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1.
Nature ; 630(8016): 346-352, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811731

RESUMO

Vertical three-dimensional integration of two-dimensional (2D) semiconductors holds great promise, as it offers the possibility to scale up logic layers in the z axis1-3. Indeed, vertical complementary field-effect transistors (CFETs) built with such mixed-dimensional heterostructures4,5, as well as hetero-2D layers with different carrier types6-8, have been demonstrated recently. However, so far, the lack of a controllable doping scheme (especially p-doped WSe2 (refs. 9-17) and MoS2 (refs. 11,18-28)) in 2D semiconductors, preferably in a stable and non-destructive manner, has greatly impeded the bottom-up scaling of complementary logic circuitries. Here we show that, by bringing transition metal dichalcogenides, such as MoS2, atop a van der Waals (vdW) antiferromagnetic insulator chromium oxychloride (CrOCl), the carrier polarity in MoS2 can be readily reconfigured from n- to p-type via strong vdW interfacial coupling. The consequential band alignment yields transistors with room-temperature hole mobilities up to approximately 425 cm2 V-1 s-1, on/off ratios reaching 106 and air-stable performance for over one year. Based on this approach, vertically constructed complementary logic, including inverters with 6 vdW layers, NANDs with 14 vdW layers and SRAMs with 14 vdW layers, are further demonstrated. Our findings of polarity-engineered p- and n-type 2D semiconductor channels with and without vdW intercalation are robust and universal to various materials and thus may throw light on future three-dimensional vertically integrated circuits based on 2D logic gates.

2.
Nanotechnology ; 34(47)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37591213

RESUMO

In this research work, a reusable and efficient 2D/1D heterogeneous structured photocatalyst based on amine-functionalized halloysite nanotubes (MHNTs) and Bi2WO6nanosheet (BWO) was prepared using a facile hydrothermal method for decomposing PPCPs under simulated sunlight. On the degradation of tetracycline hydrochloride (TCH), the effects of composite catalysts prepared under various conditions were discussed. The results showed that over BWO/MHNTs with a mass ratio was 3:1, the synthesizing temperature was 120 °C and the precursor pH value was 1, the TCH (10 mg l-1) degradation efficiency reached 100% after 1 h irradiation of simulated sunlight. Moreover, BWO/MHNTs composites kept good recovery and stable photocatalytic activity after 5 cycles. The excellent dispersion of Bi2WO6on the surface of clay minerals and the oxygen vacancy enhanced electron-hole separation may be responsible for the its high activity and stability. Futhermore, the radical capture test demonstrated that ·O-2was primarily responsible for the photodegradation of TCH. Thus, BWO/MHNTs composites exhibit a good application prospect in the field of sunlight-driven photocatalytic degradation towards PPCPs pollutants in water.

3.
Molecules ; 28(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38005302

RESUMO

The high specific capacity of transition metal sulfides (TMSs) opens up a promising new development direction for lithium-ion batteries with high energy storage. However, the poor conductivity and serious volume expansion during charge and discharge hinder their further development. In this work, trimetallic sulfide Zn-Co-Fe-S@nitrogen-doped carbon (Zn-Co-Fe-S@N-C) polyhedron composite with a core-shell structure is synthesized through a simple self-template method using ZnCoFe-ZIF as precursor, followed by a dopamine surface polymerization process and sulfidation during high-temperature calcination. The obvious space between the internal core and the external shell of the Zn-Co-Fe-S@N-C composites can effectively alleviate the volume expansion and shorten the diffusion path of Li ions during charge and discharge cycles. The nitrogen-doped carbon shell not only significantly improves the electrical conductivity of the material, but also strengthens the structural stability of the material. The synergistic effect between polymetallic sulfides improves the electrochemical reactivity. When used as an anode in lithium-ion batteries (LIBs), the prepared Zn-Co-Fe-S@N-C composite exhibits a high specific capacity retention (966.6 mA h g-1 after 100 cycles at current rate of 100 mA g-1) and good cyclic stability (499.17 mA h g-1 after 120 cycles at current rate of 2000 mA g-1).

4.
Molecules ; 28(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37049952

RESUMO

Non-alcoholic steatohepatitis (NASH) is a metabolic disorder that often leads to other severe liver diseases, yet treatment options are limited. Endoplasmic reticulum (ER) stress is an important pathogenetic mechanism of NASH and plays a key role in tandem steatosis as well as liver inflammation. This study aims to develop a progressive NASH model through sustained lipid accumulation and to elucidate its molecular mechanism through IRE1α/TRAF2 complex. Male SD rats were fed a high-fat diet (HFD) for 4, 8, and 12 weeks to induce progressive NASH. MRNA sequencing and PPI analysis were used to screen core genes. Transmission electron microscopy, immunofluorescence staining, ELISA, qRT-PCR, and Western blotting were used at each time point to compare differences between each index of progressive NASH at 4, 8, and 12 weeks. Sustained lipid accumulation led to structural disruption of the ER, a reduction in ER number, and an increase of lipid droplet aggregation in hepatocytes. Persistent lipid accumulation led to a persistent increase in mRNA and protein expression of the IRE1α/TRAF2 complex, IKK/IκB/NF-κB signaling pathway and ASK1/JNK1 signaling pathway, and TNF-α, IL-1ß, and IL-6 also continued to increase. Persistent lipid accumulation led to a persistent exacerbation of ER stress and inflammation in progressive NASH via the IRE1α/TRAF2 complex.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fator 2 Associado a Receptor de TNF/genética , Fator 2 Associado a Receptor de TNF/metabolismo , Endorribonucleases/genética , Endorribonucleases/metabolismo , Ratos Sprague-Dawley , Inflamação/metabolismo , Estresse do Retículo Endoplasmático , Lipídeos , Fígado/metabolismo
5.
Emerg Infect Dis ; 28(12): 2389-2397, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36417925

RESUMO

Since its initial identification in 1986, Lyme disease has been clinically diagnosed in 29 provinces in China; however, national incidence data are lacking. To summarize Lyme disease seropositivity data among persons across China, we conducted a systematic literature review of Chinese- and English-language journal articles published during 2005‒2020. According to 72 estimates that measured IgG by using a diagnostic enzyme-linked assay (EIA) alone, the seropositivity point prevalence with a fixed-effects model was 9.1%. A more conservative 2-tier testing approach of EIA plus a confirmatory Western immunoblot (16 estimates) yielded seropositivity 1.8%. Seropositivity by EIA for high-risk exposure populations was 10.0% and for low-risk exposure populations was 4.5%; seropositivity was highest in the northeastern and western provinces. Our analysis confirms Lyme disease prevalence, measured by seropositivity, in many Chinese provinces and populations at risk. This information can be used to focus prevention measures in provinces where seropositivity is high.


Assuntos
Borrelia burgdorferi , Doença de Lyme , Humanos , Doença de Lyme/diagnóstico , Doença de Lyme/epidemiologia , Western Blotting , Prevalência , China/epidemiologia
6.
Phys Chem Chem Phys ; 24(32): 19362-19370, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35919974

RESUMO

Sodium ion technology is increasingly investigated as a low-cost solution for grid storage applications. Among the reported cathode materials for sodium-ion batteries, Na3V2(PO4)2FO2 is considered as one of the most promising materials due to its high operation voltage and good cyclability. Here, the de-sodiumization process of Na3V2(PO4)2FO2 has been systematically examined using first-principles calculations to uncover the fundamental questions at the atomic level. Four stable intermediate products during the de-sodiumization process are firstly determined based on the convex hull, and three voltage platforms are then predicted. Except for two voltage platforms (3.37 V and 3.75 V) close to the experimental values, the platform up to 5.28 V exceeds the stability window (4.8 V) of a typical electrolyte, which was not observed experimentally. Excitingly, the change of volume is only 2% during the sodiumization process, which should be the reason for the good cycling stability of this material. Electronic structure analysis also reveals that the valence states of V ions will be changed from V5+ to V4+ during the sodiumization process, resulting in a weak Jahn-Teller distortion in VO5F octahedra, and then making the lattice-constants asymmetrically change. More seriously, combined with a bandgap of 2.0 eV, the conduction band minimum mainly composed of V-t2g non-bonding orbitals has strong localized characteristics, which should be the intrinsic origin of poor electron transport properties for NaxV2(PO4)2FO2. Nonetheless, benefiting from the layer-like structure features with F-segmentation, this material has an ultrafast sodium ionic conductivity comparable to that of NASICON, with an activation energy of only 82 meV. Therefore, our results indicate that maintaining layer-like features and regulating V atoms will be important directions to improve the performance of NaxV2(PO4)2FO2.

7.
Sensors (Basel) ; 22(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36236283

RESUMO

Electrical impedance tomography (EIT) has been applied in the field of human-computer interaction due to its advantages including the fact that it is non-invasive and has both low power consumption and a low cost. Previous work has focused on static gesture recognition based on EIT. Compared with static gestures, dynamic gestures are more informative and can achieve more functions in human-machine collaboration. In order to verify the feasibility of dynamic gesture recognition based on EIT, a traditional excitation drive pattern is optimized in this paper. The drive pattern of the fixed excitation electrode is tested for the first time to simplify the measurement process of the dynamic gesture. To improve the recognition accuracy of the dynamic gestures, a dual-channel feature extraction network combining a convolutional neural network (CNN) and gated recurrent unit (GRU), namely CG-SVM, is proposed. The new center distance loss is designed in order to simultaneously supervise the intra-class distance and inter-class distance. As a result, the discriminability of the confusing data is improved. With the new excitation drive pattern and classification network, the recognition accuracy of different interference data has increased by 2.7~14.2%. The new method has stronger robustness, and realizes the dynamic gesture recognition based on EIT for the first time.


Assuntos
Gestos , Reconhecimento Automatizado de Padrão , Algoritmos , Impedância Elétrica , Mãos/diagnóstico por imagem , Humanos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Tomografia
8.
Phys Rev Lett ; 127(13): 136101, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34623842

RESUMO

A prototype Schwarz crystal (SC) structure of dividing-space minimal grain boundaries (GBs) constrained by coherent twin boundaries (CTBs) was recently discovered in extremely fine-grained polycrystalline Cu. In this Letter, constraining effects of 3D CTB network on the formation and thermostability of SC are addressed via atomistic simulations. GB migration and evolution of CTB network trigger formation of SC diamond. CTB constraints are critical to generate GBs of zero mean curvature underlying vanishing capillary pressure, and to counterbalance the elastic driving forces of lattice. GB motion can be suppressed at temperatures close to the melting point with GB aperture down to 3 nm.

9.
Nanotechnology ; 32(31)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33862612

RESUMO

As researchers are striving to develop high-performance filtration membranes with hierarchical micro/nano structures, the challenges and costs of processing often limit creative innovation. Here, we propose a polyethersulfone/polyacrylonitrile (PES/PAN) nanofiber membrane with groove structure by electrospinning and facile post-processing. The resulted membrane can form a groove structure on the surface of the fiber after being soaked in chloroform, thereby increasing the collision probability and extending the residence time for ultrafine particulates and improving the filtration efficiency. The groove structure can be attributed to the solubility of PES constituent in chloroform, while PAN constituent will not be dissolved, thus forming a high-performance nanofiber membrane with high filtration efficiency (ca. 99.54%) and withstand pressure drop (ca. 133.9 Pa) for dioctyl phthalate aerosol particles with diameter of 0.3µm. The results show that this convenient and low-cost fabrication technology can be used to prepare high-performance nanofiber membrane based air filters that have broad application prospects in respiratory protective equipment.

10.
Environ Res ; 197: 111089, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33811867

RESUMO

The completely biological degradation of Tetrabromobisphenol A (TBBPA) contaminant is challenging. Bio-electrochemical systems are efficient to promote electrons transfer between microbes and pollutants to improve the degradation of refractory contaminants. In particular, three-dimensional biofilm electrode reactors (3DBERs), integrating the biofilm with particle electrodes, represent a novel bio-electrochemical technology with superior treatment performances. In this study, the electroactive biofilm is cultured and acclimated on two types of particle electrodes, granular activated carbon (GAC) and granular zeolite (GZ), to degrade the target pollutant TBBPA in 3DBERs. Compared to GZ, GAC materials are more favorable for biofilm formation in terms of high specific surface area and good conductivity. The genus of Thauera is efficiently enriched on both GAC and GZ particles, whose growth is promoted by the electricity. By applying 5 V voltage, TBBPA can be removed by over 95% in 120 min whether packing GAC or GZ particle electrodes in 3DBERs. The synergy of electricity and biofilm in TBBPA degradation was more significant in GAC packed 3DBER, because the improved microbial activity by electrical stimulation accelerates debromination rate and hence the decomposition of TBBPA. Applying electricity also promotes TBBPA degradation in GZ packed 3DBER mainly due to the enhanced electrochemical effects. Roles of particle electrode materials in TBBPA removal are distinguished in this work, bringing new insights into refractory wastewater treatment by 3DBERs.


Assuntos
Reatores Biológicos , Bifenil Polibromatos , Biofilmes , Eletrodos
11.
Phys Chem Chem Phys ; 22(39): 22236-22243, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33000818

RESUMO

The lack of high-performance anode materials has become a major obstacle to the development of Li- and Na-ion batteries. Recently, 2D transition metal borides (e.g. MBenes) have attracted much attention due to their excellent stability and electrical conductivity. Unfortunately, most of the reported MBene phases typically have an intrinsic metal-rich structure with metal atoms exposed on the surface, which harmfully affect the adsorption of Li/Na atoms. Here, through crystal structure prediction combined with the first-principles density functional theory, a novel TiB3 MBene has been determined by altering the proportion of non-metallic element boron to wrap metal atoms and weaken nearest-neighbor electrostatic repulsion. Electrostatic potential analysis visually shows a surface with low potential on the TiB3 monolayer implying high adsorption capacity, and also can be used to quickly screen out the Li/Na adsorption sites. Accurate half-cell battery simulation confirmably shows that the TiB3 monolayer possesses a theoretical specific capacity of 1335.04 and 667.52 mA h g-1 for Li and Na, respectively. The TiB3 monolayer can remain metallic after adsorbing Li/Na atoms, which ensures good conductivity during battery cycling. The ultra-low barrier energy (only 38 meV for Li) and suitable open-circuit voltage indicate excellent charging and discharging capabilities. These results suggest that the TiB3 monolayer could be a promising anode material for Li- and Na-ion batteries, and provide a simple design principle for exposing non-metallic atoms on the surface.

12.
Sensors (Basel) ; 20(9)2020 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-32357444

RESUMO

Pressure sensors have been widely used in electronic wearable devices and medical devices to detect tiny physical movements and mechanical deformation. However, it remains a challenge to fabricate desirable, comfortable wearing, and highly sensitive as well as fast responsive sensors to capture human body physiological signs. Here, a new capacitive flexible pressure sensor that is likely to solve this problem was constructed using thermoplastic polyurethane elastomer rubber (TPU) electrospinning nanofiber membranes as a stretchable substrate with the incorporation of silver nanowires (AgNWs) to build a composite dielectric layer. In addition, carbon nanotubes (CNTs) were painted on the TPU membranes as flexible electrodes by screen printing to maintain the flexibility and breathability of the sensors. The flexible pressure sensor could detect tiny body signs; fairly small physical presses and mechanical deformation based on the variation in capacitance due to the synergistic effects of microstructure and easily altered composite permittivity of AgNW/TPU composite dielectric layers. The resultant sensors exhibited high sensitivity (7.24 kPa-1 within the range of 9.0 × 10-3 ~ 0.98 kPa), low detection limit (9.24 Pa), and remarkable breathability as well as fast responsiveness (<55 ms). Moreover, both continuously pressing/releasing cycle over 1000 s and bending over 1000 times did not impair the sensitivity, stability, and durability of this flexible pressure sensor. This proposed strategy combining the elastomer nanofiber membrane and AgNW dopant demonstrates a cost-effective and scalable fabrication of capacitive pressure sensors as a promising application in electronic skins and wearable devices.


Assuntos
Técnicas Biossensoriais , Membranas Artificiais , Dispositivos Eletrônicos Vestíveis , Elastômeros , Capacitância Elétrica , Humanos , Membranas , Nanofibras , Nanotubos de Carbono , Nanofios , Poliuretanos , Pressão
13.
J Environ Manage ; 258: 110021, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929062

RESUMO

Coking wastewater is highly concentrated and extremely toxic, greatly challenging the treatment technologies. Conventional biological technology such as anaerobic-anoxic-oxic (A2O) system is inefficient, since various biological reactions are inhibited by toxicants in coking wastewater. In this work, a pilot-scale three-dimensional electrochemical reactor (3DER) is integrated into the A2O system as a pretreatment unit to improve the treatment efficiency of coking wastewater. The results indicate that 3DER pretreatment increased the biodegradability of coking wastewater, promoting the degradation of coking wastewater in A2O system. The integrated 3DER-A2O system can remove 94.4% of COD and 76.2% of TN from coking wastewater, and the energy consumption was only 0.22 kWh/kg COD and 4.69 kWh/kg TN. The components of coking wastewater were significantly simplified and the acute toxicity was reduced from 99% to 12% after the treatment. The integrated 3DER-A2O system provides a new solution for coking wastewater treatment, showing a promising application potential.


Assuntos
Coque , Águas Residuárias , Anaerobiose , Reatores Biológicos , Eliminação de Resíduos Líquidos
14.
Opt Lett ; 44(21): 5322-5325, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674998

RESUMO

In this Letter, a novel humidity sensor based on a chip-scale silicon nanobeam cavity with polymethyl methacrylate (PMMA) cladding is demonstrated. This sensor is easy to fabricate and compatible with CMOS technology. It shows a humidity sensing with a linear wavelength dependence of 22.9 pm/% relative humidity (RH) in a wide range of RH from 10% to 85%, an ultra-fast response time of 540 ms, and high stability. After annealing, the sensor exhibits high reversibility, repeatability, and temperature insensitivity at the range of 25°C-40°C. To the best of our knowledge, this is the first application of integrated photonics in high performance humidity detection. It provides a new way for the chip-scale sensor to integrate with photonic devices and optical systems.

15.
Phys Rev Lett ; 122(12): 126101, 2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30978032

RESUMO

The greatly increased grain boundary (GB) mobility in nanograined metals under mechanical loading is distinguished from that in their coarse-grained counterparts. The feature leads to softening of nanograined materials and deviation of strength from the classical Hall-Petch relationship. In this Letter, grain size dependences of GB migration in nanograined Ag, Cu, and Ni under tension were investigated quantitatively in a wide size range. As grain size decreases from submicron, GB migration intensifies and then diminishes below a critical grain size. The GB migration peaks at about 80, 75, and 38 nm in Ag, Cu, and Ni, respectively. The suppression of GB migration below a critical size can be attributed to GB relaxation during sample processing or by postthermal annealing. With relaxed GBs the governing deformation mechanism of nanograins shifts from GB migration to formation of through-grain twins or stacking faults. GB relaxation, analogous to GB segregation, offers a novel approach to stabilizing nanograined materials under mechanical loading.

16.
Phys Chem Chem Phys ; 21(34): 18559-18568, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31411206

RESUMO

The development of lithium-sulfur (Li-S) batteries is hindered by capacity loss due to lithium polysulfide (LIPS) dissolution into electrolyte solutions (known as the "shuttle effect"). MXenes with excellent electrical conductivity, high mechanical strength and multiple possible active two-dimensional surface terminations are attracting much attention as anchoring materials of Li-S batteries. Here, the S-functionalized V2C (V2CS2) is designed and demonstrated to have not only dynamic and thermal stability, but also metallic character. Compared with bare V2C and V2CO2, V2CS2 exhibits a moderate adsorption effect to suppress the "shuttle effect" and can preserve the structure of LIPSs without any decomposition. Moreover, the metallic properties of V2CS2 are maintained after LIPSs are adsorbed, which can promote the electrochemical activity during the charge and discharge process. The low energy barriers of Li2S decomposition and Li diffusion on the V2CS2 surface promise the phase transformation of LIPSs and assist the electrochemical process. Based on these remarkable results, we can conclude that V2CS2 is a promising anchoring material for lithium-sulfur batteries. Our work may also inspire the exploration of other MXenes and new surface functionalization methods to improve the performance of MXenes as host materials for high performance Li-S batteries.

17.
Chem Pharm Bull (Tokyo) ; 67(5): 419-425, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061366

RESUMO

Patients with type 2 diabetes (T2DM) and hyperlipidemia are with high risk of myocardial infarction (MI) or coronary death events. The combined use of ezetimibe and atorvastatin could improve treatment efficacy and safety. To explore the efficacy and safety of ezetimibe in combination with atorvastatin for the treatment of patients with T2DM and acute coronary syndrome (ACS). This was a non-randomized cohort study of 95 consecutive, treatment-naïve patients with T2DM and ACS treated at the Quanzhou First Hospital of Fujian Province between February 2014 and March 2016. According to the treatment strategy they selected, the patients were categorized into the atorvastatin (n = 46) and atorvastatin + ezetimibe (n = 49) groups. The patients were followed up at 2 weeks and 12 months. The primary endpoints included the incidence of adverse cardiovascular events and changed in blood lipids and high-sensitivity C-reactive protein (hs-CRP). At 12 months, serum total cholesterol (TC), triglycerides, and low-density lipoprotein cholesterol (LDL-C) levels were significantly lower, and high-density lipoprotein cholesterol (HDL-C) levels were significantly higher in the atorvastatin + ezetimibe (EZ) group than in the atorvastatin group (all p < 0.05). The LDL-C control rate at 12 months was significantly higher in the atorvastatin + EZ group compared with the atorvastatin group (p = 0.006). Seven patients in the atorvastatin group were re-hospitalized for angina pectoris, while only one patient in the atorvastatin + EZ group was re-hospitalized for angina pectoris (p = 0.02). The efficacy of atorvastatin + EZ in treating T2DM patients accompanied with ACS was significantly higher than using atorvastatin alone. This combined strategy has good safety profile, and could be recommended for clinical application.


Assuntos
Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/tratamento farmacológico , Anticolesterolemiantes/uso terapêutico , Atorvastatina/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Ezetimiba/uso terapêutico , Síndrome Coronariana Aguda/sangue , Anticolesterolemiantes/efeitos adversos , Atorvastatina/efeitos adversos , Proteína C-Reativa/análise , Estudos de Coortes , Diabetes Mellitus Tipo 2/sangue , Quimioterapia Combinada , Ezetimiba/efeitos adversos , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Miocárdio/enzimologia
18.
J Environ Manage ; 232: 219-225, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30476683

RESUMO

Triclosan (TCS) contaminant has aroused wide concerns due to the high risk of converting into toxic dioxin in aquatic environments. During the wastewater treatment process, considerable amounts of TCS are accumulated in activated sludge but the mechanisms are still unclear. Especially, roles of extracellular polymeric substances (EPS), the main components of activated sludge, in TCS removal have never been addressed. In this work, the binding properties of loosely-bound EPS (LB-EPS) and tightly-bound EPS (TB-EPS) of activated sludge to TCS are investigated by fluorescence quenching approach. The influences of aquatic conditions including solution pH, ionic strength and temperature on the interactions between EPS and TCS are explored. Possible interaction mechanisms are discussed as well as the corresponding environmental implication. Results indicate that binding processes of EPS to TCS are exothermic mainly driven by the enthalpy changes. The proteins components in EPS dominate the interactions between EPS and TCS by hydrogen bond and hydrophobic interaction. The binding strength could be improved under the condition of weak alkaline and relative high ionic strength. Generally, LB-EPS exhibit stronger binding ability to TCS than TB-EPS under neutral environment, playing more crucial roles in the binding process. This work highlights the important contributions of EPS to TCS removal, that is beneficial to comprehensively understand the migration of TCS in activated sludge system.


Assuntos
Esgotos , Triclosan , Matriz Extracelular de Substâncias Poliméricas , Termodinâmica , Águas Residuárias
19.
Sheng Li Xue Bao ; 71(6): 855-862, 2019 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-31879741

RESUMO

To study the effects of the anthocyanin single component cyanidin-3-O-glucoside (Cy-3-glu) on the proliferation and migration of mouse melanoma cells and to elucidate the underlying mechanisms, B16-F10 cells were treated with different concentrations of Cy-3-glu. Cell viability was analyzed by a CCK-8 method. Cell migration was determined by the callus scratching technique. Cell cycle was measured by the flow cytometry. The expression levels of genes involved in cell cycle regulation were detected by real-time PCR. Protein expression levels of p-AKT, E-cadherin, N-cadherin and vimentin were analyzed by Western blot. The growth and migration of B16-F10 cells in C57BL/6J mice were monitored by the cryogenically cooled IVIS-imaging system. The results showed that Cy-3-glu significantly inhibited the growth (P < 0.001) and migration (P < 0.01) of B16-F10 cells, and arrested the cell cycle in the S phase. After Cy-3-glu treatment, the expression levels of p-AKT (P < 0.05), N-cadherin and vimentin (P < 0.001) were decreased significantly, and the expression level of E-cadherin was dramatically increased (P < 0.05). The size and weight of tumors and tumor metastasis in mice fed with a diet containing Cy-3-glu were significantly reduced (P < 0.05). In conclusion, Cy-3-glu inhibits proliferation and migration of B16-F10 cells by inhibiting the PI3K/AKT signaling pathway, cell adhesion and migration signals.


Assuntos
Antocianinas , Glucosídeos , Animais , Antocianinas/química , Antocianinas/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glucosídeos/farmacologia , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/metabolismo
20.
J Environ Manage ; 218: 300-308, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29689533

RESUMO

The removal of high-concentration rhodamine B (RhB) wastewater was investigated in a three-dimensional electrochemical reactor (3DER) packed with granular activated carbon (GAC) particle electrodes. Response surface methodology (RSM) coupled with grey relational analysis (GRA) was used to evaluate the effects of voltage, initial pH, aeration rate and NaCl dosage on RhB removal and energy consumption of the 3DER. The optimal conditions were determined as voltage 7.25 V, pH 5.99, aeration rate 151.13 mL/min, and NaCl concentration 0.11 mol/L. After 30 min electrolysis, COD removal rate could arrive at 60.13% with an extremely low energy consumption of 6.22 kWh/kg COD. The voltage and NaCl were demonstrated to be the most significant factors affecting the COD removal and energy consumption of 3DER. The intermediates generated during the treatment process were identified and the possible degradation pathway of RhB was proposed. It is worth noting that 3DER also showed an excellent performance in total nitrogen (TN) removal under the optimal condition. The activated chlorine generated from chloride had great contributions to eliminate carbon and nitrogen of RhB wastewater. The treatment effluent had a good biodegradability, which was suitable for subsequent biological treatment.


Assuntos
Rodaminas/isolamento & purificação , Águas Residuárias , Purificação da Água , Carvão Vegetal , Eletroquímica , Eletrólise , Eliminação de Resíduos Líquidos
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