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Cu2ZnSnS4xSe4(1-x) (CZTSSe) has recently attracted much attention for solar water splitting due to its high absorption efficient and tunable bandgap. However, high quality CZTSSe thin films with good quality and adherence with the substrate are mainly based on physical deposition method, such as magnetron sputtering, which is expensive and energy consuming processes. Here, we have developed a novel and low-cost solution fabrication method and CZTSSe electrodes were synthesized at low temperature by hydrothermal treatment of chemical bath deposited SnS films. The quality and phase purity of CZTSSe thin films were greatly improved after annealing process and the effect of SnS thickness to the physical and photoelectrochemical (PEC) properties of CZTSSe thin films were detailedly studied. The fabrication of FTO/CZTSSe/CdS/TiO2/Pt photocathode improved the PEC properties of CZTSSe thin films greatly and the highest water splitting photocurrents of 7.2 mA/cm−2 had been achieved under simulated solar illumination. Furthermore, the electrode showed good stability and had a good incident photon-to-current efficiency (IPCE) response in the visible light range.

Maintaining Na+ /K+ homeostasis is a critical feature for plant survival under salt stress, which depends on the operation of Na+ and K+ transporters. Although some K+ transporters mediating root K+ uptake have been reported to be essential to the maintenance of Na+ /K+ homeostasis, the effect of K+ long-distance translocation via phloem on plant salt tolerance remains unclear. Here, we provide physiological and genetic evidence of the involvement of phloem-localized OsAKT2 in rice salt tolerance. OsAKT2 is a K+ channel permeable to K+ but not to Na+ . Under salt stress, a T-DNA knock-out mutant, osakt2 and two CRISPR lines showed a more sensitive phenotype and higher Na+ accumulation than wild type. They also contained more K+ in shoots but less K+ in roots, showing higher Na+ /K+ ratios. Disruption of OsAKT2 decreases K+ concentration in phloem sap and inhibits shoot-to-root redistribution of K+ . In addition, OsAKT2 also regulates the translocation of K+ and sucrose from old leaves to young leaves, and affects grain shape and yield. These results indicate that OsAKT2-mediated K+ redistribution from shoots to roots contributes to maintenance of Na+ /K+ homeostasis and inhibition of root Na+ uptake, providing novel insights into the roles of K+ transporters in plant salt tolerance.

The well-known "shuttle effect" of the intermediate lithium polysulfides (LiPSs) and low sulfur utilization hinder the practical application of lithium-sulfur (Li-S) batteries. Herein, we describe a novel C60 -S supramolecular complex with high-density active sites for LiPS adsorption that was formed by a simple one-step process as a cathode material for Li-S batteries. Benefiting from the cocrystal structure, 100 % of the C60 molecules in the complex can offer active sites to adsorb LiPSs and catalyze their conversion. Furthermore, the lithiated C60 cores promote internal ion transport inside the composite cathode. At a low electrolyte/sulfur ratio of 5 μL mg-1 , the C60 -S cathode with a sulfur loading of 4 mg cm-2 exhibited a high capacity of 809 mAh g-1 (3.2 mAh cm-2 ). The development of the C60 -S supramolecular complex will inspire the invention of a new family of S/fullerenes as cathodes for high-performance Li-S batteries and extend the application of fullerenes.

A highly sensitive and selective electrochemical chiral sensor was developed based on the competitive supramolecular interaction of carbon nanofibers (CNFs) embedded sulfobutyl ether-β-cyclodextrin (SBE-β-CD) with optically active cationic drugs at glassy carbon electrode (GCE). The difference in intermolecular hydrogen bonding/stability constant/enantioselectivity coefficient and Gibbs free energy of anionic host SBE-β-CD with enantiomers of amlodipine (R-/S-AML), clenbuterol (R-/S-CBL) and metoprolol (R-/S-MET) as a guest paved the way for efficient discrimination. The proposed sensing platform (CNFs-SBE-β-CD/GCE) could recognize the aforementioned enantiomers based on the discernible difference of peak potential (S/R-AML (ΔEp = 135 mV), R/S-MET (ΔEp = 99 mV) and R/S-CBL (ΔEp = 111 mV). The binding mechanisms and thermodynamic study of the enantiospecific behavior have been investigated using the host-guest chemistry approach inside the nanocavity and results suggest that S-AML, R-MET, and R-CBL show stronger stability constants than their antipodes. Formation of the diastereomeric complex was taken as a measure of enantioselectivity and experimental results indicated that anionic SBE-β-CD is a better chiral ligand than neutral cyclodextrins. The fabricated sensor could be a useful low-cost electrochemical tool for molecular recognition of a variety of cationic species not only of drugs but also from other sources.

Pure organic multi-color luminescent materials were developed using a supramolecular complex strategy based on a high-efficiency blue-emitting anthracene derivative, in which the emission color can be finely tuned from blue through green to red due to the different co-former compositions and stacking modes in the crystal. Experimental and theoretical investigations demonstrate that the excited-state characteristics are essentially responsible for multi-color fluorescence emission with tunable lifetime and efficiency, corresponding to the different excited-state species (e.g., monomer, excimer-like aggregate and exciplex) in the crystals, respectively. Meanwhile, these supramolecular complexes exhibit intriguing mechanochromic and solvent-induced luminescence switching in the stimuli-responsive field. This work not only provides a better understanding of the structure–property relationship between intermolecular complexes and fluorescence properties, but also suggests a feasible strategy to develop a new class of organic solid-state luminescent materials with multi-color fluorescence.

Sulfurized polyacrylonitrile (SPAN) as a promising cathode material for lithium sulfur (Li-S) batteries has drawn increasing attention for its improved electrochemical performance in carbonate-based electrolyte. However, the relatively poor electronic and ionic conductivities of SPAN limit its high-rate and low-temperature performances. In this work, a novel one-dimensional nanofiber SPAN (SFPAN) composite is developed as the cathode material for Li-S batteries. Benefitting from its one-dimensional nanostructure, the SFPAN composite cathode provides fast channels for the migration of ions and electronics, thus effectively improving its electrochemical performance at high rates and low temperature. As a result, the SFPAN maintains a high reversible specific capacity ~ 1200 mAh g−1 after 400 cycles at 0.3 A g−1 and can deliver a high capacity of ~ 850 mAh g−1 even at a high current density of 12.5 A g−1. What is more, the SFPAN can achieve a capacity of ~ 800 mAh g−1 at 0 °C and ~ 1550 mAh g−1 at 60 °C, thus providing a wider temperature range of applications. This work provides new perspectives on the cathode design for high-rate lithium-sulfur batteries.

Summary An ultrasonic imaging technique has been developed to investigate the internal changes of pouch cells nondestructively. The local ultrasonic transmittance of pouch cells has been measured and used for imaging with a new ultrasonic scanning machine designed and built in-house. The wetting process of the cells is clearly observed via such ultrasonic imaging techniques. Furthermore, ultrasonic transmission images of fresh cells and aged cells with different electrolytes and cycling conditions exhibit very different ultrasonic transmittance, which can be caused by electrolyte dry-out or “unwetting” due to cell swelling. The ultrasonic imaging technique is a very sensitive method to probe failure mechanisms in Li-ion pouch cells.

Strawberry (Fragaria × ananassa) is an ideal model plant for studies on non-climacteric fruit ripening. Although much progress has been made towards understanding the molecular mechanism of strawberry fruit ripening regulated by abscisic acid (ABA), little is known about the interactions between members of the FaPYR/PYL and FaPP2C families. Here, using RNA-seq, qPCR, and yeast two-hybrid analyses, we found that the FaPYR/PYL and FaPP2C gene families both have nine members, respectively, among which FaPYL2/4/8/9/11/12 and FaABI1/FaPP2C16/51/16L2/16L1/37 showed relatively higher expression at the mRNA level during ripening. The transcript abundance of candidate members of the FaPYR/PYLs and FaPP2Cs families tended to increase and decrease, respectively, at the onset of fruit reddening. In phylogenetic analyses, FaPYL2, FaPYL4, FaPYL11/FaPYL12, and FaPYL8/FaPYL9 were classified into four subgroups, and FaABI1/FaPP2C16/FaPP2C16L/FaPP2C6, FaPP2C24/FaPP2C37, and FaPP2C8/FaPP2C51 were classified into three subgroups. In yeast two-hybrid analyses, FaPYL4/9/11 and FaABI1/FaPP2C16 were able to interact with each other. ABA could not promote interactions between un-interacted pairs of FaPYL2/8/12 and FaPP2C16/51/37. FaABI1 and FaPYL2 interaction may play a major role in ripening. This is the first report on the analysis of interactions between members of the FaPYR/PYLs and FaPP2Cs families in strawberry. The results provide insights into ABA signal transduction during non-climacteric fruit ripening.

Many nonlinear vibrations arising in the engineering of architecture include noise and uncertain properties, and this paper suggests a fractional model to elucidate the properties. The fractional sine-Gordon equation with the Riemann–Liouville fractional derivative is used as an example to solve its periodic solution by the homotopy perturbation method. The frequency–amplitude relationship is obtained, and the effect of the fractional derivative order on the vibration property is discussed. Additionally, the harmonic resonance is also discussed. This preliminary research can be further extended to real applications.

The plant Shaker K+ channel AtAKT2 has been identified as a weakly rectifying channel that can stabilize membrane potentials to promote photoassimilate phloem loading and translocation. Thus, studies on functional characterization and regulatory mechanisms of AtAKT2-like channels in crops are highly important for improving crop production. Here, we identified the rice OsAKT2 as the ortholog of Arabidopsis AtAKT2, which is primarily expressed in the shoot phloem and localized at the plasma membrane. Using an electrophysiological assay, we found that OsAKT2 operated as a weakly rectifying K+ channel, preventing H+ /sucrose-symport-induced membrane depolarization. Three critical amino acid residues (K193, N206, and S326) are essential to the phosphorylation-mediated gating change of OsAKT2, consistent with the roles of the corresponding sites in AtAKT2. Disruption of OsAKT2 results in delayed growth of rice seedlings under short-day conditions. Interestingly, the lipid second messenger phosphatidic acid (PA) inhibits OsAKT2-mediated currents (both instantaneous and time-dependent components). Lipid dot-blot assay and liposome-protein binding analysis revealed that PA directly bound with two adjacent arginine residues in the ANK domain of OsAKT2, which is essential to PA-mediated inhibition of OsAKT2. Electrophysiological and phenotypic analyses also showed the PA-mediated inhibition of AtAKT2 and the negative correlation between intrinsic PA level and Arabidopsis growth, suggesting that PA may inhibit AKT2 function to affect plant growth and development. Our results functionally characterize the Shaker K+ channel OsAKT2 and reveal a direct link between phospholipid signaling and plant K+ channel modulation.

Summary Large-scale energy storage batteries are crucial in effectively utilizing intermittent renewable energy (such as wind and solar energy). To reduce battery fabrication costs, we propose a minimal-design stirred battery with a gravity-driven self-stratified architecture that contains a zinc anode at the bottom, an aqueous electrolyte in the middle, and an organic catholyte on the top. Due to the solubility difference, the positive redox species are strictly confined to the upper organic catholyte. Thus, self-discharge is eliminated, even when the battery is stirred to realize high-rate charge-discharge. Moreover, the battery intrinsically avoids electrode deterioration and failure related to membrane crossover suffered by other types of cells. Therefore, it exhibits excellent cycling stability, which is promising for long-term energy storage.

A novel actinomycete, designated strain NEAU-Ht49T, was isolated from sea sand sampled in Sanya and characterized by using a polyphasic approach. The 16S rRNA gene sequence analysis showed that strain NEAU-Ht49T was most closely related to Actinomadura rhizosphaerae SDA37T (98.8 %), Actinomadura logoneensis NEAU-G17T (98.6 %), Actinomadura oligospora ATCC 43269T (98.6 %) and Actinomadura gamaensis NEAU-Gz5T (98.6 %). The results of phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain NEAU-Ht49T formed a cluster with A. rhizosphaerae SDA37T, A. logoneensis NEAU-G17T, A. oligospora ATCC 43269T, A. gamaensis NEAU-Gz5T and Actinomadura rupiterrae CS5-AC15T (96.4 %). Meso-diaminopimelic acid was detected in its cell walls and glucose, madurose, mannose and ribose were detected in whole-cell hydrolysate. The polar lipids were found to consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositolmannoside and two unidentified lipids. The majoy menaquinone was MK-10(H6) and the minor menaquinones were MK-9(H4) and MK-9(H8). The major fatty acids were C16 : 0, C18 : 1ω9c, 10-methyl C18 : 0 and iso-C16 : 0. Moreover, morphological and chemotaxonomic characteristics of properties of strain NEAU-Ht49T also confirmed the affiliation of the isolate to the genus Actinomadura . However, DNA–DNA relatedness, physiological and biochemical data showed that strain NEAU-Ht49T could be distinguished from its closest relatives. Therefore, strain NEAU-Ht49T represents a novel species of the genus Actinomadura , for which the name Actinomadura harenae sp. nov. is proposed, with strain NEAU-Ht49T (=CGMCC 4.7499T=JCM 32659T) as the type strain.

A novel actinobacterium, designated strain NEAU-GS14T, was isolated from soil of a flower bed in a residential area in Sanya, Hainan Province, China, and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics of the strain coincided with members of the genus Herbidospora. The 16S rRNA gene sequence analysis showed that strain NEAU-GS14T belongs to the genus Herbidospora and was most closely related to Herbidospora daliensis JCM 18061T (98.8 %), other type strains of species of the genus Herbidospora were found to be less than 98.7 %. Phylogenetic analysis using the 16S rRNA gene sequences showed that the strain formed a cluster with Herbidospora daliensis JCM 18061T. Cell wall contained meso-diaminopimelic acid as the major diamino acid and the whole-cell hydrolysates were glucose, madurose and ribose. The major polar lipids were diphosphatidylglycerol, hydroxyphosphatidylethanolamine, phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphoglycolipids and two phosphatidylinositol mannosides. The predominant menaquinone was MK-10(H4). Major fatty acids were 10-methly C17 : 0 and C17 : 0, these chemotaxonomic data supported the affiliation of strain NEAU-GS14T to the genus Herbidospora . The DNA G+C content was 70.6 mol%. Furthermore, the strain could be clearly distinguished by digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values and some phenotypic characteristics. Therefore, it is proposed that strain NEAU-GS14T represents a novel species of the genus Herbidospora , for which the name Herbidospora galbida sp. nov. is proposed. The type strain is NEAU-GS14T (=CCTCC AA 2018040T=JCM 33459T).

Fe-doped ZnO (Fe–ZnO) mesoporous nanoparticles have been synthesized via a facile hydrothermal method, which utilizes pluronic triblock copolymer polyethylene glycol–polypropylene glycol–polyethylene glycol (PEO-PPO-PEO) as the pore-forming agent. Fe–ZnO composites have an unique porous structure. Their pore sizes increase with Fe-doping concentration and reach a maximum as Fe concentration is 15 at.%; the specific surface area of synthesized mesoporous Fe–ZnO nanoparticles reaches a maximum as the Fe concentration is about 11 at.%. Electron microscopy, vapor pressure isotherm measurements and photoluminescence (PL) were used to characterize synthesized Fe–ZnO composites. Fe–ZnO-based gas sensors exhibit excellent response in detecting ethanol; the sensing response of Fe(11 at.%)–ZnO reaches 319.8, which is significantly higher than most of the ZnO-based gaseous sensors. The improved sensitivity is ascribed to the increase of oxygen-related defects and specific surface area of Fe–ZnO composites.

A novel actinobacterium, designated strain NEAU-C40T, was isolated from the rhizosphere soil of rice (Oryza sativa L.) collected from Northeast Agricultural University in Harbin, Heilongjiang province, north-east PR China, and was characterized using a polyphasic approach. On the basis of results of 16S rRNA gene sequence analysis, strain NEAU-C40T belongs to the genus Streptomyces , and shares highest sequence similarities with Streptomyces polygonati CGMCC 4.7237T (97.9%) and Streptomyces abietis DSM 42080T (97.9%). Morphological and chemotaxonomic characteristics of the strain also supported its assignment to the genus Streptomyces . Cell walls contained ll-diaminopimelic acid and the whole-cell hydrolysates were glucose, rhamnose and ribose. The major menaquinones were identified as MK-9(H8) and MK-9(H6). The major fatty acids were iso-C16:0, anteiso-C15:0, C16:0 and anteiso-C17:0. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside and an unidentified lipid. The genomic DNA G+C content of strain NEAU-C40T was 71.8 mol%. Moreover, multilocus sequence analysis based on five other housekeeping genes (atp D, gyr B, rpo B, rec A and trp B) and the low level of DNA–DNA relatedness allowed the isolate to be differentiated from its most closely related strains. On the basis of phenotypic, genotypic and phylogenetic data, strain NEAU-C40T can be characterized to represent a novel species of the genus Streptomyces , for which the name Streptomyces oryziradicis sp. nov. is proposed. The type strain is NEAU-C40T (=DSM 107943T=CCTCC AA 2018038T).

The development of high-energy-density lithium-oxygen batteries (LOBs) is hindered by the poor stability of lithium metal anodes. Lithium fluoride (LiF) was reported as an effective solid-electrolyte interface (SEI) component to enhance the stability of lithium anodes. It is desirable to improve the quality of LiF based SEIs to bear the volume expansion during the cycling process. In this work, a uniform and highly dense LiF-rich artificial SEI consisting of LiF nanoparticles close to Li with organic sulfonates wrapped on the outside is fabricated on a Li surface via the reaction of a fluorinated agent perfluorooctanesulfonyl fluoride (PFOSF) with lithium hydroxide. The reaction conditions are mild and the formed dense and insulating LiF-rich layer can prevent the thickening of the SEI film during cycling. With such a PFOSF treatment, the interface stability of lithium anodes is largely improved. The lithium dendrite growth is significantly suppressed and the corrosion in O2-rich electrolytes is alleviated. The PFOSF treated Li‖Li cells show stable polarization voltage and long cycle life up to 1700 h in an Ar and 900 h in an O2 atmosphere. Moreover, the Li–O2 battery with the PFOSF treated lithium anode shows excellent cyclability up to 185 cycles at a fixed capacity of 1000 mA h g−1, which is more than 4 times longer than that of pristine Li anodes.

Di(2-ethylhexyl) phthalate (DEHP) is a widespread environmental contaminant, which is mainly used as a plasticizer to improve the flexibility of products; however, its extensive use causes male reproductive damage. Lycopene (LYC) has a protective effect on male reproductive toxicity. Nevertheless, the underlying role of LYC in DEHP-induced spermatogenic cell damage remains unclear. Our study aimed to investigate the role of LYC in DEHP-induced spermatogenic cell damage and its underlying mechanism. Male ICR mice were treated with LYC (5 mg kg-1) and/or DEHP (500 mg kg-1 or 1000 mg kg-1) for 28 days. The results showed that LYC alleviated the DEHP-induced decrease in mitochondria volume density and mitochondrial membrane potential (ΔΨm). Subsequently, LYC prevented the DEHP-induced PGC-1α-mediated reduction in mitochondrial biogenesis in spermatogenic cells. LYC exhibited a potential preventive effect against DEHP-induced mitophagy caused by mitochondrial dynamics disorder in the spermatogenic cells. Meanwhile, LYC relieved DEHP-induced mitochondrial stress in the spermatogenic cells by activating UPRmt. These results proved that mitochondrial quality control may be related to the beneficial role of LYC in preventing DEHP-induced mitophagy in spermatogenic cells. This study provides new evidence of mitochondrial quality control as a target for LYC treatment, which can prevent DEHP-induced toxicity.

We report a terahertz quantum-cascade vertical-external-cavity surface-emitting laser (QC-VECSEL) emitting around 1.9 THz with up to 10% continuous fractional frequency tuning of a single laser mode. The device shows lasing operation in pulsed mode up to 102 K in a high-quality beam, with the maximum output power of 37 mW and slope efficiency of 295 mW/A at 77 K. Challenges for up-scaling the operating wavelength in QC metasurface VECSELs are identified.

The interfacial instability of lithium (Li) metal is one of the critical challenges, which hinders the application of rechargeable Li metal batteries (LMBs). Designing facile and effective surface/interface is extremely important for practical LMBs manufacturing. Here, a highly stable Li anode with silver nanowires sowed in the patterned ditches via a simple calendaring process is developed. The remarkably increased electroactive surface area and the superior lithiophilic Ag seeds enable Li stripping/plating mainly inside the ditches. Benefitting from such unique structural design, the ditches‐patterned and Ag‐modified composite Li anode (D‐Ag@Li) achieves excellent cyclability under 2 mA cm−2 / 4 mAh cm−2 over 360 h cycling with low nucleation overpotential of 16 mV. Pairing with the D‐Ag@Li anode, the full cells with LiNi0.8Mn0.1Co0.1O2 and LiFePO4 (LFP) cathodes achieve long cycle life with 94.2% retention after 2000 cycles and 74.2% after 4000 cycles, respectively. Moreover, ultrasonic transmission mapping shows no gas generation for the LFP pouch full cell pouch cell based on D‐Ag@Li over prolonged cycling, demonstrating the feasibility and effectiveness of the authors' strategy for LMBs., A highly stable lithium (Li) anode with silver nanowires (AgNWs) sowed in the patterned ditches is developed. The interconnected ditches significantly enhance the surface area of Li metal, and at the same time, AgNWs can serve as preferred electrochemical active sites to induce homogeneous Li nucleation and growth from the bottom rather than the top surfaces.

As a plasticizer, di(2-ethylhexyl) phthalate (DEHP) is the most usually used phthalate. Leydig cell is a male-specific cell, which plays a principal role in spermatogenesis and masculinization by the androgens of synthesis and secretion. Numerous researchers have indicated that DEHP can result in testicular toxicity by inducing oxidative stress. Lycopene (LYC) is a possible treatment option for male infertility due to its natural antioxidant properties. Our study was aimed to investigate whether LYC could rescue DEHP-induced Leydig cell damage. The mice were treated with DEHP (500 mg/kg BW/day or 1000 mg/kg BW/day) and/or LYC (5 mg/kg BW/day) for 28 days. We found that LYC attenuated DEHP-induced Leydig cell damage. Moreover, the protective role of LYC was verified by the histopathological and ultrastructural analysis of the Leydig cell. LYC suppressed oxidative stress that was induced by DEHP. In the Leydig cell, the expressions of the nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target genes were improved through LYC-mediated protection in DEHP-induced Leydig cell damage. Our findings indicated that LYC could increase the antioxidant capacity via mediating Nrf2 signaling pathway, thereby attenuating DEHP-induced Leydig cell damage.

Organic solid-state luminescent materials with high-efficiency deep-red emission have attracted considerable interest in recent years. Constructing donor-acceptor (D-A) type molecules has been one of most commonly used strategies to achieve deep-red emission, but it is always difficult to achieve high photoluminescence (PL) quantum yield (ηPL) due to forbidden charge-transfer state. Herein, we report a new D-A type molecule 4-(7-(4-(diphenylamino)phenyl)-9-oxo-9H-fluoren-2-yl)benzonitrile (TPA-FOCN), deriving from donor-acceptor-donor (D-A-D) type 2,7-bis(4-(diphenylamino)phenyl)-9H-fluoren-9-one (DTPA-FO) with a fluorescence maximum of 627 nm in solids. This molecular design enables a transformation of acceptor from fluorenone (FO) itself to 4-(9-oxo-9H-fluoren-2-yl)benzonitrile (FOCN). Compared with DTPA-FO, the introduction of cyanophenyl not only shifts the emission of TPA-FOCN to deep red with a fluorescence maximum of 668 nm in solids, but also maintains the high ηPL of 10%. Additionally, a solution-processed non-doped organic light-emitting diode (OLED) was fabricated with TPA-FOCN as emitter. TPA-FOCN device showed a maximum luminous efficiency of 0.13 cd/A and a maximum external quantum efficiency (EQE) of 0.22% with CIE coordinates of (0.64, 0.35). This work provides a valuable strategy for the rational design of high-efficiency deep-red emission materials using cyanophenyl as an ancillary acceptor.

The rotary valve speed control, extremely affected by nonlinear dependence of rotary valve load torque on rotation angle, affects the generation of drilling fluid pressure PSK signal and its quality. Based on load torque calculation model, the load torque feed forward compensation is used in linearized correction of rotation speed control system to enable the motor voltage to vary according to the calculation model. Additionally, the calculation model is also used in compensating the influence of serious nonlinearity in rotary valve load torque on rotation speed control. By means of closed-loop proportional-integral-derivative (PID) control which is formed by negative feedback of speed and the PID parameter values determination rule which is created by attenuating control of transient component in step response of rotary valve speed, the rapid servo control of rotary valve speed is realized. Simulink Simulation indicates that the closed-loop speed control system of rotary valve is able to track the change of control voltage pulse quickly and strongly suppress the interference influences from flow measurement error and load torque calculation model deviation.

In this paper we focus on the convergence and quasi-optimality of an adaptive finite element method for elliptic Robin boundary control problems. We use piecewise linear finite elements to approximate the state and the adjoint state variables, and the variational discretization to approximate the control variable. Under mild assumption on the initial mesh, we prove the contraction property, for the sum of the energy errors of the state and adjoint state and the scaled error estimator, on two consecutive adaptive loops. The resulting linear convergence yields the quasi-optimal convergence rate for the AFEM algorithm applied to our problem. Additionally, some numerical results are provided to support our theoretical analysis.

An elliptical region was observed on the wafer cut from the ingot along (1 1 1) face after etching and the ingot was grown by the Vertical Bridgman method. The wafers with the elliptical region were characterized with zinc concentration distribution scanner and infrared transmission microscope. Infrared transmission images revealed the morphology evolution of Te inclusions from irregular droplets to regular tetrahedrons and different stages from the Te-rich threads to the pearl-string Te inclusions inside the elliptical region. Te atoms preferentially diffused and aggregated in the dislocation direction, which resulted in the formation of Te-rich droplets and Te-rich threads. The Zn component map indicated that Zn concentration varied significantly at the elliptical boundary, the Zn concentration inside the ellipse was lower than other normal region. Based on the above experiments, it was considered that such an elliptical region created because of the occurrence of constitutional supercooling, in other words, it is caused by a drastic change of the Zn concentration gradient in the liquid phase at the front of the solid-liquid interface. The segregation of the Zn concentration in the liquid phase at the front of the interface was related to the growth rate. During crystal growth, when approaching the region where the Zn concentration changed drastically, the growth rate should be appropriately lowered to meet the normal Zn concentration gradient to avoid the generation of elliptical region.

Although Li-air batteries have superhigh theoretical energy density, their practical application is still a big challenge especially when operated in regular air. At this point, it is crucial to avoid side reactions induced by the moisture in the air. Thus, an oxygen selectively permeable membrane is desirable. Herein, we introduce an oxygen-permeating waterproof membrane based on perfluoropolyether (PFPE), a non-volatile hydrophobic liquid compound with high oxygen solubility. With protection of the PFPE-wetted Celgard membrane, the stability of both lithium metal and lithium peroxide is significantly improved. Meanwhile, the evaporation of organic electrolyte solvent is greatly suppressed. As a result, the Li-air cell is able to run 144 cycles over 58 days in ambient air with ~ 30% relative humidity.

WOS: 000473379500038, To reduce the tank mixture leftover problem associated with variable-rate orchard sprayers, an experimental automatic premixing in-line injection system was developed with Arduino platform. This system primarily consisted of a precision fluid metering pump, a water pump, a static mixer, a premixing tank and a buffer tank. The required amounts of water and chemical concentrates were accurately pumped into the premixing tank through a static mixer. The mixture was then transferred into a buffer tank for additional mixing process and for the spray pump to discharge to variable flow-rate nozzles. When the buffer tank neared empty, this process was repeated automatically to maintain the same chemical ratio for all nozzles regardless of their spray output differences and variations. Accuracy of the metering pump was verified with simulated pesticide concentrates (tap water, turpentine oil, prime oil, and four different viscous sucrose solutions) at viscosities between 0.9 and 32.0 mPa.s. With addition of a fluorescent tracer, the sucrose solutions were also used to evaluate the uniformity of spray mixtures discharged from the premixing in-line injection system. Test results demonstrated that the fluid metering pump could accurately dispense desired volume (10-300 mL) of simulated pesticides at different pump rotational speeds with relative errors between measured and desired volumes below 5%. The uniformity of spray mixtures at different chemical-to-water ratios (0.1%-2.0%) was consistent, and the highest relative error and coefficient of variation were 7.6% and 4.5%, respectively. The experimental premixing in-line injection system was proven to have stable and accurate performance, and thus would have great potentials to improve spray application efficiency with minimized tank mixture leftovers for future variable-rate sprayers., USDA-NIFA Specialty Crop Research Initiative [2015-51181-24253], Mention of company or trade names is for description only and does not imply endorsement by the USDA. The USDA is an equal opportunity provider and employer. The authors acknowledge invaluable technical assistance from Adam Clark, Barry Nudd, Andy Doklovic and Greg Smith. We are also grateful to the USDA-NIFA Specialty Crop Research Initiative (Grant No. 2015-51181-24253) for funding this research.

Aqueous batteries are suitable for large scale energy storage due to cost and safety concerns. Among all aqueous batteries, rechargeable aqueous zinc-ion battery is a promising choice because zinc electrode has low equilibrium potential, high exchange current density, and high hydrogen evolution overpotential. However, since zinc ion is a divalent cation, it is difficult to find a cathode material in which zinc ion can reversibly insert and extract. In this work, we introduce a novel V2O5 nanopaper consisting of V2O5 nanofibers and carbon nanotubes as reversible Zn-ion cathode. V2O5 has a layered crystalline structure. The spaces between the oxide layers may serve as 2-dimensional diffusion pathways for Zn ions. Meanwhile, the nanofiber morphology endows the material with short ionic diffusion distance and may tolerate high volume change. As a result, the V2O5 nanopaper cathode delivers a high capacity of 375 mAh g−1 and long cycle life up to 500 cycles.

Core-shell nanomaterials (CSNs) have achieved huge popularity due to multifunctional properties achieved by manipulation of core or shell materials. This review highlights recent development in CSNs based sensing devices such as electrochemical sensors, optical sensors, wearable sensing devices, and gas adsorptive sensors, which find potential applications in numerous fields ranging from industrial, clinical, biological, environmental and food analysis. Furthermore, flexible and high deformation monitoring piezoresistive wearable sensors based on CSNs are found to be promising for monitoring of human physiological parameters and other body movements. Various synthetic strategies with a modern classification approach are explained with suitable examples. Several interesting properties of CSNs including high surface area, high conductivities, and high ion transport properties with biocompatibilities are best suited for developing ideal sensing devices. Future research directions with motivated research are highlighted in the conclusion part.

To achieve high-efficiency red excimer fluorescence, two novel perylene (PE) derivatives (mTPA-3PE and 2SF-3PE) are designed and synthesized with different monosubstituent triphenylamine (TPA) and spirofluorene (SF), respectively. The photophysical investigations reveal that mTPA-3PE and 2SF-3PE exhibit red/orange-red excimer fluorescence (637 and 610 nm) with long lifetimes (37.86 and 72.41 ns) in crystals but significantly different photoluminescence efficiencies (24 and 77%). Both crystal structure and excited-state property emphasize that the discreteness of the PE dimer with π–π stacking is essentially responsible for the high-efficiency excimer emission in the crystal. Using PE as a π–π emissive core in this work, highly efficient red excimer fluorescence is harvested in the crystal for the first time. Moreover, their nanoparticles with the same excimer fluorescence exhibit the advantage of easy processing and the promising application in cell imaging. Once again, our results validate the mechanism ...

In order to analyze two basic characteristic acoustic parameters of activated carbon fiber felts: propagation constant and characteristic impedance, the theoretical model of characteristic ...

Conventional techniques to synchronize bacterial cells often require manual manipulations and lengthy incubation lacking precise temporal control. An automated microfluidic device was recently developed to overcome these limitations. However, it exploits the stalk property of Caulobacter crescentus that undergoes asymmetric stalked and swarmer cell cycle stages and is therefore restricted to this species. To address this shortcoming, we have engineered Escherichia coli cells to adhere to microchannel walls via a synthetic and inducible "stalk". The pole of E. coli is capped by magnetic fluorescent nanoparticles via a polar-localized outer membrane protein. A mass of cells is immobilized in a microfluidic chamber by an externally applied magnetic field. Daughter cells are formed without the induced stalk and hence are flushed out, yielding a synchronous population of "baby" cells. The stalks can be tracked by GFP and nanoparticle fluorescence; no fluorescence signal is detected in the eluted cell population, indicating that it consists solely of daughters. The collected daughter cells display superb synchrony. The results demonstrate a new on-chip method to synchronize the model bacterium E. coli and likely other bacterial species, and also foster the application of synthetic biology to the study of the bacterial cell cycle.

SnS has been widely used in photoelectric devices due to its special band gap of 1.2–1.5 eV. Here, we reported on the fabrication of SnS nanosheets and the effect of synthesis condition together with heat treatment on its physical properties. The obtained band gap of the SnS nanosheets is in the rage of 1.37–1.41 eV. It was found that the photo-current density of a thin film comprised of SnS nanosheets could be enhanced significantly by annealing treatment. The maximum photo-current density of the stack structure of FTO/SnS/CdS/Pt was high as 389.5 μA cm−2, rendering its potential application in high efficiency solar hydrogen production.

High quality CdZnTe films were deposited on polished CdZnTe film, Si wafer and fluorine doped tin oxide (FTO) glass by close spaced sublimation (CSS) method. The influences of different substrates on the growth rate, composition, structural and electrical properties of CdZnTe films were investigated. The results showed that the CdZnTe film prepared on the polished CdZnTe film substrate had a higher growth rate and a better crystalline quality. The film prepared on the polished CdZnTe film substrate also exhibited lower leakage current, which is promising for high energy particle detection.

Characterization of structural differences between coexisting conformational states of protein is difficult with conventional biophysical techniques. Hydrogen/deuterium exchange (HDX) coupled with top-down mass spectrometry (MS) allows different conformers to be deuterated to different extents and distinguished through gas-phase separation based on molecular weight distributions prior to determination of deuteration levels at local sites for each isolated conformer. However, application of this strategy to complex systems is hampered by the interference from conformers with only minor differences in overall deuteration levels. In this work, we performed differential HDX while the different conformers were separated according to their differing charge to size ratios in capillary electrophoresis. Mixtures of holo- and apo-myoglobin (Mb) and disulfide isomers of lysozyme (Lyz) were characterized in a conformer-specific fashion using this strategy, followed by conformation interrogation for the sequentially eluted

The enantioselective synthesis of a series of C2 -symmetric 3,3'-diarylated 1,1'-spirobiindane-7,7'-diols (3,3'-diaryl-SPINOLs) was developed by sequential Rh-catalyzed twofold asymmetric conjugate arylation/BF3 -promoted diastereoselective spirocyclization (>20:1 d.r. and >99 % ee for all examples). Some phosphoramidite ligands were prepared from the 3,3'-Ph-SPINOL and applied to several catalytic asymmetric reactions, and the 3,3'-diarylated ligands showed higher enantioselectivities than the privileged nonsubstituted ligands.

High quality CdZnTe thick films were prepared on boron and gallium co-doped ZnO (BGZO) transparent conductive films by using close-spaced sublimation (CSS) method. Due to its high stability, hardness and similar thermal expansion coefficient with CdZnTe, BGZO films were also used to replace the traditional metal to form good ohmic contact with CdZnTe. CdZnTe thick film radiation detectors with BGZO/CdZnTe/BGZO structure were fabricated. The results showed a well response of the CdZnTe thick film detector (the energy resolution is about 25%) from a 60 KeV 241Am γ-source.

SnS:In thin films have been deposited on Mo substrates by chemical bath deposition method in acidic solution. The influences of different In-doped concentrations on the morphological, structural, optical properties and phase purities of SnS thin films have been investigated. Many sheet-like particles exist in the deposited SnS:In thin films. The doping of indium will decrease the thicknesses of the deposited thin films. The studies of photo-electrochemical (PEC) properties of SnS:In (In,10 at.%) thin films indicate that their PEC properties are enhanced by the annealing process. The fabrication of Pt/CdS/annealed SnS:In/Mo photocathode can further enhance the photo-current density to 0.790 mA·cm−2 at −0.4 V.

In this work, a novel highly sensitive electrochemical sensing platform has been developed for simultaneous determination of anticancer drugs doxorubicin (DOX) and dasatinib (DAS) by means of mesoporous Pd@Pt core–shell nanoparticles supported on MWCNT (Pd@Pt/MWCNT). The electrochemical behaviour of the drugs was assessed through cyclic voltammetry, while simultaneous determination was carried out using adsorptive stripping square wave voltammetry (AdSSWV). Under optimized conditions, the method exhibits linear responses towards simultaneous determination of DOX and DAS in the concentration ranges of 4.4–8580 nM and 38–9880 nM, with detection limits of 0.86 and 6.72 nM, respectively. Furthermore, the proposed platform was successfully used for reliable determination of DOX and DAS in urine and blood serum samples with good accuracy and precision. The satisfactory recoveries obtained in blood serum and urine samples showed the potential for application of the proposed platform in quality control in the pharmaceutical industry, clinical analysis and optimization of chemotherapeutic treatment. We found that the established sensor has several advantages in terms of high sensitivity and selectivity, ease of preparation, short analysis time, long-term stability and fast response.

Mechanical polishing treatment was carried out on polycrystalline CdZnTe thick films grown by close-spaced sublimation method. The influence of Al2O3 polishing powder particle sizes (2.5 μm, 1 μm and 0.05 μm) and polishing durations (1 h, 2 h and 3 h) on the structure, surface morphology and electrical performances of the CdZnTe thick films was studied by XRD, EDS, SEM, AFM and I-V characterization systems. The results showed that the reduction of the particle size of the polishing powder and the appropriate increase of the polishing time length could improve the surface roughness, surface defects and leakage current of the CdZnTe sample.

AlN ceramic substrates (c-AlN), with excellent thermal conductivity, were used to deposit high-quality polycrystalline CdZnTe (CZT) thick films for the first time. Meanwhile, AlN transition layers, made by magnetron sputtering method, have been introduced and annealed to modulate the interface properties of CZT/c-AlN composite structures for UV photodetectors. The relationship between the structure as well as performance of CZT films and the anneal temperature of AlN transition layers was studied by SEM, XRD, EDS, UV–vis spectra, XPS and current–voltage (I-V) characteristic. The CZT films deposited on the AlN transition layer annealed at 1200 °C have the best properties, with the full width at half maximum (FWHM) and leakage current of 0.163°and 2.15 × 10−9 A, respectively. The interface regulation can effectively promote the crystallinity of CZT films and lead to optimum UV detection performance of CZT/AlN composite structures.

BACKGROUND: Several species of Verbenaceae have been widely used in medicine, and some species of Verbenaceae have been observed good insecticidal activity, such as Lantana camara and Vitex negundo. There is no report about repellent activity of Clerodendrum bungei Steud. (C. bungei) against stored product insects. The chemical composition of C. bungei essential oil (EO) were identified, repellent activity of methanol extract, EO of C. bungei and two main components of EO against T. castaneum, L. serricorne and L. bostrychophila were evaluated for the first time. RESULTS: EO of C. bungei was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC–MS) and GC. A total of 25 components of the C. bungei EO were identified. The principal compounds in the EO were myristicin (75.0%), 2,2,7,7-Tetramethyltricyclo[6.2.1.0(1,6)]undec-4-en-3-one (4.1%) and linalool (3.4%). Results of bioassays indicated that C. bungei EO exerted strong repellent activity against three target insects. As main constituents, myristicin and linalool also had certain repellency. CONCLUSION: This work suggests that the EO of C. bungei has promising potential to develop into botanical repellents for the control of pest damage in warehouses and grain stores. GRAPHICAL ABSTRACT: [Image: see text]

The orientation of the disk of material accreting onto supermassive black holes that power quasars is one of most important quantities that are needed to understand quasars -- both individually and in the ensemble average. We present a hypothesis for determining comparatively edge-on orientation in a subset of quasars (both radio loud and radio quiet). If confirmed, this orientation indicator could be applicable to individual quasars without reference to radio or X-ray data and could identify some 10-20% of quasars as being more edge-on than average, based only on moderate resolution and signal-to-noise spectroscopy covering the CIV 1549A emission feature. We present a test of said hypothesis using X-ray observations and identify additional data that are needed to confirm this hypothesis and calibrate the metric., 7 pages, 2 figures, accepted for publication in ApJL

Galaxy mergers occur frequently in the early universe and bring multiple supermassive black holes (SMBHs) into the nucleus, where they may eventually coalesce. Identifying post-merger-scale (i.e., 2, but critical to constraining the progenitors of SMBH mergers. The redshift z~2 also marks the epoch of peak activity of luminous quasars, hence probing this spatial regime at high redshift is of particular significance in understanding the evolution of quasars. However, given stringent resolution requirements, there is currently no confirmed 2. Here we report two sub-arcsec double quasars at z>2 discovered from a targeted search with a novel astrometric technique, demonstrating a high success rate (~50%) in this systematic approach. These high-redshift double quasars could be the long-sought kpc-scale dual SMBHs, or sub-arcsec gravitationally-lensed quasar images. One of these double quasars (at z=2.95) was spatially resolved with optical spectroscopy, and slightly favors the scenario of a physical quasar pair with a projected separation of 3.5 kpc (0.46"). Follow-up observations of double quasars discovered by this targeted approach will be able to provide the first observational constraints on kpc-scale dual SMBHs at z>2., Comment: Published in Nature Astronomy (April 2021)

High-purity insoluble dietary fibre (HPIDF) was obtained from low-purity dietary fibre (LPDF) of Okara using a combined-enzyme method. For exploring the value of HPIDF as a functional food material, the structure, physicochemical properties, adsorption properties, potential bioactivities of HPIDF and their changes in different stages of digestion were explored in vitro. The results show that HPIDF shows a high perfect oil-holding capacity, higher viscosity, better cation exchange capacity, α-amylase activity ratio due to smaller particle size and larger specific surface area. The heavy metals-adsorption (Cd2+, Pb2+, Zn2+) shows the same, especially in simulated gastric fluid, which is similar to the adsorbability of glucose, cholesterol and acrylamide. Beyond the structure, the dissociation degree of some functional groups result from different digestive environments is the possible cause. Okara is an ideal material for the recovery of HPIDF, which has the potential to be processed into functional food materials.

We present spectroscopic measurements for 226 sources from the Gemini Near Infrared Spectrograph - Distant Quasar Survey (GNIRS-DQS). Being the largest uniform, homogeneous survey of its kind, it represents a flux-limited sample (mi . 19.0 mag, H . 16.5 mag) of Sloan Digital Sky Survey (SDSS) quasars at 1.5 . z . 3.5 with a monochromatic luminosity (λLλ) at 5100 ˚A in the range of 1044 − 1046 erg s−1 . A combination of the GNIRS and SDSS spectra covers principal quasar diagnostic features, chiefly the C iv λ1549, Mg ii λλ2798, 2803, Hβ λ4861, and [O iii] λλ4959, 5007 emission lines, in each source. The spectral inventory will be utilized primarily to develop prescriptions for obtaining more accurate and precise redshifts, black hole masses, and accretion rates for all quasars. Additionally, the measurements will facilitate an understanding of the dependence of rest-frame ultraviolet-optical spectral properties of quasars on redshift, luminosity, and Eddington ratio, and test whether the physical properties of the quasar central engine evolve over cosmic time., Facultad de Ciencias Astronómicas y Geofísicas, Instituto de Astrofísica de La Plata

We present the results of a pilot Hubble Space Telescope (HST) imaging study of the host galaxies of ten quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Probing more than an order of magnitude in BH and stellar masses, our sample is the first statistical sample to study the BH-host correlations beyond z>0.3 with reliable BH masses from reverberation mapping rather than from single-epoch spectroscopy. We perform image decomposition in two HST bands (UVIS-F606W and IR-F110W) to measure host colors and estimate stellar masses using empirical relations between broad-band colors and the mass-to-light ratio. The stellar masses of our targets are mostly dominated by a bulge component. The BH masses and stellar masses of our sample broadly follow the same correlations found for local RM AGN and quiescent bulge-dominant galaxies, with no strong evidence of evolution in the M_BH-M_*,bulge relation to z~0.6. We further compare the host light fraction from HST imaging decomposition to that estimated from spectral decomposition. We found a good correlation between the host fractions derived with both methods. However, the host fraction derived from spectral decomposition is systematically smaller than that from imaging decomposition by ~30%, indicating different systematics in both approaches. This study paves the way for upcoming more ambitious host galaxy studies of quasars with direct RM-based BH masses at high redshift., Comment: 19 pages, 8 figures, submitted to ApJ

Synthetic biology allows the re-engineering of biological systems and promotes the development of bioengineering to a whole new level, showing great potential in biomanufacturing. Here, in order to make the heterologous lycopene biosynthesis pathway compatible with the host strain YSy 200, we evolved YSy200 using a unique Synthetic Chromosome Rearrangement and Modification by LoxP-mediated Evolution (SCRaMbLE) system that is built in the Sc2.0 synthetic yeast. By inducing SCRaMbLE, we successfully identified a host strain YSy201 that can be served as a suitable host to maintain the heterologous lycopene biosynthesis pathway. Then, we optimized the lycopene biosynthesis pathway and further integrated into the rDNA arrays of YSy201 to increase its copy number. In combination with culturing condition optimization, we successfully screened out the final yeast strain YSy222, which showed a 129.5-fold increase of lycopene yield in comparison with its parental strain. Our work shows that, the strategy of combining the engineering efforts on both the lycopene biosynthesis pathway and the host strain can improve the compatibility between the heterologous pathway and the host strain, which can further effectively increase the yield of the target product.

The telemetry drill string transmits the measured drilling and formation parameters near the bit to the ground at high speed through the transmission line in the wired drill pipe and the inductive coupler formed by the coil embedded in the drill pipe joint. The voltage transfer function of the inductive coupler seriously affects the signal transmission characteristics of the telemetry drill string. Present research methods cannot accurately and quantitatively describe the influence of the electromagnetic parameters of the inductive coupler on its voltage transfer function. This paper quantitatively analyzes the effects of the electromagnetic parameters of the inductive coupler on signal transmission through reasonable high-frequency circuit modeling. The generation mechanism of eddy current in the magnetic core and the interaction mechanism between eddy current and coupling coils are studied using the electromagnetic detection analysis method of nondestructive testing (NDT) technology. Then, the high-frequency circuit model of the coupler containing eddy current loss is established. The mathematical model of input impedance and signal transmission characteristics of the inductive coupler is established through circuit analysis. The influence of the electromagnetic parameters of the magnetic core and the load resistance of the coupler on the voltage transmission characteristics and power transmission characteristics of the coupler is studied. The research results show that the relative permeability of the magnetic core, load resistance of the coupler, and signal frequency seriously affect the signal voltage transmission. When the relative permeability of the magnetic core material reaches 50, the voltage transmission of the inductive coupler is effectively improved. The electromagnetic simulation results are consistent with the theoretical analysis of the circuit model, which proves the correctness of the circuit model. This paper provides theoretical guidance for the electromagnetic design of inductive couplers and the improvement of signal transmission characteristics of telemetry drill string.

We report on continued, $\sim$15 year-long, broad Balmer emission lines in three metal-poor dwarf emission-line galaxies selected from Sloan Digital Sky Survey spectroscopy. The persistent luminosity of the broad Balmer emission indicates the galaxies are active galactic nuclei (AGNs) with virial black hole masses of $\sim 10^{6.7}{-10^{7.0}\ M_{\odot}}$. The lack of observed hard X-ray emission and the possibility that the Balmer emission could be due to a long-lived stellar transient motivated additional follow-up spectroscopy. We also identify a previously-unreported blueshifted narrow absorption line in the broad H$\alpha$ feature in one of the AGNs, indicating an AGN-driven outflow with hydrogen column densities of order $10^{17}$ cm$^{-2}$. We also extract light curves from the Catalina Real-Time Transient Survey and the Zwicky Transient Facility. We detect probable AGN-like variability in three galaxies, further supporting the AGN scenario. This also suggests the AGNs are not strongly obscured. This sample of galaxies are among the most metal-poor which host an AGN ($Z=0.05 - 0.16\ Z_\odot$). We speculate they may be analogues to seed black holes which formed in unevolved galaxies at high redshift. Given the rarity of metal-poor AGNs and small sample size available, we investigate prospects for their identification in future spectroscopic and photometric surveys., Comment: 8 pages, 4 figures, 1 table, 1 appendix; accepted for publication in MNRAS