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A facile photocatalytic radical [4+2] cyclization of N-aryl-α-amino acids with various alkenes to access structurally polysubstituted tetrahydroquinolines has been developed. Using a simple bipyridine as a catalyst, different N-aryl-α-amino acids could be utilized as the radical precursors to react with diverse electrophilic alkenes, including exocyclic terminal alkenes, acyclic terminal alkenes, and cycloalkenes, producing 10 types of nitrogen-containing heterocyclic compounds fused in multiple frameworks in generally moderate yields with good diastereoselectivities. Scale-up synthesis and transformations of the products further demonstrated the synthetic application of this protocol. Moreover, a decarboxylative radial pathway via a proton-coupled electron transfer process for illustration of this [4+2] cyclization was proposed on the basis of the control experiments. This process is highlighted by a simple bipyridine photocatalysis, mild reaction conditions, various N-aryl-α-amino acids and alkene materials, and application for the modification of natural products.

To better measure the fault tolerance and reliability of a network, Yuan et al. introduced the non-inclusive g-good-neighbour diagnosability of a network. The g-good-neighbour faulty set is a special faulty set, which satisfies that every fault-free vertex has at least gfault-free neighbours. The non-inclusive g-good-neighbour diagnosability requires every pair of g-good-neighbour faulty sets is non-inclusive, denoted as $ t_{Ng}(G) $ tNg(G). In this paper, we study the non-inclusive g-good-neighbour diagnosability of hypercubes and obtain $ t_{Ng}(Q_{n})=(n-1-g)2^{g+1}+2^{g}-1 $ tNg(Qn)=(n−1−g)2g+1+2g−1for $ g\in \{1,2\} $ g∈{1,2}under the PMC model, $ t_{N1}(Q_{n})=3n-5 $ tN1(Qn)=3n−5, $ t_{N2}(Q_{n})=8n-21 $ tN2(Qn)=8n−21under the MM* model.

The humidity influence on the electronic and ionic resistance properties of thin post-treated poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films is investigated. In particular, the resistance of these PEDOT:PSS films post-treated with three different concentrations (0, 0.05, and 0.35 M) of ethyl-3-methylimidazolium dicyanamide (EMIM DCA) is measured while being exposed to a defined humidity protocol. A resistance increase upon elevated humidity is observed for the 0 M reference sample, while the EMIM DCA post-treated samples demonstrate a reverse behavior. Simultaneously performed in situgrazing-incidence small-angle X-ray scattering (GISAXS) measurements evidence changes in the film morphology upon varying the humidity, namely, an increase in the PEDOT domain distances. This leads to a detriment in the interdomain hole transport, which causes a rise in the resistance, as observed for the 0 M reference sample. Finally, electrochemical impedance spectroscopy (EIS) measurements at different humidities reveal additional contributions of ionic charge carriers in the EMIM DCA post-treated PEDOT:PSS films. Therefrom, a model is proposed, which describes the hole and cation transport in different post-treated PEDOT:PSS films dependent on the ambient humidity.

ABSTRACT High strength ternary binder based on ordinary Portland cement (OPC), calcium aluminate cement (CAC) and calcium sulfate (CS) is used as repair materials. However, temperature and humidity govern the [...]

A novel and practical synthesis of mavorixafor (1) is reported. The novelty of this synthetic route is the use of 8-chloro-5,6,7,8-tetrahydroquinoline (9) and 1,4-diaminobutane as the materials, instead of 8-amino-5,6,7,8-tetrahydroquinoline (4) and N,N-diprotected aminobutyraldehyde (6aor 6b). The preparation of (S)-8-(4-aminobutylamino)-5,6,7,8-tetrahydroquinoline (13) by resolution with N-acetyl-l-leucine was first achieved. Then the one-pot synthesis of 1from 13involving protection, condensation, and subsequent hydrolysis was successfully developed. In addition, the final product with a satisfactory purity (>99.5%, detected by both achiral and chiral HPLC) was obtained by a simple operation (salification) without column chromatographic purification.

Storm surges are cataclysmic natural disasters that occur along the coasts and are usually accompanied by large waves. The effects of coupled storm surges and waves can pose a significant threat to coastal security. Previous laboratory studies on the effects of storm surges and waves on coastal structures have typically utilized steady water levels and constant wave elements. An indoor simulation of the coupled processes of tides and waves is developed by adding a tide generation system to an existing laboratory wave basin to model continuous dynamic tide levels so that tide generation and wave-making occur synchronously in the pool. Specific experimental methods are given, which are applied to further study waves overtopping on artificial sea dikes and coastal flooding evolution under the coupled actions of tides and waves. The results of the overtopping discharge obtained by the test with a dynamic water level are compared with those obtained from steady water level tests and the existing empirical formula. In addition, the impacts of ecological coastal shelterbelts and structures on coastal flood processes and distributions are also investigated. The proposed simulation methods provide a new approach for studying the effects of storm surges and waves on coastal areas. The study also aims to provide a reference for coastal protective engineering.

With the increasing construction of artificial beach in coastal areas, it is of practical significance to study the beach surface deformation of artificial beach profile. Previous studies only focus on a single wave dynamic factor, and it is difficult to predict the beach deformation of artificial beach profile under the storm surge—wave co-action. To solve this problem, the cross-section physical model test method was used to study the beach surface deformation of a typical artificial beach profile in Shuangdao Bay, Weihai, Shandong Province, after continuous wave actions till they stabilize. The characteristics of beach surface deformation under the conditions of constant water levels, ladder-shaped water level combined with corresponding wave elements and storm surge—wave co-action are compared and analyzed. A beach profile model which satisfies the theory of Bruun model is proposed. The test results show that the maximum scour depth of beach under storm surge—wave co-action is smaller and the scour range is obviously larger than that under the condition of constant water levels or ladder-shaped water level. The evaluation of the maximum scour depth by traditional model test tends to be conservative while the evaluation of the scour range is insufficient. The research results can provide scientific reference for designing artificial beaches.

Mesoporous hematite (α-Fe2O3) thin films with high surface-to-volume ratios show great potential as photoelectrodes or electrochemical electrodes in energy conversion and storage. In the present work, with the assistance of an up-scalable slot-die coating technique, locally highly ordered α-Fe2O3thin films are successfully printed based on the amphiphilic diblock copolymer poly(styrene-b-4-vinylpyridine) (PS-b-P4VP) as a structure-directing agent. Pure PS-b-P4VP films are printed under the same conditions for comparison. The micellization of the diblock copolymer in solution, the film formation process of the printed thin films, the homogeneity of the dry films in the lateral and vertical direction as well as the morphological and compositional information on the calcined hybrid PS-b-P4VP/FeCl3thin film are investigated. Because of convection during the solvent evaporation process, a similar dimple-type structure of vertically aligned cylindrical PS domains in a P4VP matrix developed for both printed PS-b-P4VP and hybrid PS-b-P4VP/FeCl3thin films. The coordination effect between the Fe3+ions and the vinylpyridine groups significantly affects the attachment ability of the P4VP chains to the silicon substrate. Accordingly, distinct feature sizes and homogeneity in the lateral direction, as well as the thicknesses in the perpendicular direction, are demonstrated in the two printed films. By removing the polymer template from the hybrid PS-b-P4VP/FeCl3film at high temperature, a locally highly ordered mesoporous α-Fe2O3film is obtained. Thus, a facile and up-scalable printing technique is presented for producing homogeneous mesoporous α-Fe2O3thin films.

ABSTRACTThe aim of this study was to determine the diversity of intestinal microflora and its correlation with clinical parameters in diabetic patients and healthy subjects and to assess the importance of intestinal flora in patients with diabetes. Forty-four patients with diabetes were included. The control group included 47 healthy people. Their data, biochemical indicators and results from 16S rRNA sequencing of their fecal samples were collected. Compared with the healthy population, the intestinal flora of the diabetic patients was obviously abnormal. Within the diabetes group, the abundances of the genera Faecalibacterium, Prevotella, and Roseburia were higher, and the abundances of the genera Shigella and Bifidobacterium were lower. In the correlation analysis between bacteria and clinical indicators, it was found that the genera Veillonella and unclassified_Enterobacteriaceae were negatively related to blood glucose, while the genera Phascolarctobacterium, unidentified_Bacteroidales and Prevotella were significantly positively correlated with fasting blood glucose. Twelve microbial markers were detected in the random forest model, and the area under the curve (AUC) was 84.1%. This index was greater than the diagnostic effect of fasting blood glucose. This was also supported by the joint diagnostic model of microorganisms and clinical indicators. In addition, the intestinal flora significantly improved the diagnosis of diabetes. In conclusion, it can be concluded from these results that intestinal flora is essential for the occurrence and development of diabetes, which seems to be as important as blood glucose itself.Abbreviations:PCoA: principal coordinate analysis; NMDS: non econometric multidimensional scaling analysis; LEfSe: linear discriminant analysis effect size; LDA: linear discriminant analysis; POD: probability of disease; BMI: body mass index; DCA: decision curve analysis

Realization of multi-source energy harvesting with one single device would maximize power output. Thus, it is emerging as a promising strategy towards renewable energy generation and has attracted worldwide attention in the past decades. Capable of capturing mechanical energy that is ubiquitous in the ambient environment, triboelectric nanogenerator (TENG) has been considered a novel yet effective source towards next-generation energy harvesting. In this work, a flexible hybrid energy harvester (HEH) is developed viathe rational integration of autonomous self-healing TENG and high bending-stable lead sulfide quantum dot (PbS QD) solar cell, enabling independent electricity generation by two different mechanisms. The single-electrode mode TENG component with self-healing is realized by a polydimethylsiloxane/Triton X-100 (PDMS/TX100) mixture as the dielectric layer and the shared gold (Au) electrode, which generates 0.39µA of output current (Iout), 24.6V of output voltages (Vout), 15.4 nC of transfer charges (Qsc), and 7.80mWm-2of output power peak density. The thin-film solar cell component is based on a PbS QD layer as the light absorber with a planar structure fabricated under low-cost and compatible conditions, achieving 22.8mAcm-2of short-circuit current density (Jsc) and 4.92% of power conversion efficiency (PCE). As a proof of concept, an electronic watch is successfully powered by harnessing ambient mechanical and solar energy with a hybridized energy cell. This approach will offer more opportunities to construct a versatile platform towards remote monitoring and smart home systems.

Interstitial flows in breakwater cores and seabeds are a key consideration in coastal and marine engineering designs and have a direct impact on their structural safety. In this paper, a unified fully coupled model for wave-permeable breakwater-porous seabed interactions is built based on an improved N-S equation. A numerical wave flume is constructed, and numerical studies are carried out by applying the finite difference method. In combination with a physical model test, the accuracy of the numerical simulation results is verified by comparing the calculated and measured values of wave height at measurement points and the seepage pressure within the breakwater and seabed. On this basis, the characteristics of the surrounding wave field and the internal flow field of the pore structure, as well as the evolution process of the fluctuating pore water pressure inside the breakwater and seabed, are further analyzed. The spatial distribution of the maximum fluctuating pore water pressure in the breakwater is compared between two cases by considering whether the seabed is permeable, and then the effect of seabed permeability on the dynamic pore water pressure in the breakwater is clarified. This study attempts to provide a reference for breakwater design and the protection of nearby seabeds.

In situprinting gives insight into the evolution of morphology and optical properties during slot-die coating of active layers for application in organic solar cells and enables an upscaling and optimization of the thin film deposition process and the photovoltaic performance. Active layers based on the conjugated polymer donor with benzodithiophene units PBDB-T-2Cl and the non-fullerene small-molecule acceptor IT-4F are printed with a slot-die coating technique and probed in situwith grazing incidence small-angle X-ray scattering, grazing incidence wide-angle X-ray scattering, and ultraviolet/visible light spectroscopy. The formation of the morphology is followed from the liquid state to the final dry film for different printing conditions (at 25 and 35 °C), and five regimes of film formation are determined. The morphological changes are correlated to changing optical properties. During the film formation, crystallization of the non-fullerene small-molecule acceptor takes place and polymer domains with sizes of some tens of nanometers emerge. A red shift of the optical band gap and a broadening of the absorbance spectrum occurs, which allow for exploiting the sun spectrum more efficiently and are expected to have a favorable effect on the solar cell performance.

ABSTRACTChronic wasting disease (CWD) is caused by prions, infectious proteinaceous particles, PrPCWD. We sequenced the PRNPgene of 2,899 white-tailed deer (WTD) from Illinois and southern Wisconsin, finding 38 haplotypes. Haplotypes A, B, D, E, G and 10 others encoded Q95G96S100N103A123Q226, designated ‘PrP variant A.’ Haplotype C and five other haplotypes encoded PrP ‘variant C’ (Q95S96S100N103A123Q226). Haplotype F and three other haplotypes encoded PrP ‘variant F’ (H95G96S100N103A123Q226). The association of CWD with encoded PrP variants was examined in 2,537 tested WTD from counties with CWD. Relative to PrP variant A, CWD susceptibility was lower in deer with PrP variant C (OR = 0.26, p< 0.001), and even lower in deer with PrP variant F (OR = 0.10, p< 0.0001). Susceptibility to CWD was highest in deer with both chromosomes encoding PrP variant A, lower with one copy encoding PrP variant A (OR = 0.25, p< 0.0001) and lowest in deer without PrP variant A (OR = 0.07, p< 0.0001). There appeared to be incomplete dominance for haplotypes encoding PrP variant C in reducing CWD susceptibility. Deer with both chromosomes encoding PrP variant F (FF) or one encoding PrP variant C and the other F (CF) were all CWD negative. Our results suggest that an increased population frequency of PrP variants C or F and a reduced frequency of PrP variant A may reduce the risk of CWD infection. Understanding the population and geographic distribution of PRNPpolymorphisms may be a useful tool in CWD management.

We compared methods commonly used in the field of river otter (Lontra canadensis) ecology to estimate visitation rates. We evaluated visitation rates estimated from 2 survey protocols based on video detection—individual visitation rate (IVR) and recording visitation rate (RVR)—and one indirect method based on scat detection—scat visitation rate (SVR). From August 2011 through August 2012, overall scat detection and cumulative video data from 403 camera‐days in 2 latrine sites (River and Pond, at a study site adjacent to the Salt Fork of the Vermilion River near Fairmount, Illinois, USA) located <50 m apart did not reveal monthly or seasonal differences between SVR and video detection methods. We identified positive correlations among the 3 visitation rates and differences between overall IVR and RVR. All 3 methods resulted in peak visitation rates during winter. However, when these data were stratified by latrine site, we found both positive and negative correlations at the River latrine. Our work supports that SVR, IVR, and RVR are valuable methods to estimate otter visitation rates at latrine sites. However, it is clear that even within such a short distance between these 2 latrines, these methods detected differences in site utilization. The significant positive correlation observed between IVR and RVR (overall and by latrine site) suggests these methods can be used interchangeably. Otter detection using SVR may serve as a complementary assessment tool for IVR and RVR. To optimize cross‐study comparisons and interpretation of results, future studies should detail the type of otter detection and visitation rate used, how variables are measured, formulas used in the calculation of the visitation rates, and detailed descriptions of scat counting efforts when using scat as a tool to evaluate otter visitation rates. © 2019 The Authors. Wildlife Society BulletinPublished by Wiley Periodicals, Inc. Different survey techniques used to estimate river otter visitation rates at latrine sites make it difficult to compare and extrapolate results among studies. We compared 3 of these survey techniques using a single dataset; although our results indicate that the 3 methods provide reliable otter activity information and 2 methods are interchangeable, we confirm the value of reporting detailed methodological descriptions for effective comparisons across studies.

Textile-reinforced composite (TRC) is a new material composed of finely grained cement-based concrete and textile grids, which can be a substitute for fiber-reinforced polymer (FRP) in strengthening applications. The diversity of the textile grid results in a difference in bond behaviors at the textile–matrix interface, which influences the tensile properties of TRC. Several researchers have investigated the tensile behaviors of TRC, mainly concentrating on the matrix strength, the content of short synthetic fibers, and the number of textile grids; discussions on the textile grid geometry, especially the coupling effect between the textile grid form and matrix category, remained limited. Therefore, this paper focuses on the effects of three carbon textile grids on the tensile behavior of TRC through a uniaxial tensile test; the design parameters also include the textile reinforcement ratio and matrix category. Twenty-seven groups of tensile samples were manufactured to investigate the effect of each variable on the crack distribution, failure pattern, stress–strain curve and characteristic parameter. The test results showed that flattening the roving diameter and especially thinning the coating depth ameliorated the matrix-to-textile permeability, and consequently improved the tensile mechanical properties of TRC. The enhancement level of tensile strength by increasing the textile reinforcement ratio was lower than that by optimizing textile grid form. In terms of different textile grid forms, the effect of the matrix category on the tensile performance of TRC showed significant differences. Finally, an analytical model is presented to forecast the stress–strain behavior of TRC with textile rupture failure.

In this paper, domestic and abroad research progresses and related calculation formulae of the mean overtopping discharge are summarized. Through integral physical model experiments, the relation between the wave direction and the overtopping discharge on the top of the sloping dike is focused on and put into analysis and discussion; and a modified formula for mean overtopping discharges under oblique irregular waves is proposed. The study shows that the mean overtopping discharge generally goes down as the relative wave obliquity βincreases for a fixed measurement point and the mean overtopping discharge generally increases as the wave steepness H/Ldecreases (the cycle increases) for a fixed relative wave obliquity.

5-Fluoro-1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridine-3-carbonitrile (9) was a key intermediate for the preparation of vericiguat (1). A new approach for the synthesis of 9was developed from 2-chloro-5-fluoronicotinic acid (22), a commercially available material, in an overall yield of 48.3%. The hydrazinolysis and intramolecular substitution were completed in one step to obtain 5-fluoro-1H-pyrazolo[3,4-b]pyridin-3-ol (26). N-1 benzylation of 26afforded 5-fluoro-1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridin-3-ol (27), whose structure was confirmed by 1H and 13C NMR spectroscopy, mass spectrometry, and single-crystal X-ray crystallography. Pd-catalyzed cyanation of 5-fluoro-1-(2-fluorobenzyl)-3-bromo-1H-pyrazolo[3,4-b]pyridine (28) was applied to prepare key intermediate 9. In the route, compounds 26, 27, and 28have not been reported in the previous literature.

The interaction between waves and porous breakwater has an important theoretical significance and great application value of engineering. In this paper, the tests of the core material’s influence in rubble mound breakwater on wave propagation are carried out. The relations among the transmitted wave height, incident wave element, and breakwater width are discussed. The calculation formula is obtained. The test results show that different core materials have obvious influence on wave propagation.

•What is already known on this subject? Ultrasound and vibration controlled transient elastography (VCTE) are more commonly used for non-alcoholic fatty liver disease (NAFLD) screening.•What are the new findings? VCTE can identify participants who were older, fatter, had a worse metabolic and biochemical profile when compared with ultrasound.•How might it impact on clinical practice in the foreseeable future? VCTE is suggested as a more practical non-invasive tool for the screening and follow-up of NAFLD in China.

Genotypes produced from plant breeding programs for annual crops are evaluated in multiyear, multilocation field trials where a large number of genotypes grown in a few locations in the first year are progressively reduced by selection and tested in a greater number of locations in successive years. Provided fixed resources are specified, the efficiencies of testing strategies differing in the number of locations and replications used and in the number of genotypes tested in successive years can be evaluated by three statistics (genetic repeatability, acceptance probability, and potential gain) calculated from five variance components applicable to the field trials. The five variance components required are deployed genetic variance, genotype‐by‐year, genotype‐by‐location, and genotype‐by‐year‐by‐location interaction variances and the residual (error) variance. Strictly, known variance components are required, but the statistics and their standard errors can be calculated using robust estimates of the variance components obtained from a combined analysis over years of a large set of historical data from field trials that are connected by shared genotypes across years, as genotype‐by‐year and genotype‐by‐year‐by‐location variance components are estimable. Single‐year analyses are unsuitable, as no estimate of the interactions with year are available, and such analyses produce biased estimates of genetic variance and genotype‐by‐location interaction variance. These procedures are illustrated using an example from the CIMMYT international wheat breeding program to evaluate 2‐yr testing strategies for CIMMYT's Elite Spring Wheat Yield Trials that has been distributed and evaluated internationally since 1979.

The host-guest inclusion complex formation between 3, 3’-benzidine/β-cyclodextrin derivative (BDCD) and pesticide carbendazim was studied and characterized by TEM and XRD. The result showed that inclusion complex had hydrophobic small-molecule fluorophores. The fluorescence titration was performed to calculate binding constant, sensitivity factor and limit of detection of the resulting complex. Based on the enhancement of the fluorescence intensity of carbendazim produced throught complex formation, a new sensitive method for the determination of carbendazim was established. A linear relationship was obtained between the fluorescence intensity and carbendazim concentration in the range of 3.57 and 17.83 μmol/L. The correlation coefficient, the lowest limit of detection and RSD were 0.9916, 15.51 nmol/L and 2.13%, respectively. This method has better anti-interference ability and stability. The proposed method have been successfully applied to the determination of carbendazim pesticide residues in water, vegetable and fruit samples with satisfactory results, recoveries in the range of 87.56 % to 104.04 % were obtained.

The inclusion complex formation between fluorescent sensor 3, 3’-benzidine/β-cyclodextrin derivative (BDCD) and pesticide carbaryl was studied and characterized by TEM, XRD and fluorescence spectroscopy. The stability constant and the stoichiometry of complex were determined. Based on the enhancement of the fluorescence intensity of carbaryl produced through complex formation, a new sensitive method for the determination of carbaryl was established. The linear relationship between the fluorescence intensity and carbaryl concentration was obtained in the range of 0.60-3.00 μmol/L with a correlation coefficient of 0.9946. The detection limit was 5.12 nmol/L. This method has been successfully applied to the determination of carbaryl pesticide residue in water, fruit and vegetable samples with satisfactory results, recoveries in the range of 94.12 % to 105.88 % were obtained. The method is rapid, simple, direct, economical, sensitive and useful for carbaryl analysis.

With the rapid development of social economy, the shortage of resources and the increasingly serious environmental pollution, the human society sustainable development problems become the focus of the world. Governments have issued the circular economy and environmental protection legislation. Reverse logistics gradually get concern and attention. Reverse logistics can be achieved through the manufacturers mode, the cooperation mode and the third party mode. This paper established mathematical model and compared research of the three modes under government surveillance, and to analyze of the impact of different recovery mode of the appliance industry Reverse Logistics.

Prediction of cardiovascular disease (CVD) is important in clinical practice. Machine learning (ML) may offer an improved alternative to current CVD risk stratification in individual patients. We aim to identify important predictors and compare ML models with traditional models according to their prediction performance in a large long-term follow-up cohort.

The isolation system between the upper structure and the foundation could reduce the seismic response of the former. A system combined of sliding and lead rubber bearings (LRB) is more effective in seismic isolation than using the later alone. In this research, the seismic responses of a building which was set with LRB and a combined system (the proportions between the sliding and LRB were 1/6, 1/4 and 1/3) respectively were analyzed and compared to that of the building without base isolation system to investigate the effect of seismic isolation. The relationship between isolation coefficient and the proportion of bearings was studied. The results show that the combined system could reduce the seismic response of structure, and it is more effective in seismic isolation if the leading bearing is relatively more.

Cracking of the cover concrete due to steel corrosion is considered as one of the major issues of durability of reinforced concrete (RC) structures. Numerous models have been developed to predict the time from corrosion initiation to cracking of the cover concrete. However, little work has been done on the effects of stirrup on reinforcement corrosion-induced cover cracking. In this paper, the effects of stirrup on reinforcement corrosion-induced cover cracking are investigated. The results of four short columns (section size 100×100 mm, total length 515 mm) subjected to accelerated corrosion clearly show that stirrups not only can effectively postpone and prevent the longitudinal crack initiation but also can restrict the width of cracks caused by corrosion of reinforcement. Therefore, prediction models should account for the effects of stirrup on reinforcement corrosion-induced cover cracking, and even the effects of load on it.

ZrB2-SiC ultra-high temperature ceramics (UHTCs) were pressureless sintered with Y2O3-Al2O3 as the sintering additives. The effects of sintering additive and crystallization annealing on the microstructure and properties of ZrB2-SiC UHTCs were investigated. Sintering was activated by producing liquid phase of Y2O3 and Al2O3. The relative density of sintered ZrB2-20wt%SiC ceramic could reach 96% when the content of sintering additive was 6% and the sintering temperature was 1750ºC and its bending strength, Vickers hardness, and fracture toughness were 412 MPa, 13 GPa, and 6.0 MPa•m1/2, respectively. The crystallization annealing can result in YAG phase from grain boundary and enhance the high temperature properties of the UHTCs. The UHTCs have excellent ablation resistance at ultra-high temperatures, and a very low ablation rate of 0.0006 mm/s after ablation for 900s at 2800ºC.

The sections of Φ55mm silicon nitride balls, sintered by gas pressure sintering were analyzed. The results show that temperature gradient during of the sintering process from the surface to the core of large size silicon nitride balls occurred because of the lower thermal conductivity of Si3N4. With the diameter increasing, the temperature gradient was more visible. The impurity of raw materials, such as free Si, free C and other metal oxides, like the SiO2 could produce gas, such as SiO, CO and so on, during the sintering process through the thermodynamic analysis. The producing gas exhausted more difficultly with the diameter of silicon nitride balls increasing. These factors were the most important to the defects of large size silicon nitride balls during the sintering process and made cracks and crescent on the surface of balls.

High-purity alumina ceramics were prepared by sintering at low temperature, using rare earth oxide Y2O3 and Tm2O3 as sintering aids. Adding the mixture of Y2O3 and Tm2O3 in the alumina powders can effectively improve the sintering ability and mechanical properties. The mixture, Y2O3+Tm2O3, can restrain the grains growth, fine the grain size, make the grain uniform and finally help to form compact structure. The transgranular fracture was the main fracture mode. It was found the relative density of alumina ceramics with 0.3wt% Y2O3 and Tm2O3, sintered at 1620°C for 3hrs, can be over 99.2% and the strength, toughness and microhardness reach 533.1MPa, 4.9MPa⋅m1/2 and 17.2GPa, respectively.

An oxidation kinetics model of hot-pressed ZrB2-SiC composites was established and then proved by experiments. The relationship between oxidation rate and temperature was attained by reaction activation energy and frequency factor at the different oxidation stages. Results showed that the relations between the oxidation gain of unit area and the oxidation time are linear, conic and parabolic, respectively, during the stage of the oxidation prophase, midterm and anaphase.

Background: Adenosine deaminase (ADA) regulates purine metabolism through the conversion of adenosine to uric acid (UA). Adenosine and UA are closely associated with cardiovascular events, but the correlation between serum ADA activity and coronary artery disease (CAD) has not been defined.Methods: We performed a hospital-based retrospective case-control study that included a total of 5212 patients with CAD and 4717 sex- and age-matched controls. The serum activity of ADA was determined by peroxidase assays in an automatic biochemistry analyzer.Results: Serum ADA activity in the CAD group (10.08 ± 3.57 U/l) was significantly lower than that of the control group (11.71 ± 4.20 U/l, p< 0.001). After adjusting for conventional factors, serum ADA activity negatively correlated with the presence of CAD (odds ratio = 0.852, 95% confidence interval: 0.839–0.865, p< 0.001). Among the patients with CAD, serum ADA activity was lowest in patients with myocardial infarction (MI; 9.77 ± 3.80 U/l). Diabetes mellitus and hypertension increased the serum ADA activity in CAD patients.Conclusions: Serum ADA activity is significantly attenuated in patients with CAD, particularly in MI. We propose a mechanism by which the body maintains adenosine levels to protect the cardiovascular system in the event of CAD.

Multilayer graphene as a transparent interconnect electrode for the monolithic integration of GaN-based LEDs was investigated. On the basis of morphology determined by scanning electron microscopy and optoelectrical properties, it was found that graphene acts as an effective interconnect in GaN-based LED arrays. Graphene interconnect electrodes formed an air bridge between adjacent microchips, leading to the reduction in reverse leakage current. Compared with conventional LEDs with metal interconnects, the light output power of LEDs with graphene interconnects exhibited an improvement of 7.4%. This enhancement originated from the significantly reduced absorption of the light emitted from graphene electrodes, which was confirmed by spatial beam profile measurements.

GaN-based light emitting diodes (LEDs) with interconnecting indium tin oxide (ITO) nanowires were fabricated using self-assembled NaCl particles as etching masks. Compared to conventional LEDs with a planar ITO layer, it was found that the light output power (LOP) of the LEDs with a ITO layer with interconnecting nanowires was improved by 18.4% at an injection current of 20 mA. Meanwhile, a great improvement in the electrical characteristics of LEDs was also observed. These enhancements are attributed to the increase of photons escaping from the ITO surface with nanowires as well as the improved current spreading of the ITO layer with interconnecting ITO nanowires.