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In this paper, lithium-doped ZnO films were precipitated on n-type Si (100) substrates by the sol-gel method. The crystal structure, surface morphology, and luminescence properties of the lithium-doped ZnO films were investigated. The results of the X-ray diffractometer (XRD) measurements show that the ZnO thin films with different lithium doping concentrations all have an obvious preferred orientation. According to the fitting result of photoluminescence (PL) spectra, we identify the existence of Li substitution for Zn acceptor defects and that the green emission peaks are caused by the dual effects of single ionized oxygen vacancy (V O •) to the valence band top and V O • to Li substitution for Zn acceptor transitions. From the PL spectra, no matter the number of spin-coated layers, there is a corresponding lithium doping ratio, which can make the Li substitution for Zn (Li Zn) acceptor defects concentration reach saturation. Under the same spin-coated layer, the visible luminescence intensity is significantly enhanced with an increase in lithium doping concentration. When the doping concentration reaches a certain value, the luminescence intensity reaches its maximum. Due to concentration quenching, a higher lithium doping ratio will result in a decrease in luminescence intensity. [ABSTRACT FROM AUTHOR]

In this report, Zn 1-x Cd x O ceramic thin films were deposited by the sol-gel method on an n-type Si (100) substrate. The structure, morphology, and luminescence properties of the thin films were studied. To elucidate the structure and the optical properties of Zn 1-x Cd x O thin films, our study focuses on the roles of changing the content of the doped Cd and the annealing temperature in Cd-doped ZnO thin films. The Cd doping behavior was investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and photoluminescence (PL). The research concentrates on the effects of doping concentration, annealing temperature, and isoelectronic trapping on the crystallization quality and luminescence properties of the thin films. On the basis of the different electronegativity of the doping elements, Cd substitution for Zn forms isoelectronic traps, which influence the intensity of luminescence and change the luminous peaks. By raising the annealing temperature further, the intensity of each diffraction peak of ZnO is gradually increasing, improving the quantity of Cd entering the ZnO crystal lattice. The PL spectra display that the ZnO thin films only appear in yellow-green emission bands, which appear redshift through the incorporation of Cd. With the increase in Cd doping amount, the yellow light luminous center keeps moving in the low energy direction. When the Cd doping amount reaches 20 %, the luminescence intensity reaches its maximum, which holds great promise for its application in light devices. [ABSTRACT FROM AUTHOR]

Nowadays, an effective and clean extinguishing agent or technology is highly desirable for lithium-ion battery (LIB) fires. Herein, the physicochemical properties and extinguishing effects of various extinguishing agents on 243 Ah lithium iron phosphate (LFP) battery fires are investigated systematically. The extinguishing mechanisms are deeply analyzed and the performance is comprehensively evaluated from the aspects of thermal runaway (TR) and toxicity suppression, cooling and extinguishing efficiency. Compared with HFC-227ea, C 6 F 12 O can absorb more heat through vaporization, thereby improving extinguishing and cooling efficiency. The lack of chemical inhibition effect and the tiny droplet size make water mist unable to suppress the high-temperature jet fire, but it has the lowest toxicity and highest cooling efficiency of 54.6%. F-500 and FireIce can improve the extinguishing performance of the water mist by encapsulating and taking hydrocarbon fuel away from the fire zone and inhibiting free radicals in the flame, respectively. 3% F-500 has the extinguishing efficiency of 78.4% and TR efficiency of 64.1%, while maintaining the cooling performance well. In the future, a novel type of fire-extinguishing agent with high heat capacity and latent heat, excellent extinguishing performance, high wettability, low toxicity and insulating properties is expected to be developed for LIB fires. [Display omitted] [ABSTRACT FROM AUTHOR]

Designing a robust bifunctional water splitting catalyst at low cost is of great importance for water splitting. Herein, the in situ-generated MoS2/NiS2 nanosheet heterostructures by cobalt incorporation on carbon paper (Co–MoS2/NiS2/CP) are first obtained by applying a scalable chemical vapor vulcanization approach. Based on the synergistic effects of cobalt element doping and the construction of MoS2/NiS2 heterostructures, the much enhanced electrocatalytic performance for full water electrolysis is clearly revealed. In particular, the electronic structure of MoS2/NiS2 heterostructures was further effectively modified by cobalt incorporation along with the electron density of catalytic sites, which both promote the Volmer step to speed up alkaline hydrogen evolution reaction (HER) and optimize the oxygen-containing intermediate adsorption to enhance oxygen evolution reaction (OER). Consequently, Co–MoS2/NiS2/CP heterostructures presented low overpotentials (HER: η10 = 109 mV; OER: η10 = 323 mV) in the basic solution. Furthermore, Co–MoS2/NiS2/CP was designed as a two-electrode alkaline electrolytic configuration for full water electrolysis. This strategy experimentally illustrates the feasibility of designing a conventional electrocatalyst for water electrolysis via the cooperative effects of metal doping and heterostructured engineering. [ABSTRACT FROM AUTHOR]

A novel concept—the contact-based landing on a mobile platform—is proposed in this paper. An adaptive backstepping controller is designed to deal with the unknown disturbances in the interactive process, and the contact-based landing mission is implemented under the hybrid force/motion control framework. A rotorcraft aerial vehicle system and a ground mobile platform are designed to conduct flight experiments, evaluating the feasibility of the proposed landing scheme and control strategy. To the best of our knowledge, this is the first time a rotorcraft unmanned aerial vehicle has been implemented to conduct a contact-based landing. To improve system autonomy in future applications, vision-based recognition and localization methods are studied, contributing to the detection of a partially occluded cooperative object or at a close range. The proposed recognition algorithms are tested on a ground platform and evaluated in several simulated scenarios, indicating the algorithm's effectiveness. [ABSTRACT FROM AUTHOR]

The finite-key security of the standard three-intensity decoy-state quantum key distribution (QKD) protocol in the presence of information leakage has been analyzed (Wang et al. in New J Phys 20:083027, 2018). On the other hand, the 1-decoy state QKD protocol has been proved to be able to achieve higher secret key rate than the three-intensity decoy-state QKD protocol in the finite-key regime by using only two different intensity settings (Davide et al. in Appl Phys Lett 112:171104, 2018). In this work, we analyze the finite-key security of the 1-decoy state QKD protocol with a leaky intensity modulator, which is used to generate the decoy state. In particular, we simulate the secret key rate under three practical cases of Trojan-horse attacks. Our simulation results demonstrate that the 1-decoy state QKD protocol can be secure over long distances within a reasonable time frame given that the intensity modulator is sufficiently isolated. By comparing the simulation results to those presented in Wang et al. (2018), we find that, as expected, the 1-decoy state QKD protocol is more robust against information leakage from the intensity modulator for all achievable distances. [ABSTRACT FROM AUTHOR]

SUMMARY: The aerial manipulator is a special and new type of flying robot composed of a rotorcraft unmanned aerial vehicle (UAV) and a/several manipulator/s. It has gained a lot of attention since its initial appearance in 2010. This is mainly because it enables traditional UAVs to conduct versatile manipulating tasks from air, considerably enriching their applications. In this survey, a complete and systematic review of related research on this topic is conducted. First, various types of structure designs of aerial manipulators are listed out. Subsequently, the modeling and control methods are introduced in detail from the perspective of two types of typical application cases: free-flight and motion-restricted operations. Finally, challenges for future research are presented. [ABSTRACT FROM AUTHOR]

In the context of functional time series, we propose a significance test to distinguish between short memory with a change point and long range dependence. The test is based on coefficients of projections onto an optimal direction that captures the dependence structure of the latent stationary functions that are not observable due to a potential change point. The optimal direction must be estimated as well. The test statistic is constructed using the local Whittle estimator applied to these coefficients. It has standard normal distribution under the null hypothesis (change point) and diverges to infinity under the alternative (long range dependence). The article includes asymptotic theory, a simulation study and an application to curve‐valued time series derived from intraday asset prices. [ABSTRACT FROM AUTHOR]

The finite-difference time domain (FDTD) method is widely used in ground–airborne transient electromagnetic modelling. Generally, this method offers great limitations because the calculation of the air layer is avoided and the surface assumption is flat. This study proposes a new method for ground–airborne 3D electromagnetic forward modelling that includes air layers and effectively solves the airborne TEM forward calculation of the coastal ocean and rugged terrains. The optimum selection of the air-layer resistivity and the identification ability of the long-wire source are discussed. By adding the pulse source signal to the control equation and realizing a direct calculation that includes the source, the cumbersome process of calculating the complex initial field is avoided. After establishing the mountain model and coastal ocean model, the electromagnetic response is discussed. Subsequently, the ground–airborne TEM modelling is subjected to a 3D numerical simulation of complex geological conditions. The validity of this method is verified by analytical solutions through a uniform half space. The results show that the method can achieve 3D and high-precision numerical calculations when it includes complex terrain and seawater. [ABSTRACT FROM AUTHOR]

The present study focuses on the photoluminescence (PL) properties of ZnO films prepared by the reaction of water and zinc. Temperature-dependent PL characteristics of the ZnO films have been investigated in the range from 15 to 260 K. The PL spectrum at 15 K is dominated by neutral donor-bound exciton (D0X) emissions. The emission line at about 3.304 eV can be due to the transition of free electrons to neutral acceptor states (eA0). It is suggested that the ultraviolet emission at room temperature can be attributed to the incorporation of eA0 and free exciton (FX) transitions, rather than sole FX. According to the temperature behavior of green band, it is further confirmed that the green emission is mainly related to the singly ionized oxygen vacancies. [ABSTRACT FROM AUTHOR]

• P in low-temperature combustion sludge ash (LTCA) is extracted by 0.8N HCl easily. • The ion exchange column method is suitable for purifying P-rich leachate. • As flow rate increased, the penetrable exchange capacity of Fe by CER decreased. • Thomas model can simulate adsorption characteristics of Fe in P-rich leachate by CER. • 84% total P in LTCA was recovered as struvite with low heavy metal concentration. As a phosphorus-rich material, low-temperature combustion sewage sludge ash (LTCA) contains over 9 wt% content of phosphorus (P) and a large proportion of impurities, especially the content of Fe arrives at 14.59 wt%. To fully utilize LTCA as a fertilizer, this study investigated a procedure for P recovery from LTCA via struvite crystallization with fewer impurities. The adsorption characteristics of P and Fe by cation exchange resin (CER) were explored by simulating using the macroscopic parametric equation Thomas model. Optimum purification conditions for P-rich leachate by cation exchange column method were determined. Results showed that approximately 97.21 wt% of P was extracted from LTCA at HCl concentration of 0.8 M and liquid/solid ratio of 20.0 ml/g. More than 90 wt% of impurities could be detached by making P-rich leachate flow through cation exchange bed filled by CER at 300 ml/h. The macroscopic parametric equation Thomas model could clearly describe the adsorption characteristics of Fe in P-rich leachate by CER. Theoretical basis for purification of high concentration Fe in P-rich leachate by CER was provided. Approximately 84.04 wt% of total P in LTCA was recovered as struvite crystal which had low concentrations of heavy metals (5.96 mg/kg for Cr, 45.21 mg/kg for Cu, 29.67 mg/kg for Ni, 2.24 mg/kg for Pb, and 290.6 mg/kg for Zn) and could be eco-friendly for agricultural application. X-ray diffraction and SEM-EDS analysis validated the formation of struvite. [ABSTRACT FROM AUTHOR]

Highlights • Low-temperature combustion enriches phosphorus in sludge better than incineration. • High O 2 concentration during low-temperature combustion promotes Ca-P generation. • Low-temperature combustion increases P-bioavailability in sludge bottom ash. • Phosphorus in sludge after low-temperature combustion is in form of orthophosphate. • Leaching of heavy metals in low-temperature combustion ash is reduced. Abstract The utilization of phosphorus from sewage sludge is an important method used to solve the shortage of phosphorus resources in the world. However, high levels of toxic compounds and low phosphorus bioavailability in sewage sludge are the main factors limiting its direct agricultural use. This paper proposes a low-temperature combustion method that can enrich the phosphorus in sludge ash. Low temperature-treated sewage sludge ash (LTSA) at different oxygen concentrations (20%, 60%, 100%) were obtained through a specific experimental device. Then, the species and leaching characteristics of phosphorus in LTSAs were analyzed and compared with pyrolysis sewage sludge char (PSSC) and incinerated sewage sludge ash (ISSA). Results show that low-temperature combustion of sludge increased the total phosphorus content in the bottom ash by 45.6%, and the bioavailable phosphorus content increased 2.9 times. Further, by increasing the concentration of oxygen while carrying out low-temperature combustion of sludge, part of the non-apatite inorganic P was converted to apatite P (AP), resulting in a 46.3% increase in AP in the sludge. Low-temperature combustion can also convert heavy metals (Cd, Cr, Cu, Pb, and Zn) in the sludge from an easily leachable form (acid extractable fraction and reducible fraction) to a stable form (reducible fraction) and decrease the leaching of heavy metals. Leaching of Cr and Cu decreased by 97.56% and 98.52%, respectively. [ABSTRACT FROM AUTHOR]

Ga nanoparticles and Ge nanostructures have been electrodeposited from 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIm]Tf 2 N) ionic liquid with pulsed laser assistance. Laser irradiation led to clustering and vertical growth of Ga nanospheres, and formation of Ge nanowires and branched nanowires. Ge nanowires were also electrodeposited on a Cu foil under laser irradiation. The as-prepared Ge nanowires film anode yielded an initial discharge and charge capacity of 1646 mAh/g and 1278 mAh/g, respectively, and retained nearly 70% of the original charge capacity after 50 cycles at 0.2 C. [ABSTRACT FROM AUTHOR]

The present work reports on the tunable optical emission from oxygen vacancies in ZnO nanorods. The common green luminescence at room temperature originated from oxygen vacancy defects can be mediated by simply controlling pH values of alkaline solutions without the introduction of any intentional dopants. The peak energies of the green band are found to be monotonously tuned in the range from 2.17 to 2.47 eV, which could promote the applications of tunable wavelength ZnO optoelectronic devices. The temperature dependent behavior of exciton transitions and oxygen vacancy recombinations in ZnO nanorods is investigated in detail. It is suggested that the localized bound exciton (LBX) attached near the lateral facets of ZnO nanorods could survive up to nearly room temperature due to the large binding energy. [ABSTRACT FROM AUTHOR]

Mesoporous nanoflakes Cu 2 S counter electrode (CE) was prepared from three-dimensional ordered macroporous (3-DOM) Cu film obtained by polystyrene microspheres assisted potentiostatic deposition for quantum dot-sensitized solar cell (QDSSC). The structrue of the Cu 2 S CE can be controlled by the size of polystyrene microspheres. The optimized Cu 2 S CE shows a charge transfer resistance (R CT ) as low as 1.24 Ω cm 2 , while the R CT of the Pt CE is 2250 Ω cm 2 . A CdSe QDSSC based on the mesoporous nanoflakes Cu 2 S CE achieved a power conversion efficiency of 6.01%, which was higher than that based on Pt CE (1.74%) and ordinary Cu 2 S CE (4.85%). This enhancement can be attributed to the increased surface area, the easy electrolyte diffution and the improved electron transport of mesoporous nanoflakes Cu 2 S CE. This work provides a new effective approach for the structure control of Cu 2 S CE for high-efficiency QDSSC. [ABSTRACT FROM AUTHOR]

The effect of a pulsed laser on the electrodeposition of germanium on indium tin oxide glass in the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIm]Tf 2 N) was investigated. Cyclic voltammetric analysis of GeCl 4 in [EMIm]Tf 2 N showed that laser irradiation produced a positive shift of the reduction potential and an increase in the reduction current. Laser irradiation influenced the morphology and crystallinity of the Ge deposits. A deposition time of 1200 s gave rise to amorphous Ge deposits when laser irradiation was not applied, whereas laser irradiation led to a polycrystalline branched structure. The length and width of the branched structures were about 9.58 and 2.18 μm, respectively, and the average grain size of the sample was ∼76 nm. The morphology and size of the Ge deposits could be controlled by adjusting the deposition time under laser irradiation. The mechanism of growth of the Ge deposits under laser irradiation was discussed in detail. [ABSTRACT FROM AUTHOR]

[Display omitted] • Accurate quantification of soil erosion sub-process by remote sensing and check dam. • Vegetation restoration significantly reduced soil erosion modulus. • Check dams effectively reduce sediment delivery on the watershed scale. • The variation of erosion and deposition changes the sediment delivery ratio. China has implemented a series of ambitious soil and water conservation (SWC) projects on the Chinese Loess Plateau, which have significantly changed the erosion, transport, and deposition of sediment. As a result, the sediment flux of the Yellow River, once the largest carrier of fluvial sediment worldwide, has been reduced by approximately 85 % in the past 60 years. However, the effects of SWC measures on erosion, transport, and deposition of sediment are still difficult to quantify, which greatly limits the further planning and adjustment of SWC measures. Here, we determined soil erosion, sediment deposition, and sediment yield at different historical stages in a 187 km2 hilly and gully watershed on the Chinese Loess Plateau using the unmanned aerial vehicle (UAV) photogrammetry technology combined with check dam surveying and hydrologic monitoring. The results show that the construction of check dams and vegetation restoration significantly reduced the soil erosion rate, from 21,144 t km−2 yr−1 at Stage-1 (1960–1969) to 13,819 ± 3,622 t km−2 yr−1 at Stage-2 (1970–1999) and further to 4,723 ± 1,278 t km−2 yr−1 at Stage-3 (2000–2018). The sediment deposition rate was estimated to be 5,989 and 2,582 ± 351 t km−2 yr−1 at Stage-2 and Stage-3, respectively. The variation in the erosion and deposition of sediment led to a significant change in the sediment delivery ratio, from 1 at Stage-1 to 0.57 at Stage-2 and 0.45 at Stage-3. Our research results provide an important reference for further SWC planning. [ABSTRACT FROM AUTHOR]

Bright green luminescence is achieved from undoped ZnO films prepared by the reaction of oxygen and zinc powder. The green emission band is considered to be mainly due to the singly ionized oxygen vacancies. Temperature dependence of exciton transitions in the undoped ZnO films has been investigated in the range from 10 to 270 K. The PL spectrum at 10 K is dominated by neutral donor-bound exciton (D°X) emissions. The dominant emission centered at about 3.303 eV at above 45 K can be attributed to the localized bound exciton (LBX) transitions related to basal plane stacking faults. LBX transitions can survive up to near room temperature due to the LBX binding energy of 68 meV. [ABSTRACT FROM AUTHOR]

• A UAV-based method estimating sediment deposited behind check dams was developed. • Errors of the optimal model for single and regional check dams are 12–13% and 2–3%. • This method avoids limitations of tedious field surveys and historical records. • This method can evaluate sediment retained by check dams in areas as large as 211,800 km2. The estimation of sediment deposited behind dams and reservoirs is of great significance for quantifying soil erosion rate and sediment flux. However, existing methods of sediment volume estimation often require detailed field measurements and historical topographic data, limiting the broader application of these methods. In this paper, focusing on the region that suffers the world's most severe soil erosion, we combine unmanned aerial vehicle (UAV) photogrammetry and simulate submerging analysis to propose a novel method for estimating sediment silted by check dams under complex topography. We obtained 1339 groups of topographic factors and ascertained the corresponding volumes of sediment deposited behind check dams in the loess hilly region of China (LHRC), and established five different models combined with regression analysis. Two different sets of data were used for method validation and optimal model determination. The results showed that the error of the optimal model in the volume estimation of single check dam and regional check dams is 12–13% and 2–3%, respectively. Additionally, the area-volume model has the potential to evaluate the sediment retention capacity of check dams (in the order of billions of cubic meters) in the whole LHRC, because the variables are easy to obtain and the model accuracy is relatively high. The further application of this method will help to evaluate the watershed sediment yield and regional soil and water conservation benefits, and is of great significance for explaining the future changes in water and sediment in the Yellow River basin. [ABSTRACT FROM AUTHOR]

The growth of Li1+xMn2O4 via detonation reaction was investigated with respect to the presence of energetic precursors, such as the metallic nitrates and the degree of confinement of the explosive charge. The detonation products were characterized by scanning electron microscopy. Powder X-ray diffraction and transmission electron microscopy were used to characterize the products. Li1+xMn2O4 with 1 ∼ 2μm spherical morphology and more uniform secondary particles, but with smaller primary particles of diameters from 20 to 60 nm and a variety of morphologies were found. The oxides produced by this cheap method affirmed the validity of detonation synthesis of nano-size powders. [ABSTRACT FROM AUTHOR]

Nanoproducts spherical spinel lithium manganese oxide (LiMnO) with about 20 nm in diameter was synthesized by explosive method. The growth of lithium manganate via detonation reaction was investigated with respect to the presence of an energetic precursor, such as the metallic nitrate and the degree of confinement of the explosive charge. The detonation products were characterized by scanning electron microscopy. Powder X-ray diffraction and transmission electron microscopy were used to characterize the products. Lithium manganate with spherical morphology and more uniform secondary particles, with smaller primary particles of diameters from 10 to 30 nm and a variety of morphologies were found. Lithium manganate with a fine spherical morphology different from that of the normal spinel is formed after detonation wave treatment due to the very high quenching rate. It might also provide a cheap large-scale synthesis method. Explosive detonation is strongly nonequilibrium processes, generating a short duration of high pressure and high temperature. Free metal atoms are first released with the decomposition of explosives, and then theses metal and oxygen atoms are rearranged, coagulated and finally crystallized into lithium manganate during the expansion of detonation process. [ABSTRACT FROM AUTHOR]

Abstract: Spinel lithium titanate nanoparticles have been synthesized using anatase and brookite nanocrystallites, as precursors. The corresponding products, A- and B-Li4Ti5O12 nanoparticles, have distinct differences in the optical absorption property, electrochemical performance and photocatalytic activity. The UV–vis absorption spectrum of B-Li4Ti5O12 nanoparticles shows strong and wide absorption in the ultraviolet and visible region. B-Li4Ti5O12 nanoparticles from brookite exhibit a higher discharge capacity than A-Li4Ti5O12 from anatase. The charge–discharge cycle stability for two types of Li4Ti5O12 nanoparticles is excellent. Besides, B-Li4Ti5O12 nanoparticles have much higher photocatalytic activity in the degradation of pollutant CHCl3 than A-Li4Ti5O12. [Copyright &y& Elsevier]

Abstract: In this work, we fabricated quantum dots light-emitting devices with hole-injection layer, molybdenum oxide (MoO3) substituting for poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) which is hygroscopic and acidic and, therefore, a source of interface instability. A significant enhancement in luminance and current efficiency in MoO3-containing devices was observed. In addition, MoO3-containing devices were more stable in the air than those with PEDOT:PSS as the hole injection layer. The hole injection and transport of the devices were studied by the J–V characteristics of the hole-only devices. The excellent performance of the devices was principally a result of MoO3 possessing lower injection barrier for the hole and better stability than PEDOT:PSS. [Copyright &y& Elsevier]

Abstract: We demonstrated the enhancement of electron transfer from CdSe/ZnS core/shell quantum dots (QDs) to TiO2 films via thermal annealing by means of steady-state and time-resolved photoluminescence (PL) spectroscopy. The significant decrease in PL intensities and lifetimes of the QDs on TiO2 films was clearly observed after thermal annealing at temperature ranging from 100°C to 300°C. The obtained rates of electron transfer from CdSe core/shell QDs with red, yellow, and green emissions to TiO2 films were significantly enhanced from several times to an order of magnitude (from ∼107 s−1 to ∼108 s−1). The improvement in efficiencies of electron transfer in the TiO2/CdSe QD systems was also confirmed. The enhancement could be considered to result from the thermal annealing reduced distance between CdSe QDs and TiO2 films. The experimental results revealed that thermal annealing would play an important role on improving performances of QD based optoelectronic devices. [Copyright &y& Elsevier]

Herein, a monolithic micro-pixelated light-emitting diode (μLED) display realized using ion-surface-treatment-based planar-geometry pixelation is reported. A high-resolution blue-emitting μLED array is fabricated by optimizing ion species of a near-surface selectively positioned isolation process. The μLED array exhibiting inhibited surface recombination and higher output power is achieved by using heavy ions, such as fluorine (F−), due to more stable opto-electrical isolation and better process reliability. Furthermore, the low forward voltage of F−-IST-based μLED pixels can effectively improve the wall-plug efficiency for the μLED array with a pixel diameter of 6 μm. Conversely, the poor thermal stability of light hydrogen (H+) ions limits its device applications. Analysis based on a rate equation model reveals that the luminescence mechanism of F−-IST-based μLEDs is dominated by radiative recombination, which will benefit the planar-geometry pixelation for realizing highly efficient full-color microdisplays. [ABSTRACT FROM AUTHOR]

Abstract: Optical properties of Mn-doped Zn x Cd1− x S nanocrystals were studied by steady-state and time-resolved photoluminescence (PL) spectroscopy. The doped nanocrystals with PL quantum yield up to 29% were synthesized by growing a thin ZnS layer on the MnS core and then growing a CdS layer with different thicknesses using nucleation-doping strategy. The absorption band edge of Zn x Cd1− x S nanocrystals was tuned from 425 to 475nm by growing the CdS layer with various thicknesses under different Zn/Cd molar ratios to vary the composition. The PL band of Mn-doped nanocrystals was found to originate from emissions of Mn2+ ions and defect states. [Copyright &y& Elsevier]

Abstract: Mössbauer spectroscopy is used to characterize the crystallite size and structure of CoFe2− x Y x O4 (x=0, 0.1, 0.3, 0.5) ferrite nanocrystallites synthesized by the sol–gel auto-combustion method. The effect of the substitution of Fe3+ ions by Y3+ ions on the structure of cobalt ferrite nanocrystallites is investigated. The Mössbauer spectra showed two sets of six-line hyperfine patterns for all the samples, indicating the presence of Fe in both A and B-sites. On increasing the concentration of doped Y, the hyperfine field strength and the isomer shift first increase and then decrease, whereas the quadrupole splitting continuously increases. The superparamagnetism was observed for all the samples and the change of ratio of the superparamagnetism component reflects the size of crystal grain. [Copyright &y& Elsevier]

Existing NR-IIQA (no reference-based inpainted image quality assessment) algorithms assess the quality of an inpainted image via artificially designed unnaturalness expression, which often fail to capture inpainted artifacts. This paper presents a new deep rank learning-based method for NR-IIQA. The model adopts a siamese deep architecture, which takes a pair of inpainted images as input and outputs their rank order. Each branch utilizes a CNN structure to capture the global structure coherence and a patch-wise coherence assessment module (PCAM) to depict the local color and texture consistency in an inpainted image. To train the deep model, we construct a new dataset, which contains thousands of pairs of inpainted images with ground-truth quality ranking labels. Rich ablation studies are conducted to verify the key modules of the proposed architecture. Comparative experimental results demonstrate that our method outperforms existing NR-IIQA metrics in evaluating both inpainted images and inpainting algorithms. • Siamese CNN-based NR-IIQA, automatically ranking two inpainted images. • A patch-wise coherence assessment module to evaluate local color and texture consistency within and around inpainted contents. • A dataset containing thousands of inpainted image pairs with ground-truth ranking labels. [ABSTRACT FROM AUTHOR]

Direct genomic manipulation at a specific locus is still not feasible in most vertebrate model organisms. In vertebrate cell lines, genomic lesions at a specific site have been introduced using zinc-finger nucleases (ZFNs). Here we adapt this technology to create targeted mutations in the zebrafish germ line. ZFNs were engineered that recognize sequences in the zebrafish ortholog of the vascular endothelial growth factor-2 receptor, kdr (also known as kdra). Co-injection of mRNAs encoding these ZFNs into one-cell-stage zebrafish embryos led to mutagenic lesions at the target site that were transmitted through the germ line with high frequency. The use of engineered ZFNs to introduce heritable mutations into a genome obviates the need for embryonic stem cell lines and should be applicable to most animal species for which early-stage embryos are easily accessible. [ABSTRACT FROM AUTHOR]

Abstract: ZnO films with strong c-axis-preferred orientation have been prepared by a single source chemical vapor deposition technique using zinc acetate as source material at the growth temperature of 230°C. The strong UV and blue emissions were observed in the photoluminescence spectra of as-grown films. A small quantity of residual zinc acetate was reserved on the surface of as-grown ZnO films and the emission mechanism of blue luminescence was nearly related to the CH3COO– of unidentate type. The blue emission disappeared and the green emission appeared after annealing treatment. The green emission is related to the singly ionized oxygen vacancies. [Copyright &y& Elsevier]

Abstract: Potassium titanate nanowires have been synthesized by a hydrothermal method using anatase and brookite nanocrystallites, respectively, as precursors. The corresponding products, alpha- and beta-K2Ti6O13 nanowires, have distinct differences in structure and properties. Under the same conditions, the amount of K intercalated into anatase TiO2 is larger than that into brookite TiO2. The multiple types of reserved short Ti–O bonds in beta-K2Ti6O13 confined the growth of nanowires along the [010] orientation and made the beta-K2Ti6O13 nanowires stubby. The UV–vis absorption spectrum of beta-K2Ti6O13 nanowires showed strong and wide absorption in the ultraviolet and visible region. Beta-K2Ti6O13 is thermodynamically more stable than alpha-K2Ti6O13. [Copyright &y& Elsevier]

Abstract: Highly orientated ZnO thin films and the self-organized ZnO nanorods can be easily prepared by a simple chemical vapor deposition method using zinc acetate as a source material at the growth temperature of 180 and 320°C, respectively. The ZnO thin films deposited on Si (100) substrate have good crystallite quality with the thickness of 490nm after annealing in oxygen at 800°C. The ZnO nanorods grown along the [0001] direction have average diameter of 40nm with length up to 700nm. The growth mechanism for ZnO nanorods can be explained by a vapor–solid (VS) mechanism. Photoluminescence (PL) properties of ZnO thin films and self-organized nanorods were investigated. The luminescence mechanism for green band emission was attributed to oxygen vacancies and the surface states related to oxygen vacancy played a significant role in PL spectra of ZnO nanorods. [Copyright &y& Elsevier]

The DNA-binding specificities of transcription factors can be used to computationally predict cis-regulatory modules (CRMs) that regulate gene expression. However, the absence of specificity data for the majority of transcription factors limits the widespread implementation of this approach. We have developed a bacterial one-hybrid system that provides a simple and rapid method to determine the DNA-binding specificity of a transcription factor. Using this technology, we successfully determined the DNA-binding specificity of seven previously characterized transcription factors and one novel transcription factor, the Drosophila melanogaster factor Odd-skipped. Regulatory targets of Odd-skipped were successfully predicted using this information, demonstrating that the data produced by the bacterial one-hybrid system are relevant to in vivo function. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the neuroprotective effects of naringin on the memory impairment of hydrocortisone mice, and to elucidate the potential underlying molecular mechanisms. In the present study, a hydrocortisone model was constructed. Novel object recognition, Morris water maze and step-down tests were performed in order to assess the learning and memory abilities of mice. Hematoxylin and eosin staining was used to observe pathological changes in the hippocampus and hypothalamus. Transmission electron microscopy was used to observe the ultrastructural changes in the hippocampus. Immunohistochemistry was used to detect the expression of ERα and ERβ. Western blotting was performed to detect the expression of each protein in the relevant system. It was found that naringin can significantly improve cognitive, learning and memory dysfunction in mice with hydrocortisone memory impairment. In addition, naringin can exert neuroprotective effects through a variety of mechanisms, including amyloid β metabolism, Tau protein hyperphosphorylation, acetylcholinergic system, glutamate receptor system, oxidative stress and cell apoptosis. Naringin can also affect the expression of phosphorylated-P38/P38, indicating that the neuroprotective effect of naringin may also involve the MAPK/P38 pathway. The results of the present study concluded that naringin can effectively improve the cognitive abilities of mice with memory impairment and exert neuroprotective effects. Thus, naringin may be a promising target drug candidate for the treatment of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

[Display omitted] • MOF-derived porous xPd-NPs@ZIF-8/ZnO were prepared by optimized heat treatment. • Ultrafast high response properties of the sensors were achieved under UV excitation. • Coupling effects of photoexcitation and thermal excitation were explored in detail. • The sensing mechanism of the superior performances were systematically studied. Metal-organic frameworks (MOFs) have been regarded as a potential candidate with great application prospects in the field of gas sensing. Although plenty of previous efforts have been made to improve the sensitivity of MOF-based nanocomposites, it is still a great challenge to realize ultrafast and high selectivity to typical flammable gases in a wide range. Herein, porous xPd-NPs@ZnO were prepared by optimized heat treatment, which maintained the controllable morphology and high specific surface area of 471.08 m2g−1. The coupling effects of photoexcitation and thermal excitation on the gas-sensing properties of nanocomposites were systematically studied. An ultrafast high response of 88.37 % towards 200 ppm H 2 was realized within 1.2 s by 5.0Pd-NPs@ZnO under UV photoexcitation. All xPd-NPs@ZnO exhibited favorable linearity over an extremely wide range (0.2–4000 ppm H 2) of experimental tests, indicating the great potential in quantitative detection. The photoexcited carriers enabled the nanocomposites a considerable response at lower operating temperatures, which made diverse applications of the sensors. The mechanisms of high sensing performances and the photoexcitation enhancement were systematically explained by DFT calculations. This work provides a solid experimental foundation and theoretical basis for the design of controllable porous materials and novel photoexcited gas detection. [ABSTRACT FROM AUTHOR]

To enhance aerial image detection in complex environments characterized by multiple small targets and mutual occlusion, we propose an aerial target detection algorithm based on an improved version of YOLOv5 in this paper. Firstly, we employ an improved Mosaic algorithm to address redundant boundaries arising from varying image scales and to augment the training sample size, thereby enhancing detection accuracy. Secondly, we integrate the constructed hybrid attention module into the backbone network to enhance the model's capability in extracting pertinent feature information. Subsequently, we incorporate feature fusion layer 7 and P2 fusion into the neck network, leading to a notable enhancement in the model's capability to detect small targets. Finally, we replace the original PAN + FPN network structure with the optimized BiFPN (Bidirectional Feature Pyramid Network) to enable the model to preserve deeper semantic information, thereby enhancing detection capabilities for dense objects. Experimental results indicate a substantial improvement in both the detection accuracy and speed of the enhanced algorithm compared to its original version. It is noteworthy that the enhanced algorithm exhibits a markedly improved detection performance for aerial images, particularly under real-time conditions. [ABSTRACT FROM AUTHOR]

Herein, a novel molecular SO2‐Bri‐DSB based on the sulfone‐bridged distyrylbenzene derivative is synthesized, and its organic crystal is fabricated. It has a very high photoluminescence (PL) quantum efficiency in the solution and crystalline state, i.e., dual‐state emission (DSE), and the corresponding PL mechanism is clarified in detail using the transient absorption and transient PL test. The PL behaviors in the monomolecular state and organic crystal are compared. In addition, the optical anisotropy of the SO2‐Bri‐DSB crystal is thoroughly investigated using various polarization‐dependent spectroscopy techniques. The time evolution of anisotropy is composed of a step behavior caused by the anisotropy of the electronic transition and a slow enhancing process with a lifetime of 4.86 ns, which is governed by the change in emission lifetime due to the anisotropy. The space‐resolved evolution of the optical anisotropy is investigated using the polarization‐dependent light wave‐guiding test and exhibits that the emission anisotropy gradually decreases with length, and it has a longer effective propagation length than the polarization emission signal. The findings provide insight into the intrinsic optical anisotropy of single‐molecular crystals and indicate that these materials have enormous potential in the domains of polarization lighting and display. [ABSTRACT FROM AUTHOR]

In 2 Mo 3 O 12 is considered to be a positive thermal expansion (PTE) material at room temperature since its negative thermal expansion (NTE) response temperature range is above 343 °C. With the expectation of tuning the NTE performance of In 2 Mo 3 O 12 , a series of In 2 Mo 3-x W x O 12 solid solutions was synthesized via B-site replacement by W6+. The effects of W6+ substitution on the phase composition, morphology, phase transition temperature (T pt) and thermal expansion behavior of In 2 Mo 3-x W x O 12 were systematically investigated. Results indicate that the replacement of Mo6+ by W6+ does not induce a change in the crystal structure of parent phase In 2 Mo 3 O 12 and can form continuous solid solutions of In 2 Mo 3-x W x O 12. With increasing composition parameter x, the T pt of In 2 Mo 3-x W x O 12 decreases, the corresponding NTE response temperature range is widened and NTE performance is improved. The coefficient of thermal expansion (CTE) of In 2 Mo 3-x W x O 12 becomes more negative. As expected, the T pt of In 2 Mo 3-x W x O 12 is tunable by adjusting the composition parameter x, and the tuning mechanism of NTE performance is discussed from the prospect of crystal structure. [ABSTRACT FROM AUTHOR]

Background: Postoperative hypoxemia in acute type A aortic dissection (AADA) is a common complication and is associated with negative outcomes. This study aimed to analyze the efficacy of low-dose (5-10 ppm) inhaled nitric oxide (iNO) in the management of hypoxemia after AADA surgery.Methods: In this retrospective observational study, Medical records of patients who underwent AADA surgery at two institutions between January 2015 and January 2018 were collected. Patients with postoperative hypoxemia were classified as iNO and control groups. Clinical characteristics and outcomes were compared using a propensity score-matched (PSM) analysis.Results: Among 436 patients who underwent surgical repair, 187 (42.9%) had hypoxemia and 43 were treated with low-dose iNO. After PSM, patients were included in the iNO treatment (n = 40) and PSM control (n = 94) groups in a 1:3 ratio. iNO ameliorated hypoxemia at 6, 24, 48, and 72 h after initiation, and shortened the durations of ventilator support (39.0 h (31.3-47.8) vs. 69.0 h (47.8-110.3), p < 0.001) and ICU stay (122.0 h (80.8-155.0) vs 179.5 h (114.0-258.0), p < 0.001). There were no significant between-group differences in mortality, complications, or length of hospital stay.Conclusions: In this study, we found that low-dose iNO improved oxygenation in patients with hypoxemia after AADA surgery and shortened the durations of mechanical ventilation and ICU stay. No significant side effects or increase in postoperative mortality or morbidities were observed with iNO treatment. These findings warrant a randomized multicenter controlled trial to assess the exact efficiency of iNO for hypoxemia after AADA. [ABSTRACT FROM AUTHOR]

With the construction of a new-type power system under the China "double carbon" target and the increasing diversification of the energy demand on the user side, the short-term load forecasting of the power system is facing new challenges. To fully exploit the massive information contained in data, based on the graph convolutional network (GCN) and long short-term memory network (LSTM), this paper presents a new short-term load forecasting method for power systems considering multiple factors. The Spearman rank correlation coefficient was used to analyse the correlation between load and meteorological factors, and a model including meteorology, dates, and regions was established. Secondly, GCN and LSTM are jointly used to extract the spatial and temporal characteristics of massive data, respectively, and finally achieve short-term power load prediction. Historical electrical load data from 2020 to 2022 public data of a real industrial park in southern China were selected to verify the validity of the proposed method from the aspects of forecasting accuracy, feature dimension, and training time. [ABSTRACT FROM AUTHOR]

Currently, it is significant to study the fire suppression of battery modules in energy storage stations. In this work, the combustion tests of a single cell and battery module were conducted on the 243 Ah lithium iron phosphate battery. Meanwhile, the fire extinguishing effect of C6F12O on large-scale battery module fire was verified under a real-scale fire scenario. Results show that the thermal runaway process of a single cell can be divided into four stages. The thermal runaway process had an "incubation period" in stage II, which was suitable for early warning and fire extinguishing. Thermal runaway can propagate within the battery body and the thermal runaway propagation time was 121 s. Thermal runaway propagation can occur in the battery module, which is much more aggressive and risky than a single cell. It needed around 50 kJ to 60 kJ to support the thermal runaway propagation between an adjacent cell in the battery module. Furthermore, The C6F12O has good fire extinguishing and cooling effect, which can successfully inhibit the thermal runaway propagation in the battery module. Meanwhile, when the designed fire extinguishing concentration of C6F12O is reached in the battery pack, the subsequent battery will not be ignited even if the safety valve is opened. [ABSTRACT FROM AUTHOR]

Orthorhombic Sc 2 (MoO 4) 3 nanofibers have been prepared by ethylene glycol assisted electrospinning method. The effects of annealing temperature, precursor concentration, spinning distance and solvent on the preparation of Sc 2 (MoO 4) 3 nanofibers were characterized by XRD, SEM, HRTEM, EDX and high-temperature XRD. XRD analysis shows as-prepared nanofibers are amorphous. Orthorhombic Sc 2 (MoO 4) 3 nanofibers can be fabricated after annealing at different temperatures in 500–800 °C for 2 h. The crystallinity of Sc 2 (MoO 4) 3 nanofibers improves and the nanofiber diameter decreases gradually as the annealing temperature increases. However, the nanofiber structure was destroyed at the annealing temperature above 700 °C. Higher precursor concentration results in a slight increase of diameter and decrease in destroying temperature of Sc 2 (MoO 4) 3 nanofibers. Spinning distance also affects the diameter of nanofibers, and the nanofiber diameter decreases as the distance increases. One-dimensional orthorhombic Sc 2 (MoO 4) 3 nanofibers exhibit anisotropic negative thermal expansion. In 25–700 °C, the coefficients of thermal expansion (CTE) of α a , α b and α c are −5.81 × 10−6 °C−1, 4.80 × 10−6 °C−1 and -4.33 × 10−6 °C−1, and the α l of Sc 2 (MoO 4) 3 nanofibers is −1.83 × 10−6 °C−1. [ABSTRACT FROM AUTHOR]

In this work, Sc 2 Mo 3 O 12 has been synthesized via one-pot hydrothermal reaction. The effects of process conditions on the crystal structure, morphology, photocatalytic activity and negative thermal expansion (NTE) behaviors of flower-like Sc 2 Mo 3 O 12 were systematically investigated. Results indicate that orthorhombic flower-like Sc 2 Mo 3 O 12 assembled by nano-size flaky crystal grains can be synthesized by one-pot hydrothermal reaction at a temperature as low as 120 °C for 2 h. The hydrothermal reaction temperature and time have no obvious effects on the crystal structure and morphology. However, the photocatalytic property of synthesized Sc 2 Mo 3 O 12 is sensitive to the above parameters. The sample synthesized at 200 °C for 2 h shows the best photocatalytic degradation of methyl orange, and the degradation rate is 73.32% in 2 h 1The coefficient of thermal expansion (CTE) of Sc 2 Mo 3 O 12 is −1.99 × 10−6 °C−1 in 50–500 °C tested using TMA. The high-temperature XRD analysis reveals that Sc 2 Mo 3 O 12 exhibits anisotropic NTE and the intrinsic CTE is measured to be −2.09 × 10−6 °C−1 in 25–800 °C. [ABSTRACT FROM AUTHOR]

The variational quantum algorithm (VQA) is a hybrid classical–quantum algorithm. It can actually run in an intermediate-scale quantum device where the number of available qubits is too limited to perform quantum error correction, so it is one of the most promising quantum algorithms in the noisy intermediate-scale quantum era. In this paper, two ideas for solving the learning with errors problem (LWE) using VQA are proposed. First, after reducing the LWE problem into the bounded distance decoding problem, the quantum approximation optimization algorithm (QAOA) is introduced to improve classical methods. Second, after the LWE problem is reduced into the unique shortest vector problem, the variational quantum eigensolver (VQE) is used to solve it, and the number of qubits required is calculated in detail. Small-scale experiments are carried out for the two LWE variational quantum algorithms, and the experiments show that VQA improves the quality of the classical solutions. [ABSTRACT FROM AUTHOR]

A correction to the article "Identification of Chromosome Sequence Motifs That Mediate Meiotic Pairing and Synapsis in C. Elegans" by Carolyn M. Phillips, Xiangdong Meng, and Lei Zhang.

In this paper, we consider the optimization of the quantum circuit for discrete logarithm of binary elliptic curves under a constrained connectivity, focusing on the resource expenditure and the optimal design for quantum operations such as the addition, binary shift, multiplication, squaring, inversion, and division included in the point addition on binary elliptic curves. Based on the space-efficient quantum Karatsuba multiplication, the number of CNOTs in the circuits of inversion and division has been reduced with the help of the Steiner tree problem reduction. The optimized size of the CNOTs is related to the minimum degree of the connected graph. [ABSTRACT FROM AUTHOR]

Although coronary artery recanalization after myocardial infarction improves patient outcomes, inadequate ventricular remodeling following ischemia-reperfusion (IR) injury and secondary cardiac fibrosis (CF) are common and can lead to heart failure. MicroRNAs (miRNAs) play an important role in cardiovascular disorders. However, the underlying molecular mechanism of miRNAs in the occurrence and progression of CF has not been fully elucidated. Herein, through the construction of an I/R rat model and an angiotensin II-induced CF cell model, we evaluated the role of miR-375-3p in the progression of CF. In the I/R rat model and CF cell model, miR-375-3p promoted fibrosis by accelerating the ferroptosis of cardiomyocytes through mediating glutathione peroxidase 4 (GPX4). Furthermore, we treated the rats or cell model with miR-375-3p antagomir (or inhibitor) and ferroptosis inhibitor Ferrostatin-1 (Fer-1). The results showed that miR-375-3p antagomir (or inhibitor) and Fer-1 promoted the antioxidant capacity of cardiac fibroblasts, reduced GPX4-mediated ferroptosis process and alleviated I/R-induced CF. In conclusion, this study revealed that miR-375-3p directly targeted GPX4—an inhibitor of the ferroptosis pathway. Meanwhile, miR-375-3p can be a new potential biomarker for the prevention and treatment of CF. [ABSTRACT FROM AUTHOR]

Hydrogen and renewable electricity-based microgrid is considered to be a promising way to reduce carbon emissions, promote the consumption of renewable energies and improve the sustainability of the energy system. In view of the fact that the existing day-ahead optimal operation model ignores the uncertainties and fluctuations of renewable energies and loads, a two-stage energy management model is proposed for the sustainable wind-PV-hydrogen-storage microgrid based on receding horizon optimization to eliminate the adverse effects of their uncertainties and fluctuations. In the first stage, the day-ahead optimization is performed based on the predicted outpower of WT and PV, the predicted demands of power and hydrogen loads. In the second stage, the intra-day optimization is performed based on the actual data to trace the day-ahead operation schemes. Since the intra-day optimization can update the operation scheme based on the latest data of renewable energies and loads, the proposed two-stage management model is effective in eliminating the uncertain factors and maintaining the stability of the whole system. Simulations show that the proposed two-stage energy management model is robust and effective in coordinating the operation of the wind-PV-hydrogen-storage microgrid and eliminating the uncertainties and fluctuations of WT, PV and loads. In addition, the battery storage can reduce the operation cost, alleviate the fluctuations of the exchanged power with the power grid and improve the performance of the energy management model. [ABSTRACT FROM AUTHOR]

• The internal temperature of the cell was measured to study the temperature rebound. • The cooling effect of intermittent spray with different periods and duty cycles were studied. • The gas toxicity of LIBs under a different SOC and water spray was evaluated. The fire extinguishing and cooling of lithium-ion battery thermal runaway have attracted significant research attention. In this study, an intermittent spray method for cooling lithium-ion battery during thermal runaway is proposed. The internal temperature and voltage of the battery, as well as the gases generated during thermal runaway are investigated. In addition, the extinguishing and cooling ability of the intermittent spray method at different intermittent periods (cycle consisting of a spray time and an interval time) and duty cycles (the percentage of the pulse duration occupied in a cycle) are compared and discussed. Furthermore, the toxic effects of the generated gases are evaluated. Experimental results reveal that the internal temperature of the battery is significantly higher than the surface temperature during the thermal runaway. Particularly, the internal temperature of the cell with 100% state of charge was as high as approximately 1000 ℃. In addition, the surface temperature of the cell may rebound after cooling owing to the insufficient heat transfer and a large radial temperature gradient of the battery. Furthermore, intermittent spray with more spray pulses of shorter duration performs better cooling effect. Particularly, the cooling effect initially increases, and then decreases with decreasing duty cycle. The major toxic gases produced during thermal runaway are CO and HF, whose yield increases with an increase in the state of charge, and the toxicity of these gases increases after the water spray. The findings of this study indicate that strict safety protection is needed when water spray is used to extinguish LIB fires. [ABSTRACT FROM AUTHOR]