2 phase-shifted interferograms are obtained with polarising elements in one shot. • Experimental results show the validity of the proposed method. [ABSTRACT FROM AUTHOR]

A magnetotunable left-handed material (LHM) consisting of yttrium iron garnet (YIG) slab and metallic wires has been demonstrated by experiments and simulations. The left-handed passband through the LHM can be dynamically and continuously tuned in a wide frequency region by an applied magnetic field. The tunability of the passband is attributed to that of the negative permeability induced by ferromagnetic resonance in the YIG slab. The authors proposed a convenient means to design tunable LHM based on the ferromagnetic materials as an alternative to tunable split ring resonators. [ABSTRACT FROM AUTHOR]

• We reported an off-axis digital holographic microscopy with divided-aperture. • No element tilt is needed to produce the off-axis angle. • A complete analysis was done for the microscopic imaging system. • Experimental results show the validity of the proposed method. Divided-aperture (DA) microscopy is an imaging method that, in addition, improves the anti-scattering capability. The present state-of-the-art imaging methods have the drawbacks of requirement of scanning or low spatial resolution. In this paper, we propose a DA digital holographic microscopy (DADHM) to enable single shot quantitative phase imaging, which, to our knowledge, is the first-of-its-kind. The proposed system is built using a Linnik-type interferometric module associated with the DA technique. In this method, interestingly, an element tilt is not required to produce an off-axis angle between the sample and reference beams because of the employment of DA. Some analyses and experiments were conducted to validate the efficiency of the proposed method, and the results indicate that a high anti-scattering capability with a mean error of 2.42 nm were achieved by the proposed method. [ABSTRACT FROM AUTHOR]

• An innovative measurement method of multi-point natural gas injection system is proposed. • The structure of nozzle is an important factor affecting the gas injection rate. • Increasing the injection pressure can inhibit the injection mass increasing. • The direction of the outlet hole has a significant effect on the injection duration. This paper presents an innovative measurement method of injection characteristics for the multi-point injection (MPI) system of the natural gas engine. The gas injection rate of different nozzle structures can be obtained by measuring the change of gas pressure in the measurement chamber. Base on this, the gas injection characteristics and their variations under different nozzle structures were studied. The results show that, with the increase of injection pressure, the beginning injection moment hysteresis and the end injection moment advances. When the energizing time is less than 6 ms, the injection mass decreases with the increase of injection pressure, and the injection pressure becomes the dominant hindering factor affecting the increase of injection mass. Due to the circumferential open-hole injection tube structure can not directly use the axial momentum of the gas flow along the tube, the injection duration is longer than that of the straight-through injection tube structure. [ABSTRACT FROM AUTHOR]

Extended X-ray absorption fine structure (EXAFS) spectroscopic investigation and sequential extraction were utilized to characterize the adsorption form of Cs in soil. The experimental results show that Cs+ mainly adsorbs on the surface of soil samples S1 and S2, which is a type of weak adsorption. Results of sequential extraction experiments can be directly explained with EXAFS spectra of the samples. The chemical index of weathering (CIW) of the soil has a decisive impact on the adsorption form of Cs+. The research results can provide strong support for the study of the adsorption and blocking behavior of cesium ions by the I/S mixed layer structure in soil. [ABSTRACT FROM AUTHOR]

Intrusion detection, as a technology used to monitor abnormal behavior and maintain network security, has attracted many researchers' attention in recent years. Thereinto, association rule mining is one of the mainstream methods to construct intrusion detection systems (IDS). However, the existing association rule algorithms face the challenges of high false positive rate and low detection rate. Meanwhile, too many rules might lead to the uncertainty increase that affects the performance of IDS. In order to tackle the above problems, a modified genetic network programming (GNP) is proposed for class association rule mining. Specifically, based on the property that node connections in the directed graph structure of GNP can be used to construct attribute associations, we propose to introduce information gain into GNP node selection. The most important attributes are thus selected, and the irrelevant attributes are removed before the rule is extracted. Moreover, not only the uncertainty among the class association rules is alleviated and also time consumption is reduced. The extracted rules can be applied to any classifier without affecting the detection performance. Experiment results based on NSL-KDD and KDDCup99 verify the performance of our proposed algorithm. [ABSTRACT FROM AUTHOR]

The construction of special three-dimensional microstructure is becoming an extremely fascinating approach to upgrade the electromagnetic properties of carbon-based microwave absorption materials (MAMs) recently. Herein, we have demonstrated the successful fabrication of a series of carbon nanotubes (CNTs)@Ni/C foams (CNCFs) through two-step pyrolysis processes. It is found that the loading amount of CNTs has an obvious influence on modulating the electromagnetic diameters of CNCFs, and thus effectively tuning their microwave absorption properties. With the relative carbon content of 66.3 wt%, CNCFs-2 exhibits admirable microwave absorption performance, including the effective absorption bandwidth of 5.8 GHz with the absorber thickness of 1.8 mm and the maximum reflection loss intensity of −47.0 dB therein. Electromagnetic analysis reveals that the intrinsic attenuation ability, well-matched characteristic impedance, and multiple reflection effect synergistically work for the excellent reflection loss characteristics of CNCFs-2, which indicates rational microstructure design and appropriate chemical composition regulation are vitally important for the enhancement of microwave absorption performance. We believe these desirable microwave absorption properties can make CNCFs-2 eligible to be a very promising candidate for high-performance MAMs, and this research will provide some inspirations more or less for the development of more advanced carbon-based MAMs in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The core–shell composite was prepared for degradation of chemical warfare agents. • The core–shell catalyst displayed high recovery and good bio-compatibility. • ILs helped catalyst to boost enrichment capacity and catalytic rates. • DFT calculation helped to reveal the catalytic mechanism and degradation pathways. Detoxicating materials of chemical warfare agents (CWAs) and their simulants play a critical role in reducing pollution contamination and environmental renovation. In this work, we present a simple strategy to prepare a core–shell structure Fe 3 O 4 /UiO-66-NH 2 /ILs@mSiO 2 using hydrogen bonding association and electrostatic forces. We performed disinfection studies on dimethyl 4-nitrophenyl phosphate (DMNP) and 2-chloroethyl ethyl sulfide (2-CEES). The synergistic effects of catalytic activations for CWAs, which reduce the electron transport distance and lower the reaction energy barrier, lead to an increase in hydrolysis and Fenton-like reactions efficiency. Eliminationing tests of DMNP and 2-CEES showed that the half-lives of the degradation reactions were 128.36 and 1.12 min, respectively, and the degradation efficiency did not decrease significantly after 4 cycles. This new type of structure could be magnetically separated within 60 s to facilitate material recovery and reuse. Moreover, the presence of a mesoporous silica shell made the catalyst particles to become biocompatible and environmentally friendly. The degradation pathways of the intermediates were revealed based on nuclear magnetic resonance spectroscopy (NMR), gaschromatography-mass spectrometry (GC–MS) and density functional theory (DFT) calculations. The effective combination of catalysts provided a facile strategy for developing multi-effect synergistic catalysts for the elimination of CWAs and other pollutants. [ABSTRACT FROM AUTHOR]

In this study, soil profiles and pore water from Japanese abandoned arsenic-containing chemical weapons (CWs) burial sites in Dunhua, China were analyzed to understand the distribution of arsenic (As) contamination, degradation, and migration processes. Results of As species analysis showed that the As-containing agents underwent degradation with an average rate of 87.55 ± 0.13%, producing inorganic pentavalent arsenic (As5+) and organic arsenic such as 2-chlorovinylarsonic acid (CVAOA), triphenylarsenic (TPA), and phenylarsine oxide (PAO). Organic arsenic pollutants accounted for 1.27–18.20% of soil As. In the vertical profiles, total As concentrations peaked at about 40–60 cm burial depth, and the surface agricultural soil exhibited moderate to heavy contamination level, whereas the contamination level was insignificant below 1 m, reflecting As migration was relatively limited throughout the soil profile. Sequential extraction showed Fe/Al-bound As was the predominant fraction, and poorly-crystalline Fe minerals adsorbed 33.23–73.13% of soil As. Oxygen-susceptible surface soil formed poorly-crystalline Fe3+ minerals, greatly reducing downward migration of arsenic. However, the reduction of oxidizing conditions below 2 m soil depth may promote As activity and require attention. [Display omitted] • Significant arsenic contamination from chemical weapons was concentrated in the top 1 m soil layer. • As-Containing agents underwent degradation with an average rate of 87.55 ± 0.13% in buried soil. • Concentration and sequential extraction procedure analysis indicate weak transport of arsenic through the soil profile. • The arsenic fixation is mainly controlled by poorly-crystalline Fe3+ minerals. [ABSTRACT FROM AUTHOR]

Abstract: Glass/ceramic composite materials based on CaF2–AlF3–SiO2 oxyfluoride glass and silica ceramic filler were prepared. The sintering behavior, phase composition and dielectric property of oxyfluoride glass/silica ceramic composites, as well as its compatibility with Ag electrode, were investigated. The results show that the glass/ceramic composite system can be sintered at 825°C. When the amount of SiO2 increased from 0 to 20wt.%, the shrinkage decreased from 17.0 to 14.5%, and the dielectric constant decreased from 5.9 to 5.4, while the thermal expansion coefficient (20–200°C) increased from 6.0 to 10.1ppm/°C. The sintered samples had low dielectric losses less than 0.002 and high flexural strengths. This novel glass/ceramic composite system exhibits good sintering compatibility with silver paste, which makes it a promising candidate for low temperature co-fired ceramic application. [Copyright &y& Elsevier]

The emissions of volatile organic compounds (VOCs) from two new furniture including footstool and bedside table, were measured in an environmental chamber. Nine VOCs including benzene, toluene, ethylbenzene, m/p-xylene, o-xylene, styrene, n-undecane, and n-butyl acetate were identified and quantified by thermal desorption and gas chromatography. The effect of loading rate (the ratio of the furniture surface area to the chamber volume) on VOCs emissions was investigated. The release of dominant organics differed with the furniture and significant differences were observed at different loading rates. The change of VOCs concentrations showed a good fit with results from a double-exponential decay model. When the loading rate was doubled, the VOCs concentrations of footstool and bedside table increased 1.108–2.096 and 1.116–3.095 times, respectively. Moreover, human health impact due to pollutants released from new furniture at various loading rates was assessed. By simulating VOCs emissions from bedside table in the indoor conditions previously, the maximum value of HI (non-cancer risk hazard index) at high loading rate (3.6 m2/m3) for six pollutants (toluene, ethylbenzene, m/p-xylene, o-xylene and styrene) was 12.8 times higher than the public acceptable value, implying high non-cancer risk. The present work should be valuable for evaluating VOCs emissions and the relevant human health effects from new furniture. [ABSTRACT FROM AUTHOR]

• A sliding segmentation algorithm is proposed to solve the problem of data deficient. • The selected optimal model was used to realize the diagnosis of soybean disease period. • Provide soybean bacterial spot disease leaf data set. • It provides a reference for the identification of the development process of other crop leaf diseases. Soybean bacterial spot disease is a predominant disease that impairs the quality and yield of soybean produce. In order to minimize production losses to the greatest extent possible, rapid detection and identification of disease progression stages are crucial. However, the conventional techniques used for identifying bacterial spot disease exhibit limitations in terms of providing real-time and objective analysis for dynamically identifying significant differences in the disease manifestation. In the present study, a novel sliding segmentation method was proposed for solving the problem of insufficient data volume, which can diagnose soybean disease stages in a timely and accurate manner, take measures to reduce the impact of diseases on soybeans, and solve the problem of difficulty in obtaining disease datasets. Further, a convolutional neural network (CNN) based image recognition method for soybean leaves at different disease stages was proposed. Different depth learning classical network models were used for transfer learning, and the characteristics of soybean leaf spots in different stages and the differences between diseased leaves and normal leaves were considered. The focus of the experiment was on optimizing a network model by adjusting three factors: the optimization algorithm, epoch number, and batch size number. The aim was to enhance the recognition accuracy of the model. The experimental results show that the optimal network model was based on Swin Transformer, with an optimization algorithm of SGD, epoch, and batch size of 200 and 8, respectively. In the experiment, the optimal model achieved an accuracy of 99.64 % in identifying soybean leaf disease stages. The model can accurately identify soybean leaf diseases at different stages, meet practical production needs, prevent pesticide misuse, reduce yield losses caused by soybean leaf diseases, provide a reference for identifying the development process of leaf diseases, and also provide theoretical support for the establishment of soybean disease warning systems. [ABSTRACT FROM AUTHOR]

Fe/BaFeO 2.5 laminated composite particles were successfully prepared by hydrogen-thermal reducing BaFe 12 O 19 particles. The average diameter of Fe/BaFeO 2.5 composite particles is about 1 μm and the lamellar thickness is about 100 nm. The effective permittivity and permeability of Fe/BaFeO 2.5 laminated composite particles were measured and EMA performance was evaluated. Compared with Fe particles with a similar diameter, the permeability of Fe/BaFeO 2.5 composite particles is remarkably improved by the induction of insulator BaFeO 2.5 phase. Due to the unique 2-dimension shape characteristic, ε′ and μ′ of Fe/BaFeO 2.5 laminated composite particles is obviously higher than that of Fe/BaFeO 2.5 composite particles without lamellar structure. EMA performance of coating containing Fe/BaFeO 2.5 laminated composite particles as fillers is excellent, and a maximum reflection loss ( RL max ) up to −29.94 dB was achieved in a coating of 1.36 mm. Meanwhile, the operation frequency band of coating containing Fe/BaFeO 2.5 laminated composite particles as fillers covers completely X-band and Ku-band, which considerably wider than most of reported EMA coatings. [ABSTRACT FROM AUTHOR]

Understanding the adsorption behavior of radiocesium (RCs) in natural soils is crucial for remediation and evaluation of radioactive contaminated sites. In this study, we investigated the adsorption behavior of Cs(I) onto natural soils collected in Beijing by batch adsorption experiments and sequential extraction. A multi-site adsorption model was built to quantitatively analyze the adsorption capacities of soil clay minerals and predict of Cs(I) adsorption ratio of different adsorption sites. Linear programming calculations show that illite/smectite (I/S) mixture and illite(I) are the mainly clay mineral composition. Batch adsorption experiment results show that soils adsorption of Cesium ions is an exothermic process, and the order of influence of competitive cations on the competitive adsorption strength of Cs(I) is:K+>Mg2+≈Ca2+>Na+. HA (Humic Acid)has little effect on soil adsorption. SEM-EDS analysis shows that Cs+ is mainly distributed on the surface (PS) of soil particles. Based on the above results, the adsorption of Cs(I) onto clay minerals in soils is well predicts in both linear programming calculations and a multi-site adsorption model. The multi-site adsorption model can quantitatively describe and predict the adsorption behavior of Cs(I) on different clay sites in the soils. Frayed edge sites (FES) in the soil can effectively fix trace RCs. The higher concentration of cesium ions is mainly adsorbed on the PS and TIIS. Sequential extraction experiment further proved the adsorption form of cesium in soil under trace and high concentration conditions. [Display omitted] • Linear programming was used to quantify the adsorption of Cs(I) onto soils. • Illite and illite/smectite dominate the adsorption of Cs(I) onto natural soils. • A multi-site adsorption model was built to analyze the adsorption capacities. • Cs(I) adsorption ratio of adsorption sites were calculated and proved. [ABSTRACT FROM AUTHOR]

Background: In the acute respiratory distress syndrome (ARDS), lung-protective ventilation strategies combine the delivery of small tidal volumes (VT) with sufficient positive end-expiratory pressure (PEEP). However, an optimal approach guiding the setting of PEEP has not been defined. Monitoring volumetric capnography is useful to detect changes in lung aeration. Objectives: The aim of this study was to determine whether volumetric capnography may be a useful method to determine the optimal PEEP in ARDS. Methods: In 8 lung-lavaged piglets, PEEP was reduced from 20 to 4 cm H2O in steps of 4 cm H2O every 10 min followed by full lung recruitment. Volumetric capnography, respiratory mechanics, blood gas analysis, hemodynamic data and whole-lung computed tomography scans were obtained at each PEEP level. Results: After lung recruitment, end-expiratory lung volume progressively decreased from 1,160 ± 273 ml at PEEP 20 cm H2O to 314 ± 86 ml at PEEP 4 cm H2O. The ratio of alveolar dead space (VDalv) to alveolar VT (VTalv) and the phase III slope of volumetric capnography (SIII) reached a minimum at PEEP 16 cm H2O. At this PEEP level, overaerated lung regions were significantly reduced, nonaerated lung regions did not increase, and partial pressure of oxygen in arterial blood/fraction of inspired oxygen (P/F) and static respiratory system compliance (Crs) reached a maximum. At PEEP levels <16 cm H2O, nonaerated lung regions significantly increased, P/F and Crs deteriorated, and VDalv/VTalv and SIII began to increase. Conclusions: In this surfactant-depleted model, PEEP at the lowest VDalv/VTalv and SIII allows an optimal balance between lung overinflation and collapse. Hence, volumetric capnography is a useful bedside approach to identify the optimal PEEP. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A tunable isotropic negative effective permeability is experimentally demonstrated in a three-dimensional (3D) dielectric composite consisting of dielectric ceramic cube arrays by temperature changing. It shows that a strong subwavelength magnetic resonance can be excited in dielectric cubes corresponding to the first Mie resonance mode and can be continuously and reversibly adjusted from 13.65 to 19.28 GHz with the temperature changing from -15 to 35 °C. Accordingly, negative permeability can be performed in the frequency range of about 6 GHz by adjusting the temperature. It provides a convenient route to design adaptive metamaterials and 3D invisible cloak. [ABSTRACT FROM AUTHOR]