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Using CaO, Y2O3, Al2O3, and SiO2 micron-powders as raw materials, CaO–Y2O3–Al2O3–SiO2 (CYAS) glass was prepared using water cooling method. The coefficient of thermal expansion (CTE) of CYAS glass was found to be 4.3 × 10−6/K, which was similar to that of SiCf/SiC composites. The glass transition temperature of CYAS glass was determined to be 723.1 °C. With the increase of temperature, CYAS glass powder exhibited crystallization and sintering behaviors. Below 1300 °C, yttrium disilicate, mullite and cristobalite crystals gradually precipitated out. However, above 1300 °C, the crystals started diminishing, eventually disappearing after heat treatment at 1400 °C. CYAS glass powder was used to join SiCf/SiC composites. The results showed that the joint gradually densified as brazing temperature increased, while the phase in the interlayer was consistent with that of glass powder heated at the same temperature. The holding time had little effect on phase composition of the joint, while longer holding time was more beneficial to the elimination of residual bubbles in the interlayer and promoted the infiltration of glass solder into SiCf/SiC composites. The joint brazed at 1400 °C/30 min was dense and defect-free with the highest shear strength of about 57.1 MPa.

Ag/ZnO hybrid cages with well-preserved polyhedron shape and rich mesoporous structures were prepared thorough in situ pyrolysis of AgNO3 impregnated ZIF-8 precursor. Due to the bi-template function of ZIF-8, the as-prepared cages show well-defined hollow chamber inherited from the precursor and uniformly embedded Ag nanoparticles (NPs). The as-introduced Ag NPs could enhance the light absorption and promote charge separation, which finally improve the antibacterial performances. Therefore, compared with pure ZnO, the Ag/ZnO hybrid cages demonstrate prominent photocatalytic degradation of different organic dyes, such as Methylene Blue, Methylene Orange, Eosin and Rhodamine B under simulated sunlight. In addition, the hybrid Ag/ZnO cages exhibit outstanding inhibition performances against Escherichia coli, Staphylococcus aureus, and the highly infective Mycobacterium-tuberculosis. The photocatalytic and antibacterial mechanism of the hybrid Ag/ZnO cages were also studied in detail by means of optical/electrochemical dynamic tests and Ag+ and Zn2+ release measurements.

A combination method of precursor infiltration and pyrolysis (PIP), chemical vapor infiltration (CVI) and liquid silicon infiltration (LSI) was proposed to prepare PIP-SiC modified C/C–SiC brake materials. The SiC ceramic matrix pyrolyzed by polymethysilane (PMS) homogeneously dispersed in the fiber bundles region, which improved the plough resistance of local C/C region and the wear resistance of C/C–SiC brake materials. When the braking speed rises to 28 m/s, the fluctuation range of friction coefficient was limited to 0.026. The linear wear rate of the as-prepared composites was could be ~50% less than that of C/C–SiC, when the braking speed was above 15 m/s (for instance, the wear rate of 1.02 μm/(side·cycle) at 28 m/s less than 2.02 μm/(side·cycle) of traditional C/C– SiC). The fading ratio D of CoF under wet conditions was ~11%. The results showed that introducing PIP-SiC could stabilize the braking process and effectively prolong the service life of C/C–SiC brake materials.

Abandoned houses (AH) are focal points in urban communities by threatening local security, destroying housing markets, and burdening government finance in the U.S. legacy cities. In particular, individual-level AH detection provides essential information for fine-resolution urban studies, government decision-makers, and private sector practitioners. However, three primary conventional data sources (field data, utility data, and remote sensing data) cannot suffice to collect such fine-resolution data in the large spatial area via a cost-effective approach. To this end, Google Street View (GSV) imagery, which emerges as the mainstream open-access data source with global coverage, provides an opportunity to address this issue. Subsequently, a follow-up challenge confronting the detection of AH arises from the fact that it lacks an effective method that can discern authentic visual features from the redundant noise in GSV images. In this study, we aim to develop an effective method to detect individual-level AH from GSV imagery. Specifically, we developed a new hierarchical deep learning method to leverage both global and local visual features of AH in the detection. The method can be further divided into three steps: (1) Scene-based classification that can extract global visual features of AH was implemented through fine-tuning a pre-trained deep convolutional neural network (CNN) model. (2) We developed a patch-based classification method that can extract specific local features of AH. In this method, patches were generated from GSV images based on auto-detected local features, followed by being labeled as three categories: building patches, vegetation patches, and others. Two deep CNN models were employed to identify deteriorated building facade patches and overgrown vegetation patches, respectively. (3) Individual-level AH were detected by integrating scene classification results and patch classification results in a decision-tree model. Experimental results showed that the F-score of AH was 0.84 in a well-prepared dataset collected from five different Rust Belt cities. The proposed hierarchical deep learning approach effectively improved the accuracy comparing with the traditional scene-based method. In addition, the proposed method was applied to generate an AH map in a new site in Detroit, MI. Our study demonstrated the feasibility of GSV imagery in AH detection and showed great potential to detect AH in a large spatial extent.

The air flow and pollutant concentration fields in a street canyon affected by trees could affect the comfort and health of residents. At present, the description of the non-uniform/discontinuous distribution of leaves is difficult. In this study, the leaf distribution in the canopy was characterized by establishing non-continuous (uniform/random) algorithm based on a numerical simulation method, and the effects of canopy properties including, height, porosity and uniform/random leaf distribution, on the airflow and pollutant concentration fields in urban street canyons were investigated. The position of the tree canopy was found to directly affect the airflow field form and the air velocity distribution in the street canyon at low inflows. The average air velocity in the street canyon could be reduced significantly when the top of the tree canopy is near the top of the street canyon. The air velocity and pollutant concentration in the street canyon would vary only slightly due to the canopy porosity. Due to the increasing canopy porosity, the air velocity would increase, and the pollutant concentration would be reduced. The leaves are non-continuous and uniformly distributed at constant porosity, which does not significantly change the velocity distribution and pollutant concentration in the street canyon.

As the permanent submarine support structures for subsea wells, pipeline manifolds and pipeline terminations, the mudmat foundation works under obviously complex, nonlinear and uncertain loading, w...

In this study, a fully nonlinear method, in the time domain, is used to simulate ship motion caused by large waves, and the problem of wave climbing along the freeboard in large waves is studied. The method is based on a three-dimensional potential flow theory. Further, the nonlinear free surface condition is adopted, the incident potential and disturbance potential are separated from each other, and the problem of determining the disturbance potential is established. In order to consider the nonlinearity of the body surface, the wetted surface area of the hull is continuously updated with time and extended along the tangential direction of the uppermost grid when the free liquid level exceeds the height of the hull deck. In addition, an artificial damping layer is provided to eliminate the reflection of waves at the outflow boundary. Under the fully nonlinear boundary conditions, the perturbation potential is solved by the Rankine source boundary element method. Introducing auxiliary functions solves the coupling problem between motion and load in the process of solving rigid body motion equations. After the solution is completed, it is updated to the next time step using the Runge-Kutta 4th order method. In this study, the convergence of the computational grid of the numerical model is firstly verified. Then, the motion and load responses of a zero-speed ship in the regular wave of unit wave amplitude using this method are examined and compared with the linear method. The latter verifies the accuracy of this method in the linear field. Afterwards, in order to investigate the superiority of the fully nonlinear method when the nonlinear phenomenon is strong, the motion and load of the ship in the large amplitute wave are simulated and the influence of the nonlinear phenomenon is analyzed. Finally, the phenomenon of wave climbing generated in high waves is analyzed, and the relationship between wave and water heights is evaluated.

MAA (mesh aluminium alloy) is one of the most widely used explosion suppression materials in military and civilian applications. To systematically research the effect of MAA on the explosion reactions of flammable gases, we investigated the effect of MAA and AV (aluminium velvet) on the explosion of hydrogen-air, methane-air and acetylene-air mixtures. The results indicated that MAA and AV suppress the methane-air mixture explosion but significantly promote the explosions of the hydrogen-air mixture and the acetylene-air mixture. MAA and AV have the dual effect of promoting and suppressing an explosion. In addition, with an increase in filling density, the promotion of MAA and AV first strengthens and then weakens. The results of this study show that the properties of flammable gas, not the shapes of the explosion suppression materials, determine whether the dominant effect of explosion suppression material is promotion or suppression. Use of explosion suppression materials is not suitable for all flammable gases, especially highly reactive chemical fuels. Applying explosion suppression materials blindly may greatly increase safety risk.

Timely mapping of corn and soybean plays an important role in food security in the USA. A subpixel fraction derived from Land Remote-Sensing Satellite (System, Landsat) imagery during growing seaso...

Alteration mineralogy from shortwave infrared (SWIR) spectroscopy was compared with X-ray diffraction (XRD) analyses for samples from the Zhengguang intermediate sulfidation epithermal Au-Zn deposit, eastern Central Asian orogenic belt, northeast China. The SWIR and XRD analyses indicate that alteration minerals in the vein-adjacent halo mainly comprise quartz, illite, and locally pyrite (QIP) and chlorite, whereas samples from the pervasive propylitic alteration of host basaltic andesite lava contain epidote, chlorite, carbonate, montmorillonite, and locally illite. SWIR mineral identifications from automated mineral identification software may not always be accurate; thus, the results should be validated by the user. The wavelength position of the Al-OH (~2,200 nm; wAlOH) absorption feature can be used to approximate the composition of illite or white mica. However, caution is required when using the wAlOH value to assess paleotemperatures, as the composition of illite can be influenced by the composition of the host rocks or the hydrothermal fluid. In addition, values of the illite spectral maturity (ISM; ratio of the depth of the ~2,200 nm minima divided by the ~1,900 nm minima) can be affected by the presence of other hydrous minerals, quartz-sulfide veins, and absorption intensity (which can be a function of rock coloration). Despite these cautions, the spatial distribution and variation of the wAlOH and ISM values for illite suggest that the high paleotemperature hydrothermal upflow zones related to the Zhengguang Au-Zn deposit were located below ore zones I and IV, which are predicted to be proximal to the intrusive center of the system.

A series of experiments were conducted to investigate the wettability of graphite plate, graphite paper, NWCNTs Buckypaper, CVD-diamond by molten Ce and graphite plate by Cu–Ce binary alloy using a modified sessile drop method at 950 °C. The remarkable apparent equilibrium contact angles (graphite plate (0°)

Fluorine (F) in water has a negative effect on the environment and human health. Schwertmannite has potential remediation to contamination in solution. In this study, the adsorption mechanism and influencing factors of synthetic schwertmannite for low-concentration F were studied through batch experiments. The results suggested that the adsorption of F by schwertmannite reached equilibrium after about 60 min, and the adsorption efficiency exceeded 94%. The experimental data can be best-fit by the pseudo-second-order kinetic and Langmuir models well. Schwertmannite showed effective adsorption at pH 4, dosage 1.5 g L−1, low temperature, and low concentration of co-existing anion. The adsorption process was a spontaneous and exothermic reaction, which was dominated by chemical adsorption. FT-IR and XPS spectra analysis revealed that F adsorption on schwertmannite through the surface complexation and anion exchange reaction between SO42− and OH− with F−, especially the primary role of OH−. The results can provide theoretical support for the schwertmannite application in the treatment of F-containing wastewater.

Prunus triloba var. plena, also known as flowering plum, is a perennial deciduous shrub admired for its brilliant pink-purple blooms. Chloroplast (cp) DNA is highly conserved in structure and gene arrangement, making cp genomic data valuable resources for species delimitation and phylogenetics. The cp genome of P. triloba var. plena was de novo assembled with the aim of developing cp-derived molecular markers and deepening the understanding of phylogenetic relationship among Prunus species. The complete cp genome was 158,022 bp in length, with a GC content of 36.8%. The plastome featured a typical quadripartite structure, consisting of a pair of inverted repeat (IR) regions of 26,379 bp, separated by a large single copy (LSC) region of 86,242 bp, and a small single copy (SSC) region of 19,022 bp. The cp genome encoded 134 genes, including 87 protein-coding genes, 39 tRNA genes, and 8 rRNA genes. A total of 59 simple sequence repeat (SSR) were identified, 68% of which were located in the intergenic regions. An obvious A/T bias was observed in the majority of SSRs detected. Besides, 48 repeats in different sizes and types were detected. These repeats, together with SSRs and the divergence hotspots detected, could serve as markers facilitating species discrimination and evolutionary research in Prunus. Using plastome sequences, we re-investigated the phylogenetic relationship among 32 Prunus species. These species explicitly clustered into three monophyletic clades, among which P. triloba var. plena was closely related to species in the subgenera Amygdalus and Prunus.

Yellow-emitting YAG:Ce transparent ceramic is recognized as an ideal color converter in high-power blue LEDs and LDs, but the absence of scattering centers in its microstructure leads to a low light extraction efficiency and poor light uniformity. Here, taking advantage of the scattering effect and the transparency of YAG:Ce ceramics, Ce-free YAG phase was used as a second component to form a composite with YAG:Ce phosphor. The sintered YAG:Ce-YAG ceramic possessed a high transparency of ∼63 % and a thermal conductivity of 8.9 Wm−1 K−1. Due to its beneficial thermal properties and high external quantum efficiency of 70.2 %, the YAG:Ce-YAG ceramic could be excited under a high blue-laser flux density of up to 9.60 W/mm2 and showed a luminous emittance of 1220 lm/mm2. Due to light scattering arising from the slightly different refractive indices of the two phases, the designed YAG:Ce-YAG ceramic showed better lighting effects than a single-phase transparent YAG:Ce ceramic.

Ribes odoratum, commonly known as clove currant, is a perennial deciduous shrub noted for its long-lasting fragrant flowers and edible fruits. Owing to its ornamental values, this species has been widely used in city gardening and urban landscaping. Here, the complete cp genome of R. odoratum was de novo assembled for the first time. The plastome is 157,152 bp in length, with a GC content of 38.2%. The cp genome featured a typical quadripartite structure, consisting of a pair of inverted repeat regions of 25,961 bp, separated by a large single copy region of 86,896 bp, and a small single copy region of 18,333 bp. A total of 131 genes were annotated in the plastome, including 86 protein coding genes, 37 tRNA genes, and 8 rRNA genes. 56 SSRs were identified, among which, 82.35% were located in the intergenic regions. A strong A/T bias in base composition was observed in these cpSSRs. In addition, 49 repeats of different sizes and types were also found in the plastome. Through comparison, seven divergence hotspots were identified between the cp genomes of R. odoratum and R. fasciculatum var. chinense. Sequences of these divergent regions could be developed as potential markers for species delimitation in further studies. We re-investigated the relationship aomong 32 Saxifragales species through plastome-based phylogenywhich revealed that R. odoratum as a sister of R. fasciculatum var. chinense. Thus, our study provides genomic resources and valuable reference for marker development and phylogenomics in Ribes.

Carbon dots (CDs), possessing unexpected advantages of photostability, biocompatibility and low toxicity, are regarded as novel nanomaterials in fluorescence (FL) imaging. Doping Gd element in CDs makes them have the ability to be used for magnetic resonance (MR) and FL imaging simultaneously. However, CDs reported before exhibit obvious defects like low photoluminescence (PL) quantum yield (QY) or biotoxicity. In this work, we use gadolinium meglumine, a material with relatively low biotoxicity, along with citric acid and diethylenetriamine to synthesize Gd-doped CDs (Gd-CDs) by a one-step hydrothermal method. The prepared Gd-CDs exhibit excitation-independent emission with a PL QY of 78.05% and a longitudinal relaxivity of 7.37 mM-1 S-1, which endows the composite with high-performance in MR/FL imaging. Meanwhile, the FL intensity of Gd-CDs remains stable in the presence of multiple amino acids, which indicates that the FL imaging effect should not be impacted significantly in microenvironments in vivo. In addition to the inconspicuous cytotoxicity, Gd-CDs could be used efficiently for dual-modal molecular imaging to detect diseases such as tumors in the early stages.

Copper oxide has aroused great concern in energy storage fields due to its properties of high theoretical capacitance, low cost and mild toxicity. However, its wide application still remains challenges owing to its poor electrical conductivity and unstable cycling life. Binder-free foam electrodes possess abundant porous structures and high specific surface area, which could get good contact with electrolyte. Herein, we demonstrate Ag nanoparticles decorated CuxO nanowires grown spontaneously on copper foam (CF) electrode for asymmetric supercapacitor. The skeleton structure of CF provides large amounts of active sites for the growth of CuxO nanowires. Moreover, Ag nanoparticles further decrease the internal resistance and enhance the electrochemical performance. Ag/CuxO/CF-40 electrode presents a high area specific capacitance of 1192 mF cm−2 at 2 mA cm−2 and the influence of surface capacitance-dominated process and diffusion-controlled process are discussed in detail. Besides, the energy density of the as-prepared asymmetric supercapacitor (ASC) reaches 46.32 μWh cm−2 at a power density of 3.00 mW cm−2. A 2V LED is lighted successfully by two ASC in series. This work provides a new strategy to prepare low internal resistance and binder-free flexible Ag/CuxO/CF electrode, which demonstrates a good potential application in flexible supercapacitors or other wearable electronic devices.

Fingerprints form when fingers touch a solid surfaceand are considered the best way for individual identification. However, the current latent fingerprint (LFP) developing methods cannot meet the demand for high sensitivity and being convenient and healthy. Herein, bifunctional Fe3O4@SiO2-CsPbBr3 powders have been designed and fabricated and exhibit good magnetic and strong fluorescent properties. The magnetism of Fe3O4 can avoid dust flying, while the fluorescence of CsPbBr3 ensures the high definition of LFPs. Clear fingerprints have been detected on various solid substrates using the Fe3O4@SiO2-CsPbBr3 powders instead of eikonogen. Detailed characterization studies suggest that the ammonium cationic groups on the surface of nanoparticles (NPs) have strong adhesive interactions with the residues of fingerprints because of the electrostatic attraction between them. Therefore, the convenient operation and excellent resolution offer great opportunity in the practical application of fingerprint detection and other areas.

Summary To simulate the drying process of cut tobacco in a batch rotary dryer, six different models of equilibrium moisture content were selected to calculate the driving force of mass transfer, and a mathematical model of heat and mass transfer was numerically solved. The multi-objective nonlinear problem of heat and mass transfer coefficients was optimized by employing a weight factor. The simulation results showed that the weight factor r was an important parameter for fitting results of moisture content and temperature. The model evaluation indices almost reached their minimal values with r at 0.1. For all the six equilibrium/classic models the fit was better for moisture content than for temperature. One model (M-Hen/C) was superior to other equilibrium/classic models and the REA (reaction engineering approach) model. This study aims for an understanding of heat and mass transfer in the tobacco drying process, and provides a theoretical framework to support the prediction of temperature and moisture in various drying situations.

In this study, Y2O3–Al2O3–SiO2 (YAS) glass was prepared from Y2O3, Al2O3, and SiO2 micron powders. Thermal expansion coefficient of as-obtained YAS glass was about 3.9 × 10−6, matching-well with that of SiCf/SiC composites. SiCf/SiC composites were then brazed under pressure-less state by YAS glass and effects of brazing temperature on microstructures and properties of resulting joints were investigated. The results showed that glass powder in brazed seam sintered and precipitated yttrium disilicate, cristobalite, and mullite crystals after heat treatment. With the increase in temperature, joint layer gradually densified and got tightly bonded to SiCf/SiC composite. The optimal brazing parameter was recorded as 1400 °C/30 min and shear strength of the joint was 51.7 MPa. Formation mechanism of glass-ceramic joints was proposed based on combined analysis of microstructure and fracture morphology of joints brazed at different temperatures. Thermal shock resistance testing of joints was also carried out, which depicted decline in shear strength with the increase of thermal shock times. The strength of the joint after three successive thermal shock cycles at 1200 °C was 35.6 MPa, equivalent to 69% of that without thermal shock.

Low-dimensional metal halide hybrids (OIMHs) have recently been explored as single-component white-light emitters for use in solid-state lighting. However, it still remains challenging to realize tunable white-light emission in lead-free zero-dimensional (0D) hybrid system. Here, a combination strategy has been proposed through doping Sb3+ enabling and balancing multiple emission centers toward the multiband warm white light. We first synthesized a new lead-free 0D (C8NH12)6InBr9·H2O single crystal, in which isolated [InBr6]3- octahedral units are separated by large organic cations [C8NH12]+. (C8NH12)6InBr9·H2O exhibits dual-band emissions with one intense cyan emission and a weak red emission tail. The low-energy ultrabroadband red emission tail can be greatly enhanced by the Sb3+ doping. Experimental data and first-principles calculations reveal that the original dominant cyan emission is originated from the organic cations [C8NH12]+ and that the broadband red emission is ascribed to self-trapped excitons in [In(Sb)Br6]3-. When the Sb concentration is 0.1%, a single-component warm white-light emission with a photoluminescence quantum efficiency of 23.36%, correlated color temperature of 3347 K, and a color rendering index up to 84 can be achieved. This work represents a significant step toward the realization of single-component white-light emissions in environmental-friendly, high-performance 0D metal halide light-emitting materials.

Multidrug-resistant (MDR) bacteria-induced infections are becoming challenging issues threatening human health and life. Current antibiotics can hardly tackle this problem. Herein, we present a strategy to prepare mercaptophenylboronic acid (MBA)-activated gold nanoparticles (Au NPs) as an antibacterial agent against MDR bacteria. Both Au NPs and MBA cannot serve as antibiotics. However, when MBA attaches on Au NPs, the Au_MBA NPs show potent antibacterial activities against Gram-positive MDR clinical isolates (e.g., MDR Staphyloccocus aureus, MDR S. aureus; MDR Staphyloccocus epidermidis, MDR S. epidermidis). Furthermore, Au_MBA NPs show an extremely high median lethal dose (LD50,i.v., 960 mg/kg), which is much higher than those of most of the clinically used antibiotics. As an application example, we dope Au_MBA NPs with electrospun poly(e-caprolactone) (PCL)/gelatin nanofibrous membranes as wound dressings, which show striking ability to remedy S. aureus- or MDR S. aureus-infected full-thickness skin wounds on rats. Our study provides a novel strategy for treating MDR bacteria-infected wounds in a simple, low-cost, and efficient way, which holds promise for broad clinical applications.

Epitaxial Fe3O4 thin films grown on single crystal MgO(001) present well-defined model systems to study fundamental multivalent ion diffusion and associated phase transition processes in transition...

Isolation and screening of microalgal species from natural habitats should be a continues work to discover effective species for biofuel generation and wastewater treatment. In the current study, microalgal species namely Tetradesmus dimorphus GEEL-04 and Desmodesmus asymmetricus GEEL-05 were isolated, identified, and assessed for growth kinetics, nutrients removal efficiency, and whole biomass composition. T. dimorphus showed higher growth (1.46 OD680nm) compared with D. asymmetricus (1.16 OD680nm), and both showed 99% total nitrogen and total phosphorous removal. T. dimorphus and D. asymmetricus accumulated higher protein content (40.02 and 45.10%), carbohydrate (31.91 and 24.64%), and lipid (15.41 and 24.16%), respectively. The FTIR spectra absorbance revealed different function groups in microalgal biomass available for biofuel generation. Elemental analysis of microalgal biomass showed high carbon content 50.13% and 43.01% for T. dimorphus and D. asymmetricus, respectively. Thermogravimetric analysis indicated ≥ 80% volatile content in both isolates. The fatty acid composition of both microalgal strains showed high palmitic acid and linoleic acid corresponding to high quality biodiesel. These results indicated that the T. dimorphus and D. asymmetricus could be potential candidates for high biocomponents accumulation and N, P removal.

Ti3SiC2, as ternary layered ceramic with good electrical and thermal conductivity, has great application potential in the field of absorbing materials. Absorbing materials are also increasingly required to be lightweight, ultrathin, and flexible. Herein, Ti3SiC2/poly (TEP, DOP and PVB) composite film was biomimetically designed and fabricated by type casting process. As-fabricated composite film with 38% content of Ti3SiC2 was only 1.62 mm in thickness but exhibited excellent absorbing performance. The maximum reflection loss value of Ti3SiC2-based films was as high as −38.41dB and absorption bandwidth below −10 dB was 2.480 GHz. Polymer matrix wrapped around Ti3SiC2 not only enhanced the flexibility of the film, but also regulated its impedance matching and complex dielectric constant compared with pure Ti3SiC2. Superior wave absorption and flexibility imply excellent potential of this Ti3SiC2-based composite film for eliminating electromagnetic interference.

The design of metal-organic frameworks (MOFs) that incorporate more than one metal cluster constituent is a challenging task. Conventional one-pot reaction protocols require judicious selection of ligand and metal ion precursors, yet remain unpredictable. Stable, preformed nanoclusters, with ligand shells that can undergo additional coordination-driven reactions, provide a platform for assembling multi-cluster solids with precision. Herein, a discrete Co6 S8 (PTA)6 (PTA=1,3,5-triaza-7-phosphaadamantane) superatomic-metalloligand is assembled into a three-dimensional (3D) coordination polymer comprising Cu4 I4 secondary building units (SBUs). The resulting heterobimetallic framework (1) contains two distinct cluster constituents and bifunctional PTA linkers. Solid-state diffuse reflectance studies reveal that 1 is an optical semiconductor with a band-gap of 1.59 eV. Framework-modified electrodes exhibit reversible redox behavior in the solid state arising from the Co6 S8 superatoms, which remain intact during framework synthesis.

Ti3C2TX MXenes have great application prospects in the electromagnetic shielding field owing to their unique accordion structure and excellent electrical conductivity. However, understanding the correlation between their thermal stability and electromagnetic shielding performance is still lacking. Additionally, owing to the complex etching environment, some termination groups are present on the surface of MXenes, significantly affecting their thermal and electromagnetic performance. Here, to solve these problems, a heat treatment process was used. In this study, the effect of heat treatment on the removal of these surface adsorption groups was evaluated. Moreover, the evolution of structure, phase, and electromagnetic shielding properties of MXenes with the change in heat treatment temperature was also studied in detail. After heat treatment at 1100 °C, the phase of MXenes changed. Multilayer-TiC, a derivative of MXenes, still exhibited excellent shielding performance, which can be attributed to the elimination of surface end groups, the maintenance of multiple structure, and the increase in content about amorphous C. The total and absorbing shielding effectiveness reached 76.1 dB and 61.3 dB, respectively. Its conductivity was 265 S/m. This study is valuable in studying application prospects of Ti3C2TX MXene in high temperature fields, such as the field of electromagnetic shielding.

To get a quick and accurate hail damage simulation method for cotton, two-year experiments about two different simulation methods were conducted at the initial bloom stage in 2017 and 2018, respectively. Method one: five defoliation treatments (0%, 25%, 50%, 75%, and 100%) were conducted in 2017; method two: canopy height was decreased by 0%, 30%, 60%, and 90% by self-made tools in 2018. Field design was a randomized complete block with three replications. Canopy coverage (CC), leaf area index (LAI), leaf dry weight (LDW), leaf mass per unit area (LMA) and yield were obtained after damage. Results showed that LAI, LDW, CC, LMA and yield decreased with the increasing damage level in two simulations, yield decreased significantly when damage level was severe. Comparing two simulated hail damages with natural hail damage, it was shown that with the increasing damage level, the variations of LDW, CC, and yield (take LAI as an independent variable) for method two were closer to natural hail damage than those for method one. These results indicate that method two is more appropriate than method one for simulation of hail damage to cotton, which could be helpful for farmers and insurance companies to estimate potential economic losses.

This article provides a framework for estimating intergenerational mobility elasticities (IGEs) of children’s income with respect to parental income. We allow the IGEs to be heterogeneous, by leavi...

We report, herein, the synthesis of thieno[3,2-b]pyrroles from the direct oxidative [4 + 1] cyclization of 2-alkynyl pyrrolidines with elemental sulfur. This transformation likely originates from e...

Pretreatment to enhance the enzymatic digestibility of cellulose usually alters the structure of lignin, resulting in subsequent inferior depolymerization and utilization. Herein, a physicochemical pretreatment strategy, specifically, using a recyclable acid hydrotrope (p-toluenesulfonic acid, p-TsOH) followed by 10 s of ultrasonic treatment, was developed to facilitate high-value lignin extraction from lignocellulosic biomass and improve enzymatic hydrolysis for high-titer ethanol production. The wood material (poplar) was first treated with the recyclable p-TsOH aqueous solution under mild conditions (C80T80t15) to extract the lignin. The obtained lignin exhibited excellent properties, including a high hydroxyl (OH) content (4.19 and 4.07 mmol/g of aliphatic and phenolic OH, respectively), abundant β-O-4 aryl ether linkages (60%), a low Mw (3357 ± 121 g/mol), and a narrow polydispersity (2.28, Mw/Mn), according to the results from FTIR spectroscopy, TGA, 31P NMR spectroscopy, 2D-HSQC NMR spectroscopy, and GPC. The pretreated substrates were then subjected to 10 s of ultrasonication to improve the enzymatic saccharification and finally afford ethanol by quasi-simultaneous enzymatic saccharification and fermentation (Q-SSF). The highest ethanol concentration (40.08 ± 3 g/L) was obtained after 60 h of fermentation, and the residual glucose concentration was only 4.22 ± 1 g/L; this experimental ethanol yield was equivalent to the theoretical ethanol yield of 81.87 ± 4% based on the glucan content. In short, this pretreatment method simultaneously enhanced the accessibility of cellulose to enzymatic hydrolysis and provided high-value lignin.

In this paper, a visible-light-promoted cross-coupling of 4-alkyl-1,4-dihydropyridines with thio-/selenium sulfonates under transition-metal-free conditions is described. This strategy features easily available substrates, mild reaction conditions, high yields, and high chemoselectivity. A novel synthetic route for the construction of a sulfide or selenide C

Determining the role of lattice oxygen in the oxygen evolution reaction (OER) is pivotal to understanding reaction mechanisms and predictive design of electrocatalysts based on transition metal oxi...

An efficient and benign iron-catalyzed room-temperature method was developed for direct sequential C(sp3)–H/N–H annulation to construct pyrroloindole scaffolds. This strategy features cheap and rea...

The nonlocality research of quantum entanglement plays an important role in the development of quantum mechanics theory and quantum information technology. As multipartite entangled state is a rare quantum resource, its nonlocality research has always been an important subject in the study of quantum theory. In this paper, we focus on N entangled states composed of N copies of an entangled state. First, a new Bell test with respect to N entangled states is presented, and lifting Bell inequalities are applied to certify nonlocality. Second, we obtain the nonlocality certification standard of N entangled states by parity binning lifting Bell inequality. Third, we prove the conjecture that N + 2 entangled states must be local if N entangled states are local certified by parity binning lifting Bell inequality. The research will promote the theoretical research progress of quantum coherence, and provide theoretical basis and technical support for the multipartite entangled states application in quantum cryptographic protocols.

Spot blotch, caused by fungal pathogen Bipolaris sorokiniana Shoemaker, is one of the most frequent diseases affecting barley-growing regions worldwide. In this study, we reported the genome sequence of the highly virulent B. sorokiniana strain GN1 using the Illumina HiSeq 4000 platform. In total, 57 million 150-nucleotide paired-end clean reads were obtained and assembled into 96 scaffolds with an estimated genome size of 34.33 Mb. Furthermore, we identified genes that may be associated with strain-specific virulence and performed phylogenetic analysis of GN1 with five other Bipolaris spp. These results for GN1 will provide important information in understanding its molecular underpinning of pathogenicity and help identify novel sources of genetic resistance for improving disease resistance in barley.

In this paper, we propose a multiple-input single-output ghost imaging scheme, named MISO-GI. In the scheme, K spatiotemporal speckle pattern sources ( multiple input ) simultaneously generate K different spatiotemporal modulated speckle patterns which then are illuminated on an unknown object at the same time. Then, a non-spatial-resolution bucket detector ( single output ) is used to detect the light field interacting with the object. According to the orthogonality of speckle patterns from different spatiotemporal speckle pattern sources, the detection signal is separated into K components corresponding to K spatiotemporal modulated speckle patterns. With the effective recovery algorithm, an image is reconstructed by using all spatiotemporal modulated speckle patterns and their corresponding components of detection signals. Both experimental and simulation results verify the feasibility of the proposed MISO-GI scheme. Moreover, the results also show that the proposed MISO-GI scheme could reduce the total sampling time by K times and improve the imaging quality comparing to traditional GI, without the decrease of the number of speckle patterns and the picture time as well as the consumption of other light field dimensions. It provides a promising avenue to realize GI with limited sampling time and has potential for more applications.

The high surface energy of nanomaterials endows them a metastable nature, which greatly limits their application. However, in some cases, the degradation process derived from the poor stability of nanomaterials offers an unconventional approach to design and obtain functional nanomaterials. Herein, based on the poor stability of ZnSe-[DETA]0.5 hybrid nanobelts, we developed a new strategy to chemically graphitize and functionalize graphene oxide (GO). When ZnSe[DETA]0.5 hybrid nanobelts encountered a strong acid, they were attacked by H+ cations and could release highly reactive Se2− anions into the reaction solution. Like other common reductants (such as N2H4·H2O), these Se2− anions exhibited an excellent ability to restore the structure of GO. The structural restoration of GO was greatly affected by the reaction time, the volume of HCl, and the mass ratio between GO and ZnSe[DETA]0.5 nanobelts. By carefully controlling the reaction process and the post-processing process, we finally obtained several Se-based reduced GO (RGO) nanocomposites (such as ZnSe/Se-RGO, ZnSe-RGO, and Se-RGO) and various selenide/metal-RGO nanocomposites (such as Ag2Se-RGO, Cu2Se-RGO, and Pt-RGO). Although the original structure and composition of ZnSe[DETA]0.5 nanobelts are destroyed, the procedure presents an unconventional way to chemically graphitize and functionalize GO and thus provides a new material synthesis platform for nanocomposites.

This study was designed to isolate microalgal species which can tolerate severe environmental stresses and can be used for wastewater treatment and biofuel generation. Three different microalgal strains (including Chlorella sorokiniana GEEL-01, Parachlorella kessleri GEEL-02, and Parachlorella kessleri GEEL-03) were isolated from a wastewater treatment plant and Waterwheel Park. The highest growth rate (1.61 OD680nm) was observed for C. sorokiniana GEEL-01 with highest removal of total nitrogen (1.5 mg L−1 day−1) and total phosphorus (1.82 mg L−1 day−1). The biocomponents of the isolated species ranged from 19.47–29.64%, 39.39–52.51%, and 15.08–22.75% for carbohydrate, protein, and lipid, respectively, based on the dry cell weight (DCW). The function groups in microalgal biocompounds were also confirmed by Fourier-transform infrared radiation (FT-IR) spectra, indicated their ability for biofuel generation. Ultimate and proximate analyses of C. sorokiniana GEEL-01 showed high carbon (54.24% DCW) and volatile content (92.69% DCW), compare to other strains. Moreover, it exhibited a significant accumulation of lipid with an increase in the fractions of saturated fatty acids (64.5%), and the major fatty acids were palmitic acid (11.17%), stearic acid (33.86%), oleic acid (9.84%), and linoleic acid (11.56%). Biodiesel derived from the major fatty acids had optimum engine efficiency properties including iodine value (77.34 g I2/100 g oil) and cetane number (54.83). Cultivation of C. sorokiniana GEEL-01 can serve as a dual function of biodiesel feedstock generation and nutrients removal.

Hematite (Fe2O3) is a well-known oxide semiconductor suitable for photoelectrochemical (PEC) water splitting and industry gas sensing. It is widely known that Sn doping of Fe2O3 can enhance the device performance, yet the underlying mechanism remains elusive. In this work, we determine the relationship between electronic structure, optical properties, and PEC activity of Sn-doped Fe2O3 by studying highly crystalline, well-controlled thin films prepared by pulsed laser deposition (PLD). We show that Sn doping substantially increases the n-type conductivity of Fe2O3, and the conduction mechanism is better described by a small-polaron hopping (SPH) model. Only 0.2% Sn doping significantly reduces the activation energy barrier for SPH conduction from at least 0.5 eV for undoped Fe2O3 to 0.14 eV for doped ones. A combination of X-ray photoemission, X-ray absorption spectroscopy, and DFT calculations reveals that the Fermi level gradually shifts toward the conduction band minimum with Sn doping. A localized Fe2+-like gap state is observed at the top of the valence band, accounting for the SPH conduction. Interestingly, different from the literature, only 0.2% Sn doping in Fe2O3 significantly improves the PEC activity, while more Sn decreases it. The improved PEC activity is partially attributed to an increased band bending potential which facilitates the charge separation at the space charge region. The reduced activation energy barrier for SPH will facilitate the transport of photoexcited carriers for the enhanced PEC, which is of interest for further carrier dynamics study.

Vacancy-ordered double perovskites, having a great application in optoelectronic and thermoelectric devices, are variants of metal-halide perovskites. The PBE and HSE06 functionals for the first-pr...

The BET family of proteins consists of BRD2, BRD3, BRD4, and BRDt. Each protein contains two distinct bromodomains (BD1 and BD2). BET family bromodomain inhibitors under clinical development for on...

Volatile components in fresh leaves are involved in the regulation of many stress responses, such as insect damage, fungal infection and high temperature. However, the potential function of volatile components in hyperosmotic response is largely unknown. Here, we found that 7-day hyperosmotic treatment specifically led to the accumulation of (Z)-3-hexen-1-ol, (E)-2-hexenal and methyl salicylate. Transcriptome and qRT-PCR analyses suggested the activation of linolenic acid degradation and methyl salicylate processes. Importantly, exogenous (Z)-3-hexen-1-ol pretreatment dramatically enhanced the hyperosmotic stress tolerance of tea plants and decreased stomatal conductance, whereas (E)-2-hexenal and methyl salicylate pretreatments did not exhibit such a function. qRT-PCR analysis revealed that exogenous ABA induced the expressions of related enzyme genes, and (Z)-3-hexen-1-ol could up-regulate the expressions of many DREB and RD genes. Moreover, exogenous (Z)-3-hexen-1-ol tremendously induced the expressions of specific LOX and ADH genes within 24 h. Taken together, hyperosmotic stress induced (Z)-3-hexen-1-ol accumulation in tea plant via the activation of most LOX, HPL and ADH genes, while (Z)-3-hexen-1-ol could dramatically enhance the hyperosmotic stress tolerance via the decrease of stomatal conductance and MDA, accumulation of ABA and proline, activation of DREB and RD gene expressions, and probably positive feedback regulation of LOXs and ADHs. KEY MESSAGE: Hyperosmotic stress induced (Z)-3-hexen-1-ol accumulation in Camellia sinensis via the up-regulation of most LOX, HPL and ADH genes, while (Z)-3-hexen-1-ol could dramatically enhance the hyperosmotic stress tolerance via the decrease of stomatal conductance, accumulation of proline, activation of DREB and RD gene expressions, and probably positive feedback regulation of LOXs and ADHs.

Previous reports have shown that, when Verticillium dahliae localizes at the root surface, many microRNAs (miRNAs) were identified at the early induction stage. Here, we constructed two groups from two timepoints of small RNA (sRNA) in cotton root responses to V. dahliae at the later induction stage, pathogen localizing in the interior of root tissue. We identified 71 known and 378 novel miRNAs from six libraries of the pathogen-induced and the control sRNAs. Combined with degradome and sRNA sequencing, 178 corresponding miRNA target genes were identified, in which 40 target genes from differentially expressed miRNAs were primarily associated with oxidation-reduction and stress responses. More importantly, we characterized the cotton miR477-CBP60A module in the later response of the plant to V. dahliae infection. A β-glucuronidase fusion reporter and cleavage site analysis showed that ghr-miR477 directly cleaved the messenger RNA of GhCBP60A in the posttranscriptional process. The ghr-miR477-silencing decreased plant resistance to this fungus, while the knockdown of GhCBP60A increased plant resistance, which regulated GhICS1 expression to determine salicylic acid level. Our data documented that numerous later-inducible miRNAs in the plant response to V. dahliae, suggesting that these miRNAs play important roles in plant resistance to vascular disease.

Herein we describe the discovery of A-1331852, a first-in-class orally active BCL-XL inhibitor that selectively and potently induces apoptosis in BCL-XL-dependent tumor cells. This molecule was generated by re-engineering our previously reported BCL-XL inhibitor A-1155463 using structure-based drug design. Key design elements included rigidification of the A-1155463 pharmacophore and introduction of sp3-rich moieties capable of generating highly productive interactions within the key P4 pocket of BCL-XL. A-1331852 has since been used as a critical tool molecule for further exploring BCL-2 family protein biology, while also representing an attractive entry into a drug discovery program.

We introgressed wheatgrass germplasm from the octoploid amphiploid Triticum aestivum× Lophopyrum elongatum into wheat by manipulating the wheat Ph1 gene and discovered and characterized 130 introgression lines harboring single or, in various combinations, complete and recombined L. elongatum chromosomes. Diploid wheatgrass Lophopyrum elongatum (genomes EE) possesses valuable traits for wheat genetics and breeding. We evaluated several strategies for introgression of this germplasm into wheat. To detect it, we developed and validated multiplexed sets of Sequenom MassARRAY single nucleotide polymorphism (SNP) markers, which differentiated disomic and monosomic L. elongatum chromosomes from wheat chromosomes. We identified 130 introgression lines (ILs), which harbored 108 complete and 89 recombined L. elongatum chromosomes. Of the latter, 59 chromosomes were recombined by one or more crossovers and 30 were involved in centromeric (Robertsonian) translocations or were telocentric. To identify wheat chromosomes substituted for or recombined with L. elongatum chromosomes, we genotyped the ILs with the wheat 90-K Infinium SNP array. We found that most of the wheat 90-K probes correctly detected their targets in the L. elongatum genome and showed that some wheat SNPs are ancient and had originated prior to the divergence of the wheat and L. elongatum lineages. Of the 130 ILs, 52% were homozygous for Ph1 deletion and thus are staged to be recombined further. We failed to detect in the L. elongatum genome the 4/5 reciprocal translocation that has been reported in Thinopyrum bessarabicum and several other Triticeae genomes.

As a new generation advanced display or projection technology, laser displays or projectors have attracted great attention owing to their ultra-high brightness, energy saving nature, brilliant image quality and/or large sizes. However, for laser displays or projectors without using three primary laser diodes, the lack of appropriate blue-laser-driven color converters is a big limitation and challenge. In this work, we propose to develop laminated phosphor-in-glass (PiG) films as laser-driven color converters for wide-color-gamut and high-brightness laser displays. The β-Sialon:Eu and CaAlSiN3-LiSi2N2-Si2N2O, Calson:Ce phosphors were chosen as the green and orange emitters, respectively, and were co-fired with glass frits on a sapphire substrate to form PiG films. No interfacial reactions between phosphors and glass were identified, and phosphor powders were uniformly distributed in the glass matrix. The phosphor content and the film thickness had an influence on the microstructure, luminance saturation and optical properties of the PiG films under laser light irradiation; both PiG films reached a maximum luminance saturation of 6.09 W mm−2 when their microstructures were optimized. The lamination architecture of the PiG films had a great impact on the optical properties of the laser-driven white light, and the maximum ones were achieved as the green-emitting PiG film was positioned on the orange-emitting film adhered to the sapphire substrate. Under 4.82 W mm−2 blue laser excitation, the laminated double-layer PiG films enabled the creation of white light with a wide color gamut of 107% NTSC, luminous efficacy of 74.44 lm W−1, luminous flux of 282.13 lm and color temperature of 7902 K. These results indicate that the laminated PiG films are promising color converters for use in high-power and wide-color-gamut laser displays or projectors.

Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific. It has high ecological and economic value as a biomarker of water quality and as a high-quality feed in aquaculture and fisheries and is considered a delicacy in some areas of Asia. However, it has experienced a marked reduction in recent years due to overexploitation as well as changes in the environment and climate. Here, to comprehensively understand its genetic background and thus provide insights for better conservation and utilization of this species, we assessed the genetic variability and demographic history of T. heterochaetus individuals sampled from eight locations along the coasts of southeast China and north Vietnam based on mitochondrial cytochrome c oxidase I ( COI) sequences. We observed high haplotype diversity ( Hd), with an average of 0.926, but relatively low nucleotide diversity ( π), with a mean of 0.032 across all samples. A total of 94 polymorphic sites and 85 haplotypes were identified among 320 individuals. The pairwise genetic distances among haplotypes ranged from 0.001 to 0.067, with the high intraspecific divergence possibly reflecting geographic isolation and gene pool fragmentation. Significant genetic structures were revealed among the studied locations; specifically, the eight locations could be treated as six genetically different populations based on pairwise Φ ST results (0.026-0.951, P

Night-Time light imagery has become a very popular data source for monitoring the intensity of human activity in urban environments. Subpixel information is required in many applications, however, ...

Microalgae have been reported in many studies with high biomass, high carbohydrate content, fast growth rate and multiple bio-activities, while Dictyosphaerium sp. was rarely studied. Polysaccharide prove to be remarkable in many biological activities. To optimize the effects of the ultrasonic-assisted extraction parameters on the yield of polysaccharide from Dictyosphaerium sp., a single-factor experiment and response surface methodology (RSM) with a central composite rotatable design were employed. Four independent variables were investigated: X1 (ratio of raw microalgal powder to water), X2 (extraction temperature), X3 (extraction time), X4 (extraction power). The optimal conditions obtained via single-factor experiment were: X1 (1:25), X2 (50 °C), X3 (50 min), X4 (500 W), while according to the analysis of RSM, the optimum conditions were: X1 (1:26), X2 (58 °C), X3 (55 min), X4 (525 W). The refined polysaccharide were further prepared and characterized using SEM, FT-IR, XRD and TGA/DSC. Five kinds of antioxidant assays were carried out and the results indicated that the refined polysaccharide had strong scavenging ability to DPPH· and OH·. This study provides theoretical and experimental basis for the development and utilization of microalgal resources.