Interfacial polarization has been proved to significantly contribute to the effective absorption of electromagnetic waves (EMW). However, a model that clearly defines the contribution of interfacial polarization has yet to be developed. In this work, a layer of WO3 was introduced within the WS2/PPy nanocomposites by oxidation to create a heterojunction interface, resulting in the formation of a WS2/WO3/PPy nanocomposite material. The experiments demonstrated that interfacial engineering could significantly enhance the electromagnetic wave absorption capability of the material. The WS2/WO3/PPy composite achieved a minimum reflection loss (RLmin) of -58.87dB at a thickness of 3.3mm and an effective absorption bandwidth (EAB) of 6.72GHz at a thickness of 2.3mm. This work clarifies the impact of interfacial polarization on EMW absorption, providing a feasible approach for designing novel, high-efficiency EMW absorbing materials.

Two types of JP-3 kerosene gels were prepared using AC-C10 (N-acetyl-L-isoleucyl decylamine, type A) and modified hydrogenated castor oil (type B) as gelling agents, and the gel formation mechanism between the two gelling agents and JP-3 kerosene was investigated. The rheological properties of the gels, including stability, yield stress, shear thinning, and thixotropic behavior, were tested and discussed. The viscosity curves were fitted with the HBE constitutive equation and compared with the power-law model. Non-time-dependent, time-dependent, and temperature-dependent constitutive equations of the kerosene gels were constructed. The effects of time and temperature on viscosity were analyzed. The results showed that the type B JP-3 kerosene gel was more physically stable and less influenced by centrifugal force. Both types of gels exhibited a decrease in viscosity with increasing shear rate, indicating shear thinning behavior. Additionally, both gels demonstrated some degree of thixotropy, although the recoagulation was found to be weak. With an increase in temperature, the viscosity of the type A gel initially decreased, then increased, and finally decreased again until it approached the viscosity of kerosene at 75 degrees C. On the other hand, the viscosity of the type B kerosene gel gradually decreased and approached the viscosity of kerosene at 75 degrees C. Both types of gels exhibited high temperature sensitivity. image

Enhancing polarization loss is an effective method to improve electromagnetic wave absorption (EMA) performance. However, constructing more interfaces and inducing defects is a significant challenge in polarization regulation. This paper reports synthesizing a core-shell structure HNTs@M/C (M=Cu, Co, Zn) by pyrolysis of metal-organic frameworks (MOFs). The enhancement of conduction loss is attributed to the electronic conduction network formed by the carbon layer and the metal particles. Co nanoparticles (NPs) create more interfaces with the carbon layer, significantly boosting polarization performance. Additionally, Zn sublimation induces numerous defects in the carbon layer, leading to cumulative amplification of polarization and stronger dielectric resonances in HNTs@Zn/C. With a thickness of 2.4 mm, the HNTs@Zn/C achieve an effective absorption bandwidth (EAB) of 6.9 GHz, covering the entire Ku-band with a minimum reflection loss of -61 dB. This work provides design strategies for interfacial and point interaction of polarization regulation.

Defect modulation strategies have been shown to be an effective way to design efficient EMW absorbing materials, but the coexistence of multiple loss mechanisms due to the complexity of the existing models makes it difficult to elucidate the mechanism by which defect-induced dielectric losses dominate. In this work, p(C3O2)x is applied for the first time in the field of EMW absorption and the concentration of defects in the sample is controlled by changing the pyrolysis temperature. In addition, the unique molecular structure of p(C3O2)x enables the prepared samples to completely eliminate the interference of interfacial polarization and magnetic loss on EMW dissipation. The results show that the dielectric loss induced by defects significantly enhances the EMW absorption performance as the concentration of defects increases, but excessive defects lead to a sudden drop in the conductivity of the sample and reduce the EMW absorption performance. In which, the RLmin of OC-800 can reach -51.0 dB, and the EAB of OC-900 can go up to 5.6 GHz at only 1.6 mm. Finally, CST simulation verified the potential application of the prepared absorber in real scenarios. This work has improved the theoretical basis of the effect of defect-induced dielectric loss on EMW absorbing properties, and the simple synthetic raw materials and routes have made the industrialized production of highly efficient EMW absorbing materials possible.

Metal borides (e.g., MCoB) are widely used in the field of electrocatalysis due to their excellent electrochemical performance, but the poor dielectric loss limits their application in electromagnetic wave absorption (EMA). Thus, to improve the dielectric loss ability of metal borides, it needs to be compounded with dielectric materials. In this work, through reduction process and lyophilization process, Boride/PVP (MCoB/PVP) composites are obtained. After pyrolyzing these samples, Boride/Carbon (MCoB/C) nanocomposites are successfully synthesized. The EMA performance of nanocomposites are fine-tuned by balancing the magnetic and electric components and substituting metal elements of MCoB/C-X (M = Fe, Ni, Cu, X = 1, 2, 3). Among them, NiCoB/C-2 has the minimum reflection loss of -45.34 dB at thickness of 3.1 mm, and CuCoB/C-2 achieves an effective absorption bandwidth up to 6.92 GHz at thickness of 2.0 mm. This work proves the applicability of magneticelectric balance and ion substitution tuning strategy. It also presents a new way for the application of metal borides in the field of EMA.

Rational design and fabrication of MoO3 ceramic with controllable electronic structure is expected to deliver favorable magnetic moments, leading to excellent electromagnetic behavior. However, achieving large-scale precise modulation of the MoO3 electronic structure is still a challenge. Here, a low-temperature, high-effi-ciency nitrogen radio frequency (RF) plasma treatment method was adopted to modify the surface of MoO3 with N doping and investigate its electromagnetic wave absorption (EMA) mechanism in depth. After MoO3 powder treating with N2 plasma for 30 s, at the doping ratio is 70%, the minimum reflection loss (RLmin) is -43.35 dB and the maximum effective absorption bandwidth (EAB) could reach 6.16 GHz at a low thickness (2.1 mm). The significant improvements in dielectric loss and permeability loss of N-doped MoO3 are because the doping of N atoms reduces the bandgap of MoO3, promotes electron jumping, dramatically improves electrical conductivity of semiconductors, and introduces interfacial polarization and dipole polarization effects. The presence of magnetic moments renders the N-doped MoO3 with weak magnetic properties and significant eddy current losses. This study provides an explicit EMA mechanism for non-metal doped transition metal oxidation.

This study demonstrates the implementation of the Hamming code using DNA-based nanostructures for error detection and correction in communication systems. The designed DNA nanostructures conduct logical operations to compute check codes and identify and correct erroneous data based on fluorescence signals. The execution of intricate DNA logic operations requires individuals with specialized training. By interpretation of the fluorescence signals generated by the DNA nanostructures, binary language can be extracted, effectively protecting data security. The findings highlight the potential of DNA as a versatile platform for reliable data transmission.

Hydrogel materials are the preferred candidates for antimicrobial materials due to their high water absorption, superior biocompatibility and structural diversity. In this work, we present for the first time that diamine-alkyl and 1,3-dibromo-2-propanol can be rapidly cross-linked to prepare a series of new cationic polymer gels by polycondensation reactions under a strongly alkaline environment. The presence of CN+ bonds are demonstrated in the formation of dendritic structured polymers by XPS analysis. In addition, the physicochemical properties of b-PHIs hydrogels were evaluated and it was found that the variation of diamine alkyl chain length could modulate the storage modulus, water uptake properties, thermal stability and zeta-potential of the gels. The increase in hydroxyl content and the CN+/CC ratio is evidenced by the elevated water absorption properties of the gels and the variations in zeta potential, respectively. In addition, the antibacterial performance evaluation showed that gels had good antibacterial activity against S. aureus and E. coli, with antimicrobial rates of b-PHOI as high as 96% and 97%, respectively. This work pioneers a brand-new idea for the simple and rapid synthesis of branched cationic polymers with low cytotoxicity in the field of antimicrobial biomaterials and proceeds a new attempt in the directional modulation of the physical properties of the materials.

Bacterial infections are a common problem associated with wound treatment that imposes a significant burden on healthcare systems and patients. As a result, healthcare providers urgently need new treatment strategies to protect people. Hydrogel biomaterials with inherent antimicrobial properties offer an attractive and viable solution to this issue. Here, for the first time, we have developed a new efficient synthetic strategy to prepare cationic hydrogels (PHCI) with intrinsically efficient antimicrobial properties by chemically cross-linking trans-1,4-cyclohexanediamine with 1,3-dibromo-2-propanol using a condensation reaction without the use of toxic cross-linking agents. As expected, the prepared PHCI hydrogel possessed an inherent antibacterial ability that can adsorb and kill Staphylococcus aureus and Escherichia coli electrostatically. Notably, in vivo experiments on normal and diabetic rat models confirmed that the PHCI hydrogel can quickly stop bleeding, efficiently kill bacteria, promote the conversion of macrophages from the proinflammatory M1 phenotype to the repaired M2 phenotype, and accelerate collagen deposition and blood vessel formation, thereby achieving rapid wound healing. Overall, this work presents an effective antibacterial dressing that might provide a facile but effective approach for clinical wound management.

Three furan-based diketopyrrolopyrmle (DPP) chromophores have the same D-A-D structure and various tetraphenylethylene, pyrene and dibenzothiophene tails with intramolecular donor-acceptor spacers. Different pi-extended chromophores show different intramolecular charge transfer properties. Furthermore, according to UV-Vis and emission spectral studies, dyes F1-F3 exhibit aggregation-caused quenching (ACQ) in tetrahydrofuran aqueous solutions. Interestingly, dyes F1 and F3 show aggregation-induced emission (AIE) behaviors in DMSO/toluene mixtures, while pyrene-functionalized DPP dye F2 still has ACQ character. It is noted that a contour plot is firstly carried out to be better understood the AIE and ACQ phenomena. Moreover, the energy gaps for the methyl counterpart of dyes F1-F3 are 2.30, 2.29 and 2.35 eV, respectively, which indicate that introducing asymmetrical D-A-D-pi furan-containing DPP structures can reduce the HOMO-LUMO gaps easily and rapidly. In addition, a computational and experimental investigation has been provided, including theoretical and optical energy gaps for full comparison.