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The wetting behavior of glass coatings on samarium-cobalt alloys with different roughness at elevated temperatures in air was investigated by a sessile drop method. The wetting properties were analyzed through several parameters, including apparent contact angle, height and diameter of a glass cylinder on the samarium-cobalt alloy, determined by using a high temperature microscope. The morphology evolution of the glass coating was observed by using a scanning electron microscope. The results show that the glass cylinder contracts initially, and then swells followed by wetting and spreading on the samarium-cobalt alloy substrate. This process is explained by the role of air and the increase of capillary number. The dependence of apparent contact angle on surface roughness is related to interface reaction. It is concluded that the surface roughness firstly increases the contact angle, but then promotes wetting due to the wetting transition changing from the Cassie−Baxter state to the Wenzel state in the non-reactive wetting range. The surface roughness hinders the spreading of the glass melt due to the interface reaction between glass and samarium-cobalt alloys in the reactive wetting range.

Porous SiC ceramic membrane supports are widely employed in a wide variety of high-temperature applications, such as hot flue gas filtration, porous burners and molten metal filters. Herein, SiC supports, with a porosity of ~37%, were prepared by using low-temperature bonding techniques and the influence of different bonding phases, such as mullite, cordierite and glass, on ambient-temperature flexural strength, hot modulus of rupture (HMOR), thermal shock resistance and oxidation resistance were systematically investigated. The results reveal that the glass-bonded SiC (GBSC) support exhibited the highest ambient-temperature flexural strength of 33.6 MPa, whereas the flexural strength of mullite-bonded SiC (MBSC) and cordierite-bonded SiC (CBSC) supports ranged from 22 to 25 MPa. However, the presence of glass phase deteriorated the high-temperature properties of the support. MBSC support rendered superior mechanical strength at high temperature and self-strengthening in a certain temperature range, such as HMOR improved 47.5% at 900 °C, but HMOR of glass-bonded support was only 57.4% of the ambient-temperature strength. Moreover, MBSC and CBSC supports exhibited better thermal shock resistance than GBSC supports and the critical temperature difference of water quenching for MBSC supports was ~200 °C higher than GBSC supports. In addition, MBSC support rendered superior oxidation resistance and exhibited a weight gain rate of ~0.1% at 1150 °C for 24 h, which is 54.4% and 42.2% lower than CBSC and GBSC supports, respectively.

Ginsenoside Rh2 is one of rare panaxidiols extracted from

In recent years, superhydrophilic and underwater superoleophobic membranes have shown promising results in advanced oil/water separation. However, these membranes still have some drawbacks, like tedious preparation process and instability, which hinder their application in oil/water separation. Accordingly, the development of a facile approach to prepare superhydrophilic membranes with excellent oil/water separation performance is still coveted. Here, a copper mesh decorated with cauliflower-like nickel (Cu mesh@CF-Ni) is synthesized via a facile one-step electrodeposition method. Due to the surface polar -OH and -O-Ni-F groups of the Ni(OH)2/NiO x F y shell of the cauliflower-like nickel (CF-Ni), this Cu mesh@CF-Ni displays superhydrophilic and underwater superoleophobic wettability. The results show that the Cu mesh@CF-Ni has excellent oil/water separation efficiency (higher than 99.2%) and ultrahigh water flux (around 20 L h-1 cm-2). Moreover, it also displays good stability in a 10 wt % NaCl solution and 1 M NaOH solution for oil/water separation. By introducing the CF-Ni with polar Ni(OH)2/NiO x F y components onto the surface of the materials via a simple electrodeposition method, the materials will acquire the capability to not only achieve oil/water separation but also realize many other applications, like self-cleaning, underwater bubble manipulation, and fog harvesting.

In order to develop filter material that can be used for high-temperature gas cleaning, porous SiC ceramic membrane support was fabricated by in situ reaction bonding. Pressureless sintering was carried out in the temperature range of 1280–1480 °C in air. Green bodies were formed by uniaxially pressing coarse SiC particles (150–180 μm) as a skeleton, fine SiC particles and ρ-Al2O3 powder as bonding additives, basic magnesium carbonate as sintering aid and polyvinyl alcohol (PVA) as binder. Effects of sintering temperature and ρ-Al2O3 content on mechanical performance and physical properties of porous SiC ceramics were systematically investigated. Results revealed that interconnected pores of support were mainly formed due to the packing of SiC coarse particles. Mullite (3Al2O3·2SiO2) was formed due to in-situ reaction between cristobalite obtained by SiC surface oxidation and α-Al2O3 converted from ρ-Al2O3 at higher temperatures. SiC particles were strongly bonded by mullite and oxidation-derived SiO2, which resulted in highly porous SiC membrane support with excellent mechanical properties. Open porosity of samples decreased with an increase in sintering temperature and ρ-Al2O3 content. In addition, flexural strength initially increased up to threshold limit, followed by gradual decrease. The sample with 9 wt. % ρ-Al2O3 exhibited the highest flexural strength after sintering at 1430 °C for 3 h. As-prepared SiC support with 9 wt. % ρ-Al2O3 demonstrated flexural strength of 25.1 MPa and air permeability of 4.8 × 10−12 m2. Moreover, as-prepared support exhibited excellent resistance to cyclic thermal shock, which indicates that these supports can be used for high-temperature flue gas cleaning under normal pressure.

To investigate a novel β-glucosidase from Bifidobacterium breve ATCC 15700 (BbBgl) to produce compound K (CK) via ginsenoside F2 by highly selective and efficient hydrolysis of the C-3 glycoside from ginsenoside Rd, the BbBgl gene was cloned and expressed in E. coli BL21. The recombinant BbBgl was purified by Ni-NTA magnetic beads to obtain an enzyme with specific activity of 37 U/mg protein using pNP-Glc as substrate. The enzyme activity was optimized at pH 5.0, 35°C, 2 or 6 U/ml, and its activity was enhanced by Mn2+ significantly. Under the optimal conditions, the half-life of the BbBgl is 180 h, much longer than the characterized β-glycosidases, and the Km and Vmax values are 2.7 mM and 39.8 µmol/mg/min for ginsenoside Rd. Moreover, the enzyme exhibits strong tolerance against high substrate concentration (up to 40 g/l ginsenoside Rd) with a molar biotransformation rate of 96% within 12 h. The good enzymatic properties and gram-scale conversion capacity of BbBgl provide an attractive method for large-scale production of rare ginsenoside CK using a single enzyme or a combination of enzymes.

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.

Solar-thermal water evaporation is a promising technology for pure water production. However, the design of low-cost systems for efficient antifouling solar-thermal water evaporation remains a challenge. Herein, an evaporator based on metal oxy-hydroxides with a hierarchical and hollow structure is rationally designed through material selection and structural engineering. The obtained evaporator possesses good light absorption performance, excellent antifouling property against oil, and enhanced heat localization ability. Consequently, the water evaporation rate reaches as high as 1.65 kg m-2 h-1 with a solar-thermal conversion efficiency up to 82.3% under 1 sun illumination. More importantly, the evaporator exhibits almost identical evaporation performance in oily wastewater and natural seawater due to its superhydrophilicity and underwater superoleophobicity. This work provides a worth-adopted approach to prepare solar-thermal evaporators with high efficiency and anti-oil-fouling property, highlighting the new application of metal oxy-hydroxide-based materials and the importance of a hierarchical and hollow structure for efficient solar-thermal water evaporation.

α-l-arabinofuranosidase is a subfamily of glycosidases involved in the hydrolysis of l-arabinofuranosidic bonds, especially in those of the terminal non-reducing arabinofuranosyl residues of glycosides, from which efficient glycoside hydrolases can be screened for the transformation of ginsenosides. In this study, the ginsenoside Rc-hydrolyzing α-l-arabinofuranosidase gene, BsAbfA, was cloned from Bacilus subtilis, and its codons were optimized for efficient expression in E. coli BL21 (DE3). The recombinant protein BsAbfA fused with an N-terminal His-tag was overexpressed and purified, and then subjected to enzymatic characterization. Site-directed mutagenesis of BsAbfA was performed to verify the catalytic site, and the molecular mechanism of BsAbfA catalyzing ginsenoside Rc was analyzed by molecular docking, using the homology model of sequence alignment with other β-glycosidases. The results show that the purified BsAbfA had a specific activity of 32.6 U/mg. Under optimal conditions (pH 5, 40 °C), the kinetic parameters Km of BsAbfA for pNP-α-Araf and ginsenoside Rc were 0.6 mM and 0.4 mM, while the Kcat/Km were 181.5 s−1 mM−1 and 197.8 s−1 mM−1, respectively. More than 90% of ginsenoside Rc could be transformed by 12 U/mL purified BsAbfA at 40 °C and pH 5 in 24 h. The results of molecular docking and site-directed mutagenesis suggested that the E173 and E292 variants for BsAbfA are important in recognizing ginsenoside Rc effectively, and to make it enter the active pocket to hydrolyze the outer arabinofuranosyl moieties at C20 position. These remarkable properties and the catalytic mechanism of BsAbfA provide a good alternative for the effective biotransformation of the major ginsenoside Rc into Rd.

Micro pin fin arrays have been widely used in electronic cooling, micro reactors, catalyst support, and wettability modification and so on, and a facile way to produce better micro pin fin arrays is demanded. Herein, a simple electrochemical method has been developed to fabricate copper vertical micro dendrite fin arrays (Cu-VMDFA) with controllable shapes, number density and height. High copper sulphate concentration is one key point to make the dendrite stand vertically. Besides, the applied current should rise at an appropriate rate to ensure the copper dendrite can grow vertically on its own. The Cu-VMDFA can significantly enhance the heat transfer coefficient by approximately twice compared to the plain copper surface. The Cu-VMDFA may be widely used in boiling heat transfer areas such as nuclear power plants, electronic cooling, heat exchangers, and so on.

Janus effect has been studied for emerging materials like Janus membranes, Janus nanoparticles, etc., and the applications including fog collection, oil/water separation, CO 2 removal and stabilization of multiphasic mixtures. However, the Janus effect on oil/water separation is still unclear. Herein, Janus Cu mesh decorated with Ni-NiO/Ni(OH) 2 core-shell nanoparticles is synthesized via selective electrodeposition, in which we keep one side of Cu mesh (Janus A) to be superhydrophilic, while manipulate the wettability of another side (Janus B) from hydrophobic to superhydrophilic. Experimental results indicate that Cu mesh with both-side superhydrophilic shows the superior oil/water separation performance (separation efficiency >99.5%), which is mainly due to its higher water capture percentage as well as larger oil intrusion pressure. Further, we demonstrate the orientation of Janus membranes for oil/water separation, and summarize that the wettability of the upper surface plays a more important role than the lower surface to achieve remarkable performance. Our work provides a clear insight of Janus effect on oil/water separation, it is significative to design high-performance membranes for oil/water separation and many other applications.

The mandarin fish Siniperca chuatsi is a cultured freshwater fish species that is popular in China because of its high market value. With the development of high-density cultural mode in mandarin fish, viral diseases such as Infectious spleen and kidney necrosis virus (ISKNV) are becoming increasingly serious. Stimulator of interferon genes (STING) is a central component in the innate immune response to cytosolic DNA and RNA derived from different pathogens. However, the roles of STING in innate immune response of mandarin fish remain unknown. In the present study, S. chuatsi STING (scSTING)-mediated host immune response against ISKNV infection was investigated. ScSTING transcription level increased remarkably in response to ISKNV infection, LPS, PMA, or poly (I:C) stimulation in mandarin fish fry (MFF-1) cells. Immunofluorescence results showed that scSTING localized majorly in the endoplasmic reticulum. scSTING overexpression remarkably increased the expression levels of scIFN-h, scMx, scISG15, scPKR, scViperin, scIL-1β, scIL-18, and scTNF-α genes. IFN-β-luciferase report assay results showed that the relative expressions of luciferin were remarkably increased in MFF-1 cells. Site mutation of serine (S) on C-terminus of scSTING showed that both S388 and S396 were important for mediated signaling. Furthermore, scSTING overexpression inhibited ISKNV infection, and knockdown of scSTING promoted ISKNV infection, indicating that scSTING could suppress ISKNV infection in MFF-1 cells. These observations suggested that the scSTING played an important role in innate immune against ISKNV infection. Our work would help elucidate the roles of teleost fish STING in innate immunity.

Mandarin fish (Siniperca chuatsi) is a significant cultured species with high added value in China. With the expansion of farming, diseases of mandarin fish such as Infectious spleen and kidney necrosis virus (ISKNV) diseases are becoming more and more serious. Human endogenous retrovirus subfamily H long terminal repeat associating protein 2 (HHLA2) is a type 1 transmembrane molecule with three extracellular Ig domains (IgV-IgC-IgV) and plays important roles in the T cell proliferation and tumorigenesis. The HHLA2-homologues have not been found in virus. In this study, a viral HHLA2 protein encoded by ISKNV ORF069L was identified and the virulence of the deleted ORF069L reconstruction ISKNV strain (ΔORF069L) was investigated. ISKNV ORF069L gene was predicted to encode a 222-amino acids peptide. The bioinformation analysis revealed that ISKNV ORF069L contained an Ig HHLA2 domain and was homologous to vertebrate B7-CD28 family proteins. The recombinant virus strain of ΔORF069L was constructed by homologous recombination technology. The virus titer and growth curves between ISKNV wild type (WT) and ΔORF069L on cellular level showed no significant differences indicating that the ORF069L did not influence the ISKNV replication. The expression levels of immune-related genes (Mx1, IL-1β, IL-8, TNF-a and IgM) were increased in fish infected with ΔORF069L, compared to those in fish infected with ISKNV WT. Furthermore, the lethality caused by ΔORF069L declined by 40% compared with ISKNV WT, indicating that ORF069L was a virulence gene of ISKNV. Most importantly, the protection rate was nearly 100% for fish immunized with ΔORF069L strain. Those results suggested that ΔORF069L could be developed as a potential attenuated vaccine against ISKNV. Our work will be beneficial to promote the development of gene deletion attenuated vaccines for ISKNV disease.

The standard near-silicon liquid (2329kg/m3) is a mixture liquid of tribromopropane and dibromoethane in a certain proportion. This liquid is used to measure the density of single crystal silicon spheres by a static suspension method and the analysis of the difference in the micro density between two silicon spheres. Measuring the difference in the micro-density of the silicon spheres is of great significance for the new definition of the new mass of kilograms. In order to obtain the micro-density difference of the silicon spheres, it is necessary to calculate the static pressure value and the temperature by separately adjusting the singlecrystal silicon spheres to the same suspension state and the compression coefficient of the near-monocrystalline silicon density liquid. Through the adjustment of the same hydrostatic suspension state of a single silica ball in different suspension states, the linear constants measured by the linear model are analyzed to calculate the liquid compression coefficient. For this purpose, a static suspension measuring device for a single crystal silicon ball was designed to maintain the water bath within a range of ±0.1mk within 3 hours, and the position control of the silicon ball was determined by controlling the pressure of the upper computer.

Summary Aquaculture provides important food, nutrition, and income sources for humans. However, aquaculture industry is seriously threatened by viral diseases. Infectious spleen and kidney necrosis virus (ISKNV) disease causes high mortality and economic losses to the fish culture industry in Asia and has been listed as a certifiable disease by the International Epizootic Office. Vaccine development is urgent to control this disease. Here, a gene-deleted live attenuated candidate vaccine (ΔORF022L) against ISKNV with low pathogenicity and high protection was developed. ΔORF022L replicated well in mandarin fish fry-1 cells and showed similar structure with wild-type ISKNV. However, the pathogenicity was significantly lower as 98% of the mandarin fish infected with ΔORF022L survived, whereas all those infected with wild-type ISKNV died. Of importance, 100% of the ΔORF022L-infected fish survived the ISKNV challenge. ΔORF022L induced anti-ISKNV specific antibody response and upregulation of immune-related genes. This work could be beneficial to the control of fish diseases., Graphical abstract, Highlights • ISKNV ORF022L deletion recombinant virus (ΔORF022L) was constructed • ΔORF022L was greatly attenuated and caused only 2% mortality in mandarin fish • ΔORF022L-immunized mandarin fish were 100% protected from ISKNV challenge • ORF022L induced immune-related genes and ISKNV-specific antibody responses, Virology; Aquaculture diseases

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.

Recently, oil/water separation has attracted intensive attention because of frequent crude oil spill accidents and the increasing amount of industrial wastewater. Ti-based materials are nontoxic and environment-friendly for oil/water separation; however, there is little attention focused on this field. In the present work, we introduce, for the first time, surface −O–Ti–F groups onto Ti foam by a simple anodization in a fluorine-containing electrolyte to form a superhydrophilic membrane for oil-in-water emulsion separation, which was proven to be excellent with the assistance of surface nanocavities. The water permeability of anodized Ti foam is elevated by about 10 times as compared to that of the original one, and the oil/water separation efficiency is above 99% with good anticorrosive properties. In addition, this fluorine-induced superhydrophilicity can be applied to metals and semimetals for many other applications such as self-cleaning, surface modification of catalysts, removal of heavy metal ions,...

This study explores the novel 2D heteroatom-doped carbon materials for high performance oxygen reduction reaction (ORR). Our strategy involves the ionization of a nitrogen-rich small molecule to prevent its evaporation and subsequent carbonization of the nonvolatile ionic liquids to achieve simultaneous porosity formation and heteroatoms doping. In this context, a nitrogen rich adenine-based ionic liquid possessing a low melting point at 70 °C is synthesized by mixing of commercial adenine and bis(trifluoromethane sulfonimide) (HNTf2). In virtue of protic acid HNTf2, direct carbonization of an ionic liquid results in enhanced carbon yields compared to that of adenine itself. The as-synthesized NC features a uniform 2D quasi ordered nanosheet structure and high surface areas up to 1027 m2 g−1. The nitrogen contents incorporated within the carbon framework can be varied from 37% to 7% as a result of different thermal treatment temperatures from 600 to 1000 °C. Particularly, both nitrogen and sulfur are homogeneously co-doped within the carbon structure as confirmed by EELS maps. The resulting materials show outstanding electrochemical activity towards ORR in alkaline electrolyte, better than most nitrogen doped carbon materials.

In this work, we investigate the droplet bouncing on the hierarchical branched nanotube (BNT) arrays surface above and below 0 °C. By anodization, we fabricate large-area arrays of BNT with the BNT spacing controlled from adjacent to sparse. We evaluate the influence of the BNT spacing on the droplet bouncing. The adjacently distributed BNT (A-BNT) outperforms the sparsely distributed BNT (S-BNT). We find that the A-BNT can repel up to 3.1 m/s droplet at 20 °C and 2.3 m/s droplet at −18 °C, while the maximum bouncing velocity on the S-BNT is below 2.3 m/s at 20 °C and below 0.9 m/s at −10 °C. For the bouncing on the supercooled A-BNT surface, the droplet bouncing contact time increases as the substrate temperature decreases for the same droplet velocity, while the bouncing contact time decreases as the droplet velocity increases for the same substrate temperature. We discuss the influence of the nanosized air cushion entrapped amid the branched-arms of the BNT on the three-phase contact line on the BNT walls and bouncing performance under supercooled conditions.

Recently, oil/water separation has attracted intensive attention due to the frequent crude oil spill accidents and the increasing amount of industrial wastewater. Thousands of outstanding achievements have been reported on the basis of membranes with superhydrophilicity and underwater superoleophobicity. However, a universal approach combining cheaper reagents with easier operations to fabricate superhydrophilic materials for effective oil/water separation is still a challenge and greatly encouraged. In the present work, we fabricate the superhydrophilic copper mesh decorated with nickel nanoparticles (Ni-NPs) via electrodeposition in fluorine-containing electrolyte. The size of Ni-NPs that consists of a metal Ni core and a polar NiO/Ni(OH)2 shell is about 300 nm; what’s more, the Ni-NPs combine with each other to form treelike nickel crystals by varying the experimental parameters. This optimized mesh exhibits remarkable oil/water separation performance. The oil content in separated water is lower than 3...

Surface energy and roughness are well-known to be the two key factors for fabricating surfaces with superhydrophilicity or superwettability, and thousands of outstanding achievements have been reported on the basis of these two aspects in recent decades. However, for the physical chemistry community, it is still a challenge for making man-made superhydrophilic surface with universal and easy operating. Here, we describe the development of fluorine-induced superhydrophilicity (FIS) method to fabricate superhydrophilic interfaces via oxy-fluoridation process, in which the fluorine atoms are linked to metal or semimetal atoms in the form of −O–M–F (M is metal or semimetal atom), and a superhydrophilic interface can be obtained owing to the strong polarity bond of (semi)metal oxy-fluoride. Simulation results showed that hydrogen bonds are formed between water molecules and oxy-fluoridized (semi)metallic interfaces. The value of this FIS has been demonstrated through the successful surface treatment for Ti, Zn...

To investigate a novel β-glucosidase from

A catalytic kinetic spectrophotometric method, which is based on the catalytic effect of Fe(Ⅲ) on the fading reaction between potassium persulfate(K2S2O8) and methyl red(MR) in the solution of 0.30 mol·L-1 hydrochloric acid, for the determination of trace amounts of Fe(Ⅲ) has been investigated. A novel detection system, Fe(Ⅲ)-HCl-K2S2O8-MR, has been developed. The optimum experimental conditions for the determination of trace amounts of Fe(Ⅲ) were found on the basis of orthogonal test. The kinetics parameters and equation of this fading reaction of MR were studied. Its reaction mechanism was discussed. The results show that there is a good linear relationship between the variation of MR absorbance at the maximum absorption wavelength of 518 nm and the concentration of Fe(Ⅲ) under the optimum experimental conditions: ln(A0/A)=1.334 1+0.001 0, the correlation coefficient is 0.999 1. The kinetic research shows that the reaction order with respect to Fe(Ⅲ) is 1 and the overall fading reaction is a pseudo-first order reaction. The apparent activation energy of the fading reaction of MR is 69.88 kJ·mol-1. Furthermore, the catalytic effects of Fe(Ⅲ) on this fading reaction is confirmed by its reaction mechanism. This novel method for the determination of trace Fe(Ⅲ) has never previously been published so far. Trace amounts of Fe(Ⅲ) can be selectively determined by this catalytic kinetic spectrophotometric method with high precision and accuracy. This method is simple and its reagents used are cheap and available. Its sensitivity is higher than that of conventional spectrophtometry with detection limit of 0.005 mg·L-1. This detection system is stable. This proposed method has been applied to the determination of trace amounts of Fe(Ⅲ) in food and water samples with satisfactory results. Relative standard deviation of the detection results is 1.18%～2.11%. Average recovery rate of the detection results is 98.0%～104.0%.

The nitrogen (N) and phosphorus (P) balance was studied and the eco-economic benefits of N and P were evaluated for the paddy field in a red soil area, under the fertilization treatments of no fertilization (CK), chemical fertilizer (NPK), organic fertilizer (M), and chemical fertilizers combined with organic fertilizers (NPKM, NPM, NKM), based on the long-term experiment started in 1982, to optimize fertilizer application and reduce N and P losses. The results indicated that the slight N surplus (27.10 kg·hm应用始于1982年的长期定位试验,研究了单施化肥、单施有机肥及化肥与有机肥不同配比等处理下红壤区稻田的氮磷平衡,并评价了不同处理的生态经济效益,以期筛选出生态经济效益最优的施肥配比,减少红壤区稻田氮磷损失.结果表明: 不施肥处理(CK)下稻田氮素略有盈余(27.10 kg·hm

The SiC ceramic membrane supports by using four different processes were prepared by extrusion molding process. Shape and distribution of pores in SiC ceramic membrane supports were observed by SEM, Meanwhile the O-ring strength was measured. By analyzing the relationship between pores’ shape, distribution and O-rings strength, the optimal data of apparent porosity and the optimal pores’ shape and distribution was obtained. By means ofusing similar particle sizes, particles modification, controlling drying rate of the green body and controlling the contents of glass phase in neck part between SiC particles formed at the high temperature, the SiC ceramic membrane supports with the O-ring strength greater than 20 MPa were prepared.

In recent years, Cu foam has attracted intensive attention owing to its remarkable performance for oil/water separation. Most research has mainly focused on Cu foam with surfactant decoration, which results in superhydrophobic or even stimuli-responsive membranes. Fabricating Cu foam with intrinsic superhydrophilicity via simple operations still remains a challenge. Herein, we synthesized superhydrophilic and under-water superoleophobic Cu foam that consists of oxy-chloridized hierarchical nanoparticles with metal Cu cores and polar Cu2O/CuO1−x/2Clx shells via the combination of anodization, HCl etching and calcination. This material shows ultrahigh water permeability (5 μl water-droplet permeating within 9 ms). The oil/water separation efficiency of superhydrophilic Cu foam (SCuF) is above 99% with the oil content in separated water lower than 3 ppm. Moreover, the oil/water separation performance of SCuF for repeated use and anti-corrosion is also excellent. To the best of our knowledge, it is the first attempt to synthesize intrinsic superhydrophilic Cu foam for effective oil/water separation. Due to the greatly enhanced specific surface area and active sites, it has potential applications in catalysis, hydrogen evolution processes, electrode materials and many other environmental protection and energy fields.

A new family of two-dimensional topological insulator, hydrogenated monolayer Pb2XY (X = Ga/In, Y = Sb/Bi), has been predicted using first-principles density functional theory. The electronic bulk band gap of the proposed systems can be induced in the presence of a spin-orbit coupling effect and its highest value (0.25 eV) was observed in the hydrogenated monolayer Pb2GaBi, which is suitable for practical application. Our simulation study points out that the nanoribbons derived from this new family harbor gapless edge channels. The non-trivial topological nature was further confirmed by calculating the Z2 topological invariant. These novel systems provide a new platform for topological phenomena observation and spintronic applications.

Through-hole TiO2 nanotube arrays (THTNA) are fabricated successfully by applying a large-voltage pulse (ΔV ≥ 40 V) at the end of anodization, and a mechanism is proposed that the fluoride-rich layer (FRL) between Ti substrate and nanotubes is the key factor for fabricating THTNA. In order to confirm the mechanism, the effects of temperature of voltage pulse on the morphology of the bottom of TiO2 nanotubes are explored. The results show the inner diameter of the bottom became larger with the temperature increasing due to the wall thickness of bottom of TiO2 nanotubes decreased and assisted by the increased fluorine content of the bottom, which is strong evidence for the mechanism proposed. What is more, the inner diameter of the bottom of THTNA can be manipulated via this novel mechanism.

On the basis of analyzing VPN network's flaw, designed and implemented a secure and reliable VPN networking model. The model adopts VPN over HTTP protocol and Kerberos to ensure the secure of identification authentication and data transmission. Finally, the paper gives the main algorithm and workflow of the model's Server and Client. Test results demonstrate that, this model has better performance in Maximum number of connection, throughput of system, data encryption, etc. The model suites to the needs of Network Development, has a very good application prospects on secure transmission of the remote.

ADSL line test in the field of telecommunication is high-strength work. But current testing method has low working efficiency and cannot realize automatic test. In this paper, the wire-plugging test robot system based on machine vision is designed to realize remote test and automatic wire-plugging, and it also can improve work efficiency. Dual-positioning method which based on technologies of color-coded blocks recognition and visual locating is used in this system. Color-coded blocks are recognized to realize socket coarse-positioning, the stepper motors in directions of X-axis and Y-axis are drived to move to nearby the socket quickly. Video-positioning technology is used to realized pinpoint the socket. The stepper motors of X-axis and Y-axis are drived to make a plugging to align a socket after the pinpoint action is realized, and then the motor in the direction of Z-axis is drived to realize wire-plugging action. Plugging is resetted to a safe place after the end of the wire-plugging. Performance tests have improved that this wire-plugging test robot system can realize plug-testing task quickly and accurately, so it is a stable wire-plugging equipment.

Model complex production business contains the attributes of completion time, accuracy, and so on; these factors influence each other; and pursuing the balance of these factors is the core idea of the article. Due to the problems of low accuracy or more completion time which may be caused by the traditional algorithm, the research group proposed the serial reduction algorithm which can achieve higher accuracy under deadline for the business. The algorithm sets the active portion for each task and uses the inverse iterative way to obtain a path that can balance both the completion time and the accuracy. By the case analysis, compared with the traditional unidirectional objective algorithm, serial reduction algorithm can optimize the accuracy under the deadline. Finally, the article analyses the parameters that can affect the algorithm performance; the experiment shows that serial reduction algorithm applied to the workflow is feasible and effective, which has the simple advantage.

In this work, for the first time, we systematically investigate the ballistic transport properties of WSe2 nanoribbons using first-principles methods. Armchair nanoribbons with narrow ribbon width are mostly semiconductive but the zigzag nanoribbons are metallic. Surprisingly, an enhancement in thermoelectric performance is discovered moving from monolayers to nanoribbons, especially armchair ones. The maximum room-temperature thermoelectric figure of merit of 2.2 for an armchair nanoribbon is discovered. This may be contributed to by the effects of the disordered edges, owing to the existence of dangling bonds at the ribbon edge. H-passivation has turned out to be an effective way to stabilize the edge atoms, which enhances the thermodynamic stability of the nanoribbons. In addition, after H-passivation, all of the armchair nanoribbons exhibit semiconductive properties with similar band gaps (∼1.3 eV). Our work provides instructional theoretical evidence for the application of armchair WSe2 nanoribbons as promising thermoelectric materials. The enhancement mechanism of the disordered edge effect can also encourage further exploration to achieve outstanding thermoelectric materials.