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1.
Anal Chem ; 95(36): 13456-13462, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37624577

RESUMO

Artificial solid-state nanochannels have garnered considerable attention as promising nanofluidic tools for ion/molecular detection, DNA sequencing, and biomimicry. Recently, nanofluidic devices have emerged as cost-effective detection tools for heavy metal ions by modifying stimuli-responsive materials. In this work, high-purity glycyl-l-histidyl-l-lysine (GHK) peptide is synthesized by using 7-diphenylphosphonooxycoumarin-4-methanol (DPCM) as a protecting group and auxiliary carrier by homogeneous synthesis of photocleavable groups. Subsequently, we developed a GHK-modified asymmetric nanochannel nanofluidic diode by covalently attaching the GHK peptide to the inner surface of the nanochannels. This modification facilitated specific recognition and ultra-trace level detection of Cu2+ ions, achieving a detection limit of 10-15 M. Due to the robust complexing ability between Cu2+ and GHK peptide, the GHK-modified asymmetric nanochannels can form GHK-Cu complexes on the inner surface of nanochannels when Cu2+ passes through the nanochannels. This results in changes of current-potential (I-V) properties, which facilitated Cu2+ detection. Theoretical calculations confirmed the high affinity of the GHK peptide for Cu2+, thereby ensuring excellent Cu2+ selectivity. To evaluate the applicability of our system for detecting Cu2+ in real-world scenarios, we analyzed the concentration of Cu2+ in tap water. The GHK-Cu complexes could be dissociated by adding EDTA to the solution, enabling the regeneration and reuse of this ultrasensitive and label-free Cu2+ detection system using GHK-modified asymmetric multi-nanochannels. We anticipate that the GHK-modified asymmetric nanochannels will find future applications in the label-free detection of Cu2+ in domestic water.

2.
Environ Res ; 216(Pt 4): 114819, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36395859

RESUMO

The huge application of synthetic dyes caused a severe impact in the environment. In the present study, a physico-chemical strategy of heterogeneous-Fenton catalyzed by the natural ferrous ore has been established for toxic chemical degradation, of which the complex and high-expense repetitive pH adjustment procedures were escaping. And this natural heterogeneous catalyst also could be recycled and sustainable for toxic substances treatment involved in synergetic adsorption and oxidation. The siderite, served as an adsorbent and catalyst for the degradation of methylene blue (MB). Siderite exhibited a better adsorption capacity with a saturated adsorption capacity of ∼11.08 mg/g. Batch adsorption experiments have verified that adsorption rate and adsorption equilibrium followed pseudo-second-order rate model and Langmuir isotherm equation, respectively. The combination with H2O2, showed significant enhancement of MB degradation without any pH adjustment. The effect of siderite dosage, H2O2 dosage, MB concentration, initial pH, and reaction temperature on MB degradation was investigated, which also has indicated the excellent catalytic performance of siderite. About 99.71% of MB was degraded in 480 min with initial pH of 7.0, reaction temperature of 25 °C, siderite, and H2O2 dosage of 2.5 g/L and 122.38 mM, respectively. It was found that siderite could be reused and remained high degradation efficiency on MB after 5 times reutilization, which also could demonstrate the sustainable and effective process to degrade organic pollution. The generation of reactive species including ·OH and O2·- have been confirmed based on scavenger test and electron spin resonance (ESR) analysis, which was dominated by heterogeneous reaction. The possible degradation mechanisms of MB have been predicted based on spectrum scanning and GC-MS analysis. Moreover, acute toxicity assessment with marine photobacterium Vibrio fisheri was conducted to investigate the toxicity change in the adsorption/oxidation coupled process. This sustainable heterogeneous-Fenton technology has been verified as a promising and applicable process for toxic organic chemicals removal due to effective mineralization and detoxification assisted with the natural ore mineral through the simple operation and mild condtions.


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Azul de Metileno/química , Peróxido de Hidrogênio , Poluentes Químicos da Água/química , Cinética , Adsorção , Catálise
3.
Environ Res ; 205: 112430, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34843722

RESUMO

Carbon neutrality has been received more attention and emerged in wastewater treatment processes. Due to the development of treating technologies with the rising of new-emerging pollutants, the coupled chemical processes also should remain current for the goal of carbon-neutral operation. Among of those updated strategies, several advanced oxidation processes (AOPs) based on dithionite (DTN, S2O42-), a common water treatment agent, have been established for refractory organic contaminations removal. However, in terms of DTN detection, the traditional formol-titration method has several application limits including the low detection sensitivity and high consumption of formaldehyde. In this study, compared with traditional method, a low energy consumption technology has been developed based on the potassium ferricyanide with the carbon consumption decreasing by about 5 times. Moreover, detection limit of DTN (mmol/L level) also was lower than the titration method. The method was established based on the fact that every 1 mol of DTN can react with 2 mol [Fe(CN)6]3- under alkaline condition. According to that potassium ferricyanide (K3 [Fe(CN)6]) has the maximum absorption at 419 nm wavelength, a fitting equation based on the linear relationship between the absorbance variation of K3 [Fe(CN)6] and DTN amount in the ranges of 0-30 µmol with the detection limit of 0.6 µmol was established with the determination coefficient of 0.99935. It was found that there was no obvious influence of the ubiquitous foreign species with the amount lower than 6 mM, 4 mM, 6 mM, 4 mM and 1 mg/L for Cl-, HCO3-, NO3-, SO42- and NOM, respectively. Moreover, methanol and tert-butanol were employed to verify the influence of the presence of organic matters on the determination of DTN and no impact was observed in this study. The proposed method provides a new way for DTN detection with stable and countable performance in the related AOPs with the low electric energy and carbon source consumption and high detection efficiency.


Assuntos
Ferricianetos , Tecnologia , Ditionita , Oxirredução , Espectrofotometria/métodos
4.
J Environ Manage ; 321: 116034, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36027733

RESUMO

In this study, dithionite (DTN) was used to degrade Tetrabromobisphenol A (TBBPA), a widely applied brominated flame retardants, under anaerobic conditions with the reaction terminator of nitrate. The optimization of reaction parameters including TBBPA concentration, DTN concentration and pH value were conducted by response surface methodology (RSM) based on central composite design (CCD). The degradation process could be simulated accurately by a quadratic model with the correlation coefficient R2 of 0.9550. The interaction between pH and DTN concentration was significant with the p-value of 0.0017. Moreover, the maximum TBBPA removal was 87.6 ± 3.2% and obtained at TBBPA concentration of 2.00 µM, the DTN concentration of 322.31 µM, and the pH of 6.14 under anaerobic conditions. It was found that the factors influenced TBBPA removal followed the order: pH > DTN concentration > TBBPA concentration. The major active products from DTN are SO32- and S2O32-. In addition, different inhibitions of natural water matrix including chloride, bicarbonate, sulfide and humic acid on TBBPA degradation had been confirmed. According to the identified six intermediates via gas chromatography-mass spectrometry (GC-MS), two steps of the degradation pathways were speculated, including the breakage of C-Br bond and C-C bond. This study provides a convenient way to degrade TBBPA.


Assuntos
Retardadores de Chama , Bifenil Polibromatos , Anaerobiose , Ditionita , Retardadores de Chama/metabolismo , Bifenil Polibromatos/química , Bifenil Polibromatos/metabolismo
5.
Environ Geochem Health ; 44(11): 3837-3851, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34713368

RESUMO

Eutrophication has become a great concern in recent years with the algae blooms in source water resulting in a serious threat posing to the safety of drinking water. Chlorine dioxide (ClO2) has been served as an alternative oxidant for preoxidation or disinfection during drinking water treatment process due to its high oxidation efficiency and low risk of organic by-products formation. However, the generation of inorganic by-products including chlorite (ClO2-) and chlorate (ClO3-) has become a potential problem when applied in drinking water treatment. In this study, ClO2 preoxidation-assisted coagulation/precipitation process was applied to improve the raw water quality, especially algae, turbidity, chemical oxygen demand (CODMn), and UV254, and explore the formation mechanisms of inorganic by-products. It was found that the polymeric aluminum chloride (PAC) and ClO2 have shown the best raw water treatment performance with the optimal dosage of 10 mg/L and 0.8 mg/L, respectively. Moreover, the initial pH also has exhibited a notable influence on pollutants treatment and by-products generation. Due to the adverse influence of algae and natural organic matters (NOM) and the generation of by-products, it was significant to investigate their inhibition effect on the water quality and the production of ClO2- and ClO3- in the ClO2 preoxidation-assisted coagulation/precipitation process. Moreover, it was applicable of this process to apply for the algae-containing raw water (calculated as Chl.a lower than 50 µg/L) treatment with the ClO2 dosage of less than 0.8 mg/L to achieve optimum treatment performance and minimum by-products generation.


Assuntos
Água Potável , Poluentes Ambientais , Purificação da Água , Cloratos , Cloreto de Alumínio , Purificação da Água/métodos , Óxidos , Oxirredução , Oxidantes , Cloro
6.
Small ; 17(24): e2100969, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33938137

RESUMO

Solar-driven evaporation is regarded as a sustainable wastewater treatment strategy for clean water recovery and salt condensation. However, achieving both high evaporation rate and long-term stability remain challenging due to poor thermal management and rapid salt accumulation and blocking. Here, a T-shape solar-driven evaporator, composed of a surface-carbonized longitudinal wood membrane (C-L-wood) is demonstrated as the top "" for solar harvesting/vapor generation/salt collection and another piece of natural L-wood as the support "" for brine transporting and thermally insulating. The horizontally aligned micro-channels of C-L-wood have a low perpendicular thermal conductivity and can effectively localize the thermal energy for rapid evaporation. Meanwhile, the brine is guided to transport from the support L-wood ("") to the centerline of the top evaporator and then toward the double edge (""), during which clean water is evaporated and salt is crystallized at the edge. The T-shape evaporator demonstrates a high evaporation rate of 2.43 kg m-2 h-1 under 1 sun irradiation, and is stable for 7 days of the outdoor operation, which simultaneously realizes clean water evaporation and salt collection (including Cu2+ , CrO42- , Co2+ ), and achieves zero-liquid discharge. Therefore, the T-shape design provides an effective strategy for high performance wastewater treatment.


Assuntos
Energia Solar , Purificação da Água , Luz Solar , Água , Madeira
7.
Water Sci Technol ; 79(3): 573-579, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30924812

RESUMO

Persulfate-based advanced oxidation has been widely applied in environmental remediation for degrading contaminants. In recent years, numerous kinds of organic analytes including pesticides, dyes and pharmaceuticals, have emerged and related researches on the activation methods, the mechanism and the application have been performed. The activation is critical in persulfate-based advanced oxidation because the persulfate alone has a weaker oxidation potential to degrade these organic pollutants. Hence various activation methods have been extensively investigated to achieve a higher oxidation efficiency. These novel methods are gradually expanding the applicability and practicality. This review focuses on the classification of the different activation methods based on whether it is related to the substances or not. The effect of the environmental conditions (solution pH, dosage and the co-existing substance) on the oxidation capacity are also discussed.


Assuntos
Recuperação e Remediação Ambiental , Sulfatos/química , Poluentes Químicos da Água/química , Oxirredução
8.
Water Sci Technol ; 79(3): 589-596, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30924814

RESUMO

Heavy metal contamination from electroplating wastewater is a serious risk to terrestrial life and public health. The complexed metal cannot be effectively removed by traditional precipitation without decomplexing. In this work, four ozone-based advanced oxidation processes, O3, O3/H2O2, O3/UV and O3/H2O2/UV to decomplex electroplating wastewater were investigated and their performance compared. Ethylenediaminetetraacetic acid (EDTA) and citric acid are the most common components of electroplating wastewater. They were used as representatives to study the decomplexation and mineralization of complexes in the ozone-based advanced oxidation processes. Among all, the highest degradation and mineralization efficiency of EDTA occurred in O3/UV and was 65% and 53% in 60 min, respectively. For citric acid, the highest degradation (77%) and mineralization (56%) efficiency was observed in the O3/H2O2/UV process. This indicates that selection of the advanced oxidation process is determined by the target contaminant.


Assuntos
Galvanoplastia , Ozônio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Peróxido de Hidrogênio , Metalurgia , Oxirredução , Raios Ultravioleta , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água
9.
Zhongguo Zhong Yao Za Zhi ; 39(18): 3487-92, 2014 Sep.
Artigo em Zh | MEDLINE | ID: mdl-25532382

RESUMO

To analyze the reality of ectopic pregnancy patients' clinical medication, find out the association rules of chemical medicine and traditional Chinese medicine, HIS data from 15 grade III-A general hospitals were collected, descriptive statistic methods and association rules were used in analysis of the data. The results showed that the most commonly used western medicine types were antibiotics,hemostatic medicine and killing embryo medicine. The most commonly used traditional Chinese medicine types were heat clearing and detoxicating drugs, promoting blood circulation and removing blood stasis drugs, tonifying Qi and blood drugs. The common combinations of western medicine and Chinese medicine were heat clearing and detoxicating drug add antibiotics, heat clearing and detoxicating drug add hemostatic medicine, promoting blood circulation and removing blood stasis drug add antibiotics, tonifying Qi and blood drug add antibiotics. In conclusion, the medicine types of ectopic pregnancy were concentrated. For conbined treatment of traditional Chinese medicine and western medicine, heat clearing and detoxicating, tonic righting, promoting blood circulation and removing blood stasis treatment were often used on the basis of anti-inflammatory, killing embryo and hemostasis.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Gravidez Ectópica/tratamento farmacológico , Feminino , Sistemas de Informação Hospitalar , Humanos , Gravidez
10.
Zhongguo Zhong Yao Za Zhi ; 39(18): 3527-34, 2014 Sep.
Artigo em Zh | MEDLINE | ID: mdl-25532389

RESUMO

OBJECTIVE: To study the characteristics and regular pattern of the medicine in common use and combined medication in patients of acute pancreatitis in real world. METHOD: Collect the information of 5 433 acute pancreatitis patients in 19 grade IIIA general hospitals in China, analysis by descriptive statistics and association rule. RESULT: In the 5 433 patients of acute pancreatitis, the glycyrrhizic acid injection and somatostatin are the frequency top used Chinese traditional and western medication. Glycyrrhizic acid injection, somatostatin and insulin are the frequency top used drug combination pattern. CONCLUSION: The Chinese and western integrative medicine drug use pattern are accord with the clinical guideline of acute panceatitis. The hepatic and renal function, blood routine and coagulation function should be monitored when the medicines are used.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Pancreatite/tratamento farmacológico , Adolescente , Adulto , Idoso , Anti-Inflamatórios/uso terapêutico , Quimioterapia Combinada , Feminino , Ácido Glicirrízico/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Somatostatina/uso terapêutico , Adulto Jovem
11.
Zhongguo Zhong Yao Za Zhi ; 39(18): 3448-53, 2014 Sep.
Artigo em Zh | MEDLINE | ID: mdl-25532376

RESUMO

Viral hepatitis was the most common infectious disease in china. But the diagnosis and treatment were varied because the viral hepatitis patients were hospitalized in different kinds of hospital such as infectious disease hospital, general hospital and Chinese medical hospital. It was necessary to know clinical characters and information of viral hepatitis patients in different hospitals. The general information, subtype distribution, prognosis, complication, medication and relations of onset with solar term from 41 180 viral hepatitis patients based on HIS data were analyzed. It was found that the age of patients between 18 to 59 years old was most; most patients were males. The national basic medical insurance was the most type of payment. The outcome of viral hepatitis in the youth and female were better than that in the old and male. Acute hepatitis was easer to restore than chronic hepatitis. Liver cirrhosis and hepatocellular carcinoma were the two most complications. The peak of onset was during summer solstice, slight heat and great heat. The most common Chinese medicine was Diammonium glycyrrhizinate and the most common western medicine was reduced glutathione. The combination of D. glycyrrhizinate with reduced glutathione, polyene phosphatidylcholine and thymosin was the main pattern. But It was not knew if the combination of western and Chinese medicine was the most effective therapy to protect liver function. It was necessary to take deeply research of the relationship between the combination therapy and their effectiveness.


Assuntos
Antivirais/uso terapêutico , Hepatite Viral Humana/tratamento farmacológico , Adolescente , Adulto , Idoso , Feminino , Glutationa/uso terapêutico , Ácido Glicirrízico/uso terapêutico , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Zhongguo Zhong Yao Za Zhi ; 39(18): 3541-5, 2014 Sep.
Artigo em Zh | MEDLINE | ID: mdl-25532391

RESUMO

Nineteen comprehensive hospital information system (HIS) data are collected. Cleaning up the database, then analysis the patients' information. Using the basic description method and association rules to analysis the data. Analysis the data come from HIS database, we found that in 2 110 patients, main five complications are Henoch Schonlein purpura nephritis, upper respiratory tract infections, renal insufficiency, virus infection and glomerulonephritis (chronic), treatment of chemical drugs with sugar cortical hormone and anti infection drugs, such as intravenous input cephalosporin drugs. Traditional Chinese medicine with blood-activating and stasis-resolving medicine, heat clearing and detoxifying medicine. Combination scheme with blood-activating and stasis-resolving medicine joint glucocorticoid, followed by blood-activating and stasis-resolving medicine combined antiallergic drugs, heat-clearing and detoxifying medicine combined antiallergic drugs. Promoting blood circulation and removing blood stasis is an important part of traditional Chinese medicine treatment in patients with Henoch Schonlein purpura.


Assuntos
Vasculite por IgA/diagnóstico , Vasculite por IgA/tratamento farmacológico , Medicina Tradicional Chinesa/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antialérgicos/uso terapêutico , Criança , Pré-Escolar , Feminino , Glucocorticoides/uso terapêutico , Hospitais , Humanos , Vasculite por IgA/complicações , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
J Colloid Interface Sci ; 667: 212-222, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38636223

RESUMO

The application of supermolecular naonostructures in the photocatalytic carbon dioxide reduction reaction (CO2RR) has attracted increasing attentions. However, it still faces significant challenges, such as low selectivity for multi-electron products and poor stability. Here, the cuprous oxide (Cu2O)-modified zinc tetraphenylporphyrin ultrathin nanosheets (ZnTPP NSs) are successfully constructed through the aqueous chemical reaction. Comprehensive characterizations confirm the formation of type-II heterojunction between Cu2O and ZnTPP in Cu2O@ZnTPP, and the electron transfer from Cu2O to ZnTPP through the Zn-O-Cu bond under the static contact. Under the visible-light irradiation (λ > 420 nm), the optimized Cu2O@ZnTPP sample as catalyst for photocatalytic CO2RR exhibits the methane (CH4) evolution rate of 120.9 µmol/g/h, which is âˆ¼ 4 and âˆ¼ 10 times those of individual ZnTPP NSs (28.0 µmol/g/h) and Cu2O (12.8 µmol/g/h), respectively. Meanwhile, the CH4 selectivity of âˆ¼ 98.7 % and excellent stability can be achieved. Further experiments reveal that Cu2O@ZnTPP has higher photocatalytic conversion efficiency than Cu2O and ZnTPP NSs, and the photoinduced electron transfer from ZnTPP to Cu2O can be identified via the path of ZnTPP→ (ZnTPP•ZnTPP)*→ ZnTPP-→ Zn-O-Cu â†’ Cu2O. Consequently, Cu2O@ZnTPP exhibits a shorter electron-hole separation lifetime (3.3 vs. 9.3 ps) and a longer recombination lifetime (23.1 vs. 13.4 ps) than individual ZnTPP NSs. This work provides a strategy to construct the organic nanostructures for photocatalytic CO2RR to multi-electron products.

14.
Anal Methods ; 16(17): 2654-2660, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38623688

RESUMO

Nickel stands out as one of the prevalent heavy metal ionic pollutants found in water. It is urgent to devise a simple, efficient, budget-friendly, highly-selective and proficient method for detecting Ni(II). This work reports an approach to design a nanofluidic diode for the ultrasensitive and label-free detection of nickel ions based on layer-by-layer assembly of polyarginine (PA) and polyglutamic acid (γ-PGA) on the inner surface of asymmetric nanochannels. We can tune the adsorption/desorption characteristics of the asymmetric nanochannels for Ni2+ by adjusting the pH changes, i.e., the PA-γ-PGA modified nanochannels adsorb Ni2+ at pH 6 and desorb at pH 3 in aqueous solution. This pivotal adjustment facilitates the reusable and specific detection of nickel ions with a detection limit of 1 × 10-8 M. Moreover, the system demonstrates commendable stability and recyclability, enhancing its practical applicability. This innovative system holds promise for recognizing and detecting nickel ions in diverse environments such as water, blood, and cells. The robust performance and adaptability of our proposed system instill confidence in its potential for future applications.

15.
Environ Pollut ; 339: 122736, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37838321

RESUMO

Recently, it has been reported that chlorine dioxide (ClO2) and (bi)sulfite/ClO2 showed excellent performance in micropollutant removal from water; however, the degradation mechanisms and application boundaries of the two system have not been identified. In this study, bisphenol A (BPA) was chosen as the target contaminant to give multiple comparisons of ClO2 and S(IV)/ClO2 process regarding the degradation performance of contaminant, generation of reactive species, transformation of products and toxicity variation. Both ClO2 and S(IV)/ClO2 can degrade BPA within 3 min. The BPA degradation mechanism was mainly based on direct oxidation in ClO2 process while it was attributed to radicals (especially SO4·-) generation in S(IV)/ClO2 process. Meanwhile, the effect of pH and coexisting substances (Cl-, Br-, HCO3- and HA) were evaluated. It was found that ClO2 preferred the neutral and alkaline condition and S(IV)/ClO2 preferred the acidic condition for BPA degradation. An unexpected speed-up of BPA degradation was observed in ClO2 process in the presence of Br-, HCO3- and HA. In addition, the intermediate products in BPA degradation were identified. Three exclusive products were found in ClO2 process, in which p-benzoquinone was considered to be the reason of the acute toxicity increase in ClO2 process.


Assuntos
Compostos Clorados , Poluentes Químicos da Água , Purificação da Água , Óxidos/toxicidade , Óxidos/química , Compostos Clorados/toxicidade , Compostos Clorados/química , Fenóis/toxicidade , Oxirredução , Cloro/química , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
16.
J Colloid Interface Sci ; 638: 123-134, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36736114

RESUMO

The zinc-based photocatalysts for CO2 reduction have attracted increasing attention, however, usually exhibit low CO2-to-CH4 selectivity. Here, the graphene oxide (GO)-coated zinc tetraphenylporphyrin (ZnTPP/GO) nanocomposites are successfully synthesized through a simple method. It is found that with the increase of GO content, the crystallinity of ZnTPP nanocrystals enhances with the size decrease, and then the light absorption can easily match with the solar spectrum. The optimal ZnTPP/GO sample exhibits the CH4 evolution rate of 41.6 µmol g-1 h-1 and CH4 selectivity of >95%, which are higher than those of ZnTPP nanocrystals (7.8 µmol g-1 h-1 and 50.3%). The systematic characterizations confirm that the generation of axial coordinated ZnOC bonds between ZnTPP and GO plays a key role in the formation of ZnTPP/GO nanostructure and their synergic effect on photocatalytic CO2 reduction. The encapsulation of GO on ZnTPP nanocrystals not only promotes the CO2 adsorption, interfacial reaction, and stability, but also accelerates the separation of photoinduced carriers on ZnTPP (0.1 ps vs. 425.9 ps), the transportation from ZnTPP to GO (2.3 ps vs. 83.6 ps), and their final enrichment on GO. This work provides a new strategy to apply graphene and organic nanomaterials in artificial photosynthesis.


Assuntos
Grafite , Nanocompostos , Óxido de Zinco , Zinco , Dióxido de Carbono
17.
Macromol Biosci ; 23(7): e2200559, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36945731

RESUMO

Currently, gastrointestinal bleeding in the colon wall and the small bowel is diagnosed and treated with endoscopes. However, the locations of this condition are often problematic to treat using traditional flexible and tethered tools. New studies commonly consider untethered devices for solving this problem. However, there still exists a gap in the extant literature, and more research is needed to diagnose and deliver drugs in the lower gastrointestinal tract using soft robotic carriers. This paper discusses the development of an untethered, magnetically-responsive bio-inspired soft carrier. A molding process is utilized to produce prototypes from Diisopropylidene-1,6-diphenyl-1,6-hexanediol-based Polymer with Ethylene Glycol Dimethacrylate (DiAPLEX) MP-3510 - a shape memory polymer with a low transition temperature to enable the fabrication of these carriers. The soft carrier design is validated through simulation results of deformation caused by magnetic elements embedded in the carrier in response to an external field. The thermal responsiveness of the fabricated prototype carriers is assessed ex vivo and in a phantom. The results indicate a feasible design capable of administering drugs to a target inside a phantom of a large intestine. The soft carrier introduces a method for the controlled release of drugs by utilizing the rubbery modulus of the polymer and increasing the recovery force through magnetic actuation.


Assuntos
Sistemas de Liberação de Medicamentos , Polímeros , Temperatura , Sistemas de Liberação de Medicamentos/métodos , Excipientes , Fármacos Gastrointestinais , Fenômenos Magnéticos
18.
Environ Pollut ; 318: 120925, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36566677

RESUMO

Microplastics (MPs), an emerging pollutant, have been increasingly raising concern due to the potential impacts on aquatic organisms. Moreover, the environmental aged MPs always exhibit different environmental behavior and interaction effect with organic pollutants from virgin MPs. In this work, the single and combined toxicity impact on Chlorella pyrenoidosa, a symbiont representative, has been investigated between MPs (e.g., polyamide microplastic (PA6), 75 µm) and organic pollutants (e.g., sulfamethoxazole (SMX) and dicamba (DCB)). Growth inhibition, chlorophyll accumulation, superoxide dismutase (SOD), malondialdehyde (MDA), and catalase (CAT) were investigated with the primary or UV-aged PA6. Above 0.5 g/L PA6 (primary or UV-aged) inhibited cell growth and chlorophyll accumulation after 96 h cultivation as compared with the control. Besides, the inhibition impacts have enhanced as the UV-aging time extending in the single PA6 systems. The algae growth inhibition rate after 96 h cultivation in both the system i.e., single (PA6: 6.9%) and combined (PA6-SMX: 14.2%, PA6-DCB: 14.9%) was slightly lower than that of exposing in organic pollutants alone (SMX: 23.9%, DCB: 25.0%), while the chl. b concentration in 60 days UV-aged PA6 combined with SMX (1.19 mg/L) or DCB (1.40 mg/L) systems were higher than in single SMX (1.04 mg/L) or DCB (1.33 mg/L) system. In addition, there were several differences of the cellular oxidative stress in the combined system of SMX and DCB. Specially, it was not noticeable of three enzymatic activities for SMX exposing in the presence of primary or UV-aged PA6. While SOD, CAT, and MDA activities was obviously increasing after exposing in PA6 and DCB combined system, indicating the significant synergistic effect on algae cells damage. This research verified the remarkable combined toxicity between UV-aged MPs and organic pollutants on microalgae.


Assuntos
Chlorella , Microalgas , Poluentes Químicos da Água , Clorofila , Microplásticos/toxicidade , Plásticos/farmacologia , Superóxido Dismutase , Poluentes Químicos da Água/análise , Raios Ultravioleta
19.
Environ Pollut ; 316(Pt 2): 120579, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336186

RESUMO

Tetrabromobisphenol A (TBBPA), a representative brominated flame retardant (BFR), generally could be debrominated and degraded effectively in photolysis systems with the high energy consumption. In this study, the novel sulfate radical (SO4•-) generation resource of dithionite (S2O42-), activated by the common transition metal of Fe3+, has been applied for establishing an innovative homogeneous advance treatment system for BFR treatment in water. When coupling Fe3+ with S2O42-, TBBPA degradation efficiency could be remarkably improved from 38.7% to 93.8% with the debromination and mineralization efficiency of 83.9% and 18.5% in 60 min, respectively. The primary reactive species also have been identified as SO3•-, SO4•- and •OH responsible for TBBPA treatment and the contributions of SO4•- and •OH have been calculated as 43.8% and 28.4% for TBBPA degradation, respectively. In Fe3+/S2O42- system, TBBPA was effectively degraded in a wide initial pH range (3.0-9.0), whose activation energy was calculated as 32.01 kJ mol-1. Due to the only operation of reagents dosing, the energy consumption and cost could be decreasing significantly without any light energy input and reaction conditions (e.g., pH and dissolved oxygen) adjustment compared with the general photolysis process. Moreover, some possible degradation approaches of TBBPA also have been proposed via GC-MS including debromination, hydroxylation, methylation, and mineralization in Fe3+/S2O42- system. And these probable degradation pathways also have been confirmed with the decreased Gibbs free energy (ΔG) based on density functional theory (DFT). This study has revealed that it was promising of Fe3+/S2O42- system for BFRs degradation and detoxification efficiently through the simple operation and mild condtions.


Assuntos
Retardadores de Chama , Bifenil Polibromatos , Bifenil Polibromatos/metabolismo , Retardadores de Chama/metabolismo , Fotólise , Água
20.
STAR Protoc ; 4(3): 102392, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37393610

RESUMO

The lack of systems to automatically extract epidemiological fields from open-access COVID-19 cases restricts the timeliness of formulating prevention measures. Here we present a protocol for using CCIE, a COVID-19 Cases Information Extraction system based on the pre-trained language model.1 We describe steps for preparing supervised training data and executing python scripts for named entity recognition and text category classification. We then detail the use of machine evaluation and manual validation to illustrate the effectiveness of CCIE. For complete details on the use and execution of this protocol, please refer to Wang et al.2.


Assuntos
COVID-19 , Processamento de Linguagem Natural , Humanos , Idioma , COVID-19/epidemiologia
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