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Zinc-ion capacitors (ZICs) are newly emerged hybrid devices consisting of battery-type anodes and capacitive-type cathodes, which are expected to meet high energy-power demands. The performance of ZICs is usually limited by the poor performance of porous carbon cathodes. In this work, heteroatom doped, hierarchically porous carbons were developed using a straightforward and scalable one-step method. The specific surface areas and pore size distributions could be tailored by adjusting the precursor ratio and their effects on the electrochemical performance were investigated. The fabricated ZICs showed the highest capacity of 168.4 mAh g−1 with an energy density of 131.9 Wh kg−1 at 0.5 A g−1. The highest power density of 30.8 kW kg−1 could be achieved at 40 A g−1, allowing a fast complete discharging of a ZIC device in 6.6 s. Furthermore, the cycling stability of the device was investigated, registering nearly 100% capacity retention and almost 100% Coulombic efficiency after 12,000 cycles at 10 A g−1. The morphology and impedance tests measured at different charge and discharge conditions shed some light on the mechanism of the hybrid capacitive behavior. The proposed carbon cathodes offer great potential for ZICs in energy storage applications.

Capacitive deionization (CDI) is an effective method for desalination of brackish water to alleviate the global freshwater crisis. Obtaining high desalination capacity is the primary focus of this field. Based on electrical double layer (EDL) theory, current research is mainly devoted to increasing the specific surface area of electrode materials, however, the NaCl adsorption capacity is typically limited to the range of 10 - 20 mg g−1. In this work, we propose a new design paradigm of using a vertical-aligned nanotubular structure for CDI. This design allows ions to be temporarily held inside the electrodes like ships docked in a harbor (ion-docking effect, IDE) due to the greatly diminished water flow inside the tubes, thus enhancing the desalination capacity. As a result, the obtained CDI device based on vertical-aligned nanotubular P-TiO2 arrays shows an ultra-high NaCl adsorption capacity of ~60 mg g−1 within 30 minutes in 0.01 mol L−1 NaCl solution under 1.2 V, corresponding to a rapid average adsorption rate of 2 mg g−1 min−1. Moreover, the adsorption capacity could be further increased up to 121 and 136 mg g−1 under 1.2 and 1.5 V for 2.5 hours adsorption, respectively, but still far from its equilibrium value. Finally, experiments and theoretical simulations are combined to further understand the IDE in CDI. This work highlights the discovery and the utilization of IDE in CDI, and provides new guidance for the design of CDI electrodes and can facilitate the development of CDI technology.

Essential oils are important secondary metabolites, which are mostly synthesized and accumulated in secretory cavities. In this study, the accumulation of essential oil, variation in composition and the pattern of expression of genes related to monoterpene biosynthesis during fruit development were investigated in kumquat peel. The number of cavities per fruit was approximately 2500. The average volumes of cavities were 16.05, 23.13, 32.69, 68.80 and 94.71 nL at 30, 60, 90, 120 and 150 days after flowering (DAF), respectively. During the fruit development, the average volume of the cavities in the peel increased consistently, and the accumulation of essential oil fit a sigmoid curve pattern. Limonene was the most abundant component (67.47–72.98%), followed by myrcene (3.91–4.83%), germacrene-D (1.86–3.00%), linalool (0.48–2.64%) and γ-elemene (1.79–2.12%). The content of compounds associated with disease resistance and pungent odor were reduced (or even disappeared) during fruit ripening. A correlation analysis showed that the expression of DXS2, HDR and IDI were closely related to the accumulation of essential oil in kumquat peel.

Inflammation mediates a variety of physiological and pathological events, prompting an importance of inflammation management for prevention and treatment of inflammatory diseases. This study formulated tripterine (Tri) into selenized phytosomes in an attempt to attenuate its cytotoxicity and potentiate its inflammation-regulating effect with selenium. Tri-loaded phytosomes (Tri-PTs) with selenium modification were prepared by a melting-hydration followed by in situ reduction technique. Then, selenized Tri-PTs (Se@Tri-PTs) were characterized by particle size, entrapment efficiency, and transmission electron microscope. The in vitro drug release and cellular uptake were performed to examine the formulation performance of Se@Tri-PTs. The cytotoxicity and anti-inflammatory efficacy through inhibiting NLRP3 inflammasome activation and pyroptosis were appreciated in murine J774A.1 macrophage cell line, respectively. The resultant Se@Tri-PTs presented a particle size of 125 nm around. Se@Tri-PTs exhibited attenuated cytotoxicity and improved cellular uptake in macrophages compared with free Tri or Tri-PTs. Also, Se@Tri-PTs inhibited the releases of caspase-1p20 and mature IL-1β, resulting in restriction of NLRP3 inflammasome activation that inhibits the formation of GSDMD-NT whereby to initiate pyroptosis. Altogether, our findings suggest that Se@Tri-PTs can inhibit inflammatory response by regulating the NLRP3/caspase-1 pathway, which in turn reduces pyroptosis via suppressing the cleavage of GSDMD.

Terahertz (THz) spectra contain chemical information, along with noise and variable backgrounds. Measurement environmental changes and spectral signal differences caused by changes in the sample state can degrade the accuracy of the calibration models. This problem obviously hinders practical applications of THz spectroscopy. To tackle this problem, a three-dimensional spectrum was first self-constructed and converted into an intensity image. Zernike moments with inherently invariant properties were then used to describe the THz intensity image and extract the invariant features for further analysis. Considering the reconstruction error and computational cost, the highest order of Zernike moments and the most effective moments were selected and applied to multi-classifiers including support vector machines, naive Bayes, and regularized linear discriminant analysis. Experiments used a THz dataset collected from four chemical substances (melamine, tartaric acid, lactose, and glucose) at five thicknesses (1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, and 3.0 mm). The results confirmed the effectiveness of the proposed approach. The obtained results show that compare to traditional absorption spectrum features, Zernike moment features are less sensitive to spectral variations caused by changes in sample status. They have better feature representation ability with lower feature vector dimensions. This suggests that they can be integrated into the design of systems for THz spectral classification to increase the robustness and generalization capability of the classifier.

In order to predict the early failure of organic insulator, Co3O4@TiO2@Y2O3 nanocomposites was prepared and characterized (XRD, SEM, EDS, FTIR, UV–vis–NIR, XPS) to detect decomposition CO gas. A simple experimental platform was built to verify the excellent adsorption, stability, selectivity and repeatability of the composite. Then, the mechanism of adsorption enhancement was analyzed by heterojunction. Aiming at 170 sets of gas sensing data sets, Successive Projections Algorithm (SPA) was used to extract data features, and grey wolf optimization vector machine regression (GWO-SVR) model was established to predict carbon monoxide concentration. The correlation coefficient (RP), root mean square error (RMSEP) and calculation time of prediction set were 99.3025%, 0.0418 and 1.47 s, respectively. Therefore, the combination of the superior properties of a composite sensitive material and the small sample quantitative prediction model is a promising method for gas sensors in the future.

Herein, we report on the double-layer gate dielectric effects on organic phototransistors (OPTs) based on 2,7-dipentyl[1]benzothieno[3,2-b][1]benzothiophene (C5-BTBT)/polyimide (PI) blends as channel materials. The content of C5-BTBT in a blend was varied from 90 to 10 wt.%. We fabricated OPTs with double-layer gate dielectric composed of PVP/pMSSQ (denoted as XD) and SiO2 dielectrics. The introduction of the XD layer enabled shifting of the threshold voltage to more positive values of the gate voltage, eliminated hysteresis in the dark, and suppressed the hysteresis under UV light illumination. In addition to effects of the double-layer gate dielectric, it was found that the best performance of OPTs was achieved with a very low content of C5-BTBT in the blend (20 wt.%). Under UV light intensity of 3 mW cm−2, 20:80 C5-BTBT:PI OPTs exhibited the highest photosensitivity (107) and photoresponsivity (67 A W−1) with negligible hysteresis. Evaluation of the photoresponsivity as a function of light intensity revealed that OPTs maintained the high photosensitivity of 107 even under the weak UV light intensity of 0.11 mW cm−2. The dynamic characteristics of OPTs were affected by the XD dielectric layer, the content of PI and the source-drain voltage. The decay times of the persistent photocurrent (the photo memory) were longer for OPTs with the double-layer gate dielectric, higher content of the PI, and at the low source-drain voltage of −0.1 V. The OPTs have potential application as photo memory elements with low operating source-drain voltage and multilevel programming/controlling of their performance.

Reduction of power consumption of mechanical tilling operation benefits the environment and sustainability of a farming system. Rotary blade is the main tilling part of a handheld tiller, and its shape and parameters directly affect power consumption and performance of a handheld tiller. For purpose of optimization of rotary blade and energy saving for the tilling operation, soil-cutting simulation was performed by means of Smoothed Particle Hydrodynamics (SPH) modelling in this study. Taking cornerite of bending point (X1), alpha angle (X2) and bending angle (X3) as control factors and power consumption (Y) as evaluation index, soil-cutting experiments by simulation were conducted according to Taguchi method, and correctness of the simulation was validated by soil bin test. The effects of those control factors on power consumption were investigated. A regression equation of power consumption in terms of control factors and their interactions was obtained. The response surfaces to power consumption as functions of X1, X2 and X1, X3 were plotted. Results showed that: control factors of X1, X2 and X3 are significant at 0.1% probability level by F test of analysis of variance (ANOVA), with orders of importance as X1, X2 and X3; optimized parameters of the rotary blade are X1 30°, X2 52°, and X3 120°; power consumption of the optimized rotary blade is 0.161 kW, with a 12.40% of power consumption reduction compared with the traditional design.

In this study, the spatial evolution properties of laser filament clusters in turbulent air were evaluated using numerical simulations. Various statistical parameters were calculated, such as the percolation probability, filling factor, and average cluster size. The results indicate that turbulence-induced multi-filamentation can be described as a new phase transition universality class. In addition, during this process, the relationship between the average cluster size and filling factor could be fit by a power function. Our results are valuable for applications involving filamentation that can be influenced by the geometrical features of multiple filaments.

Mechanoresponsive polymers have garnered significant attention in recent years, due to their great potential application in stress/strain sensing and damage warning. Several reviews of mechanochemistry have been published recently. In this review, we mainly focus on the most established mechanophore, spiropyran (SP), from an engineering perspective. We present a workflow for SP mechanochemistry, applications in various polymeric systems and impacting factors, as well as characterization techniques. Current limitations and future research directions are briefly highlighted in the end. This review aims to offer deep insight into polymer mechanochemistry and provide approaches to study other mechanophores using the example of SP mechanochemistry in polymers.

Herein, a facile single-step hydrothermal method is reported for the synthesis of Ni and Zn doped SnO 2 nanomaterials, i.e. nanoparticles and nanosheets. The synthesized pure and doped SnO 2 nanomaterials were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The diffraction planes from the XRD analysis correspond to the tetragonal rutile crystal phase of doped SnO 2 . A slight shift in the diffraction angles for doped SnO 2 nanomaterials as compared to pure SnO 2 confirms the replacement of the Sn 4+ with Ni 2+ and Zn 2+ ions. The SEM analysis revealed that SnO 2 and Ni-doped SnO 2 possess nanoparticle shaped morphologies while the Zn doped SnO 2 exhibited sheet-like structures. The compositions of the pure SnO 2 , Ni and Zn doped SnO 2 nanomaterials were ascertained by XPS studies which confirmed the purity and doping of SnO 2 nanomaterials. Further, gas sensor applications of synthesized Ni and Zn doped SnO 2 nanomaterials were evaluated at different operating temperatures and concentrations of the CO gas. The optimized temperatures for pure SnO 2 and doped SnO 2 nanomaterials based gas sensors were 310 °C and 280 °C, respectively. For an even very low concentration of 50 μL/L, Ni and Zn doped SnO 2 gas sensors showed gas responses of 7.28 and 5.90, respectively at 280 °C. Thus, Ni-doped SnO 2 nanoparticles based gas sensor exhibited better gas response than pure SnO 2 and Zn doped SnO 2 based gas sensors though response and recovery times were comparable with those of Zn doped SnO 2 gas sensor.

The perceptual video coding systems for optimization have been developed on the basis of different attributes of the human visual system. The attention-based coding system is considered as an important part of it. The saliency map method representing the region-of-interest (ROI) from the video signal has become a reliable method due to advances in the computer performance and the visual algorithms. In the present study, we propose a hybrid compression algorithm that uses the deep convolutional neural network to compute the spatial saliency followed by extraction of the temporal saliency from the compressed-domain motion information. The level of uncertainty is calculated to combine to form the video's saliency map. Afterwards, the QP search range is dynamically adjusted in HEVC, and a rate distortion calculation method is proposed to choose the pattern and guide the allocation of bits during the video compression process. Empirical reporting results proved the superiority of the proposed method over the state-of-the-art perceptual coding algorithms in terms of saliency detection and perceptual compression quality.

In the present work, nanostructures of metal-oxide semiconductors (TiO2 and Co3O4) were combined to obtain a novel chemoresistive sensor. The experimental results show that there is a linear relationship between gas flow rate and adsorption response. The adsorption response of the composite can reach 15.993, and has good selectivity, linearity(R2 = 0.96077) and repeatability at the same gas flow (300 sccm) and temperature(140 °C). Besides, based on the first principles, the promotion effect of Co3O4 supported TiO2 on CO adsorption was verified from the electronic properties. The experimental and theoretical indicate that the Co3O4@TiO2 nanocomposites is an excellent carbon monoxide gas sensing material and has a wide application prospect.

In order to solve the threat of SO2 and H2S, decomposition by SF6 circuit breaker to the environment, staff safety and equipment operation, a Fe-doped ZnS nanomaterial adsorbent was proposed. In this paper, the adsorption behavior of Fe-ZnS was studied by the first principles theory. The adsorption ability of Fe-ZnS for the different orientations of SO2 and H2S was analyzed from the density of states, adsorption energy, charge transfer, Charge density difference and electron localization function. The results show that the adsorption ability of Fe-doped ZnS is significantly higher than that of pure ZnS, and the adsorption order of Fe-ZnS for two gases is SO2 (Eads=-3.299 eV,Qt=-0.67e)> H2S(Eads=-2.749 eV, Qt=-0.55e). In addition, the results are verified by the competitive adsorption of mixed gas. Therefore, Fe-ZnS may be a promising gas adsorbent, which can greatly eliminate the influence of two toxic gases on SF6 circuit breakers and play a key role in improving the safe operation of SF6 circuit breakers.

The application of terahertz (THz)-based techniques in biomolecule study is very promising but still in its infancy. In the present work, we employed THz time-domain spectroscopy (THz-TDS) and THz time-domain attenuated total reflection (THz-TD-ATR) spectroscopy to investigate the properties of tyrosine (Tyr) enantiomers (L- and D-Tyr) and racemate (DL-Tyr) in solid state and aqueous solutions, respectively. THz absorption spectra of solid L- and D-Tyr show similar absorption spectra with peaks at 0.95, 1.92, 2.06 and 2.60 THz, which are obviously different from the spectrum of DL-Tyr with peaks at 1.5, 2.15 and 2.40 THz. In contrast, although THz absorption spectra of L-Tyr solution and D-Tyr solution are similar and different from the spectrum of DL-Tyr solution, both of them have no observable peaks. Interestingly, it was found that the solution containing equal amounts of L- and D-Tyr has a similar spectrum as that of DL-Tyr solution, as far as the mass concentrations of the two types of solutions are kept the same. On other hand, solid L-, D- and DL-Tyr were also investigated with infrared spectroscopy and Raman spectroscopy, respectively. The results show that the spectra of L- and D-Tyr can be regarded the same but they are slightly different from the spectrum of DL-Tyr. With the aid of principal component analysis (PCA), the difference between L-/D-Tyr and DL-Tyr can be confirmed without any ambiguity. Overall, this work systematically interrogated and evaluated the performance of THz-based techniques in the detection of the chirality of tyrosine.

The development of doped porous carbon materials has attracted much attention in the application of supercapacitors. This study reports a straightforward one-step method to prepare nitrogen−fluorine dual-doped porous carbon through direct carbonization of commercially available 2-methylimidazole and tetrafluoroterephthalonitrile in the presence of KOH. The obtained porous carbon demonstrated superb specific surface area of more than 2,000 m2 g−1 and high fluorine and nitrogen doping (> 10% in total). The obtained materials were investigated for fabrications of supercapacitive electrodes and devices. The doped carbon registered a specific capacitance of 354.4 F g−1 at 0.5 A g−1, with a capacitance retention of 72% at 10 A g−1 using H2SO4 electrolyte in a three-electrode system. In the cyclic stability test, little capacitance and Coulombic decays were observed after 5,000 cycles at 10 A g−1. An assembled symmetric supercapacitor with a voltage window of 0–1.2 V yielded a specific energy of 7.7 Wh kg−1 at 150 W kg−1 in Na2SO4 electrolyte. This work presents a new protocol for the synthesis of high-performance carbon-based materials for energy-storage applications.

The detection of toxic gas decomposition in gas insulated switchgear is an important technology to predict and judge equipment failure. In this paper, the adsorption model is established by the first principles. It is found that the band gap of Ni-doped ZIF-8 clusters is reduced and the selectivity is enhanced. The key adsorption parameters such as adsorption energy, charge transfer, bond length, bond angle, density of States, charge density difference and electron localization function were calculated and analyzed. The adsorption of SO2, H2S, SOF2 and CF4 was analyzed by Ni-ZIF-8 cluster and overall structure adsorption model, and competitive adsorption was introduced to verify single gas. The calculation results show that ni-zif-8 has the best selective adsorption of SO2, and the order of adsorption priority is SO2 > H2S > SOF2 > CF4. Therefore, it provides a feasible theoretical basis for the design of gas sensor.

In this paper, we synthesized two types of epoxy group containing POSS derivatives: mono and poly Double-Decker Silsesquioxanes (mono DDSQ and poly DDSQ). The performance of epoxy resin with different DDSQ loading ratios was investigated, including curing kinetics, thermal, mechanical and surface properties. Both mono and poly DDSQ significantly improved thermal and mechanical properties of the epoxy thermosets. The mono DDSQ showed more flexible structure and toughened the epoxy resin better, while the branched poly DDSQ exhibited better thermal resistance. In addition, the DDSQ altered surface of the epoxy resin from hydrophilic to hydrophobic.

In the present work, we investigated effects of the dielectric/semiconductor interface modification on the photoelectrical properties of phototransistors comprising a UV responsive semiconductor blend 2,7-dipentyl-[1]benzothieno[2,3-b][1]benzothiophene (C5-BTBT) and a linear unsaturated polyester (L-upe). Using various self-assembly monolayers with different end-groups at the dielectric/semiconductor interface we modulated the drain photocurrent and response times under the UV light illumination of phototransistors. Treatment of the SiO2 dielectric surface with organosilanes led to the variation of the max mobility in the dark 0.10–0.18 cm2 V−1 s−1 and under UV light 0.08–0.50 cm2 V−1 s−1. Interestingly, detailed crystal structure analysis using 2D X-ray diffraction and photoelectrical characterization revealed that mobility in the dark predominantly depends on the alignment of C5-BTBT crystallites at the interface. Under UV light, the mobility increased with the electron withdrawing/donating nature of the SAM end-functional group. Additionally, chemical modification of the SiO2 dielectric surface increased photocurrent relaxation/decay times upon UV light removal while retaining fast response times when exposed to UV light, which enhanced memory properties of fabricated phototransistors (fast UV response = writing and long relaxation = long data storage).

Thermoelectric devices can convert thermal energy directly into electrical energy. The aim of this study was to develop an approach for integrating computer-aided analysis with an optimization method that could be applied to the design and optimization of thermoelectric generators. The optimization framework consisted of a model generator, a direct solver, and a numerical optimizer. The simplified conjugate-gradient method (SCGM) was used to build the optimizer, and the general-purpose finite-element code was used for the direct solver and model generator. This approach was applied to the multi-objective and multi-parameter optimization of geometric thermoelectric generators to design an optimal structure for both a two-stage bismuth-telluride (BiTe)-based and skutterudite-based thermoelectric generator (TEG) module. The leg length and the ratio between the cross-sectional areas (i.e., footprint) of the semiconductor columns and the TEG module were found to significantly affect the TEG performance; hence, all were incorporated into the present optimization study. Multi-objective optimization was used to realize a design that properly balanced the power output and conversion efficiency so that both improved simultaneously.

Spiropyran (SP) mechanophore cross-linker was covalently incorporated into two widely used polyolefins, poly(ethylene-vinyl acetate) (EVA) and poly(ethylene-octene) (EOC), through facile cross-linking by peroxide under hot press. It was found that (1'-(2-(methacryloyloxy)ethyl)-3′,3′ dimethylspiro[chromene-2,2'-indolin]-6-yl)methyl methacrylate (SP3) could not be thermally driven to merocyanine (MC) in polyolefins during high temperature cross-linking, which is superior to other types of SP mechanophores used for polymer processing. The force-induced ring-opening reaction of SP-to-MC was demonstrated on SP3-cross-linked EVA. It was found that increasing the SP content resulted in earlier activation and that more MC was driven from SP at a slower strain rate. When held at constant strain, MC gradually reverted to SP. The mechanoactivation of SP was also investigated for SP3-cross-linked EOC. This work represents the first example of color-changeable polyolefins in response to mechanical force and demonstrates the feasibility of applying mechanophores to widely-used commercial polyolefins for stress sensing.

This paper reports synthesis of the first high internal phase emulsion (HIPE) system with double emulsion (DE) morphology (HIPE-DE). HIPE is a highly concentrated but highly stable emulsion system, which has a dispersed/internal phase fraction over 74vol%. DE represents an emulsion system that hierarchically encapsulates two immiscible phases. The combination of HIPE and DE provides an efficient method for fabrication of complex structures. In this work, HIPE-DE having a water-in-oil-in-water (W/O/W) morphology has been prepared for the first time via a simple one-step emulsification method with poly(2-(diethylamino)ethyl methacrylate) (PDEA) microgel particles as Pickering stabilizer. An oil phase fraction up to 90vol% was achieved by optimizing the microgel concentration in aqueous phase. The mechanism of the DE formation has been elucidated. It was found that while PDEA microgels stabilized the oil droplets in water, small amount protonated DEA monomers acted as surfactant and formed water-containing micelles inside the oil droplets. It was demonstrated that the W/O/W HIPE-DE could be precisely converted into porous polymer structures. With styrene as the oil phase in W/O/W HIPE-DE, porous polystyrene particles were obtained upon polymerization. With dissolved acrylamide as the aqueous phase and toluene as the continuous phase, porous polyacrylamide matrixes were prepared. Elevating temperature required for polymerization did not change the W/O/W HIPE-DE morphologies. This simple approach provides a versatile platform for synthesis of a variety of porous polymer systems.

Copper contamination results in poor stability and limited application of latexes generated using emulsion ATRP. This work describes an electrolysis method, which provides for the removal of copper from such latexes, while preserving colloidal stability and latex particle integrity. Polyacrylate latexes were synthesized via emulsion polymerization with reverse ATRP. The reaction was mediated by CuCl2/4,4-di-(5-nonyl)-2,2′-bipyridine (dNbpy) and stabilized with a combined surfactant system of Brij-98 and a new surfactant-ligand (SL) design, which provides for the capture Cu species residing at the interface of latex particles. It is shown that >98% of the residual Cu was removed after 14-h of electrolysis at a voltage of 3 V, and >99% Cu removal was achieved after 7-h treatment at 9 V. For comparison, a Cu removal of

Foam flow through processing equipment can seriously affect the structure of the foam and its quality attributes. In the design of a foam formulation and its flow system, it is therefore important to consider the possible implications on the end-of-pipe structure of the foam to ensure preservation of product quality. We study the flow through a straight pipe with and without the presence of a narrow orifice plate and, hence, the dynamic stability of wet food relevant foams of fine texture and high static stability generated from complex formulations of viscous shear-thinning fluids in a continuous multi rotor-stator device. The effects of fluid formulation, gas-liquid ratio, rotor speed and constriction aperture size are investigated. Constricted foam flow can cause important transformations in the foam due to significant bubble coalescence and loss of air volume resulting in much coarser and much less stable foam. Increased surfactant content, liquid viscosity and rotor speed reduce bubble coalescence and help preserve foam structure.

Soil acidification is a worldwide problem and adoption of acid-tolerant rootstocks is an essential strategy to face this challenge in order to maintain the production of citrus. In the present study, seedlings of five genotypes of citrus rootstocks including KPJ-020 (Citrus depressa Hayata ‘Shiikuwasha’), KPJ-007 (C. reticulata Blanco), KPJ-010 (C. daoxinensis Blanco), Carrizo (C. sinensis × Poncirus trifoliata) and ZYXC (C. junos Siebold Tanaka) were used as testing materials and subjected to 10, 30 and 60 days treatment with nutrient solutions at pH2.5, 3.5, 4.5 and 6.0 (control), respectively, to evaluate their tolerance to acidic stress. Symptoms of leaf damage, relative electrical conductivity (REC), the content of chlorophyll, soluble sugar (SS), soluble protein, proline, malondialdehyde (MDA), and the activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in the leaves were examined at different period time of treatment. Acidic stress caused symptoms of chlorosis on leaves due to reduced content of chlorophyll pigments. Analysis of physiological and biochemical parameters indicated that both physiological and biochemical processes of plants were significantly affected by acidic stress. Lower pH decreased the accumulation of N, P, K, Ca, Mg and B, but increased the accumulation of S, Fe, Zn, Mn and Cu. Principal component analysis based on the nine parameters was performed in order to comprehensively evaluate the acidic tolerance of rootstocks. The degree of acid tolerance significant varied within the rootstocks. ZYXC and KPJ-020 showed better tolerance than other rootstocks. Analysis of orthogonal experiment results revealed that the influence of the factors in the treatment to acidic tolerance varied among different rootstocks. In KPJ-020, the duration of treatment was the main factor affecting the tolerance, but the strength of acidic stress was the main factor determining the tolerance of ZYXC, as well as other three rootstocks. This suggested that the mechanisms of acidic tolerance were probably different between the two tolerant genotypes of rootstocks of ZYXC and KJP-020. The former possesses the tolerance by maintaining the capability to uptake mineral nutrients under acidic stress, while the latter has better ability to adapt to lower pH conditions.

The ease of peeling is an important fruit quality trait for fresh-eating citrus, particularly mandarins. In the practice of hand peeling of citrus fruits, both the peel-pulp adherence and peel resistance to penetration are relevant to the ease of peeling. In this study, we first elaborated an easy apparatus that facilitated precise quantification of peel-pulp adherence and peel resistance to penetration. Through measuring mandarins, oranges, pummelos and lemons that each included 10 varieties, the ascending order of the peel-pulp adherence was mandarin

The protein content in soybeans is one of the important indicators to measure the quality of soybeans. This paper studied the feasibility of terahertz (THz) spectroscopy and chemometrics for quantitative detection of protein content in soybeans. Firstly, the THz absorption spectra of samples were processed by eight pre-processing. Secondly, through the calibration set, partial least squares regression (PLS), principal component analysis-radial basis function neural network (PCA-RBFNN) and artificial bee colony algorithm support vector regression (ABC-SVR) were used to establish quantitative detection models of soybean protein. Samples from the prediction set were used to verify the models. Finally, the related coefficient of prediction set (Rp), root mean square error of prediction set (RMSEP) and relative standard deviation (RSD) of ABC-SVR model were respectively 0.9659, 1.3085% and 3.5334%. The experimental results show that after proper pre-processing, THz spectroscopy and chemometrics can be used to quickly detect the protein content in soybeans.

The decomposition gas of SF6 circuit breaker adsorbed on MOF-505 analogue had been analyzed and studied in this paper by using the first principles of density functional theory (DFT) to analyze adsorption mechanism. The adsorption structures of organic ligands and metal sites were established and optimized. Through analyzing the adsorption energy, adsorption distance difference, charge transfer, density of states, Charge density difference and electron localization function, the results show that organic ligands and metal sites have excellent adsorption effect on H2S and SO2, belonging to chemical adsorbent, and the adsorption capacity is far greater than that of SF6. The MOF-505 analogue will be a potential adsorbent for the fault recovery of SF6 circuit breaker.