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Plant factories have a great potential for mitigating the contradiction between the world’s growing population and food scarcity. During the process of its automatic production, machine vision plays a significant role. This technique almost covers every production link from raising seedlings, transplanting, management, and harvesting to fruit grading. To provide references and a starting point for those who are committed to studying this issue. In this paper, the application prospects of machine vision in plant factories were analyzed, and the present researches were summarized from the fields of plant growth monitoring, robot operation assistance, and fruit grading. The results found that although the existing methods have solved some practical problems at low cost, high efficiency and precision, some challenges still are faced by machine vision. Firstly, the changing lighting, complex backgrounds, and color similarity within plant different parts cause the commonly used image segmentation algorithms to fail. The shortage of standard agricultural datasets also keeps deep learning and unsupervised classification algorithms from making progress. Secondly, there are some theoretical knowledge gaps for machine vision application in a particular environment of plant factories, which seriously contains its application effect. Thirdly, the lack of special image acquisition devices and supporting facilities resulted in poor image quality. All these factors hinder machine vision application in plant factories. Nevertheless, it is still a powerful tool and irreplaceable at present. We believed that this technique would promote plant factory development greatly with more robust, efficient, and reliable algorithms are developed in the future.

To effectively alleviate the ever-increasing energy crisis and environmental issues, clean and sustainable energy-related materials as well as the corresponding storage/conversion devices are in urgent demand. Silicon (Si) with the second most elemental abundance on the crust in the form of silicate or silica (SiO2) minerals, is an advanced emerging material showing high performance in energy-related fields (e.g. batteries, photocatalytic hydrogen evolution). For the improved performance in industry-scale applications, Si materials with delicate nanostructures and ideal compositions in a massive production are highly cherished. On account of the reserve, low cost and diverse micro-nanostructures, silicate minerals are proposed as promising raw materials. In the article, crystal structures and the reduction approaches for silicate minerals, as well as recent progress on the as-reduced Si products for clean energy storage/conversion, are presented systematically. Moreover, some cutting-edge fields involving Si materials are discussed, which may offer deep insights into the rational design of advanced Si nanostructures for extended energy-related fields.

The layered materials have demonstrated great prospects as cost-effective substitutes for precious electrocatalysts in hydrogen evolution reaction. Research efforts have been devoted to synthesizing highly conductive MoS2 with the substantial cardinal plane and edge active sites. Here, we successfully synthesized a hierarchical 1T/2H–MoS2 with sodium ion insertion via a facile hydrothermal method. The contents of the 1T-phase can be flexibly controlled by different hydrothermal temperatures (160 °C ∼ 200 °C). And the modified uniformly dispersed 1T/2H–MoS2 nanospheres with different d spacings were designed to enhance the electrocatalytic efficiency by adding SiO2 and through the ion exchange process of NaOH and HF solution. The as-synthesized Na+ intercalated 1T-MoS2 nanosphere with an expanded interlayer of 0.95 nm obtained at 160 °C exhibits a prominent electrocatalytic performance of hydrogen evolution reaction with a comparable overpotential of 255 mV and a remarkably small Tafel slope of 44 mV/decade. Therefore, this study provides a facile and controllable strategy to yield interlayer-expanded 1T-MoS2 nanospheres, making it a potentially competitive hydrogen evolution catalyst for the hydrogen cell.

A fully mechanized mining face is characterized by serious dust pollution and dust is a major cause of pneumoconiosis that haunts numerous miners. For a fully mechanized face having large mining heights, the main dust source in the pavement area is produced by the moving support frame. To reduce the amount of dust during support's movement, the distribution and dissipation of dust in this process were studied by combining numerical simulations with underground measurements. The results showed that with an increase of the distance from the air inlet, the wind speed of the sidewalk in the fully mechanized face first increased, then decreased, and finally increased again. At the position of the coal cutter, the highest wind speed was 1.78 m/s and the average wind speed of the roadway was about 0.8 m/s. The dust concentration at the dust source was >1000 mg/m3. An area with a high dust concentration and having a length of 15 m was formed on the rooftop, together with a 50 m long dust belt with a dust concentration of 300 to 450 mg/m3 in the pavement area of 10 m from the dust source. Beyond the 45 m radius from the dust source, the dust concentration was stable at about 250 mg/m3. Based on the dust production characteristics of the support frame, an enclosed dust-guiding device was designed and structure-optimized. Based on the on-site field application test results, it was found that the device has a satisfactory dust-guiding effect during support movement and the dust suppression rate near the dust source reached 94.8%.

Indoor map is a fundamental element of indoor location-based services (ILBS). However, traditional indoor mapping techniques are labor-intensive and time-consuming. The advancement of smartphones offers great opportunities for crowdsourcing-based indoor mapping, which is one of the most promising applications due to its low cost and flexibility. Over the last decade, many crowdsourcing-based indoor mapping solutions using smartphones have been proposed. This article provides a systematic review of these works. Different from former surveys, we classify the indoor mapping process by the stage of map construction. In particular, we highlight the two key steps, geospatial-element acquisition, and indoor-map construction, and provide state-of-the-art techniques on these topics. Then, we systematically review the crowdsourcing-based indoor mapping solutions under grid-based, landmark-based, and semantic maps. In addition to covering the principles, benefits, and challenges, these systems are compared in terms of sensors, participation, output, experimental environment, and reported accuracy. Besides these existing performance criteria, we extract quantitative performance criteria that are suitable to evaluate crowdsourcing-based indoor mapping solutions. Finally, we present open issues and future research directions.

Summary Light-triggered smart nanochannels based on optoionic effects are currently explored in the fields of nanoconfined ion management and photoelectric conversion because of their noninvasive external field control, intelligent ion responses, and efficient photoelectric-conversion properties. Recent progress in generating chemical changes or electrochemical gradients with light and in manipulating the migration behavior of ions in nanoconfined channels is summarized here, with a focus on the construction strategies and the optoionic mechanisms involved. The tremendous challenges faced by light-triggered ion channels have been raised and the promising future is prospected.

The Charpy impact properties of 15Cr12MoVWN ferritic/martensitic steel for sodium-cooled reactors with variation in heat treatment factors and parameters are reported. The results show that the ductile-to-brittle transition temperature (DBTT) increased and the upper shelf energy (USE) decreased with increase in normalizing temperature. However, the variation tendency of DBTT and USE was the opposite with increase in tempering temperature. The tempering temperature showed a greater influence on USE than the normalizing temperature, and normalizing and tempering temperatures had the equally significant effects on DBTT, but the cooling method was not a significant factor for DBTT and USE. The prior austenite grain and M23C6 size were the main influences on DBTT, and the dislocation density was the main factor affecting the variation of USE. The heat-treatment regime recommended for 15Cr12MoVWN steel was composed of normalizing at 1000–1050 °C for 0.5 h followed by water quenching or air cooling and tempering at 760 °C for 1.5 h.

In cold regions, the long-term stability of engineering facilities is unavoidably influenced by the negative temperature, freeze-thaw process, dry-wet process, and dynamic loading conditions induced by earthquakes and traffic loads. In order to investigate the effects of different cyclic stress paths on the evolution of dynamic mechanical properties of frozen silt clay, a series of cyclic triaxial tests with variation confining pressure (VCP) or constant confining pressure (CCP) were performed. Triaxial low-temperature apparatus (MTS-810) was taken advantage of to simulating various cyclic stress paths by changing cyclic loading conditions of axial stress and confining pressure. In this paper, the evolution features of the axial resilient modulus, damping ratios, and the shape of hysteresis loops with an increase in the number of load cycles under different dynamic stress paths are comprehensively studied. The results show that the loading angle of cyclic stress path and the phase difference between cyclic axial stress and confining pressure are the main factors that remarkably affect the development characteristics of the resilient modulus and damping ratio. With increasing of the loading angle and phase difference, the resilient modulus increases, but damping ratio increases with increasing of loading angle and with decreasing of phase difference. With the continuous increase in the number of loading cycles, the samples of frozen soil show compacting and hardening characteristics. With an increase in the number of load cycles, the shape of hysteresis loop becoming narrows, the resilient modulus decreases at the initial stage and then gradually increases, and the damping ratio stably decreases. According to contrastively analyzing the evolution of dynamic parameters and the shape features of hysteresis loops under various cyclic stress paths, it can be clearly discovered that the evolution of sample microstructure and the development of dynamic characteristics of frozen samples have obvious dependence on the cyclic stress path. Therefore, the effects of variable confining pressure (VCP) on dynamic behaviors of frozen soils are nonnegligible in practical cold region engineering.

Severe surface hardening problems during laser surface texturing (LST) exert a remarkable influence on the tribological performance and fatigue strength of LST-treated components. Given this, an attempt is made to evaluate the effect of process parameters, including the energy density, the pulse frequency, and the scanning speed, on the hardness of laser surface textured 5A06 aluminum alloy based on response surface methodology. Firstly, a series of LST experiments were carried out by a nanosecond pulsed laser. Then, the predictive model correlating the process parameters with the hardness was established and tested for adequacy using analysis of variance. Sensitivity analysis was subsequently employed to identify and rank the significance of each process parameter. The results indicated that the developed model could effectively predict the hardness of laser surface textured 5A06 aluminum alloy. The scanning speed was found to be the dominant parameter, followed by the pulse frequency, and the energy density has the minimal influence. The graphical results revealed that the hardness gradually increases as the energy density and pulse frequency increases, while decreases as the scanning speed increases. This research could be used to select appropriate process parameters to manufacture high-performance surface textures with superior properties.

Summary The growth of the internet of things (IoT) is creating a demand for convenient energy sources, like organic photovoltaics, to power various small IoT devices. Here, we report a highly crystalline small molecular acceptor (named FCC-Cl) with an optical band gap of 1.71 eV suitable for indoor applications. The important design rationale of FCC-Cl is the combination of a weak electron-donating core and a moderate electron-withdrawing end group, which leads to needed band gap and high crystallinity. The OPVs based on D18:FCC-Cl achieved a high external quantum efficiency up to 85% and a high fill factor of 80% due to the high absorption coefficient and strong crystallinity of FCC-Cl. Consequently, an impressive power conversion efficiency of 28.8% was achieved under a 2,600 K LED lamp at 500 lux. It was also demonstrated that PM6:FCC-Cl-based devices can achieve high efficiencies over a wide range of active-layer thicknesses, which is a feature necessary for large-scale roll-to-roll printing processes.

Probing the dynamic evolution of active species under different sensing conditions is achieved to the rational design of sensing materials for outstanding sensing performance. In this study, a palladium (Pd)-loaded ZnO sensing material was approached via the impregnation method. The Pd-loaded ZnO₁₀₀ gas sensor has a better H₂ sensing performance than a pure ZnO gas sensor at an operating temperature of 190 to 360 °C. The in situ Raman and H₂ temperature-programmed surface reaction characterization technologies confirmed that the synergistic effect of metal Pd (Pd⁰) and Pd oxide (PdOₓ) played a decisive role in improving the sensing capability for H₂ in low concentrations (less than 100 ppm). The proportion of Pd⁰ in the Pd/PdOₓ dynamically increased with the elevation of operating temperature. The small size Pd/PdOₓ dispersed on the ZnO surface enhanced the dissociation of H₂ by Pd⁰ and the charge transfer between PdOₓ and ZnO, boosting the sensing performance of the gas sensor to H₂. With the increase of the operating temperature to more than 360 °C, H₂ was directly oxidized to gaseous H₂O on the Pd/PdOₓ active sites, resulting in a relatively low H₂ sensing capacity. In addition, the change of the appropriate Pd/PdOₓ ratio could effectively improve the H₂ sensing performance of the gas sensor.

In this paper, based on the two-step Ulm–Chebyshev iterative procedure and the Cayley transform, we propose a two-step Ulm–Chebyshev-like Cayley transform method for inverse eigenvalue problems. Un...

The carbon deposition and permeation on nickel surfaces were investigated from thermodynamic and kinetic aspects by using density functional theory (DFT), ab initio atomic thermodynamics, and class...

Poor charge separation efficiency of semiconductors often stands in the way of photoelectrochemical (PEC) water splitting realization. In this report, a surface polarized TiO2 photoanode is obtained via −OH moiety decoration, which achieves a fundamentally improved charge separation efficiency of about 94% at 1.23 VRHE. Detailed data shows that these hydroxyls with electric dipoles polarize the surface, inducing substantial electric field in the surface region, and elevating band edges so as to form a homojunction within TiO2. Such serves as the direct driving force for the photogenerated charge separation and migration. Moreover, these hydroxyls also facilitate water oxidation kinetics. Without typical doping or cocatalyst, surface polarized TiO2 photoanode delivers a considerably increased photocurrent density of about 1.41 mA·cm−2 at 1.23 VRHE (AM 1.5 G) and a cathodic shift on onset potential over 200 mV. This report highlights new opportunities to modulate charge separation by surface polarization for the construction of robust photoanodes.

In permafrost regions, construction of a channel involves a large amount of excavation activities and changes to surface water body, which can exert great impacts on the thermal regimes of permafrost underlying. In this paper, a coupled mathematical model of heat and moisture transfer was constructed for freeze-thaw soils to investigate the long-term thermal regimes of subgrade beneath a drainage channel built on the Qinghai-Tibet Plateau. Based on the numerical simulations, the thermal regimes of the subgrade both in warm and cold seasons were analyzed within a period of 50 years, as well as the impact of the widths of the channel. The results showed that the channel excavation and flowing water within could lead to a significant underlying permafrost degradation. During the first 30 years, the permafrost beneath the channel mainly experienced a rapid downward degradation. After that, the lateral thermal erosion of the flowing water led to a rapid permafrost degradation beneath the slope of the channel. In cold seasons, the shallow ground beneath the channel would not refreeze due to the flowing water and the thaw bulb actually expanded throughout the year. For the channel with a bottom width of 15 m, the thaw bulb beneath the channel could expand laterally to the natural ground about 10 m far away from the slope shoulder of channel till the 50th year. With different widths, the long-term thermal regimes of the subgrade beneath the channels differed considerably and the maximum difference was at the slope toe of the embankment. With the numerical simulated results, it is recommended that a channel built on permafrost should be wide-and-shallow rather than narrow-and-deep if conditions permit.

The convenient preparation of N2-unprotected five-membered cyclic guanidines was achieved through a cascade [3 + 2] cycloaddition between organo-cyanamides and α-haloamides under mild conditions in good to excellent yields (up to 99%). The corresponding cyclic guanidines could be easily transformed into hydantoins via hydrolysis.

Straw return is an effective way to improve crop grain yield and potassium (K) use efficiency by increasing soil K content. However, the effects of straw return on soil K supplying capacity, replacement of K fertilizer, and K-use efficiency under maize (Zea mays L.)–rice (Oryza sativa L.) cropping systems are little studied. A two-year field experiment was conducted to determine the physiological determinants of K-use efficiency under straw return with four K fertilization rates. Sr33 (straw returned plus 33% of K fertilizer applied) and Sr67 (straw returned plus 67% of K fertilizer applied) increased annual crop yields by 1.5% and 3.2% and increased agronomic K-use efficiency by respectively 2.9 and 1.3-fold on average in the two years, compared with the conventional practice S0K100 (no straw returned plus normal amounts of K fertilizer applied). The Sr33 and Sr67 treatments resulted in significantly greater equilibrium K concentration ratios (CR0K) and specifically exchangeable K (KX) values according to quantity/intensity (Q/I) relationship analyses, indicating improvement of the potential soil K supply capacity. However, the Sr67 better maintained the soil exchangeable K level and K balance. The results suggested that K released from maize and rice straw can replace about half of chemical K fertilizer, depending on the available K content in maize–rice cropping system production.

The shear behavior of the frozen soil−structure interface is important for accurately predicting the interface responses of structures adopted in the cold regions. The purpose of this study is to experimentally and theoretically investigate the shear behavior of frozen clay–concrete interface under engineering conditions. A large-scale direct shear apparatus with a temperature-controlled shear box is used to test the interface behavior. Test specimens consisting of a cement concrete block and frozen soil with initial water content ranging between 14.6% and 24.6% were prepared at different conditions of temperatures (15.4 to −9.8 °C), shear rates (0.03–0.9 mm min−1), and normal stresses (50–200 kPa). It is found that the peak shear strength is linear developing with increasing of normal stress, initial water content, and temperature. It increased from 67.7 to 133.3 kPa as the initial water content increased from 14.9% to 24.6% at temperature of −6.8 to −6.6 °C, and it increased from 51.2 to 80.6 kPa with temperature decreasing from 15.4 to −9.8 °C at initial water content of 14.6%–14.9%, furthermore it has a power law relationship with shear rate. The final vertical displacement increases with the decreasing temperature, and increasing initial water content. While, it is slight or could be ignored at lower shear rates (e.g. 0.03 mm min−1 and 0.15 mm min−1) and it is −0.25 mm and −0.28 mm at shear rate of 0.3 mm min−1 and 0.9 mm min−1, respectively. In addition, the evolution of vertical displacement also varies with test condition, the growth rate at beginning increases with increasing initial water content and decreasing temperature or ice content, which is because of the ice film effects the particle size. Moreover, a disturbed state concept model combined with linear and nonlinear characteristics is developed to describe the interface shear behavior. The disturbance D reflects the interface mechanical response and responds differently trend for different test conditions, increasing faster with increasing temperature and decreasing initial water content or shear rate. The testing results, including the test and model results, can be used to simulate the performance of engineered geotechnical assets such as earth dams or irrigation channels with concrete linings in cold regions.

In this paper, TiO2 decorated reduced graphene oxide nanocomposite (TiO2@RGO), synthesized with the help of 3-Triethoxysilylpropylamine (APTES), was utilized to reinforce polyimide (PI), and the me...

In the Loess Plateau in Northern China, repeated freeze-thaw (FT) cycles deteriorate the strength and structure of loess as a foundation soil, resulting in the instability or failure of supporting structure. Lignosulfonate is an eco-material, utilized as an effective and nontraditional stabilizer to improve the engineering properties of metastable soils. A series of laboratory tests, including unconfined compression tests, cyclic loading-unloading tests and scanning electron microscopy, on calcium lignosulfonate (CL)- and sodium lignosulfonate (SL)-stabilized loess were performed to investigate the stabilization effect, deterioration mechanisms of the FT cycles, and the resistance to FT cycles. Two traditional stabilizers, quicklime (QL) and sodium silicate (SS), were selected, and the engineering properties of QL- and SS-stabilized loess were compared with those of CL- and SL-stabilized loess. The results showed that the strength values of CL- and SL-stabilized loess specimens decreased by 34.2% and 50% respectively, after 20 FT cycles, whereas those of the traditionally SS- and QL- stabilized specimens decreased by 85.3% and 82.87%, respectively. The elastic moduli of SL- and QL-stabilized loess specimens decreased by 22.1% and 92.0%, respectively. The mean energy dissipations of nontraditionally treated specimens also decreased significantly less than those of traditionally treated specimens. Overall, the results showed CL and SL had better stabilization effects on engineering properties of loess than QL and SS, and their stabilized loess specimens exhibited stronger resistance to FT cycles. The study findings demonstrated the significant potential of lignosulfonate for extensive application in cold loess areas.

The reduction of nitrogen-containing heterocyclic compounds in aqueous medium under mild condition is quite challenging. In view of metal–organic frameworks (MOFs) possess adjustable pore size and modifiable organic linkers, MOFs could be used in heterogeneous catalysis. Herein, Three Nano-Ni-MOFs, MOF-74-Ni, MOF-69-Ni, and Ni–NH2 (constructed from similar ligands and Ni2+ ions) are introduced for hydrogenating of azacyclo-compounds. As expected, Ni–NH2 shows outstanding activity of hydrogenation of quinoline under mild conditions, due to the moderate pore size and the modified –NH2 function group, which makes the substrate anchored on the surface of the framework facilitate the following catalysis process. Theoretical calculations identified that the –NH2 group at the catalyst facilitates the H2 heterolytic dissociation for the hydrogenation reactions. Compared to MOF-74-Ni and MOF-69-Ni, the catalyst of Ni–NH2 shows outstanding activity of hydrogenation of quinoline, due to the modified –NH2 function group which makes the substrate anchored on the surface of the framework facilitate the following catalysis process

To understand the dominance of 2,2′-((2Z,2′Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2′′,3′′:4′,5′]thieno[2′,3′:4,5]pyrrolo[3,2-g]thieno[2′,3′:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (Y6) and its derivatives leading to the rapid efficiency rise of organic solar cells (OSCs), solid film structures are of significant importance. Here, we employ cryo-transmission electron microscopy (Cryo-TEM) to resolve the landscape of Y6 packing in neat films (unlike single crystals) in relation to device performance, and reveal how processing with carbon disulfide and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) influences its molecular packing, prominently the backbone ordering. We show that Y6 prefers a face-on dominant packing structure with an in-plane long-range conjugated backbone packing in films. The long-range backbone ordering is beneficial for reducing disorders on the energy distribution of the electron transport level, thereby improving the carrier lifetime in heterojunctions. We confirm that long-range energy transfer assists poly[(2,6-(4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)-benzo[1,2-b:4,5-b′]dithiophene))-alt-(5,5-(1′,3′-di-2-thienyl-5′,7′-bis(2-ethylhexyl)benzo[1′,2′-c:4′,5′-c′]dithiophene-4,8-dione))] (PM6) excitons to reach the preferred Y6/PM6 interfaces without being quenched by PC71BM clusters, yielding no signs of bimolecular recombination and a high power conversion efficiency of 16.8%. Our results suggest an effective molecular packing structure in solid films, and the prominent role of backbone ordering in photoelectric conversion processes, which will outline the future development of OSCs.

Platinum (Pt) is an excellent electrocatalyst for cathode and anode reactions in direct methanol fuel cells (DMFCs). However, constructing nanostructures with efficient Pt utilization and electrocatalytic activity is a major challenge for the oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) in an acidic medium. Herein, we describe a facile strategy to prepare high activity graphene quantum dot composited Pt nanotubes arrays (GQD–Pt NTAs) with an available porous surface through an electro-codeposition approach. Benefiting from the difference in size between graphene quantum dots and Pt nanoparticles, the GQD–Pt NTAs possess an adjustable porous structure. Moreover, the increased porosity of the GQD–Pt NTAs improves the effective availability of the Pt surface, significantly enhancing the electrocatalytic activity with a high current density of 1.14 mA μgPt−1 at 0.90 V (vs. RHE) and 2227.08 mA mgPt−1 at 0.85 V (vs. RHE) for the ORR and MOR, respectively. This work suggests that combining Pt with nonmetallic quantum dots is indeed an effective approach to address the unsatisfactory utilization and electroactivity of Pt-based nanomaterials.

Two FREAs, IUIC-O and IUIC-T, based on an undecacyclic core were developed. IUIC-T having a higher extinction coefficient affords aligned energy levels with PBDB-T, finer nanoscale morphology and more orderly molecular stacking, thus achieving more efficient exciton dissociation and charge transport. Therefore, the PBDB-T:IUIC-T based OSC gains a higher PCE of 13.05%.

Diketopyrrolopyrroles (DPP) have been recognized as a promising acceptor unit for construction of semiconducting donor-acceptor (D-A) polymers, which are typically flanked by spacers such as thiophene rings via a carbon-carbon single bond formation. It may suffer from a decrease in the coplanarity of the molecules especially when bulky side chains are installed. In this work, the two N atoms in the DPP unit are further fused with C-3 of the two flanking thiophene rings, yielding a p-expanded, very planar fused-ring building block (DPPFu). A novel DPPFu-based D-A copolymer (PBDTT-DPPFu) was successfully synthesized, consisting of a benzo[1,2-b:4,5-b]dithiophene (BDTT) unit as a donor and a DPPFu unit as an acceptor. For comparison, the unfused DPP-based counterpart PBDTT-DPP was also synthesized. Two dodecyl alkyl chains were attached to thiophene rings of DPP moieties to ensure good solubility of the DPPFu-based polymer. The influence of the ring-fusion effect on their structure, photophysical properties, electronic properties, molecular packing, and charge transport properties is investigated. Ring-fusion enhances the intermolecular interactions of PBDTT-DPPFu polymer chains as indicated by density functional theory calculation and analysis of electrostatic potential and van der Waals potential and results in significantly improved molecular packing for both the in-plane and out-of-plane directions as suggested by X-ray measurements. Finally, we correlate the molecular packing to the device performance by fabricating field-effect transistors based on these two polymers. The charge carrier mobility of the ring-fused polymer PBDTT-DPPFu is significantly higher as compared to the PBDTT-DPP polymer without ring-fusion, although PBDTT-DPPFu exhibited a much lower number-average molecular weight of 17 kDa as compared to PBDTT-DPP with a molecular weight of 108 kDa. The results from our comparative study provide a robust way to increase the interchain interaction by ring-fusion-promoted coplanarity. Funding Agencies|Swedish Research CouncilSwedish Research CouncilEuropean Commission [2015-04853, 2016-06146, 2019-04683]; Swedish Research Council FormasSwedish Research CouncilSwedish Research Council Formas; NSFCNational Natural Science Foundation of China (NSFC) [21504006, 21534003, 11272093]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [2017.0186, 2016.0059]; Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research; China Scholarship CouncilChina Scholarship Council [201908440047]; Guangzhou Municipal Science and Technology Bureau [201804010501, 201904010381, 202002030362]; Department of Education of Guangdong ProvinceNational Natural Science Foundation of Guangdong Province [2018GKTSCX041, 2017GKQNCX005]; Department of Science and Technology of Guangdong Province [2016A010103046]; Open Fund of the State Key Laboratory of Luminescent Materials and Devices (South China University of Technology) [2020-skllmd-07]; Natural Science Foundation of Hunan ProvinceNatural Science Foundation of Hunan Province [2018JJ3098]; Office of Science, Office of Basic Energy Sciences, of the U.S. Department of EnergyUnited States Department of Energy (DOE) [DE-AC02-05CH11231]

In this work, we attempt to figure out alkoxy-substitution effects on two kinds of well-known non-fullerene acceptors (NFAs), IDT-series and Y-series acceptors, by placing alkoxy side chains on the β-positions of the outer thiophene units. The resulting molecules, named IDTN-O and Y6-O, exhibit different properties compared to the original acceptors named IDTN and Y6. The HOMO and LUMO levels of IDTN-O are slightly upshifted at the same time, which causes a slightly higher open-circuit voltage (Voc) without sacrificing the short-circuit current density (Jsc) of the devices. J71:IDTN-O blend films can also achieve a better blend morphology due to the conformational locking effect and higher dipole moment induced by the alkoxy groups, which helps achieve a higher fill factor (FF). In addition, Y6-O exhibits significantly upshifted LUMO levels compared to Y6, leading to a high Voc of 0.95 V. PM6:Y6-O blend films can also maintain an optimal blend morphology through side-chain engineering, which leads to an excellent FF of 78.0%. As a result of alkoxy substitution, both IDTN-O and Y6-O-based devices can achieve better performances of 12.1% and 16.6% than IDTN and Y6-based devices (10.9% and 15.7%), which indicates that this is an effective method to optimize these two types of NFAs.

Good control of the morphology, particle size, and wettability of silica nanoparticles is of increasing importance to their use in a variety of fields. Here, we propose a strategy to tune the surface wettability of nanosilica by changing the dosage of a chemical modifier. A series of measurements, including scanning electron microscopy (SEM), laser scatting technique, Fourier transform infrared (FTIR) spectroscopy, thermogravimetry, and surface hydroxyl number and water contact angle measurement, were conducted to verify the surface chemistry and wettability of these nanoparticles. Through controlled chemical modification, the contact angle of the treated nanoparticles increases from 34.7 to 155° with increasing amount of dichlorodimethylsilane (DCDMS) within a molar ratio (MR) between DCDMS and nanoparticles of 5.17. The number of hydroxyl groups covered on the particle surface decreases gradually from 1.79 to 0.47, and the surface grafting rate could reach 73.7%. As the addition of dichlorodimethylsilane equals MR 5.17, the contact angle reaches the maximum value of 155°, which displays excellent superhydrophobicity. After surpassing the point of MR 5.17, the contact angle does not increase but starts to decrease, ultimately remaining stable at 135°. It can be concluded that the surface wettability of nano-SiO2 particles can be precisely modulated by varying the amounts of the modifier. Furthermore, the modulating mechanism of the process occurring on the surface of SiO2 particles has been investigated at the molecular level.

Double-maize cropping system is an effective option for coping with climate change in the North China Plain. However, the effects of changes in climate on the growth and yield of maize in the two seasons are poorly understood. Forty-six cultivars of maize with different requirements for growing degree days (GDD), categorized as high (H), medium (M) or low (L), and three cultivar combinations for two seasons as LH (using JD27 and DMY1 from category L in the first season; and YD629 and XD22 from category H in the second season), MM (using JX1 and LC3 from category M in the first season; and ZD958 and JX1 from category M in the second season) and HL (using CD30 and QY9 from category H in the first season; and XK10 and DMY3 from category L in the second season) were tested to examine the eco-physiological determinants of maize yield from 2015 to 2017. The correlations between the combinations of cultivars and grain yield were examined. The combination LH produced the highest annual grain yield and total biomass, regardless of the year. It was followed, in decreasing order, by MM and HL. Higher grain yield and biomass in LH were mainly due to the greater grain yield and biomass in the second season, which were influenced mainly by the lengths of the pre- and post-silking periods and the rate of plant growth (PGR). Temperature was the primary factor that influenced dry matter accumulation. In the first season, low temperatures during pre-silking decreased both the duration and PGR in LH, whereas high temperatures during post-silking decreased the PGR in MM and HL, resulting in no significant differences in biomass being observed among the three combinations. In the second season, high temperatures decreased both the PGR and pre- and post-silking duration in MM and HL, and consequently, the biomass of those two combinations were lower than that in LH. Moreover, because of lower GDD and radiation in the first season and higher grain yield in the second season, production efficiency of temperature and radiation (Ra) was the highest in LH. More importantly, differences in temperature and radiation in the two seasons significantly affected the rate and duration of growth in maize, and thereby affecting both dry matter and grain yield. Our study indicated that the combination of LH is the best for optimizing the double-maize system under changing climatic conditions in the North China Plain.

Brassica napus is an important oilseed crop in the world and the mechanism of seed oil biosynthesis in B. napus remains unclear. In order to study the mechanism of oil biosynthesis and generate germplasms for breeding, an EMS mutant population with ~100,000 M2 lines was generated using Zhongshuang 11 as the parent line. The EMS-induced genome-wide mutations in M2-M4 plants were assessed. The average number of mutations including single nucleotide polymorphisms and insertion/deletion in M2-M4 was 21,177, 28,675 and 17,915, respectively. The effects of the mutations on gene function were predicted in M2-M4 mutants, respectively. We screened the seeds from 98,113 M2 lines and 9,415 seed oil content and fatty acid mutants were identified. We further confirmed 686 mutants with altered seed oil content and fatty acid in advanced generation (M4 seeds). Five representative M4 mutants with increased oleic acid were re-sequenced and the potential causal variations in FAD2 and ROD1 genes were identified. This study generated and screened a large scale of B. napus EMS mutant population and the identified mutants could provide useful genetic resources for the study of oil biosynthesis and genetic improvement of seed oil content and fatty acid composition of B. napus in the future. Accepted version This research was supported by The National Key Research and Development Program of China (2016YFD0101000) and the National Natural Science Foundation of China (31871658).

In recent years, photovoltaic devices based on inorganic–organic hybrid perovskite materials have become one of the most promising research subjects in the field of energy conversion. CH3NH3PbI3 st...

To achieve the satisfactory performance of WiFi fingerprinting-based indoor localization, additional access point (AP) deployment is usually required in some environments. How to place these additional APs is a problem. The current AP placement methods do not consider the existing APs. In this letter, we propose a novel AP placement method for WiFi fingerprinting that considers existing APs. The parameters of the radio propagation model are first obtained based on data collected from the existing APs. Then, based on the self-learning parameters, we perform a genetic algorithm (GA)-based optimization method for AP placement. The experimental results demonstrate the effectiveness of the proposed method.

Wetness is one of the important physical parameters of snowpack. Its spatial and temporal changes play a key role in snowmelt runoff forecast, regional climate change, and agricultural irrigation. In this study, we proposed a new method to retrieve snow wetness from full-polarimetric synthetic aperture radar (SAR) data. First, the dominant scattering components, i.e. surface and volume scattering, in wet-snow conditions were obtained by polarimetric decomposition. The random rough surface scattering models and the dense media radiative transfer (DMRT) model were then used to establish the surface and volume scattering models, through which the surface and volume scattering lookup tables were created, respectively. Based on the lookup tables and the polarimetric decomposition results, the snow surface and volume wetness were retrieved, respectively. Finally, the effective snow wetness was derived from the weighted summation of surface and volume wetness. The advantage of this method mainly comes from the full consideration the snow surface roughness, the local incidence angle on complex mountain terrain, and the polarimetric information. In experiments, the GaoFen-3 data obtained on January 17, 2018 in the Kelan River Basin and the Radarsat-2 data obtained on March 19, 2014 in the Manasi River Basin were selected to verify the applicability of the proposed method at different conditions. From the analysis of experiment results, the correlation coefficient between the estimated and the ground measured snow wetness in the Kelan River Basin is 0.72. The mean absolute error (MAE) and the root mean square error (RMSE) are 3.35% and 3.89%, respectively. The correlation coefficient between the snow wetness estimated by Radarsat-2 and the measured values in the Manasi River Basin is 0.62. MAE and RMSE are 1.32% and 1.62%, respectively. These results proved that the proposed method can effectively retrieve snow wetness under different SAR data, different areas, and different snow periods.

Innovative approaches and tools play an important role in shaping design, characterization and optimization for the field of photonics. As a subset of machine learning that learns multilevel abstraction of data using hierarchically structured layers, deep learning offers an efficient means to design photonic structures, spawning data-driven approaches complementary to conventional physics- and rule-based methods. Here, we review recent progress in deep-learning-based photonic design by providing the historical background, algorithm fundamentals and key applications, with the emphasis on various model architectures for specific photonic tasks. We also comment on the challenges and perspectives of this emerging research direction. The application of deep learning to the design of photonic structures and devices is reviewed, including algorithm fundamentals.

N-halamine-containing mesoporous silica was prepared by treating the silica with (3-(trimethoxysilyl) propyl methacrylate), followed by grafting reaction of an N-halamine precursor, 3-(3′-hydroxypropyl)-5,5-dimethylhydantoin (APDMH). The resulting N-halamine mesoporous silica was applied to the surface of cotton by a coating process. The coated cotton showed good static and dynamic hydrophobic properties (static contact angle, 138.91°). After soaking in household bleach, N-halamines were formed on the coated fabric, which provided good antimicrobial properties against Gram-positive bacteria, Gram-negative bacteria, and fungi. The chlorinated sample inactivated 98.93% of Staphylococcus epidermidis, 97.83% of Escherichia coli O157:H7 and 82.24% of Candida albicans within 60 min, respectively. The coated and chlorinated samples showed high hydrophobicity toward other water-based liquids such as coffee, cola, green tea and milk. Further, the chlorinated fabric samples degraded ammonia in aqueous solutions. These attractive functions make the new N-halamine mesoporous silica coated cotton fabrics as an excellent candidate of multipurpose functional fibrous materials.

Carbon catabolite repression (CCR), which is mainly mediated by Cre1 and triggered by glucose, leads to a decrease in cellulase production in Trichoderma reesei. Many studies have focused on modifying Cre1 for alleviating CCR. Based on the homologous alignment of CreA from wild-type Penicillium oxalicum 114-2 (Po-0) and cellulase hyperproducer JUA10-1(Po-1), we constructed a C-terminus substitution strain-Po-2-with decreased transcriptional levels of cellulase and enhanced CCR. Results revealed that the C-terminal domain of CreAPo-1 plays an important role in alleviating CCR. Furthermore, we replaced the C-terminus of Cre1 with that of CreAPo-1 in T. reesei (Tr-0) and generated Tr-1. As a control, the C-terminus of Cre1 was truncated and Tr-2 was generated. The transcriptional profiles of these transformants revealed that the C-terminal chimera greatly improves cellulase transcription in the presence of glucose and thus upregulates cellulase in the presence of glucose and weakens CCR, consistent with truncating the C-terminus of Cre1 in Tr-0. Therefore, we propose constructing a C-terminal chimera as a new strategy to improve cellulase production and alleviate CCR in the presence of glucose.

Lined seahorse (Hippocampus erectus), an important economic and medicinal fish in China, exists widely in Atlantic Ocean. However, habitat destruction for its spawning and overfishing has led to profound decline the wild populations in recent years. Therefore, to improve the molecular-assisted selection (MAS) and resources conservation of H. erectus, the 100 novel single nucleotide polymorphism (SNP) loci are developed by restriction-site associated DNA (RAD) sequencing in this species. In the present study, the observed heterozygosity (Ho) and expected heterozygosity (HE) varied from 0.0263 to 0.8154 and 0.0261 to 0.506, respectively. The minor allele frequency (MAF) ranged from 0.0132 to 0.5000. The PIC value was between with 0.0257 and 0.375. Fifteen loci displayed prominent deviations from the Hardy–Weinberg equilibrium (HWE) after Bonferroni correction (P

Background Lymantria dispar is an economically impactful forest pest worldwide. The entomopathogenic fungi Beauveria bassiana shows great promise in pest management due to its high lethality in Lymantria dispar. A complete understanding of the immune interactions between the pest and the pathogenic fungus is essential to actualizing biological pest management. Results Following the infection of Lymantria dispar by Beauveria bassiana spores, we performed a time-course analysis of transcriptome in Lymantria dispar fat bodies and hemocytes to explore host immune response. A total of 244 immunity-related genes including pattern recognition receptors, extracellular signal modulators, immune pathways (Toll, IMD, JNK and JAK/STAT), and response effectors were identified. We observed contrasting tissue and time-specific differences in the expression of immune genes. At the early stage of infection, several recognition receptors and effector genes were activated, while the signal modulation and effector genes were suppressed at later stages. Further enzyme activity-based assays coupled with gene expression analysis of prophenoloxidase revealed a significant upregulation of phenoloxidase activity at 48- and 72-h post-infection. Moreover, fungal infection led to dysbiosis in gut microbiota that seems to be partially attributed to reduced gut hydrogen peroxide (H2 O2 ) amount, which indicates a significant impact of fungal infection on host gut microbes. Conclusion Our study provides a comprehensive sequence resource and crucial new insights about an economically important forest pest. Specifically, we elucidate the complicated multipartite interaction between host and fungal pathogen and contribute to a better understanding of Lymantria dispar anti-fungal immunity, resulting in better tools for biological pest control.

Identifications of rotating sound sources are of interest in many industrial applications. The most famous beamforming to identify rotating sound source is the time-domain ROSI beamforming proposed by Sijtsma et al. (AIAA 2001-2167, 2001). Nowadays ROSI is still the unique widely recognized beamforming for array with arbitrary microphone configuration to identify rotating sound source. De-Dopplerisation is essential for beamforming to identify a moving sound source. This paper is devoted to the identification and elimination of the Doppler effect in ROSI. A non-zero source with a fundamental frequency may induce ghost contributions in ROSI at other scan points different from this source position, at all side band frequencies to the fundamental frequency with a modulation frequency equal to the rotation frequency. A rotational symmetry array with respect to rotation axis of sound source can be used to eliminate the ghost contributions in ROSI at side bands that are not non-zero integer multiples on the order of rotational symmetry with respect to the rotation axis of sound source of the array.

Potassium supported on commercial activated carbon (K/AC) catalysts were prepared and used for catalytic fast pyrolysis (CFP) of walnut shell to produce phenolic-rich bio-oil. Pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) and fixed-bed CFP tests were performed to reveal the influences of pyrolytic temperature, potassium loading and catalyst-to-biomass (C-to-B) ratio on the product distribution. The Py–GC/MS results showed that the K5.79/AC catalyst in which the potassium loading was 5.79% exhibited the maximal improvement on the yield of phenolic compounds. Pyrolytic temperature significantly affected the total phenolic yield, which achieved the maximum value at 450 °C whether with or without catalysts. Moreover, the C-to-B ratio also dramatically affected the yield of phenolic compounds. The total phenolic yield raised with increasing C-to-B ratio, whereas the excessive C-to-B ratio (higher than 3:1) would lead to an obvious decrease in total phenolic yield. Overall, the yield of total phenolic compounds achieved the maximum value of 145.65 mg/g (14.57 wt%) at 450 °C under C-to-B ratio of 3:1 in Py–GC/MS runs. Meanwhile, the lab-scale experiments obtained the maximal total phenolic yield of 135.13 mg/g (13.51 wt%) at 450 °C under C-to-B ratio of 1:3.

In the context of sea‐level rise (SLR), an understanding of the spatial distributions of mangrove flora and fauna is required for effective ecosystem management and conservation. These distributions are greatly affected by tidal inundation, and surface elevation is a reliable quantitative indicator of the effects of tidal inundation. Most recent studies have focused exclusively on the quantitative relationships between mangrove‐plant zonation and surface elevation, neglecting mangrove fauna. Here, we measured surface elevation along six transects through the mangrove forests of a subtropical estuarine wetland in Zhenzhu Bay (Guangxi, China), using a real‐time kinematic global positioning system. We identified the mangrove plants along each transect and investigated the spatial distributions of arboreal, epifaunal, and infaunal molluscs, as well as infaunal crabs, using traditional quadrats. Our results indicated that almost all mangrove forests in the bay were distributed within the 400–750 m intertidal zone, between the local mean sea level and mean high water (119 cm above mean sea level). Mangrove plants exhibited obvious zonation patterns, and different species tended to inhabit different niches along the elevation gradient: Aegiceras corniculatum dominated in seaward locations while Lumnitzera racemosa dominated in landward areas. Mangrove molluscs also showed distinct patterns of spatial zonation related to surface elevation, independent of life‐form and season. The spatial distributions of some molluscs were correlated to the relative abundances of certain mangrove plants. In contrast, the spatial distributions of crabs were not related to surface elevation. To the best of our knowledge, this is the first study to explicitly quantify the influences of surface elevation on the spatial distributions of mangrove fauna. This characterization of the vertical ranges of various flora and fauna in mangrove forests provides a basic framework for future studies aimed at predicting changes in the structure and functions of mangrove forests in response to SLR., The spatial distributions of mangrove plants and molluscs showed obvious patterns of zonation correlating with surface elevation. Mangrove flora and fauna within each habitat niche occupied distinct vertical ranges along the elevation gradient, irrespective of season. This is the first quantitative study to explicitly examine the influences of surface elevation on the spatial distributions of mangrove fauna within the intertidal zone.

Long noncoding RNAs (lncRNAs) play important roles in the process of cell fate determination. However, their function and expression profiles have not yet been systematically investigated during the transdifferentiation of glial precursor cells derived from dorsal root ganglia (DRG) in the peripheral nervous system. Our results demonstrated significant differences in gene architecture and expression among the three transcript types (lncRNA, mRNA, and TUCP). Distinct differences in transcript length, exon number, and ORF length were identified between lncRNAs and mRNAs after comparative analysis of their structure and sequence conservation. We found that the upregulated lncRNAs outnumbered the downregulated lncRNAs in glial precursor cells cultured with proBDNF antiserum compared with the levels in glial precursor cells cultured without proBDNF antiserum. By a series of GO and KEGG analyses, we found that the effects of some lncRNAs on their target genes in cis were related to nerve growth factor-induced cell cycle, cell phenotype change, and neuronal differentiation. The qRT-PCR verification results of lncRNAs ENSRNOT00000091991, ENSRNOT00000087717, and LNC000429 were mostly consistent with the sequencing results. The candidate lncRNAs may be associated with the neuronal transdifferentiation of glial precursor cells. Our study provides the first evidence for a remarkably diverse pattern of lncRNA expression during neuronal differentiation of glial precursor cells from rat DRG and also provides a resource for lncRNA studies in the field of cell differentiation.

Well Zhongqiu 1 obtained highly productive oil-gas stream in the footwall of Zhongqiu structure, marking the strategic breakthrough of Qiulitag structural belt in the Tarim Basin. However, the oil and gas sources in Zhongqiu structural belt and the reservoir formation process in Zhongqiu 1 trap remain unclear, so study on these issues may provide important basis for the next step of oil and gas exploration and deployment in Qiulitage structural belt. In this study, a systematic correlation of oil and gas source in Well Zhongqiu 1 has been carried out. The oil in Well Zhongqiu 1 is derived from Triassic lacustrine mudstone, while the gas is a typical coal-derived gas and mainly from Jurassic coal measures. The oil charging in Well Zhongqiu 1 mainly took place during the sedimentary period from Jidike Formation to Kangcun Formation in Neogene, and the oil was mainly contributed by Triassic source rock; large-scale natural gas charging occurred in the sedimentary period of Kuqa Formation in Neogene, and the coal-derived gas generated in the late Jurassic caused large-scale gas invasion to the early Triassic crude oil reservoirs. The Zhongqiu 1 trap was formed earlier than or at the same period as the hydrocarbon generation and expulsion period of Triassic-Jurassic source rocks. Active faults provided paths for hydrocarbon migration. The source rocks-faults-traps matched well in time and space. Traps in the footwall of the Zhongqiu structural fault have similar reservoir-forming conditions with the Zhongqiu 1 trap, so they are favorable targets in the next step of exploration.

Permafrost is sensitive to both climate warming and engineering disturbance on the Qinghai–Tibet Plateau (QTP). These factors degrade the stability of infrastructure built on permafrost and reduce its service life. To counter these effects, cooling of the subgrade to lower permafrost temperature forms part of the engineering design on the QTP. Proactive cooling of the subgrade has been used in construction of the Qinghai–Tibet Railway (QTR), the Chaidaer–Muli Railway, the Qinghai–Tibet DC Power Transmission Line, and the Gonghe–Yushu Express Highway. As a consequence, there has been significant ground cooling and little permafrost thaw beneath these infrastructure projects. However, the QTR has experienced some problems, such as in the stability of transitions at bridge abutments, reductions to the convective capacity of crushed rock structures from infilling by eolian sand, and freeze–thaw damage. A monitoring network has been established to examine the influence of climate change for engineering stability on the QTP. Climate warming on the plateau will present significant challenges for engineering of proposed oil and gas pipelines, express highways and the high‐speed railway from Golmud to Lhasa.

To achieve efficient doping in polymer solar cells (PSCs), the dopant needs to be selectively located in the binary components of a bulk heterojunction (BHJ) film according to its polarity. The rarely studied n-type dopant is thoroughly examined in a simplified planar heterojunction (PHJ) device to address its favored location in the active layer. Results show that the n-dopant distribution in the acceptor layer or at the donor/acceptor interface produces enhanced device performance, whereas it harms the device when located in the donor layer. Based on the results, the benefit of n-type doping is then transferred to the highly efficient BHJ devices via a sequential coating procedure. The performance improvement is closely linked to the variations in the dopant's location in the BHJ film, which is carefully examined by the synchrotron techniques with delicate chemical sensitivity. More interestingly, the sequential coating procedure can be easily extended to the p-doped device only by changing the dopant's polarity in the middle layer. These findings pave the way for ambipolar doping in PSCs and enable performance improvement by molecular doping within the expectations.

This paper analyzed the pore structure, quantified the pore fractal dimension, calculated the grading index (GI) of mixed aggregate, and studied the relationship among GI, pore structure, and strength to describe the cross-scale characteristics of backfill, which is made from stone powder and cemented tailing. A series of experiments were conducted on stone powder cement tailings backfill (SPCTB). The GI formulas for mixed aggregates, containing stone powder and tailings, were derived based on the Fuller theory. The nuclear magnetic resonance (NMR) fractal dimensions of backfills were derived using fractal geometry principles. Compared to the mesopore and macropore fractal dimensions, the correlation between micropore fractal dimension and macro-properties in terms of NMR porosity, pore structure complexity, uniaxial compression strength (UCS), and GI is the most significant. Macropore fractal dimension is generally correlated with UCS and GI and the other properties such as the shape of mixed aggregates also have an impact on fractal dimension. However, mesopore fractal dimension has no obvious relationship with macro-properties. Finally, the relationship between GI and UCS was studied, which contributed to improving backfill’s strength and optimizing gradation.

Loading of ZnFe2O4 on ultrathin MoS2 nanosheets were performed to enhance the photocatalytic activity and recovery property by a facile hydrothermal method. The ZnFe2O4/MoS2 photocatalysts showed a relatively high photocatalytic activity than ZnFe2O4 and MoS2 under visible light irradiation, and the degradation rate of tetracycline hydrochloride by the MoS2/ZnFe2O4-25% photocatalysts is up to 95%. Systematical characterization demonstrated that the synergistic effect of nanosheets structure of MoS2 and heterostructures formed by ZnFe2O4 and MoS2 could effectively enhance light absorption ability, increase reactive sites, inhibit recombination of the photo-generated electrons and holes, accelerate the photo-generated electrons transfer speed, and improve photocatalytic performance of the photocatalysts. The ZnFe2O4/MoS2 photocatalysts could be recovered quickly under the external magnetic field and reused four times with no significant decrease in photocatalytic activity. The ·O2− is the main active species.

In recent years, with the emergence of various kinds of drug-resistant bacteria, existing antibiotics have become inefficient in killing these bacteria, and the formation of biofilms has further weakened the therapeutic effect. More problematically, the massive use and abuse of antibiotics have caused severe side effects. Thus, the development of ultra-efficient and safe antibacterial systems is urgently needed. Herein, a photodynamic therapy (PDT)-driven CO-controlled delivery system (Ce6&CO@FADP) is developed for synergistic antibacterial and ablation biofilms. Ce6&CO@FADP is constructed using a fluorinated amphiphilic dendritic peptide (FADP) and physically loaded with Ce6 and CORM-401. After efficiently entering the bacteria, Ce6&CO@FADP can rapidly release CO intracellularly by the massive consumption of the H2O2 generated during the PDT process, without affecting the generation of singlet oxygen (1O2). As such, the combination of CO and 1O2 exerts notable synergistic antibacterial and biofilm ablation effects both in vitro and in vivo (including subcutaneous bacterial infection and biofilm catheter models) experiments. More importantly, all biosafety assessments suggest the good biocompatibility of Ce6&CO@FADP. Together, these results reveal that Ce6&CO@FADP is an efficient and safe antibacterial system, which has essential application prospects for the treatment of bacterial infections and ablation of biofilms in vivo.

Synergistic optimization of donor-acceptor blend morphologyis a hurdle in the path of realizing efficient non-fullerene small-molecule organic solar cells (NFSM-OSCs) due to the anisotropic conjugated backbones of both donor and acceptor. Therefore, developing a facile molecular design strategy to effectively regulate the crystalline properties of photoactive materials, and thus, enable the optimization of blend morphology is of vital importance. In this study, a new donor molecule B1, comprising phenyl-substituted benzodithiophene (BDT) central unit, exhibits strong interaction with the non-fullerene acceptor BO-4Cl in comparison with its corresponding thiophene-substituted BDT-based material, BTR. As a result, the B1 is affected and induced from an edge-on to a face-on orientation by the acceptor, while the BTR and the acceptor behave individually for the similar molecular orientation in pristine and blend films according to grazing incidence wide angle X-ray scattering results. It means the donor-acceptor blend morphology is synergistically optimized in the B1 system, and the B1:BO-4Cl-based devices achieve an outstanding power conversion efficiency (PCE) of 15.3%, further certified to be 15.1% by the National Institute of Metrology, China. Our results demonstrate a simple and effective strategy to improve the crystalline properties of the donor molecule as well as synergistically optimize the morphology of the all-small-molecule system, leading to the high-performance NFSM-OSCs.

Maize (Zea mays L.) stands prominently as one of the major cereal crops in China as well as in the rest of the world. Therefore, predicting the growth and yield of maize for large areas through yield components under high-yielding environments will help in understanding the process of yield formation and yield potential under different environmental conditions. This accurate early assessment of yield requires accuracy in the formation process of yield components as well. In order to formulate the quantitative design for high yields of maize in China, yield performance parameters of quantitative design for high grain yields were evaluated in this study, by utilizing the yield performance equation with normalization of planting density. Planting density was evaluated by parameters including the maximum leaf area index and the maximum leaf area per plant. Results showed that the variation of the maximum leaf area per plant with varying plant density conformed to the Reciprocal Model, which proved to have excellent prediction with root mean square error (RMSE) value of 5.95%. Yield model estimation depicted that the best optimal maximum leaf area per plant was 0.63 times the potential maximum leaf area per plant of hybrids. Yield performance parameters for different yield levels were quantitatively designed based on the yield performance equation. Through validation of the yield performance model by simulating high yields of spring maize in the Inner Mongolia Autonomous Region and Jilin Province, China, and summer maize in Shandong Province, the yield performance equation showed excellent prediction with the satisfactory mean RMSE value (7.72%) of all the parameters. The present study provides theoretical support for the formulation of quantitative design for sustainable high yield of maize in China, through consideration of planting density normalization in the yield prediction process, providing there is no water and nutrient limitation.

Lithium metal anode is a promising electrode with high theoretical specific capacity and low electrode potential. However, its unstable interface and low Coulombic efficiency, resulting from the dendritic growth of lithium, limits its commercial application. PIM-1 (PIM: polymer of intrinsic microporosity), which is a polymer with abundant micropores, exhibits high rigidity and flexibility with contorted spiro-centers in the backbone, and is an ideal candidate for artificial solid electrolyte interphases (SEI). In this work, a PIM-1 membrane was synthesized and fabricated as a protective membrane on the surface of an electrode to facilitate the uniform flux of Li ions and act as a stable interface for the lithium plating/stripping process. Nodule-like lithium with rounded edges was observed under the PIM-1 membrane. The Li@PIM-1 electrode delivered a high average Coulombic efficiency (99.7%), excellent cyclability (80% capacity retention rate after 600 cycles at 1 C), and superior rate capability (125.3 mAh g −1 at 10 C). Electrochemical impedance spectrum (EIS) showed that the PIM-1 membrane could lower the diffusion rate of Li + significantly and change the rate-determining step from charge transfer to Li + diffusion. Thus, the PIM-1 membrane is proven to act as an artificial SEI to facilitate uniform and stable deposition of lithium, in favor of obtaining a compact and dense Li-plating pattern. This work extends the application of PIMs in the field of lithium batteries and provides ideas for the construction of artificial SEI.