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ZnO ceramics should have good mechanical properties to meet their applications in semiconductor industry. Based on experiments and the first principles, the effect of Mo doping on the microstructure and the mechanical properties of ZnO and AZO ceramics were studied, and the model of the effect of Mo doping on ZnO crystal defects was established. The results of the structures and fracture-surface morphology of different systems show that doping Mo atoms is beneficial for ZnO and AZO ceramics to eliminate the lattice defects, promote the grain growth and reduce the porosity at low doping concentration. However, when the doping concentration is too high, the new phase of Zn3Mo2O9 is formed and precipitated in 4MZO crystal. Correspondingly, the lattice distorted of doping systems is so serious that hinders the growth of grains and further affects the mechanical properties. Then, the bilinear stress-strain (σ-e) relationship was constructed by nanoindentation and finite element method. The results of mechanical properties by nanoindentation experiment and the first-principles simulation show that doping Mo can improve the hardness, elastic modulus, initial yield stress, plastic tangent modulus and creep resistance of ZnO and AZO ceramics. In particular, the mechanical properties of MZO ceramics are significantly improved because of the formation of Mo–O covalent bond between Mo6+ and O2−. In addition, it is worth noting that due to the synergistic and compensation effect of Al and Mo co-doped atoms, which is favor for reducing the lattice strain, improving the resistance to lattice deformation and forming the covalence of MAZO system, the mechanical properties of MAZO ceramics are increased remarkably.

Myrothecol A (1), a rare 10,13-cyclo macrocyclic trichothecene, and two known compounds (2 and 3) were isolated from the fungus Myrothecium roridum, which was obtained from the gut of a locust Atractomorpha sinensis Bolivar. Their structures and absolute configurations were determined through HRESIMS (high resolution electrospray ionization mass spectroscopy), NMR (nuclear magnetic resonance), ECD (electronic circular dichroism), and Mo2(OCOCH3)4-induced ECD experiments. Compounds 1−3 exhibited potent cytotoxic effects against human tumor cell lines MGC803 and NCI-H1975 with IC50 values between 68 nM and 28.72 μM. These results suggested that macrocyclic trichothecenes could be a kind of potential precursors for the anti-cancer drug development.

2D Fe/Co and N/B codoped mesoporous carbon nanosheets (FeCo/NB-Cs) were ingeniously synthesized to strategically boost kinetics of oxygen reduction/evolution reaction (ORR/OER) by a facile but advanced route. The FeCo/NB-Cs display ultrahigh specific surface area (SSA) of 1584 m2 g−1 and total pore volume (TPV) of 1.21 cm3 g−1, higher than most of currently reported M-N-C catalysts. Delightfully, FeCo/NB-Cs also exhibit obvious mesoporous properties via easy tailoring of H3BO3 dopant. Without doubt, FeCo/NB-Cs exhibit remarkable ORR/OER catalytic activity (total overpotential, △E = 0.653 V), exceeding most of reported heterogeneous-doped carbon materials. Meanwhile, the FeCo/NB-Cs based zinc-air batteries display high power density and perfect charge-discharge stability. More significantly, theoretical calculation reveals that greatly enhanced catalytic activity of FeCo/NB-Cs originates from higher HOMO (highest occupied molecular orbitals) energy, higher DOS (density of states) and weakened O2 adsorption strength owing to synergetic contribution of Fe/Co and N/B dopants. Consequently, this work not only provides a facile but advanced avenue to rationally design heterogenous-doped carbon nanosheets with high SSA and large TPV but also reveals the insight understanding for synergetic contribution of different active species.

Photocatalytic ozonation is an attractive advanced oxidation process for wastewater treatment, but highly active catalysts with strong response to visible light are urgently needed to push forward its practical application. In this study, a hierarchical biomimetic monoclinic bismuth vanadate (BiVO4) with leaves morphology was synthesized by a hydrothermal method, and employed as catalyst for oxalic acid and penicillin degradation in photocatalytic ozonation. The results show that the organics degradation was more efficient using leaves shaped BiVO4 as catalyst than the bulk shaped one in photocatalytic ozonation and the synergy index is ranged from 2.8 to 3.3, indicating a superior positive synergistic effect between photocatalysis and ozonation. The higher activity of the leaves shaped BiVO4 was probably attributed to the distinctive biomimetic morphology and preferable band structure with more negative CB potential. Mechanism studies suggested that the main reactive species were h+ and OH for the degradation of persistent oxalic acid in photocatalytic ozonation. In addition, the effect of ozone concentration and inorganic ions and reusability of the material were also intensively investigated.

The structural stability, electronic structure, and superconductivity of cubic sodium hexaboride NaB6 are calculated from first principles using density functional theory (DFT). The calculations of phonon dispersion spectra, formation energy, and elastic constants indicate that the cubic NaB6 is dynamically, thermodynamically, and mechanically stable, respectively. The cubic NaB6 has lower formation energy compared with the experimentally synthesized KB6. The calculated band structure and PDOS demonstrate the metallicity of NaB6. The superconducting transition temperatures at ambient pressure for NaB6 and KB6 are predicted to be 15.7 K with λ = 0.60 and 14.6 K with λ = 0.57, respectively.

Most of the freshwater aquaculture fish species in the world, especially cyprinid fishes, contain intermuscular bones (IBs). IBs are often small and sharp, and they consequently limit how the fish can be processed, cause injury or trauma if lodged in consumers' throat or mouth and therefore affect the appeal of the fish to many consumers. In order to assess the possibility of decreasing IBs counts through selective breeding, this study evaluated the heritability of the number of IBs in blunt snout bream (Megalobrama amblycephala), which is one major aquaculture species in China. A total of 758 offsprings from 69 parents were genotyped at nine polymorphic microsatellite loci, and then 672 offspring from 213 full-sib families (33 female and 25 male breeders) were used for genetic parameter estimates. IBs were carefully teased from different poached sections of the flesh and counted. Heritability was estimated using an animal model. The results showed that IB number ranged between 84 and 146 per individual in the test population, with an average of 118 IBs. Coefficient of variation in IB number (CV) in ventral sections (13.63%) was substantially higher in comparison to dorsal sections (6.60%). The genetic correlation of IB number between the two sections was significantly positive and high (0.93) (P

Cr3C2-NiCr coating was fabricated by high velocity oxygen fuel (HVOF) spraying, and its hydrophobic properties under mechanical wear and after exposure to high temperatures were investigated. The as-received coating shows excellent hydrophobicity with a water contact angle of 151 ± 1°. The coating also presents good mechanical wear resistance to retain water contact angle of 150° over a 3.0 m abrasion length under a pressure of 4 kPa against diamond disk (#1500). Further enhancement of the non-wettability of the coating after annealing is achieved by surface modification using epoxy resin, where the secondary nanoscale-rough structure introduced by the resin fiber plays a critical role. Possible mechanisms for the excellent hydrophobicity under abrasion and after high-temperature exposure are discussed. Results of this work demonstrate the hydrophobic cermet coatings prepared by HVOF in combination with surface modification may have practical application in harsh working conditions.

Sex-specific molecular markers provide significant molecular basis for sex control breeding biotechnologies to produce mono-sex fish population in aquaculture breeding programs. “Xianfeng No. 2”, a new hybrid of Megalobrama amblycephala (M. amblycephala) (♀) × Ancherythroculter nigrocauda (A. nigrocauda) (♂), with the females growing faster than males, is one of an important aquaculture fish species in China. In order to avoid genetic contamination impact on the ecological environment, maintain gene purity and improve the economic value, it is greatly important to cultivate all-female strains. In this study, artificially induced gynogenesis was performed in the hybrid females and it was found that all progenies were females. Then, we used 2b-RAD-seq to screen the sex-specific markers of the hybrid species. Nine male-specific tags were firstly identified by the sequencing, and then two male-specific tags were screened and successfully validated by PCR amplification in both hybrid and paternal A. nigrocauda populations. Furthermore, one male-specific molecular marker ref57660–1 (326 bp) was validated by RNA-seq and quantitative interpretation from the gene expression level, which indicated the reliability of the marker. Together with the results of all females from gynogenesis population and the identified male-specific markers, it is suggested that this hybrid species is female homogametic (XX) with sex determination mechanism being XX/XY type. The identified sex-specific markers are of great value to improve the efficiency of all-male/all-female breeding practices for this hybird species as well as for paternal A. nigrocauda.

In this paper, a series of fully sp2-hybrid three-dimensional boron nitride nanoribbons (3D-BNNRs) polymorphs entirely composed of hexagonal rings is described herein. The 3D-BNNRs can be considered as connected BNNRs with different widths. All the predicted structures are thermodynamically metastable with 0.111–0.281 eV per BN unit higher than hBN. The elastic constants and phonon dispersion calculations show the 3D-BNNRs are mechanically and dynamically stable. The 3D-BNNRs are semiconductors, which are independent of the width of BNNRs. Tensile strength calculations show the 3D-BNNRs are very strong in the BNNRs-like plane, comparable to graphene and BNNRs. Moreover, under uniaxial strains, the 3D-BNNRs are very stretchable, and can hold more deformation along the direction perpendicular to BNNRs motif than in other directions, although the ideal strengths are lower than those in-plane direction.

Three novel sp2-sp3 hybridized BC6N phases with a sandwich structure, including a type of orthorhombic BC6N (o-BC6N) and two types of tetragonal BC6N (t-BC6N-1 and t-BC6N-2), are investigated through first principles calculations. The structural stabilities are confirmed by the calculated elastic constants and phonon dispersions. Calculated electronic band structures, density of states (DOS), and partial DOS show that the o-BC6N, t-BC6N-1, and t-BC6N-2 crystals may possess the metallicity with the conducting electrons from the p orbits of sp2-hybridized C atoms. Calculations of electron orbits indicate that the electrons in o-BC6N and t-BC6N-1 structures can conduct through the π bonds along the orientation parallel to the [1 0 0] and [0 1 0] directions in different layers. Moreover, the electrons in t-BC6N-2 structure can conduct along the orientation parallel to the [1 1 0] and [ 1 ¯ 1 0] directions in different layers. The behavior of the linear electron conductivity in the layer and vertical direction of conduction between the adjacent layers imply that the three kinds of crystals have potential applications in the field-effect devices. Calculation results using the semi-empirical microscopic model show that o-BC6N, t-BC6N-1, and t-BC6N-2 are potential superhard materials with Vickers hardness of 52.4, 45.3, and 40.1 GPa, respectively.

Carbon can be metal, semiconductor or insulator depending on its structures, and its conductivity can be one-dimensional (1D), 2D, and 3D correspondingly. Boron Nitride (BN) is isoelectronic to carbon, but one prominent difference between the two systems is their electronic properties. For many years, the synthesized and predicted BN allotropes were always insulators, irrespective of their structures. In this paper, with the help of structures searching based on first-principles calculations, a sp 2 / sp 3 -hybridized metallic monoclinic 3D BN ( M -BN) structure is proposed. M -BN can be viewed as puckered hexagonal-BN (h-BN) layers bucked by partial sp 3 B N bonds. The electronic property analysis revealed that the metallicity of M -BN is attributed to the delocalized 2 p electrons of the sp 2 B and N atoms. The metallic B atoms and N atoms are aligns in two arrays along a 1D axial direction, resulting in the unusual 1D dual-threaded conduction in 3D M -BN structure. The enthalpy calculation have revealed that M -BN is the most energetically favorable structure among the predicted metallic BN structures so far, and it might be obtained via compressing layered h-BN precursor theoretically. Due to the 3D strong framework, M -BN has an estimated Vickers Hardness of 33.7 GPa, indicating it is a potential hard material with novel 1D conduction.

Effect of interface undulation on the high-temperature oxidation behaviors of grit-blasted and coated zircaloys in pressurized water was investigated. The grit-blasted and the coated zircaloy substrates present significantly higher corrosion rate than the as-received flat substrate during the early stage of exposure. Numerical analysis suggests the interface undulation results in redistribution of the oxide growth stress of zircaloy, as well as varying the local stress concentration, which induces initiation of cracks and therefore increases the corrosion rate of zircaloy. Propagation of cracks along the interface drives delamination of the protective coating. Results of this work not only promote understanding of the coating/substrate interface evolution in high-temperature pressurized water, but also provide a guide to design corrosion-resistant zirconium alloys and/or coatings for fuel cladding.

We constructed a series of novel 3D-BC2N structures that can be obtained by compressing well-mixed carbon nanotube and boron nitride nanotube arrays. Sequential theoretical calculations indicated a variety of electronic and mechanical properties, such as superhardness, tunable band gap, and ductility, for these novel 3D-BC2N polymorphs. In specific, 3D (6,6)-Ⅱ, 3D (4,4)-Ⅱ, 3D (8,8), 3D (6,6)-Ⅰ and 3D (8,0) are energetically more favorable than previously proposed diamond-like β-BC2N; the hardness of 3D (6,6)-Ⅱ can reach a remarkably high value of 72 GPa; 3D (6,0) and 3D (8,0) are direct gap superhard phases; and 3D (10,0) has a semimetallic nature.

Carbon allotropes with distinct sp , sp 2 , and sp 3 hybridization possess various different properties. Here, a novel all- sp 3 hybridized tetragonal carbon, namely the P carbon, was predicted by the evolutionary particle swarm structural search. It demonstrated a low density among all- sp 3 carbons, due to the corresponding distinctive microporous structure. P carbon is thermodynamically stable than the known C 60 and could be formed through the single-walled carbon nanotubes (SWCNTs) compression. P carbon is a direct bandgap semiconductor displaying a strong and superhard nature. The unique combination of electrical and mechanical properties constitutes P carbon a potential superhard material for semiconductor industrial fields.

Bacterial hemorrhagic disease caused by Aeromonas hydrophila is one of the harmful bacterial diseases for aquaculture. The aim of this study was to evaluate the genetic parameters for resistance to A. hydrophila in blunt snout bream Megalobrama amblycephala. A total of 834 individuals at one-year old from 27 families were experimentally infected with A. hydrophila. During five days duration of the challenge test, deaths peaked at the second day after infection and average mortality over the whole population was 83.93% (family averages ranging from 97.22% to 22.22%). The heritability of A. hydrophila resistance (dead or alive at peak mortality, day 2, under an animal model) under cross-sectional linear (LIN), cross-sectional threshold models (THRp and THRI) was quite different, ranging from zero to 0.33. Compared with the phenotypic correlation coefficient, the genetic correlation coefficient between disease resistance and growth related traits, was relatively high for all genetic parameters. Genetic correlations of resistance to A. hydrophila with body height (0.63), body length (0.65) and body weight (0.60) were significant (P 0.05). These results provide the first report for heritability of resistance to A. hydrophila in M. amblycephala, and correlation with three growth related traits (body height, body length and body weight) could efficiently facilitate indirect selection of M. amblycephala with high A. hydrophila resistance.

Carbon possesses various allotropes with diverse electronic properties from insulation to conduction due to the sp, sp2, and sp3 bonding types. Here, a new sp2-sp3 carbon allotrope, called C48, is proposed. C48 presents a lilac-like structure with a cage-like center and four petal-like tubes around, and can be formed through compressing single-walled carbon nanotubes. C48 is not only strong and hard in 3D but also has unexpected 1D conduction along eight divided linear pathways in the unit cell. This multithreaded 1D conduction in 3D framework is peculiar in carbon materials, and would be helpful to design singular electronic nanodevices.

In this study, four sp3 hybrid boron nitride polymorphs were proposed based on first principles calculations. The calculation results indicated that, at ambient conditions, four polymorphs are stable based on the criteria of dynamic and mechanical stability. At ambient conditions, they are thermodynamically metastable than h-BN, but more stable under high pressure conditions. In these four boron nitride phases, atoms are assembled in cubic symmetry, which are all sp3 hybrid cubic diamond-like structures, and the results showed that the Vickers hardness of them are as hard as c-BN, indicating they are potential superhard materials. Meanwhile, these four structures are considered as wide band gap semiconductor structures with direct band gap. Therefore, these four boron nitride structures have great potential as photovoltaic electronic devices and cutting tools.

This work explored the feasibility of sodium lactate as a novel draw solute to conduct the forward osmosis (FO) process in the field of food processing. As a common low-cost food addictive, sodium lactate is non-toxic and shows high osmotic pressure. Based on this knowledge, the results of this work further revealed the combinative effect of osmotic pressure and viscosity of sodium lactate solution on the FO performance. The effect of draw solution concentration, membrane orientation and temperature on the FO performance were also investigated. The results revealed that a maximal average water flux of 56 LMH was reached during the FO experiments with sodium lactate as draw solute. Taking into account the average water flux and the reverse solute flux, 7.1 M was the optimal concentration of the sodium lactate solution for FO process. The application of such draw solution into the concentration of sugar solution and orange juice then validated its promising performance in terms of efficiency, food quality preservation and membrane regeneration.

AZO, MZO and MAZO, the new photosensitive materials prepared by aluminum or molybdenum doping zinc oxide, has received attention due to its potential as a transparent conductive layer for thin film solar cells. In this present, the effects of Al and Mo doping on the structure, electronic and photoelectric properties of ZnO were studied by means of the first-principles method based on density functional theory (DFT). The results indicated that the doping systems were n-type semiconductor, and the carrier concentration and conductivity of AZO, MZO and MAZO were remarkably improved. More interestingly, compared with Al doping, only small amount of Mo doping concentration could make MZO and MAZO possess higher carrier concentration and conductivity. Furthermore, the investigation results of the optical properties showed that Mo doping deteriorated the optical properties of the transparent conductive films in the visible spectrum. Whilst, the transmittance of AZO deteriorated in the long-wavelength (LW) region of visible spectrum, and ameliorated in the short-wavelength (SW) region. Significantly, MAZO had high transmittance in the whole visible range after Al and Mo co-doping, which means MAZO thin films possessed excellent transparency as well as high conductivity. Investigation results contribute theoretically to the preparation of MAZO transparent conductive films.

In this paper a sp2-/sp3-hybridized cubic N-rich BN phase dubbed as B28N32 is proposed by first-principles calculations. Structurally, B28N32 is constructed by B-N bonds with different lengths, which can be considered as sp3-hybridized cubic BN blocks interlinked by sp2-hybridized N atoms. Notably, B28N32 is energetically metastable at zero pressure, but the calculated formation enthalpies against to hBN and N2 become negative at pressures above 30 GPa, indicating the viability synthesize of this N-rich compound under pressure. The stabilities of B28N32 compound at zero pressure are confirmed by phonon dispersion spectrum and Born stability criteria. Electronic band structure, density of states and electron orbits calculations show the metallic feature of B28N32 is originate from 2p electrons of sp2-hybridized N atoms, and form a unique 3D conductive network in the framework. The theoretical Vickers hardness of B28N32 estimated with two formulas is 55.3 and 40.8 GPa, respectively, which is supposed to superhard material. The proposed B28N32 enriched the B-N system in theoretically, promising in electronic devices.

The technology of doping molybdenum into zinc oxide (ZnO) is an effective method to increase the electron concentration. In this presentation, Mo-doped ZnO (MZO) models with different Mo doping concentrations are constructed to systematically reveal the effect of Mo doping concentration on the photoelectric performance of ZnO. Moreover, the photoelectric performances, such as band structure, electronic conductivity, absorption, reflectivity and transmittance, have been investigated by means of the first-principles method based on density functional theory (DFT). The results indicated that MZO materials are all n-type semiconductors. Both the band gaps and electric conductivities were grown as the Mo doping concentration increased. Furthermore, the absorption and reflectance of the MZO increased, and the transmittance decreased with the increase of Mo doping concentration. Moreover, when the MZO materials are performed as the thin films, the light transmittance of MZO increased as the thickness of the thin films decreased. Especially, in the range of yellow light to red light, the transmittance of MZO was obviously greater than that of ZnO. Accordingly, the conductivity and optical performance of MZO materials are extreme sensitivity to the Mo doping concentration and thin film thickness, and should be optimized. This result provided theoretical guidance for the preparation of Mo-doped ZnO transparent conductive films.

In this paper, a layer-like sp2-/sp3-hybridized orthorhombic phase of B3N5, named as oA-B3N5, is theoretically predicted to be stable at ambient pressure by first-principles calculations. The mechanical and dynamical stability has been confirmed by the elastic constants and phonon frequency curves calculations. The analyses of electronic properties show the metallicity of oA-B3N5 originates from the delocalized 2p electrons of sp2-hybridized N atoms, forming several independent 1D conductive channels, giving the 1D metallicity in 3D framework. Furthermore, the incompressibility of oA-B3N5 exhibits highly anisotropic, and higher axial incompressibility along the N-N bonds direction comparing to the predicted semiconductor C2221-B3N5.

Diamond-like B C compounds exhibit the favorable properties of high hardness and superconductivity. The explorations for novel B C phases are kept on going and it was desirable to explore whether the diamond-like structure can still exist stably or not when the content of boron increases. Herein we predicted a nondiamond-like structure t2-BC took place the lowest energy position of the diamond-like structure, which is completely different from the BCx (x ≥ 2) system. Based on elastic constants and phonon dispersion calculations, the mechanical and dynamic stability of t2-BC were confirmed. Furthermore, hardness and electron–phonon calculations reveal that t2-BC is superhard (Hv = 55.4 GPa) and superconductive with superconducting critical temperature reaching 6.4 K. These results have practical significance for the experimental synthesis of diamond and nondiamond like B C compounds.

A novel and versatile ionothermal synthesis is cleverly proposed to derive two dimensional CoFe/SN-doping and tailor-made open porous carbon nanosheets by inorganic eutectic salts as layered templates. Impressively, as-synthetized open pore structure of CoFe/SN-carbon can be precisely tailored by eutectic salt-templates. 2D CoFe/SN-doping carbon nanosheets (CoFe/SN C) exhibit high specific surface area (1004 m2 g−1) and ultrahigh pore volume (1.54 cm3 g−1). As a result, the 2D CoFe/SN C with ultrahigh meso/macro-porous pore volume (1.25 cm3 g−1) exhibits superior catalytic activity for ORR (E1/2 = 0.843 V) and OER (Ei=10 = 1.504 V) in alkaline medium. Simultaneously, the assembled zinc-air batteries with open porous CoFe/SN C catalysts display high power density (169 mW cm-2) and outstanding stability (run stable for 5100 min). More importantly, density functional theory (DFT) calculation reveals that coupling of Fe-N4 and Co-N4 species can boost bifunctional catalytic activity originating from slightly weakened adsorption strength of ORR/OER intermediates on active sites.

Using first-principles calculations, we propose a novel metallic silicon hexaboride, Cmca-B6Si. This structure is dynamically and mechanically stable at ambient pressure. Furthermore, the formation energy of Cmca-B6Si is lower than those of synthesized Pnnm-SiB6 and SiB4, indicating that Cmca-B6Si is thermodynamically stable. The calculations of thermodynamic stability and structural inheritance indicate that Cmca-B6Si may be obtained by removing Li from the synthesized LiB6Si, that is, by imitating the preparation of Si24 and T-Graphene C4. The structure of Cmca-B6Si is a covalent three dimensional framework linked by B12 icosahedrons and Si atoms. The analysis of band structure and density of states reveals that Cmca-B6Si is metallic because of the partially occupied 2p and 3p electrons of B and Si atoms, respectively. The electron orbitals reveal that Cmca-B6Si has a novel two-dimensional metallicity. This study gives a fundamental investigation on the structural, phonon, and electronic properties of Cmca-B6Si.

Two multi-step (two-step and three-step) slow shot speeds were used in the vacuum die casting process of AZ91D magnesium alloy. The vacuum pressure variation in the die cavity before mold filling was monitored by using a pressure sensor. The microstructures of the produced castings were analyzed with optical microscope and image analysis software. The experimental results demonstrate that, the vacuum pressure in the die cavity at the beginning of mold filling is significantly reduced by using three-step slow shot speed, resulting in a low gas porosity level in the produced castings. At an appropriate multi-step slow shot speed, the dwell time of the liquid metal in the shot sleeve before mold filling can be reduced and the flow of the liquid metal in the shot sleeve at the later stage of the slow shot process can be restrained, which cause a low externally solidified crystal content in the produced castings.

The effects of vacuum assistance on the microstructure and mechanical properties of high-pressure die cast AZ91D alloy at different slow shot speeds were evaluated. Plate-shaped castings of AZ91D alloy were carried out on a TOYO BD–350V5 cold chamber die casting machine incorporated with a self-improved TOYO vacuum system. It was found that the vacuum pressure in the die cavity at the beginning of mold filling increases with the increase of slow shot speed, following a cubic polynomial curve, resulting in a decline in the porosity-reduction ability of vacuum assistance with the increase of slow shot speed. The externally solidified crystal (ESC) contents in conventional and vacuum die castings behave similar against the slow shot speed. The tensile properties of vacuum die castings were strongly influenced by the ESC content at relative low slow shot speeds. With the increase of slow shot speed, the influence of the gas porosity level in vacuum die castings would get prominent.

The HPLCâMS/MS method was developed to profile the dynamics of abscisic acid (ABA) and ABA-glucose ester (ABA-GE) after cloning glycosyltransferase enzyme family gene AtUGT71C5 into Arabidopsis thaliana. By constructing over-expression lines (OE) and down-expression lines (DN), we acquired mutant strains to analyze the function of AtUGT71C5. The multiple-reaction monitoring (MRM) was used for quantitative determination in negative mode. The transition was m/z 263.1â153.0 for ABA ([MâH]+), m/z 425.1â263.0 for ABA-GE ([MâH]+), and m/z 321.0â152.0 for chloramphenicol. The linear range was 0.8684â217.1Â ng/mL for ABA and 0.3920â196.0Â ng/mL for ABA-GE. The accuracy was 88.0â109.0% for ABA and 86.6â113.0% for ABA-GE; the inter-day and intra-day precisions were less than 5.4% for ABA and 8.9% for ABA-GE, respectively. This method is simple and sensitive enough for determination of ABA and ABA-GE in A. thaliana leaves. All the evidence confirmed the speculation that AtUGT71C5 can mediate abscisic acid homeostasis. Keywords: HPLCâMS/MS, ABA, ABA-GE, AtUGT71C5

A label-free electrochemical immunosensor using hollow structure nanomaterials based on its ordered porous structure and big surface area was designed. Au nanocage, with good conductivity, catalysis activity and biocompatibility, was prepared and immobilized on the graphene-midified surface of glassy carbon electrode (GCE) to adsorb antibody of microcystin(MC) directly. In the absence of MC, a high current response signal of electrochemical probe ([Fe(CN)6]3−/4− was obtained. When MCs bound specifically with its antibody immobilized on the sensor surface, the electron transfer resistance of the electrode increased, resulting in a decrease of the corresponding peak current of [Fe(CN)6]3−/4−. This change was in proportion to the concentration of MCs indirectly. The experiment conditions such as incubation time of antigen and concentration of antibody were optimized. The immunosensor showed a wide linear range of 0.05 μg L−1−1.0 mg L−1 and a detection limit of 0.017 μg L−1 to MC, with the advantages of good stability and simple production procedure. This sensor provided a new and simple means for the ultrasensitive determination of MCs in real water samples.

Using first-principles calculations, a novel B12-based ternary compound, NaB6Si structure is proposed in this work. This structure is confirmed to be dynamically, thermodynamically, and mechanically stable at ambient pressure. The formation energy of NaB6Si is lower than that of experimentally synthesized Na8B74.5Si17.5. The Vickers hardness is calculated to be 30.2 GPa, indicating NaB6Si is a promising hard material. The band structure and density of states reveal that NaB6Si is a wide band gap semiconductor with a band gap approximately 2.88 eV. This study provides a fundamental understanding of the structural, mechanical, and electronic properties in NaB6Si.

Based on the cellular automaton (CA) method, a numerical model was developed to simulate the dendritic growth of magnesium alloy with HCP crystal structure. The growth kinetics was calculated from the complete solution of the transport equations. By defining a special neighborhood configuration with the square CA cell, and using a set of capturing rules which were proposed by BELTRAN-SANCHEZ and STEFANESCU for the dendritic growth of cubic crystal metals during solidification, modeling of dendritic growth of magnesium alloy with different growth orientations was achieved. Simulation of equiaxed dendritic growth and columnar dendritic growth under directional solidification was carried out, and validation was performed by comparing the simulated results with the experimental results and those in the previously published works.

A near infrared universal quantitative analysis model was established to determinate the effective ingredient content in pesticide EC (hikernalisation) by the PLS (partial least squares) algorithm, the model predictive ability was evaluated by the external inspection method. The model was established among samples containing the same active ingredient from five different companies, and the model determination coefficient R 2 and RMSECV (root mean square error of cross validation) were 0.9997 and 0.0223, respectively, the relative error between predicted value and chemical value of the testing set samples was between −2.71% and 3.36%, which indicated that the method to determinate the effective ingredient content in pesticide EC by the established universal model can meet the need of pesticide market monitoring.