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Abstract The high-intactness and ultraclean fabrication of suspended 2D materials has always been a challenge due to their atomically thin nature. Here, we present a universal polymer-free transfer approach for fabricating suspended 2D materials by using volatile micro-molecule cyclododecane as the transfer medium, thus ensuring the ultraclean and intact surface of suspended 2D materials. For the fabricated monolayer suspended graphene, the intactness reaches 99% for size below 10 µm and suspended size reaches 36 µm. Owing to the advantages of ultra-cleanness and large size, the thermal conductivity reaches 4914 $${\rm{W}}\,{{\rm{m}}}^{-1}{{\rm{K}}}^{-1}$$ W m − 1 K − 1 at 338 K. Moreover, this strategy can also realize efficient batch transfer of suspended graphene and is applicable for fabricating other 2D suspended materials such as MoS2. Our research not only establishes foundation for potential applications and investigations of intrinsic properties of large-area suspended 2D materials, but also accelerates the wide applications of suspended graphene grid in ultrahigh-resolution TEM characterization.

Abstract Tuning electrical properties of 2D materials through mechanical strain has predominantly focused on n‐type 2D materials like MoS2 and WS2, while p‐type 2D materials such as WSe2 remain relatively unexplored. Here, the impact of controlled mechanical strain on the electron transport characteristics of both mono and bi‐layer WSe2 is studied. Through coupling atomic force microscopy (AFM) nanoindentation techniques and conductive AFM, the ability to finely tune the electronic band structure of WSe2 is demonstrated. The research offers valuable mechanistic insights into understanding how WSe2's electronic properties respond to mechanical strain, a critical prerequisite for the development of flexible photoelectronic devices. It is also observed that under high pressure, the AFM tip/monolayer WSe2/metal substrate junction transitions from Schottky to Ohmic contact, attributed to significant charge injection from the substrate to the WSe2. These findings are significant for designing efficient metal/semiconductor contact in thin and flexible PMOS (p‐type Metal–Oxide–Semiconductor) devices.

Abstract Spintronic device is the fundamental platform for spin-related academic and practical studies. However, conventional techniques with energetic deposition or boorish transfer of ferromagnetic metal inevitably introduce uncontrollable damage and undesired contamination in various spin-transport-channel materials, leading to partially attenuated and widely distributed spintronic device performances. These issues will eventually confuse the conclusions of academic studies and limit the practical applications of spintronics. Here we propose a polymer-assistant strain-restricted transfer technique that allows perfectly transferring the pre-patterned ferromagnetic electrodes onto channel materials without any damage and change on the properties of magnetism, interface, and channel. This technique is found productive for pursuing superior-quality spintronic devices with high controllability and reproducibility. It can also apply to various-kind (organic, inorganic, organic-inorganic hybrid, or carbon-based) and diverse-morphology (smooth, rough, even discontinuous) channel materials. This technique can be very useful for reliable device construction and will facilitate the technological transition of spintronic study.

Mining activities in coal mining areas have exacerbated ecological and geological environmental risks. To explore the impact of mineral resources on the ecological and geological environment risk (EGER) in coal mining areas, we developed a novel ecological and geological risk assessment framework. This framework first quantifies the impact of mining activities on the surface of coal mining areas using remote sensing interpretation and Differential Interferometric Synthetic Aperture Radar (DInSAR) technology. Then, this framework selected six indicators, including subsidence, surface occupation and damage, FVC, RSEI, precipitation, and temperatures. The weights of the evaluation indicators were calculated using a coupled weighting model combining the Analytic Hierarchy Process (AHP) and the Entropy Method (EM). This approach was applied to the Wangwa mining area to assess its ecological and geological risks. The results show that the surface subsidence increase year by year. The EGER in the study area was medium and the change rate of the EGER index in Wangwa mining area from 2017 to 2022 was −0.460 to 0.598. The EGER index increased southwest of the study area but reduced in the pre-investigation area and north of the investigation area. This study can support decision-making to reduce the adverse environmental impact of coal mining activities.

Background: MicroRNA-216a-5p (miR-216a-5p) mediates inflammatory responses and neuronal injury to participate in the pathology of spinal cord injury (SCI). This study intended to explore the engagement of bone marrow mesenchymal stem cell exosomes (BMSC-Exo)-derived miR-216a-5p in locomotor performance, neuronal injury, and microglia-mediated inflammation in SCI rats.Methods: Rat BMSC or BMSC-Exo was injected into SCI rats. GW4869 treatment was adopted to suppress the exosome secretion from BMSC. Subsequently, miR-216a-5p-overexpressed BMSC-Exo (BMSC-miR-Exo) or negative-control-overexpressed BMSC-Exo (BMSC-NC-Exo) were injected into SCI rats.Results: The injection of BMSC or BMSC-Exo enhanced locomotor performance reflected by Basso, Beattie & Bresnahan score (p < 0.001), and neuronal viability reflected by NeuN+ cells (p < 0.01), but attenuated neuronal apoptosis reflected by TUNEL positive rate, cleaved-caspase-3 expression, and B-cell leukemia/lymphoma-2 expression (p < 0.05). Additionally, the injection of BMSC or BMSC-Exo suppressed microglia M1 polarization-mediated inflammation reflected by IBA1+iNOS+ cells, tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 (p < 0.01). Notably, the effect of BMSC on the above functions was retarded by the GW4869 treatment (most p < 0.05). Subsequently, the injection of BMSC-miR-Exo further improved locomotor performance (p < 0.05), while inhibiting neuronal apoptosis (p < 0.05) and microglia M1 polarization-mediated inflammation (p < 0.05) compared to BMSC-NC-Exo. Interestingly, the injection of BMSC-miR-Exo reduced toll-like receptor 4 (TLR4) (p < 0.01), myeloid differentiation factor 88 (p < 0.05), and nuclear factor kappa B (NF-κB) (p < 0.05) expressions versus BMSC-NC-Exo.Conclusion: BMSC-Exo-derived miR-216a-5p enhances functional recovery by attenuating neuronal injury and microglia-mediated inflammation in SCI, which may be attributable to its inhibition of the TLR4/NF-κB pathway.

Ningdong coal base area located in northwestern China is one of the largest coal-producing bases in China. The aim of this work is to investigate a regional-scale mining subsidence over the Ningdong coal base area, by using both conventional and advanced Differential Synthetic Aperture Radar Interferometry (DInSAR) methods. Fifteen L-band SAR images from ALOS-2 satellite and 102 C-band images from Sentinel-1A satellite spanning between November 2014 and July 2019 were used for the analysis. To increase the spatial extent of the displacement signal because of decorrelated effects, we modified the traditional Small Baseline Subset (SBAS) method to incorporate the coherence into the inverse problem, hereafter we call it coherence-based SBAS method. Instead of excluding decorrelated pixels present in the interferograms, we keep all the pixels in the time series analysis and down-weighted the decorrelated pixels with coherence. We performed the coherence-based SBAS method to both the two SAR datasets to obtain the subsidence rate maps and displacement time-series over the mining areas, and compared the results with that from the traditional stacking InSAR method. We evaluated the effectiveness of L-band and C-band DInSAR for monitoring mining subsidence by comparing differential interferograms and displacements derived from SBAS method between ALOS-2 and Sentinel-1A data. Compared to C-band, L-band SAR are less affected by phase aliasing due to large displacement gradients. The most significant subsidence was found at Maliantai mine with −264 mm/year detected by SBAS method from Sentinel-1 data. We validated the InSAR displacement accuracy by comparing both ALOS-2 and Sentinel-1 results with 18 GPS stations above five active mining regions. The average RMSE between InSAR and GPS measurements is 28.4 mm for Sentinel-1 data and 21 mm for ALOS-2 data. Our results demonstrate that the combined exploitation of L-band and C-band SAR data through both conventional and advanced DInSAR methods could be crucial to monitor ground subsidence in mining areas, which provides insights into subsidence dynamics and determine the characteristic surface response to longwall advance.

Nuclear factor Y (NF-Y) genes play important roles in many biological processes, such as leaf growth, nitrogen nutrition, and drought resistance. However, the biological functions of these transcription factor family members have not been systematically analyzed in maize. In the present study, a total of 52 ZmNF-Y genes were identified and classified into three groups in the maize genome. An analysis of the evolutionary relationship, gene structure, and conserved motifs of these genes supports the evolutionary conservation of NF-Y family genes in maize. The tissue expression profiles based on RNA-seq data showed that all genes apart from ZmNF-Y16, ZmNF-YC15, and ZmNF-YC17 were expressed in different maize tissues. A weighted correlation network analysis was conducted and a gene co expression network method was used to analyze the transcriptome sequencing results; six core genes responding to drought and rewatering were identified. A real time fluorescence quantitative analysis showed that these six genes responded to high temperature, drought, high salt, and abscisic acid (ABA) treatments, and subsequent restoration to normal levels. ZmNF-YC12 was highly induced by drought and rewatering treatments. The ZmNF-YC12 protein was localized in the nucleus, and the Gal4-LexA/UAS system and a transactivation analysis demonstrated that ZmNF-YC12 in maize (Zea mays L.) is a transcriptional activator that regulates drought resistance and recovery ability. Silencing ZmNF-YC12 reduced net photosynthesis, chlorophyll content, antioxidant (superoxide dismutase, catalase, peroxidase and ascorbate peroxidase) system activation, and soluble protein and proline contents; it increased the malondialdehyde content, the relative water content, and the water loss rate, which weakened drought resistance and the recoverability of maize. These results provide insights into understanding the evolution of ZmNF-Y family genes in maize and their potential roles in genetic improvement. Our work provides a foundation for subsequent functional studies of the NF-Y gene family and provides deep insights into the role of the ZmNF-YC12 regulatory network in controlling drought resistance and the recoverability of maize.

Populus euphratica, at Tarim Nature Reserve, growing in their natural habitat represents a valuable resource for the surface vegetation on the response mechanism to underground water level. In order to study the distribution of the groundwater level in Aeolian desertification areas, aiming at the current situation of groundwater dynamic online monitoring in Aeolian desertification areas, the network was effectively used to simplify data processing, increase the function of forecast and warning and optimize the power supply system. The results show that the equipment installed in Aeolian desertification areas has completed the remote transmission of data and data analysis. Based on the 25d real-time monitoring data, the groundwater level fluctuates between 0.604 and 1.515 m. Based on the table of groundwater level threshold of populus euphratica growth, the groundwater level at this location is between 0.50 and 4.71 m, and has not crossed the threshold of good growth and stress. Therefore, populus euphratica is growing well, and the equipment does not produce early warning information. Field investigation shows that populus euphratica grows well in this area, and there are many new seedlings germination, which is consistent with the data. Thus, the groundwater monitoring system can be used for dynamic monitoring of groundwater level in Aeolian desertification areas.

Accurate investigation of shale pores is critical to the assessment of shale-gas reservoir properties. Qualitative and quantitative methods have been commonly conducted in shale pore studies. In this study, we take the black shale from the Upper Ordovician and Lower Silurian black shale in the Southern Sichuan Basin as an example. Both qualitative and quantitative methods were used to study the pores at multiple scales, and we discuss the effectiveness of shale pore detection by multiple methods. The following results were obtained: 1) The black shale is composed of quartz, feldsaper, calcite, dolomite and clay minerals in the study area, and its average TOC and porosity are 2.19 and 2.12%, respectively. 2) The CT results show that the pore size of macropores (pore size >0.5 μm) mainly ranges from 2 to 16 μm. Nitrogen adsorption analysis shows that organic-rich shale has abundant organic matter pores with narrow necks and wide bodies. The pores of organic-poor shale are mainly composed of mineral-associated pores with narrow slit shapes. The NMR results show that with increasing TOC, the left peak T2 relaxation times move leftwards, meaning that organic matter pores have a larger pore size than matrix pores at the mesopore scale. 3) CT data identify lamellation fractures and bed-cutting fractures, and their development is controlled by mineral type and content, TOC and laminae density. 4) The determination of segmentation thresholds in CT and transverse surface relaxivity in NMR seriously affects the accuracy of the results.

Here, the authors investigate the long-range interaction and coalescence mechanism of water and ethanol nanopockets encapsulated in twisted bilayer graphene, showing the complete recovery of moiré patterns after the motion of the contaminants.

This paper proposes a novel refractive index profile design based on few-mode fibers (FMFs) which can support 4 linear polarization (LP) modes. We first present a FMF whose core is dually assisted by a nano-hole (NH) and a high-index-ring (HIR), and then substitute the dual assistance by an innovative graded concave HIR (GC-HIR) assisted structure. Using the finite element method (FEM), the parameters of the NH-HIR and GC-HIR optical fiber are adjusted to investigate their respective minimum effective refractive index difference (minΔneff), which is 2.012 × 10−3 for the former, and 2.532 × 10−3 for the latter. Both optical fibers have a significant improvement on the crosstalk suppression effect, and the GC-HIR optical fiber is even better. The proposed GC-HIR FMF with special refractive index profile has potential application prospects in mode division multiplexing (MDM) optical fiber communication system, and can provide theoretical foundation for the design and analysis of subsequent optical fibers and key components.

Line of Sight (LOS) deformation based on Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques cannot be used in traditional probability integration method (PIM) parameter inversion. To improve the accuracy of parameter inversion, a model based on 3D deformation was proposed. The model simulates 3D deformation using PIM directly. The inverse of the Sum of the Squared Errors (SSE) of the PIM results and the measured deformation results was used as a fitting function within the GA. Reliable PIM parameters can be obtained based on this GA model. To identify the surface movement law of the Jinfeng coal mine, 6 Global Navigation Satellite System (GNSS) monitor points were established over the 011207 and 011809 working panels. Due to the limited number of points and the large distance between the points, it is not sufficient to obtain reliable PIM parameters using GNSS only. As a complement, 83 Sentinel-1A images were analyzed with small baseline subset (SBAS) DInSAR, and the LOS direction deformation was obtained. The reliable PIM parameters were calculated with the 3D inversion model based on the combination of LOS direction deformation and GNSS-monitored deformation. Then, those parameters were used to predict the coal mine deformation of panels 011207 and 011809, which demonstrated that the prediction results coincide with the measured results. The model can be used to study the laws of mining subsidence combined with DInSAR and GNSS, which can reduce the requirements of the number of GNSS points and the impact of radar decoherence. This provides a new technical approach for studying the law of surface movement in mining subsidence research.

We propose and design a novel homogeneous nanorod-assisted multi-core photonic crystal fiber (NA-PCF), and it utilizes the flexibility of photonic crystal fiber (PCF) for air-hole design, NA-PCF applied to multi-core fiber (MCF) communication system. High refractive index nanorods are introduced in the center of the seven cores which are further surrounded by a periodical arrangement of air-holes. The air-holes and the nanorods work together to greatly suppress the crosstalk (XT) between the cores. By comprehensively balancing the influence of various parameters on XT, single-mode cutoff wavelength (λcc) and the effective mode field area (Aeff), simulation results show that the NA-PCF has a Aeff of about 70.26 μm2, XT of about −50.58 dB/km, relative core multiplicity factor (RCMF) of 4.7 and λcc of 1530 nm. This designed structure targets applications in large-capacity long-distance MCF communication.

The exceptional physical properties and unique layered structure of two-dimensional (2D) materials have made this class of materials great candidates for applications in electronics, energy conversion/storage devices, nanocomposites, and multifunctional coatings, among others. At the center of this application space, mechanical properties play a vital role in materials design, manufacturing, integration and performance. The emergence of 2D materials has also sparked broad scientific inquiry, with new understanding of mechanical interactions between 2D structures and interfaces being of great interest to the community. Building on the dramatic expansion of recent research activities, here we review significant advances in the understanding of the elastic properties, in-plane failures, fatigue performance, interfacial shear/friction, and adhesion behavior of 2D materials. In this article, special emphasis is placed on some new 2D materials, novel characterization techniques and computational methods, as well as insights into deformation and failure mechanisms. A deep understanding of the intrinsic and extrinsic factors that govern 2D material mechanics is further provided, in the hopes that the community may draw design strategies for structural and interfacial engineering of 2D material systems. We end this review article with a discussion of our perspective on the state of the field and outlook on areas for future research directions.

Energy storage systems have aroused public interest because of the blooming development of intermittent renewable energy sources. Vanadium redox flow batteries (VRFBs) are the typical candidates owing to their flexible operation and good cycle durability. However, due to the usage of perfluorinated separator membranes, VRFBs suffer from both high cost and serious vanadium ions cross penetration. Herein, we fabricate a series of low-budget and high-performance blend membranes from polyvinylpyrrolidone (PVP) and cardo-poly(etherketone) (PEKC) for VFRB. A PEKC network gives the membrane excellent mechanical rigidity, while PVP endows the blend membranes with superior sulfonic acid uptake owing to the present N-heterocycle and carbonyl group in PVP, resulting in low area resistance. Meanwhile, blend membranes also display low vanadium ion permeability resulting from the electrostatic repulsion effect of protonated PVP polymer chains towards vanadium ions. Consequently, the 50%PVP-PEKC membrane has a high ionic selectivity of 1.03 × 106 S min cm−3, while that of Nafion 115 is nearly 17 times lower (6.03 × 104 S min cm−3). The VRFB equipped with 50%PVP-PEKC membrane has high coulombic efficiencies (99.3–99.7%), voltage efficiencies (84.6–67.0%) and energy efficiencies (83.9–66.8%) at current densities of 80–180 mA cm−2, and possesses excellent cycle constancy, indicating that low-cost x%PVP-PEKC blend membranes have a great application potentiality for VRFBs.

The state-of-the-arts in action recognition are suffering from three challenges: (1) How to model spatial transformations of action since it is always geometric variation over time in videos. (2) How to develop the semantic action-aware temporal features from one video with a large proportion of irrelevant frames to the labeled action class, which hurt the final performance. (3) The action recognition speed of most existing models is too slow to be applied to actual scenes. In this paper, to address these three challenges, we propose a novel CNN-based action recognition method called SAST including three important modules, which can effectively learn semantic action-aware spatial-temporal features with a faster speed. Firstly, to learn action-aware spatial features (spatial transformations), we design a weight shared 2D Deformable Convolutional network named 2DDC with deformable convolutions whose receptive fields can be adaptively adjusted according to the complex geometric structure of actions. Then, we propose a light Temporal Attention model called TA to develop the action-aware temporal features that are discriminative for the labeled action category. Finally, we apply an effective 3D network to learn the temporal context between frames for building the final video-level representation. To improve the efficiency, we only utilize the raw RGB rather than optical flow and RGB as the input to our model. Experimental results on four challenging video recognition datasets Kinetics-400, Something-Something-V1, UCF101 and HMDB51 demonstrate that our proposed method can not only achieve comparable performances but be 10× to 50× faster than most of state-of-the-art action recognition methods.

Analyzing the transcriptome of maize leaves under drought stress and rewatering conditions revealed that transcription factors were involved in this process, among which ZmbZIP33 of the ABSCISIC ACID-INSENSITIVE 5-like protein 5 family was induced to significantly up-regulated. The functional mechanism of ZmbZIP33 in Abscisic acd (ABA) signaling pathway and its response to drought stress and rewatering has not been studied yet. The present study found that ZmbZIP33 contains a DNA-binding and dimerization domain, has transcriptional activation activity, and is highly homologous to SbABI1,SitbZIP68 and OsABA1. The expression of ZmbZIP33 is strongly up-regulated by drought, high salt, high temperature, and ABA treatments. Overexpression of ZmbZIP33 remarkably increased chlorophyll content and root length after drought stress and rewatering, and, moreover, cause an accumulation of ABA content, thereby improving drought resistance and recovery ability in Arabidopsis. However, silencing the expression of ZmbZIP33 (BMV-ZmbZIP33) remarkably decreased chlorophyll content, ABA content, superoxide dismutase and peroxidase activities, and increased stomatal opening and water loss rate compared with BMV (control). It showed that silencing ZmbZIP33 lead to reduced drought resistance and recovery ability of maize. ABA sensitivity analysis found that 0.5 and 1 μmol/L treatments severely inhibited the root development of overexpression ZmbZIP33 transgenic Arabidopsis. However, the root growth of BMV was greatly inhibited for 1 and 5μmol/L ABA treatments, but not for BMV-ZmbZIP33. Subcellular localization, yeast two-hybrid and BIFC further confirmed that the core components of ABA signaling pathways ZmPYL10 and ZmPP2C7 interacted in nucleus, ZmPP2C7 and ZmSRK2E as well as ZmSRK2E and ZmbZIP33 interacted in the plasma membrane. We also found that expression levels of ZmPYL10 and ZmSRK2E in the BMV-ZmbZIP33 mutant were lower than those of BMV, while ZmPP2C7 was the opposite under drought stress and rewatering. However, expression of ZmPYL10 and ZmSRK2E in normal maize leaves were significantly up-regulated by 3–4 folds after drought and ABA treatments for 24 h, while ZmPP2C7 was down-regulated. The NCED and ZEP encoding key enzymes in ABA biosynthesis are up-regulated in overexpression ZmbZIP33 transgenic line under drought stress and rewatering conditions, but down-regulated in BMV-ZmbZIP33 mutants. Together, these findings demonstrate that ZmbZIP33 played roles in ABA biosynthesis and regulation of drought response and rewatering in Arabidopsis and maize thought an ABA-dependent signaling pathway.

The Bayueshan (BYS) tunnels are adjacent tunnels which comprise key engineering structures important for Yurong highway from Chongqing to Sichuan, China. The tunnels were established crossing over the old goafs of a coal mine. The tunnels have been damaged three times between 2014 and 2016. To evaluate the reasons for the damage, fast Lagrangian analysis of continua in three dimensions (FLAC3D) was used to simulate the underground coal-mine excavation yearly from 2012 to 2015. The simulation results show that the subsidence of the ground surface increased annually. The maximum subsidence of the left tunnel was 505 mm and that of the right tunnel was 512 mm. The excavation led to increase in the tunnels’ stress concentration. The simulations further show that uneven horizontal displacement and subsidence were the major factors in inducing tunnel construction defects. Poor geological conditions, water, and vehicle dynamic loads were also important factors that induced damage. Several engineering suggestions for ways to maintain the tunnels are given in this paper, and the research provides a reference for safety evaluation for tunnels crossing over an old goaf.

Graphene with fascinating properties has been deemed as an excellent reinforcement for cementitious composites, enabling construction materials to be smarter, stronger, and more durable. However, some challenges such as dispersion issues and high costs, hinder the direct incorporation of graphene-based reinforcement fillers into cementitious composites for industrial production. The combination of graphene with conventional fibers to reinforce cement hence appears as a more promising pathway especially towards the commercialization of graphene for cementitious materials. In this review paper, a critical and synthetical overview on recent research findings of the implementation of graphene in fiber-reinforced cementitious composites was conducted. The preparation and characterization methods of hybrid graphene-fiber fillers are first introduced. Mechanical reinforcing mechanisms are subsequently summarized, highlighting the main contribution of nucleation effect, filling effect, interfacial bonding effect, and toughening effect. The review further presents in detail the enhancements of multifunctional properties of graphene-fiber reinforced cementitious composites, involving the interfacial properties, mechanical properties, durability, electrical conductivity, and electromagnetic interference shielding. The main challenges and future prospects are finally discussed to provide constructive ideas and guidance to assist with relevant studies in future.

OSCAs are hyperosmolality-gated calcium-permeable channel proteins. In this study, two co-expression modules, which are strongly associated with maize proline content, were screened by weighted correlation network analysis, including three ZmOSCA family members. Phylogenetic and protein domain analyses revealed that 12 ZmOSCA members were classified into four classes, which all contained DUF221 domain. The promoter region contained multiple core elements responsive to abiotic stresses and hormones. Colinear analysis revealed that ZmOSCAs had diversified prior to maize divergence. Most ZmOSCAs responded positively to ABA, PEG, and NaCl treatments. ZmOSCA2.3 and ZmOSCA2.4 were up-regulated by more than 200-fold under the three stresses, and showed significant positive correlations with proline content. Yeast two-hybrid and bimolecular fluorescence complementation indicated that ZmOSCA2.3 and ZmOSCA2.4 proteins interacted with ZmEREB198. Over-expression of ZmOSCA2.4 in Arabidopsis remarkably improved drought resistance. Moreover, over-expression of ZmOSCA2.4 enhanced the expression of drought tolerance-associated genes and reduced the expression of senescence-associated genes. We also found that perhaps ZmOSCA2.4 was regulated by miR5054.The results provide a high-quality molecular resource for selecting resistant breeding, and lay a foundation for elucidating regulatory mechanism of ZmOSCA under abiotic stresses.

The basic leucine zipper (bZIP) family of transcription factors (TFs) regulate diverse phenomena during plant growth and development and are involved in stress responses and hormone signaling. However, only a few bZIPs have been functionally characterized. In this paper, 54 maize bZIP genes were screened from previously published drought and rewatering transcriptomes. These genes were divided into nine groups in a phylogenetic analysis, supported by motif and intron/exon analyses. The 54 genes were unevenly distributed on 10 chromosomes and contained 18 segmental duplications, suggesting that segmental duplication events have contributed to the expansion of the maize bZIP family. Spatio-temporal expression analyses showed that bZIP genes are widely expressed during maize development. We identified 10 core ZmbZIPs involved in protein transport, transcriptional regulation, and cellular metabolism by principal component analysis, gene co-expression network analysis, and Gene Ontology enrichment analysis. In addition, 15 potential stress-responsive ZmbZIPs were identified by expression analyses. Localization analyses showed that ZmbZIP17, -33, -42, and -45 are nuclear proteins. These results provide the basis for future functional genomic studies on bZIP TFs in maize and identify candidate genes with potential applications in breeding/genetic engineering for increased stress resistance. These data represent a high-quality molecular resource for selecting resistant breeding materials.

solve the problem of ice forming on the top of the tunnel and achieve more efficient and convenient de-icing, we designed a tunnel laser de-icing device. First, Solidworks software was used to create a 3D model of the laser de-icing device, namely the track module, the base platform, and the work platform. Then, ANSYS simulation software is used to simulate the process of laser de-icing. When the initial temperature of the icicle is -5 °C, -10 °C, -15 °C and -20 °C, the distance between the laser and icicle is 1.5 m, 2 m, 2.5 m, and 3 m, and the wind speed is 2 m/s, 3 m/s, 4 m/s and 5 m/s, respectively. The depth of 200 s of laser irradiation and the time of full penetration were simulated under three variables. It is concluded that the higher the initial temperature, the closer the distance and the smaller the wind speed, the lower the de-icing energy consumption. Finally, the experiment results are consistent with the simulation results, which further verifies the accuracy of the simulation. The laser de-icing detection device studied in this paper provides a certain theoretical basis and reference value for the application and development of intelligent de-icing equipment in tunnels. [ABSTRACT FROM AUTHOR]

A facile solution method is used for preparing large-scale uniform dumbbell-like ZnO microcrystals under mild conditions and the influence of the reactant concentration on the size and shapes of the ZnO samples are analyzed. The room-temperature photoluminescence (PL) spectrum of the dumbbell-like ZnO microcrystals have displayed a strong ultraviolet (UV) emission peak, which is originated from the radiative free-exciton recombination by the temperature-dependent PL.

At micro- and nanoscales, the gas pressure load is generally simulated by the thermal motion of gas molecules. However, the pressure load can hardly be produced or controlled accurately, because the effects of the wall thickness and the atomic weight of the gas molecules are not taken into account. In this paper, we propose a universal gas molecules model for simulating the pressure load accurately at micro- and nanoscales, named mock gas molecules model. Six scale-independent parameters are established in this model, thus the model is applicable at both micro- and nanoscales. To present the validity and accuracy of the model, the proposed model is applied into the coarse-grained molecular dynamics simulation of graphene blister, and the simulation results agree well with experimental observations from the graphene blister test, indicating that the model can produce and control the pressure load accurately. Furthermore, the model can be easily implemented into many simulators for problems about the solid-gas interaction, especially for membrane gas systems. [ABSTRACT FROM AUTHOR]

The transport properties and mechanism of the three-terminal field-effect nanowire cross junction have been systematically investigated. An interesting phenomenon, such as applied voltage bias on nanowire cross junction makes the ON/OFF current ratio of the transistor improved by over 2 orders of magnitude, has been observed. Different from the two-terminal nanowire cross junctions, the cross junction induced potential barrier in three-terminal counterparts is found to be capable to prevent the current of the top semiconductor nanowire from injecting into the bottom nanowire at off state, while to make the current of the top semiconductor nanowire contribute to the current of the bottom nanowire at on state, resulting in the current switch between on state and off state by the gate voltage modulation. [ABSTRACT FROM AUTHOR]

Yttrium-doped ZnO thin films were deposited on silica glass substrates by the sol-gel method. The structural, electrical and optical properties of yttrium-doped ZnO thin films were investigated systematically and in detail. All the thin films have a preferred (0 0 2) orientation. When compared with the electrical resistivity values of films without annealing treatment, the values of films annealed in the reducing atmosphere were decreased by about three orders of magnitude. The lowest electrical resistivity value was 6.75 x 10[?]3 O cm, which was obtained in the 0.5 at% yttrium-doped ZnO thin film annealed in nitrogen with 5% hydrogen at 500 degC. In room-temperature photoluminescence (PL) spectra, two PL emission peaks are found in the pure ZnO thin film; one is the near-band-edge (NBE) emission at 3.22 eV and the other is a green emission at about 2.38 eV. Nevertheless, the green emission is not found in the PL of the yttrium-doped ZnO thin films. The low-temperature PL spectrum of the undoped ZnO thin film at 83 K is split into well-resolved free and bound excition emission peaks in the ultraviolet region, but the NBE emission of the 5 at% yttrium-doped ZnO thin film at 83 K has only one broad emission peak. [ABSTRACT FROM AUTHOR]

Out-of-plane deformation patterns, such as buckling, wrinkling, scrolling, and folding, formed by multilayer van der Waals materials have recently seen a surge of interest. One crucial parameter governing these deformations is bending rigidity, on which significant controversy still exists despite extensive research for more than a decade. Here, we report direct measurements of bending rigidity of multilayer graphene, molybdenum disulfide (MoS2), and hexagonal boron nitride (hBN) based on pressurized bubbles. By controlling the sample thickness and bubbling deflection, we observe platelike responses of the multilayers and extract both their Young's modulus and bending rigidity following a nonlinear plate theory. The measured Young's moduli show good agreement with those reported in the literature (Egraphene>EhBN>EMoS2), but the bending rigidity follows an opposite trend, Dgraphene

Monolayer two-dimensional (2D) crystals exhibit a host of intriguing properties, but the most exciting applications may come from stacking them into multilayer structures. Interlayer and interfacial shear interactions could play a crucial role in the performance and reliability of these applications, but little is known about the key parameters controlling shear deformation across the layers and interfaces between 2D materials. Herein, we report the first measurement of the interlayer shear stress of bilayer graphene based on pressurized microscale bubble loading devices. We demonstrate continuous growth of an interlayer shear zone outside the bubble edge and extract an interlayer shear stress of 40 kPa based on a membrane analysis for bilayer graphene bubbles. Meanwhile, a much higher interfacial shear stress of 1.64 MPa was determined for monolayer graphene on a silicon oxide substrate. Our results not only provide insights into the interfacial shear responses of the thinnest structures possible, but also establish an experimental method for characterizing the fundamental interlayer shear properties of the emerging 2D materials for potential applications in multilayer systems. [ABSTRACT FROM AUTHOR]

The controllable synthesis of ZnS nanocrystals with desirable morphology and correlative structure has been carried out via the solvothermal method by simply changing the molar ratio of the reactants. The hexagonal-shaped ZnS nanosheets with a zinc-blende structure were synthesized in one step for the first time. ZnS nanorods with wurtzite structure and large ratio of length to diameter were also fabricated. We found that phase transformation is easily induced and there is a strong correlation between the morphology and structure of the ZnS nanocrystals by changing the ratio of the reactants. The photoluminescence spectra of the ZnS nanosheets and nanorods exhibit different emission bands. ZnS nanosheets show a strong emission at 534 nm while the nanorods have two emissions located at 520 and 578 nm. [ABSTRACT FROM AUTHOR]

The article discusses the study of the Graphene fatigue through van der Waals interactions. Topics discussed unclude Graphene is often in contact with other materials through weak van der Waals (vdW) interactions; and the graphene-polymer interface, which is constantly subjected to dynamic loading in applications, including flexible electronics and multifunctional coatings.

Nanoblisters such as nanobubbles and nanotents formed by two-dimensional (2D) materials have been extensively exploited for strain engineering purposes as they can produce self-sustained, nonuniform in-plane strains through out-of-plane deformation. However, deterministic measure and control of strain fields in these systems are challenging because of the atomic thinness and unconventional interface behaviors of 2D materials. Here, we experimentally characterize a simple and unified power law for the profiles of a variety of nanobubbles and nanotents formed by 2D materials such as graphene and MoS2 layers. Using membrane theory, we analytically unveil what sets the in-plane strains of these blisters regarding their shape and interface characteristics. Our analytical solutions are validated by Raman spectroscopy measured strain distributions in bulged graphene bubbles supported by strong and weak shear interfaces. We advocate that both the strain magnitudes and distributions can be tuned by 2D material-substrate interface adhesion and friction properties. [ABSTRACT FROM AUTHOR]