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Hydrogel hybrids are one of the key factors in life activities and biomimetic science; however, their development and utilization are critically impeded by their inadequate adhesive strength and intricate process. In nature, barnacles can stick to a variety of solid surfaces firmly (adhesive strength above 300 kPa) using a hydrophobic interface, which inspires us to firmly combine hydrogels and polymers through introducing an adhesive layer. By spreading a hydrophobic liquid membrane directly, tough combination of a hydrogel and a polymer substrate could be achieved after one-step polymerization. The fracture energy of the hydrogel attached to the surface of polyvinyl chloride was up to 1200 J m–2and the tensile strength reached 1.21 MPa. Furthermore, the adhesion samples with this method exhibit an antifatigue performance, having withstood large bends and twists. It should be pointed out that this approach can also be applied to a variety of complicated surfaces. This work may expand the application range of hydrogels and provides an inspiration for hydrogel adhesion.

The preference and behavioral mechanism of the feeding behavior of the woolly apple aphid, Eriosoma lanigerum(Hausmann), on Chinese apple cultivars was investigated using the electrical penetration graph (EPG) technique. Feeding of adult aphids was assessed for the four main cultivars of apple in China (Red Fuji, Ralls Genet, Starkrimson, and Jonagold) over an 8-h monitoring period, what that of fourth-instar nymphs was assessed for 8 h on Jonagold only. EPG waveforms representing the details of probing behaviors, parameters were measured for analysis. We found that at the nonphloem phase, the total duration of the nonpenetration (np) waveform and the total duration of the stylet pathway phase (the ‘C wave’) on Ralls Genet and Starkrimson were significantly longer than on Red Fuji. In addition, the phloem-feeding phase, the total duration of ‘release of saliva into the phloem’, (the E1 waveform) was significantly longer on Ralls Genet and Jonagold than on Red Fuji. The total duration of the ‘ingestion from sieve cells’ phase (the E2 waveform) on Red Fuji, meanwhile, was significantly longer than on Ralls Genet or Starkrimson. At the same time, when combined with EPG parameters, Red Fuji was found to have no obvious resistance to woolly apple aphid and to be a susceptible cultivar. This experiment also recorded the feeding waveform of fourth-instar aphid nymphs. Based on the phloem and nonphloem parameters recorded in this study, it was inferred that adult aphids are more likely than nymphs to feed on apple trees.

Photocatalysis, a revolutionary process harnessing the inexhaustible solar energy to drive chemical reactions, holds immense promise in addressing energy and environmental challenges in a sustainable manner. As a category of diversified semiconductor materials with unique structure and optoelectronic properties, perovskites have emerged as a new class of photocatalytic materials. However, they are still plagued with limitations, circulating over issues relating to instabilities. To address this, versatile and porous metal-organic frameworks (MOFs) can be combined with labile perovskites. This hybridization leverages the high light utilization of perovskites and the large surface area of MOFs, sparking significant interest in photocatalytic applications. The harmonious integration of perovskite and MOF mitigates individual shortcomings, yielding stable and highly active photocatalysts. Moreover, employing MOF hosts with diverse properties allows the incorporation of various functionalities into the composite material. This review comprehensively addresses the fundamental properties and intrinsic challenges of perovskites, followed by the introduction of MOFs as a promising solution. The synergistic benefits of hybridizing perovskites with MOFs are critically evaluated, particularly in terms of enhancing stability and photocatalytic performance, showcasing their potential to overcome existing limitations and expand practical applications. We then explore key design considerations and synthesis strategies, focusing on how they influence the resulting composite structures. The versatility of these hybrid materials is demonstrated through their current applications, ranging from pollutant degradation to energy generation. Furthermore, we address the prevailing challenges associated with perovskite/MOF composites and provide an outlook for future research, offering insights into their rational design to encourage further innovation in advanced photocatalysts. By synthesizing recent advancements, this review provides a timely overview of the field, with a particular focus on novel composite structures that have yet to be thoroughly explored in previous literature.

Understanding the genetic basis of theobromine and caffeine accumulation in the tea plant is important due to their contribution to tea flavor. Quantitative trait loci (QTL) analyses were carried out to identify genetic variants associated with theobromine and caffeine contents and ratio using a pseudo-testcross population derived from an intervarietal cross between two varieties of Camellia sinensis. A total of 10 QTL controlling caffeine content (CAF), theobromine content (TBR), sum of caffeine and theobromine (SCT), and caffeine-to-theobromine ratio (CTR) were identified over four measurement years. The major QTL controlling CAF, qCAF1, was mapped onto LG01 and validated across years, explaining an average of 20.1% of the phenotypic variance. The other QTL were detected in 1 or 2 years, and of them there were four, two, and three for TBR, SCT, and CTR, respectively. The present results provide valuable information for further fine mapping and cloning functional genes and for genetic improvement in tea plant.

Catechins are important chemical components determining the quality of tea. The catechin index (CI, ratio of dihydroxylated catechin (DIC)/trihydroxylated catechin (TRIC)) in the green leaf has a major influence on the amounts of theaflavins in black tea. In this work, the major catechin profiles of wild tea plants originating from Guizhou Province with high CI trait were investigated. We identified a novel flavonoid 3′,5′ hydroxylase gene (F3′5′H) allele with a 14 bp deletion in the upstream regulation region and developed an insertion/deletion (InDel) marker accordingly. The 14 bp deletion in the novel F3′5′Hallele was associated with low F3′5′HmRNA expression, thereby resulting in low TRIC content and high CI value. The allelic variant in the novel F3′5′Hallele associated with high CI values and DIC contents was confirmed by the introgression lines derived from a distant cross population. The novel F3′5′Hallele in wild tea plants is a valuable gene resource, which could be applied to breeding improvement on tea quality.

The effect of heat treatment on the microstructure and thermal fatigue properties were studied by means of optical microscope (OM) and scanning electron microscope (SEM). Energy dispersive X-ray detector (EDX) was used to analyze the role of phase composition in fatigue crack propagation. The results show that after heat treatment, the ultimate tensile strength increased from 285 MPa to 368 MPa and the elongation increased from 5.8 % to 6.5 %. During the initiation of fatigue crack, the crack was mainly propagated through eutectic Si area. With the long needles of eutectic Si particles spherodized after heat treatment, the split action from brittle Si particles to α-Al matrix was reduced and prolonged the fatigue crack initiation period. After aging for 6 h, the dispersed precipitation of secondary phases (Al2Cu, Mg2Si) elevated the driving force of crack propagation, blocked the spread of crack in the grain boundary, decreased the rate of fatigue crack growth and improved the fatigue resistance of alloy at the same time. In the process of crack initiation, the surplus-phase around the grain boundary fell off from α-Al matrix under thermal cycling stresses. The combination of interfaces was weaken by cycling stress and the fatigue crack was finally grown up in the weakness area between matrix and secondary phase.

Self-healing hydrogels have a great potential application in 3D printing, soft robotics, and tissue engineering. There have been a large number of successful strategies for developing hydrogels that exhibit rapid and autonomous recovery. However, developing a gel with an excellent self-healing performance within several seconds is still an enormous challenge. Here, an ultrafast self-healing hydrogel based on an agarose/PVA double network (DN) is presented. The gel utilizing a dynamic borate bond exhibits 100% cure in strength and elongation after healing for 10 s in air, and this hydrogel shows an excellent self-healing property underwater as well. In addition, the agarose/PVA DN hydrogel exhibits a smart self-healing property for an in situ priority recovery, ensuring that the shape and the function are the same as those of the original one. With the combination of self-healing properties, such a hydrogel could be applied to a board range of areas.

Being the energy glutton and top ranker of greenhouse gas emission, Haber-Bosch is undoubtedly a grand challenge to reaching sustainability and carbon neutrality. Solar-driven nitrogen (N2) fixation under mild conditions is highly attractive and promising for sustainable ammonia (NH3) production. However, low conversion efficiency remains as a serious problem yet to be solved due to the difficult activation of strongly non-polar NN bond. In this study, defective and atomically thin g-C3N4with boron sites was synthesized via a facile decomposition-thermal polymerization technique. The optimum photocatalyst displayed an NH3yield of 213.59 μmol gcat−1h−1under visible light irradiation (λ > 400 nm) without any hole scavenger, bestowing high suitability for N2fixation in pure water. The impressive performance is largely ascribed to the introduction of B species, which could act as the active sites for N2adsorption, activation and reduction. Additionally, the atomically thin layer (∼3.25 nm) shortens charge carrier transport pathway while the B atoms and defects suppress quantum size effect as well as extends photo-response through bandgap reduction. These attributes synergistically lead to suppressed electron-hole recombination, efficacious charge transport, enhanced light utilization and enriched catalytic sites for N2fixation. As a whole, this work presents an easy strategy to realize efficient N2photofixation over a metal-free, low-cost and non-toxic photocatalyst in pure water as a continuous effort in advancing the burgeoning field of photocatalytic N2fixation.

CIP/ZnO electromagnetic functional composites with core-shell structure were prepared by chemical precipitation method, and then the morphology, structure and electromagnetic properties in 2-18GHz were characterized by X-ray diffraction, scanning electron microscopy and vector network analyzer, respectively. In process by controlling the component ratio between core and shell, it has been found that the more ZnO particles were coated on the CIP surface, the smaller electromagnetic parameters become. Based with the Electromagnetic Wave Absorption (EMWA) Theory, the composites could prepare EMWA building coating by monolayer design, the theoretical simulation results show that the minimum RL of CIP/ZnO composites is-10.25dB, better than pure CIP particles, exhibiting excellent EMWA properties in 2-18GHz. The magnetic loss of CIP and the dielectric loss of ZnO were the main mechanisms of EMWA for the CIP/ZnO composites, which could be used for electromagnetic radiation protection.

This paper proposes a new method of harmonic energy measurement based on atomic decomposition algorithm. Firstly, the matching pursuits (MP) algorithm is introduced and harmonic atom dictionary is designed according to the characteristics of signals to be analyzed to improve the effect of signal decomposition. Then, the MP algorithm is optimized by particle swarm optimization (PSO) to reduce the calculation amount. The simulation results of active harmonic energy in steady and unsteady state demonstrate feasibility and accuracy of the presented method.

This paper studies electromagnetic parameters' impact of λ/4 type dielectric absorber on absorbing properties. Calculation shows that the maximum absorption amount is corresponding to specific values of K and R when absorber's permittivity is stable, when the thickness of material is determined and the real part permittivity is increased, the absorption peaks move to lower frequency and reduce the distance between adjacent peaks, while the imaginary part of permittivity and resistance of membrane resistance only affect absorption peaks' amount but have no effect on the peaks' position. Accordingly, it is reasonable to adjust the material's electromagnetic parameters according to the above rule when the high-performance λ/4 dielectric-type absorber is prepared.

The measurement of the complex permittivity of big structure composite material has always been a key and difficulty in the preparation of electromagnetic functional materials. In this paper the average dielectric constant inversion of coconut fiber/gypsum composite in S band is studied based on λ/4 absorption spectrum. First the absorbing effects of the prepared coconut fiber gypsum composite materials are tested with method of flat reflection. Then the equivalent complex permittivity is inversed with the inversion theory. Further the experimental verification is preceded that the theoretical and experimental absorbing curves whose peak positions are respectively at 3.05GHz and 2.45GHz are quite matched. And the study shows that this method is scientific and effective, and it can provide technical support for the baroque electromagnetic functional composite materials.

This paper studies the effect on absorbing property of content and length of the carbon fibers of λ/4 type absorber made of carbon fiber membrane and gypsum board. The experimental results show that absorbing property of λ/4 type absorber made of carbon fiber membrane and gypsum board firstly increases and then decreases with the increase of the content or length of the carbon fibers. The absorbing property is best while carbon fiber membrane’s length is 2mm and content is 2.8% composited with gypsum board whose thickness is 1.5cm. The maximum absorption is-27.08dB.

Using the dielectric loss property of carbon black , cement-based composites were prepared by introducing carbon black into cement. The reflection losses were studied using arched testing method in the frequency range of 2~18 GHz. The results showed that the absorption properties were improved in high frequency. The filling ratio of carbon black as well as the thickness of samples had influence on the absorption properties. The lowest reflection loss of-10.6 dB was obtained at 18 GHz of 5wt.% carbon black filled cement with thickness of 20mm. The new material can be used for building indoor electromagnetic radiation protection.

Abstract .Electromagnetic radiation affects normal operation of electronic devices and causes harm to human health, the use of electromagnetic radiation protective material, especially the electromagnetic wave absorption material, is an effective method for interference control and radiation protection, λ / 4 type dielectric absorber with a simple and practical nature, the protective layer should be added to ensure its durability in practice, this article discusses the gypsum board as the substrate, the thickness of conventional protective layer's material impacts on the absorbing properties. Studies show that: the position of absorption peak moves to lower frequency with increase of the protective layer's thickness by the theory and experiment, this paper puts forward the protective layer's thickness criterion's impact on the absorption characteristics, the thickness less than 0.05 cm has little effect on absorption characteristics in S band , which can simplify theoretical calculation and be convenient to select a material; when the thickness of the protective layer has a significant effect on absorption, the relationship among the parameters of absorber can be found according to theoretical simulation, thereby reducing or eliminating the impact of protective layer thickness on absorption characteristics.

According to the principle of electromagnetic wave absorption, functionally reforming thermal insulating materials for building, through designing and theoretically simulating of the λ/4 model, the article has successfully prepared EPS composite gypsum boards for electromagnetic wave absorption. The result shows that, a maximum absorption of-18.7dB at 3GHz and 85% of bandwidth below-10dB was achieved under following conditions: using 380Ω/□ resistive film, specimen thickness of 1.50cm. However, by using phase modulation membrane (PMM),it achieved a maximum absorption of-20dB and 100% of bandwidth below-10dB. This new composite materials can be used for electromagnetic interference protection for WLAN and indoor electromagnetic radiation pollution control.

large thickness of λ/4 type absorber has been an important issue, which affects its application and urges to address. In this paper, λ/4 Type absorber made of carbon fiber membrane, instead of resistive film, and Gypsum board. Its designed for thinning and we took Simulation analysis and experimental testing for it. Results show that, while carbon fiber membrane with a length of 2mm and content of 2.8%, λ/4 type gypsum composite absorber has better absorbing in S-band. Compared with the resistive film, absorber achieved thinning of 10.6%.

According to the principle of electromagnetic wave absorption, functionally reforming thermal insulating materials for building, through designing and theoretically simulating of the λ/4 model, using carbon fiber film, the article has successfully prepared insulation coatings for X-band electromagnetic wave absorption. Result shows, with the thickness of 3.0 mm in 8 ~ 12 GHz band, 100% of bandwidth below-10 dB can be reached. New materials can be used such as the surface of the thermal insulation of buildings and X-band electromagnetic interference protection.

CIP particles first have been coated with SiO2 shell by a Stober process , then grafted the polyaniline by in-situ polymerization to prepare CIP/SiO2/PANI core-shell composites, and the composites are composed the dielectric loss properties with the magnetic loss properties. It is observed that PANI are on the surface of CIP/SiO2 particles from the SEM image, XRD patterns further confirm that the CIP/SiO2/PANI composites are synthesized successfully. In comparison with CIP, the complex permittivity of CIP/SiO2/PANI composites have certain enhancement in 8-12 GHz frequency range, but it has a very small impact on the complex permeability. On the basis of the Electromagnetic Wave Absorbing Theory, the composites could prepare high-performance absorbing coating based on λ/4 type design, and the coating is below-10dB in the whole X-band, which could be used for architectural space electromagnetic radiation protection.

The problem of WLAN anti -interference has become an important issue that affects the application. This paper explores the electromagnetic parameters' optimization of λ/ 4 type dielectric absorber in 2.4GHz and 3.6GHz .Studies show that: through the early design of the material's parameters, such as complex permittivity and thickness, the obtained ideal electromagnetic parameters' area can achieve a predetermined reflectivity at the desired frequency , then choose material to get high absorbing preparation , which can provide design basis for the preparation of different frequency band and high performance electromagnetic wave absorber.

CIP particles first were coated with SiO2 shell by the Stober process , then grafted the polyaniline by in-situ polymerization to prepare CIP/SiO2/PANI core-shell composites. The CIP/SiO2/PANI composites are composed the dielectric loss properties with the the magnetic loss properties, the morphologystructure and electromagnetic properties are characterized by SEMXRD and vector network analyzer, respectively. It is observed that SiO2 and PANI are on the surface of CIP particles, XRD patterns further confirm that the CIP/SiO2/PANI composites are synthesized successfully, and that interaction between components exist in the polymerization. In comparison with CIP, the complex permittivity of CIP/SiO2/PANI composites have certain enhancement in 2-18GHz frequency range, but it has a very small impact on the complex permeability.

Magnetorheological Fluid Damper has recently received considerable attention. This paper is focused in typical models, the strongpoints and application status of magnetorheological damper. In the meantime, the paper introduce the basic working principle of the smart passive damper using magnetorlogical fluid damper and the Faraday law how to be used in the magnetorlogical fluid damper with the electromagnetic induction part.

In this paper, the effects of multiple aquifers on the calculation of bearing capacity of foundation are represented. One side is how to ascertain the maximal influence depth of underground water, and the other is which to take from the unit weight of soil in the condition of multiple aquifers.

Based on the principle of electromagnetic wave absorption, through the double-layer matching design and simulation analysis, taking foam cement panel as the dielectric material, combining with the resistive film, the paper has successfully prepared high-performance and broad-band foam cement absorbing panel for electromagnetic pollution control. The result shows, with the use of double-matching design that combines 140 Ω/□ resistive film with foam cement absorbing panel whose each layer thickness is 1.4 cm, in the S band , 100% of bandwidth below-10 dB and 95% of bandwidth below-14 dB can be reached, a maximum absorption of-19.6 dB at 2.45 GHz, the width of the absorption is far more than that of λ/4 type absorber. New materials can be used for the improvement of indoor electromagnetic environment and pollution control.

n order to reach high electromagnetic wave absorption property, here we developed a cement composites building materials. Special-shaped structure surfaces have been designed to make the continuity change of impedance and increase the incident times for electromagnetic wave. Different ratio of flexible glass fiber were introduced to adjust the impedance matching characteristics of the composites and to attenuate the incident wave by scattering. As the concentration of 9% glass fiber and the surface of rectangle, the reflectivity reached the highest in the absorber with 20mm thickness. the lowest reflection loss of-15.8 dB was obtained at 8.9GHz, and the effective absorption bandwidth (less than-8 dB) reached 12 GHz in the frequency range of 1.7~18 GHz. The new material can be used for building indoor electromagnetic radiation protection.

This paper reports that according to the principle of EMW-absorption, thermal insulating EMW-absorber for building was designed and theoretically simulated of the λ/4 type. The EMW-absorption properties of composites in the band of 2-4 GHz were examined, A maximum absorption of-20 dB at 3 GHz and 80% of bandwidth below-10 dB was achieved under following conditions: using 380Ω/□ resistive film, specimen thickness of 2 cm. Similarly, absorbing materials for 2.45 GHz have successfully designed and prepared,a maximum absorption of-17 dB at 2.45 GHz, and 65% of bandwidth below-10 dB can be reached. New materials can be used for electromagnetic interference protection for WLAN and indoor electromagnetic radiation pollution control.

This paper reported that, using the method of double layer composite successfully prepared high performance of electromagnetic wave absorption materials. Such a composite is composed of a cement matching layer filled with expanded polystyrene (EPS) beads and an absorbing cement layer made of EPS beads and carbon black. The samples were tested by arching method in the frequency range of 8~18GHz. The reflectivities were revealed to be excellent, the lowest being-17dB. The new material can be used for building indoor electromagnetic radiation protection.

This paper reported a new type MDF absorber of high absorption and Broadband was successfully prepared, according to the Electromagnetic Wave Absorbing Theory, by means of the theoretical design and simulation analysis by using MDF as the dielectric material and And with the resistance film composite. Results shown that the resistance of resistive film was 195Ω/□, the monolayer combined sample with thickness as 1.4cm in 2~4 GHz frequency bands, the range of absorbing over -20dB could achieve 50%, and all absorption could exceed -15dB in the whole S-band, the maximum absorption peak was -25dB, moreover, the absorption bandwidth of MDF was more than λ/4 Type EWM-absorber. The new materials could be used to improve residential electromagnetic environment and control pollution.

Most rollover accidents involve articulated engineering vehicle due to the center of gravity shift when steering. In this paper, a virtual prototype model of a loader as the typical articulated engineering vehicle is built using multi-body dynamics software. The dynamic simulation of steering characteristic under different slop and speed is made and the roll stability is analyzed. The stable working range of the loader obtained from the simulation results can give reference for the drivers selection of vehicle route and safe operation. This paper has a certain meaning for further study of articulated vehicles roll stability.