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Teknolojinin gelişmesine paralel olarak kablosuz iletişim sistemlerini kullanım her geçen gün artmaktadır. Kablosuz sistemler içerisinde önemli bir yeri olan hücresel sistemlerin ve dolayısıyla Baz istasyonların sayısı da yükselmektedir. Artan Baz istasyonlarından kaynaklı elektromanyetik radyasyon (EMR) seviyelerinin ölçülmesi, değerlendirilmesi ve olası tedbirlerin önceden alınması insan sağlığı açısından elzemdir. Bu nedenle, bu çalışmada Ankara ilinin Yenimahalle ilçesinde iki farklı günde ve 100 farklı konumda EMR ölçümleri PMM-8053 EMR ölçüm cihazı kullanılarak yapılmıştır. Ölçümlerde en yüksek elektrik alan şiddeti (Emax) 7.84 V/m, en yüksek ortalama elektrik alan şiddeti (Eavg) ise 2.61 V/m olarak belirlenmiştir. Ölçüm yerlerinin %90’ında Eavg değeri 1 V/m’den daha düşüktür. Her ne kadar ölçülen E değerleri ICNIRP ve BTK tarafından belirlenen limitlerin altında olsa da; maruz kalınan E seviyelerinin halk sağlığını tehdit etmeyecek seviyelerde tutulması açısından düzenli aralıklarla ölçülmesi ve izlenmesi önerilir.

Methods for calculating the electrodynamic characteristics of single and multi-layered planar chiral metamaterials based on fine-wired ideally conducting helices placed in a dielectric container are considered in this paper. The effective dielectric constant of the chiral metamaterial is determined on the basis of the Maxwell - Garnett relations. In this paper the dispersion dependences of the material parameters for the considered metamaterial are obtained. The problems of the plane electromagnetic waves reflection from metastructures based on one and two planar layers of the chiral metamaterial have been solved. The possibility of incident microwave energy discrete multi-frequency concentration at a number of resonant frequencies is proved. The matrix theory for describing a multilayer chiral metamaterial and the obtained relations for the transfer matrices of the chiral layer based on helices are considered. It is proved that a two-layer chiral-dielectric metamaterial based on thin-wire conducting helices near a predetermined frequency allows frequency-selective conversion of a normally incident flux of electromagnetic energy into azimuthal scattering in the plane of the metastructure.

The excitation of upper‐hybrid wake electrostatic wave by interaction of an extraordinary Gaussian wave propagating perpendicular to the external magnetic field in a cold homogeneous plasma is investigated using magnetohydrodynamics theory. The plasma oscillations can be excited due to the charge separation appeared by the ponderomotive force of the electromagnetic wave whose frequency is considered in the lower pass band. By obtaining the equation governing the plasma wake, the dependency of the wake amplitude on the physical parameters is studied. It is observed that larger wake oscillation takes place when the pulse length is approximately close to 3λp/π and the X‐wave frequency is greater than ωp, which means that the phase velocity is less than the speed of light in vacuum (vp < c). [ABSTRACT FROM AUTHOR]

Given the tendency of heavy metals to accumulate in soil and plants, the purpose of this study was to determine the contamination levels of Cd, Ni, Pb, and Zn on peppers (leaves and fruit) grown in contaminated soils in industrial centers. For this purpose, we measured the uptake of the four heavy metals by peppers grown in the heavy metal contaminated soils throughout the four growth stages: two-leaf, growth, flowering, and fruiting, and calculated various vegetation indices to evaluate the heavy metal contamination potentials. Electromagnetic waves were also applied for analyzing the responses of the target plants to various heavy metals. Based on the relevant spectral bands identified by principal component analysis (PCA) and random search methods, a regression method was then employed to determine the most optimal spectral bands for estimating the target hazard quotient (THQ). The THQ was found to be the highest in the plants contaminated by Pb (THQ = 62) and Zn (THQ = 5.07). The results of PCA and random search indicated that the spectra at the bands of b570, b650, and b760 for Pb, b400 and b1030 for Ni, b400 and b880 for Cd, and b560, b910, and b1050 for Zn were the most optimal spectra for assessing THQ. Therefore, in future studies, instead of examining the amount of heavy metals in plants by chemical analysis in the laboratory, the responses of the plants to the electromagnetic waves in the identified bands can be readily investigated in the field based on the established correlations. [ABSTRACT FROM AUTHOR]

This paper uses time delay neural network (TDNN) for predicting electromagnetic (EM) fields scattered from dielectric objects (cylinder, cylinder‐hemisphere, and cylinder‐cone) using: (a) FDTD generated initial field data for similar conducting objects and (b) Statistical information for the nature of fields. Statistical data indicated that the scattered field nature is close to deterministic. The TDNN structure determination uses statistical data for fixing the number of delays and tabular technique to obtain the number of hidden neurons. The TDNN training uses the Levenberg‐Marquardt (LM) algorithm. The model outputs follow standard FDTD results closely. [ABSTRACT FROM AUTHOR]

• In-situ constructing LDHs/SCFs via a facile hydrothermal strategy. • CoNi-/FeNi-/FeCo-LDHs successfully grow in situ on SCFs with three unique structures. • The effective frequency of FC/SCFs reaches 4.48 GHz at a thin thickness of 2.0 mm. Transition metals and carbon materials are known as electromagnetic wave (EMW) nemesis, which can effectively attenuate EMW in the 2–18 GHz frequency band. Herein, three typical transition metal (Fe, Co, Ni) are freely combined into three layered double hydroxides (LDHs) through hydrothermal method and successfully grown in situ on the surface of short carbon fibers (SCFs). The SEM images show that although the three LDHs (CoNi-LDHs, FeNi-LDHs and FeCo-LDHs) are all sheet-like structures, their respective morphologies are completely different and each has its own merits. After calcination treatment at 500 °C, their distinct morphologies are basically retained, while the EMW absorption properties are greatly improved dramatically. Their effective absorption bandwidth (f e) (RL ≤ −10 dB) reached 3.68 GHz, 1.68 GHz and 4.48 GHz at thicknesses of 2.2 mm, 2.2 mm and 2.0 mm, respectively. As an important transition metal-based material, the exploration of LDHs in EMW absorption has just begun. [ABSTRACT FROM AUTHOR]

Summary: Flexibility, protection against harmful electromagnetic (EM) waves, and mimicking movement patterns of human beings are among the most required features of advanced textiles. In this regard, the present study was conducted to investigate the possibility of producing flexible, piezoelectric, and EM‐sensitive multifunctional nanofibers. Porous core‐shell Fe3O4@MnO2 Nanoparticles (NPs) were synthesized and dispersed in poly (vinylidene fluoride) through solution mixing methods in different concentrations. Then, nanofibers were prepared by the electrospinning technique. Extensive characterizations including morphological, structural, piezoelectric response, and EM wave absorbance tests were performed on both synthesized NPs and electrospun mats. The effects of filler content, piezoelectric dimension, and test dynamic condition on the output voltage of the piezoelectric generator were also assessed. FTIR and XRD investigations respectively showed that the β phase content increased up to 10% and 7% in presence of 4% NPs that led to an increase of up to 105% in piezoelectric response (up to 23.5 V). Output voltages increased linearly with slopes of 2.83, 1.92, 0.55, 0.306, and 0.086 by increasing the NP content, frequency, piezoelectric area, force, and thickness, respectively. The results of the study indicated that produced nanofibers can absorb significant EM waves in addition to showing high piezoelectric response. [ABSTRACT FROM AUTHOR]

Helical carbon nanotubes, a type of chiral metamaterial, were employed to investigate their effects as well as the mechanisms to electromagnetic wave shielding and absorption performances of cementitious composites over the frequency range from 2 GHz to 18 GHz. The results demonstrate that the best electromagnetic wave shielding effectiveness (SE) of cementitious composites filled with 7.5 wt.% helical carbon nanotubes is 1.39 times of that of cementitious composites without helical carbon nanotubes. The minimum reflectivity in 20 mm-thickness cementitious composites with 4.5 wt.% helical carbon nanotubes is 2.7 times of that of cementitious composites without helical carbon nanotubes. Cementitious composites with 7.5 wt.% helical carbon nanotubes have smallest matching thickness and the minimum reflectivity of −41.0 dB. By analyzing electromagnetic parameters and conductive mechanisms, it is found that helical carbon nanotubes mainly affect reflection loss ratio in electromagnetic wave shielding and the dielectric loss in electromagnetic wave absorption. Both parameters are attributed to the enhanced conductivity with the increase of helical carbon nanotubes. The percolation zone ranges from 1.5 wt.% to 7.5 wt.% for alternating current resistivity, with conductive path transferring from ion conduction to electron conduction as the content of helical carbon nanotubes increases. Additionally, incorporating helical carbon nanotubes essentially does not cause the decrease in compressive strength of cementitious composites. The results recommend that cementitious composites incorporating carbon nanotube metamaterial with helical chirality present high electromagnetic performances with satisfactory compressive strength. [ABSTRACT FROM AUTHOR]

This study seeks to assess the reaction of the eggplant (Solanum melongena L.) to soil samples contaminated. Following, cultivation, growth, and harvest, the plant samples were prepared and maximum absorption rates of heavy metals were measured in both leaf and fruit. The estimated daily intake (EDI), the target hazard quotient (THQ), and the bio-concentration factor (BCF) were measured at various intervals during the growth period of the plant. Spectral analysis was also performed to assess the reaction of target crops to heavy metals. The results showed that in the second and third stages of plant growth, the THQ values were more than 1 for infected plants with Cd, Pb, and Zn. According to results from the BCF analysis, the absorption rate in Pb, during the growth stages was relatively high, in crops contaminated by Ni was around 1 in the second and third stages, and in plants contaminated by Cd was extremely high. All crops contaminated by heavy metals showed higher reflection rates in the 400–500 and 600–700 nm range. So, using electromagnetic waves during different stages of growth, the reaction of eggplant cultivated in soil samples contaminated by heavy metals is predictable. [ABSTRACT FROM AUTHOR]

The velocity of light is independent of the velocity of its source/observer. But the relative velocity between light and its source/observers is dependent on the velocity of the light source/observer, and this does not conflict with the first assumption. The velocity of light is c everywhere and for everyone, but velocities c + v and c -- v, where v is the velocity of a light source/observer, do not represent the velocity of light, but the relative velocity between light and its source/observer. The velocity of light can, thus, be added to and subtracted from any velocity--giving a measurable relative velocity. A simple and common proof for this is the Doppler effect or the working of the Doppler radar. If there were no relative velocity between the electromagnetic wave and its source/observer, then there would be no Doppler effect nor would the Doppler radar work. In this paper, we will measure experimentally the relative velocity between the electromagnetic wave and the source/observer, using the Doppler effect. [ABSTRACT FROM AUTHOR]

Currently, due to the rapid development of communication technology, electromagnetic interference (EMI) and irradiation have become an emerging environmental pollutant. Herein, hierarchical and porous structured wood is used as the lightweight three‐dimensional organic scaffold for the incorporation of magnetic iron oxide nanoparticles through an in situ mineralization process that endows the woodblock with favorable appearance as well as magnetic and EMI shielding properties. The two‐step process involves the removal of lignin from natural wood via cooking and bleaching followed by inorganic mineralization. The resultant magnetic wood displays an optical brown appearance and possesses a typical magnetic hysteresis behavior with a saturation magnetization of 4.5 emu g−1 for the whole wood. More importantly, the obtained magnetic wood is much lighter than traditional magnetic metal and construable for versatile applications. Notably, the 3 mm thick magnetic wood shows 5–10 dB (or 7–10×) enhanced electromagnetic wave attenuation across the X‐band of 8–12 GHz compared with nonmagnetic wood with the same thickness. The enhanced electromagnetic wave absorption of magnetic wood is mainly due to its enhanced magnetic loss tangent compared with nonmagnetic wood. This work provides an inspiring strategy to develop sustainable, lightweight, and environmentally friendly wood for multifunctional magnetic applications. [ABSTRACT FROM AUTHOR]

The issue of the development and creation of intelligent flow rate sensors of free-flowing and fluid substances carried on pipelines is considered timely during this era of digital conversion of production processes in industry and science. With this objective, this article presents new approaches to improving the measurement precision of microwave flow rate measuring units. Taking into account the characteristics of electromagnetic waves propagating along the pipeline, analysis was conducted of a wave scattered by the inhomogeneities of the medium being monitored. The features of the transformation of a polarized scattered wave, the limiting geometrical sizes of the pipeline, and optimization of the values of the true scattered signal, are revealed. The feasibility of picking up an information signal with orthogonal polarization of the scattered wave, and via a directional coupler, is substantiated. A methodology was developed to estimate measurement precision with an association to the signal-to-noise ratio at input to a processing unit. It has been shown that the results of the studies can be used in the cryogenic engineering industry to measure the volume and mass flow rates of liquid cryoproducts. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A method for separating multisource partial discharges (PDs) in a substation is proposed based on selected bispectra of ultrahigh frequency (UHF) electromagnetic waves. Bispectra are sensitive to Gaussian noises and processes of symmetrical distribution. The phase information contained in bispectra can be useful and important for further signal processing. Bifrequencies where Fisher-like class separability measures between signals' bispectra achieve their maximums are selected as characteristic parameters of the signals. Then, the selected bispectra are utilized for training the radial basis neural network to separate PD UHF signals in a substation. The method is used to analyze simulated UHF signals mixed with Gaussian white noise and frequency-fixed interference, and to separate PD UHF signals that are collected in a 500 kV substation. In order to prove the validity of the proposed separation method, the localization results are compared with the results calculated by time delay sequence, and the proposed separating algorithm is verified in the interference circumstances of a substation. However, the exact location of PD sources cannot be calculated according to the time delay sequence when the PD sources in a substation are close to each other or there are fewer than four antennas for receiving signals. [ABSTRACT FROM AUTHOR]

This article demonstrates a photonic-based wideband true-time delay (TTD) beamforming network employing a raised cosine apodized linearly chirped fiber Bragg grating (FBG) of varying lengths, such as $50\,\,{\times \,\,10^{-3}}$ m, $45\,\,{\times \,\,10^{-3}}$ m, $40\,\,{\times \,\,10^{-3}}$ m, and $35\,\,{\times \,\, 10^{-3}}$ m, and different chirp parameters $25\,\,{\times \,\, 10^{-9}}$ m, $35\,\,{\times \,\, 10^{-9}}$ m, $6\,\,{\times \,\, 10^{-8}}$ m, and $8{\,\,\times \,\,10^{-8}}$ m. The proposed scheme can be used as variable TTD lines having a much lower ripple factor compared with the previously studied apodized linearly CFBG for controlling the radiation angle of phased-array antenna (PAA), i.e., the main lobe radiated by the PAA can be steered squint-free from 0° to ±36.8° suitable for continuous beam forming at microwave frequencies 8–12 GHz extended up to Ku-band. To the best of our knowledge, this is the first experimental demonstration that shows the impact of tuning wavelength on delay change due to raised cosine apodized CFBG in the RF signal fed to the respective element of the antenna array. Four sets of $1\times4$ PAAs have been fabricated with the required electrical parameters, such as reflection coefficient ($S_{11}$), voltage standing wave ratio, gain, far-field radiation pattern, and so on, to show the photonic feed idea. In addition, FBG’s having raised cosine apodization function is fabricated in our collaborative laboratory. [ABSTRACT FROM AUTHOR]

SiC nanowire/siliconboron carbonitride-Silicon nitride (SiC nw /SiBCN-Si 3 N 4) ceramics were prepared via a low-pressure chemical vapor deposition and infiltration (LPCVD/CVI) technique. The as-prepared ceramics were annealed at varying temperatures (1200–1600 °C) in a N 2 atmosphere, and their crystallization mechanism and absorbing properties were subsequently studied. The absorbing properties of the SiC nw /SiBCN-Si 3 N 4 ceramics improved with the annealing temperature up to a certain value and decreased thereafter. Among the samples tested, the SiC nw /SiBCN-Si 3 N 4 ceramics annealed at 1300 °C showed the highest permittivity (real and imaginary parts) and dielectric loss values in the X-band (ca. 5.34, 2.55, and 0.47 respectively), and this could be attributed to the precipitation of carbon and SiC nanocrystals. The sample treated at 1300 °C decreased its minimum reflection coefficient (RC) from −12.0 to −59.68 dB (compared with the as-received SiC nw /SiBCN-Si 3 N 4 ceramics) and the effective RC (below -10 dB) in the whole X-band could be achieved when the thickness was set to 3–3.5 mm. These results revealed that the absorbing performance was significantly improved after the heat treatment at 1300 °C. [ABSTRACT FROM AUTHOR]

In recent years, many wireless communication services have become indispensable for our daily life, such as voice telephoning and the internet surfing. However, these applications also cause lots of concerns related to the health issues. Many people think that the risk of illness will be increased if they are exposed at the electromagnetic field long termly. Therefore, lots of conflicts occurred between the residents and the system operators. Nevertheless, the correlation relation between the electromagnetic field and the specific disease is still unclear. In this paper, we setup a cloud-based measurement system that can measure and record simultaneously the radio intensity of our daily access wireless communication systems, such as the IEEE 802.11 Wi-Fi and 3GPP LTE systems. The system adopts the spectrum analyzer to measure the power of the electromagnetic wave in the considered areas and spectrums. The measured data can be uploaded to the remote database via the internet. Combining the open data sources from the government or the authorities, the quantitative analysis between the radio intensity of wireless communications and the related diseases can be further analyzed. [ABSTRACT FROM AUTHOR]

To protect the antennas of radar stations from the external environment, various radomes are used. The main electrical requirements for these products is the requirement of introducing minimal distortion of electromagnetic waves (EMW) while maintaining strength and protective properties. It is important to identify and localize areas that do not meet the requirements for the magnitude of energy losses, to evaluate their sizes and boundaries. A new method for radomedefectoscopy is proposed, it includes a way for measuring losses under weak anechoic conditions, and for estimating the sizes and shapes of sections that do not meet the requirements for the magnitude of losses. [ABSTRACT FROM AUTHOR]

Electromagnetic pollution has become a serious concern with the immense utilization of wireless information technologies and this has aroused huge interest in the area of microwave absorption. To solve this issue, fabrication of advanced, novel and superior microwave absorbing materials (MAM) with high electromagnetic wave absorption, wide absorption bandwidth, lightweight and cost-efficient are highly required. To date, magnetite (Fe 3 O 4) is being thoroughly investigated as MAM, due to its exceptional dual electromagnetic properties (permittivity and permeability), proper saturation magnetization and high Curie temperature. However, large density and impedance mismatch are some of the limiting factors that hinder its microwave absorption performance (MAP). To circumvent these challenges, reduction of size to the nanoscale, fabrication of hierarchical nanostructures and/or conjugation with other lossy materials have been extensively explored as viable solutions to optimize the MAP of Fe 3 O 4. In this review, the progressive research in the fabrication of Fe 3 O 4 based nanocomposites as MAM is discussed. The factors influencing the MAP of these absorptive materials are likewise discussed in detail. Conclusively, some challenges, limitations, and future prospects in the development of Fe 3 O 4 based MAM are put forth. [ABSTRACT FROM AUTHOR]

Slug flow is widely existed in power engineering, petrochemical industry, nuclear engineering and other fields, and the study of two-phase flow gas slug parameters plays a key role in the precise control of industrial processes. According to the electromagnetic wave propagation theory, considering the cross-correlation algorithm and power spectral density (PSD) principle, a new double embedded U-tube electromagnetic wave phase sensor is designed to build a gas slug parameter measurement system for gas-liquid slug flow. A phase difference model is proposed to measure the velocity of the gas slug, and the mean absolute percent error (MAPE) of the model is 5.35%, with the 87% relative error are within ±10% error band. Experiments are conducted at 70 operating points for the gas-liquid slug flow pattern to predict the gas slug frequency. The PSD function is used to solve for the peak gas slug frequency to obtain the gas slug frequency prediction model for the gas-liquid slug flow. Laboratory results indicate that the MAPE of the model is 14.07%, the 85% relative error are within ±20% error band. In this paper, three literature data are selected to compare with the prediction results of this model, and the MAPE of the Strouhal-Froude (St-Fr) predictive model is 35.51%, 4.78%, and 19.16%, respectively, with a total MAPE of 19.87%, and 90.91% of the literature data are within ±30% error band. The results indicate that the St-Fr model based on gas/liquid superficial velocity has wide applicability in predicting gas slug frequency within the selected data range. And further research is needed on the applicability of the Strouhal-Froude model to other pipeline diameters, gas superficial velocities, and liquid superficial velocities. • A new double embedded U-tube electromagnetic wave phase sensor is designed. • The parameters are calculated according to the cross-correlation and power spectral density principle. • Based on the Strouhal-Froude model, a gas slug frequency prediction model is proposed. • The mean absolute percent error of the model is 14.07%. [ABSTRACT FROM AUTHOR]

• A unique pod-like macroporous carbon nanofibers are prepared by Electrospinning-etching strategy. • The pod-like macroporous carbon nanofibers achieve an ultra-wide absorption bandwidth of 7.6 GHz. • It also exhibits self-cleaning property and radar wave attenuation feature. Constructing multiple polarization losses and improving impedance matching in carbon materials is essential for improving electromagnetic wave absorption performance of carbon materials. Meanwhile, surface contamination of electromagnetic wave absorbers has a significant impact on their absorption performance. Herein, a pod-like macroporous carbon nanofibers with self-cleaning function are successfully prepared by Electrospinning-etching strategy. Through the adjustment of SiO 2 and pore structure, conduction loss, dipole polarization loss, interface polarization loss, and impedance matching of carbon nanofibers are optimized simultaneously. The optimized a pod-like macroporous carbon nanofibers has strong absorption and wide effective absorption bandwidth. With a cavity content of 4 %, the minimum reflection loss at 2.29 mm is -49.36 dB, and the effective absorption bandwidth is 7.6 GHz and the matched thickness is 2.16 mm. This result indicates that cavity and pod-like structure can significantly improve dielectric properties and enhance interface polarization loss and conductivity loss. The simulation results verify that the pod structure has a greater impact on surface electric field distribution, which shows that interface polarization is caused by the cavity structure. In addition, the contact angle of absorber is 105 °, which proves its self-cleaning ability. This functional absorbing material has potential to meet future practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• LiDAR provides real-time and accurate measurement of moisture content in biomass. • The relationship between the moisture content of biomass and its echo intensity has been studied. • Explored the influence of three factors on the echo intensity of moist biomass. • The measurement accuracy of LiDAR is evaluated by the loss-on-drying method. Fast real-time moisture content (MC) measurement of biomass feedstock is important for stable and efficient combustion control in biomass furnaces. In this study, a novel MC measurement method using LiDAR images was proposed based on the calibrated relationship between the signal echo intensity and sample (sawdust and straw) moisture. The experimental results showed that when the MC increased from 0% to 50%, the echo intensity decreased from 5% to 11%, and the relationship between the MC and echo intensity was well fitted by a linear or quadratic function. The influences of the measurement distance, composition, and temperature of the biomass on the measurement accuracy were explored. The absolute measurement error was <4%, and the maximum absolute error was 2.88% for pure sawdust. For the mixed sample (75% straw + 25% sawdust), the maximum absolute error was 3.60%. The optimal measurement distance between the sample and LiDAR was 64 cm, and the maximum absolute error was 3.27%. The influence of temperature between 20 °C and 50 °C on the measurement accuracy was negligible and the maximum absolute error was 3.23% at 30 °C. The verification results confirmed that the proposed LiDAR method can accurately perform online MC measurements. [ABSTRACT FROM AUTHOR]

The burgeoning advancement of electronic technology and wireless communications has opened up an unprecedented era of electromagnetic wave applications, but the accompanying issues of electromagnetic pollution are equally deserving of profound attention. In recent years, a variety of novel electromagnetic absorbers have been ingeniously designed and actively emerged, among which carbon-based materials have become one of the most promising alternatives for next-generation electromagnetic functional materials, owing to the low density, tunable electrical properties, high stability, and chemical tolerance. This article comprehensively reviews the current research status and frontier science of carbon-based absorbing materials serving in microwave frequency band, and discusses in detail the microwave absorption mechanisms of various carbon-based systems as well as the critical factors affecting microwave attenuation. Furthermore, strategies to optimize microwave absorption performance of carbon-based materials through component design, structural modification, morphology modulation, and composite approaches will be discussed, with particular emphasis on their intrinsic correlation with magnetic-dielectric loss characteristics. Finally, the urgent requirements for improving carbon-based absorbing materials and insights into future development are provided, covering from material design to performance optimization to device-based applications. This review endeavors to support valuable references for research on carbon-based microwave absorbing materials and to stimulate further innovative thinking. [Display omitted] [ABSTRACT FROM AUTHOR]