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Defect engineering is an effective strategy for modifying the energy storage materials to improve their electrochemical performance. However, the impact of oxygen defect and its content on the electrochemical performances in the burgeoning aqueous NH4+ storage field remains explored. Therefore, for the first time in this work, an oxygen-defective ammonium vanadate [(NH4)2V10O25·8H2O, denoted as Od-NHVO] with a novel 3D porous flower-like architecture was achieved via the reduction of thiourea in a mild reaction condition, which is a facile method that can realize the intention to regulate the oxygen defect content, with the capability of mass-production. The as-prepared OdM-NHVO with moderate oxygen defect content can deliver a stable specific capacitance output (505 F g−1, 252 mAh g−1 at 0.5 A g−1 with ∼80% capacitance retention after 10,000 cycles), which benefits from extra active sites, unimpeded NH4+-migration path and relatively high structure integrity. In contrast, low oxygen defect content will lead to the torpid electrochemical reaction kinetics while too high content of it will reduce the charge-storage capability and induce structural disintegration. The superior NH4+-storage behavior is achieved with the reversible intercalation/de-intercalation process of NH4+ accompanied by forming/breaking of hydrogen bond. As expected, the assembled flexible OdM-NHVO//PTCDI quasi-solid-state hybrid supercapacitor (FQSS HSC) also exhibits high areal capacitance, energy density and reliable flexibility. This work provides a new avenue for developing materials with oxygen-deficient structure for application in various aqueous non-metal cation storage systems.

Ti/Al/Ti laminated composite material is an ideal material for high-temperature parts and protective armor in the aerospace field because of its high specific strength and high temperature oxidation resistance. To improve the joint strength, the ultrasonic welding solid-phase joining technology is used to prepare Ti/Al/Ti laminated composites. The results show that the temperature, microstructure and microhardness distribution of the aluminum interlayer are uniform after welding. The recovery recrystallization behavior reduces the hardness of the aluminum interlayer during welding, while the microstructure and microhardness of the upper and lower titanium layers do not change significantly. The tensile shear failure positions of the joints are all located in the lower Al/Ti interface layer, and the highest tensile shear strength reaches 124.4 MPa (1200 W). At this parameter, the plastic constraint reinforcement effect is the most significant, the interface exhibits a small amount of vortex-like morphology, and the local area of the aluminum material melts below the equilibrium melting point. When the welding power reaches 1400 W, the upper surface of the weld is crushed, and the TiAl2 IMC phase precipitates in the Ti/Al interface region.

As the cleanest energy source, hydrogen energy is regarded as the most promising fuel. Water electrolysis, as the primary means of hydrogen production, has constantly been the focus of attention in the energy conversion field. Developing eco-friendly, cheap, safe and efficient catalysts for electrochemical water splitting (EWS) is the key challenge. Herein, the intermetallic silicide alloy is first synthesized via a facile magnesiothermic reduction and employed as bifunctional electrocatalysts for EWS. Ferric-nickel silicide (denoted as FeNiSi) alloy is designed and shows a good electrocatalytic performance for EWS. The lattice distortions of FeNiSi enhance the electrocatalytic activity. Besides, the porous structure affords more active sites and improves the reaction kinetics. As a consequence, FeNiSi delivers an excellent performance with overpotential of 308 mV for oxygen evolution reaction (OER) and 386 mV for hydrogen evolution reaction (HER) at 10 mA·cm−2 in 1 M KOH. The stability structure of intermetallic silicide achieves an outstanding durability with an unchanged potential of 1.66 V for overall water splitting at 10 mA·cm−2 for 15 h. This work not only provides a facile method for the synthesis of intermetallic silicide with considerable porous structures, but also develops the potential of intermetallic silicide alloy as bifunctional electrocatalysts for EWS, which opens up a new avenue for the design and application of intermetallic silicide alloy.

Rational design of oxygen evolution reaction (OER) catalysts at low cost would greatly benefit the economy. Taking advantage of earth-abundant elements Si, Co and Ni, we produce a unique-structure where cobalt-nickel silicate hydroxide [Co2.5Ni0.5Si2O5(OH)4] is vertically grown on a reduced graphene oxide (rGO) support (CNS@rGO). This is developed as a low-cost and prospective OER catalyst. Compared to cobalt or nickel silicate hydroxide@rGO (CS@rGO and NS@rGO, respectively) nanoarrays, the bimetal CNS@rGO nanoarray exhibits impressive OER performance with an overpotential of 307 ​mV@10 ​mA ​cm−2. This value is higher than that of CS@rGO and NS@rGO. The CNS@rGO nanoarray has an overpotential of 446 ​mV@100 ​mA ​cm−2, about 1.4 times that of the commercial RuO2 electrocatalyst. The achieved OER activity is superior to the state-of-the-art metal oxides/hydroxides and their derivatives. The vertically grown nanostructure and optimized metal-support electronic interactions play an indispensable role for OER performance improvement, including a fast electron transfer pathway, short proton/electron diffusion distance, more active metal centers, as well as optimized dual-atomic electron density. Taking advantage of interlay chemical regulation and the in-situ growth method, the advanced-structural CNS@rGO nanoarrays provide a new horizon to the rational and flexible design of efficient and promising OER electrocatalysts.

Layered materials with adjustable framework, as the most potential cathode materials for aqueous rechargeable zinc ion batterie, have high capacity, permit of rapid ion diffusion, and charge transfer channels. Previous studies have widely investigated their preparation and storage mechanism, but the intrinsic relationship between the structural design of layered cathode materials and electrochemical performance has not been well established. In this work, based on the first principles calculations and experiments, a crucial strategy of pre-intercalated metal-ions in vanadium oxide interlayer with administrable p-band center (ɛp) of O is explored to enhance Zn2+ storage. This regulation of the degree of covalent bond and the average charge of O atoms varies the binding energy between Zn2+ and O, thus affecting the intercalation/de-intercalation of Zn2+. The present study demonstrates that ɛp of O can be used as an important indicator to boost Zn2+ storage, which provides a new concept toward the controlled design and application of layered materials.

Abstract Aqueous zinc‐ion batteries (ZIBs) are regarded as among the most promising candidates for large‐scale grid energy storage, owing to their high safety, low costs, and environmental friendliness. Over the past decade, vanadium oxides, which are exemplified by V2O5, have been widely developed as a class of cathode materials for ZIBs, where the relatively high theoretical capacity and structural stability are among the main considerations. However, there are considerable challenges in the construction of vanadium‐based ZIBs with high capacity, long lifespan, and excellent rate performance. Simple widenings of the interlayer spacing in the layered vanadium oxides by pre‐intercalations appear to have reached their limitations in improving the energy density and other key performance parameters of ZIBs, although various metal ions (Na+, Ca2+, and Al3+) and even organic cations/groups have been explored. Herein, we discuss the advances made more recently, and also the challenges faced by the high‐performance vanadium oxides (V2O5‐based) cathodes, where there are several strategies to improve their electrochemical performance ranging from the new structural designs down to sub‐nano‐scopic/molecular/atomic levels, including cation pre‐intercalation, structural water optimization, and defect engineering, to macroscopic structural modifications. The key principles for an optimal structural design of the V2O5‐based cathode materials for high energy density and fast‐charging aqueous ZIBs are examined, aiming at paving the way for developing energy storage designed for those large scales, high safety, and low‐cost systems.

Abstract Aqueous ammonium‐ion (NH4+) hybrid supercapacitor (AA‐HSC), as a new type of energy storage device with great potential, is in the initial stage of rapid development. Based on its special energy storage mechanism, exploiting novel NH4+‐hosting materials is still a great challenge. Herein, vanadium oxide hydration (VOH) tuned by interlayer engineering of K+/PANI co‐intercalation, named KVO/PANI, is designed for AA‐HSC. Intercalated PANI can shield interaction between NH4+ and V–O layers to some extent and enlarge interlayer space, which improves the efficiency of reversible NH4+ (de)insertion. However, K+ enhances redox activity and electronic conductivity. The synergistic effect of co‐intercalation optimizes intercalation pseudocapacitive behavior during the (de)ammonization process, which is reported in NH4+ storage for the first time. Theoretical calculations reveal that the lowered electron transport barrier and enhanced electronic conductivity improve NH4+ kinetics and exhibit high capacitance for charge storage. The KVO/PANI can deliver the specific capacitance of 340 F g−1 at 0.5 A g−1 and retain 177 F g−1 at 10 A g−1. Pairing with activated carbon, the AA‐HSC can achieve a decent energy density of 31.8 Wh kg−1. This work gives inorganic/organic co‐intercalation that can enhance the NH4+ storage of VOH by interlayer engineering. The strategy can be used to design other materials for aqueous energy storage systems.

Over the past few years, the flexible quasi-solid-state zinc-ion hybrid supercapacitors (FQSS ZHSCs) have been found to be ideal for wearable electronics applications due to their high areal capacitance and energy density. The assembly of desirable ZHSCs devices that have promising practical applications is of high importance, whereas it is still challenging to assemble ZHSCs devices. In this study, a ZHSC that exhibited ultrahigh areal capacitance and high stability was developed by using an active carbon cloth (ACC) cathode, which could improve ionic adsorption. The as-obtained ACC cathode had an energy storage mechanism due to the electrical double-layer capacitive behavior of Zn2+, which was accompanied by the dissolution/deposition of Zn4SO4(OH)6·5H2O. The ACC//Zn@ACC ZHSC device exhibited an areal capacitance of 2437 mF cm−2 (81 F cm−3, 203 F g−1 under the mass of ACC with ∼12 mg cm−2) at 1 mA cm−2, an areal energy density of 1.354 mWh cm−2 at 1 mW cm−2, as well as high stability (with an insignificant capacitance decline after 20000 cycles), which was demonstrated to outperform the existing ZHSCs. Furthermore, the assembled flexible device still had competitive capacitance, energy density and service life when integrated into a FQSS ZHSC. When applied in practice, the device could achieve high mechanical flexibility, wearable stability and output. This study can inspire the development of the FQSS ZHSC device to satisfy the demands for wearable energy storage devices with high performance.

Abstract Recently, transition metal silicates (TMSs) have garnered significant attention as promising candidates for electrode materials in supercapacitors (SCs), especially cobalt silicate (Co2SiO4, CoSi) related materials. However, due to the poor conductivity and narrow potential range of CoSi, its electrochemical properties are not fully developed and far from desirable. Herein, to enhance the electrochemical properties of CoSi, hollow spheres of Mn‐doped CoSi (CoMnSi) were fabricated through a hydrothermal method. The dopant Mn facilitates the formation of CoMnSi hollow spheres assembled by nanosheets and these nanosheets connect with each other to form the core‐shell hollow architecture. The effect of the Mn/Co ratio on the electrochemical properties of CoSi has been investigated. CoMnSi‐2 (Mn/Co = 1/9) displays the specific capacitance of 495 F g−1 at 0.5 A g−1, surpassing to that of CoSi (279 F g−1 at 0.5 A g−1) and manganese silicate (denoted as MnSi, 38 F g−1 at 0.5 A g−1). The CoMnSi‐2//active carbon hybrid supercapacitor (CoMnSi‐2//AC HSC) achieves the specific capacitance with 181 mF cm−2 (151 F g−1) at 1 mA cm−2 and energy density with 0.644 Wh m−2 at 2 W m−2. The device displays a practical application by powering the LED lamp circuit bulb working for more than 25 min repeatedly. The performance achieved by CoMnSi is superior to some state‐of‐the‐art electrode materials of TMSs. Density functional theory calculations have provided evidence that Mn‐doping enhances the electronic conductivity and reduces the electron transport barrier of CoSi, boosting its electrochemical properties. This work supplies a strategy for tailoring structures of TMSs to enhance their electrochemical performance.

Abstract Exploring economic and high‐performance electrocatalysts to decrease the overpotential of oxygen evolution reaction (OER) and facilitate its reaction kinetics is a frontier subject in line with green energy. Herein, metal‐organic framework (MOF)‐derived Co nanoparticles@N‐doped carbon (Co NPs@N,C) is rationally designed on sandwich‐like cobalt silicate/reduced graphene oxide (Co2SiO4/rGO) support to acquire Co NPs@N,C/Co2SiO4/rGO “double‐triple‐biscuit”‐like structure as enhanced OER electrocatalysts. Co NPs@N,C on Co2SiO4/rGO support optimizes its geometric architecture and introduces new active sites. The “double‐triple‐biscuit”‐like Co NPs@N,C/Co2SiO4/rGO structure achieves excellent OER ability compared with the existing materials based on transition metal silicates (TMSs). The overpotential of 278 mV is achieved at the current density of 10 mA cm−2, and it is prominently higher than Co2SiO4/rGO support (390 mV). This excellent OER activity is rooted in its structural peculiarity, enabling efficient ion and electron transport. Co NPs@N,C are highly dispersed on the Co2SiO4/rGO support, increasing the active sites and avoiding self‐aggregation of Co NPs in the OER process. This work combines the advantages of Co2SiO4/rGO support with the triple biscuits' structure and MOF to implement the preparation of boosted Co NPs@N,C/Co2SiO4/rGO, and it opens a new avenue for designing novel architectures to promote the OER activity of TMSs.

Prior to dispatch from manufacturing facilities, seeders require rigorous performance evaluations for their seeding capabilities. Conventional manual inspection methods are notably less efficient. This study introduces a wheat seeding detection approach anchored in an enhanced YOLOv5s image-processing technique. Building upon the YOLOv5s framework, we integrated four CBAM attention mechanism modules into its model. Furthermore, the traditional upsampling technique in the neck layer was superseded by the CARAFE upsampling method. The augmented model achieved an mAP of 97.14%, illustrating its ability to elevate both the recognition precision and processing speed for wheat seeds while ensuring that the model remains lightweight. Leveraging this advanced model, we can effectively count and locate seed images, enabling the precise calculation and assessment of sowing uniformity, accuracy, and dispersion. We established a sowing test bench and conducted experiments to validate our model. The results showed that after the model was improved, the average accuracy of wheat recognition was above 97.55% under different sowing rates and travel speeds. This indicates that this method has high precision for the total number of seed particles. The sowing rate and sowing travel speed were consistent with manual measurements and did not significantly affect uniformity, accuracy, or dispersion.

The accurate condition assessment of wind turbines greatly influences the refined asset management and maintenance scheduling of wind farms. To address the challenges of existing assessment methods in selecting the reliability value and determining wind turbine status levels of being in transition, this study proposes a wind turbine condition evaluation method based on asymmetric proximity. Firstly, the state evaluation index system consisting of the wind turbine performance and output state indices is constructed, and the weighting factors are calculated comprehensively by integrating the subjective and objective weights. Then, the membership function of the index layer is established based on the set pair analysis, and the membership of the target layer is deduced by the weighted average operator. Finally, the proximity degrees between status levels and target membership degrees are calculated, and the wind turbine state is determined based on the proximity principle. Case studies demonstrate that the accuracy rate of the proposed method is up to 97%, which is 6% and 8% higher than the maximum membership principle and the reliability criterion, respectively.

Abstract Burning rate of solid propellants can be effectively improved by adding catalysts and using smaller size ammonium perchlorate (AP). Although few reports, the exploration of changing the size of AP primary particles by catalysts is of great significance for improving combustion performance. Here, taking Co‐bipy as an example, the potential advantages of such materials as AP decomposition catalysts are reported. Due to the existence of NO3− combined with oxygen rich environment provided by AP, the structural self‐transformation from micronrods to nanoparticles can be quickly realized during the heating process. More importantly, when Co‐bipy decomposes, it can play the role of “scalpel” and in situ cut AP particles. Results show that high‐temperature decomposition of Co‐bipy/AP occurs at 305.8 °C, which is 137.5 °C lower than that of pure AP. Catalytic mechanism is discussed by in situ IR and TG‐IR, CoO can effectively increase the content of reactive oxygen species and weaken the N–H bond, realizing the rapid oxidation of NH3. Eventually, the behavior of Co‐bipy cutting AP particles is tested. This interesting catalyst structure self‐transformation behavior can not only realize the influence on AP, but also perform a positive function in the combustion process of solid propellants, such as opening the adhesive AP interface.

Recently, ammonium-ion (NH4+) storage is in a booming stage in aqueous energy storage systems due to its multitudinous merits. To seek suitable electrode materials with excellent NH4+-storage is still in the exploratory stage and full of challenge. Herein, an inorganic-polymer hybrid, poly(3,4-ethylenedioxithiophene) (PEDOT) intercalated hydrated vanadium oxide (VOH), named as VOH/PEDOT, is developed to tune the structure of VOH for boosting NH4+ storage. By the intercalation of PEDOT, the interlayer space of VOH is increased from 11.5 Å to 14.2 Å, which notably facilitates the rapid transport of electrons and charges between layers and improves the electrochemical properties for NH4+ storage. The achieved performances are much better than progressive NH4+ hosting materials. In addition, the concentration of polyvinyl alcohol/ammonium chloride (PVA/NH4Cl) electrolyte exerts a great impact on the NH4+ storage in VOH/PEDOT. The VOH/PEDOT electrode delivers specific capacitance of 327 F g−1 in 1 M PVA/NH4Cl electrolyte at −0.2–1 V. Furthermore, the quasi-solid-state VOH/PEDOT//active carbon hybrid supercapacitor (QSS VOH/PEDOT//AC HSC) device is assembled for NH4+ storage, and it exhibits the capacitance of 328 mF cm−2 at 1 mA cm−2. The energy density of QSS VOH/PEDOT//AC NH4+-HSC can reach 2.9 Wh m−2 (2.6 mWh cm−3, 10.4 Wh kg−1) at 1 W m−2 (0.9 mWh cm−3, 35.7 W kg−1). This work not only proves that the PEDOT intercalation can boost the NH4+ storage capacity of vanadium oxides, but also provides a novel direction for the development of NH4+ storage materials.

With the intelligence of user equipment and the popularization of emerging applications such as unmanned driving and face recognition, more and more computationally intensive and delay-sensitive tasks have been generated. As a new network paradigm, ultra-dense networks can greatly improve user access capabilities by deploying dense base stations (BSs). Edge computing can effectively guarantee the low-latency requirements of users in ultra-dense networks. However, the heterogeneity of servers, the distributed resources, and the dynamic energy consumption of mobile devices in ultra-dense networks make it extremely difficult for users to offload and load balance among servers. This paper applies the idea of software defined network to proposes an edge collaboration architecture to achieve resource sharing and efficient offloading of tasks based on the characteristics of global perception. In particular, considering the high load of the local server and the idle resources of the remote server, the best offloading strategy for users is obtained game theory. Simulation results show that the performance is improved by about 30% compared to the traditional local processing, edge offload and local edge random offload schemes.

Under dry-hot valley climates, Conyza blinii (also known as Jin Long Dan Cao), suffers from nocturnal low-temperature stress (LTS) during winter. Here, to investigate the biological significance of terpenoid metabolism during LTS adaptation, the growth state and terpenoid content of C. blinii under different LTS were detected, and analyzed with the changes in phytohormone. When subjected to LTS, the results demonstrated that the growth activity of C. blinii was severely suppressed, while the metabolism activity was smoothly stimulated. Meanwhile, the fluctuation in phytohormone content exhibited three different physiological stages, which are considered the stress response, signal amplification, and stress adaptation. Furthermore, drastic changes occurred in the distribution and accumulation of terpenoids, such as blinin (diterpenoids from MEP) accumulating specifically in leaves and oleanolic acid (triterpenoids from MVA) accumulating evenly and globally. The gene expression of MEP and MVA signal transduction pathways also changes under LTS. In addition, a pharmacological study showed that it may be the ABA-SA crosstalk driven by the LTS signal, that balances the metabolic flux in the MVA and MEP pathways in an individual manner. In summary, this study reveals the different standpoints of ABA and SA, and provides a research foundation for the optimization of the regulation of terpenoid metabolic flux within C. blinii.

Targeting the problems of low precision and heavy workload in conventional screening of filled and unfilled grain in single-plant rice testing, a screening system for filled and unfilled grain was designed based on the coupling of the wind and gravity fields. In this study, the motion state of filled and unfilled grain in the flow field and the results of screening were analyzed and combined with aerodynamics. In order to reveal the influence law of the structural and working parameters of the screening system on the screening performance and determine the optimal parameter combination, this study conducted a quadratic regression orthogonal rotating center combination test with four factors and three levels based on the DEM–CFD coupling method. The relationship between air inlet wind speed, air cross-section shape, horizontal distance, vertical distance, and removal rate was studied. The results showed that, in a certain range, the removal rate was positively correlated with the section width of the outlet, positively correlated with the wind speed, and negatively correlated with the vertical distance and horizontal distance of the seed-drop outlet. The optimization results showed that, when the section width of the outlet was 75.44 mm, the wind speed was 8.90 m·s−1, the transverse distance was 198.78 mm, and, when the vertical distance was 34.87 mm, the screening rate of the screening system could reach 99.6%.

To solve the problems of high labor costs, a low weeding rate and a high seedling injury rate in the direct seeding of rice fields, this paper presents a reciprocating inter-row weeding machine for strip-seeded rice. The machine uses a combination of weeding wheels and weeding shovels to improve the efficiency of weeding between rice rows. Its reciprocating mechanism was designed and optimized. The simulation model of weeding teeth–paddy soil interaction was established in EDEM. The structural parameters of the weeding teeth were optimized, and the bending angle of the optimized weeding teeth was 55°. A prototype trial production and field tests were carried out. The results showed that the prototype’s inter-row weeding rate was between 80.2% and 85.3% and the seedling injury rate was between 3.5% and 5.1% when the prototype’s working speed was 1~3 km h−1. The faster the speed of the prototype, the lower the inter-row weeding rate and the higher the seedling injury rate.

Exploring the spatial structure of intangible cultural heritage (ICH) and constructing heritage corridors are conducive to the adaptive reuse of heritage and the improvement of the surviving environment, which is of great significance to the living inheritance of ICH. Guided by the concept of the heritage corridor, this study took the ICH along the Ming Great Wall as the research object. Kernel density estimation and a standard deviation ellipse analysis were used to explore the spatial structure and then combined with a suitability analysis of heritage corridors to further explore the spatial locations of corridors. A multifactor spatial superposition was carried out with the minimal cumulative resistance (MCR) method. The resistance factors, including land use type, elevation, slope, road system, river system, and the heritage corridors, were constructed. The results show that: (1) ICH along the Ming Great Wall forms a spatial pattern of “three cores and one belt”. The high-density core areas exist in Beijing and Liaoning, and the secondary core areas exist in northern Ningxia and southwestern Inner Mongolia. This results from the joint action of the natural, economic, and social environment. (2) On the whole, all kinds of ICH are distributed from southwest to northeast, among which folk art is particularly obvious. (3) The distribution trend of suitability is “high in the east and low in the west”. The high-suitability areas are mainly concentrated in the Beijing-Tianjin-Hebei and Liaoning regions, while the low-suitability areas are concentrated in Gansu, Ningxia, and northern Inner Mongolia. Finally, this study discusses the appropriate development mode of the heritage corridors of the Ming Great Wall from the macrolevel to the mesolevel.

Layered vanadium-based materials are considered to be great potential electrode materials for aqueous Zn-ion batteries (AZIBs). The improvement of the electrochemical properties of vanadium-based materials is a hot research topic but still a challenge. Herein, a composite of Zn-ion pre-intercalated V2O5·nH2O combined with reduced graphene oxide (ZnVOH/rGO) is synthesized by a facile hydrothermal method and it shows improved Zn-ion storage. ZnVOH/rGO delivers a capacity of 325 mAh·g−1 at 0.1 A·g−1, and this value can still reach 210 mAh·g−1 after 100 cycles. Additionally, it exhibits 196 mAh·g−1 and keeps 161 mAh·g−1 after 1200 cycles at 4 A·g−1. The achieved performances are much higher than that of ZnVOH and VOH. All results reveal that Zn2+ as “pillars” expands the interlayer distance of VOH and facilitates the fast kinetics, and rGO improves the electron flow. They both stabilize the structure and enhance efficient Zn2+ migration. All findings demonstrate ZnVOH/rGO’s potential as a perspective cathode material for AZIBs.

Vacuum-insulated glazing (VIG) has excellent sound and heat insulation and anti-fogging properties, having been a typical structure–function-integrated glass deep processing product. However, overlapping, vacancy and excessive spacing distance of the supporting pillars will increase the concentrated stress for the glass substrate, raising the potential risk of failure. Therefore, this study, aiming to address the high cost of sample preparation and the multiple factors affecting stress distribution, developed a multi-objective design for supporting stress. In this paper, a multi-objective optimization model was designed based on comprehensive mechanical analysis under square-distributed supporting. The critical supporting pillars radius as well as the critical spacing distance were solved and met the strength requirement. Case simulation demonstrated that a 0.2 mm or more radius and a 63 mm or less spacing distance for the supporting pillars were acceptable placement methods which conformed to the design requirements. This research will act as a theoretical reference for future studies, promoting the in-depth development of VIG and exploration of high-strength safety products.

AZ31B magnesium alloy/AA6061 aluminium alloy welded structures have been widely used in the lightweight design of automobile bodies. To improve the joint strength, the ultrasonic spot welding (USW) solid state connection method is used in this paper. The results show that at a welding energy of 1540 J, there is evidence of melting in the weld joint. As the welding energy increases, the intermetallic compounds (IMCs) grow rapidly and form a reaction layer approximately 17 μm thick. The IMCs are mainly composed of the γ-Mg17Al12+β-Mg2Al3 phase, where the β-Mg2Al3 phase hardness is as high as 6.5 GPa and shows a typical pop-in phenomenon and the average hardness of the γ-Mg17Al12 cubic structure phase is 3.4 GPa. When the welding energy reaches 1540 J, the β phase rapidly grows, and the joint performance decreases rapidly. The fracture morphology indicates a cleavage fracture and is accompanied by a large number of secondary cracks.

Fallow, a field where living plants are unplanted for a period, is continually implemented to accumulate moisture for the upcoming cultivation. However, there are less studies on the fallow strategies in one-crop-per-annum cropping system for coastal saline soils. In this study, 2-year “fallow + maize (Zea mays L.)” rotation experiments were carried out from 2016 to 2018 to assess how the mulching determine post-fallow soil moisture, salt distribution, and crop performance. Three treatments were designed, i.e., traditional cultivation without residue retention (TT), traditional tillage with total straw mulching during fallow (TT + SM), and no-till cultivation combined fallow mulching (NT + SM). After 2 years of fallow mulching with maize rotation, TT + SM reduced soil electrical conductivity (EC) and total salt of the upper 30 cm soil profile by 22.9% and 25.4% (p = 0.05), respectively, compared with the TT treatment. The results also indicate an improvement in volumetric soil water content (SWC) by 10.3%, soil organic matter (SOM) by 17.8%, and ultimately grain yield by 11.3% (p = 0.05) under the TT + SM treatment. Fallow mulching is recommended as an acceptable way to protect soil health in coastal fresh-starved or rain-fed farming practice.

In order to solve the problems of blocking the drainage ditch and reducing the soil flatness caused by soil accumulation when using compound planter with plowshare to ditch, a spiral soil separation mechanism (SSSM) is designed. The SSSM is analyzed. In order to obtain the optimal parameters of the SSSM, based on the discrete element method, the multifactor test is carried out with the embedded depth, pitch, and rotation speed of the spiral blade as the test factors and the soil separation distance and uniformity as the evaluation index. The optimal parameters are the embedded depth 49 mm, pitch 331 mm, and rotation speed of the spiral blade 318 r min−1. The field experiment is carried out with these parameters, with soil separation distance 900 mm and standard deviation of soil height 7.8 mm, which is consistent with the simulation results. No blockage of drainage ditch was found, which shows that this device can effectively solve the problem. This study can provide a reference for the design of soil separation equipment using spiral soil separation device.

In the multiple cropping regions of southern China, straw returning has become a widely practiced agronomic measure for rice cultivation. However, excessive straw often leads to a high proportion of stubble in topsoil, which prolongs the leveling time of the paddy field and delays the transplanting date for rice seedlings. In particular, scholars in this region have successively improved multiple paddy field levelers to realize excellent straw returning and subsequent land preparation synchronously, but the economic benefit from land preparation to crop harvest was less reported. Therefore, this study carried out a 2-year rice cultivation experiments to compare the effects of paddy field preparation methods on rice growth and economic benefits within the same growing duration. Three treatments were designed: traditional tillage (TT), double axis rotary tillage (DR) and multiple operations for paddy field preparation (DR + ML), with three repeats. The results showed that DR + ML treatment simplified the operation process while improving the quality of land preparation. Within the same growing duration, DR + ML treatment could reduce the paddy field preparation time and extend the growing time in the field by 5–6 days. Furthermore, in comparison to TT treatment, DR + ML showed advantages in stimulating plant development, increasing dry matter accumulation (DMA), and thereby increasing rice yield by more than 12%. The economic benefits were mainly reflected in saving operation cost of paddy field preparation and improving the output (grain yield), which can generally increase the total profit by 58%. The implementation of this study can provide a reference for a simplified high yield cultivation technique in rice-related multiple cropping systems.

Seed tape sowing technology is a kind of crop cultivation technology based on a carrier. This technology first wraps crop seeds in a kind of carrier materials and makes them into seed tape. The seed tape is then laid down in farmland with special equipment. Seed tape planting has the advantages of accurate control of hill spacing, simplification of field sowing process and helps to implement order agriculture. Seed tape manufacturing and laying equipment are the core equipment of the technology and their working reliability directly affects the advantages of seed tape planting technology. Based on the research status of seed tape planting technology and equipment, this article made comparisons between the key technologies which include the method for seed tape manufacturing, seed tape sowing, furrowing, seed tape guiding technology, etc. In this paper, the basic problems of seed tape technology that still need further study are put forward. The future development of tape sowing technology and equipment are predicted as follows: the intelligent high precision and high-speed seed tape manufacturing equipment, the large intelligent integrated seed tape planter of “land preparation-seeding tape making-sowing”, the small and medium-sized mobile walk-behind planters, the application on the agricultural landscape and the crop transplanting. This study will be helpful to promote the further development of seed tape planting technology and provide a reference for the research of tape planting technology and equipment.

The development of electrode materials for supercapacitors (SCs) is greatly desired, and this still poses an immense challenge for researchers. Cobalt silicate (Co2SiO4, denoted as CoSi) with a high theoretical capacity is deemed to be one of the sustainable electrode materials for SCs. However, its achieved electrochemical properties are still not satisfying. Herein, the phosphorus (P)-doped cobalt silicate, denoted as PCoSi, is synthesized by a calcining strategy. The PCoSi exhibits 1D nanobelts with a specific surface area of 46 m2∙g−1, and it can significantly improve the electrochemical properties of CoSi. As a supercapacitor’s (SC’s) electrode, the specific capacitance of PCoSi attains 434 F∙g−1 at 0.5 A∙g−1, which is much higher than the value of CoSi (244 F∙g−1 at 0.5 A∙g−1). The synergy between the composition and structure endows PCoSi with attractive electrochemical properties. This work provides a novel strategy to improve the electrochemical performances of transition metal silicates.

In this paper, a prediction method of the heat transfer coefficient of composite vacuum glazing (CVG) is proposed. By analyzing the heat transfer process of CVG, the theoretical calculation formula for the heat transfer coefficient of CVG is established. CVG temperature variation under the test conditions specified in the national standard is simulated using ANSYS. The CVG heat transfer coefficient is calculated by combining the theoretical formula and simulation results. The simulation results are then verified by comparison to a physical experiment. The results show that the deviations between the experimental and predicted values are ≤3.8%, verifying the accuracy of the simulation results and proving that the model can be used in engineering practice. Furthermore, the effects of different coating positions on the heat transfer performance of CVG are studied. The results show that different coating positions have a significant impact on the heat transfer coefficient of CVG. The heat transfer coefficient is shown to be lowest to highest under the following conditions: when the Low-E coatings are located on both sides of the vacuum layer (2LC-V), followed by Low-E coatings on the side of glass pane II near the vacuum layer (1LC-V), Low-E coatings located on the side of glass pane I near insulating layer (1LC-I), and finally, when there are no Low-E coatings (NLC) on the glass panes. Overall, this model is an effective and accurate analysis method of the heat transfer coefficient.

Appropriate agronomic management is vital for the soil fertility and crop output of coastal salt-affected farmlands. Cattle manure incorporation and straw mulching are targeted as effective methods that can improve soil structure and stimulate crop growth, respectively. However, the combined application of manure and straw into salt-affected soils is less documented, especially with limited water supplement. In this study, a 3-year field experiment (2016–2018) was conducted in Binhai district, Tianjin, China to evaluate the effects of traditional tillage without manure and straw mulching application (TT), cattle manure incorporation (CM), straw mulching (SM), and CM combined with SM (CM + SM) on soil physiochemical properties, maize (Zea mays L.) growth, and water use efficiency. TT represented traditional cultivation in the study area without manure and straw application, as a control. All four treatments were carried out in a randomized block design with three replicates. The results demonstrate that CM treatment relieved salinity, decrease bulk density, and thereby stimulated root development. SM also has the advantage of improving salinity via 3-year implementation. Throughout the 3-year cultivation, CM + SM crop yields increased by >14.3% and grain water use index (GWUI) improved by >14.7% in comparison to TT treatment due to the improvement in soil properties. These benefits in soil properties, crop yield, and water use are important for minimizing salt constraints and realizing regional agro-ecological values.

Current approaches to topdressing and weeding operations for rice cultivation present several disadvantages, such as poor precision, low efficiency, serious environmental pollution, and so on. This paper presents a row-controlled fertilizing–weeding machine to improve the precision of fertilizing and weeding operations and to reduce the heavy pollution associated with rice cultivation. A proportional–integral–derivative algorithm was adopted to realize accurate fertilization control, and an automatic driving system for agricultural machinery based on BeiDou navigation was used for accurate row-controlled operation. Accuracy testing and field experiments were carried out. The results show that the fertilization control system can stabilize the speed to within 0.55 s of the desired speed with a standard deviation of around 0.32 r·min−1. The row-controlled operation ensures the lateral deviation is within ± 5 cm at operating speeds below 5 km·h−1. The high uniformity and accuracy of fertilization meet agronomic requirements and rice cultivation standards, and the weeding performance is acceptable at working speeds below 5 km·h−1.

Abstract Phosphotyrosine Interaction Domain containing 1 (PID1; NYGGF4) inhibits growth of medulloblastoma, glioblastoma and atypical teratoid rhabdoid tumor cell lines. PID1 tumor mRNA levels are highly correlated with longer survival in medulloblastoma and glioma patients, suggesting their tumors may have been more sensitive to therapy. We hypothesized that PID1 sensitizes brain tumors to therapy. We found that PID1 increased the apoptosis induced by cisplatin and etoposide in medulloblastoma and glioblastoma cell lines. PID1 siRNA diminished cisplatin-induced apoptosis, suggesting that PID1 is required for cisplatin-induced apoptosis. Etoposide and cisplatin increased NFκB promoter reporter activity and etoposide induced nuclear translocation of NFκB. Etoposide also increased PID1 promoter reporter activity, PID1 mRNA, and PID1 protein, which were diminished by NFκB inhibitors JSH-23 and Bay117082. However, while cisplatin increased PID1 mRNA, it decreased PID1 protein. This decrease in PID1 protein was mitigated by the proteasome inhibitor, bortezomib, suggesting that cisplatin induced proteasome dependent degradation of PID1. These data demonstrate for the first time that etoposide- and cisplatin-induced apoptosis in medulloblastoma and glioblastoma cell lines is mediated in part by PID1, involves NFκB, and may be regulated by proteasomal degradation. This suggests that PID1 may contribute to responsiveness to chemotherapy.

The performance of tempered vacuum glazing (TVG) strongly depends on the structural parameters and degree of damage of the products. In this paper, attention was paid to six performance indicators which had a major influence on the damage of TVG, and new evaluation parameters were derived from them using principal component analysis (PCA). In particular, hierarchical clustering analysis (HCA) based on Euclidean distance measurement enabled TVG products to be classified into three kinds. Considering the results of PCA, product quality classification was established according to the degree of damage. The evaluation method proposed in this work was found to be simple and reliable to provide references for damage detection of TVG.

Salt accumulation in topsoil is a widespread restricting factor that limits agricultural production and threatens food security in arid and semi-arid regions. However, whether this upward enrichment was suppressed by macropores was less documented. Therefore, artificial macropores with sandy fillings (AMSF) method was proposed in this study. Soil column experiments showed a significant improvement of saturated hydraulic conductivity (Ks) by more than 260% under artificial macropore treatment. Freshwater irrigation was conducted to monitor the short-term water and salt movement. This research aimed at evaluating the potential benefit of AMSF method on soil desalinization in coastal farmland of northern China. The results demonstrated that downward movement of soil water was stimulated in AMSF method, accordingly, washing more salt ions out of top rooting zone. Particularly, 10 cm or more macropore depth treatments of AMSF method enhanced total desalinization by 52.1% to 176.6% in 0–30 cm soil layer, in comparison to the control group without macropore. Subsequent observations for alfalfa showed higher biomass by 20.8% under 15 cm macropore depth. The results here provided an exploration demonstration to pursue these studies with the ultimate goal of optimizing application strategies for amendment in coastal salt-affected lands of northern China.

Using formaldehyde and urea as raw materials, a stable urea–formaldehyde resin (UF) is synthesized by the “alkali-acid-alkali” method. Unlike most thermosetting resins, UF often shows the appearance of crystal domains. In order to understand the relationship between the crystal and morphology of UF resin, analysis was carried out with the help of polarizing microscopy (POM), scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). The changes of two kinds of UF resins with molar ratios (F/U) of 1.4 and 1.0 before and after curing and under the influence of different curing agents and additives were studied. SEM results showed that the UF resins with low F/U (1.0) show spherical or flat structures before and after curing, and the diameter of the spherical structure increases with the increase of the content of curing agent, while in the UF resin with high F/U (1.4) it is difficult to observe the above phenomenon. At the same time, the possible accumulation mode of UF colloidal particles in the process of aggregation is explained, and the curing agent obviously promotes the development of the crystal structure, which may be the reason for the emergence of a large number of spherical particles. XRD results showed that the resin with low F/U has higher crystallinity than the resin with high F/U, indicating that the former shows more crystallization regions, while the latter shows more amorphous structure, and the crystallinity increases with the increase of the curing agent content, but the position of the crystallization peak does not change with the type of curing agent and the amount of curing agent. Observation of the selected area electron diffraction (SAED) pattern obtained by TEM shows that the cured low F/U (1.0) resin has a polycrystalline structure and a body-centered cubic unit cell. FT-IR results showed that the linear segment, branched structure, hydroxymethyl and methylene structure changes in UF affect the formation of crystal structure. This study also shows the possible contribution of hydroxymethylated species to the formation of crystals.

Three-dimensional metal waveguide components are key components in the next generation of radio telescopes. Ultrasonic additive manufacturing technology combining ultrasonic welding and micro electrical discharge machining (micro-EDM) provides a new method for the overall manufacturing of waveguide elements, and the effective welding of Electrolytic Tough Pitch copper (Cu-ETP) sheets is the key process of this method. This study demonstrates that the orthogonal test optimization method is used to conduct ultrasonic welding tests on Cu-ETP. Specifically, electron backscattered diffraction (EBSD) technology is used to analyze the crystal grains, grain boundary types and texture changes during interface recrystallization. In addition, the finite element software ABAQUS 6.13 is employed to calculate the temperature field in order to determine the possibility of recrystallization of the welding interface. The results showed that the average grain size of the welding interface decreased from 20 to 1~2 μm. The Cu-ETP matrix is mainly composed of coarse grains with high-angle grain boundaries (HAGBs), while a large number of low-angle grain boundaries (LAGBs), subcrystals and fine equiaxed grains appear in the welded joint. At the same time, discontinuous dynamic recrystallization (DDRX) occurs in the less strained area, and continuous dynamic recrystallization (CDRX) is predominant in the greater strain area. The temperature field calculation shows that the peak temperature of the welding interface exceeds the recrystallization temperature of Cu-ETP from 379.05 to 433.2 °C.

Mulching and soil water content (SWC) have a significant impact on soil erosion, and this study investigated the effect of straw mulching on water infiltration and soil loss under different initial SWC treatments in a rainfall simulation experiment conducted in northern China. Increasing initial SWC can decrease soil infiltration and increase soil loss. During an 80 mm rainfall event (80 mm·h-1 for 60 min), 8%, 12% and 16% initial SWC treatments decreased cumulative infiltration by 8.7%, 42.5% and 58.1%, and increased total sediment yield by 44, 146 and 315 g, respectively, compared to 4% initial SWC. However, in all the straw mulching treatments, there was no significant difference in stable infiltration rate between the different initial SWC treatments. For all initial SWC treatments, straw mulching of 30% or more significantly enhanced water infiltration by over 31% and reduced soil loss by over 49%, compared to the unmulched treatment. Taking into consideration the performance of no-till planters, a maize straw mulching rate of 30% to 60% (1400—3100 kg·hm-2) is recommended for the conservation of water and soil in northern China.

The objective of this project was to use sucrose as a partial substitute for melamine in the synthesis of sucrose–melamine-formaldehyde (SMF) resin. The SMF was synthesized in a base condition. The wet bonding strength, shelf life, and formaldehyde emission of the SMF resin were determined. Fourier transform infrared spectroscopy (FT-IR) and mass spectroscopy (MS) were employed to analyze the chemical structure of the SMF resin. The shelf life of SMF resin increased as the sucrose content increased. Also as the sucrose content increased, the wet bonding strength decreased and the formaldehyde emissions decreased. The FT-IR and MS spectra revealed the structures of sucrose, melamine, and formaldehyde in the SMF, and chemical reactions of SMF resins occurred between the three primary hydroxyl groups of sucrose and methylolmelamine. Based on the results of this study, a sucrose to melamine mole ratio of 0.4:1 was determined to be the optimal ratio for the SMF resin.

The soap-free emulsion of vinyl acetate (VAc)/butyl acrylate (BA) copolymer was prepared by a semi-continuous and pre-emulsification polymerization method, using ammonium sulfate allyloxy nonylphenoxy poly(ethyleneoxy) (10) ether (DNS-86) as a reactive emulsifier. The effects of DNS-86 on the stability of the emulsion and the properties of the latex film were investigated. The infrared spectrum, thermal stability, glass transition temperature and micromorphology of latex were also studied. The results showed that the emulsion had the best stability and the conversion rate reached a maximum of 98.46% when the DNS-86 amount was 4 wt % of the total amount of monomers. Compared with the PVAc latex synthesized with octylphenol polyoxyethylene ether (10) (OP-10), the latex prepared with DNS-86 has higher thermal stability and ionic stability, whereas the latex film has better water resistance.

Hierarchical VOOH hollow spheres with low crystallinity composed of nanoparticles were prepared by a facile and template-free method, which involved a precipitation of precursor microspheres in aqueous solution at room temperature and subsequent hydrothermal reaction. Quasi-solid-state symmetric and asymmetric supercapacitor (SSC and ASC) devices were fabricated using hierarchical VOOH hollow spheres as the electrodes, and the electrochemical properties of the VOOH//VOOH SSC device and the VOOH//AC ASC device were studied by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS). Results demonstrated that the electrochemical performance of the VOOH//AC ASC device was better than that of the VOOH//VOOH SSC device. After 3000 cycles, the specific capacitance of the VOOH//AC ASC device retains 83% of the initial capacitance, while the VOOH//VOOH SSC device retains only 7.7%. Findings in this work proved that hierarchical VOOH hollow spheres could be a promising candidate as an ideal electrode material for supercapacitor devices.

Intercalation and in situ formation of three fluorescent complexes, Al(III)-, Cr(III)- and Cu(II)-10-hydroxybenzo[h]quinolone (M-HBQ, M = Al, Cr and Cu), in the interlayer spaces of magadiite (mag) were studied by solid–solid reactions between metal ions exchanged mags (M-mag, M = Al, Cr and Cu) and HBQ. Results show that the basal spacings of the intercalated composites increase after the intercalation of HBQ into M-mags. The amount of HBQ in the intercalated compounds is different due to the amount of metal ions and the diversification of coordination ability of metal ions, and the order of the coordination ability of these three metal ions is Cu2+ > Cr3+ > Al3+. The amount of the metal cations in the interlayer of mag is enough for the in situ complex formation of M-HBQ complexes. The slight shift of the absorption and luminescence bands of the complexes suggests the different microstructures, including molecular packing of the complexes in the interlayer spaces of mags, resulting that the host–guest interactions are formed. These findings show that the intercalation and in situ formation of M-HBQ complexes (M = Al, Cr and Cu) in the interlayer space of mag are successfully achieved in the current work.

Calcein–Ca (II), Zn (II) and Al (III) complexes were successfully intercalated into interlayer surfaces of layered silicate magadiite and fluorescence properties of organic metal-chelates in the confined spaces were investigated. Structures, compositions and morphologies of the intercalated magadiites were adequately studied by tests, including X-ray diffraction, energy-dispersive X-ray spectrometer, elemental mapping, X-ray photoelectron spectroscopy, inductively coupled plasma atomic emission spectroscopy, Fourier-transform infrared spectra, ultraviolet–visible spectroscopy, thermo-gravimetric analysis, differential thermal analysis and scanning electron microscopy. Results confirmed that metal–organic chelate species were immobilized onto the silicate sheets via solid-state interaction. Basal spacings between silicate layers decreased by exchanged metal ions and increased after intercalation of calcein into the interlayer spaces of cation-exchanged magadiites. The encapsulation was obtained by a flexible solid–solid reaction, and the present reaction and products had a potential of application to industrial uses. A speculative mechanism was proposed for reaction by solid-state intercalation. Furthermore, it was found that the complexes in the interlayer space also exhibited special fluorescence properties. The significance of this current work was that it provided a possible route for synthesizing metal–organic complexes that encapsulated in phyllosilicate.

Zeolites Na-A and Na-X are important synthetic zeolites widely used for separation and adsorption in industry. It is of great significance to develop energy-efficient routines that can synthesize zeolites Na-A and Na-X from low-cost raw materials. Coal fly ash (CFA) is the major residue from the combustion of coal and biomass containing more than 85% SiO2 and Al2O3, which can readily replace the conventionally used sodium silicate and aluminate for zeolite synthesis. We used Na2CO3 to replace the expensive NaOH used for the calcination of CFA and showed that tablet compression can enhance the contact with Na2CO3 for the activation of CFA through calcination for the synthesis of zeolites Na-A and Na-X under mild conditions. We optimized the control variables for zeolite synthesis and showed that phase-pure zeolite Na-A can be synthesized with CFA at reactant molar ratio, hydrothermal reaction temperature and reaction time of 1.3Na2O: 0.6Al2O3: 1SiO2: 38H2O at 80°C for 6 h, respectively, while phase-pure zeolite Na-X can be synthesized at 2.2Na2O: 0.2Al2O3: 1SiO2: 88H2O at 100°C for 8 h, respectively. The composition, morphology, specific surface area, vibration spectrum and thermogravimetry of synthesized Na-A and Na-X were further characterized.

This paper focuses on the problem of tracking control for vehicle lateral dynamic systems and designs an adaptive robust controller (ARC) based on backstepping technology to improve vehicle handling and stability, in the presence of parameter uncertainties and external nonlinearities. The main target of controller design has two aspects: the first target is to control the sideslip angle as small as possible, and the second one is to keep the real yaw rate tracking the desired yaw rate. In order to compromise the two indexes, the desired sideslip angle is planned as a new reference signal, instead of the ideal “zero.” As a result, the designed controller not only accomplishes the control purposes mentioned above, but also effectively attenuates both the changes of vehicle mass and the variations of cornering stiffness. In addition, to overcome the problem of “explosion of complexity” caused by backstepping method in the traditional ARC design, the dynamic surface control (DSC) technique is used to estimate the derivative of the virtual control. Finally, a nonlinear vehicle model is employed as the design example to illustrate the effectiveness of the proposed control laws.

UV-curable cyclohexanone-formaldehyde (UVCF) resin was prepared with cyclohexanone-formaldehyde (CF) resin, isophorone diisocyanate (IPDI), and pentaerythritol triacrylate (PETA) as base substance, bridging agent, and functional monomer, respectively. The structure of UVCF was characterized by Fourier transform infrared spectroscopy (FT-IR), 1H-nuclear magnetic resonance spectroscopy (1H-NMR), and gel permeation chromatography (GPC). The viscosity and photopolymerization behavior of the UV-curable formulations were studied. The thermal stability and mechanical properties of the cured films were also investigated. The results showed that UVCF resin was successfully prepared, the number of average molecular weight was about 2010, and its molecular weight distribution index was 2.8. With the increase of UVCF resin content, the viscosity of the UV-curable formulations increased. After exposure to UV irradiation for 230 s, the photopolymerization conversion of the UV-curable formulations was above 80%. Moreover, when the UVCF content was 60%, the formulations had high photopolymerization rate, and the cured UVCF films showed good thermal stability and mechanical properties.