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Additional file 1: Table S1. The shRNA sequences of HIGD2A and the primer sequences used in real-time PCR analysis. Figure S1. Diagnostic and prognostic value of HIGD2A expression and its correlation with clinical features. A Representative immunohistochemistry images of HIGD2A expression in normal liver tissues and liver cancer tissues from the HPA. B The protein level of HIGD2A in normal hepatocyte L02 cell line and different liver cancer cell lines. C–F HIGD2A expression in different status of T stage (C), pathologic stage (D), vascular invasion (E) and OS event (F). G–J Kaplan–Meier plots of OS for HIGD2A expression levels in subgroups including T stage: T1 (G), N stage: N0 (H), M stage: M0 (I) and pathologic stage: stage I (J). K Nomogram for OS prediction, with T stage, N stage, M stage, histologic grade and expression of HIGD2A applied as parameters. L Calibration curves of the nomogram for 1-, 3-, 5-year survival prediction. *P < 0.05, **P < 0.01. Figure S2. Knockdown of HIGD2A impedes MHCC97H cells proliferation and migration. A Western blot assay for total HIGD2A protein expression in HIGD2A-knockdown MHCC97H cells. B Left, colony formation of MHCC97H cells transfected shCtrl or shHIGD2A.1. Right, quantification of colony formation based on three independent assays. C The proliferation ability of MHCC97H cells infected with shCtrl lentivirus or shHIGD2A.1 lentivirus was measured by CCK8 assay at the indicated time points. D, E Flow cytometry analysis of Annexin V/7-AAD double stained HepG2, Huh7 and MHCC97H cells transfected shCtrl or shHIGD2A.1. Representative flow cytometric plot (D) and the proportion of apoptosis cells (E). F Annexin V/7-AAD apoptosis assay of L02 cells after HIGD2A gene silencing. Left, representative flow cytometric plot. Right, the proportion of apoptosis cells. G Left, cell migration ability of MHCC97H cells transfected shCtrl or shHIGD2A.1 was analyzed by Transwell assay. Right, quantitative data of migrated cells. Results shown are mean ± SEM. an unpaired t-test was used. *P < 0.05, **P < 0.01, ***P < 0.001, ns, not significant. Scale bar, 100 µm. Figure S3. HIGD2A knockdown inhibited the proliferation and migration of HCC cells in vitro. A, B Colony formation experiments for the effect of HIGD2A knockdown with shRNA on the proliferation of HepG2 and Huh7 cells. C, D The effect of HIGD2A knockdown on the growth of HepG2 and Huh7 cells was detected by CCK8 assays. E The effect of HIGD2A knockdown on cell apoptosis was detected by western blot. F, G Transwell chamber was used to evaluated the effect of HIGD2A knockdown on the migration of HepG2 and Huh7 cells. Results shown are mean ± SEM. an unpaired t-test was used. *P < 0.05, **P < 0.01 and ***P < 0.001. Scale bar, 100 µm. Figure S4. Depletion of HIGD2A induces mitochondrial stress in MHCC97H. A, B Intercellular ATP level in MHCC97H (A) and L02 (B) cells transfected with shCtrl or shHIGD2A.1. C Immunofluorescent (IF) images showing mitochondria morphology in MHCC97H transfected with shCtrl or shHIGD2A.1. Left, representative IF images (magenta, MitoTracker; yellow, DAPI) and 3D mitochondria reconstruction of shCtrl- and shHIGD2A-infected MHCC97H cell. Scale bar, 5 μm; Sphericity heat map, 0.326–0.915. Right, sphericity analysis of 3D reconstructed mitochondria (results are presented as mean ± SD). D Left, oxygen consumption rate (OCR) in MHCC97H transfected with shCtrl or shHIGD2A.1 was measured by seahorse analyzer. Right, basal respiration rate and maximal respiration capacity are shown. E Comparison of Basal Respiration among L02 and HCC cells. Results shown are mean ± SEM. A Mann–Whitney test was used. *P < 0.05, **P < 0.01 and ***P < 0.001; ns, not significant.

The effect of SrAl2O4, FeAl2O4, and FeO derived from the solid-state reaction between Fe, Al, and SrSO4 during the hot pressing sintering process on the tribological properties of Fe-Al-SrSO4 (FA-S...

Hypothesis Flexible and wearable hydrogel strain sensors have attracted significant attention for human activity monitoring and electronic skins. However, it remains a great challenge to develop an integrated hydrogel strain sensor showing intrinsic adhesive performances, tunable mechanical and high strain-sensitive properties. Marine mussels show a superior capacity to adhere to various substrates (including organic and inorganic), while polycaprolactone (PCL) can be easily modified into crosslinkers with different degrees of functionality (bi-, tri-, and quadri-functional groups) to control the crosslinking density. Therefore, the developed mussel-inspired 3,4-dihydroxyphenyl- l -alanine acrylamide–polycaprolactone ( l -DMA–PCL) hydrogels could address these issues and serve as the potential wearable strain sensors for biomaterials and healthcare monitoring. Experiments l -DMA monomers were successfully crosslinked by functionalized PCL (bi-, tri-, and quadri-functional) using UV light (wavelength ~ 365 nm) to prepare the l -DMA–PCL hydrogel. Adhesive behaviors, tunable mechanical properties and strain sensing performances of the l -DMA–PCL hydrogels were systematically studied. Findings The l -DMA–PCL hydrogel exhibited reversible adhesion to various material substrates (including steel, aluminum, ceramics, poly(ethylene terephthalate) (PET), wood, rubber, even for polypropylene (PP) and polytetrafluoroethylene (PTFE)) as well as skin. Moreover, the mechanical properties (stress: 50.2–72.4 KPa, strain: 700–1140%, Young’s modulus: 8.6–14.8 KPa, and toughness: 16.4–53.6 KJ/m3) of the hydrogels could be readily tuned by the modulation of functionality degree (bi-, tri-, and quadri-functional) of PCL. Intriguingly, the hydrogel-based wearable strain sensor showing high conductivity (0.0550 S/cm) and sensitive responses to both large (e.g., joint bending) and subtle human motions (e.g., frowning and speaking). Based on these achievements, this work provides new insights into the development of hydrogel with adhesiveness, controllable mechanical performance and high strain sensitivity as a flexible and wearable hydrogel strain sensors.

The effect of the interaction between SrO and SrAl4O7 with monoclinic and/or orthorhombic structures on the tribological performance of NiCr-Al2O3 composites was evaluated over a wide temperature range. The results indicated that the formation of SrO and SrAl4O7 with monoclinic and/or orthorhombic structures was effective in improving the friction and wear properties of the sintered composites at elevated temperatures. At 400 °C, the monoclinic-SrAl4O7, SrO and oxides (NiCr2O4, NiO, and Cr2O3) endowed the sintered composites with low friction coefficient and wear rate. When the temperature was above 600 °C, the tribolayer containing monoclinic-SrAl4O7, orthorhombic-SrAl4O7 and oxides exhibited better tribological properties than the tribofilm consisting of monoclinic-SrAl4O7, SrAl12O19 and oxides. Furthermore, at 800 °C, the appearance of orthorhombic-SrAl4O7 on the worn surface led to a low friction coefficient and wear rate.

Penicillium digitatum is the primary pathogen causing the green mold of citrus. The need for the development of higher effective and lower toxic natural antifungal agents is urgent, owing to the lack of antifungal agents that can successfully combat P. digitatum. Herein, the effects and mechanisms of 2-methoxy-1,4-naphthoquinone (MNQ) as a potential inhibitor of P. digitatumwere studied. First, MNQ showed a significant anti-P. digitatum effect with a minimum inhibitory concentration value of 5.0 μg/mL. Then, transcriptome, proteome, and metabolome profiling were performed on the MNQ-treated P. digitatum. A total of 910 genes, 297 proteins, and 174 metabolites changed significantly. The omics analysis indicated that it could be seen that MNQ mainly inhibits the growth of P. digitatum by affecting the synthesis of branched-chain amino acids and cell walls. These findings will be a great contribution to the further understanding of the possible molecular action of MNQ.

The catalytic steam gasification of Yanzhou (YZ) bituminous coal char loading with K2CO3 and CaO was studied in a fixed bed with 20 mm in inner diameter. The influence of K2CO3 on caking properties of Yanzhou bituminous coal was investigated. The relationship between carbon conversion and reaction time and catalyst loading amount of Yanzhou coal char was measured from 700 to 850°C. The effects of reaction temperature and catalyst loading amount on molar yield of the gasification gas were studied. The influence of catalyst on the microstructure of the YZ coal char was determined. The results show that K2CO3 had significant effects of caking destruction and catalytic gasification on YZ coal. The carbon conversion of YZ coal char increased with the increase of gasification temperature and K2CO3 loading amount. The addition of CaO could improve the carbon conversion of char and promoted the generation of gasification gas to some extent. The molar yield of gasification gas increased with the increase of gasification temperature, and H2 increased the most. The 002 peak of YZ coal char became lower and wider, and moved towards the lower position with the addition of K2CO3 and thus decrease the graphitization trend.

When it comes to bonding in an aqueous environment, intertidal marine organisms such as mussels, sandcastle worms, barnacles and polychaetes are providing inspiration for the assembly of synthetic molecules into the polymeric adhesives. Although intense demands in various life or industrial applications and many mussel-inspired systems have been shown to develop coatings and hydrogels, exploring the mimetic mussel adhesive system through the control of composition and polymer molecular weight is demonstrated less often. In this report, we showed a simple approach to synthesize mussel-inspired adhesive, P(N-butyl acrylate-co-l-Dopa-methacrylate anhydride), which possesses characteristics of simple synthesis, easy-using, no extra-crosslinker need, and excellent adhesion behaviour on diverse substrates. Adhesion behaviour was examined using low- and high-surface-energy substrates (e.g. PTFE and steel, respectively). Furthermore, the fabricated adhesives exhibited excellent underwater adhesive behaviour for steel in various aqueous solutions, including ion ((IO4)− and Mn3+), acid and alkali solutions (pH = 4, 6.7 and 8, respectively). The outstanding fabricated adhesives take advantage of the catechol functionality and wettability of the resulting polymer. These insights should help us to design next-generation underwater adhesive systems as well as open up a number of future research designs for mussel-inspired adhesives with performance not accessed previously.

Weight reduction is often considered the primary goal in the development of structure materials. A new Ti-8Al-1Cr-1V-0.5Fe-0.1Si (wt.%) alloy with a low-density and a high-strength was developed in this work. The microstructures and mechanical properties of the alloy were investigated in hot-rolled and solution-aging (STA) treatment conditions. The microstructures of the alloy in both states consist of the spherical αp phase, acicular αs phase, and a small amount of β phase. Attributed to such heterogeneous microstructures, the hot-rolled alloy exhibits an outstanding tensile strength of 1046.1 MPa, a total elongation of ~8.3%, and an impressive low density of 4.23 g/cm3. After heat treatment, the alloy also exhibits a similar strength and ductility. A detailed analysis of the deformation modes shows that the numerous dislocations slippages and deformation twinning in the αp phase are the main reasons for the high ductility, and the acicular αs phase provides the alloy with high strength after heat treatment. This newly developed alloy is a potential material for various structural applications.

The carbon dissolving reaction is the main factor for the deterioration of coke in the blast furnace. Therefore, in order to investigate the effect of coke deterioration on the permeability of blast furnace, the Coke Pulverization Rate (CPR) which represented the degree of Matrix carbon loss after carbon dissolution was put forward in this paper. The results showed that the CPR increases with the increase of volatile of coal blending, ash content of coke, M10 and coke reactivity index (CRI), while decreases with the rising of M40 and coke strength after reactivity (CSR). Analysis of the production data of 5BF blast furnace of Meishan Steel showed that under the conditions of coke ash (Ad) 87%, CRI 66%, the CPR would be less than 23%, which is conductive to ensure stable permeability large blast furnace.

Mussel-inspired polymer has long been desired for the next generation high adhesion strength bioadhesives. However, the currently synthetic method of mussel-inspired polymer was based on the conventional thermal polymerization. A large majority of thermal polymerizations need solvents, these solvents present risk of environment pollution. Different from the existing methods, here we introduce a facile route for the fabrication of mussel-inspired adhesives via UV polymerization. Meanwhile, polycaprolactone (PCL) was incorporated to enhance biocompatibility and biodegradability of adhesives. The investigated mussel-inspired adhesives (poly (L-DMA-GPCL-MA)) were synthesized with 3,4-dihydroxyphenyl- l -alanine acrylamide (L-DMA) and glycerol-polycaprolactone acrylate (GPCL-MA) under UV exposure. We systematically evaluated the effect of L-DMA and GPCL-MA on the UV polymerization kinetics, mechanical properties, thermal stability, adhesion and degradable properties of resulting adhesives. Our findings reveal that poly (L-DMA-GPCL-MA) shows excellent adhesive behaviors, the maximum adhesion of polymer on steel substrate was 3.2 ± 0.38 MPa, More importantly, it is able to stick to the low-energy surface substrates including Polypropylene (PP) and Polytetrafluoroethylene (PTFE). Furthermore, poly (L-DMA-GPCL-MA) shows faster degradation, the polymer lost around 40% of their initial weight after 48 day immersing into PBS (0.01 M, pH = 7.3). Based on these properties, poly (L-DMA-GPCL-MA) shows promise as a potential bio-inspired degradable adhesive.

Pyrolysis of Shenfu long-flame coal at low temperature has been carried out in a tubular furnace to reduce the influence of the addition of non-caking coal on the caking property of coking coal. The influence of low temperature pyrolysis on the chemical composition and microstructure of Shenfu long-flame coal has been studied. Finally, the effect of low-temperature pyrolysis on the relative Giseeler fluidity and caking index has been investigated by mixing the Shenfu long-flame coal with Taozhuang fat coal in a certain proportion. The experimental results show that the active component content of Shenfu long-flame coal is slightly lower, while the inert component content increases slightly after low-temperature pyrolysis. The maximum mean reflectivity of Shenfu long-flame coal vitrinite group increases with the increase of final temperature of pyrolysis. The surface of long-flame coal tends to be dense and smooth, and the crystal structure of the Shenfu long-flame coal gradually changes to graphite crystal structure. Compared with the simple addition of long-flame coal to coking coal, adding long-flame coal after low-temperature pyrolysis can alleviate the weakening effect of adding non-cohesive material on the caking property of coking coal and therefore improve the quality of coke.

Heavy use by cars and trucks leads to huge damages, so road damage detection is an essential task to road maintenance. Traditional road damage detection has to require a huge amount of manual effort, it is therefore of great interest to propose vision-based systems that can automatically detect the road damages. In this work, we use deep learning models to detect road damages efficiently. Specifically, we apply a segmentation method to detect the road areas and build a road-interest map for the raw images. Then we adopt the state-of-the-art deep objective detection model including Faster-RCNN and YOLOv4 for completing detection. Experiments convey that the proposed model achieves good detection performance on the IEEE Global Road Damage Detection Challenge 2020.

In the paper, a three-phase Delta-Delta LLC resonant converter is introduced. Furthermore, the characteristics of resonant tank without or with phase-shedding are analyzed based on FHA method. Finally, the performance of a 16kW DC/DC converter designed for 750V input and 150V output is evaluated and peak efficiency up to 98.9% is implemented.

vehicle-mounted isolated bidirectional converter has gradually become the focus of train application research. In this paper, the main isolated bidirectional converter scheme is compared, the operation process of CLLC circuit is studied in detail, the resonance of soft switching stage is analyzed, and a parameter design method is proposed to ensure the realization of soft switching when the parameters of CLLC converter are different. A 20kW engineering prototype is built to verify the effectiveness of the method. At the same time, the efficiency of CLLC converter is verified with the efficiency of DAB scheme.

Objective: To investigate the diagnostic efficiency of truncal-type occlusion and branching-site occlusion in determining the etiology of intracranial large artery occlusion related acute ischemic stroke (AIS). Methods: Patients with intracranial large artery occlusion related AIS who received stent retriever (SR) thrombectomy from November 2014 to June 2019 were included in the study. All patients underwent angiography before SR thrombectomy, which was used to evaluate the occlusion type. Differences in the distribution of occlusion types in intracranial atherosclerosis (ICAS) and embolism were assessed, and the diagnostic indicators, including the area under the ROC curve (AUC), sensitivity, and specificity were calculated. Results: Of the 115 AIS patients with intracranial large artery occlusion, 42 were classified as having ICAS, and 73 having an embolism. In the ICAS group, branching-site occlusion was responsible for 3 (7%) cases and truncal-type occlusion for 39 (93%) cases, while in the embolism group, branching-site occlusion was responsible for 66 (90%) cases and truncal-type occlusion for 7 (10%) cases; the difference was statistically significant (all P < 0.01). The AUC for ICAS predicted by truncal-type occlusion was 0.916, with a sensitivity of 92.86%, and specificity of 90.41%. Conclusion: Truncal-type occlusion showed a high predictability of ICAS. Determine the etiology of intracranial large artery occlusion related AIS before SR thrombectomy may be most helpful in setting up optimal endovascular treatment strategies.

A triazine nitrogen-rich derivative fluorescent probe, 1,1’-(6-chloro-1,3,5-triazine-2,4-diyl)bis(1H-benzo[d][1,2,3]triazole)(L), has been synthesized and successfully achieved for the efficient detection for Fe3+, Cr2O72-, nitrobenzene as a turn-off chemosensor in DMF/H2O. The quenching constant(Ksv) and detection of limit for Fe3+, Cr2O72-, nitrobenzene on fluorescence response of the sensor can be as low as 470.00 M-1, 359.94 M-1, 3.62*103 mL-1, 2.10*10-5 M, 5.73*10-5 M, 1.24*10-5 mL, respectively. On the contrary, It is applied to detected for toluene and xylene as a turn-on chemosensor in DMF. The quenching constant and detection of limit for toluene and xylene on fluorescence response of the sensor can be as low as -11.05 mL-1, -6.23 mL-1, 9.30*10-4 mL, 7.35*10-3 mL, respectively. The application of water sample and vegetables showed that the L had high sensitive detection for Fe3+ ions. Meanwhile the application of gasoline, diesel and engine oil showed that the L had high sensitive detection for toluene and xylene.

In the area of pressure-sensitive adhesives (PSAs), acrylic PSAs have been successfully applied in many fields, including self-adhesive tapes, sign labels, carrier-free tapes, double-sided tapes and protective films, but applications of heat-resistant acrylic PSAs are relatively rare. In this study, the thermal stability of acrylic polymer containing maleimide (Mal) functional groups has been investigated. The PSAs were synthesized by acrylic monomers and Mal through copolymerization. The influence of Mal on the viscosity, molecular weight (Mw, Mn), glass transition temperature, thermogravimetric analysis and contact angle of acrylic PSAs was also studied. The adhesion performance and thermal stability of acrylic PSAs could be significantly enhanced by increase in Mal content of the synthesized resin. After 3 h of treatment in drying oven at 170 °C, the modified PSAs can be peeled (180°) off from the substrate without residues on substrate surface at room temperature, while the non-modified acrylic PSAs possessed residues after treatment from 110 °C. The maximum 180° peel strength of modified PSA films was 12.7 N/25 mm when the content of Mal was 7.5 wt%.

The dual active bridge (DAB) converter is widely used in different fields, such as electric vehicles, distributed power generation system, energy networks. it also can be introduced in railway applications to implement power electronic transformers, bidirectional battery chargers etc. The DAB converter is usually designed combining with series resonant to reduce the switching off loss. Nevertheless this will make it hard to achieve the zero voltage switching on of the primary power semiconductor at light load, especially when voltage conversion ratio is far away from one. Besides, the dead-time has great effect to the soft switching implementation. The voltage polarity reversal and voltage sag phenomena etc. are caused by the dead-time effect. This paper provides a precise mathematical transmission power model considering the resonant and dead-time effect respectively. A comprehensive theoretical analysis of the dead-time effect on the series resonant DAB converter is presented. By improving the dead-time, the soft switching rang is increased and the efficiency will be improved at light load. The experimental results are provided to verify the theoretical analysis.

In order to investigate the influence of coal blending with waste rubber on coke quality, the pyrolysis performance of rubber powder was analyzed, and the coking experiment of coal blending was carried out in 70 kg test coke oven. The experimental results showed that the pyrolysis range of waste rubber was similar to that of blended coal by analyzing the pyrolysis characteristics of waste rubber. The ash content (Ad), coke reactivity index (CRI) and coke strength after reactivity (CSR) would decrease, while the sulfur content (St, d) of coke would increase with the increasing of coal blending ratio of waste rubber. The specific surface area of coke increased from 1.5m2/g to 3.5m2/g, the Lc of coke microcrystalline structure and the degree of graphitization decreased gradually with increasing the ratio of waste rubber from 0% to 6% in coal blending. The optical structure of coke showed that the fine-grained mosaic structure increased and the degree of anisotropy of coke (OTI) decreased.

With the application of digital control system and field-bus technology in nuclear power plant, the production data has the trend of explosive growth. For the large amount of production data with the characteristic of high dimensional and multi-coupling, data mining technology will play an increasingly important role. This paper briefly introduces the data mining process and its commonly used methods. Based on the data size of conventional island in nuclear power plant and the current data application, this paper put forward the data mining application in Conventional Island (CI), and analysis the primary approaches and trends of the applications.

Synthetic conductive materials capable of self-healing have attracted increasing attention and have been developing rapidly because of their potential applications. Despite great achievements, there is a need to advance mechanical properties and reduce the time for healing simultaneously since the branch functionalities are limited and the polymer mobilities are poor in current devices. In this work, we report an effective and simple free radical polymerization approach to synthesize hydrogel using multi-vinyl-modified reduced graphene oxide (rGO) and acrylate monomers containing abundant polar groups. After enhanced by polar groups modified Cellulose Nanocrystal (CNC), the hydrogel exhibits extremely fast electronic self-healing ability and excellent repeatable restoration performance at 25 °C. The stress of hydrogel reaches 2.5 MPa and 1600% of elongation. The hydrogel recovers to its original mechanical and conductive properties within 12 s after cutting and maintains efficiency of nearly 99.3% of its original mechanical and conductive properties after 5 times of cutting and self-healing processes. The design of this conductive, room-temperature self-healing hydrogel takes unique advantage of supramolecular chemistry and polymer nanoscience and shed light on promising applications for self-healing electronics, artificial skins, soft robotics, biomimetic prostheses, and energy storage.

The perception of human behavior that is different from normal has always been a common concern in many fields. The widespread use of smartphones makes it possible to obtain a large amount of user activities at fine spatial scales. In this context, this article first systematically summarizes the research on human behavior patterns in the era of mobile phone big data. Although the current research has made certain research progress, there are certain limitations in data source selection and activity semantic analysis. Then it focuses on the relevant research on the perception of abnormal events by mobile phone positioning big data, including the research progress in abnormal event early warning and emergency response, and believes that there is more room for development in related research. The analysis of these studies provides reference value for handling similar emergencies in the future, especially for post-disaster emergency response and resource allocation. It provides strong theoretical support.

In the urban stock development stage, it is essential to clarify urban regeneration characteristics, market maturity, urban regeneration potential, and development direction of objective cities for enterprises. However, previous studies lack concrete analysis for the urban regeneration system and potential, particularly with respect to quantitative research. This study evaluated the urban regeneration decision making map of the core cities of the Pearl River Delta in China (Shenzhen, Guangzhou, Zhuhai, and Dongguan), including system analysis and potential space evaluation. For the system analysis, through the horizontal comparison of the four target cities' regeneration system based on the sustainability of local policies, it was found that Shenzhen has the highest degree of perfection of urban regeneration system, followed by Guangzhou, Zhuhai, and Dongguan. Especially in the three aspects of protecting public interests, reserving industrial development space, and urban sustainable development, Shenzhen has formulated a series of supporting urban renewal laws and regulations, with the most standardized urban renewal management and the most mature urban renewal market. For the potential space evaluation, the spatial factors affecting urban regeneration potential were selected for the superposition analysis to obtain the distribution and data characteristics of the target cities' regeneration potential with the Analytic Hierarchy Process. It was found that Dongguan has the highest proportion of high potential regeneration land, accounting for 29.4%, while Shenzhen has the lowest proportion of high potential regeneration land. Regarding the four objective cities, it is more difficult to carry out urban regeneration project in Shenzhen and Guangzhou due to complex control conditions and earlier projects’ accomplishment. The system of Zhuhai and Dongguan needs to be further adjusted in practice and there is a relatively more flexible space for these two cities. The current land development intensity in Dongguan far exceeds that in Zhuhai, and the demand for its urban renewal is more urgent. Therefore, this study suggests that Dongguan's urban regeneration market should become the focus of enterprises.

The effect of SrSO 4 content on the tribological properties of NiCr–30wt%ZrO 2 (Y 2 O 3 ) (NC30Z) cermet was evaluated over a wide temperature range from room temperature to 1000 °C. The results indicated that the inclusion of SrSO 4 effectively improved the friction coefficients and wear rates of NC30Z cermet above 400 °C. NC30Z–5SrSO 4 composite against alumina ball exhibited satisfactory tribological performance, which was attributed to synergistic lubrication of pseudocubic-SrZrO 3 and NiCr 2 O 4 between 400 °C and 800 °C and cubic-SrZrO 3 , NiCr 2 O 4 , NiO and Cr 2 O 3 at 1000 °C.

Adhesive hydrogels have significantly attracted scientific interest as a promising material for next-generation adhesive applications, such as tissue engineering, wound dressing, electronic skin sensor, and drug delivery. However, the acute defects of low mechanical property, limited adhesion and poor fatigue-resistant ability hinder their further applications, especially for low-surface energy materials. In this work, inspired by the advantages of cytosine from the basic units of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), the cytosine methacryloylchloride (CMA) was successfully introduced into the hydrogel and crosslink with glycerol-polycaprolactone-methacrylic anhydride (GPCL-MA) to obtain excellent mechanical, tough, adhesive and recyclable hydrogels. Surprisingly, the resultant hydrogel could repeatedly adhere to various solid materials (e.g., steel, aluminum, glass, ceramics, wood, PET and rubber) as well as skin. The maximum adhesive strength was 16.6 ± 0.38 KPa on the steel substrate, it also shows the superior capability of adhesion to the low-surface energy substrates (e.g., Polypropylene (PP) and Polytetrafluoroethylene (PTFE)). Furthermore, the hydrogel exhibited robust mechanical performance: 1065% (strain loading), 81.0 KJ/m3 (toughness), 6.3 MPa (tensile elastic modulus), and it could quickly recover its initial state after 6 cycles loading-unloading deformation. As a result, the obtained hydrogel shows promise for the future development of adhesive materials with outstanding mechanical properties and functionality simultaneously.

Investigations of gut microbial diversity among fish to provide baseline data for wild marine fish, especially the carnivorous coral reef fishes of the South China Sea, are lacking. The present study investigated the gut microbiota of four carnivorous coral reef fishes, including Oxycheilinus unifasciatus, Cephalopholis urodeta, Lutjanus kasmira, and Gnathodentex aurolineatus, from the South China Sea for the first time using high-throughput Illumina sequencing. Proteobacteria, Firmicutes, and Bacteroidetes constituted 98% of the gut microbiota of the four fishes, and 20 of the gut microbial genera recovered in this study represent new reports from marine fishes. Comparative analysis indicated that the four fishes shared a similar microbial community, suggesting that diet type (carnivorous) might play a more important role in shaping the gut microbiota of coral reef fishes than the species of fish. Furthermore, the genera Psychrobacter, Escherichia-Shigella, and Vibrio constituted the core microbial community of the four fishes, accounting for 61&ndash, 91% of the total sequences in each fish. The lack of the genus Epulopiscium in the four fishes was in sharp contrast to what has been found in coral reef fishes from the Red Sea, in which Epulopiscium was shown to be the most dominant gut microbial genus in seven herbivorous coral reef fishes. In addition, while unique gut microbial genera accounted for a small proportion (8&ndash, 13%) of the total sequences, many such genera were distributed in each coral reef fish species, including several genera (Endozoicomonas, Clostridium, and Staphylococcus) that are frequently found in marine fishes and 11 new reports of gut microbes in marine fishes. The present study expands our knowledge of the diversity and specificity of gut microbes associated with coral reef fishes.

A new large intelligent mowing robot based on four wheeled mobile robot structure is proposed in the paper. Trajectory tracking control is a key factor for high efficiency of mowing robot. Firstly, the kinematics model of the intelligent mowing robot is established by Ackerman model in order to solve the trajectory tracking problem. Subsequently, the trajectory tracking algorithm based on BP neural network is designed, which is used to solve the nonlinear problem of trajectory tracking. Finally, the kinematics model and trajectory tracking algorithm are simulated by MATLAB. The simulation experiment results prove that trajectory tracking algorithm is effective.

Nowadays, spam is pervasive in the mailbox, and not only caused a waste of network resources, but also brings a lot of trouble to people's daily life. How to filter spam quickly and accurately is a challenge we are facing. For handling this challenge, this paper proposes a fast content-based spam filtering algorithm with fuzzy-SVM and k-means. First, K-means clustering algorithm is used to compress data with retain most of the effective information. Then, fuzzy support vector machine is used to train classification model, in order to deal with uncertain factors better. The experimental results show that this algorithms could improve the spam filtering speed and filtering accuracy rate effectively.

Multiple input multiple output (MIMO) can significantly improve the performance of wireless communication system due to transmission diversity and channel multiplexing. However, because of the use of massive antennas, both enabling technologies suffer from severe interference effects and energy loss problem, especially known as interference between users and energy dissipation caused by transmitter antenna at base station. In this paper, a practical cooperative eliminated interference mechanism is proposed for MIMO wireless communication system. We use the water-filling power algorithms to deal with the energy loss problem at the downlink transmitter. And then we combine the liner precoding algorithm with water-filling power algorithm, to solve the interference effects between users. We take the zero forcing (ZF) precoding algorithm and the maximum message leakage ratio (SLNR) precoding algorithm as an example to study this cooperative eliminated interference mechanism. The design is based on the key observation which is the system capacity and bit error rate. Simulation results show that this cooperative mechanism can improve the system performance better than precoding algorithm and water-filling power algorithm, which are executed individually. In addition, we can find that combining SLNR with water-filing power algorithm improves the system performance better than ZF algorithm.

The conjugate addition reactions of four organolithium reagents to 2,3,4,5-tetraphenylcyclopentadienone (tetracyclone) were investigated to reveal the reactivity of organolithium reagents to tetracyclone. The results show that 1,2-addition products 2,3,4,5-tetraphenyl-1-(2-thienyl)-2,4-cyclopentadien-1-ol(1), 1-n-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol(2) and 1,2,3,4,5-pentaphenyl-2,4-cyclopentadien-1-ol(3) were synthesized in excellent yields while tetracyclone reacted with 2-thienyllithium, n-butyllithium and phenyllithium, respectively. Interestingly, three 1,2-, 1,4- and 1,6-addition isomers 1-tert-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol(4), 4-tert-butyl-2,3,4,5-tetraphenyl-2-cyclopenten-l-one(5) and 2-tert-butyl-2,3,4,5-tetraphenyl-3-cyclopenten-l-one(6), were simultaneously obtained by the conjugate addition reaction of tert-butyllithium with larger steric hindrance to tetracyclone. Compounds 1—6 were characterized by 1H and 13C NMR spectra, Fourier transform infrared(FTIR) spectra and mass spectra(MS). The crystal and molecular structures of compounds 1, 2 and isomers 5, 6 were determined by X-ray single crystal diffraction technique. The results imply that the steric hindrance of tert-butyllithium probably play a key role in controlling the conjugate addition reaction. The conjugate addition mechanism of organolithium reagents to tetracyclone was proposed.

In this paper, a switched Kalmanfilter (KF) is used to predict the status of feature points leaving the field of view (FOV), which is one of the most common constraints in FOV. By using the prediction of status to compensate for the real state of feature points, nonholonomic robots conduct visual servoing tasks efficiently. Results of simulation and experiments verify the effectiveness of the proposed approach.

The power quality of grids has been influenced by the mounting number of asymmetric loads. Recently, the three-phase four-leg inverter which adds a bridge to three-phase three-bridge inverter has been researched because of the merit of the compact structure, small bulk and high efficiency. The three-phase four-leg inverter has subsequently brought vigor into the power system with broad application prospects but its control method becomes much more complex than ever and difficult to achieve. Therefore, a new control method has been proposed in this paper based on positive feedback of current control and three-dimensional space vector modulation (SVM). Through analyzing the four-leg inverter system, three-phase unbalanced current is introduced from the three-phase voltage feedback control. Furthermore, the amount of imbalance is increased through positive feedback in order to control the balanceness of three-phase output voltage more quickly and accurately. The simulation showed the feasibility and effectiveness of the method proposed in this paper.

Phosphorus is the most important limiting factor in nutrient cycling.It is also the key element controlling primary production in aquatic environments.Sediments act as both a sink and a source of phosphorus because of continuous transport of phosphorus species across the sediment-water interface.Phosphorus is intimately involved in both the terrestrial and marine biogeochemical cycles.However,not all fractions of phosphorus in sediments are released to the overlying water.Therefore the effects of phosphorus in sediments in promoting aquatic environment eutrophication can be more efficiently evaluated by studying phosphorus fractions,rather than total phosphorus(TP).In this study,the forms and bioavailability of phosphorus in the sediment were analyzed by means of SEDEX(Ruttenberg KC) to determine the geochemical characteristics of phosphorus in the Huang Dong Hai continental shelf.According to this method,there are five types of phosphorus: iron-phosphorus(Fe-P),organic-phosphorus(Or-P),detritus-phosphorus(De-P),exchangeable-phosphorus(Ex-P),and autologous-phosphorus(Au-P).They differ from each other in occurrence,origin and geochemical features.The horizontal and vertical distribution of six forms is presented.The profiles of age deposition were also investigated to reveal changes in the contents of the different phosphorus forms over about two hundred years.The rank order of the contents of phosphorus fractions in the surface sediment was Au-P(140.72 μg/g) De-P(59.23 μg/g) Or-P(32.69 μg/g) Fe-P(29.91 μg/g) Ex-P(5.92 μg/g).The contents of Au-P and Or-P decreased from offshore to the open sea,and values for De-P were uniformly distributed over the whole sea area.High contents of TP and Ex-P were present in the Yangtze estuary area.TP,Fe-P,Or-P,De-P,Au-P and Ex-P contents in the sediments were in the range 310.23—941.78μg/g,5.46—58.11μg/g,4.87—80.57μg/g,12.68—282.15μg/g,31.86—271.38μg/g,and 1.32—20.95μg/g,respectively.The vertical distribution of the different fractions of phosphorus at four sampling stations varied.The distribution of different phosphorus fractions in different sediments reflected changes in the early diagenesis of phosphorus.The concentration of Au-P in H1-18 was much lower than at the other three stations.In the study area,the relative contributions of Fe-P,Ex-P,and Or-P were 5.96%,1.18%,and 6.51% of TP,respectively.Fe-P is considered to be the most labile fraction of phosphorus fraction in the sediments.It will change when the oxidation-reduction environment changes in the surface sediments.Fe-P can be used to determine the source of phosphorus and indicate the extent of environmental pollution.Or-P can be released during the decomposition of organic matter in the early diagenetic process,and even convert to other forms of phosphorus.When organic matter degrades,the phosphorus is released into the overlying water.Consequently,the degradation of Or-P is an important process in its influencing of the contents of phosphorus fractions in sediments.Ex-P is influenced by particle size of the sediments and released into the overlying water mainly through ion exchange.Hence it is important to understand under what conditions phosphorus can be changed from one fraction into another and phosphorus in sediments can be released into the overlying water.Fe-P,Ex-P,and Or-P are biologically available fractions of phosphorus in our study area.The results showed that potentially biological available phosphorus accounted for 13.55% of the total phosphorus.