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• Al 2 O 3 /ZrB 2 thin films exhibit a favorable thermal stability at 600 °C for 30 h. • Al 2 O 3 /ZrB 2 thin films exhibit a high average infrared reflectance of 0.86 after annealing at 750 °C for 2 h. • Al 2 O 3 thin film can effectively prevent diffusion of oxygen atoms during the heat treatment process. In the present research, ZrB 2 thin films and Al 2 O 3 /ZrB 2 multilayer were deposited on silicon substrates using magnetron sputtering method. To investigate the thermal stability of the thin films, films were annealed at temperatures of 600 °C, 700 °C and 800 °C, respectively. Results from X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectrometer (FTIR) suggested that ZrB 2 thin films were severely oxidized at 700 °C for 2 h which caused the obvious increase of infrared emissivity. In contrast, double-layer-structure Al 2 O 3 /ZrB 2 thin films exhibited a low infrared emissivity of 0.16 after annealing at 750 °C for 2 h. Similarity, ZrB 2 thin films showed a rise of infrared emissivity after annealing at 600 °C for 10 h. However, double-layer-structure Al 2 O 3 /ZrB 2 thin films exhibited a favorable thermal stability at 600 °C for 30 h with a low average infrared emissivity of 0.13 in the waveband of 2–14 μm. Compared with ZrB 2 thin films, double-layer-structure Al 2 O 3 /ZrB 2 thin films could work as low infrared emissivity layers at higher temperature for longer time for the reason that the addition of Al 2 O 3 thin film can effectively prevent diffusion of oxygen in air during the heat treatment process. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen deposition is of great concern to both air quality and the ecosystem, particularly in northern China, which covers one-quarter of China's cultivated land and has many heavily air polluted cities. To understand the characteristics of wet N deposition at rural sites in northern China, one-year wet deposition samples were collected in the Daheitin reservoir region. Due to the intense emissions of gaseous nitrogen compounds from heating activities during cold seasons and distinct dilution effects under different rainfall intensities and frequencies, the volume weighted mean concentrations of wet N deposition showed higher levels in dry seasons but lower levels in wet seasons. In contrast, the wet N deposition rates varied consistently with precipitation, i.e., high during the wet season and lower during the dry season. The annual wet deposition rate of total inorganic ions (the sum of NO3−–N and NH4+–N) at the rural site in North China from July 2019 to June 2020 was observed at 18.9 kg N ha−1 yr−1, still remained at a relatively high level. In addition, biomass burning activities are ubiquitous in China, especially in northern China; however, studies on its impact on wet N deposition are limited. Non-sea salt potassium ion (nss-K+) was employed as a molecular tracer to investigate the characteristics of biomass burning activities as well as their impact on the chemical properties of wet N deposition. Three precipitation events with high nss-K+ levels were captured during the harvest season (June to July). The variations in the patterns of nss-K+, deposited N species, and ratios of nss-K+ to nitrogen species as well as their relationships all indicated that biomass burning emissions contributed remarkably to NO3−–N but had a minor influence on NH4+–N. [ABSTRACT FROM AUTHOR]

• ZrB 2 thin films can be used as low infrared emissivity layers at high temperature. • ZrB 2 thin films exhibits a low infrared emissivity of 0.01(8~14 μm) after heat treatment. • ZrB 2 thin film is a good contender to nobal metallic films. Zirconium diboride exhibits high thermal conductivities and high melting point, which are beneficial for use in extreme environments. Examples including cutting tools, high-temperature electrodes and leading edges of hypersonic space vehicles. However, there is limited literature on the infrared properties of ZrB 2 thin films. In this study, we report the results of infrared emissivity of sputter-deposited films and post-annealed films. X-ray diffraction shows promoted crystalline quality and grains growth for ZrB 2 films with the increasing annealing temperature and time. The thin film exhibits high thermal stability and a low infrared emissivity of 0.01 (8 ~ 14 μm) after annealed at 1000℃ for 10 h. Besides, with an increase in annealing temperature and annealing time, film densification and grains growth were observed, leading to decrease of electrical resistivity and infrared emissivity. [ABSTRACT FROM AUTHOR]

• Thermoelectric properties of a halide perovskite at 300–600 K are reported. • Experiments and calculations combine to provide a coherent and realistic picture. • Interconnection between individual thermoelectric parameters is revealed. • The ZT value maximized at ~0.01 and can be boosted by extrinsic doping. Halide perovskite semiconductors have been actively considered for thermoelectric applications. We report the thermoelectric properties of thermally stable, all-inorganic perovskite CsSnBr 3 prepared by two methods. Between 300 and 600 K, both types of CsSnBr 3 crystals showed analogous trends of increasing Seebeck coefficients S and plummeting electrical conductivities σ. The counteraction between S and σ followed a semilogarithmic relation derived from a single band model for the electronic band structure of CsSnBr 3. The ZT value maximized at ~0.01 and its enhancement by extrinsic doping is possible. Our results help assess the potential of CsSnBr 3 and other halide perovskites as thermoelectric materials. [ABSTRACT FROM AUTHOR]

• A novel Ca-based desulfurizing agent was developed to reduce SO 2 emission. • The desulfurizing agent was prepared from waste hardened cement mortar. • SO 2 was removed through a dissolution and precipitation process. • The SO 2 removal product could be used as raw material for cement production. Developing efficient low-cost absorbents has been recognized as a prerequisite for industrial application of wet flue gas desulfurization (WFGD). Herein, hardened cement mortar (HCM) particles developed from waste concrete blocks were used as an innovative absorbent for SO 2. The results show that the SO 2 in flue gas can be completely absorbed by the highly alkaline HCM slurry. Under optimum operating conditions, 0.8 g of SO 2 was retained by per gram of HCM. Under acid conditions produced upon dissolving SO 2 in water, the Ca-rich compounds in HCM particles can continuously release Ca2+ and OH− into the HCM slurry. The Ca2+ ions released can effectively combine with SO 3 2−, resulting in the absorption of SO 2 dissolved in water. The dissolution process of HCM particles is well described by the pseudo-second-order model. The desulphurization byproduct was characterized by X-Ray diffraction (XRD) analysis, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and energy dispersive spectrometry (EDS). The results show that the desulphurization product mainly consists of gypsum. The technology developed provides a type of new material for removing SO 2 in waste flue gas. It also offers an innovative solution for the disposal of waste concrete which is also a global environmental concern. [ABSTRACT FROM AUTHOR]

Twistacene-modified π-conjugated compounds usually possessing perfect molecular structure and tailorable optoelectronic property can decrease intramolecular and intermolecular π-stacking to a certain extent. Meanwhile, these branched macromolecules might be chosen as active layers for organic electronics. Following this direction, we design and synthesize two novel dendrimer compounds 1 and 2. Both of them emit strong blue and green fluorescence in organic solvents and thin film with high quantum yields. The fabricated OLED devices based on them showed the maximum brightness of 982 cd m−2 for device-1 and 20801 cd m−2 for device-2. Two novel twistacene-modified π-conjugated compounds containing mismatch structures exhibit promising electroluminescence. Image 1 • Two novel π-conjugated compounds with mismatch structures have been synthesized. • Both of them emit strong blue and green fluorescence in organic solvents and thin film. • The optimized devices with these compounds as emitters exhibited excellent electroluminescent performance. [ABSTRACT FROM AUTHOR]

• A hybrid composite approach is demonstrated for high energy density sodium-ion storage. • Iron sulfide/sulfurized polyacrylonitrile hybrid nanofibers were successfully synthesized as a hybrid anode material. • A flexible and free-standing anode without binder, current collector and additional conductive additives was realized. • The self-supporting anode exhibited excellent high-rate sodium-ion storage with stable cycling performance. Sodium-ion based energy storage systems have attracted extensive attention due to the similarities in the mechanism of operation with lithium-ion batteries along with the additional benefit of low cost and high abundance of sodium resources. Iron sulfide-based electrodes that operate via conversion mechanism have shown ample potential for high energy sodium-ion storage. However, the problems related with tremendous volume changes and the dissolution of sodium polysulfides in the electrolyte deteriorate the cycle life and limit their application in sodium-ion batteries (SIBs). Herein, a hybrid anode material, FeS/SPAN-HNF, with iron sulfide (FeS) nanoparticles decorated in a sulfurized polyacrylonitrile (SPAN) fiber matrix is demonstrated as flexible and free-standing anode material for high-rate SIBs. Unlike previous strategies in which FeS is encapsulated in an electrochemically inactive carbon matrix, this study utilizes SPAN, an electrochemically active material, as a dual functional matrix that can efficiently buffer volume expansion and sulfur dissolution of FeS nanoparticles as well as provide significant capacity improvement. The as-designed electrode is self-standing and flexible, without current collectors, binders or additional conductive agents, thus rendering enhanced practical capacity and energy density. This electrode showed a high reversible capacity of 782.8 mAh g−1 at 200 mA g−1 with excellent high rate capability, maintaining 327.5 mAh g−1 after 500 cycles at 5 A g−1, emphasizing promising prospects for the development of flexible and high energy density SIBs. [ABSTRACT FROM AUTHOR]

• Waste concrete powder was evaluated as a new phosphorus removal material. • Phosphorus removal efficiency of waste concrete fines varies with its particle size. • A" components separation" mechanism was discovered in waste concrete fines. • The mechanism of phosphorus removal by waste concrete powder was proposed. Reusing of fine particles of waste concrete (FPWC) is a disturbing problem for waste concrete recycling process. In this study, the FPWC developed from waste concrete was used as an innovative absorbent to remove phosphorus (P) from wastewater. The results showed, with the change of particle size of the FPWC, the maximum phosphorus binding capacity of the FPWC varies in the range of 1.07–4.96 mg P/g. The P-removal ability of FPWC increases as its particle size decreases, because of the FPWC with smaller particle size has more Ca-rich and porous hardened cement paste (HCP) powder. A "components separation" mechanism was proposed to explain the change of HCP powder content in FPWC with different particle size distribution. Both the Thomas and Yoon-Nelson model can be used to describe the P-removal behaviors of FPWC. The phosphorus removal mechanism is that the Ca2+ and OH− can release from HCP powder and forms a local alkaline condition with high Ca2+ concentration. The condition was beneficial to the formation of Ca 5 (PO4) 3 (OH) which could be attached on the surface of the FPWC. Based on the Fick's law, the Ca2+ release behavior form FPWC can be separated into two stages, and it could be described by pseudo-second order model. Totally, FPWC developed from waste concrete blocks exhibited sufficient potential in phosphate removal. [ABSTRACT FROM AUTHOR]

High-efficiency organic solar cells (OSCs) based on low-temperature (LT) processed SnO 2 electron transport layer (ETL) are promising for their commercial use. However, high density of traps and large contact barrier for carriers at the interface between LT SnO 2 and the active layer has been reported. To solve the problem, various interface modifying layer materials, such as PFN, has been introduced. Currently, the fabrication process of such interface modifying layer materials is complex and expensive. Herein, a facile strategy involved a polar solvent ethanolamine (EA) is introduced to modify LT SnO 2 surface. By soaking the SnO 2 film into EA solution in 2-Methoxyethanol (2-ME), EA can easily anchor into SnO 2 film surface and forms a continuous monomolecular layer via dehydration reaction. The whole process is green and highly compatible with a roll-to-roll process. Further study suggests that the deep trap centers on SnO 2 surface are substantially reduced and the built-in potential in OSCs is reinforced. Finally, OSCs based on EA-modified SnO 2 demonstrated an enhanced power conversion efficiency from 10.71% to 12.45% which was comparable to those based on ZnO (12.26%) under the same experiment parameters. Our work boosts the development of the inverted OSCs with easy fabrication and compatibility with roll-to-roll process. Image 1 • The EA molecules are bound to the SnO2 film surface through a dehydration reaction. • The EA treatment significantly suppresses the hydroxyl groups related deep-level traps at the SnO2/BHJ interface. • The built-in potential of OSCs is reinforced by using EA treatment at SnO2/BHJ interface. • The EA treatment boosts the efficiency of PBDB-TF:IT-4F based OSCs from 10.71% to 12.45%. [ABSTRACT FROM AUTHOR]

• Low-coherent pulse with precise temporal shaping and spectral control. • μJ-level instantaneous broadband pulse of time-spectrum independent. • Coherence time is 123 fs, much shorter than pulse duration. • Output instability less than 1% rms and 8% peak-to-valley over 4 h. A μJ-level low-coherent pulse with dynamic and precise temporal shaping and spectral control is demonstrated. Low-coherent light delivered by a superluminescent diode is precisely shaped through a wave guide amplitude modulator driven by an arbitrary waveform generator. Utilizing a three-stage axial-alternating polarization-maintaining single-mode fiber amplifier, μJ-level low-coherent pulses with 3 ns durations and 20 nm instantaneous bandwidths at a 1 kHz repetition rate are obtained. In addition, a spectral control unit is used to adjust the spectrum shape. As a result, near flat-top, saddle-type, or other required special spectra can be produced. The low temporal coherence characteristics and output stability are characterized experimentally. [ABSTRACT FROM AUTHOR]

Layered perovskite oxyhalide Bi 4 NbO 8 Cl has been reported as a stable photocatalyst for the organic pollutant removal. In this work, Bi 4 NbO 8 Cl was synthesized using liquid-combustion approach, and an efficient Ag/Bi 4 NbO 8 Cl photocatalyst was prepared via photo-deposition method. Transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS) display that metallic Ag nanoparticles (∼10 nm) are uniformly distributed on the surface of Bi 4 NbO 8 Cl. Owing to a shift of the valence and conduction band and band-gap narrowing, demonstrated by UV-vis diffuse reflection spectroscopy (UV-vis DRS) and Mott-Schottky results, the Ag/Bi 4 NbO 8 Cl show enhanced photocatalytic degradation of RhB with almost 100% within 3 h. Photogenerated holes (h+) are foremost active specie responsible for the degradation of RhB via the capture agent test. The improvement of photocatalytic performance of 3% Ag/Bi 4 NbO 8 Cl could be attributed to the synergetic effect of the surface plasmon resonance and electron sinkers by Ag nanoparticles, strengthening the visible-light absorption ability, as well as promoting the separation efficiency of charge carriers, which are beneficial for enhancing photocatalytic performance. The present work provides a promising insight into the design Bi-based photocatalysts to solve environmental pollution. • Novel Ag/Bi 4 NbO 8 Cl photocatalyst is prepared using photo-deposition method. • Plasmonic Ag can strengthen the visible-light absorption ability and enhance photocatalytic performance of layered Bi 4 NbO 8 Cl. • Ag QDs in the Ag/Bi 4 NbO 8 Cl system can act as electron trap to promote separation of the photoexcited hole-electron pairs. [ABSTRACT FROM AUTHOR]

Incorporation of new readout methods with established analytical devices allows methodological innovations in analytical sciences. Herein, we present a new sensing platform by combining an ultrasensitive element analyzer, namely the laser-induced breakdown spectroscopy (LIBS) and a lateral flow strip (LFS). Ag x Au y bimetallic nanoparticles (Ag x Au y BNPs) are selected as the labels to deliver the optimal quantitative performance by analyzing the Ag (I) signal from the test (T) line of LFS. For prototypical application in pathogen detection, the LIBS-LFS sensor can achieve a detection limit of 1.6 cfu mL−1 of Staphylococcus aureus (S. aureus) within 10 min, which is superior to conventional methods. Importantly, the signals of Ag x Au y BNPs for visual and LIBS analysis are stable and still readable after the detection is finished and the test strip is stored for up to 13 days, suggesting a potential for long-term data preservation. This combination of LIBS with LFS provides a new concept toward integrated nano/analytical devices that can benefit various application scenarios. • Quantitative performance of lateral flow strip (LFS) needs to be improved. • The laser-induced breakdown spectroscopy (LIBS) is applied to develop a LFS sensor. • LIBS is firstly applied to detect pathogen by in situ analyzing element label on LFS. • The sensor achieves a LOD of 1.6 cfu mL−1 of S. aureus within 10 min. • The LIBS signals are still readable after the detection is finished for 13 days. [ABSTRACT FROM AUTHOR]

Flowering time is an important factor that controls crop yield and latitudinal adaptation. Soybean is a facultative short-day (SD) plant, and cultivars that originate from temperate regions generally undergo a very short juvenile phase and early flowering when grown in low-latitude regions, thereby resulting in extremely low grain yield. However, introduction of the long-juvenile (LJ) trait, which extends the vegetative phase and improves yield under SD environments, has largely overcome this constraint and has enabled the expansion of soybean production to tropical regions. Quantitative trait locus (QTL) mapping is a fundamental approach to the identification of new loci related to LJ trait, while conventional strategy takes lots of time to verify the findings. Here, we provide a new strategy to rapidly identify consistent novel QTLs by using multiple genetic populations and genotyping-by-sequencing (GBS) approach. In this study, we developed six F2 populations and grew them under SD conditions. A total of seven QTLs related to the LJ trait were identified by integrating flowering time (R1) and high-density genetic maps. There were three consistent QTLs repeatedly detected in different populations and one of them has been previously reported, yet two are novel. This research not only provides fundamental resources for fine-mapping candidate genes associated to the LJ trait, but also provides new insights to QTL mapping. [ABSTRACT FROM AUTHOR]

A highly sensitive and flexible hydrogen sensor based on organic nanofibers decorated by Pd nanoparticles (NPs) was designed and fabricated for low-concentration hydrogen detection. Pd NPs were deposited on organic nanofiber materials by DC magnetron sputtering. The temperature dependence of the sensitivity at 25 ppm H2 was characterized and discussed, and the maximum response of the sensor increased linearly with increasing measurement temperature. Performances of the hydrogen sensor were investigated with hydrogen concentration ranging from 5 ppm to 50 ppm. This sensor exhibits high sensitivity, with the response up to 6.55% for H2 as low as 5 ppm, and the output response of the hydrogen sensor increased linearly with the square root of hydrogen concentration. A cycling test between pure nitrogen and 25 ppm hydrogen concentration was performed, and the hydrogen sensor exhibited excellent consistency. [ABSTRACT FROM AUTHOR]

The PdNi film hydrogen sensors with Wheatstone bridge structure were designed and fabricated with the micro-electro-mechanical system (MEMS) technology. The integrated sensors consisted of four PdNi alloy film resistors. The internal two were shielded with silicon nitride film and used as reference resistors, while the others were used for hydrogen sensing. The PdNi alloy films and SiN films were deposited by magnetron sputtering. The morphology and microstructure of the PdNi films were characterized with X-ray diffraction (XRD). For efficient data acquisition, the output signal was converted from resistance to voltage. Hydrogen (H2) sensing properties of PdNi film hydrogen sensors with Wheatstone bridge structure were investigated under different temperatures (30 °C, 50 °C and 70 °C) and H2 concentrations (from 10 ppm to 0.4%). The hydrogen sensor demonstrated distinct response at different hydrogen concentrations and high repeatability in cycle testing under 0.4% H2 concentration. Towards 10 ppm hydrogen, the PdNi film hydrogen sensor had evident and collectable output voltage of 600 μV. [ABSTRACT FROM AUTHOR]

Because they generate excellent images, nanoparticles (NPs), especially biosynthesized NPs, provide a new solution for tumor imaging. In this research, we unveil a novel type of biosynthesized NPs featuring multicolor fluorescence. These NPs exhibit little cytotoxicity to cells. The explored NPs, designated Zn-ZFP-GST NPs (Zinc NPs in abbreviation), are generated from leukemia cells treated with a Zn2+ solution, while zinc-finger protein and glutathione S-transferase (GST) were also identified in the Zinc NPs. Under near-UV illumination, the Zinc NPs simultaneously emit green, yellow, and red fluorescence. In addition, the intensity of the fluorescence increases with the existence of sulfides. Besides, the NPs are encapsulated by microvesicles (MVs) shed from the plasma membrane. As observed in whole-body research of nude mice, the NP-MVs migrate via blood circulation and are distinguished by their fluorescent signals. Furthermore, the folic acid (FA) &AVR2 (human VEGF antibody)-coated NP-MVs are exploited to target the tumor location, and the feasibility of this approach has been confirmed empirically. The Zinc NPs shed light on an alternative solution to tumor detection. [ABSTRACT FROM AUTHOR]