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Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is an attractive tool to analyze the bioactive small molecules but remains a great challenge owing to the serious background interference from conventional matrix with m/z 1000. Herein, we reported a dual-ion MALDI matrix of yolk-shell Ni/NiO nanoparticles anchored on nitrogen-doped graphene (Ni/NiO/N-Gr) to enhance MALDI performance. The Ni/NiO/N-Gr was synthesized via the pyrolysis and controllable oxidation strategy based on the nanoscale regulation of Kirkendall effect. The novel matrix showed the superior behavior for the analysis of various small molecular metabolites (amino acids, saccharides, spermidine, creatinine, hippuric acid, dopamine, and ascorbic acid) with high sensitivity, excellent salt tolerance, and favorable reproducibility in dual-ion modes compared to the traditional α-cyano-4-hydroxycinnamic acid (CHCA) and control substances (Ni/N-Gr and NiO/N-Gr). Meanwhile, we have realized accurate quantitation of blood glucose in mice with a linearity concentration range of 0.2-7.5 mM and qualitative detection of various endogenous small molecular metabolites in mice serum and urine samples. Especially, the Ni/NiO/N-Gr assisted LDI MS imaging (MSI) has exhibited the excellent spatial distribution of lipids in hippocampus region of mice brain. These results may provide an approach to explore the MALDI MS and MSI applications in clinical diagnosis.

Nowadays, more attention has been paid to nontoxic lead-free ferroelectric (FE) materials as the substitution of lead-based energy storage materials, due to the increasing environmental awareness. BaTiO3 (BT) has good comprehensive properties, however, its low breakdown electric field leads to the low energy storage density, which is the main challenge in BT-based ceramics. In this work, BT was modified by introducing the Bi(Ni2/3Ta1/3)O3 (BNT) component in order to reduce the field-induced strain and further enhance the breakdown strength. Effects of BNT component on the microstructures, relaxor characteristics, energy storage efficiency and field-induced strain were investigated systematically. The results indicate that the long-range ordered ferroelectric domains of BT ceramics are destroyed by the incorporation of the BNT component, resulting in the distortion of the polar regions. As a result, the BT-BNT ceramics possess slim P-E hysteresis and extremely low remnant polarization, owing to the phase transition from the normal ferroelectrics to relaxor ferroelectrics. The reduced strain promotes to the increase of the breakdown field strength. Ultimately, the energy storage efficiency of BT-BNT ceramics can reach 87.15%, revealing a promising application in energy storage device.

As a novel processing technology, plasma spray-physical vapor deposition (PS-PVD) enables coatings to be deposited mainly from vapor phase. To explore the potential advantages of such a plasma spray-based processes, the deposition mechanisms and their dependency on process conditions should be better investigated. In this work, yttria partially stabilized zirconia thermal barrier coatings with quasi-columnar structure were fabricated by PS-PVD. The morphologies of the coatings for each set of deposition durations (from 30 ms to 100 s) and spray distances range from 800 to 1000 mm were studied. Besides, a design-of-experiment was used to investigate the non-line-of-sight capability of PS-PVD coatings, which were deposited on flat superalloy substrates that mounted on a static cylindrical graphite holder approximately 40 mm in diameter at various deposition angle (from 0° to 270°). Moreover, the residual stresses in the topcoat and thermally grown oxide scale were measured non-destructively using Raman spectroscopy and photoluminescence piezospectroscopy, respectively. The stage growth process of PS-PVD coatings was obtained by electron backscattered diffraction characterization of the crystal orientations and distributions of crystal size. The various microstructures of the coatings help to improve the understanding of the deposition mechanisms of PS-PVD coatings.

It was published that zirconate coatings containing Gd/Yb and yttria-stabilized zirconia (YSZ) coatings with high Y content had good calcium-magnesium-aluminum-silicate (CMAS) corrosion resistance. However, there are few reports on CMAS resistance of zirconia-based thermal barrier coatings (TBCs) doped with Y, Gd and Yb. This article intends to explore the role of Y, Gd and Yb in resisting CMAS corrosion of zirconia-based TBCs. The purpose is to optimize the rare earth modification of zirconia-based TBCs. 8YSZ and ZrO2-9.5Y2O3-5.6Yb2O3-5.2Gd2O3 free-standing TBCs were produced by air plasma spraying (APS) with commercial powders. The CMAS corrosion behavior and failure mechanism of these coatings were studied by heat treatment at 1350 °C. The microstructure and composition were characterized. The results showed the CMAS deposited on the surface of 8YSZ/YSZ-Yb-Gd coatings gradually penetrated into coatings. ZrSiO4 and m-ZrO2 were observed in the shallow layer of coatings. The diffusion rate of Y3+ in coatings into CMAS was greater than that of Gd3+ and Yb3+. Compared with YSZ coatings, CMAS penetrated deeper in YSZ-Yb-Gd coatings after the same corrosion time. The spallation of YSZ-Yb-Gd coatings occurred earlier than 8YSZ. In general, adding a small amount of Yb and Gd did not improve the CMAS resistance of YSZ TBCs.

DNA double strand break (DSB) is a kind of highly toxic damage, causing genomic instability, chromatin aberration and cancer. A number of conserved DSB damage repair pathways have been found in eukaryotes, most notably classical non-homologous end joining (cNHEJ) and homologous recombination (HR). These two repair pathways resolve most DSBs in cells. For different types of DSBs, cells could wittily choose the optimal approach with the lowest risk for genomic instability. Relying on the developing cell imaging techniques and molecular biological methods, sophisticated mechanism of DSB repair pathway choice has been revealed. The regulation mechanism of pathway choice is complex and precise. In this review, the effect factors such as the structures of the broken terminals, the degree of DNA end resection, cell cycle, chromatin environment, histone modification and RNA metabolism on the DSB repair pathway choice are discussed, showing the diversity and flexibility of DSB repair pathway choice.

Three different kinds of thermal barrier coatings (TBCs) — 8YSZ, 38YSZ and a dual-layered (DL) TBCs with pure Y2O3 on the top of 8YSZ were produced on nickel-based superalloy substrate by air plasma spraying (APS). The Calcium–Magnesium–Aluminum-Silicate (CMAS) corrosion resistance of these three kinds of coatings were researched via burner rig test at 1350 °C for different durations. The microstructures and phase compositions of the coatings were characterized by SEM, EDS and XRD. With the increase of Y content, TBCs exhibit better performance against CMAS corrosion. The corrosion resistance against CMAS of different TBCs in descending was 8YSZ + Y2O3, 38YSZ and 8YSZ, respectively. YSZ diffused from TBCs into the CMAS, and formed Y-lean ZrO2 in TBCs because of the higher diffusion rate and solubility of Y3+ in CMAS than Zr4+. At the same time, 38YSZ/8YSZ + Y2O3 reacts with CAMS to form Ca4Y6(SiO4)6O/Y4·67(SiO4)3O with dense structure, which can prevent further infiltration of CMAS. The failure of 8YSZ coatings occurred at the interface between the ceramic coating and the thermally grown oxide scale (TGO)/bond coating. During the burner rig test, the Y2O3 layer of the DL TBCs peeled off progressively and the 8YSZ layer exposed gradually. DL coatings keep roughly intact and did not meet the failure criteria after 3 h test. 38YSZ coating was partially ablated, the overall thickness of the coating is thinned simultaneously after 2 h. Therefore, 8YSZ + Y2O3 dual-layered coating is expected to be a CMAS corrosion-resistant TBC with practical properties.

Ca2SiO4 coatings with and without metallic bonding layer (NiCr) have been prepared by atmospheric plasma spraying. Microstructure and corrosion behavior of the coatings with various exposure periods in simulated seawater were investigated by means of scanning electron microscopy, energy dispersive spectrometry, potentiodynamic polarization and electrochemical impedance spectroscopy. The results revealed that the after immersion, a layer of urchin-like aragonite (CaCO3) was formed on the surface and a dense silica-rich layer was found between CaCO3 and Ca2SiO4 layer. Besides, self-sealing behavior was observed in the Ca2SiO4 layers. Compared with the immersed coatings, as-sprayed coatings exhibited the highest corrosion current densities, the lowest polarization resistance and charge transfer resistance. The presence of the metallic bonding layer slightly decreased the corrosion resistance of Ca2SiO4 coatings. The plasma-sprayed Ca2SiO4 coatings have a potential use in marine corrosive environments.

Chromosome translocation is a major cause of the onset and progression of diverse types of cancers. However, the mechanisms underlying this process remain poorly understood. Here, we identified a non-homologous end-joining protein, IFFO1, which structurally forms a heterotetramer with XRCC4. IFFO1 is recruited to the sites of DNA damage by XRCC4 and promotes the repair of DNA double-strand breaks in a parallel pathway with XLF. Interestingly, IFFO1 interacts with lamin A/C, forming an interior nucleoskeleton. Inactivating IFFO1 or its interaction with XRCC4 or lamin A/C leads to increases in both the mobility of broken ends and the frequency of chromosome translocation. Importantly, the destruction of this nucleoskeleton accounts for the elevated frequency of chromosome translocation in many types of cancer cells. Our results reveal that the lamin A/C-IFFO1-constituted nucleoskeleton prevents chromosome translocation by immobilizing broken DNA ends during tumorigenesis.

using the synthesized nickel particle/graphene (Ni/Gr) composite as a new matrix and adsorbent, a matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) platform was constructed for the efficient analysis of various drugs, amino acids and other small biological molecules. Compared with the traditional matrix of 2, 5-dihydroxyphenyl acid (DHB) and a series of comparison materials (Gr, Ni-1/gr and Ni-5/gr), Ni-2/gr as MALDI matrix has the advantages of low background noise, high ionic strength, high signal-to-noise ratio and wide linear range (0.01 ~ 50 μmol/L, 0.2 ~ 50 μmol/l and 0.05 ~ 60 μmol/l) when analyzing the molecules of resveratrol, 6-gingerol and rutin in the positive ion mode. The detection limits (LODs) of resveratrol, 6-gingerol and rutin were respectively 0.0038, 0.09 and 0.02 μmol/L. Ni-2/gr complex has the characteristics of high specific surface area, rich mesoporous structure, a large number of sp2 structures, strong UV absorption and high saturation magnetization value (MS). It can be used as an adsorbent to magnetically enrich phenylalanine, tryptophan and tyrosine, and can also be used to magnetically enrich low concentration tryptophan in mouse serum samples.

Through the overall situation of athletes’ competition pressure, the pressure level of participating athletes can be understood and revealed. Analyzing the sources of stress and influencing factors of athletes can find measures to relieve and reduce stress and provide theoretical reference for the regulation of athletes’ competition pressure. Based on genetic algorithm and neural network theory, this paper proposes a method of tracing the sports competition pressure based on genetic algorithm backpropagation (BP) neural network to solve the problem that traditional neural network learning algorithm is slow and easy to fall into local minimum. There is no significant difference between male and female athletes in the level of competition pressure. Athletes have the same training methods and the same goals, and the competition pressure tends to be the same, with no obvious difference; athletes with different educational backgrounds have no significant differences in training, academics, sports injuries, interpersonal relationships, social expectations, and evaluations. Due to the particularity of the stage, the competition pressure of fourth-year undergraduate and third-year masters is significantly higher than that of other grades. The number of athletes participating in college table tennis tournaments has very significant differences in competition dimensions. There is significant difference in training and self-expectation dimension difference. The competition pressure of athletes who participated in the college table tennis championship for the first time was significantly higher than that of athletes who participated repeatedly. There were significant differences between athletes before and after adapting to the venue. Before adapting to the venue, the competition pressure of athletes is generally greater. After adapting to the venue, the competition pressure of athletes has been relieved.

Segmentation-crack structured yttria-stabilized zirconia (YSZ) thermal barrier coatings (TBCs) were deposited by atmospheric plasma spraying (APS) using a Triplex Pro&trade, 200 gun. In this work, free-standing coating specimens (~700 &mu, m) were isothermally heat-treated in air from 1200 to 1600 &deg, C for 24 h and at 1550 &deg, C for 20 to 100 h, respectively. The thermal aging behaviors such as microstructures, phase compositions, grain growth and mechanical properties were characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and a Vickers hardness test. The results indicated that the as-sprayed coatings mainly consisted of metastable tetragonal (t&prime, YSZ) phase, but the t&prime, YSZ gradually partitioned into equilibrium tetragonal (t-YSZ) and cubic (c-YSZ) phases due to yttrium diffusion during thermal exposure, and with an improvement in temperature, the c-YSZ may retain or transform into another yttrium-rich tetragonal (t&Prime, YSZ) phase. The transformation of t-YSZ to monoclinic phase (m-YSZ) has occurred after 1550 &deg, C/40 h heat treatment, and the content of the m-YSZ phase increased with the prolongation of the thermal exposure time. The variations of Vickers hardness have a correlation with pores healing and grain growth, which might be attributed to the coating sintering and m-YSZ phase formation. Furthermore, the growth pattern of the grains was investigated in detail. In service, cracks and pores proceeded along the grain boundaries, especially surrounding the small grains. It is conducive to the engineering application of TBCs fabricated with the Triplex Pro&trade, 200 gun.

In Earth's high-latitude ionosphere, the poleward motion of east–west elongated auroral arcs has been attributed to standing hydromagnetic waves, especially when the auroral arcs appear quasi-periodically with a recurrence time of a few minutes. The validation of this scenario requires spacecraft observations of ultra-low-frequency hydromagnetic waves in the magnetosphere and simultaneous observations of poleward-moving auroral arcs near the spacecraft footprints. Here we present the first observational evidence from the multi-spacecraft THEMIS (Time History of Events and Macroscale Interactions during Substorms) mission and the conjugated all-sky imager to support the scenario that standing hydromagnetic waves can generate the quasi-periodic appearance of poleward-moving auroral arcs. In this specific event, the observed waves were toroidal branches of the standing hydromagnetic waves, which were excited by a pulse in the solar wind dynamic pressure. Multi-spacecraft measurements from THEMIS also suggest higher wave frequencies at lower L shells (consistent with the distribution of magnetic field line eigenfrequencies), which indicates that the phase difference across latitudes would increase with time. As time proceeds, the enlarged phase difference corresponds to a lower propagation speed of the auroral arcs, which agrees very well with the ground-based optical data.

It is still a challenge to improve ionization efficiency of saccharides in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Herein, the highly curved onion-like carbon nanoparticles (OCS) were synthesized from the low-price candle raw via a facile strategy. The unique nanostructure of OCS showed large surface area with plentiful mesoporous architecture, highly curved sp

Plasma spray-physical vapor deposition (PS-PVD) is an advanced technique to fabricate quasi-columnar structured thermal barrier coatings (TBCs) with excellent thermal cyclic lifetime. In this study, PS-PVD TBCs were investigated via burner rig test. The residual stresses in both of the topcoat layer and the thermally grown oxide (TGO) scale were measured non-destructively using Raman spectroscopy and Cr3+ photoluminescence piezo-spectroscopy, respectively. Evolution of the microstructures and distribution of residual stresses in such kind structured TBCs before and after thermal cycling test were investigated. The accumulated tensile stress in the as-sprayed ceramic topcoat changed to compressive state after 100 cycles and then gradually increased. In addition, the mapping compressive stresses in the TGO measured through the ceramic topcoat surface decreased rapidly and then essentially maintained at a relatively stable state with further testing. Moreover, the pre-heating of the bondcoat could significantly affect the stress distribution in the TGO, in contrast, no obviously influence on the stresses in the YSZ topcoat.

Columnar-structure is favourable to the durability of thermal barrier coatings (TBCs), and the efficacy of TBCs increases with the thickness of the TBCs. In this study, thick columnar YSZ coatings (∼1.5 mm) were deposited by multiple PS-PVD processes. The phase compositions, microstructures and mechanical properties were examined with various techniques including X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and nanoindentation. Results show that there are only tetragonal phase on the top surface while both monoclinic and tetragonal zirconia are present on the bottom surface. The first layer of the coatings is composed of randomly oriented grains. Immediately after the quasi-equiaxed zone, columns start to grow. The top coatings exhibit looser microstructure compared with the middle and bottom regions, and thus have lower values of hardness and Young’s modulus.

Advanced thick thermal barrier coatings (TTBCs) have attracted extensive attentions due to the embedded segmentation-crack structure and excellent thermal insulation performance. The thermal shock life and failure behaviors of advanced TTBCs still remain a challenge. The objective of this work is to well understand the effect of microstructure on the coating cracking behavior in atmospheric plasma sprayed TTBCs system, in which the extended Raman spectroscopy (RS) techniques are used to obtain an in-depth understanding on how the oxidation affects the stress distribution in coatings and in turn, the causes of the observed cracking. Results show that the TTBCs deposited by the highly purified feedstock exhibit excellent thermal shock life at 1100 ℃ due to the well-proportioned and compact structure and built-in vertical cracks. After thermal shock test, the broken regions usually occur at the horizontal cracks and vertical cracks area within top-coat, and top-coat/bondcoat interface, which may suggest that each structural mutation parts are prone to causing the TTBCs instabilities. Cracks are propagated and extended under thermal tensile stress. The coating failure is most possibly dominated by the accumulated residual stress generated due to thermal expansion mismatch between the substrate and top-coat. In addition, the good thermal shock resistance have a close relationship with the newly formed vertical cracks at the bottom of ceramic coating near the top-coat/bondcoat interface.

In recent years, numerous techniques have been developed to mimic nacre-like hierarchical architectures in order to improve the damage tolerance of materials. We present herein a simple strategy to fabricate such a hierarchical architectured Al2O3–Y2O3 composite coating via atmospheric plasma spraying. The evolution of the phase and microstructure of the Al2O3–Y2O3 composite coating were characterized under conditions of high-temperature exposure in air at 800-1350 °C. The hardness and porosity of several typical coatings were determined. In situ formation of dense hierarchical architectured Al2O3–YAG composite coating with improved hardness was achieved after heat treatment at 1350 °C. Compared with Al2O3 coating, elevated toughness was found for the hierarchical architectured Al2O3–YAG composite coating, which can be ascribed to the distribution of YAG phase that contributed to crack termination and deflection, and microbridging. After thermal aging treatment at 1350 °C, the hierarchical architectured Al2O3–YAG composite coating was quite stable after 100 h of thermal exposure. Furthermore, the Al2O3–Y2O3 composite coating exhibited superior sintering resistance compared with the Al2O3 coating.

The microstructure and wear resistant performance of plasma-sprayed Al2O3–Y3Al5O12 (YAG) coating were investigated. As-sprayed Al2O3–YAG coating was chiefly composed of amorphous phase, which may reveal superplastic feature in supercooled liquid region (from 503.0 °C to 906.5 °C). The as-sprayed Al2O3–YAG coating exhibits fine plasticity and toughness under the following conditions: a load of 2000 N, a rotational speed of 500 rpm and worn surface temperature above 500 °C, which significantly contributes to relieve accumulated coating stress and maintain the coating integrity. Therefore, plasma-sprayed Al2O3–YAG coating possesses excellent wear resistance under severe conditions.

In the current work, by means of suspension plasma spraying (SPS), yttria stabilized zirconia splats and coatings were deposited onto mirror-polished and rough substrates, respectively. The splats were characterized by scanning and transmission electron microscopes (TEM). The influence of substrate temperature on splat morphology was analyzed via comparing the splats deposited onto substrates held at different temperatures, namely room temperature (RT), 300 °C, 500 °C, 700 °C and 900 °C. As the substrates were heated from RT to 300 °C, the feature of splats changed rapidly. However, when the substrate temperature further increased, the variation of morphology was found less conspicuous. Integrated splats were peeled off from the substrate using a “plating and etching” approach for TEM examination. The observation on morphological and crystallographic features of splats revealed that the cooling rate during impacting and spreading of SPS splats was lower than that of splats deposited by conventional atmospheric plasma spraying. Based on the characteristics of splats, a modified mechanism consisting changing of droplets trajectory and shadowing effect was proposed to explain the formation of the microstructure of as-sprayed SPS coating. In addition, the coatings were also examined by X-ray diffraction and nano-indenter to determine the phase composition and microhardness, respectively.

In the current study, alumina and alumina-yttria composite coatings were prepared on stainless steel substrates via atmospheric plasma spraying. Their dry sliding wear performances against graphite under severe conditions were evaluated by using a ring-on-disk tribometer. The results showed that the addition of yttria has successfully decreased the friction coefficients of the alumina coatings. Further, the temperatures in the friction process rose sharply in the initial wear stage and then reached the state of thermal equilibrium. The temperatures of alumina-yttria coatings at thermal equilibrium stages were lower than those of alumina coatings, which may be due to their lower friction combined with the slightly higher thermal conductivity. High friction interface temperatures were considered to greatly aggravate the thermal stress, thereby intensifying the cracking of alumina coatings. Additionally, the addition of yttria improved the toughness of composite coatings and the related crack propagation resistance.

Background Myocardial ischemia (MI) could cause many complications, such as arrhythmia, ischemic cardiomyopathy, which could lead to angina and myocardial infarction. The clinical efficacy of dezocine, morphine and nalbuphine are becoming dominated in China market. This aim of this study was to investigate the effects of dezocine, morphine and nalbuphine on electrical pain threshold, temperature pain threshold and cardiac function in rats with MI. Methods A rat model of MI was established by ligating the coronary artery. Rats in the model group were injected with dezocine, morphine, nalbuphine and 0.9% normal saline. The effects of the three analgesics on MI rats were evaluated by comparing the electrical pain threshold, temperature pain threshold, and cardiac function index. Results The electrocardiogram revealed that the model of MI was successful. The results of the electrical pain threshold and temperature pain threshold tests revealed that nalbuphine was the most sensitive after medication, followed by dezocine, and the sensitivity of morphine was the lowest. These three drugs reached its peak at two hours after administration. The analgesic effect of dezocine on electrical stimulation was the best, while nalbuphine had the best effect on temperature. The efficacy of dezocine decreased with time, while morphine basically failed at four hours after administration. The peak time of these three kinds of analgesics was selected to detect the cardiac function index in each group. Morphine had the least influence on the cardiac function index of rats, followed by nalbuphine and dezocine. Conclusions These results show that the analgesic effect of nalbuphine had the earliest and best effect with the longest duration on temperature, and had less influence and higher safety in the cardiac function test of MI rats. Hence, nalbuphine is a relatively good analgesic for MI patients. The present study provides a database for the selection of analgesics in patients with MI.

The plasma spray&ndash, physical vapor deposition (PS&ndash, PVD) process has received considerable attention due to its non-line of sight deposition ability, high deposition rates, and cost efficiency. Compared with electron beam&ndash, physical vapor deposition (EB&ndash, PVD), PS&ndash, PVD can also prepare thermal barrier coatings (TBCs) with columnar microstructures. In this paper, yttria-stabilized zirconia (YSZ) coatings were fabricated by PS&ndash, PVD. Results showed that the as-deposited coating presented a typical columnar structure and was mainly composed of metastable tetragonal (t&prime, ZrO2) phase. With thermal exposure, the initial t&prime, phase of YSZ evolved gradually into monoclinic (m-ZrO2) phase. Significant increase in hardness (H) and the Young&rsquo, s modulus (E) of the coating was attributed to the sintering effect of the coating during the thermal exposure, dependent on exposure temperature and time. However, the values of H and E decreased in the coatings thermally treated at 1300&ndash, 1500 &deg, C for 24 h, which is mainly affected by the formation of m-ZrO2 phase.

In this study, dicalcium silicate (Ca2SiO4) coatings were deposited on stainless steel substrates by atmospheric plasma spraying. Salt spray and immersion tests were carried out to evaluate corrosion performance and XRD, SEM, and EDS were used to analyze phase composition and microstructure. During corrosion testing, calcium carbonate crystals appeared on coating surfaces and the pores were filled with hydration products, producing denser coatings. Potentiodynamic polarization curves and electrochemical impedance spectroscopy plots indicated that the corrosion resistance of the coatings increased after immersion in saltwater and artificial seawater, and in the latter case, a silica-rich layer was observed between the coating and the calcium carbonate crystals.

It is of significance to analyze various small molecules with high efficiency using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). In this work, we synthesized N and B dual-doped 3D carbon (N, B-C) nanofiber as a promising MALDI matrix through a facile impregnation and thermal pyrolysis process. Compared to the control C nanofiber, the N and B codoping could enhance surface area, functional groups, defective and active sites, which was conducive to adsorb the laser and enrich the desorption/ionization of analytes. For the first time, the N, B-C nanofiber was utilized as a novel matrix for MALDI-TOF MS analysis of various small molecules both in the positive-ion and negative-ion modes. This matrix showed high signal to noise (S/N) ratio, excellent salt-tolerance, and homogeneous ion distribution for the analysis of amino acids, saccharides, polymers and surfactant, which was obviously superior to the traditional α-cyano-4-hydroxycinnamic acid (CHCA) and the control C nanofiber matrix. Noticeably, the wide linear ranges (0.05–5 mM) of glucose was achieved by MALDI-TOF MS with N, B-C nanofiber matrix. Meanwhile, the MALDI-TOF MS imaging could observe the change of different content glucose based on the ion peak of [M + Na]+. Furthermore, N, B-C nanofiber-assisted LDI-TOF MS has also been applied to identify and analyze the saccharides in the natural honey.

Plasma spray-physical vapor deposition (PS-PVD) is a novel technique which can offer new opportunities to obtain advanced microstructures. In this study, dense yttria-stabilized zirconia (YSZ) coatings were deposited using PS-PVD with proper parameters. The dependencies of the microstructure of the as-sprayed coatings on axial spray distance and radial position were discussed. Four typical coatings were selected for the current work. The corresponding microstructures, phase compositions and mechanical properties were studied in detail. These as-sprayed coatings had dense lamellar or lamellar/columnar hybrid microstructures, the lowest porosity was 0.44%. Both monoclinic and tetragonal zirconia were detected in the as-sprayed coatings. The distribution of yttrium was not homogeneous, especially in the coatings deposited at shorter spray distance. Furthermore, oxygen got lost partly during the spraying process with decreasing spray distance. The hardness ( H ) and Young's modulus ( E ) of the coatings changed simultaneously with the different microstructures. The maximum values of H and E were 16.6±0.6 and 234.3±10.1 GPa respectively, which were found in the densest coatings. The dense PS-PVD ceramic coatings might be applicable in anti-corrosion fields (such as alkali corrosion, marine corrosion and hot corrosion).

In the present study, Al 2 O 3 and Al 2 O 3 –Y 2 O 3 composite coatings were deposited by atmospheric plasma spraying. The microstructure, hardness, thermal conductivity and dry sliding wear behavior of the coatings were examined. The results showed that the mass ratio of α-Al 2 O 3 /γ–Al 2 O 3 in as-sprayed Al 2 O 3 coating was 0.08. However, the corresponding value in Al 2 O 3 –Y 2 O 3 composite coating was 0.53. This exhibits salient influence on the stabilization of α-Al 2 O 3 . The addition of Y 2 O 3 was beneficial to improve the thermal conductivity of the composite coating. In addition, Al 2 O 3 –Y 2 O 3 composite coating/graphite pairs possess more stable friction coefficients, which may be related to the formation of more effective and stable graphite transferred film on the surface of the coating subjected to abrasion. Further, the wear resistance of Al 2 O 3 –Y 2 O 3 composite coatings was superior to that of Al 2 O 3 coatings.

Two kinds of segmentation-crack structured YSZ thick thermal barrier coatings (TTBCs) were deposited by suspension plasma spraying (SPS) and atmospheric plasma spraying (APS) with nano-based suspension and agglomerated particles, respectively. The phase composition, microstructure evolution and failure behavior of both TBCs before and after thermal shock tests were systematically investigated. Microstructure of the APS coating exhibits typical segmentation-crack structure in the through-thickness direction, similar with the SPS coating. The densities of segmentation-crack in APS and SPS coatings were about 3 cracks mm −1 and 4 cracks mm −1 , respectively. The microstructure observation also showed that the columnar and equiaxed grains existed in the SPS coating. As for the thermal shock test, the spallation life of the APS TTBCs was 146 cycles, close to that of the SPS TTBCs (166 cycles). Failure of the APS coating is due to the spallation of fringe segments and splats.

The paper studies the neural mechanism of advanced volleyball players' decision-making behavior based on sports situations. In this study, the author adopts behavioral test and to try to systematically explore the sports situation-based neural mechanism and its plasticity. The study finds that the volleyball decision-making test system can test players' decision-making behavior at different sports levels with a high validity. There is a significant difference in the decision-making behavior of players at different sports levels, and high level athletes achieve high accuracy rate and possess quick reaction. The brain gray matter volume near lateral occipital lobe responsible for visual information process in the right cerebral hemisphere and the thickness of the cerebral cortex of the high-level volleyball players and those of the ordinary are significantly different.

Highly dispersed silicon carbide powders were prepared by a solvothermal-assisted sol–gel process with tetraethyl orthosilicate and phenolic resin as starting materials and carbothermal reduction reactions at a relatively low temperature (1400–1600 °C). Investigated by X-ray diffraction, transmission electron microscopy, scanning electron microscope and the nitrogen adsorption–desorption isotherm measurements, the obtained SiC powders had an average crystallite size of 200 nm and high specific surfaces areas of 149 m2/g. Besides, mechanism for preparation of highly dispersed SiC powders was proposed.

53BP1 with its downstream proteins, RIF1, PTIP and REV7, antagonizes BRCA1-dependent homologous recombination (HR) and promotes non-homologous end joining (NHEJ) in an unclear manner. Here we show that REV7 forms a complex with two proteins, FAM35A and C20ORF196. We demonstrate that FAM35A preferentially binds single-strand DNA (ssDNA) in vitro, and is recruited to DSBs as a complex with C20ORF196 and REV7 downstream of RIF1 in vivo. Epistasis analysis shows that both proteins act in the same pathway as RIF1 in NHEJ. The defects in HR pathway to repair DSBs and the reduction in resection of broken DNA ends in BRCA1-mutant cells can be largely suppressed by inactivating FAM35A or C20ORF196, indicating that FAM35A and C20ORF196 prevent end resection in these cells. Together, our data identified a REV7–FAM35A–C20ORF196 complex that binds and protects broken DNA ends to promote the NHEJ pathway for DSB repair.

In this study, Ca2SiO4 coating was sprayed on stainless steel substrate and the corrosion resistance of the as-sprayed coating was studied in salt water. At the same time, Al2O3 coatings were produced by air-plasma-sprayed technology as comparison. Immersion test was carried out to evaluate the protection performance of coatings. Potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) plots were also analyzed. The results indicated that Ca2SiO4 coatings showed a better protection performance than Al2O3 coatings. During the immersion, various calcium carbonate crystals appeared on the surface of Ca2SiO4 coatings. Ca(OH)2 was released from Ca2SiO4 coatings into NaCl aqueous solution, increasing the alkalinity, which is in favor of the formation of passivation film, and thus improves the corrosion resistance. Ca2SiO4 coatings became denser after immersion due to the fact that the pores and micro cracks were filled with hydration products i.e., hydrated calcium silicate (C–S–H) gel. On the contrary, the microstructure of Al2O3 coatings became loose and obvious rusty spots were observed on the surface after the immersion test.

In this paper, Al 2 O 3 –Cr 2 O 3 composite coating was fabricated by plasma spraying. It has better mechanical performances than Al 2 O 3 coating. Erosion–wear resistance of the coatings was evaluated by a new type of solid particle impact test (slurry jet). Slurry was mixed with compressed air in the nozzle and eventually injected on coating surface at high velocity. Injected slurry on coating surface resulted in a wear progression (wear rate) proportionately to the erosion strength of the coating material. Al 2 O 3 –Cr 2 O 3 composite coating possesses better erosion–wear resistance than pure Al 2 O 3 coating.

In this work, yttria-stabilized zirconia splats deposited onto different bond coatings were characterized. The influence of both substrate topography and temperature on splat morphologies was investigated. The substrate surface was described using a method characterized by multi-level roughness. On non-heated substrate, the peak-valley structure in scale of micrometer contributed to the formation of crater-like holes on splats. The amount of such holes was reduced with the increase of substrate temperature. It was also observed that on micro-smooth surface, island-like fragments in the center of splat would warp and their edges could be detached from the underlying substrate, especially when the substrate was heated. The obtained results reveal that the influence of substrate pre-heating on the splat formation is realized via thinning the air film near substrate surface.

In the present study, Cr2O3–Al2O3 composite coatings were fabricated by atmospheric plasma spraying (APS) technique. Aluminum phosphate with small fraction of Al2O3 nanoparticles was applied as high-temperature sealant to enhance the anti-corrosion performance of the coatings. The inorganic sealant significantly reduced the open pore of the as-sprayed coatings and showed low shrinkage after heat treatment (600 °C, 30 min). Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and salt spray tests were used to assess anti-corrosive characteristics of the coatings. The sealants resulted in an augment of corrosion resistance properties of the coatings both before and after heat treatment, indicating effective sealing and good high temperature applicability. The sealed Cr2O3–Al2O3 composite coatings have a potential use in severe corrosion condition.