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1.
Sci Rep ; 14(1): 5542, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448468

RESUMO

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.


Assuntos
Clorófitas , 60578 , Nanopartículas , Saccharum , Ácidos Sulfúricos , Ulva , Celulose , Fuligem , Carbono
2.
Sci Rep ; 14(1): 5075, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429365

RESUMO

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).


Assuntos
Cobalto , Nanopartículas , Óxidos , Alga Marinha , Espécies Reativas de Oxigênio , Biocombustíveis , Elétrons
3.
Sci Rep ; 14(1): 5082, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429376

RESUMO

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.

4.
Sci Rep ; 14(1): 1019, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200036

RESUMO

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.

5.
Sci Rep ; 14(1): 119, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167469

RESUMO

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.

6.
Pain Pract ; 24(2): 341-363, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37700550

RESUMO

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.


Assuntos
Dor Lombar , Radiculopatia , Adulto , Humanos , Dor Lombar/tratamento farmacológico , Metanálise em Rede , Resultado do Tratamento , Dor nas Costas , Radiculopatia/tratamento farmacológico , Injeções Epidurais/métodos , Esteroides/uso terapêutico
7.
Sci Rep ; 13(1): 18871, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37914771

RESUMO

This work examined the polycyclic aromatic hydrocarbons (PAHs) and n-alkanes quantities, sources, and hazards in sediments collected from the Egyptian Western Desert Oases namely: Dakhla, Kharga and Farafra oases. The n-alkane (C9-C20) residue concentrations have ranged from 0.66 to 2417.91 µg/g recorded for the three Oases. On the other hand, the total n-alkane ranged from 448.54 µg/g to 8442.60 µg/g. Higher carbon preference index (CPI) values (> 1.0) proposed that the natural sources could be the main contributor to n-alkanes in the Oases sediment. GC-MS/MS (selected reaction monitoring (SRM) method) was used for the determination of the ΣPAHs concentrations in the studied sediments. The ΣPAHs concentrations (ng/g, dry weight) in the studied three Oases varied from 10.18 to 790.14, 10.55 to 667.72, and from 38.27 to 362.77 for the Kharga, Dakhla and Farafra Oases, respectively. The higher molecular weight PAHs were the most abundant compounds in the collected samples. Assessing potential ecological and human health issues highlighted serious dangers for living things and people. All the investigated PAHs had cancer risk values between 1.43 × 10-4 and 1.64 × 10-1, this finding suggests that PAHs in the samples under study pose a moderate risk of cancer. The main sources of PAHs in this study are biomass, natural gas, and gasoline/diesel burning emissions.


Assuntos
Neoplasias , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Humanos , Egito , Espectrometria de Massas em Tandem , Hidrocarbonetos , Hidrocarbonetos Policíclicos Aromáticos/análise , Alcanos/análise , Medição de Risco , Sedimentos Geológicos/química , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , China
8.
Pain Physician ; 26(7): E787-E796, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37976482

RESUMO

BACKGROUND: The gold standard postoperative analgesia protocol for arthroscopic rotator cuff repair procedures is the interscalene block (ISB), which prevents the significant consequences of phrenic nerve block associated with hemidiaphragmatic paralysis (HDP). The infraclavicular brachial plexus block (BPB) combined with the suprascapular nerve block (SSNB) had the same analgesic efficacy as the infraclavicular BPB alone, with no effect on respiration. OBJECTIVES: Therefore, the study aimed to assess the HDP and analgesic efficacy of both approaches in controlling pain following arthroscopic rotator cuff repair surgeries. STUDY DESIGN: A prospective, randomized, double-blind, and comparative clinical trial. SETTING: The study comprised 66 patients. They were separated into 2 equal parallel groups 33 patients each: the ISB group and the costoclavicular and suprascapular block (CSB) group. METHODS: The ISB group obtained the ISB followed by the general anesthesia. The CSB group received infraclavicular blockade using the costoclavicular approach and SSNB followed by general anesthesia. RESULTS: Considering morphine utilization during the first day following the operation, the groups demonstrated an insignificant difference. The CSB group showed a decreased rate of diaphragmatic paralysis. LIMITATIONS: There was no control group. And, the blocks might take a long time to be performed up to 30 minutes. Also, there were no validated criteria to define HDP based on M-mode ultrasound measurements. CONCLUSIONS: The employment of the costoclavicular block in combination with the suprascapular block may provide a comparable analgesic potency to the sole use of the standard ISB with no HDP.


Assuntos
Bloqueio do Plexo Braquial , Humanos , Bloqueio do Plexo Braquial/métodos , Manguito Rotador/cirurgia , Estudos Prospectivos , Dor Pós-Operatória/prevenção & controle , Analgésicos , Artroscopia/métodos , Anestésicos Locais/uso terapêutico
9.
Top Curr Chem (Cham) ; 381(6): 31, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37906318

RESUMO

Human existence and societal growth are both dependent on the availability of clean and fresh water. Photocatalysis is a type of artificial photosynthesis that uses environmentally friendly, long-lasting materials to address energy and environmental issues. There is currently a considerable demand for low-cost, high-performance wastewater treatment equipment. By changing the structure, size, and characteristics of nanomaterials, the use of nanotechnology in the field of water filtration has evolved dramatically. Semiconductor-assisted photocatalysis has recently advanced to become among the most promising techniques in the fields of sustainable energy generation and ecological cleanup. It is environmentally beneficial, cost-effective, and strictly linked to the zero waste discharge principle used in industrial effluent treatment. Owing to the reduction or removal of created unwanted byproducts, the green synthesis of photoactive nanomaterial is more beneficial than chemical synthesis approaches. Furthermore, unlike chemical synthesis methods, the green synthesis method does not require the use of expensive, dangerous, or poisonous ingredients, making it a less costly, easy, and environmental method for photocatalyst synthesis. This work focuses on distinct greener synthesis techniques utilized for the production of new photocatalysts, including metals, metal doped-metal oxides, metal oxides, and plasmonic nanostructures, including the application of artificial intelligence and machine learning to the design and selection of an innovative photocatalyst in the context of energy and environmental challenges. A brief overview of the industrial and environmental applications of photocatalysts is also presented. Finally, an overview and recommendations for future research are given to create photocatalytic systems with greatly improved stability and efficiency.


Assuntos
Inteligência Artificial , Nanoestruturas , Humanos , Indústrias , Aprendizado de Máquina , Óxidos
10.
Mar Pollut Bull ; 196: 115692, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37871457

RESUMO

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.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Poluentes Químicos da Água , Bifenilos Policlorados/análise , Água/análise , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Medição de Risco , Monitoramento Ambiental/métodos
11.
Sci Rep ; 13(1): 12724, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37543711

RESUMO

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.

12.
Sci Rep ; 13(1): 12431, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528164

RESUMO

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.

13.
Mar Pollut Bull ; 193: 115236, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37418808

RESUMO

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.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Poluentes Químicos da Água , Humanos , Bifenilos Policlorados/análise , Praguicidas/análise , Hidrocarbonetos Clorados/análise , Egito , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Monitoramento Ambiental
14.
Mar Pollut Bull ; 194(Pt B): 115262, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37467685

RESUMO

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.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Hidrocarbonetos Policíclicos Aromáticos/análise , Alcanos/análise , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Monitoramento Ambiental
15.
Sci Rep ; 13(1): 9919, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37336947

RESUMO

The present study fabricated regenerated cellulose nanofiber incorporated with activated carbon and functionalized rC/AC3.7 with EDTA reagent for methylene blue (MB) dye removal. The rC/AC3.7 was fabricated by electrospinning cellulose acetate (CA) with activated carbon (AC) solution followed by deacetylation. FT-IR spectroscopy was applied to prove the chemical structures. In contrast, BET, SEM, TGA and DSC analyses were applied to study the fiber diameter and structure morphology, the thermal properties and the surface properties of rC/AC3.7-EDTA. The CA was successfully deacetylated to give regenerated cellulose nanofiber/activated carbon, and then ethylenediaminetetraacetic acid dianhydride was used to functionalize the fabricated nanofiber composite. The rC/AC3.7-EDTA, rC/AC5.5-EDTA and rC/AC6.7-EDTA were tested for adsorption of MB dye with maximum removal percentages reaching 97.48, 90.44 and 94.17%, respectively. The best circumstances for batch absorption experiments of MB dye on rC/AC3.7-EDTA were pH 7, an adsorbent dose of 2 g/L, and a starting MB dye concentration of 20 mg/L for 180 min of contact time, with a maximum removal percentage of 99.14%. The best-fit isotherm models are Temkin and Hasely. The outcome of isotherm models illustrates the applicability of the Langmuir isotherm model (LIM). The maximal monolayer capacity Qm determined from the linear LIM is 60.61 for 0.5 g/L of rC/AC3.7-EDTA. However, based on the results from error function studies, the generalized isotherm model has the lowest accuracy. The data obtained by the kinetic models' studies exposed that the absorption system follows the pseudo-second-order kinetic model (PSOM) throughout the absorption period.

16.
Environ Sci Pollut Res Int ; 30(26): 69666-69682, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37140854

RESUMO

Zinc oxide nanoparticles (ZnO-NPs) have in recent times shown effective adsorption capability for the confiscation of colour contaminants from aqueous environments (aquatic ecosystems or water bodies) due to the fact that ZnO contains more functional groups. Direct blue 106 (DB106) dye was selected for this present study as a model composite due to its wide range of uses in textiles (cotton and wools), woods, and paper industries, as well as their therapeutic applications, along with its potential for impairments. This study therefore focuses on the use of DB106 dye as a model composite due to its wide range of uses in textiles (cotton and wools), woods, and paper industries, as well as their therapeutic applications and their potential for impairments. Furthermore, the surface functionalization, shape, and composite pore size were revealed by TEM, FTIR, UV, and BET techniques. The current study uses green synthesis method to prepare ZnO-NPs as an adsorbent for the DB106 dye molecules adsorption under various conditions using the batch adsorption process. The adsorption of DB106 dye to the ZnO-NPs biosorbent was detected to be pH-dependent, with optimal adsorption of DB106 (anionic) dye particles observed at pH 7. DB106 dye adsorption to the synthesized ZnO-NPs adsorbent was distinct by means of the linearized Langmuir (LNR) and pseudo-second-order (SO) models, with an estimated maximum adsorption capacity (Qm) of 370.37 mg/g.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Óxido de Zinco , Óxido de Zinco/química , Adsorção , Ecossistema , Poluentes Químicos da Água/química , Nanopartículas/química , Concentração de Íons de Hidrogênio , Cinética
17.
Sci Rep ; 13(1): 5910, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041227

RESUMO

In this study, cellulose hydrogels were simply fabricated by the chemical dissolution method using LiCl/dimethylacetamide as a new method, and the hydrogel produced was investigated for removing Direct Blue 86 (DB86) dye from the aquatic environment. The produced cellulose hydrogel (CAH) was characterized by FTIR, XRD, SEM, and TGA analyses. The removal efficiency of DB86 dye using CAH was achieved via a batch equilibrium process. The impact of pH, time of contact, CAH dosage, starting concentration of DB86 dye, and absorption temperature were scanned. The optimum pH for absorption of DB86 dye was determined to be 2. The absorption results obtained were scanned by Langmuir (LIM), Temkin (TIM), Freundlich (FIM), and Dubinin-Radushkevich (DRIM) isotherm models (IMs) and chi-square error (X2) function used to identify the best-fit IMs. The CAH had 53.76 mg/g as a maximum absorption capacity (Qm) calculated from the LIM plot. The TIM was the best fitted to the CAH absorption results. Kinetic absorption results were investigated by pseudo-first-order (PFOM), Elovich (EM), pseudo-second-order (PSOM), film diffusion (FDM), and intraparticle diffusion (IPDM) models. A PSOM with a high R2 (> 0.99) accounted for the majority of the control over the absorption rate. The findings indicate that CAH can potentially remove the DB86 dye from wastewater.

18.
Pain Physician ; 26(2): 149-159, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36988361

RESUMO

BACKGROUND: Severe postoperative pain is experienced by most patients who undergo spine surgery. Erector spinae plane block (ESPB) is a successful method for postoperative analgesia and has only minor complications. Intrathecal morphine (ITM) demonstrates high efficacy for analgesia up to 24 hours postsurgery. ESPBs and ITM for postoperative analgesia in lumbar spine surgeries have never been compared in prior studies. OBJECTIVES: This study aimed to compare the efficacy of ESPB and ITM in postoperative analgesia after lumbar spine surgeries. STUDY DESIGN: A double-blind prospective comparative study. SETTING: This study was performed at Al Fayoum University Hospital after being confirmed by the local institutional ethical committee (#80) with approval number M520 and retrospectively registered at clinicaltrials.gov number (NCT05123092). METHODS: A prospective randomized double-blinded interventional trial was conducted with 82 patients, 41 in each group. In the ESPB group, a 0.25% bupivacaine injection was used to conduct a bilateral ultrasound-guided ESPB. In the ITM group, an injection of 0.3 mg morphine intrathecally was done. The Visual Analog Scale (VAS) was recorded as the primary outcome. The time to the first analgesic request, intra- and postoperative opioid consumption, hemodynamics, sedation score, and complications were also recorded as secondary outcomes. RESULTS: Postoperative VAS scores were significantly lower in the intrathecal group throughout the postoperative period at all recorded study time points until 48 hours (P < 0.001). Time to the first rescue analgesia and doses of postoperative analgesic required were significant, with a P value of 0.000. Significant differences were found in postoperative oxygen saturation up to 24 hours (P < 0.001) and the sedation score up to 6 hours (P < 0.01). A higher incidence of complications was recorded in the ITM group (P = 0.000). LIMITATIONS: We did not measure patient preoperative VAS scores to ensure that the 2 groups were matched in pain severity. Also, we did not compare patient satisfaction. Another limitation was the inability to determine the degree of pain relief of ESPB since there was no control group in our study. CONCLUSION: We concluded that ITM 0.3 mg provides more potent analgesia up to 48 hours postoperatively than an ESPB, based upon VAS score, analgesic durations, and postoperative analgesic requirements.


Assuntos
Analgesia , Bloqueio Nervoso , Humanos , Morfina/uso terapêutico , Estudos Prospectivos , Bloqueio Nervoso/métodos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Analgésicos Opioides/uso terapêutico , Analgesia/métodos , Ultrassonografia de Intervenção/métodos
19.
Sci Rep ; 13(1): 4268, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36922559

RESUMO

In this study, Pea Peels-Activated Carbon (PPAC), a novel biochar, was created from leftover pea peels (Pisum sativum) by wet impregnation with ZnCl2 and subsequent heating to 600, 700, and 800 °C in a CO2 atmosphere. Investigated how the newly acquired biochar affected the capacity to extract the AY11 dye from the aqueous solution. Through the use of FTIR, XRD, SEM, BJH, BET, DSC, EDX, and TGA studies, the prepared PPAC was identified. It was found that a pH of 2 is optimum for the AY11 dye elimination. The highest removal percentage of AY11 dye was 99.10% using a beginning AY11 dye concentration of 100 mg/L and a 1.0 g/L dose of PPAC. The highest adsorption capacity (Qm) of the PPAC was 515.46 mg/g. Freundlich (FIM), Halsey (HIM), Langmuir (LIM), Tempkin (TIM), and Gineralize (GIM) isotherm models were useful in examining the adsorption results. A variety of error functions, including the average percent errors (APE), root mean square errors (RMS), Marquardt's percent standard deviation (MPSD), hybrid error function (HYBRID), Chi-square error (X2) and a sum of absolute errors (EABS) equations, were also applied to test the isotherm models data. The PPAC experimental data were best suited by the HIM and FIM isotherm models. Elovich (EM), Pseudo-first-order (PFOM), Intraparticle diffusion (IPDM), Pseudo-second-order (PSOM), and Film diffusion (FDM) models were applied to study the kinetic adsorption results. The PSOM had a strong correlation coefficient (R2 > 0.99), and it was principally responsible for controlling the adsorption rate. Anions are typically absorbed during the adsorption mechanism of AY11 dye by PPAC owing to attractive electrostatic forces created with an increase in positively charged areas at acidic pH levels. The regenerated PPAC was used in six successive adsorption/desorption cycles. This study's outcomes show that PPAC successfully removes the AY11 dye from the aqueous solution; as a result, PPAC can be used repeatedly without experiencing considerable loss in effectiveness.

20.
Sci Rep ; 13(1): 2276, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755140

RESUMO

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.

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