Magnetization Process Research Articles

A Comprehensive Timing Analysis of Individual Pulses in X-Ray Bursts from SGR J0501+4516

The pulses in X-ray-burst (XRB) light curves from soft gamma-ray repeaters (SGRs) are generally thought to arise from magnetic crustal fractures or magnetic reconnection, reflecting the evolution of the energy release process in magnetars. In this study, we conduct a comprehensive timing analysis of 27 XRBs from SGR J0501+4156 detected by the Gamma-ray Burst Monitor on board Fermi. Utilizing a improved pulse-finding algorithm, we identify a total of 95 pulses and fit them using multiple FRED functions to obtain pulse-shape parameters based on the Markov Chain Monte Carlo method. We calculate the minimum variability timescales (MVTs) of the XRBs based on the shortest pulse; the distribution of MVTs follows a log-Gaussian function with a mean of 7.22−2.11+2.93 ms (1σ). The distributions of rise time, decay time, waiting time, width, skewness, and peakedness all follow the log-Gaussian function, and multiple power-law dependencies are observed between them; for example, a power-law positive correlation between decay time and rise time with 4.7σ, and a power-law negative correlation between pulse width and peakedness with 6.8σ. Besides, there is a positive correlation with 3.7σ between the number of pulses and burst duration. Our findings favor a magnetospheric origin, and some similarities with gamma-ray bursts imply that they have similar radiation mechanisms, e.g., magnetic reconnection processes.

Separation and utilization of iron, cerium, and other rare earth elements from rare earth waste by chlorination

Due to the lack of effective screening systems in the rare earth waste recycling industry, the composition of rare earth elements in rare earth waste is complex and difficult to separate. In response to such problems, by studying the reaction behavior between various elements in rare earth waste and cobalt chloride, we propose a process path for the separation and recovery of iron, cerium and other rare earth elements using cobalt chloride roasting. The experiments on simulated wastes show that the leaching rates of the Nd, Sm, Gd, Pr can reach 98.31%, 94.5%, 93.87% and 72.05% under the optimal process conditions, respectively. Ce and iron remain in the leaching residue in the form of CeO2 and CoFe2O4, respectively. And through a simple magnetic separation process, CeO2 and CoFe2O4 can be enriched in non-magnetic leaching residue and magnetic leaching residue, respectively. The cerium content in the leaching residue composed of cobalt ferrite is only 1.95%. Therefore, this method is beneficial to the separation and high-value utilization of iron, cerium, and other rare earth elements in the waste system. The research results can provide theoretical reference for the low-cost and high-value recovery of rare earth secondary resources.

Analysis of the Excess Loss in High-Frequency Magnetization Process Through Machine Learning and Topological Data Analysis

Analysis of the Excess Loss in High-Frequency Magnetization Process Through Machine Learning and Topological Data Analysis

Repetitive Head Impacts and Perivascular Space Volume in Former American Football Players

Exposure to repetitive head impacts (RHI) is associated with increased risk for neurodegeneration. Accumulation of toxic proteins due to impaired brain clearance is suspected to play a role. To investigate whether perivascular space (PVS) volume is associated with lifetime exposure to RHI in individuals at risk for RHI-associated neurodegeneration. This cross-sectional study was part of the Diagnostics, Imaging, and Genetics Network for the Objective Study and Evaluation of Chronic Traumatic Encephalopathy (DIAGNOSE CTE) Research Project, a 7-year multicenter study consisting of 4 US study sites. Data were collected from September 2016 to February 2020 and analyses were performed between May 2021 and October 2023. After controlling for magnetic resonance image (MRI) and processing quality, former American football players and unexposed asymptomatic control participants were included in analyses. Prior exposure to RHI while participating in American football was estimated using the 3 cumulative head impact indices (CHII-G, linear acceleration; CHII-R, rotational acceleration; and CHII, number of head impacts). Individual PVS volume was calculated in the white matter of structural MRI. Cognitive impairment was based on neuropsychological assessment. Linear regression models were used to assess associations of PVS volume with neuropsychological assessments in former American football players. All analyses were adjusted for confounders associated with PVS volume. Analyses included 224 participants (median [IQR] age, 57 [51-65] years), with 170 male former football players (114 former professional athletes, 56 former collegiate athletes) and 54 male unexposed control participants. Former football players had larger PVS volume compared with the unexposed group (mean difference, 0.28 [95% CI, 0.00-0.56]; P = .05). Within the football group, PVS volume was associated with higher CHII-R (β = 2.71 × 10-8 [95% CI, 0.50 × 10-8 to 4.93 × 10-8]; P = .03) and CHII-G (β = 2.24 × 10-6 [95% CI, 0.35 × 10-6 to 4.13 × 10-6]; P = .03). Larger PVS volume was also associated with worse performance on cognitive functioning in former American football players (β = -0.74 [95% CI, -1.35 to -0.13]; P = .04). These findings suggest that impaired perivascular brain clearance, as indicated by larger PVS volume, may contribute to the association observed between RHI exposure and neurodegeneration.

Efficiency of magnetic Penrose process in higher dimensional Myers-Perry black hole spacetimes

Efficiency of magnetic Penrose process in higher dimensional Myers-Perry black hole spacetimes

Quantum design of magnetic structures with enhanced magnetocaloric properties

Abstract The magnetization processes and magnetocaloric effect (MCE) of molecular magnets are studied using the quantum Heisenberg model with the goal of finding magnetic structures with optimal magnetocaloric properties. To fulfill this goal, we examine the influence of various factors such as quantum fluctuations, the magnitude and distribution of spins, the cluster size and its geometry on the conventional (cooling) and inverse (heating) MCE. We find, surprisingly, that the best cooling and heating effects are observed in the Ising limit on the smallest possible molecular clusters represented by dimers and trimers. The increasing Heisenberg interaction suppresses both the cooling as well as heating effects, but while the heating is reduced very strongly, for relatively small values of the anisotropic Heisenberg constant, the cooling effects are reduced only weakly. Since the heating effect is undesired in low-temperature refrigeration, the Heisenberg limit is also interesting from a practical point of view. Moreover, we find that spin distributions also have a significant influence on the magnetocaloric properties of molecular magnets. Specifically, configurations with large spins on the edges of the finite chain significantly enhance the cooling effect.

Magnetic irreversibility and magnetization processes in Ni5Al3/NiO core/shell nanoparticle system

This work brings out many interesting facets of magnetism in the Ni5Al3/NiO core/shell nanoparticle system. Theweakandstrongmagnetic irreversibility lines (TWI(H)andTSI(H)) reproduce the previously reportedH - Tphase diagram at fieldsH⩽30 Oe, but strong departures occur forH > 30 Oe. Comparison with the theoretically predictedH - Tphase diagram allows us to identifyTWIwithTCG+SG, where the paramagnetic (PM)-chiral glass (CG) and PM-spin glass (SG) phase transitions occursimultaneously, andTSIwithTSG, the temperature at which transition to the replica symmetry breakingSGstate takes place. TheTSI(H)transition line abruptly ends at the point (H≃30 Oe,T≃90K). AsHexceeds 30 Oe, a new transition appears which gets completely suppressed at fieldsH>1 kOewhere the magnetic irreversibility ceases to exist. Nointrinsiclong-range ferromagnetic ordering exists but fields as low as 3 kOe suffice to induce long-range ferromagnetic order. At fixed temperatures, the magnetocrystalline anisotropy fluctuations essentially govern the 'approach-to-saturation' in magnetization for fields in the range 3 - 70 kOe. The present nanocrystalline system behaves as an isotropic system with random easy axis in which the magnetization reversal occurs through the coherent rotation of the magnetizations of weakly-interacting single-domain Ni5Al3particles. Saturation magnetization, likeM(T) atH⩾2 kOe, exhibits an anomalous upturn at temperatures below ≈ 30 K. This upturn is associated with the anomalous softening of spin-wave modes which results in the thermal excitation of a large number of non-equilibrium (finite lifetime) magnons. At sub-Kelvin temperatures, these magnons undergo Bose-Einstein condensation.

Contributions of interfacial spin–orbit coupling to magnetic and spintronic properties in AuPt/ferromagnet bilayers

We investigate the relationships between various magnetic and spintronic properties within AuPt/ferromagnet (FM) bilayers (FM = CoFe, CoFeB, Py, and Co). A linear correlation between the volume and surface magnetic anisotropies is identified, potentially influenced by the magnetoelastic effect. The FM thickness dependence of the magnetic damping indicates that spin-memory loss due to the interfacial spin–orbit coupling (ISOC) and spin pumping to the heavy-metal layer contribute little to the damping. Instead, a notable contribution from two magnon scattering to the damping is recognized in AuPt/(Co, CoFe, CoFeB) bilayers, possibly originating from a magnetic inhomogeneity due to the ISOC. In addition, in contrast to the magnetic damping, spin–orbit-torque efficiencies are unlikely related to the ISOC in AuPt/FM systems. This work offers valuable insights into the correlations among magnetic and spintronic parameters arising from the interfaces, ultimately aiding in the advancement of magnetic memory and information processing systems.

Biochar accelerates methane production efficiency from Baijiu wastewater: Some viewpoints considering direct interspecies electron transfer

The low pH of Maotai-flavor Baijiu wastewater (MFBW) adversely affects its anaerobic digestion (AD) performance, resulting in low AD efficiency. Here, coconut shell was used to produce biochar. The characteristics of biochar were regulated through acid, alkali, and magnetic modification, respectively. Biochar and modified biochars were applied to assist the AD of MFBW. The results showed that biochar could significantly increase methane yield by 220.8 %–241.7 % with the corresponding soluble chemical oxygen demand (sCOD) degradation increasing by 52.3 %–57.5 % (p < 0.05). Joint modification could significantly enhance the electron donating capacity from 0.0042 to 0.0095 mmol e−1/g (p < 0.05). The combined modification with magnetic alkali had the best stimulating effect on the AD process, which might be related to the conductive particles (Fe3O4) formed during magnetization processes. The modified biochar featured a high degree of surface roughness, a relatively large aperture, and strong electron donating ability, all of which were beneficial to the colonization and microbial growth. Supplementation with biochar resulted in the enrichment of Proteobacteria, Firmicutes, and Actinobacteria, especially for Syntrophomonas (rising from 0.013 % to 6.74 %–10.93 % of relative abundance). These microorganisms are related to the hydrolysis, acidification, and extracellular electron transfer. The enrichment of electroactive microorganism is a prerequisite for improving the direct interspecies electron transfer pathway. This study provides theoretical support for efficient MFBW treatment.

Simulation of Magnetic Separation of Metal Ions in Aqueous Electrolytes

The magnetic separation of metal ions provides an alternative solution to traditional separation techniques such as pyrometallurgy, hydrometallurgy, biometallurgy or electrodialysis. Compared to traditional techniques that either use large amounts of chemicals (usually inorganic acids combined with reducing agent), produce large amounts of sludge as solid waste, consume a large amount of energy, or are difficult to separate ions of different charges [1], the magnetic separation of the metal ions can separate ions based on their magnetic susceptibility. This method is environmentally friendly [2] and consumes a small amount of energy (particularly when the system is designed using permanent magnets instead of electromagnets). The goal of this presentation is twofold. First, we derive the set of transport equations that need to be used to simulate the magnetic separation of metal ions in aqueous solutions. Then, we use these transport equations to simulate the magnetic separation process in various magnetic systems and predict the efficiency of magnetic separation of different systems.The mathematical model developed here is based on coupling the three-dimensional Navier-Stokes equations for flow transport with the drift (migration)-diffusion equations of ion transport [3] in the presence of magnetic field gradients. Both the drift-diffusion model and the Navier-Stokes equations include the magnetic force term as an additional driving force. By solving the entire system of equations self-consistently we analyze the effect of the diffusivity, concentration gradients, magnetic field gradients and fluid velocity over the capturing properties of the system. A detailed presentation of the mathematical model, underlying assumptions of the model, limiting cases, numerical implementation in three-dimensional structures, and simulations results will be presented at the meeting. In addition, we will present predictions for the magnetic separation of Li, Fe, Ni, Mn, and Co from the solution phase. Fortunately, these ions have significantly different magnetic susceptibility, which vary over more than 3 orders of magnitude, and which allows for the efficient extraction and separation of the elements from the solution and from each other.

Thermally-assisted magnetization of magnetic composites for enhanced micro actuator performance: a low-cost approach using permanent magnets

A micro actuator based on magnetic composite materials can control its deformation and movement through varying magnetic fields, showcasing significant applications in fields such as soft robotics and biomedicine. However, existing magnetic composite materials still require complex magnetization processes involving sophisticated equipment and demanding external magnetic fields. This paper proposed a low-cost, thermally-assisted magnetization process based on permanent magnets. It was observed that the maximum magnetic induction intensity on the surface of magnetic composites is linearly correlated with the heating temperature. Additionally, magnetically treated materials at elevated temperatures can achieve traditional high-field magnetization effects at lower field strengths. Specifically, we synthesized a magnetic composite with 50%wt NdFeB@PDMS and investigated the conditions of the thermally-assisted magnetization process based on permanent magnets, along with mechanical and magnetic performance characterization methods. Experimental results indicate that below 200 °C, the tensile strength and elastic modulus of the base material increase with rising temperatures, demonstrating a trend of high-temperature hardening. However, when the temperature exceeds 200 °C, the elevated temperature leads to the decomposition of the base material, resulting in a rapid decrease in the tensile strength and elastic modulus of the magnetic composite. Furthermore, high temperatures can disrupt the magnetic domains of the magnetic material, reducing its coercive force and making it more susceptible to external magnetic fields and heat, thereby compromising the stability of the magnetic material. These findings provide new insights into the development of more stable and controllable magnetic composite materials.

Core Loss Measurements of Ni-Zn Ferrites by Resonant Method and Loss Separation based on Magnetization Process

Core Loss Measurements of Ni-Zn Ferrites by Resonant Method and Loss Separation based on Magnetization Process

Simulation of magnetization process and Faraday effect of magnetic bilayer films

Abstract We described ferromagnetic film and bilayer films composed of two ferromagnetic layers coupled through antiferromagnetic interfacial interaction by classical Heisenberg model and simulated their magnetization state, magnetic permeability, and Faraday effect at zero and finite temperature by using the Landau–Lifshitz–Gilbert (LLG) equation. The results indicate that in a microwave field with positive circular polarization, the ferromagnetic film has one resonance peak while the bilayer film has two resonance peaks. However, the resonance peak disappears in ferromagnetic film, and only one resonance peak emerges in bilayer film in the negative circularly polarized microwave field. When the microwave field’s frequency exceeds the film’s resonance frequency, the Faraday rotation angle of the ferromagnetic film is the greatest, and it decreases when the thickness of the two halves of the bilayer is reduced. When the microwave field’s frequency remains constant, the Faraday rotation angle fluctuates with temperature in the same manner as spontaneous magnetization does. When a DC magnetic field is applied in the direction of the anisotropic axis of the film, the Faraday rotation angle varies with the DC magnetic field and shows a similar shape of the hysteresis loop.

Magnetic Properties of Gd-Doped Bi7Fe3Ti3O21 Aurivillius-Type Ceramics.

The magnetic properties of Aurivillius-phase Bi7Fe3Ti3O21 (BFT) and Bi7-xGdxFe3Ti3O21, where x = 0.2, 0.4, and 0.6 (BGFT), were investigated. Ceramic material undoped (BGF) and doped with Gd3+ ions were prepared by conventional solid-state reaction. In order to confirm that the obtained materials belong to Aurivillius structures, XRD tests were performed. The XRD results confirmed that both the undoped and the gadolinium-doped materials belong to the Aurivillius phases. The qualitative chemical composition of the obtained materials was confirmed based on EDS tests. The temperature dependences of magnetization and magnetic susceptibility were examined for the ceramic material both undoped and doped with Gd3+ ions. The measurements were taken in the temperature range from T = 10 K to T = 300 K. Using Curie's law, the value of the Curie constant was determined, and on its basis, the number of iron ions that take part in magnetic processes was calculated. The value of Curie constant C = 0.266 K, while the concentration of iron ions Fe3+, which influence the magnetic properties of the material, is equal 3.7 mol% (for BFT). Hysteresis loop measurements were also performed at temperatures of T = 10 K, T = 77 K, and T = 300 K. The dependence of magnetization on the magnetic field was described by the Brillouin function, and on its basis, the concentration of Fe3+ ions, which are involved in magnetic properties, was also calculated (3.4 mol% for BFT). Tests showed that the material is characterized by magnetic properties at low temperatures. At room temperature (RT), it has paramagnetic properties. It was also found that Gd3+ ions improve the magnetic properties of tested material.

Application of hydrophobic superparamagnetic nanoparticles in the solvent extraction of nickel aiming to accelerate phase disengagement

This study investigated the application of a magnetic organic phase containing hydrophobic superparamagnetic nanoparticles to accelerate phase disengagement in solvent extraction processes. For this purpose, stearate-modified magnetite nanoparticles were prepared, characterized, and dispersed in 20 vol.% D2EHPA extractant diluted in kerosene to obtain the intended organic phase. The magnetic solvent extraction process of nickel was conducted using the as-prepared magnetic organic phase containing varying concentrations of hydrophobic magnetite nanoparticles in a sulfate medium. The results implied significant decrements of up to four times in the aqueous/organic phase disengagement duration in an external magnetic field with 10 g.L−1 nanoparticles determined as the optimum concentration. Such magnetically accelerated separation was revealed to be the result of colliding and coalescing the size-heterogeneous magnetic organic droplets moving unevenly through the continuous aqueous solution in a separating system. It is also worth mentioning that applying magnetic solvent extraction did not affect the equilibrium extraction behavior of nickel by D2EHPA.

Quantifying the mineral magnetic signature of petroleum systems and their source rocks: a study on the Inner Moray Firth, UK North Sea

SUMMARY This study aims to expand on existing connections between magnetic minerals and hydrocarbons within petroleum systems. Previous studies have focussed on single-source petroleum systems whereas this study, for the first time, analyses a multi-source petroleum system to investigate potential correlations between different kerogen type source rocks and magnetic minerals. To do this, the study investigates the magnetic mineral characteristics of the Inner Moray Firth (IMF), UK North Sea, through room-, low- and high-temperature techniques, and correlates this to published basin and petroleum systems modelling results that show a three-source hydrocarbon mix. Magnetic mineral analysis identifies extensive evidence for magnetite, goethite and siderite, alongside more minor lepidocrocite and iron sulphides. Although we find that magnetite is ubiquitous within the IMF, its abundance is relatively low, and, in contrast, the relatively magnetically weak goethite is more likely the most abundant magnetic mineral throughout the IMF. In agreement with previous studies, we find magnetic enhancement at oil-water contacts (OWCs); however, here, we identify two different magnetic enhancement processes at OWCs in wells, which are dependent on the amount of sulphur available in the local environment. Wells with low levels of sulphur have increasing levels of magnetite towards the OWC, with the magnetic enhancement occurring at the top of the water-saturated section. Sulphur-rich environments display an increase in iron sulphides near the OWC at the bottom of the oil-saturated sediments. Additionally, we confirm the presence of siderite as indicator of upward vertical migration. Combining with petroleum system model predictions, we find direct links between iron hydroxide presence and Type I and II–III kerogen source rocks, and iron sulphide presence with Type II kerogen source rocks. This study shows the potential for further utilization of magnetic mineral analysis within hydrocarbon exploration and petroleum system definition.

Concentration of Silver from Recycling of Fine Powder of Wasted Videogame Printed Circuit Boards through Reverse Froth Flotation and Magnetic Separation Processes

Electronic waste stream grows day by day; printed circuit boards are a kind of solid waste that accounts for 6% of electronic waste. When these are discarded, they can cause soil, water, and air contamination; however, if recycled, these can be considered as a secondary source of metals. Physical comminution of printed circuit boards generates particles with sizes smaller than 250 µm, which are typically not included in the recycling process because they are considered as dust and unvaluable; nevertheless, precious and base metals can be found in these particles. The concentration of metals like silver, among others, from these particles can be achieved by reverse froth flotation in a flotation column followed by magnetic separation of the tails products. A mass balance of the flotation column feed, concentrate, and tails indicates that using a pulp modified with 5 ppm methyl isobutyl carbinol plus 5 g/ton oleic acid (both biodegradable reagents), the concentration of the products improved, resulting in recoveries of 86.13 and 13.87% in the concentrate and tails zones, respectively, with a grade of 74.4% in the tails flow. Magnetic separation of the tails product increases slightly the concentration of silver, reaching a silver grade of 74.5%, a recovery amount similar to those obtained employing complex and environmentally unfriendly processes.

Facile preparation of covalent-organic framework composites for magnetic solid-phase extraction of naphthaleneacetic acid in food prior to HPLC-UV analysis

Novel magnetic covalent organic frameworks (COFs) were prepared by one-pot synthetic strategy and employed as an efficient adsorbent for magnetic solid-phase extraction (MSPE) of naphthaleneacetic acid (NAA) in food samples. Depending on the predesigned the hydrogen bonding, π-π and hydrophobic interactions of magnetic COFs, the efficient and selective extraction process for NAA was achieved within 15 min. The magnetic COFs adsorbent combined with HPLC-UV was devoted to develop a novel quantitative method for NAA in complex food. The method afforded good coefficient in range of 0.002–10.0 µg mL-1 and low limit of detection was 0.0006 µg mL-1. And the newly established method afforded less adsorbent consumption, wider linearity and lower LODs than the reported analytical methods. Ultimately, the method was successfully applied to determine NAA in fresh pear, tomato and peach juice. The magnetic COFs based MSPE coupled with HPLC-UV method provided a simple, efficient and dependable alternative to monitor trace NAA in food samples.

MAF process for aluminum 6060: An analytical temperature modelling and chemo-mechanical analysis

The magnetic abrasive finishing process is a sophisticated micro-finishing process that enhances the surface quality of superalloys, ceramics, and composites. Surface temperature plays a pivotal role in facilitating chemo-mechanical reactions between the processed surface and abrasive particles. In triggering the chemo-mechanical response of the micro-finished surface of Aluminum 6060 (Al-6060), an analytical thermal model derived using Jaeger moving heat formulation to find the flash temperature (FT) and flash time duration (FTD) at the micro-finishing interface of the processed workpiece and the abrasive particles of the magnetic abrasive brush. Furthermore, the present work performed an RSM-based Box Behnken design experiment to analyse and explain the crucial role of machining gap, abrasive weight, Voltage, and rotational speed on surface temperature, machining surface, and hardness. ANOVA highlighted key factors in machining responses. Surface roughness and temperature were notably influenced by voltage (58.42 % and 57.62 %, respectively), while surface hardness primarily depended on abrasive weight (60.65 %). Using the developed model, extreme FT of 880 °C and 810 °C were calculated under specific conditions, along with corresponding FTD required for quasi-steady-state conditions. FT and FTD were identified as sufficient for initiating chemo-mechanical action in the MAF micro-finishing process, depending on contact pressure, the number of abrasive particles, and sliding velocity, which in turn are influenced by magnetic intensity, abrasive ratio, and rotational speed. Furthermore, a detailed examination of the finished surface was carried out using the SEM, EDS and XRD of Al-6060 which shows that the SiC does participate on the finishing surface. Chemical substrates such as Kaolinite (Al2O9Si2), Iron silicide (FeSi), and Cristobalite (O2Si) had formed on the finished surface of Al-6060 due to the chemo-mechanical action between the SiC and workpiece material.

Preparation of magnetic coconut clothing biochar for extracting neonicotinoid insecticides from environmental water samples

In this study, the magnetic coconut clothing biochar hybrid materials were successfully prepared by in-situ method. The obtained magnetic biochar was characterized in detail by using series of analytical techniques. The results showed that the magnetic hybrid materials presented alveolate network structures with abundant large pores and good magnetic separation ability with Fe3O4 nanoparticles obviously attached on the surface of biochar. The magnetic biochar hybrid materials were used as adsorbents during magnetic solid-phase extraction process for extracting neonicotinoid insecticides from environmental water samples. The adsorption and desorption parameters (adsorption time, elution condition, sample volume, sample pH) affecting magnetic solid-phase extraction efficiency were carefully investigated. Under the optimum conditions (adsorption for 15 min, 5 % formic acid-acetonitrile as elution condition, 50 mL of sample volume, 15 mg of magnetic biochar, pH at 5.0), the magnetic solid-phase extraction process based on magnetic coconut clothing biochar hybrid materials coupled with high performance liquid chromatography tandem mass spectrometry for enriching and detecting neonicotinoid insecticides in environmental water samples was established. The good linear relationship in the range of 0.5–200 ng mL−1 with correlation coefficients greater than 0.9989 and the lower limits of detection (0.0017–0.0069 ng·mL−1) were obtained. The recovery in the spiked water samples was in the range of 68.6 %-104.0 % with relative standard deviation from 0.4 % to 9.3 %. These results demonstrated that the established method was highly sensitive, convenient and repeatable for directly analyzing trace neonicotinoid insecticides in environmental water samples. More importantly, the novel biochar from coconut clothing was introduced into sample pretreatment to enrich trace organic pollutants.