A systematic review and network meta-analysis comparing different epidural steroid injection approaches.

BACKGROUND: Low back pain (LBP) and lumbosacral radiculopathy are frequent disorders that cause nerve root injury, resulting in a variety of symptoms ranging from loss of sensation to loss of motor function depending on the degree of nerve compression. OBJECTIVES: The goal of this study was to investigate the effectiveness of various epidural injection procedures in adult LBP patients. STUDY DESIGN: Systematic review and network meta-analysis. SETTING: Egypt. METHODS: PubMed, Scopus, Web of Science, Cochrane Database, and Embase were used to conduct an electronic literature search. We included RCTs, cohorts, case controls, patients 30 years old with a clinical presentation of low back pain, and comprehensive data on the effects of the intervention on patients with lumbosacral radicular pain who got epidural steroid injections via various techniques. Only papers written in English were eligible. RESULTS: Our analysis showed that parasagittal intralaminar (PIL) was the most effective approach in decreasing VAS (0-10) in the short term (< 6 months) (MD = -1.16 [95% CI -2.04, -0.28]). The next significant approach was transforaminal (TF) (MD = -0.37 [95% CI -1.14, -0.32]) in the long term; TF was the most effective approach (MD = -0.56 [95% CI -1, -0.13]). According to VAS (0-100) in the short term (< 6 months), our analysis showed an insignificant difference among the injection approaches and in the long term; TF was the most effective approach (MD = -24.20 [95% CI -43.80, -4.60]) and the next significant approach was PIL (MD = -23.89 [95% CI -45.78, -1.99]). LIMITATIONS: The main limitations are the heterogeneity encountered in some of our analyses in addition to studies assessed as high risk of bias in some domains. CONCLUSION: TF was the most effective steroid injection approach. In decreasing VAS for short-term PIL and TF were the most significant approaches, but TF was the most effective approach in decreasing VAS for the long term. Also, TF was the most effective approach in decreasing ODI for the long term.

Microporous Activated Carbon from Pisum sativum Pods Using Various Activation Methods and Tested for Adsorption of Acid Orange 7 Dye from Water.

This work demonstrates the preparation of high-surface-area activated carbon (AC) from Pisum sativum pods using ZnCl2 and KOH as activating agents. The influence of CO2 and N2 gases during the carbonization process on the porosity of AC were studied. The highest specific surface area of AC was estimated at 1300 to 1500 m2/g, which presented characteristics of microporous materials. SEM micrographs revealed that chemical activation using an impregnation reagent ZnCl2 increases the porosity of the AC, which in turn leads to an increase in the surface area, and the SEM image showed that particle size diameter ranged between 48.88 and 69.95 nm. The performance of prepared AC for adsorption of Acid Orange 7 (AO7) dye was tested. The results showed that the adsorption percentage by AC (2.5 g/L) was equal to 94.76% after just 15 min, and the percentage of removal increased to be ~100% after 60 min. The maximum adsorption capacity was 473.93 mg g-1. A Langmuir model (LM) shows the best-fitted equilibrium isotherm, and the kinetic data fitted better to the pseudo-second-order and Film diffusion models. The removal of AO7 dye using AC from Pisum sativum pods was optimized using a response factor model (RSM), and the results were reported.

Efficiency of Fe3O4 Nanoparticles with Different Pretreatments for Enhancing Biogas Yield of Macroalgae Ulva intestinalis Linnaeus.

In this work, different pretreatment methods for algae proved to be very effective in improving cell wall dissociation for biogas production. In this study, the Ulva intestinalis Linnaeus (U. intestinalis) has been exposed to individual pretreatments of (ultrasonic, ozone, microwave, and green synthesized Fe3O4) and in a combination of the first three mentioned pretreatments methods with magnetite (Fe3O4) NPs, (ultrasonic-Fe3O4, ozone-Fe3O4 and microwave-Fe3O4) in different treatment times. Moreover, the green synthesized Fe3O4 NPs has been confirmed by FTIR, TEM, XRD, SEM, EDEX, PSA and BET. The maximum biogas production of 179 and 206 mL/g VS have been attained when U. intestinalis has been treated with ultrasonic only and when combined microwave with Fe3O4 respectively, where sediment were used as inoculum in all pretreatments. From the obtained results, green Fe3O4 NPs enhanced the microwave (MW) treatment to produce a higher biogas yield (206 mL/g VS) when compared with individual MW (84 mL/g VS). The modified Gompertz model (R2 = 0.996 was appropriate model to match the calculated biogas production and could be used more practically to distinguish the kinetics of the anaerobic digestion (AD) period. The assessment of XRD, SEM and FTIR discovered the influence of different treatment techniques on the cell wall structure of U. intestinalis.

Comparative study between Dexmedetomidine and Ondansteron for prevention of post spinal shivering. A randomized controlled trial.

BACKGROUND: Regional anesthesia could affect the homeostatic system functions resulting frequently in perioperative hypothermia and consequently shivering. The objective of this trial was to evaluate the efficacy of dexmedetomidine and ondansetron to reduce the incidence and severity of shivering after intrathecal blocks. METHODS: This randomized placebo-controlled trial included 120 patients allocated equally in three groups. All patients were anesthetized by standard intrathecal blocks for surgical procedure at lower half of the body and received one of the study drugs intravenously (IV) according to the group assignments. Group S patients (placebo) were administered saline, Group O (ondansetron) were given 8 mg ondansetron, and Group D (dexmedetomidine) were given 1 µg/kg of dexmedetomidine. Shivering incidence and scores, sedation scores, core body temperature, hemodynamic variables, and incidence of complications (nausea, vomiting, hypotension, bradycardia, over-sedation, and desaturation) were recorded. RESULTS: The incidence and 95% confidence interval (95% CI) of shivering in group S 57.5% (42.18-72.82%) was significantly higher than that of both group O 17.5% (5.73-29.27%), P < 0.001 and group D 27.5% (13.66-41.34%), P = 0.012. However, the difference in the incidence of shivering between group O and group D was comparable, P = 0.425. The sedation scores were significantly higher in group D than those of both group S and group O, P < 0.001. Sedation scores between group S and group O were comparable, P = 0.19. Incidences of adverse effects were comparable between the three groups. CONCLUSION: Prophylactic administrations of dexmedetomidine or ondansetron efficiently decrease the incidence and severity of shivering after spinal anesthesia as compared to placebo without significant difference between their efficacies when compared to each other. TRIAL REGISTRATION: Pan African Clinical Trial Registry (PACTR) under trial number (PACTR201710002706318). 18-10-2017. 'retrospectively registered'.

Experimental, predictive and RSM studies of H2 production using Ag-La-CaTiO3 for water-splitting under visible light.

Ag-La-CaTiO3 was used in place of sacrificial agents to assess the influence of operational factors on hydrogen generation in a photocatalytic water splitting system. After being synthesized, the physicochemical features of this substance were accurately described. Several characterization techniques including UV-Vis spectroscopy, FTIR, XRD, XPS, EDX, SEM, TGA, DRS and BET were applied to study the prepared Ag-La-CaTiO3 photocatalyst. Ag-La-CaTiO3 shows a band in the visible wavelength between 400 and 800 nm at < 560 nm compared to the main CaTiO3 band at 350 nm. Ag 4d5s electrons transition to the conduction band (CB), which is responsible for the absorption band at ~ 560 nm (> 2.21 eV). The effects of catalyst concentration, light intensity, and beginning solution pH on the H2 generation rate may all be evaluated simultaneously using experimental design procedures. Up to a maximum threshold, where a drop in the rate of gas evolution occurs, it was confirmed that the increase in catalyst dose positively affects system productivity. The initial solution pH plays a crucial role in H2 production, and pH = 4 and 10 are the optimum pH with a higher yield of H2 production. The highest total H2 production rate, 6246.09 µmol, was obtained using a catalyst concentration of 700 mg and solution pH equal to 10 under 1200 W Vis lamp for 3 h. For prediction and optimization, a D-Optimal design was applied and the optimal results were pH 4, the catalyst dose of 645.578 mg and 1200 W with H2 production of 6031.11 µmol.

Sources of hydrocarbons and their risk assessment in seawater and sediment samples collected from the Nile Delta coast of the Mediterranean Sea.

The aim of this work is to examine the levels, distribution, bases, and hazards of n-alkanes (n-C9 to n-C20) and PAHs in the seawater and sediments around oil production locations in the whole delta region. The variations in the levels of PAHs and n-alkanes in seawater and sediment of the Nile delta coast of the Mediterranean were investigated using GC-MS/MS. The Σn-alkanes residues ranged between 12.05 and 93.51 mg/L (mean: 50.45 ± 17.49 mg/L) and 4.70 to 84.03 µg/g (mean: 31.02 ± 27.995 µg/g) in seawater and sediments, respectively. Total PAHs concentrations ranged between 4.485 and 16.337 µg/L (average: 9.47 ± 3.69 µg/L) and 1.32 to 28.38 ng/g (average 8.61 ± 7.57 ng/g) in seawater and sediment samples, respectively. The CPI (carbon preference index) values fluctuated between 0.62 and 1.72 (seawater) and from 0.234 to 2.175 (sediment), proposing the variation sources of n-alkane in the studied area. PAHs concentrations were lower than the Effective Range Low (ERL) and Effective Range Median (ERM) levels. The Toxic Equivalent Quotient (TEQ) values oscillated between 0.002 and 6.84 ng/L and from 3.72 to 13.48 ng/g for the seawater and sediment samples, respectively. The Ant/(Ant + Phe) ratio in sediment and seawater samples indicated a pyrolytic source while the BaA/(BaA + Chry) ratio indicates petrogenic sources in most of the studied stations.

Orange peel magnetic activated carbon for removal of acid orange 7 dye from water.

Magnetic activated carbon resources with a remarkably high specific surface area have been successfully synthesized using orange peels as the precursor and ZnCl2 as the activating agent. The impregnation ratio was set at 0.5, while the pyrolysis temperature spanned from 700 to 900 °C. This comprehensive study delved into the influence of activation temperatures on the resultant pore morphology and specific surface area. Optimal conditions were discerned, leading to a magnetic activated carbon material exhibiting an impressive specific surface area at 700 °C. The Brunauer-Emmett-Teller surface area reached 155.09 m2/g, accompanied by a total pore volume of 0.1768 cm3/g, and a mean pore diameter of 4.5604 nm. The material displayed noteworthy properties, with saturation magnetization (Ms) reaching 17.28 emu/g, remanence (Mr) at 0.29 emu/g, and coercivity (Hc) of 13.71 G. Additionally, the composite demonstrated super-paramagnetic behaviour at room temperature, facilitating its rapid collection within 5 s through an external magnetic field. Factors such as absorbent dose, initial concentration of the adsorbate, contact time, and pH were systematically examined. The adsorption behaviour for acid orange 7 (AO7) was found to adhere to the Temkin isotherm models (R2 = 0.997). The Langmuir isotherm model suggested a monolayer adsorption, and the calculated maximum monolayer capacity (Qm) was 357.14 mg/g, derived from the linear solvation of the Langmuir model using 0.75 g/L as an adsorbent dose and 150-500 mg/L as AO7 dye concentrations. The pseudo-second order model proved to be the best fit for the experimental data of AO7 dye adsorption, with a high coefficient of determination (R2) ranging from 0.999 to 1.000, outperforming other kinetic models.

Optimization strategy of Co3O4 nanoparticles in biomethane production from seaweeds and its potential role in direct electron transfer and reactive oxygen species formation.

In the present study, three process parameters optimization were assessed as controlling factors for the biogas and biomethane generation from brown algae Cystoceira myrica as the substrate using RSM for the first time. The biomass amount, Co3O4NPs dosage, and digestion time were assessed and optimized by RSM using Box-Behnken design (BBD) to determine their optimum level. BET, FTIR, TGA, XRD, SEM, XPS, and TEM were applied to illustrate the Co3O4NPs. FTIR and XRD analysis established the formation of Co3O4NPs. The kinetic investigation confirmed that the modified model of Gompertz fit the research results satisfactorily, with R2 ranging between 0.989-0.998 and 0.879-0.979 for biogas and biomethane production, respectively. The results recommended that adding Co3O4NPs at doses of 5 mg/L to C. myrica (1.5 g) significantly increases biogas yield (462 mL/g VS) compared to all other treatments. The maximum biomethane generation (96.85 mL/g VS) was obtained with C. myrica at (0 mg/L) of Co3O4NPs. The impacts of Co3O4NPs dosages on biomethane production, direct electron transfer (DIET) and reactive oxygen species (ROS) were also investigated in detail. The techno-economic study results demonstrate the financial benefits of this strategy for the biogas with the greatest net energy content, which was 2.82 kWh with a net profit of 0.60 USD/m3 of the substrate and was produced using Co3O4NPs (5 mg/L).

Mandarin biochar-CO-TETA was utilized for Acid Red 73 dye adsorption from water, and its isotherm and kinetic studies were investigated.

Environmental pollution is a major issue today due to the release of dyestuff waste into the environment through industrial wastewater. There is a need for affordable and effective adsorbents to remove harmful dyes from industrial waste. In this study, Mandarin biochar-CO-TETA (MBCOT) adsorbent was prepared and used to remove Acid Red 73 (AR73) dye from aqueous solutions. The efficiency of dye removal was influenced by various factors such as solution pH, contact time, initial AR73 dye concentration, and MBCOT dosage. All experiments were conducted at 25 ± 2 °C, and the optimal pH was determined to be 1.5. The optimal conditions for dye removal were found to be an AR73 dye concentration of 100 mg/L, an MBCOT dosage of 1.5 g/L, and a contact time of 150 min, resulting in a 98.08% removal rate. Various models such as pseudo-first-order (PFO), pseudo-second-order (PSO), film diffusion (FD), and intraparticle diffusion (IPD) were used to determine the adsorption kinetics of AR73 dye onto MBCOT. The results showed that the PSO model best explains the AR73 dye adsorption. Furthermore, Langmuir and Freundlich's isotherm models were studied to explain the adsorption mechanism using experimental data. The adsorption capacities at equilibrium (qe) in eliminating AR73 dye varied from 92.05 to 32.15, 128.9 to 65.39, 129.25 to 91.69, 123.73 to 111.77, and 130.54 to 125.01 mg/g. The maximum adsorption capacity (Qm) was found to be 140.85 mg/g. In conclusion, this study demonstrates that biochar produced from mandarin peels has the potential to be an effective and promising adsorbent for removing AR73 dye from water.

Isothermal and kinetic screening of methyl red and methyl orange dyes adsorption from water by Delonix regia biochar-sulfur oxide (DRB-SO).

In this study, Delonix regia seed pods (DRSPs) as a locally available material were refluxed in 90% H2SO4 to yield a novel D. regia seed pods biochar-sulfur oxide (DRB-SO). FTIR, BET, BJH, SEM, EDX, XRD, DSC and TGA were applied to investigate the characterizations of the prepared DRB-SO. Various adsorption parameters like pH effect, dye concentration effect, adsorbent dose, reaction time isotherm and kinetic study were carried out to explain the process of adsorption of methyl orange (MO) and methyl red (MR) onto DRB-SO. Langmuir's adsorption model perfectly explained the adsorption process onto the surface of DRB-SO as a monolayer. The maximum adsorption efficiency of DRB-SO was (98%) and (99.6%) for MO and MR respectively which attained after 150 min with an adsorbent dose of 0.75 g/L. The pseudo-second-order kinetic model best explained the process of adsorption of MO and MR dyes by DRB-SO. The highest observed adsorption amount was as high as 144.9 mg/g for MO dye and 285.7 mg/g for MR dye, comparable with other reported materials based on activated carbon materials. All of the outcomes signposted a prodigious perspective of the fabricated biochar composite material in wastewater treatment. Using the regenerating DRB-SO through an acid-base regeneration process, six cycles of adsorption/desorption were examined. Over the course of the cycles, there was a minor decrease in the adsorption and desorption processes. Also, it was revealed what the most plausible mechanism was for DRB-SO to absorb the ions of the MO and MR dyes.

Inter-Semispinalis Plane Block Versus General Anesthesia for Postoperative Analgesia in Posterior Cervical Spine Surgery: A Randomized Controlled Trial.

Background: Postoperative pain management is crucial for improving patient outcomes following posterior cervical spine surgery. Opioids are effective but carry a risk of respiratory depression. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used but may not provide adequate pain relief and have potential complications. The inter-semispinalis plane (ISPB) block is a novel technique for postoperative analgesia in cervical spine surgery. Objectives: This study aims to evaluate and compare the efficacy of the ISPB with general anesthesia in terms of analgesia, postoperative Visual Analog Scale (VAS) pain scores, patient-surgeon satisfaction levels, and the occurrence of postoperative complications. Methods: This double-blind, randomized controlled trial was blinded to both the patient and the assessor. Fifty adult patients (18 - 60 years old) undergoing elective posterior cervical spine surgery were enrolled. The participants were divided into 2 groups: The ISPB group (receiving bilateral ultrasound-guided ISPB at the C5 level) and the control group (receiving general anesthesia only), with each group comprising 25 patients. The study assessed intraoperative fentanyl use, postoperative VAS pain levels, the need for rescue analgesia, and complications. Results: The ISPB group showed significantly lower intraoperative fentanyl consumption (median 100 vs. 100 - 150 µg, P = 0.022) and lower postoperative pain scores at 1, 8, 12, and 48 hours (P = 0.016, 0.009, 0.005, 0.016). Additionally, the ISPB group required less postoperative pethidine (20% vs. 64%, P = 0.002) and had a longer delay before requesting pethidine (hazard ratio 0.215, P = 0.001). Surgeon satisfaction was significantly higher in the ISPB group (P = 0.003). These results suggest that the ISPB can effectively reduce pain and analgesic requirements. Conclusions: The ISPB is an effective analgesic technique for posterior cervical spine surgery, reducing opioid consumption, providing better pain control, and enhancing surgeon satisfaction without increasing complications. This approach has the potential to improve postoperative care and patient outcomes in this surgical population.

Fabrication of carbon black nanoparticles from green algae and sugarcane bagasse.

There are several industrial uses for carbon black (CB), an extremely fine powdered form of elemental carbon that is made up of coalesced particle aggregates and almost spherical colloidal particles. Most carbon black is produced from petroleum-derived feedstock, so there is a need to find an alternative method to produce CB, which relies on renewable resources such as algae and agricultural waste. A process involving hydrolysis, carbonization, and pyrolysis of green algae and sugarcane bagasse was developed, as the optimal hydrolysis conditions (16N sulfuric acid, 70 °C, 1 h, 1:30 g/ml GA or SC to sulfuric acid ratio), a hydrolysis ratio of 62% for SC and 85% for GA were achieved. The acidic solution was carbonized using a water bath, and the solid carbon was then further pyrolyzed at 900 °C. The obtained carbon black has a high carbon content of about 90% which is confirmed by EDX, XRD, and XPS analysis. By comparison carbon black from sugar cane bagasse (CBB) and carbon black from green algae Ulva lactuca (CBG) with commercial carbon black (CCB) it showed the same morphology which was confirmed by SEM analysis. The BET data, showed the high specific surface area of prepared CB, which was 605 (m2/g) for CBB and 424 (m2/g) for CBG compared with commercial carbon black (CBB) was 50 (m2/g), also the mean pore diameter of CBB, CBG and CCB indicated that CBB and CBG were rich in micropores, but CCB was rich in mesoporous according to IUPAC classification. This study might have created a technique that can be used to make carbon black from different kinds of biomass.

Fabrication of dialysis membrane from cotton Giza 86 cellulose di-acetate prepared using Ac2O and NiCl2 as a new catalyst.

This attempt has been made to synthesize the cellulose di-acetate in a solvent-free acetylation system of cotton Giza 86 cellulose with Ac2O (200 and 300 ml) in the presence of NiCl2.6HO (1.0, 1.5 and 2.0 g) as an effectively available and new catalyst by the conventional reflux and microwave irradiation methods. This study also illustrates the preparation of a dialysis membrane made from a cellulose di-acetate-dichloromethane-methanol-polyethylene glycol (MW: 200) casting solution. The microwave irradiation method for the synthesis of cellulose di-acetate showed excellent yields and short reaction time, which is an important feature of this method. The impact of the two methods on the cellulose di-acetate formation and its used in the dialysis membrane formulations was studied. The experimental degree of substitution of the prepared cellulose di-acetate values (DS = 2.00-2.7) showed an agreement with the calculated values by FTIR and 1H-NMR analysis methods. The formation of cellulose di-acetate with percentage yields varied from 62.85 to 89.85%. The applicability of the prepared membrane in dialysis operation was evaluated in terms of urea clearance, rejection of Bovine Serum Albumin (BSA) and flux of pure water. Characterization of cellulose di-acetate was achieved through 1H-NMR, FTIR, TGA, and BET analyses. The CA-PEG blend membrane was examined by contact angle measurement, porosity, and water uptake of the membrane. The cellulose acetate membrane surface morphology was determined using SEM. It is observable that the fabricated CA-PEG blend membrane from synthesized cellulose di-acetate by using Nickel chloride as a catalyst is showing remarkable rejection of BSA and urea clearance up to 100 and 67.2%, respectively. The present work is promising and applicable in dialysis membranes.

Orange peels magnetic activate carbon (MG-OPAC) composite formation for toxic chromium absorption from wastewater.

This work prepared a composite of orange peels magnetic activated carbon (MG-OPAC). The prepared composite was categorized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), Energy-dispersive X-ray spectroscopy (EDX), Scanning Electron Microscopy (SEM) and vibrating-sample magnetometer (VSM) analyses. The MG-OPAC composite showed the surface area (155.09 m2/g), the total volume of pores (0.1768 cm3/g), and the mean diameter of pores (4.5604 nm). The saturation magnetization (Ms = 17.283 emu/g), remanence (Mr = 0.28999 emu/g) and coercivity (Hc = 13.714 G) were reported for the prepared MG-OPAC. Likewise, at room temperature, the MG-OPAC was in a super-paramagnetic state, which could be collected within 5 S (< 5 S) with an outside magnetic field. Influence of time of contact, absorbent dose, starting concentration of Cr6+ ions, and pH were tested to adjust the absorption process. The absorption behavior of MG-OPAC for hexavalent chromium was investigated by Langmuir (LIM), Freundlich (FIM) and Temkin (TIM) isotherm models (IMs). Applicability of LIM specifies that Cr6+ ions absorption procedure may be monolayer absorption. The maximum monolayer capacity (Qm) premeditated by LIM was 277.8 mg/g. Similarly, the absorption process was tested with different kinetic models like intraparticle diffusion (IPDM), pseudo-first-order (PFOM), Elovich (EM), pseudo-second-order (PSOM), and Film diffusion (FDM). The PSOM was best fitted to the experimental results of Cr6+ ions absorption with R2 ranging between 0.992 and 1.

n-Alkanes and PAHs baseline distributions and sources in the sediments of the Nile Delta coast of the southeastern Mediterranean.

The variations in the levels of n-alkanes and Polycyclic Aromatic Hydrocarbons (PAHs) in the sediment of the Nile Delta coast and extended to Bardaweel Lagoon along the Mediterranean were investigated during September 2021. The total n-alkane concentrations in the sediment samples ranged from 18.85 to 164.37 µg/g with an average value of 51.98 ± 17.49 µg/g. Similarly, the ΣPAHs concentrations ranged between 4.55 and 207.48 ng/g with an average of 27.89 ± 49.82 ng/g. The carbon preference index (CPI) values were in the 0.21 to 1.39 range, indicating variations in the sources of n-alkane at the analyzed locations. The mean carbon number (MCN) values ranged from 7.41 to 15.47, with an average of 13.34 ± 1.69. The levels of both low and high molecular weight PAHs were lower than the median and low effective range values (ERM and ERL). The computed total TEQ value varied from 0.102 to 4.129 ng/g in the sediment samples under investigation.

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in water-sediment system of southern Mediterranean: Concentration, source and ecological risk assessment.

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were studied in the Nile Delta area of Egypt's southern Mediterranean for their environmental impacts, probable sources, and ecological risk assessment. Using the Gas Chromatography Triple Quadrupole technique, the residues of 16 OCPs and 18 PCBs were determined. The total OCPs content in the seawater and sediment samples ranged from 0.108 to 10.97 µg/L and 0.301 to 5.268 ng/g, respectively, while the PCBs residues had values between 0.808 and 1069.75 µg/L in seawater and between not detected and 575.50 ng/g in sediment samples. The findings of the risk evaluation showed that, except for endosulfan-I, OCPs caused little harm in seawater. However, PCB180, PCB153, PCB156, PCB126 and PCB138 posed a comparatively significant risk. The concentration of DDTs was higher than the effect range low and threshold effect level but remained below the effect range median and probable effect level, posing a minimal ecological concern.

Improved methylene blue adsorption from an aqueous medium by ozone-triethylenetetramine modification of sawdust-based biochar.

In this study, sawdust biochar-O3-TETA (SDBT), a novel biochar, was prepared via treatment with 80% sulfuric acid, followed by oxidation by ozone and subsequent treatment with boiling Triethylenetetramine (TETA). Characterization studies of the prepared SDBT adsorbent were performed with SEM-EDX, BET, XRD, BJH, FT-IR, DTA and TGA analyses. The adsorption efficiency of MB dye by SDBT biochar from water was investigated. Methylene Blue (MB) dye absorption was most effective when the solution pH was 12. The maximum removal % of MB dye was 99.75% using 20 mg/L as starting MB dye concentration and 2.0 g/L SDBT dose. The Qm of the SDBT was 568.16 mg/g. Actual results were fitted to Temkin (TIM), Freundlich (FIM), and Langmuir (LIM) isotherm models. The experimental results for SDBT fitted well with all three models. Error function equations were used to test the results obtained from these isotherm models, which showed that the experimental results fit better with TIM and FIM. Kinetic data were investigated, and the pseudo-second-order (PSOM) had R2 > 0.99 and was mainly responsible for guiding the absorption rate. The removal mechanism of the MB dye ions in a base medium (pH 12) may be achieved via physical interaction due to electrostatic interaction between the SDBT surface and the positive charge of the MB dye. The results show that SDBT effectively removes the MB dye from the aqueous environment and can be used continually without losing its absorption efficiency.

Isotherm and kinetic investigations of sawdust-based biochar modified by ammonia to remove methylene blue from water.

Chemical industry effluent may pose significant environmental risks to both human health and the economy if it is not properly managed. As a result, scientists and decision-makers are paying increasing attention to developing a sustainable, low-cost wastewater treatment technique. This work aims to investigate the adsorption of Methylene Blue (MB) dye present in water using biochar derived from sawdust modified by boiling in an ammonia solution (SDBA). The properties of SDBA were characterized by BET, SEM, XRD, BJH, FT-IR, DTA, EDX and TGA analyses. The presence of -OH and -NH groups in SDBA was confirmed by FTIR, which proved that the NH4OH treatment of biochar successfully added nitrogen groups on its surface. The influence of pH (2 to 12), MB dye initial concentration (20 to 120 mg/L), adsorbent dosage (0.5 to 4.0 g/L) and contact time (0 to 180 min) on the adsorption process has been investigated. The adsorption of MB dye is more favorable at basic pH, with optimum adsorption at pH 8. Using a starting concentration of 20 mg/L of MB dye and a 4.0 g/L SDBA dose, the maximum percent clearance of MB dye was 99.94%. Experimental results were fitted to the Freundlich (FIM), Tempkin (TIM) and Langmuir (LIM) isotherm models (IMs). The FIM fitted the equilibrium data well, with a 643.74 mg/g Qm. Various error function models were used to test the data obtained from IMs. According to Error Function results, experimental data showed that it fits better for LIM and FIM. Kinetic studies indicated that the MB dye adsorption procedure followed pseudo-second-order (PSOM) kinetics based on film diffusion (FDM), pseudo-first-order (PFOM) and intra-particle diffusion models (IPDM). MB dye sorption on the SDBA involved electrostatic interaction, surface participation, hydrogen bond and π-π interactions. The adsorption mechanism of MB dye by SDBA was proposed as physical adsorption via the electrostatic attraction process. SDBA is an effective adsorbent in removing MB dye from water. Six adsorption-desorption cycles of the MB dye were run through the regeneration of SDBA with only a minimal amount of adsorption capacity loss, demonstrating the reusability of manufactured SDBA.

Chlorinated pesticides and PCB residues in the Egyptian Western Desert oases sediments.

This preliminary investigation aimed to detect concentrations of chlorinated pesticides and PCBs in 40 sediment samples from three desert oases located in Kharga, Dakhla and Farafra in western Egypt. The residues of 18 PCBs and 16 chlorinated pesticides were measured by GC-MS/MS (SRM) method. The results showed that PCBs and pesticides were present in all studied samples. The concentrations of individual PCBs ranged from undetected to 3.99 ng/g dw in all these sediment samples. The total residue of pesticides (ng/g, dry weight) in sediment samples also varied from 5.18 to 25.92, 5.41 to 29.49, and 5.93 to 24.19 ng/g dw for the Kharga, Dakhla and Farafra Oases, respectively. The concentrations of PCBs and chlorinated pesticides detected in these oasis sediments were lower than that reported for other worldwide locations. According to the recorded concentrations in this baseline study of PCBs and total DDTs, the results revealed the minimal risks to organisms and people in the studied area according to the Effects Range-Low (ERL) and Effects Range-Median (ERM) guideline values.

Composite nanofiber formation using a mixture of cellulose acetate and activated carbon for oil spill treatment.

Oil and organic pollutants are significant disasters affecting the aquatic ecosystem and human health. A novel nanofiber composite from cellulose acetate/activated carbon (CA/AC) was successfully fabricated by the electrospinning technique. CA/AC nanofiber composites were prepared from 10% (w/v) polymer solutions dissolving in DMA/acetone ratio 1:3 (v/v) with adding three different percentages of AC (3.7, 5.5, and 6.7%) to the total weight of CA. The prepared CA/AC nanofiber composite morphology reveals randomly oriented bead-free fibers with submicron fiber diameter. CA/AC nanofiber composites were further characterized by TGA, DSC, and surface area analysis. Water uptake was investigated for fabricated fibers at different pH. Oil adsorption was conducted in both static (oil only) and dynamic (oil/water) systems to estimate the adsorption capacity of prepared composites to treat heavy and light machine oils. The results showed increased oil adsorption capacity incorporating activated carbon into CA nanofiber mats. The maximum sorption capacity reached 8.3 and 5.5 g/g for heavy and light machine oils obtained by CA/AC5.5 (AC, 5.5%). A higher oil uptake was reported for the CA/AC composite nanofibers and showed a constant sorption capacity after the second recycles in the reusability test. Of isotherm models, the most applicable model was the Freundlich isotherm model. The result of kinetic models proved the fit of the pseudo-second-order kinetic model to the adsorption system.