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1.
J Am Chem Soc ; 146(9): 6231-6239, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38386884

RESUMO

Acquiring a deep insight into the electron transfer mechanism and applications of one-dimensional (1D) van der Waals heterostructures (vdWHs) has always been a significant challenge. Herein, through direct observation using aberration-corrected transmission electron microscopy (AC-TEM), we verify the stable formation of a high-quality 1D heterostructure composed of PbI2@single-walled carbon nanotubes (SWCNTs). The phenomenon of electron transfer between PbI2 and SWCNT is elucidated through spectroscopic investigations, including Raman and X-ray photoelectron spectroscopy (XPS). Electrochemical testing indicates the electron transfer and enduring stability of 1D PbI2 within SWCNTs. Moreover, leveraging the aforementioned electron transfer mechanism, we engineer self-powered photodetectors that exhibit exceptional photocurrent and a 3-order-of-magnitude switching ratio. Subsequently, we reveal its unique electron transfer behavior using Kelvin probe force microscopic (KPFM) tests. According to KPFM, the average surface potential of SWCNTs decreases by 80.6 mV after filling. Theoretical calculations illustrate a charge transfer of 0.02 e per unit cell. This work provides an effective strategy for the in-depth investigation and application of electron transfer in 1D vdWHs.

2.
J Am Chem Soc ; 145(44): 24349-24357, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37883799

RESUMO

Understanding the interplay between the surface structure and the passivation materials and their effects associated with surface structure modification is of fundamental importance; however, it remains an unsolved problem in the perovskite passivation field. Here, we report a surface passivation principle for efficient perovskite solar cells via a facet-dependent passivation phenomenon. The passivation process selectively occurs on facets, which is observed with various post-treatment materials with different functionality, and the atomic arrangements of the facets determine the alignments of the passivation layers. The profound understanding of facet-dependent passivation leads to the finding of 2-amidinopyridine hydroiodide as the material for a uniform and effective passivation on both (100) and (111) facets. Consequently, we achieved perovskite solar cells with an efficiency of 25.10% and enhanced stability. The concept of facet-dependent passivation can provide an important clue on unidentified passivation principles for perovskite materials and a novel means to enhance the performance and stability of perovskite-based devices.

3.
J Org Chem ; 88(5): 2841-2850, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36812409

RESUMO

We demonstrated here an efficient synthetic method of carbazole derivatives from readily available N-arylnaphthalen-2-amines and quinone esters catalyzed by Brønsted acid. With this strategy, a series of carbazole derivatives were obtained in good to excellent yields (76 to >99) under mild conditions. Large scale reaction illustrated the synthetic utility of this protocol. Meanwhile, a series of C-N axially chiral carbazole derivatives were also constructed in moderate to good yields (36-89% yield) with moderate to excellent atroposelectivities (44-94% ee) by using chiral phosphoric acid as a catalyst, which provides a novel strategy for the atroposelective construction of C-N axially chiral compounds and a new member of the C-N atropisomers.

4.
Molecules ; 28(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513488

RESUMO

A catalyst-free aza-Michael addition/C(sp3)-O bond formation tandem reaction of substituted amino ferrocenes with quinone esters was developed, which provided a green and efficient strategy for the construction of a C(sp3)-O bond from C(sp3)-H, and a series of N-ferrocene-substituted benzodihydrooxazoles were smoothly produced in moderate to excellent yields (up to >99% yield). The mechanism experiments showed that quinone esters performed as both substrate and oxidant. The salient features of this transformation include good functional group tolerance, broad substrate scope and mild conditions.

5.
Cell Tissue Bank ; 21(2): 321-327, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32162163

RESUMO

The ultimate goal of organ regenerative therapy is to reproduce fully functional organs to replace which have been damaged as a result of diseases or injury. Although several studies claimed that using different types of cells in some animal models promote hair follicles regeneration, more researches can be done to develop a sufficient and efficient protocol to induce hair generation from different animal models. In this study, we investigated the therapeutic potentials for hair follicle formation by injecting a mixture of epidermal stem cells and dermal papilla cells. Those cells were isolated and culture-expanded. Then we randomly allocated 8 nude mice into two groups. The experiment group received an injection of a mixture that containing of epidermal stem cells and dermal papilla cells. The control group received injection of keratinocyte serum-free medium. The hair follicles regeneration was observed and the injection area was harvested for HE staining. 14 day later, the regenerated hair shafts were observed and HE staining indicated that the newly hair follicle formed the correct structures in experiment group. Furthermore, the mixture injection induced a regular and multilayered stratified epidermis and the epidermis contained of hair follicle-likes structures. Our data showed that injection of a mixture of epidermal stem cells and dermal papilla cells could induce hair follicles regeneration and well-ordered epidermis formation. This study emphasized that the rearrangement of the interactions during seed cells and the niches of the seed cells is essential and necessary for tissue-engineered construct success.


Assuntos
Derme/transplante , Células Epidérmicas/citologia , Folículo Piloso/fisiologia , Regeneração/fisiologia , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Bioengenharia , Masculino , Camundongos Nus , Ratos Sprague-Dawley
6.
Electromagn Biol Med ; 39(4): 251-256, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32727226

RESUMO

The bioeffects of low-frequency electromagnetic fields (EMF) on a bio-engineered hair follicle generation had not been fully elucidated. This present study was designed to evaluat the therapeutically effective of low frequency EMF on hair follicles regeneration. In this experiment, epidermal stem cells (ESCs) and dermal papilla (DP) cells were isolated and culture-expanded. Then the mixture containing of ESCs and DP cells was implanted into the epidermal layer or corium layer of nude mice. Those mice were  divided at random into the control group and EMF group, 7 days or 14 days later, the skin specimens were harvested to assess for hair regeneration or a bio-engineered skin formation using H&E staining. After injection of the mixture into the epidermal layer of nude mice for 14 days, H&E staining showed that the new hair formed the correct structure comprising hair matrix, hair shaft, and inner root sheath, outer root sheath, and DP. Comparing to the control, the hair follicles erupted at a higher density in the EMF group. When the mixture was implanted into the corium layer for 7 days, comparing with the characteristics of new hair follicles in the control group, H&E staining also showed the mixture induced to form 4 ~ 6 epidermal layers with a higher density of hair follicle like-structures in the bioengineered epithelial layers after EMF exposure. Our results suggested that the injection of a mixture of ESCs and DP cells in combination with EMF exposure facilitated the induction of hair follicle regeneration and a bioengineered skin formation with hair follicle-like structures.


Assuntos
Derme/citologia , Campos Eletromagnéticos , Folículo Piloso/fisiologia , Folículo Piloso/efeitos da radiação , Regeneração/efeitos da radiação , Células-Tronco/citologia , Animais , Bioengenharia , Folículo Piloso/citologia , Camundongos , Células-Tronco/efeitos da radiação
7.
Paediatr Anaesth ; 29(3): 243-249, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30664323

RESUMO

This Statistical Analysis Plan details the statistical procedures to be applied for the analysis of data for the multicenter electroencephalography study. It consists of a basic description of the study in broad terms and separate sections that detail the methods of different aspects of the statistical analysis, summarized under the following headings (a) Background; (b) Definitions of protocol violations; (c) Definitions of objectives and other terms; (d) Variables for analyses; (e) Handling of missing data and study bias; (f) Statistical analysis of the primary and secondary study outcomes; (g) Reporting of study results; and (h) References. It serves as a template for researchers interested in writing a Statistical Analysis Plan.


Assuntos
Interpretação Estatística de Dados , Eletroencefalografia/estatística & dados numéricos , Estatística como Assunto/normas , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Estudos Prospectivos
8.
Ecotoxicol Environ Saf ; 158: 100-107, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29665556

RESUMO

Wheat straw-supported Nanoscale Zero-Valent Iron particles (WS-NZVI) were successfully synthesized, which were used for Ciprofloxacin hydrochloride (CIP) removal in simulation wastewater. The structure, chemical composition and micro-morphology of WS-NZVI and Nanoscale Zero-Valent Iron (NZVI) were characterized by scanning electron microscopy analysis (SEM), X-ray diffraction (XRD), as well as the Fourier Transformed IR spectra (FT-IR). XRD results proved the existence of Fe°, and SEM images indicated that the agglomeration of NZVI was effectively inhibited when loaded on wheat straw. Besides, the effects of initial solution pH, CIP concentration, adsorbents dosage and contacting time on the removal efficiency of CIP by WS-NZVI and NZVI were investigated. The experimental results showed that, compared with NZVI and wheat straw, WS-NZVI possessed higher removal efficiency for CIP, and the maximum removal capacity of CIP by WS-NZVI was 363.63 mg g-1 (25 °C). Furthermore, WS-NZVI was suitable for wider pH range (pH = 4-10) in comparison with NZVI. For the WS-NZVI, the kinetic was better fitted with pseudo-second-order equation, rather than pseudo-first-order equation. The Mass spectrometry (MS) analysis deduced that the degradation reaction mainly occurred on quinolone groups piperazinyl ring. Therefore, it is feasible that using wheat straw as a support material to enhance the performance of NZVI, and the synthesized WS-NZVI has a potential in the organic compounds elimination because of its redox reaction activity.


Assuntos
Antibacterianos/análise , Ciprofloxacina/análise , Ferro/química , Poluentes Químicos da Água/análise , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Triticum , Águas Residuárias/análise , Difração de Raios X
9.
Biochem Biophys Res Commun ; 492(1): 140-146, 2017 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-28647372

RESUMO

BACKGROUND: Previous studies have described the protective effects of DADLE on myocardial injury in sepsis. Recently, autophagy has been shown to be an innate defense mechanism in sepsis-related myocardial injury. However, whether DADLE has an pro-autophagic effect is yet to be elucidated. The present study aimed to investigate the effect of DADLE on the regulation of autophagy during sepsis. METHODS: Male mice were subjected to LPS or vehicle intraperitoneal injection. After LPS injection, mice received either DADLE, Naltrindole or vehicle. ELISA and JC-1 were used to evaluate the level cTnI and Mitochondrial membrane potential. Cardiac ultrastructural and autophagosomes were visualized by transmission electron microscopy. The relative protein levels were analyzed by Western blot. RESULTS: The results showed that treatment with DADLE both immediately or 4 h after LPS intraperitoneal injection could improve the survival rate of mice with endotoxemic. DADLE could ease myocardium ultrastructure injury induced by LPS, this cardioprotective effect was also seen in increased MMP levels, and decreased cTnI levels. Through observation of transmission electron microscopy and Western blot we have discovered that the amount of autophagosome and the expression of autophagy related protein LC3II, Beclin1 were significantly increased with DADLE treatment. DADLE promoted LPS-induced autophagosome maturation as indicated by the increased LAMP-1 protein level and decreased SQSTM1/p62 protein level. The selective δ-opioid receptor antagonist Naltrindole play an opposite effects. CONCLUSIONS: DADLE could improve the survival and protect myocardial dysfunction in mice with LPS-induced endotoxemia. This effect was related to the increase of autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Leucina Encefalina-2-Alanina/farmacologia , Lipopolissacarídeos/farmacologia , Isquemia Miocárdica/tratamento farmacológico , Receptores Opioides delta/agonistas , Animais , Injeções Intraperitoneais , Lipopolissacarídeos/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Isquemia Miocárdica/metabolismo
10.
Biochem Biophys Res Commun ; 483(1): 318-324, 2017 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-28017719

RESUMO

Podocyte damage is the initial hallmark of diabetic nephropathy (DN), leading to the increasing morbidity and mortality in diabetic patients. Recent researches have corroborated the critical roles of miRNAs in the pathological progression of DN. Here, elevation of miR-217 was verified in high glucose (HG)-stimulated podocytes. Moreover, blocking miR-217 expression antagonized HG-induced cell injury by attenuating the adverse role of HG on cell viability and inhibiting ROS levels and cell apoptosis. Simultaneously, miR-217 repression restored HG-disrupted insulin resistance by elevating glucose uptake and nephrin expression, an essential component for insulin-induced glucose uptake. Mechanism assay substantiated the defective autophagy in HG-treated podocytes, which was resumed by miR-217 cessation. Importantly, suppressing autophagy pathway with 3-MA alleviated the protective roles of miR-217 down-regulation in podocyte injury and insulin resistance. Luciferase reporter analysis confirmed that PTEN was a target of miR-217 in podocytes. Additionally, blocking PTEN expression restrained autophagy restoration in miR-217-decreased cells. Furthermore, PTEN down-regulation attenuated the beneficial role of miR-217 suppression in HG-induced injury and insulin resistance. Together, this study manifests that miR-217inhibition can protectively antagonize HG-induced podocyte damage and insulin resistance by restoring the defective autophagy pathway via targeting PTEN, representing a novel and promising therapeutic target against diabetic nephropathy.


Assuntos
Autofagia , Regulação da Expressão Gênica , Glucose/metabolismo , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Podócitos/metabolismo , Animais , Apoptose , Sobrevivência Celular , Células Cultivadas , Nefropatias Diabéticas/metabolismo , Regulação para Baixo , Resistência à Insulina , Proteínas de Membrana/metabolismo , Camundongos , Oligonucleotídeos/química , Podócitos/citologia , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
Asian-Australas J Anim Sci ; 29(9): 1314-21, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26954131

RESUMO

We conducted this 10-wk experiment to evaluate the effects of dietary phytoncide, Korean pine extract as phytogenic feed additive (PFA), on growth performance, blood characteristics, and meat quality in finishing pigs. A total of 160 pigs ([Landrace×Yorkshire]×Duroc, body weight (BW) = 58.2±1.0 kg) were randomly allocated into 1 of 4 treatments according to their BW and sex, 10 replicate pens per treatment with 4 pigs per pen were used (2 barrows and 2 gilts). Dietary treatments were: CON, control diet; PT2, CON+0.02% PFA; PT4, CON+0.04% PFA; PT6, CON+0.06% PFA. Overall, average daily gain (ADG) was higher in PT4 (p<0.05) than in PT6, average daily feed intake (ADFI) was lower in PT6 than in CON (p<0.05). Besides ADFI decreased linearly (p<0.05) with the increased level of phytoncide and gain:feed ratio in PT4 treatment was higher (p<0.05) than CON treatment. During 5 to 10 weeks and overall, quadratic (p<0.05) effect was observed in ADG among the treatments. At the end of this experiment, pigs fed with PT4 diet had a greater (p<0.05) red blood cell concentration compared to the pigs fed CON diet. Water holding capacity increased linearly (p<0.05) with the increased level of phytoncide supplementation. Moreover, firmness, redness, yellowness, and drip loss at day 3 decreased linearly (p<0.05) with the increase in the level of phytoncide supplementation. In conclusion, inclusion of phytoncide could enhance growth performance without any adverse effects on meat quality in finishing pigs.

12.
J Environ Sci (China) ; 46: 55-62, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27521936

RESUMO

Octanoic acid (OA) was selected to represent fatty acids in effluent organic matter (EOM). The effects of feed solution (FS) properties, membrane orientation and initial permeate flux on OA fouling in forward osmosis (FO) were investigated. The undissociated OA formed a cake layer quickly and caused the water flux to decline significantly in the initial 0.5hr at unadjusted pH3.56; while the fully dissociated OA behaved as an anionic surfactant and promoted the water permeation at an elevated pH of 9.00. Moreover, except at the initial stage, the sudden decline of water flux (meaning the occurrence of severe membrane fouling) occurred in two conditions: 1. 0.5mmol/L Ca(2+), active layer facing draw solution (AL-DS) and 1.5mol/L NaCl (DS); 2. No Ca(2+), active layer-facing FS (AL-FS) and 4mol/L NaCl (DS). This demonstrated that cake layer compaction or pore blocking occurred only when enough foulants were absorbed into the membrane surface, and the water permeation was high enough to compact the deposit inside the porous substrate. Furthermore, bovine serum albumin (BSA) was selected as a co-foulant. The water flux of both co-foulants was between the fluxes obtained separately for the two foulants at pH3.56, and larger than the two values at pH9.00. This manifested that, at pH3.56, BSA alleviated the effect of the cake layer caused by OA, and OA enhanced BSA fouling simultaneously; while at pH9.00, the mutual effects of OA and BSA eased the membrane fouling.


Assuntos
Incrustação Biológica , Ácidos Graxos/análise , Membranas Artificiais , Poluentes da Água/análise , Purificação da Água/métodos , Cálcio , Floculação , Concentração de Íons de Hidrogênio , Osmose , Cloreto de Sódio
13.
J Environ Sci (China) ; 29: 124-30, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25766020

RESUMO

Precipitation of calcium carbonate (CaCO3) scale on heat transfer surfaces is a serious and expensive problem widely occurring in numerous industrial processes. In this study, we compared the scale inhibition effect of six kinds of commercial scale inhibitors and screened out the best one (scale inhibitor SQ-1211) to investigate its scale inhibition performance in highly saline conditions at high temperature through static scale inhibition tests. The influences of scale inhibitor dosage, temperature, heating time and pH on the inhibition efficiency of the optimal scale inhibitor were investigated. The morphologies and crystal structures of the precipitates were characterized by Scanning Electron Microscopy and X-ray Diffraction analysis. Results showed that the scale inhibition efficiency of the optimal scale inhibitor decreased with the increase of the reaction temperature. When the concentration of Ca2+ was 1600 mg/L, the scale inhibition rate could reach 90.7% at 80°C at pH8. The optimal scale inhibitor could effectively retard scaling at high temperature. In the presence of the optimal scale inhibitor, the main crystal structure of CaCO3 changed from calcite to aragonite.


Assuntos
Carbonato de Cálcio/química , Precipitação Química , Salinidade , Águas Residuárias/química , Cristalização , Temperatura Alta , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Eliminação de Resíduos Líquidos , Difração de Raios X
14.
BMC Psychiatry ; 14: 123, 2014 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-24767108

RESUMO

BACKGROUND: Amino acid neurotransmitters and nitric oxide (NO) are involved in the pathogenesis of major depressive disorder (MDD). Here we want to establish whether changes in their plasma levels may serve as biomarker for the melancholic subtype of this disorder. METHODS: Plasma levels of glutamic acid (Glu), aspartic acid (Asp), glycine (Gly), gamma-aminobutyric acid (GABA), and NO were determined in 27 medicine-naïve melancholic MDD patients and 30 matched controls. Seven of the MDD patients participated also in a follow-up study after 2 months' antidepressant treatment. The relationship between plasma and cerebral-spinal fluid (CSF) levels of these compounds was analyzed in an additional group of 10 non-depressed subjects. RESULTS: The plasma levels of Asp, Gly and GABA were significantly lower whereas the NO levels were significantly higher in melancholic MDD patients, also after 2 months of fluoxetine treatment. In the additional 10 non-depressed subjects, no significant correlation was observed between plasma and CSF levels of these compounds. CONCLUSION: These data give the first indication that decreased plasma levels of Asp, Gly and GABA and increased NO levels may serve as a clinical trait-marker for melancholic MDD. The specificity and selectivity of this putative trait-marker has to be investigated in follow-up studies.


Assuntos
Aminoácidos/sangue , Transtorno Depressivo Maior/sangue , Óxido Nítrico/sangue , Adulto , Idoso , Antidepressivos/uso terapêutico , Ácido Aspártico/sangue , Biomarcadores/sangue , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/tratamento farmacológico , Feminino , Seguimentos , Ácido Glutâmico/sangue , Glicina/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Ácido gama-Aminobutírico/sangue
15.
PLoS One ; 19(7): e0304516, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38950289

RESUMO

BACKGROUND: The connection between urinary bisphenol A (BPA) and hyperlipidemia is still unclear, and few studies have evaluated whether urinary BPA affects mortality among individuals with hyperlipidemia. Therefore, we aimed to investigate the link between urinary BPA and hyperlipidemia and assess the impact of urinary BPA on mortality risk in subjects with hyperlipidemia. METHODS: We analyzed data of the National Health and Nutrition Examination Survey from 2003 to 2016. Multivariable logistic analysis was performed to examine the relationship between urinary BPA and hyperlipidemia. Cox regression analysis was carried out to investigate the relationship between urinary BPA and all-cause mortality in subjects with hyperlipidemia. RESULTS: This study included 8,983 participants, of whom 6,317 (70.3%) were diagnosed with hyperlipidemia. The results showed that urinary BPA was higher in participants with hyperlipidemia group than those without hyperlipidemia (3.87 ± 0.32 vs. 2.98 ± 0.14, P = 0.01). Urinary BPA levels were analyzed in tertiles. Compared with tertile 1 of BPA (reference), the odds ratio (95% confidence interval) of hyperlipidemia related to tertile 3 of BPA was 1.28 (1.11-1.48). The hazard ratio for all-cause death associated with the highest versus lowest tertile of urinary BPA was 1.20 (95% confidence interval: 1.01-1.44; P = 0.04) among participants with hyperlipidemia. CONCLUSIONS: The study indicated a positive relationship between urinary BPA and the risk of hyperlipidemia. Urinary BPA was associated with a significantly higher risk of all-cause mortality in adults with hyperlipidemia.


Assuntos
Compostos Benzidrílicos , Hiperlipidemias , Inquéritos Nutricionais , Fenóis , Humanos , Fenóis/urina , Compostos Benzidrílicos/urina , Compostos Benzidrílicos/efeitos adversos , Hiperlipidemias/urina , Hiperlipidemias/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso
16.
Bioresour Technol ; 399: 130644, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552856

RESUMO

To address the low-carbon treatment requirements for municipal wastewater, a novel anaerobic acidification membrane bioreactor (AAMBR) was developed for recovering organic matter in terms of volatile fatty acids (VFAs). While the AAMBR successfully generated VFAs from municipal wastewater through forward osmosis (FO) membrane concentration, its operation was limited to a single pH value of 10.0. Here, performance of the AAMBR operating at acidic condition was evaluated and compared with that at alkaline condition. The findings revealed that the AAMBR with pH 5.0 efficiently transformed organic matter into acetic acid, propionic acid, and butyric acid, resulting in a VFAs yield of 0.48 g/g-CODfeed. In comparison with the AAMBR at pH 10.0, this study achieved a similar VFAs yield, a lower fouling tendency, a lower loss of nutrients and a lower controlling cost. In conclusion, this study demonstrated that a pH of 5.0 is optimal for the AAMBR treating municipal wastewater.


Assuntos
Reatores Biológicos , Águas Residuárias , Anaerobiose , Ácidos Graxos Voláteis , Concentração de Íons de Hidrogênio , Membranas Artificiais
17.
Water Res ; 254: 121378, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38430758

RESUMO

This study delved into the efficacy of sludge digestion and the mechanisms involved in sludge destruction during the implementation of forward osmosis process for sludge thickening and digestion (FO-MSTD). Utilizing a lab-scale FO membrane reactor for the thickening and digestion of waste activated sludge (WAS), the investigation explored the effects of sludge thickening and digestion in FO-MSTD processes using draw solutions of varying concentrations. The findings underscored the significance of hydraulic retention time (HRT) as a pivotal parameter influencing the swift thickening or profound digestion of sludge. Consequently, tailoring the HRT to specific processing objectives emerged as a key strategy for achieving desired treatment outcomes. In the investigation, the use of a 1 M NaCl draw solution in the FO-MSTD process showcased enhanced thickening and digestion capabilities. This specific setup raised the concentration of mixed liquor suspended solids (MLSS) to over 30 g/L and achieved a 42.7% digestion efficiency of mixed liquor volatile suspended solids (MLVSS) within an operational timeframe of 18 days. Furthermore, the research unveiled distinct stages in the sludge digestion process of the FO-MSTD system, characterized by fully aerobic digestion and aerobic-local anaerobic co-existing digestion. In the fully aerobic digestion stage, the sludge digestion rate exhibited a steady increase, leading to the breakdown of sludge floc structures and the release of a substantial amount of nutrients into the sludge supernatant. The predominant microorganisms during this stage were typical functional microorganisms found in wastewater treatment systems. Transitioning into the aerobic-local anaerobic co-existing digestion stage, both MLSS concentration and MLVSS digestion efficiency continued to rise, accompanied by a decreasing dissolved oxygen (DO) concentration. More organic matter was released into the supernatant, and sludge microbial flocs tended to reaggregate. The localized anaerobic environment within the FO-MSTD reactor fostered an increase in the relative abundance of bacteria with nitrogen and phosphorus removal functions, thereby positively impacting the mitigation of total nitrogen (TN) and total phosphorus (TP) concentrations in the sludge supernatant. The results of this research enhance comprehension of the advanced FO-MSTD technology in the treatment of WAS.


Assuntos
Fósforo , Esgotos , Esgotos/química , Osmose , Fósforo/metabolismo , Nitrogênio , Digestão , Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos
18.
Nanoscale ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990172

RESUMO

Functional mesoporous carbon nanomaterials with large pores and small particle sizes have broad accessibility, but remain challenging to achieve. This study proposed a dual-template synergistic assembly strategy to facilely synthesize extra-small nitrogen-doped mesoporous carbon nanospheres with large pores in a low-cost manner. Directed by the synergistic effect of the combination of surfactants, sodium oleate (anionic surfactant) and triblock copolymer-P123 (nonionic surfactant) were selected as templates to construct nanomicelles (nanoemulsions), which were co-assembled with melamine-based oligomers to form composite nanomicelles, thus obtaining nitrogen-doped mesoporous polymer nanospheres (NMePS) and then nitrogen-doped mesoporous carbon nanospheres (NMeCS). Based on Schiff base chemistry, the melamine-based oligomers with self-assembly capability were synthesized as precursors, which is different from the conventional synthetic route of melamine-formaldehyde resin. The key parameters involved in the route were investigated comprehensively and correlated with the characterization results. Furthermore, the 50 nm-scale particle size and the large mesoporous size of 5.5 nm of NMeCS can facilitate effective mass transport, coupled with their high nitrogen content (15.7 wt%), contributing to their excellent performance in lithium-ion batteries.

19.
ACS Appl Mater Interfaces ; 16(1): 1317-1325, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38118048

RESUMO

Piezoelectric nanogenerators (PENGs) with molybdenum disulfide (MoS2) monolayers have been intensively studied owing to their superior mechanical durability and stability. However, the limited output performance resulting from a small active area and low strain levels continues to pose a significant challenge that should be overcome. Herein, we report a novel strategy for the epoch-making output performance of a PENG with a MoS2 monolayer by adopting the additive strain concentration concept. The simulation study indicates that strain in the MoS2 monolayer can be initially augmented by the wavy structure resulting from the prestretched poly(dimethylsiloxane) (PDMS) and is further increased through flexural deformation (i.e., bending). Based on these studies, we have developed concentrated strain-applied PENGs with MoS2 monolayers. The wavy structures effectively applied strain to the MoS2 monolayer and generated a piezoelectric output voltage and current of around 580 mV and 47.5 nA, respectively. Our innovative approach to enhancing the performance of PENGs with MoS2 monolayers through the artificial dual strain concept has led to groundbreaking results, achieving the highest recorded output voltage and current for PENGs based on two-dimensional (2D) materials, which provides unique opportunities for the 2D-based energy harvesting field and structural insight into how to improve the net strain on 2D materials.

20.
Sci Adv ; 10(18): eadl5067, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701201

RESUMO

Airborne pathogens retain prolonged infectious activity once attached to the indoor environment, posing a pervasive threat to public health. Conventional air filters suffer from ineffective inactivation of the physics-separated microorganisms, and the chemical-based antimicrobial materials face challenges of poor stability/efficiency and inefficient viral inactivation. We, therefore, developed a rapid, reliable antimicrobial method against the attached indoor bacteria/viruses using a large-scale tunneling charge-motivated disinfection device fabricated by directly dispersing monolayer graphene on insulators. Free charges can be stably immobilized under the monolayer graphene through the tunneling effect. The stored charges can motivate continuous electron loss of attached microorganisms for accelerated disinfection, overcoming the diffusion limitation of chemical disinfectants. Complete (>99.99%) and broad-spectrum disinfection was achieved <1 min of attachment to the scaled-up device (25 square centimeters), reliably for 72 hours at high temperature (60°C) and humidity (90%). This method can be readily applied to high-touch surfaces in indoor environments for pathogen control.


Assuntos
Desinfecção , Eletrônica , Grafite , Desinfecção/métodos , Eletrônica/métodos , Grafite/química , Viabilidade Microbiana , Bactérias
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