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1.
ACS Biomater Sci Eng ; 10(5): 3438-3453, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38564666

RESUMO

Despite being a weaker metal, zinc has become an increasingly popular candidate for biodegradable implant applications due to its suitable corrosion rate and biocompatibility. Previous studies have experimented with various alloy elements to improve the overall mechanical performance of pure Zn without compromising the corrosion performance and biocompatibility; however, the thermal stability of biodegradable Zn alloys has not been widely studied. In this study, TiC nanoparticles were introduced for the first time to a Zn-Al-Cu system. After hot rolling, TiC nanoparticles were uniformly distributed in the Zn matrix and effectively enabled phase control during solidification. The Zn-Cu phase, which was elongated and sharp in the reference alloy, became globular in the nanocomposite. The strength of the alloy, after introducing TiC nanoparticles, increased by 31% from 259.7 to 340.3 MPa, while its ductility remained high at 49.2% elongation to failure. Fatigue performance also improved greatly by adding TiC nanoparticles, increasing the fatigue limit by 47.6% from 44.7 to 66 MPa. Furthermore, TiC nanoparticles displayed excellent phase control capability during body-temperature aging. Without TiC restriction, Zn-Cu phases evolved into dendritic morphologies, and the Al-rich eutectic grew thicker at grain boundaries. However, both Zn-Cu and Al-rich eutectic phases remained relatively unchanged in shape and size in the nanocomposite. A combination of exceptional tensile properties, improved fatigue performance, better long-term stability with a suitable corrosion rate, and excellent biocompatibility makes this new Zn-Al-Cu-TiC material a promising candidate for biodegradable stents and other biodegradable applications.


Assuntos
Implantes Absorvíveis , Cobre , Stents , Zinco , Zinco/química , Zinco/farmacologia , Cobre/química , Cobre/farmacologia , Ligas/química , Humanos , Titânio/química , Titânio/farmacologia , Alumínio/química , Alumínio/farmacologia , Teste de Materiais , Corrosão , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Nanopartículas/química , Nanocompostos/química
2.
Plant Physiol Biochem ; 210: 108626, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615443

RESUMO

Stomatal operation is crucial for optimising plant water and gas exchange and represents a major trait conferring abiotic stress tolerance in plants. About 56% of agricultural land around the globe is classified as acidic, and Al toxicity is a major limiting factor affecting plant performance in such soils. While most of the research work in the field discusses the impact of major abiotic stresses such as drought or salinity on stomatal operation, the impact of toxic metals and, specifically aluminium (Al) on stomatal operation receives much less attention. We aim to fill this knowledge gap by summarizing the current knowledge of the adverse effects of acid soils on plant stomatal development and operation. We summarised the knowledge of stomatal responses to both long-term and transient Al exposure, explored molecular mechanisms underlying plant adaptations to Al toxicity, and elucidated regulatory networks that alleviate Al toxicity. It is shown that Al-induced stomatal closure involves regulations of core stomatal signalling components, such as ROS, NO, and CO2 and key elements of ABA signalling. We also discuss possible targets and pathway to modify stomatal operation in plants grown in acid soils thus reducing the impact of Al toxicity on plant growth and yield.


Assuntos
Alumínio , Estômatos de Plantas , Solo , Alumínio/toxicidade , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/fisiologia , Solo/química , Produtos Agrícolas/metabolismo , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Adaptação Fisiológica/efeitos dos fármacos
3.
Water Sci Technol ; 89(7): 1879-1890, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619909

RESUMO

This study investigated the treatment of wastewater from tomato paste (TP) production using electrocoagulation (EC) and electrooxidation (EO). The effectiveness of water recovery from the pretreated water was then investigated using the membrane process. For this purpose, the effects of independent control variables, including electrode type (aluminum, iron, graphite, and stainless steel), current density (25-75 A/m2), and electrolysis time (15-120 min) on chemical oxygen demand (COD) and color removal were investigated. The results showed that 81.0% of COD and 100% of the color removal were achieved by EC at a current density of 75 A/m2, a pH of 6.84 and a reaction time of 120 min aluminum electrodes. In comparison, EO with graphite electrodes achieved 55.6% of COD and 100% of the color removal under similar conditions. The operating cost was calculated to be in the range of $0.56-30.62/m3. Overall, the results indicate that EO with graphite electrodes is a promising pretreatment process for the removal of various organics. In the membrane process, NP030, NP010, and NF90 membranes were used at a volume of 250 mL and 5 bar. A significant COD removal rate of 94% was achieved with the membrane. The combination of EC and the membrane process demonstrated the feasibility of water recovery from TP wastewater.


Assuntos
Grafite , Solanum lycopersicum , Poluentes Químicos da Água , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Alumínio , Eletrocoagulação/métodos , Água , Eletrodos , Resíduos Industriais/análise
4.
Chemosphere ; 357: 141981, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38626813

RESUMO

Metal-Organic Frameworks (MOFs) are extensively used as electrode material in various sensing applications due to their efficacious porous nature and tunable properties. However, pristine MOFs lack conductive attributes that hinder their wide usage in electrochemical applications. Electropolymerization of several aromatic monomers has been a widely used strategy for preparing conducting electrode materials for various sensing applications in the past decades. Herein, we report a similar approach by employing the electropolymerization method to create a functional polymer layer to enhance the sensitivity of an Aluminium Organic Framework (DUT-4) for the selective detection of Chloramphenicol (CAP) antibiotic in aqueous environment. The combined strategy using the conducting polymer layer with the porous Al MOF provides surpassing electrochemical performance for sensing CAP with regard to the very low detection limit (LOD = 39 nM) and exceptionally high sensitivity (11943 µA mM-1 cm-2). In addition, the fabricated sensor exhibited good selectivity, reproducibility and stability. The developed method was successfully evaluated in various real samples including lake water and river water for CAP detection with good recovery percentages even at lower concentrations.


Assuntos
Alumínio , Cloranfenicol , Técnicas Eletroquímicas , Limite de Detecção , Estruturas Metalorgânicas , Polímeros , Poluentes Químicos da Água , Cloranfenicol/análise , Estruturas Metalorgânicas/química , Poluentes Químicos da Água/análise , Alumínio/análise , Alumínio/química , Polímeros/química , Técnicas Eletroquímicas/métodos , Reprodutibilidade dos Testes , Antibacterianos/análise , Eletrodos , Rios/química , Lagos/química , Lagos/análise
5.
Int J Mol Sci ; 25(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38612522

RESUMO

The multidrug and toxic compound extrusion (MATE) proteins are coding by a secondary transporter gene family, and have been identified to participate in the modulation of organic acid exudation for aluminum (Al) resistance. The soybean variety Glycine max "Tamba" (TBS) exhibits high Al tolerance. The expression patterns of MATE genes in response to Al stress in TBS and their specific functions in the context of Al stress remain elusive. In this study, 124 MATE genes were identified from the soybean genome. The RNA-Seq results revealed significant upregulation of GmMATE13 and GmMATE75 in TBS upon exposure to high-dose Al3+ treatment and both genes demonstrated sequence homology to citrate transporters of other plants. Subcellular localization showed that both proteins were located in the cell membrane. Transgenic complementation experiments of Arabidopsis mutants, atmate, with GmMATE13 or GmMATE75 genes enhanced the Al tolerance of the plant due to citrate secretion. Taken together, this study identified GmMATE13 and GmMATE75 as citrate transporter genes in TBS, which could improve citrate secretion and enhance Al tolerance. Our findings provide genetic resources for the development of plant varieties that are resistant to Al toxicity.


Assuntos
Alumínio , Arabidopsis , Alumínio/toxicidade , Glycine max/genética , Arabidopsis/genética , Membrana Celular , Citratos
6.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612669

RESUMO

The multidrug and toxin efflux (MATE) family participates in numerous biological processes and plays important roles in abiotic stress responses. However, information about the MATE family genes in Torreya grandis remains unclear. In this study, our genome-wide investigation identified ninety MATE genes in Torreya grandis, which were divided into five evolutionary clades. TgMATE family members are located on eleven chromosomes, and a total of thirty TgMATEs exist in tandem duplication. The promoter analysis showed that most TgMATEs contain the cis-regulatory elements associated with stress and hormonal responses. In addition, we discovered that most TgMATE genes responded to abiotic stresses (aluminum, drought, high temperatures, and low temperatures). Weighted correlation network analysis showed that 147 candidate transcription factor genes regulated the expression of 14 TgMATE genes, and it was verified through a double-luciferase assay. Overall, our findings offer valuable information for the characterization of the TgMATE gene mechanism in responding to abiotic stress and exhibit promising prospects for the stress tolerance breeding of Torreya grandis.


Assuntos
Taxaceae , Toxinas Biológicas , Melhoramento Vegetal , Alumínio , Bioensaio , Estresse Fisiológico/genética
7.
Nutrients ; 16(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38613056

RESUMO

Aluminum contamination in parenteral nutrition (PN) solutions can lead to neurotoxicity, reduced bone mass, and liver toxicity, especially in pediatric patients. Ingredients commonly used in PN compounding, such as vitamins, trace elements, calcium, and phosphate salts, contain significant amounts of aluminum. This study aimed to compare aluminum concentrations in multichamber-bag (MCB) and compounded PN for adults and pediatrics. A prospective study assessed aluminum concentrations in various types of MCB and compared them with compounded PN formulations with similar compositions. The types of MCB included Lipoflex® (without electrolytes), Omegaflex®, Finomel®, Smofkabiven® (with and without electrolytes), Olimel®, Clinimix®, and Numeta®. Overall, 80 aluminum determinations were included: 36 for MCBs and 44 for compounded PN. MCBs showed significantly lower aluminum concentrations than compounded PN: 11.37 (SD 6.16) vs. 21.45 (8.08) µg/L, respectively. Similar results were observed for adult (n = 40) and pediatric (n = 40) PN formulations (12.97 (7.74) vs. 20.78 (10.28) µg/L, and 9.38 (2.23) vs. 22.01 (5.82) µg/L, respectively). Significant differences were also found between MCBs depending on the manufacturing company. These findings suggest that MCBs PN offer a safer option for reducing aluminum contamination in PN. Harmonizing regulations concerning aluminum concentrations in PN solutions could help mitigate differences between PN formulations.


Assuntos
Alumínio , Nutrição Parenteral , Adulto , Humanos , Criança , Estudos Prospectivos , Soluções de Nutrição Parenteral , Eletrólitos
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124221, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38569390

RESUMO

The toxicological effect between co-existed antibiotics and metal ions was dangerous to the ecological environment and public health. However, the rapid quantification tools with convenience, accuracy and low cost for the detection of multiple targets were still challenging. Herein, a portable tri-color ratiometric fluorescence paper sensor was constructed by coupling of blue carbon dots and fluorescence imprinted polymer for down/up conversion simultaneous detection of tetracycline and sulfamethazine. Interestingly, the cascade detection of aluminum ion was also realized based on the individual detection system of tetracycline without the assistance of complex coupling reagents. The detection limits of smartphone method for the visual detection of tetracycline, sulfamethazine and aluminum ion were calculated as 0.014 µM, 0.004 µM and 0.019 µM, respectively. The portable fluorescence paper sensor was applied for the visual detection of tetracycline, sulfamethazine and aluminum ion in actual samples successfully with satisfactory recoveries. With the advantages of rapidness, low cost, and portability, the developed portable fluorescence paper sensor provided a new strategy for the visual real-time detection of multiple targets.


Assuntos
Antibacterianos , Pontos Quânticos , Alumínio , Sulfametazina , Fluorescência , Tetraciclina , Carbono , Íons , Corantes Fluorescentes , Espectrometria de Fluorescência , Limite de Detecção
9.
Urolithiasis ; 52(1): 67, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630266

RESUMO

Laser lithotripsy is gaining global prominence and is a dynamically progressing field marked by a continual influx of new and comprehensive research each year. Recently, there has been a noticeable shift toward the adoption of various kinds of lasers, such as holmium: yttrium-aluminum-garnet (Ho:YAG) and thulium fiber (TFL) lasers. Consequently, we aim to conduct a bibliometric analysis to analyze key areas of research activity within scientific publications that center on the utilization of laser techniques in urolithiasis. A search of the literature spanning from 1978 to 2022 was carried out on 25 December 2023 using the Scopus database to explore research related to the application of laser techniques for urolithiasis treatment. Visualization analysis was performed using VOSviewer software (version 1.6.20). We examined 962 publications that met the specified criteria, 791 (82.22%) of which were original articles. The analysis of the retrieved publications indicated a consistent increase in research output from 1978 to 2022; a particularly noteworthy surge occurred after 2003. In particular, the U.S. claimed the leading position as the most productive country, contributing 211 articles (21.93%). However, India had the highest research productivity according to the adjustment index of 19.08. In the European region, 324 publications (33.68% of the total) originated from 25 countries. The Journal of Endourology contributed the most between 1978 and 2022 (n = 96, 9.98%). The most cited paper examined the effectiveness of holmium: yttrium-aluminum-garnet (Ho:YAG) lasers, while a subsequent study focused on the use of a thulium fiber laser (TFL), an emerging laser technology that has gained increased recognition. Co-occurrence analysis revealed three distinct clusters focusing on the types of laser technology, minimally invasive approaches, and success rate/postoperative complications. This comprehensive investigation delves into the global landscape of laser use for the treatment of urolithiasis. This review supports the emerging clinical concept of using various types of laser technology for urolithiasis treatment. Moreover, the hot issues that researchers should focus on based on the findings of this study are the use of different types of laser lithotripsy in view of the surgical approach, success rate and complications.


Assuntos
Alumínio , Hólmio , Túlio , Ítrio , Humanos , Bibliometria , Complicações Pós-Operatórias
10.
Sci Rep ; 14(1): 8836, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632355

RESUMO

Imidacloprid is still a widely used neonicotinoid insecticide that is banned in many countries because of the associated environmental risks. Due to the inefficiency of conventional wastewater treatments for pesticide removal, new treatment methods are being investigated. Electrochemical methods, including electrocoagulation (EC), seem to be promising alternatives considering their effectiveness in removing various pollutants from wastewater. The aim of this study was to investigate the effects of electrode material, current density, ultrasound, and operation time on the efficiency of imidacloprid removal from a model solution by EC. The combination of aluminum electrodes and 20 A of applied current for 20 min resulted in total imidacloprid degradation. A simplified energy balance was introduced as a form of process evaluation. Combining ultrasound with EC resulted in 7% to 12% greater efficacy than using only EC.


Assuntos
Nitrocompostos , Praguicidas , Poluentes Químicos da Água , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Neonicotinoides , Eletrocoagulação , Eletrodos , Alumínio
11.
Clin Oral Investig ; 28(5): 250, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613726

RESUMO

OBJECTIVES: Occlusal sensitivity (OS)-the ability to detect fine objects between opposing teeth-mainly relies on the activity of mechanoreceptors located in the periodontal ligament. We tested whether somatosensory amplification (SSA)-the tendency to perceive normal somatic sensations as being intense, noxious, and disturbing, which plays a critical role in hypervigilance-affects OS. MATERIALS AND METHODS: We measured OS in 66 adults divided into three groups based on their SSA scores (LowSSA, Intermediate - IntSSA, HighSSA) by asking them to bite on aluminum foils (8 to 72 µm thick) and a sham foil, and report whether they felt each foil. We performed 20 trials for each thickness and sham condition (each participant was tested 120 times), and compared the frequency of correct answers (%correct) among groups after adjusting for participants' trait anxiety, depression, self-reported oral behaviors, and masseter cross-sectional area. RESULTS: %correct was affected by the interaction Foil Thickness-by-SSA (p = 0.007). When tested with the 8 µm foil, the HighSSA group had a lower %correct than the IntSSA (contrast estimate [95% CI]: -14.2 [-25.8 - -2.6]; p = 0.012) and the LowSSA groups (-19.1 [-31.5 - -6.6]; p = 0.001). Similarly, with the 24 µm foil, the HighSSA group had a lower %correct compared to the IntSSA (-12.4 [-24.8-0.1]; p = 0.048) and the LowSSA groups (-10.8 [-22.5-0.8]; p = 0.073). CONCLUSION: Individuals with high SSA present with an aberrant occlusal sensitivity. CLINICAL RELEVANCE: Our findings provide novel insights into the relationship between occlusal perception and psychological factors, which may influence an individual's ability to adapt to dental work.


Assuntos
Alumínio , Ansiedade , Adulto , Humanos , Estudos de Casos e Controles , Músculo Masseter , Ligamento Periodontal
12.
Lasers Med Sci ; 39(1): 97, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558189

RESUMO

To study the effect range of the Nd:YAG laser through various levels of cloudy medium for targets with varying grayscale values in vitro. The coated paper cards with grayscale values of 0, 50, 100, and 150 were used as the laser's targets, which were struck straightly with varying energies using three burst modes (single pulse, double pulse, and triple pulse). Six filters (transmittances of 40, 50, 60, 70, 80, and 90) were applied to simulate various levels of cloudy refractive medium. Image J software was used to measure the diameters and regions of the laser spots. The ranges of the Nd:YAG laser spots increased with energy in the same burst mode (P < 0.05). Under the same amount of energy, the ranges of the Nd:YAG laser spot increased with the grayscale value of the targets (P < 0.05). The greater the transmittance of the filters employed, the larger the range of the Nd: YAG laser spots produced. Assuming that the total pulse energy is identical, the effect ranges of multi-pulse burst modes were significantly larger than those of single-pulse burst mode (P < 0.05). The effect range of a Nd:YAG laser grows with increasing energy and the target's grayscale value. A cloudy refractive medium has a negative impact on the effect range of the Nd: YAG laser. The single pulse mode has the narrowest and safest efficiency range.


Assuntos
Alumínio , Lasers de Estado Sólido , Lasers de Estado Sólido/uso terapêutico , Conservação de Recursos Energéticos , Ítrio
13.
Physiol Plant ; 176(3): e14298, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38685770

RESUMO

Aluminium (Al) toxicity causes major plant distress, affecting root growth, nutrient uptake and, ultimately, agricultural productivity. Lentil, which is a cheap source of vegetarian protein, is recognized to be sensitive to Al toxicity. Therefore, it is important to dissect the physiological and molecular mechanisms of Al tolerance in lentil. To understand the physiological system and proteome composition underlying Al tolerance, two genotypes [L-4602 (Al-tolerant) and BM-4 (Al-sensitive)] were studied at the seedling stage. L-4602 maintained a significantly higher root tolerance index and malate secretion with reduced Al accumulation than BM-4. Also, label-free proteomic analysis using ultra-performance liquid chromatography-tandem mass spectrometer exhibited significant regulation of Al-responsive proteins associated with antioxidants, signal transduction, calcium homeostasis, and regulation of glycolysis in L-4602 as compared to BM-4. Functional annotation suggested that transporter proteins (transmembrane protein, adenosine triphosphate-binding cassette transport-related protein and multi drug resistance protein), antioxidants associated proteins (nicotinamide adenine dinucleotide dependent oxidoreductase, oxidoreductase molybdopterin binding protein & peroxidases), kinases (calmodulin-domain kinase & protein kinase), and carbohydrate metabolism associated proteins (dihydrolipoamide acetyltransferase) were found to be abundant in tolerant genotype providing protection against Al toxicity. Overall, the root proteome uncovered in this study at seedling stage, along with the physiological parameters measured, allow a greater understanding of Al tolerance mechanism in lentil, thereby assisting in future crop improvement programmes.


Assuntos
Alumínio , Lens (Planta) , Proteínas de Plantas , Raízes de Plantas , Proteômica , Lens (Planta)/efeitos dos fármacos , Lens (Planta)/fisiologia , Lens (Planta)/genética , Lens (Planta)/metabolismo , Alumínio/toxicidade , Proteômica/métodos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Genótipo , Plântula/efeitos dos fármacos , Plântula/fisiologia , Plântula/genética , Plântula/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteoma/metabolismo , Antioxidantes/metabolismo
14.
BMC Oral Health ; 24(1): 444, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609958

RESUMO

BACKGROUND: This study evaluated the shear bond strength (SBS) of two different polyetheretherketone (PEEK) and CAD-CAM materials after aging. METHODS: A total of 42 frameworks were designed and milled from 2 different PEEK discs (Copra Peek, P and BioHPP, B). P and B frameworks were divided into 3 subgroups (n = 7). 14 slices were prepared each from feldspathic ceramic (Vitablocs Mark II, VM), hybrid nanoceramic (Cerasmart, CS), and polymer-infiltrated ceramic (Vita Enamic, VE) blocks. After surface preparations, the slices were cemented to P and B surfaces. The samples were subjected to thermal aging (5000 cycles). SBS of all the samples was measured. Fractured surfaces were examined by SEM/EDX analysis. The Shapiro-Wilk, Two-way Robust ANOVA and Bonferroni correction tests were used to analyze the data (a = .05). RESULTS: Frameworks, ceramics, and frameworks x ceramics had significant differences (p < 0.05). The highest SBS value was seen in B-VM (p < 0.05). VM offered the highest SBS with both P and B. The differences between P-VM, P-CS, P-VE and B-CS and B-VE were insignificant (p > 0.05). According to EDX analysis, ytterbium and fluorine was seen in B content, unlike P. While VM and CS contained fluorine, barium, and aluminum; sodium and aluminum were observed in the VE structure. CONCLUSION: Bonding of P and B with VM offers higher SBS. VM, CS and VE did not make any difference in SBS for P, however VM showed a significant difference for B.


Assuntos
Alumínio , Benzofenonas , Flúor , Polímeros , Humanos , Polietilenoglicóis , Desenho Assistido por Computador , Cetonas
15.
Zhonghua Yan Ke Za Zhi ; 60(4): 370-373, 2024 Apr 11.
Artigo em Chinês | MEDLINE | ID: mdl-38583061

RESUMO

A 62-year-old female patient presented with no improvement in vision 10 days after undergoing cataract extraction in the right eye. The unaided visual acuity in the right eye was 0.1, and examination with a slit lamp revealed the presence of the intraocular lens with an increased gap between the intraocular lens and the posterior capsule. Anterior segment optical coherence tomography showed a distance of 3.236 mm between the posterior capsule and the posterior surface of the intraocular lens. Based on the medical history, ocular examination, and auxiliary examinations, a diagnosis of right eye capsular blockage syndrome was made. Nd:YAG laser capsulotomy was performed at the anterior capsule outside the optical zone of the intraocular lens. One week later, the posterior capsule adhered to the posterior surface of the intraocular lens, and there was a significant improvement in vision compared to before the procedure.


Assuntos
Terapia a Laser , Lasers de Estado Sólido , Cápsula do Cristalino , Feminino , Humanos , Pessoa de Meia-Idade , Cápsula do Cristalino/cirurgia , Neodímio , Alumínio , Lasers de Estado Sólido/uso terapêutico , Terapia a Laser/métodos , Ítrio , Complicações Pós-Operatórias
16.
Water Res ; 256: 121539, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583335

RESUMO

Inorganic coagulants such as poly aluminum ferric chloride (Al/Fe) are applied conventionally to sewage sludge dewatering and can be retained in the sludge cake, causing its conductivity to increase and generate secondary pollution. To reduce these disadvantages, there is a need to develop alternative, more sustainable chemicals as substitutes for conventional inorganic coagulants. In the present investigation, the application of a polymeric chitosan quaternary ammonium salt (CQAS) is explored as a complete, or partial, replacement for Al/Fe in the context of sludge dewatering processes. Laboratory experiments using digested sewage sludge showed that CQAS could effectively substitute for over 80 % of the Al/Fe inorganic coagulant in the sludge dewatering process. This substitution resulted in a reduction of sludge cake conductivity by more than 50 %. Simulation of sludge dewatering curves and imaging of the sludge surface indicated that the addition of CQAS led to an increase in nanosized pores, and a decrease in the specific resistance of the sludge filter cake as the dosage of Al/Fe decreased to around 30 %. The variations of fluorescence emission, quantum yield and carboxylic and amino groups, suggested that the chelating of Al/Fe decreased due to the bridging effects of CQAS. The CQAS had different flocculation bridging effects on various EPS fractions, which varied the amount of protein chelated with Al/Fe in each fraction. This study provides new information about the benefits of replacing conventional inorganic coagulants with natural organic polymers for sewage sludge dewatering, in terms of reduced sludge cake conductivity and greater dry solids content.


Assuntos
Quitosana , Compostos Férricos , Esgotos , Esgotos/química , Quitosana/química , Compostos Férricos/química , Compostos de Amônio Quaternário/química , Floculação , Cloretos/química , Eliminação de Resíduos Líquidos/métodos , Alumínio/química
17.
Waste Manag ; 182: 11-20, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626501

RESUMO

Recycling aluminium in a rotary furnace with salt-fluxes allows recovering valuable alloys from hard-to-recycle waste/side-streams such as packaging, dross and incinerator bottom ash. However, this recycling route generates large amounts of salt-slag/salt-cake hazardous wastes which can pose critical environmental risks if landfilled. To tackle this issue, the metallurgical industry has developed processes to valorise the salt-slag residues into recyclable salts and aluminium concentrates, while producing by-products such as ammonium sulphate and non-metallic compounds (NMCs), with applications in the construction or chemical industries. This study aims to assess through LCA the environmental impacts of recycling aluminium in rotary furnaces for both salt-slag management routes: valorisation or landfill. It was found that this recycling process brings forth considerable net environmental profits, which increase for all the considered impact categories if the salt-slag is valorised. The main benefits arise from the production of secondary cast aluminium alloys, which is not unexpected due to the high energy intensity of aluminium primary production. However, the LCA results also identify other hotspots which play a significant role, and which should be considered for the optimisation of the process based on its environmental performance, such as the production of by-products, the consumption of energy/fuels and the avoidance of landfilling waste. Additionally, the assessment shows that the indicators for mineral resource scarcity, human carcinogenic toxicity and terrestrial ecotoxicity are particularly benefited by the salt-slag valorisation. Finally, a sensitivity analysis illustrates the criticality of the metal yield assumptions when calculating the global warming potential of aluminium recycling routes.


Assuntos
Alumínio , Incineração , Reciclagem , Incineração/métodos , Reciclagem/métodos , Alumínio/química , Alumínio/análise , Meio Ambiente , Resíduos Industriais/análise , Metalurgia
18.
J Environ Manage ; 358: 120821, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599087

RESUMO

In electroplating sludge, iron (Fe) and aluminum (Al) are common impurities that need to be separated before recycling valuable heavy metals. However, the traditional Fe/Al separation process often leads to significant losses of heavy metals. To address this issue, a new approach was developed to sequentially separate Fe/Al and recycle chromium (Cr) and nickel (Ni) from real electroplating sludge. The sludge contained 4.5% Cr, 1.2% Al, 1.1% Ni, and 14.6% Fe. Initially, the sludge was completely dissolved in a mixture of hydrochloric and nitric acids. The resulting acid solution was then heated to 160 °C for 10 h with the addition of saccharose. This hydrothermal treatment led to the hydrolysis and crystallization of 98.3% of Fe, 31.8% of Cr, 1.1% of Al, and 4.9% of Ni, forming akaganeite-bearing particles. It was observed that the excessive amount of saccharose also improved the removal of Cr, Al, and Ni, but decreased the removal of Fe. After the hydrothermal treatment, the remaining supernatant was adjusted to different pH levels (1.9, 2.9, and 4.5, respectively), and then Al, Cr, and Ni were stepwise extracted using di-(2-ethylhexyl) phosphate acid (P204). The recycling efficiencies achieved were 97.4% for Al, 61.2% for Cr, and 89.3% for Ni. This approach provides a promising method for the stepwise separation of Fe/Al and the recycling of heavy metals from electroplating sludge.


Assuntos
Galvanoplastia , Ferro , Reciclagem , Esgotos , Esgotos/química , Ferro/química , Cromo/química , Metais Pesados/química , Cristalização , Níquel/química , Alumínio/química
19.
Wei Sheng Yan Jiu ; 53(2): 294-299, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38604967

RESUMO

OBJECTIVE: To establish an analytical method for determining the migration of 24 elements in Yixing clay pottery in 4% acetic acid simulated solution by inductively coupled plasma mass spectrometry. METHODS: Four types of Yixing clay pottery, including Yixing clay teapot, Yixing clay kettle, Yixing clay pot, and Yixing clay electric stew pot, were immersed in 4% acetic acid as a food simulant for testing. The migration amount of 24 elements in the migration solution was determined using inductively coupled plasma mass spectrometry. RESULTS: Lithium, magnesium, aluminum, iron, and barium elements with a mass concentration of 1000 µg/L; Lead, cadmium, total arsenic, chromium, nickel, copper, vanadium, manganese, antimony, tin, zinc, cobalt, molybdenum, silver, beryllium, thallium, titanium, and strontium elements within 100 µg/L there was a linear relationship within, the r value was between 0.998 739 and 0.999 989. Total mercury at 5.0 µg/L, there was a linear relationship within, the r value of 0.995 056. The detection limit of the elements measured by this method was between 0.5 and 45.0 µg/L, the recovery rate was 80.6%-108.9%, and the relative standard deviation was 1.0%-4.8%(n=6). A total of 32 samples of four types of Yixing clay pottery sold on the market, including teapots, boiling kettles, casseroles, and electric stewing pots, were tested. It was found that the migration of 16 elements, including beryllium, titanium, chromium, nickel, cobalt, zinc, silver, cadmium, antimony, total mercury, thallium, tin, copper, total arsenic, molybdenum, and lead, were lower than the quantitative limit. The element with the highest migration volume teapot was aluminum, magnesium, and barium; The kettle was aluminum and magnesium; Casserole was aluminum, magnesium, and lithium; The electric stew pot was aluminum. CONCLUSION: This method is easy to operate and has high accuracy, providing an effective and feasible detection method for the determination and evaluation of element migration in Yixing clay pottery.


Assuntos
Arsênio , Mercúrio , Oligoelementos , Acetatos , Alumínio/análise , Antimônio/análise , Arsênio/análise , Bário/análise , Berílio/análise , Cádmio/análise , Cromo , Argila , Cobalto/análise , Cobre , Lítio/análise , Magnésio , Espectrometria de Massas , Mercúrio/análise , Molibdênio/análise , Níquel , Prata/análise , Tálio/análise , Estanho/análise , Titânio/análise , Oligoelementos/análise , Zinco , China
20.
Appl Radiat Isot ; 209: 111323, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38631246

RESUMO

This work investigates the feasibility of yeast-based impedance measurements for retrospective dosimetry applications. The local environment around yeast cells in a previously developed film-badge was modeled using Geant4. A greater dose response was observed when yeast cells were surrounded by an aluminum-polymer structure, which acted as a conversion layer. Bench-top experiments were conducted using a jar-based dosimeter design that directly combined a finely-ground aluminum conversion medium with yeast powder. It was shown when irradiated in the presence of aluminum grains, yeast cells yielded a higher impedance signal, thereby indicating greater radiation-induced damage. Finally, in separate irradiation experiments, lead and aluminum sheets were placed behind yeast samples and the dosimeters were irradiated to 1 Gy. A 2-fold increase in the impedance signal was shown when samples were positioned in close contact with the lead sheet compared to the aluminum sheet. In all experiments, it was shown that the local environment significantly influences radiative energy deposition in yeast cells.


Assuntos
Impedância Elétrica , Saccharomyces cerevisiae , Saccharomyces cerevisiae/efeitos da radiação , Alumínio/química , Radiometria/métodos , Radiometria/instrumentação , Doses de Radiação , Dosímetros de Radiação
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