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1.
Rejuvenation Res ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38666697

RESUMEN

Elevated substance P can be utilized to predict early mortality during the first week of cerebral infarction. Whether aprepitant, a substance P receptor blocker could be utilized to alleviate poststroke pneumonia which is investigated in this study. Intraluminal monofilament model of middle cerebral artery occlusion (MCAO) was constructed in C57BL/6J male mice, and the relative expression of substance P was detected in collected bronchoalveolar lavage fluid (BALF) and lung tissue homogenate at 24 hours, 48 hours, and 72 hours poststroke. On the other hand, different concentrations of aprepitant (0.5, 1, and 2 mg/kg) were atomized and inhaled into MCAO mice. Inflammation cytokines and bacterial load were detected in collected BALF and lung tissue homogenate at 72-hour poststroke, and lung injury was revealed by histological examination. Aprepitant administration decreased total proteins, total cells, neutrophils, and macrophages in BALF. The concentrations of interleukin (IL)-6, IL-1ß, tumor necrosis factor-α, interferon γ, monocyte chemoattractant protein-1, and IL-10 in lung tissue homogenates were also diminished by the administration of aprepitant. In conclusion, aprepitant could attenuate poststroke pneumonia in mice suggesting its potential therapeutic use in the clinic.

2.
ACS Omega ; 9(15): 17577-17591, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38645374

RESUMEN

In this study, graphene oxide (GO) was modified via electrostatic interactions and chemical grafting by silica (SiO2), and two SiO2@GO hybrids (GO-A and GO-B, respectively) with different structures were obtained and carefully characterized. Results confirmed the successful grafting of SiO2 onto the GO surface using both strategies. The distribution of SiO2 particles on the surface of GO-A was denser and more agglomerated, while it was more uniform on the surface of GO-B. Then, epoxy resin (EP)/GO composites were prepared. The curing mechanism of EP/GO composites was studied by differential scanning calorimetry and in situ infrared spectra spectroscopy. Results of tensile tests, hardness tests, dynamic mechanical analysis, and dielectric measurement revealed that EP/GO-B exhibited the highest tensile properties, with a tensile strength of 79 MPa, a 43% increase compared to raw EP. Furthermore, the addition of fillers improved the hardness of EP, and EP/GO-B showed the highest energy storage modulus of 1900 MPa. The inclusion of SiO2@GO hybrid fillers enhanced the dielectric constant, volume resistivity, and breakdown voltage of EP/GO composites. Among these, EP/GO-B displayed the lowest dielectric loss, relatively good insulation, and relatively high volume resistivity and breakdown voltage. A related mechanism was proposed.

3.
Water Res ; 255: 121486, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38564895

RESUMEN

This study used a simple mechanical ball milling strategy to significantly improve the ability of Mn2O3 to activate peracetic acid (PAA) for sustainable and efficient degradation of organic micropollutant (like bisphenol A, BPA). BPA was successfully removed and detoxified via PAA activation by the bm-Mn2O3 within 30 min under neutral environment, with the BPA degradation kinetic rate improved by 3.4 times. Satisfactory BPA removal efficiency can still be achieved over a wide pH range, in actual water and after reuse of bm-Mn2O3 for four cycles. The change in hydrophilicity of Mn2O3 after ball milling evidently elevated the affinity of Mn2O3 for binding to PAA, while the reduction in particle size exposed more active sites contributing partially to catalytic oxidation. Further analysis revealed that BPA oxidation in the ball mill-treated Mn2O3 (bm-Mn2O3)/PAA process mainly depends on the bm-Mn2O3-PAA complex (i.e., Mn(III)-OO(O)CCH3) mediated non-radical pathway rather than R-O• and Mn(IV). Especially, the existence of the Mn(III)-PAA complex was definitely verified by in situ Raman spectroscopy and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Simultaneously, density functional theory calculations determined that PAA adsorbs readily on manganese sites thereby favoring the formation of Mn(III)-OO(O)CCH3 complexes. This study advances an in-depth understanding of the underlying mechanisms involved in the manganese oxide-catalyzed activation of PAA for superior non-radical oxidation of micropollutants.

4.
J Clin Invest ; 134(10)2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502192

RESUMEN

Clarkson disease, or monoclonal gammopathy-associated idiopathic systemic capillary leak syndrome (ISCLS), is a rare, relapsing-remitting disorder featuring the abrupt extravasation of fluids and proteins into peripheral tissues, which in turn leads to hypotensive shock, severe hemoconcentration, and hypoalbuminemia. The specific leakage factor(s) and pathways in ISCLS are unknown, and there is no effective treatment for acute flares. Here, we characterize an autonomous vascular endothelial defect in ISCLS that was recapitulated in patient-derived endothelial cells (ECs) in culture and in a mouse model of disease. ISCLS-derived ECs were functionally hyperresponsive to permeability-inducing factors like VEGF and histamine, in part due to increased endothelial nitric oxide synthase (eNOS) activity. eNOS blockade by administration of N(γ)-nitro-l-arginine methyl ester (l-NAME) ameliorated vascular leakage in an SJL/J mouse model of ISCLS induced by histamine or VEGF challenge. eNOS mislocalization and decreased protein phosphatase 2A (PP2A) expression may contribute to eNOS hyperactivation in ISCLS-derived ECs. Our findings provide mechanistic insights into microvascular barrier dysfunction in ISCLS and highlight a potential therapeutic approach.


Asunto(s)
Síndrome de Fuga Capilar , Modelos Animales de Enfermedad , Óxido Nítrico Sintasa de Tipo III , Factor A de Crecimiento Endotelial Vascular , Animales , Óxido Nítrico Sintasa de Tipo III/metabolismo , Ratones , Síndrome de Fuga Capilar/metabolismo , Síndrome de Fuga Capilar/patología , Humanos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Células Endoteliales/metabolismo , Células Endoteliales/patología , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Endotelio Vascular/fisiopatología , Histamina/metabolismo , Mediadores de Inflamación/metabolismo , NG-Nitroarginina Metil Éster/farmacología , Proteína Fosfatasa 2/metabolismo , Proteína Fosfatasa 2/genética , Masculino
5.
Langmuir ; 40(14): 7710-7722, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38530200

RESUMEN

Improving the limited energy storage capacity of dielectric materials has long been an attractive challenge. In this work, a four-phase hybridized nanocomposite was designed. The linear polymer polyimide (PI) was added to the ferroelectric polymer polyvinylidene fluoride (PVDF) and compounded with a nanoceramic BT@SiO2 with a core-shell structure. The results show that PVDF-PI/BT@SiO2 nanocomposites prepared by a straightforward spin-coating method have a significantly increased discharge energy density. The polymer blends obtain a tightly extended conformation in the amorphous region. Also, this provides an excellent matrix environment for the homogeneous dispersion of fillers. The core-shell structure, as a physical barrier, not only hinders the expansion of the breakdown path but also extends multiple polarization surfaces with gradient variations at the microscopic level. Therefore, the synergistic effect generated by polymer blending and core-shell structure effectively enhances the dielectric and stored energy characteristics of nanocomposites. The dielectric constant is stable at 11.39-18.7, and the dielectric loss is always lower than 0.136. The discharge energy density is 2.5 J/cm3, almost 110% higher than that of the BOPP films (about 1.2 J/cm3). These experimental results suggest that the composite system using core-shell structure and polymer blending is a new way to improve the energy density of dielectric materials.

6.
Obes Facts ; 17(2): 145-157, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38224679

RESUMEN

INTRODUCTION: Longitudinal effect of diet-induced obesity on bone is uncertain. Prior work showed both no effect and a decrement in bone density or quality when obesity begins prior to skeletal maturity. We aimed to quantify long-term effects of obesity on bone and bone marrow adipose tissue (BMAT) in adulthood. METHODS: Skeletally mature, female C57BL/6 mice (n = 70) aged 12 weeks were randomly allocated to low-fat diet (LFD; 10% kcal fat; n = 30) or high-fat diet (HFD; 60% kcal fat; n = 30), with analyses at 12, 15, 18, and 24 weeks (n = 10/group). Tibial microarchitecture was analyzed by µCT, and volumetric BMAT was quantified via 9.4T MRI/advanced image analysis. Histomorphometry of adipocytes and osteoclasts, and qPCR were performed. RESULTS: Body weight and visceral white adipose tissue accumulated in response to HFD started in adulthood. Trabecular bone parameters declined with advancing experimental age. BV/TV declined 22% in LFD (p = 0.0001) and 17% in HFD (p = 0.0022) by 24 weeks. HFD failed to appreciably alter BV/TV and had negligible impact on other microarchitecture parameters. Both dietary intervention and age accounted for variance in BMAT, with regional differences: distal femoral BMAT was more responsive to diet, while proximal femoral BMAT was more attenuated by age. BMAT increased 60% in the distal metaphysis in HFD at 18 and 24 weeks (p = 0.0011). BMAT in the proximal femoral diaphysis, unchanged by diet, decreased 45% due to age (p = 0.0002). Marrow adipocyte size via histomorphometry supported MRI quantification. Osteoclast number did not differ between groups. Tibial qPCR showed attenuation of some adipose, metabolism, and bone genes. A regulator of fatty acid ß-oxidation, cytochrome C (CYCS), was 500% more abundant in HFD bone (p < 0.0001; diet effect). CYCS also increased due to age, but to a lesser extent. HFD mildly increased OCN, TRAP, and SOST. CONCLUSIONS: Long-term high fat feeding after skeletal maturity, despite upregulation of visceral adiposity, body weight, and BMAT, failed to attenuate bone microarchitecture. In adulthood, we found aging to be a more potent regulator of microarchitecture than diet-induced obesity.


Asunto(s)
Adiposidad , Osteoporosis , Ratones , Animales , Femenino , Médula Ósea/metabolismo , Ratones Endogámicos C57BL , Obesidad/etiología , Obesidad/metabolismo , Tejido Adiposo/metabolismo , Peso Corporal , Osteoporosis/metabolismo , Dieta Alta en Grasa/efectos adversos
7.
Int J Biol Macromol ; 268(Pt 1): 129220, 2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-38191116

RESUMEN

In this work, a total of 18 types of choline chloride, betaine, and L-proline-based deep eutectic solvents (DESs) were synthesized to determine the extraction yield of a natural polysaccharide (PSA) from Dysosma versipellis using an ultrasound-assisted extraction method. Results indicate that the choline-oxalic acid-based DES has the best extraction yield for PSA due to the proper physical-chemical properties between PSA and DES. To evaluate the optimal extraction conditions, a response surface methodology was carried out. Under the optimal conditions, the extraction yield of PSA reaches 10.37 % (± 0.03 %), higher than the conventional extraction methods. Findings from FT-IR and NMR suggest that the extracted PSA belongs to a neutral polysaccharide with (1 â†’ 6)-linked α-d-glucopyranose in the main chain. Interestingly, results from various electrochemical measurements show the extracted PSA exhibits excellent corrosion inhibition performance for mild steel (MS) in a 0.5 M HCl solution, with 90.8 % of maximum corrosion inhibition efficiency at 210 mg L-1. SEM and XPS measurements reveal the formation of a protective layer on the MS surface. The adsorption behaviour of extracted PSA well obeys the Langmuir adsorption isotherm containing the chemisorption and physisorption. Additionally, theoretical calculations validate the experimental findings.

8.
BMC Public Health ; 24(1): 337, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297245

RESUMEN

BACKGROUND: Foreign bodies (FBs) are a common emergency in medical institutions, that can occur in any area and among people of any age, which are common public health problems. Understanding the epidemiological characteristics of FBs is crucial for their prevention and control. The purpose of this study was to analyze the epidemiological characteristics of FBs worldwide through the data from the Global Burden of Disease Study 2019 (GBD 2019). METHODS: We obtained data from the GBD 2019, which is an important public database to understand the disease burden of FBs. Joinpoint was used to analyze temporal trends in the incidence and death trends of FBs, which is widely used to study the long-term temporal trend of the burden of diseases. SaTScan was used to detect spatial-temporal clusters of pulmonary aspiration and foreign body in the airway (PAFBA), which is based on a Poisson model, scanning the number of people and diseases in the study area to obtain the spatial-temporal clusters of diseases. RESULTS: Globally, the age-standardized incidence rate (ASIR) and the age-standardized death rate (ASDR) of FBs in 2019 were 869.23/100,000 (679.92/100,000-1120.69/100,000) and 1.55/100,000 (1.41/100,000-1.67/100,000), respectively. The ASIR and ASDR showed downtrends with average annual percent changes (AAPCs) of -0.31% and - 1.47% from 1990 to 2019. Of note, the ASIR showed an uptrend during 2010-2019, especially in high, high-middle, and middle SDI regions. Stratified analysis by age group showed that ASIR increased in each age group in recent years. From 1990 to 2019, the ASDR in the over-70 age group showed an uptrend worldwide, especially in high and high-middle SDI regions. In different types of FBs, the ASDR of PAFBA was the highest. The death burden of PAFBA was mainly clustered in 82 countries during 1993-2007, such as Canada, Cuba, and Mexico. CONCLUSION: The most important goal is to improve public awareness and emergency knowledge of FBs through publicity methods, such as the internet or offline activities, and to improve laws and regulations. Additionally, different age groups need different targeted measures, such as strengthening the care of children, caring for elderly individuals, improving necessary monitoring programs and reporting systems, conducting effective hazard assessments, and publicity and education activities.


Asunto(s)
Cuerpos Extraños , Muerte Perinatal , Niño , Anciano , Femenino , Humanos , Carga Global de Enfermedades , Cuerpos Extraños/epidemiología , Canadá , Costo de Enfermedad , Cuba , Salud Global , Años de Vida Ajustados por Calidad de Vida , Incidencia
9.
ACS Appl Mater Interfaces ; 15(48): 56293-56304, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37976105

RESUMEN

In this work, we synthesized polydopamine nanoparticles (PDNPs-M, M = I, II, III, and IV) with uniform particle sizes but varying l-arginine (Arg) contents (0%, 0.53%, 3.73%, and 6.62%) through a one-pot synthesis approach. Thin-film nanocomposite (TFN) membranes were fabricated via in situ interfacial polymerization (IP). The effects of the PDNPs-M chemical structure on the IP process and the consequent impacts on the structure and properties of the polyamide (PA) selective layer were investigated. The hydrophilicity and dispersibility of PDNPs-M exhibited an upward trend with the Arg content. Furthermore, Arg doping contributes to a denser and smoother PA layer. Among the TFC and TFN membranes, TFN-PDNPs-IV exhibited a water permeability of 3.89 L·m-2·h-1·bar-1 (55.1% higher than that of TFC-0) with a NaCl rejection rate of 98.8%, signifying superior water/salt selectivity. Additionally, TFN-PDNPs-IV exhibited regular pressure stability, commendable acid/alkali stability, and enhanced antifouling properties. These findings highlight the significant impact of nanoparticle hydrophilic functional groups on the structural and functional attributes of TFN membranes, offering a promising approach for developing advanced reverse osmosis membranes.

10.
J Phys Chem Lett ; 14(44): 9986-9995, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37906171

RESUMEN

Side reactions caused by highly active water molecules, including severe corrosion, hydrogen evolution, and dendrite growth, are impediments to the advancement of aqueous zinc ion batteries (ZIBs). Here, inspired by the pivotal role of plant fibers to prevent dehydration in nature, we designed a unique water-retaining plant fiber (WRPF) separator with strong hygroscopic ability to adsorb and trap water molecules. Elaborated theoretical and experimental characterizations prove that high-activity water could be sequestered by a WRPF separator, alleviating water-induced side reactions and accelerating the desolvation of hydrate Zn2+. Prominently, reversible Zn plating and stripping could be realized in Zn//Cu batteries. Even with elevated cathodic mass loading (21.94 mg cm-2), the Zn//VS2 full cell delivers high areal capacity 3.3 mAh cm-2 and well-maintained stability. The present study offers a versatile design strategy for separators using nature-inspired materials, aiming to address the challenging issue of "water" and achieve ultrastable interfacial chemistry of Zn anode.

11.
Water Res ; 246: 120695, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37812978

RESUMEN

Peracetic acid (PAA) is regarded as an environmentally friendly oxidant because of its low formation of toxic byproducts. However, this study revealed the potential risk of generating disinfection byproducts (DBPs) when treating iodine-containing wastewater with PAA. The transformation efficiency of bisphenol A (BPA), a commonly detected phenolic contaminant and a surrogate for phenolic moieties in dissolved organic matter, by PAA increased rapidly in the presence of I-, which was primarily attributed to the formation of active iodine (HOI/I2) in the system. Kinetic model simulations demonstrated that the second-order rate constant between PAA and HOI was 54.0 M-1 s-1 at pH 7.0, which was lower than the generation rate of HOI via the reaction between PAA and I-. Therefore, HOI can combine with BPA to produce iodine disinfection byproducts (I-DBPs). The transformation of BPA and the generation of I-DBPs in the I-/PAA system were highly pH-dependent. Specifically, acidic conditions were more favorable for BPA degradation because of the higher reaction rates of BPA and HOI. More iodinated aromatic products were detected after 5 min of the reaction under acidic and neutral conditions, resulting in higher toxicity towards E. coli. After 12 h of the reaction, more adsorbable organic iodine (AOI) was generated at alkaline conditions because HOI was not able to efficiency transform to IO3-. The presence of H2O2 in the PAA solution played a role in the reaction with HOI, particularly under alkaline conditions. This study significantly advances the understanding of the role of I- in BPA oxidation by PAA and provides a warning to further evaluate the potential environmental risk during the treatment of iodine-bearing wastewater with PAA.


Asunto(s)
Yodo , Contaminantes Químicos del Agua , Purificación del Agua , Ácido Peracético , Desinfección/métodos , Yoduros , Peróxido de Hidrógeno , Aguas Residuales , Escherichia coli , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
12.
Int J Biol Macromol ; 242(Pt 2): 124712, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37148938

RESUMEN

In this work, Glucomannan was modified with dopamine to synthesize a new polysaccharide Schiff base (GAD). After confirmation of GAD by NMR and FT-IR spectroscopic methods, it was introduced as a sustainable corrosion inhibitor with excellent anti-corrosion action for mild steel in 0.5 M hydrochloric acid (HCl) solution. Employing electrochemical test, morphology measurement, and theoretical analysis, the anticorrosion performance of GAD on mild steel in 0.5 M HCl solution is determined. Maximum efficiency of GAD for suppressing the corrosion rate of mild steel at 0.12 g L-1 reaches 99.0 %. After immersion in HCl solution for 24 h, the results from scanning electron microscopy indicate that GAD is firmly attached to the mild steel surface by making a protective layer. According to the X-ray photoelectron spectroscopy (XPS), FeN bonds existed on the steel surface indicate the presence of chemisorption between GAD and Fe to form stable complexes attracted to the active position on the mild steel. The effects of Schiff base groups on the corrosion inhibition efficiencies were also investigated. Moreover, the inhibition mechanism of GAD was further illustrated by the free Gibbs energy, quantum chemical calculation and molecular dynamics simulation.


Asunto(s)
Dopamina , Ácido Clorhídrico , Ácido Clorhídrico/química , Espectroscopía Infrarroja por Transformada de Fourier , Acero/química , Bases de Schiff , Ácidos
13.
Front Psychiatry ; 14: 1100849, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36860503

RESUMEN

Backgrounds: The widespread coronavirus disease 2019 (COVID-19) outbreak impacted the mental health of infected patients admitted to Fangcang shelter hospital a large-scale, temporary structure converted from existing public venues to isolate patients with mild or moderate symptoms of COVID-19 infection. Objective: This study aimed to investigate the risk factors of the infected patients from a new pharmacological perspective based on psychiatric drug consumption rather than questionnaires for the first time. Methods: We summarised the medical information and analysed the prevalence proportion, characteristics, and the related risk factors of omicron variants infected patients in the Fangcang Shelter Hospital of the National Exhibition and Convention Center (Shanghai) from 9 April 2022 to 31 May 2022. Results: In this study, 6,218 individuals at 3.57% of all admitted patients in the Fangcang shelter were collected suffering from mental health problems in severe conditions including schizophrenia, depression, insomnia, and anxiety who needed psychiatric drug intervention. In the group, 97.44% experienced their first prescription of psychiatric drugs and had no diagnosed historical psychiatric diseases. Further analysis indicated that female sex, no vaccination, older age, longer hospitalization time, and more comorbidities were independent risk factors for the drug-intervened patients. Conclusion: This is the first study to analyse the mental health problems of omicron variants infected patients hospitalised in Fangcang shelter hospitals. The research demonstrated the necessity of potential mental and psychological service development in Fangcang shelters during the COVID-19 pandemic and other public emergency responses.

14.
J Hazard Mater ; 452: 131286, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37001209

RESUMEN

As a novel strategy, peracetic acid (PAA) based advanced oxidation processes (AOPs) are being used in micropollutant elimination due to their high oxidation and low toxicity. In this study, Co2Ca1Al1-LDO as a kind of layered double oxides (LDOs) was successfully synthesized, and it is the first time to apply Co2Ca1Al1-LDO for activating PAA. The Co2Ca1Al1-LDO/PAA system showed excellent removal efficiencies for various micropollutants with removal ratios ranging from 90.4% to 100% and k values from 0.087 min-1 to 0.298 min-1. In the degradation period, various reactive oxygen species (ROS) are involved in the system, while organic radicals (R-O•) with a high concentration of 5.52 × 10-13 M are the dominant ROS in the contaminants degradation process. Compared to other ROS, R-O• had the largest contribution ratio (more than 85%) to pollutant degradation. Further analysis demonstrated that C1, C2, C3, C4, C5, C6 and N11 concentrated on the aniline group of SMX are the main attack sites based on the density functional theory (DFT) results, which is consistent with the degradation products. The toxicity of contaminants was obviously reduced after removing in this system. Furthermore, Co2Ca1Al1-LDO showed good reusability and stability, and Co2Ca1Al1-LDO/PAA system had excellent removal ability in actual water bodies containing inorganic anions, showing good application potential. Importantly, this study explored the feasibility of applying LDO catalysts in PAA-based AOPs for micropollutants elimination, providing new insights for subsequent research.

15.
Water Res ; 232: 119666, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36731206

RESUMEN

As an oxidant, peracetic acid (PAA) is gradually applied in advanced oxidation processes (AOPs) for pollutants degradation due to its high oxidation and low toxicity. In this study, the prepared Co2Fe1-LDH showed excellent PAA activation ability for efficient degradation of various pharmaceuticals with a removal efficiency ranging from 82.3% to 100%. Taking sulfamethoxazole (SMX) as a model pharmaceutical, it's found that organic radical (R-O•) with high concentration of 5.27 × 10-13 M is the dominant ROS responsible for contaminants degradation. Further analysis demonstrated that bimetallic synergistic effect between Co and Fe can improve electron transfer ability of Co2Fe1-LDH, resulting in the accelerated conversion of Co from +3 to +2 valence state with a high reaction rate (4.3 × 101-1.483 × 102 M-1 s-1) in this system. Density functional theory (DFT) reveals that C1, C3, C5 and N11 with higher ƒ0 and ƒ-values concentrated on aniline group of SMX are the main attack sites, which is consistent with the results of degradation products. Besides, Co2Fe1-LDH/PAA system can effectively reduce biological toxicity after reaction, due to lower biotoxicity of degradation products and the carbon sources provided by PAA. In application, Co2Fe1-LDH/PAA system was capable of resisting the influence of water matrix and effectively removing pollutants in actual hospital wastewater. Importantly, this study comprehensively evaluated the ability of Co2Fe1-LDH/PAA system to remove organics and improve the biodegradability of actual hospital wastewater, providing guidance for application of PAA activation system.


Asunto(s)
Ácido Peracético , Contaminantes Químicos del Agua , Aguas Residuales , Peróxido de Hidrógeno , Sulfametoxazol , Oxidación-Reducción , Preparaciones Farmacéuticas
16.
Environ Technol ; 44(22): 3382-3392, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35332842

RESUMEN

In order to treat domestic wastewater containing phosphorus and chemical oxygen demand (COD), the new technology of Sinusoidal Alternating Current (AC) Fenton Oxidation-Coagulation (SACFOC) was used to improve the removal efficiency (Re) and reduce energy consumption (EEC). The morphology, elemental composition, crystal structure and functional groups of the sludge were characterised by Scanning Electron Microscope (SEM), Energy-dispersive X-ray Spectroscopy (EDS), X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The results show that total phosphorus removal efficiency {Re(TP)} and removal efficiency of organic matter {Re(COD)} can reach 97.56% and 87.77%, respectively, but EEC is only 0.09 kWh·m-3 under the optimum conditions of pH0 = 3, current density (j) = 0.5 A·m-2, c0(TP) = 18 mg·dm-3, c0(COD) = 300 mg·dm-3, c0(H2O2) = 0.06 mol·dm-3, t = 45 min. As compared with direct current (DC) Fenton Oxidation-Coagulation (DCFOC), the COD removal efficiency of SACFOC treatment was improved by 37%, but the energy consumption was reduced by 45%. The degradation process of total phosphorus and COD by SACFOC abides by the quasi-first-order kinetic model. The process of SACFOC includes double effects of electrocoagulation of iron sol by electrolysis and degrade COD by oxidation of formed hydroxyl radicals (·OH) in wastewater, which improves removal efficiency of total phosphorus and COD in wastewater. Our research findings will provide technical guidance and a theoretical basis for the simultaneous treatment of wastewater containing phosphorus and COD applying SACFOC process.


Asunto(s)
Eliminación de Residuos Líquidos , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , Peróxido de Hidrógeno/química , Fósforo , Análisis de la Demanda Biológica de Oxígeno
17.
J Environ Sci (China) ; 124: 823-834, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36182186

RESUMEN

Electrocoagulation (EC) has been widely used to treat the heavy metal wastewater in industry. A novel process of sinusoidal alternating current electrocoagulation (SACC) is adopted to remove Ni2+ in wastewater in this study. The morphology of precipitates and the distribution of the main functional iron configurations were investigated. Ferron timed complex spectroscopy can identify the monomeric iron configurations [Fe(a)], oligomeric iron configurations [Fe(b)] and polymeric iron configurations [Fe(c)]. The optimal operating conditions of SACC process were determined through single-factor experiments. The maximum Ni2+ removal efficiency [Re(Ni2+)] was achieved under the conditions of pH0=7, current density (j) = 7 A/m2, electrolysis time (t) = 25 min, c0(Ni2+) = 100 mg/L. At pH=7, the proportion of Fe(b) and Fe(c) in the system was 50.4 at.% and 23.1 at.%, respectively. In the SACC process, Fe(b) and Fe(c) are the main iron configurations in solution, while Fe(c) are the vast majority of the iron configurations in the direct current electrocoagulation (DCC) process. Re(Ni2+) is 99.56% for SACC and 98.75% for DCC under the same optimum conditions, respectively. The precipitates produced by SACC have a high proportion of Fe(b) configurations with spherical α-FeOOH and γ-FeOOH structures which contain abundant hydroxyl groups. Moreover, it is demonstrated that Fe(b) has better adsorption capacity than Fe(c) through adsorption experiments of methyl orange (MO) dye. Fe(a) configurations in the homogeneous solution had no effect on the removal of nickel.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Purificación del Agua , Electrocoagulación , Electrodos , Concentración de Iones de Hidrógeno , Hierro/química , Níquel , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
18.
Micromachines (Basel) ; 15(1)2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38276838

RESUMEN

Embedded liquid cooling is a preferred solution for dissipating the heat generated by high-power chips. The cooling capacity and pump power consumption of embedded liquid cooling heat sinks differ significantly between different structures. To achieve an accurate match between cooling capacity and heat dissipation requirements, the selection of a liquid-cooled heat sink should be carefully considered in conjunction with the heat dissipation needs of heat sources in real-world thermal management issues. Based on the manufacturing limitations on chip temperature and microchannel pressure, a composite performance index function was developed to assess the cooling capacity and cooling cost of the heat sink. This allowed for the establishment of an evaluation standard to determine the suitability of embedded liquid cooling and heat sink for the heat source. In this study, the suitability of four microchannel heat sinks with the same feature length and fin volume was evaluated under various thermal load conditions. The results show that the best-suited heat sink changes with variations in the thermal load of the chip. In the example, when the heat source was homogeneous at 100 W, the circular section pin fins have an optimal suitability of 0.928 for Re = 500. When the heat source was a heterogeneous heat source with a power of 100 W, the value of Θ was found to be 0.389. Additionally, the optimal suitability of drop section pin fins for Re = 971.5 was determined to be 0.862.

19.
Micromachines (Basel) ; 13(12)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36557435

RESUMEN

A three-dimensional convective heat transfer model of a microchannel pin-fin hybrid heat sink was established. Considering the non-uniform heat generation of 3D stacked chips, the splitting distance of pin-fins was optimized by minimizing the maximum heat sink temperature under different heat fluxes in the hotspot, the Reynolds numbers at the entrance of the microchannel, and the proportions of the pin-fin volume. The average pressure drop and the performance evaluation criteria were considered to be the performance indexes to analyze the influence of each parameter on the flow performance and comprehensive performance, respectively. The results showed that the maximum temperature of the hybrid heat sink attained a minimum value with an increase in the splitting distance. The average pressure drop in the center passage of the microchannel first increased and then decreased. Furthermore, the optimal value could not be simultaneously obtained with the maximum temperature. Therefore, it should be comprehensively considered in the optimization design. The heat flux in the hotspot was positively correlated with the maximum heat sink temperature. However, it had no effect on the flow pressure drop. When the Reynolds number and the pin-fin diameter increased, the maximum heat sink temperature decreased and the average pressure drop of the microchannel increased. The comprehensive performance of the hybrid heat sink was not good at small Reynolds numbers, but it significantly improved as the Reynolds number gradually increased. Choosing a bigger pin-fin diameter and the corresponding optimal value of the splitting distance in a given Reynolds number would further improve the comprehensive performance of a hybrid heat sink.

20.
ACS Omega ; 7(47): 42939-42948, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36467920

RESUMEN

Poly-l-lactic acid (PLLA) is a biodegradable polymer with great mechanical properties and good transparency, but its low crystallization rate greatly limits its application. Hyperbranched polyesters (HBPs) modified carbon nanotubes (CNTs) are an ideal nucleating agent to prove the crystallization of PLLA. To compare different terminal group HBPs' effect on the modification of CNTs and the crystallization of PLLA, through the condensation reaction and amidation reaction, CNTs-H202 and CNTs-N102 were prepared, respectively. The modification was confirmed by Fourier-transform infrared (FTIR) spectroscopy, X-ray electron spectroscopy (XPS), and thermogravimetric analysis (TGA). Using transmission electron microscopy (TEM), we observed the changes on the surface of modified CNTs. PLLA/CNT composites were prepared, and differential scanning calorimetry (DSC) was used to investigate the crystallization behavior of the composites. The mechanical properties of PLLA/CNT composites were investigated as well. The results showed that the modified CNTs had a better promotion on PLLA crystallization and mechanical properties than the unmodified CNTs. CNTs-N102 had a slight advantage on the promotion on PLLA crystallization, which was caused by the lower grafting rate of HBP N102, and CNTs-H202 had a better promotion on the mechanical properties of PLLA, which was caused by the better compatibility with PLLA. In conclusion, hydroxy-terminated HBP is a better CNT modified material than amino-terminated HBP.

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