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A 3D core shell nanoarchitecture with a shell of low coordinated bismuth nanosheets on a core of Cu nanowires was developed, which presents a large current density (>150 mA cm−2) with a high HCOOH selectivity (>90%).

It is a significant challenge to combine a large pseudocapacitive material with conductive honeycomb-like carbon frameworks for long-term stable supercapacitors. Herein, hierarchical composite materials are manufactured by using biomass carbon, ZIF-67, and a mild pore former (Ni(CH3COO)2) to generate alloy-type CoNi3 nanoparticles planted into conductive honeycomb-like carbon frameworks (C@ZIF-67-T). Meanwhile, the effect of carbonization temperature on the honeycomb-like pore size and the structure of composite materials is systematically investigated. As the honeycomb-like carbon skeleton structure guarantees good ionic and electronic conductivities and a large contact area, whereas the alloy nanoparticles provide a rich redox reaction for Faradaic capacitance. Therefore, the as-obtained C@ZIF-67–600 electrode presents a remarkable specific capacitance of 1044.8 F · g−1 at 1.0 A · g−1 and an ultra-long cycling stability with 30,000 cycles at 5.0 A · g−1 in a three-electrode system. In addition, the assembled C@ZIF-67–600//activated carbon asymmetrical supercapacitor exhibit a high specific capacitance of 274.4F · g−1 at 1.0 A · g−1 and a long-term stable lifespan with a capacitance retention of 87% after 20,000 cycles at 5.0 A · g−1. Besides, the asymmetrical supercapacitor also presents a maximum energy density of 85.13 Wh · kg−1 at a power density of 750 W · kg−1. Such superior electrochemical performance demonstrate that the designed electrode material provides a promising energy storage application.

As one of the key stable crops to feed half of the world's population, how rice cropping system affects honey bee health regarding pesticide exposure and forage availability is under investigated. We predicted honey bees were stressed by high pesticide exposure and forage dearth in monoculture rice systems. Providing access to natural habitats is a typical approach to mitigate the negative impact of intensive agriculture on honey bees. We aimed to determine if bee colonies located in landscapes with more cover of forest habitat would collect more forage and be exposed to less pesticides. We selected beekeeping locations in rice dominated landscapes (as control), mosaic landscapes of rice and medium woodland (MW) cover, and landscapes of high woodland (HW) cover, respectively, in July when rice starts bloom and pesticides are commonly used. Colonies were inspected at a biweekly frequency from July to October with population growth and forage (nectar and pollen) availability estimated. Pollen and bees were collected in middle August for pesticide exposure analysis. We did not observe enhancement in forage availability and reduction in pesticide exposure in landscapes with increased forest habitat (i.e., MW or HW cover), and all colonies failed in the end. Other natural habitats that can supplement flower shortage periods in forest can be considered for supporting bee health. Our results suggest that forest should be carefully assessed for being incorporated into beekeeping management or pollinator conservation when forest phenology can be a factor to affect its impact as a natural habitat.

The current domestic and foreign research on azide polymers such as glycidyl azide polymers (GAP) mainly focuses on the design, synthesis, modification, and performance of elastomers; it is difficult to prepare the GAP/NC (nitrocellulose) blends, and they have poor mechanical properties. Here, we developed a green and safe strategy for the blending and compounding of azide binder and NC by blending the emulsion with NC in water and demulsifying. Considering the structural characteristics of GAP, a novel energetic aqueous GAP-E (energetic elastomer) emulsion was prepared by anionic self-emulsion polymerization using 2,2-dimethylol propionic acid as the hydrophilic chain extender, 1,4-butanediol as the chain extender, and triethylamine as a neutralizer. Furthermore, the GAP-E emulsion/triethylene glycol dinitrate/nitrocellulose blends (GAP-E/TEGN/NC) with different proportions were prepared in aqueous phase by the precipitation method. The related properties of the emulsion were studied by gel permeation chromatography, Fourier transform infrared, universal material testing machine, dynamic mechanical analyzer, thermogravimetric analysis, and scanning electron microscopy (SEM). Our results indicated the emulsion exhibited good stability with the number average molecular weight of 76,600. The GAP-E film showed a tensile strength of 17.8 MPa, elongation at break of 415%, glass transition temperature of −28.5 °C, and initial degradation temperature of 242 °C. The GAP-E emulsion and TEGN/NC can be blended in the aqueous phase by the demulsification method to prepare a homogeneous GAP-E/TEGN/NC blend. Fourier transform infrared spectroscopy (FTIR) showed that there was a certain hydrogen bond interaction between GAP-E and TEGN/NC molecules, which was conducive to the improvement of the mechanical properties. The results of SEM indicated that GAP-E could obviously soften the rigid fiber structure of TEGN/GN, and the blends were well mixed with good interfacial compatibility between the GAP-E (5%) and TEGN/NC. When the mass fraction of GAP-E was 5%, the tensile strength and the elongation at break of the blend reached up to 32.1 MPa and 54.4%, which were improved by 33 and 46% compared to those of the TEGN/NC blend system, respectively. The transition temperature remained at −21.6 °C with obvious enhancement on the mechanical properties.

It is a significant challenge to combine a large pseudocapacitive material with conductive honeycomb-like carbon frameworks for long-term stable supercapacitors. Herein, hierarchical composite materials are manufactured by using biomass carbon, ZIF-67, and a mild pore former (Ni(CH

Euodia ruticarpa is a medicinal plant recorded in in Chinese Pharmacopeia. Here we report on the complete chloroplast genome sequence of Euodia ruticarpa. The chloroplast genome is 158,762 bp in size and includes two inverted repeat regions of 54,230 bp, which is separated by a large single-copy region of 86,267 bp and a small single copy region of 18,265 bp. A total of 131 genes were predicted, including 37 tRNA, 8 rRNA, and 86 protein-coding genes. Phylogenetic analysis placed Euodia ruticarpa under the family Rutaceae.

The demand for energy storage equipment in the information age era is becoming increasingly scarce, but manganese-based metal oxides with large potential windows and multivalent states were developed and used as high-performance electrode materials for energy storage. MnO2 array grow on the carbon sphere as the precursor and then obtain multi-types and hierarchical of manganese metal oxides through gradient carbonization. The surface crystal phase changes with temperature, and the electrochemical performance shows obvious imparity. In addition, the carbon spheres gradually disappear with increasing temperature forming a hollow shell structure, which is conducive to sufficient contact between electrolyte and electrode material. It found that the annealing temperature can change the surface oxide morphology of MnO2/C, and it can know that the temperature promotes the conversion of MnO2 to Mn2O3 and Mn3O4. Based on the oxides of different crystal phases, the electrochemical properties are more distinctive due to their different structures. The rod-like nanoarray Mn2O3/C composites derived from annealing the precursors at 600 °C show high specific capacity and rate performance under a very large potential window of 0~1.2 V (show a remarkable specific capacitance of 277.0 F·g−1 at a current density of 1.0 A·g−1). Considering practical application, the as-assembles Mn2O3/C//Na2SO4//Mn2O3/C symmetrical supercapacitors device exhibits a maximum energy density of 80.35 Wh·kg−1 at a power density of 500 W·kg−1, which can be applied promising storage materials for information age.

Tough and transparent polyurethane networks with self-healing capability at mild temperature conditions were successfully prepared in a 1-pot procedure. The self-healing ability of synthesized polyurethane comes from the covalent disulfide metathesis and non-covalent H-bonding. The mechanical testing indicates that disulfide metathesis reforms the covalent bonds on a longer time scale, while H-bonding gives rise to a healing efficiency of around 46% in the early healing processing. The compromise between mechanical performance and healing capability is reached by tailoring the concentration of disulfide. The tensile strength of the sample with 100% self-heal efficiency can get to 5.01 MPa, which can be explained by higher mobility of polymer chain under ambient temperature from creep testing.

Ag loaded mesoporous silica-embedded TiO2 nanocomposites were successfully synthesized via two different routes, including one-pot solvothermal method and solvothermal-chemical reduction method, both using Titanium (IV) n-butoxide (Ti(OC4H9)4) as a precursor, formic acid as a solvent and reducing agent, silver nitrate as a silver source and tetraethyl silicate (TEOS) as a stabilizer. The transmission electron microscopic (TEM) images showed that silica-embedded anatase TiO2 sample exhibited approximately rhombic shape and Ag nanoparticles could be embedded into the nanocomposites or deposited on the surface with high dispersion. The N2 adsorption-desorption isotherms indicated that the silica-embedded anatase TiO2 had obvious mesoporous structure with a BET specific surface area of 203.5 m2·g-1. All Ag loaded silica-embedded TiO2 composites showed a higher photocatalytic H2-generation activity from water splitting under simulative solar light irradiation than that of TiO2 products. The maximum H2 production rate (6.10 mmol·h-1·g-1) was obtained over 2% Ag/silica-embedded TiO2 nanocomposites (2% Ag/MST) prepared by solvothermal-chemical reduction method, which was 20 times that achieved on the silica-embedded TiO2 sample. The enhanced photocatalytic H2-evolution activity of Ag loaded mesoporous silica-embedded TiO2 nanocomposites can be attributed to the multi-function of surface Ag co-catalyst, mesoporous structure, and embedding of silica.

The main purpose of this research is to improve the clustering accuracy of mixed attributes data. Therefore, glowworm swarm optimisation (GSO) algorithm is introduced into K-prototypes algorithm to...

MoO3 nanobelts were prepared by a one-step hydrothermal method and then assembled with aluminum nanoparticles using polyvinylpyrrolidone as a binder. The physicochemical properties of the as-prepared samples were carefully characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis/differential scanning calorimetry, and drop weight impact test. The results showed that the T onset of Mo-Al-0, Mo-Al-1, Mo-Al-2, and Fe-Al-0 are 474.8°C, 484.2°C, 478.5°C, and 514.8°C, respectively, which are 66.0°C, 56.6°C, 62.3°C, and 26.0°C lower than that of pure Al-NPs (540.8°C). The total exothermic heat of self-assembled MoO3/Al during DSC test is about 2626.9 J/g, which is 229.6, 420.8, and 11.1 J/g higher than that of Al/commercial MoO3, Al/hydrothermal MoO3, and Al/referenced Fe2O3. Furthermore, the high exothermic self-assembled MoO3/Al thermite is totally insensitive to impact.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a virus susceptible to antibody dependent enhancement, causing reproductive failures in sows and preweaning mortality of piglets. Modified-live virus (MLV) vaccines are used to control PRRS in swine herds. However, immunized sows and piglets often generate variable antibody levels. This study aimed to detect significant genes and pathways involved in antibody responsiveness of pregnant sows and their offspring post-PRRSV vaccination. RNA sequencing was conducted on peripheral blood-mononuclear cells (PBMCs), which were isolated from pregnant sows and their piglets with high (HA), median (MA), and low (LA) PRRS antibody levels following vaccination. 401 differentially expressed genes (DEGs) were identified in three comparisons (HA versus MA, HA versus LA, and MA versus LA) of sow PBMCs. Two novel pathways (complement and coagulation cascade pathway; and epithelial cell signaling in H. pylori infection pathway) revealed by DEGs in HA versus LA and MA versus LA were involved in chemotactic and proinflammatory responses. TNF-α, CCL4, and NFKBIA genes displayed the same expression trends in subsequent generation post-PRRS-MLV vaccination. Findings of the study suggest that two pathways and TNF-α, CCL4, and NFKBIA could be considered as key pathways and potential candidate genes for PRRSV vaccine responsiveness, respectively.

A pollen-like porous Fe2O3/Al thermite was prepared by a templated method, with aluminium nanoparticles (Al-NPs) embedded in the porous channels. The thermite prepared by reduced pressure released the largest exothermic heat during DSC testing period compared with Fe2O3/Al thermites prepared by ultrasonic mixing and physical mixing. The exothermic heats in the range of 773 K to 1273 K are 3742.3 J g−1, 2279.0 J g−1, 1981.1 J g−1, and 2621.0 J g−1 for pollen-like Fe2O3/Al by reduced pressure, pollen-like Fe2O3/Al by ultrasonic mixing, pollen-like Fe2O3/Al by physical mixing, and commercial Fe2O3/Al by ultrasonic mixing, respectively. The reactivity between Fe2O3 and Al-NPs was efficiently improved, corresponding to its enlarged contact surface area between Al-NPs and the porous pollen-like Fe2O3, and the reduced pre-combustion sintering. Furthermore, pollen-like Fe2O3/Al has good compatibility with both RDX and HMX and it is not compatible with Cl-20 and GAP.

In the usage control of information resources with access control matrix as the core idea, rights are generally permanently endowed to the access subject. Based on the idea of temporary authorization, the usage control strategy for information resources based on UCONABC model is studied and subject reliability is introduced into the UCONABC (usage control authorizations, obligations, conditions) model as the decision-making factor of authorization in the usage control of information resources. Through analysis on typical structural relations among subjects, the evaluation method of subject reliability based on subject relational distance and subject attribute is designed; and on this basis, a new usage control scheme for information resources is constructed.

Mixed micellar electrokinetic chromatography with laser-induced fluorescence detection has been used for analysis of the catecholamines norepinephrine, epinephrine, and dopamine. The fluorescent reagent 5-(4,6-dichloro-s-triazin-2-ylamino)fluorescein was used to label the three compounds. The reaction rate increased with increasing alcohol concentration in the derivatization buffer. Under the optimum conditions the derivatization reaction was complete within 10 min. The separation was performed with 40 mM sodium cholate, 30 mM sodium dodecyl sulfate, 30 mM sodium borate (pH 9.6), and acetonitrile 8.0% (v/v) as running buffer. The applied potential was 25 kV and the capillary temperature was 25 °C. The detection limits for norepinephrine, epinephrine, and dopamine were 3.3, 0.25, and 1.26 nM. The method was successfully applied to monitoring of these catecholamines in human urine. Recovery of the three analytes ranged from 93.2 to 105.8%.

Dense flat membranes of sulfonated polyimides (SPIs) were prepared from 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTDA) and aromatic diamines of 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane disulfonic acid, benzidine-2,2′-disulfonic acid, 4,4′-diaminodiphenylether-3,3′-disulfonic acid and 9,9′-bis(4-aminophenyl)fluorene. The SPI membranes were pyrolyzed at a relatively low-temperature of 450 °C for 1.5 h at a nitrogen flow. During the pyrolysis, the SO3H groups decomposed without substantial cleavage of the polyimide backbone. The pyrolytic membranes had the interesting intermixed properties of toughness and good flexibility as in polymer membranes and high gas permeability with reasonably high selectivity as in carbon molecular sieve membranes. The gas permeability for the pyrolytic membranes seems to be controlled by the sulfonic acid group content in the precursor polyimides, the relaxation of the polymer chains during the pyrolysis and the gas permeation level of the precursor membranes. Decomposition of SO3H groups induced microvoids, which are considered to remain to some extent as larger-size free volume holes in the polymer matrix, resulting in the higher diffusivity to gas with larger diameter. The pyrolytic membranes showed the higher permeability of C3H6 and/or the higher selectivity of C3H6/C3H8 than the 6FDA-polyimide membranes which have defined the upper bound line.

Effects of pyrolysis and preparation conditions on the gas permeation properties of pyrolytic membranes derived from sulfonated phenolic resin were investigated. Pyrolysis temperature, dip-coating conditions and coating/pyrolysis (C/P) cycle had significant influence on the gas permeation properties of pyrolytic membranes. Membrane obtained under optimum preparation conditions exhibited O 2 permeance of 30 GPU and ideal O 2 /N 2 separation factor of 12 at 35 °C, which are comparable to the O 2 /N 2 separation performances of carbon molecular sieve (CMS) membranes on the upper-bound line in the plots of permeance versus selectivity. N 2 adsorption and desorption at 77 K suggested that the pore structures of CMS membranes pyrolyzed around 500 °C seemed to be made up of interconnected pores with different size and shape.

A thermosetting phenolic resin with a pendant sulfonic acid group was prepared by reacting a resol-type phenolic resin (PF) with a Novalak-type sulfonated phenolic resin (SPF). Large amounts of gaseous molecules with similar and small size such as H2O and SO2 evolved in the range of 110 and 350 °C during the pyrolysis of this thermosetting phenolic resin (PF/SPF). Highly permeable carbon molecular sieve (CMS) membranes were obtained by pyrolysis of PF/SPF(45/55) precursor membranes which were dip-coated on porous alumina tubes. For example, the membrane pyrolyzed at 500 °C for 1.5 h displayed H2, CO2, and O2 permeances of 1950, 800, and 240 [GPU (gas permeation units) = 10-6 cm3(STP)·s-1·cm-2·cmHg-1], respectively, and ideal H2/CH4, CO2/CH4, and O2/N2 separation factors of 65, 27, and 5.2 at 35 °C and 1 atm, respectively. Sulfonic acid groups linked to thermostable polymer chains might act as “bonded templates” and showed attractive potential in the preparation of CMS membranes.

Electropolymerized film of metal ethylenebis(salicylideneiminate) [(M(salen), M=Co, Fe, Cu and Mn] was utilized as material for development of an electrochemical sensor for the determination of NO in solution. The sensors based on polymeric M(salen) were prepared by a means of electropolymerization with cyclic voltammetry (CV) in acetonitrile solution containing M(salen) for optimized cycles. Nafion was used as a second coating to the sensors and differential pulse amperometry (DPA) was used as a subsequent determination technique. The resulted sensors were found to display good activity toward the oxidation of NO with low detection limits and a good linear relationship between the current and NO concentration. The mechanism of the polymeric M(salen) modified sensor was preliminarily studied by using a technique of quantum chemistry and proposed to be a three-dimensional catalytic pattern by conjugation of the electron of the NO molecule and the polymeric M(salen).

RECENTLY, great attention has been paid to the physical and chemical properties of atomic andsemiconductor clusters. On the properties of AlB n atomic cluster, experimental studieshave been reported, yet theoretical studies have not been seen.Aluminium borides (AlB n ) have been widely used to change the fiber strength in mechanical engineering and to adjust the...

Based on the specific elements in terms of process area, project, practice and relevant methodologies, which were adopted from Capability Maturity Model Integration(CMMI), this paper studied feasible appraisal program that combined the CMMI implementation cycle model into entire software process, therefore, the index system and measurement model in measuring the quality of software developing process were built and the barrier of CMMI model could only be used in enterprise CMMI certification was broken down.

This experiment was conducted to investigate the effects of dietary ratios of n-6:n-3 polyunsaturated fatty acids (PUFA) on the performance of lactating sows and their piglets. Thirty pregnant Landrace sows were assigned to one of three treatments from d 108 of gestation until weaning (26–29 d) and were fed diets containing different ratios of n-6:n-3 PUFA including 3:1, 9:1 and 13:1. The effects on sow and litter production traits were examined together with an assessment of sow body condition. No differences were detected among the treatments for the daily feed intake of sows or changes in sow weight and back-fat levels during lactation (P > 0.05). Litter size at d 14 and d 21 were tended to increase in 3:1 treatment compared with 9:1 and 13:1 treatments (P P P < 0.01). The effects of different ratios of n-6:n-3 PUFA in sow diets on colostrum, milk, and piglet plasma immunoglobulin concentrations are studied. No difference was observed among treatments in the concentrations of IgM, and IgA in colostrum (P > 0.05). A great significant difference for IgG concentration was observed among 3 group in colostrum. A great significant difference for IgA, and IgM (P P P In summary, the current study demonstrated that altering the ratio of n-6:n-3 PUFA in lactating sow diet had an effect on the immune component including immunoglobulin and cytokines, and it tended to increase the litter average daily gain and improve the immune status of piglets when dietary ratio of n-6:n-3 PUFA was 9:1.

A method for the indirect determination of arginine by graphite furnace atomic absorption spectrometry after preconcentration on a Nafion chemically modified tungsten coil is described. The mechanism is discussed. In HCl solution (pH 3.5), the exchange competition between protonated arginine and Cu 2+ on the Nafion film causes a decrease in the amount of Cu 2+ binding to the Nafion film, resulting in a decrease in the absorption signal of Cu 2+ being measured. A linear relationship between the decrease in absorbance and the concentration of arginine is obtained in the range 3.1 × 10 −8 -2.5 × 10 −7 mol 1 −1 . The relative standard deviation for ten parallel determinations is 2.3%. The detection limit is 1.3 × 10 −8 mol 1 −1 . The results for the content of arginine determined in cephradine injection are satisfactory.

Polyimides were prepared from dianhydride with planar structure and Cardo-type or bulky-group-containing [-C(CF3)2-] diamines. Dense and flexibile flat membranes produced by the pyrolysis at relatively low temperature displayed high separation performance for C3H6/C3H8 and CO2/N2 gas pairs.