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BACKGROUND: To evaluate the clinical efficacy of supra-hemodiafiltration with endogenous reinfusion (Supra-HFR) for pruritus in uremic maintenance hemodialysis (HD) patients and explore the possible mechanism. METHODS: This study prospectively included 60 patients with uremia who underwent maintenance hemodialysis and developed pruritus. Patients were randomly divided into a study group (30 cases) and a control group (30 cases). Patients in the study group underwent dialysis once a week with Supra-HFR and twice a week with HD. The group received HD dialysis 3 times a week. Visual analog scales (VAS) scores, 5-D itch scale scores, and 12-Item Pruritus Severity Scale (12-PSS) were used to evaluate the itching degree of patients. Quality of life was assessed using KDTA and SF-36 scores. Blood levels of hypersensitive C-reactive protein, calcium ion (Ca2+), phosphorus ion (P3+ ), free parathyroid hormone (iPTH), and ß2-microglobulin (ß2-MG) were compared between the two groups before treatment and at follow-up 24 weeks after treatment. RESULTS: Before treatment, there was no significant difference in VAS, 5-D itch scale, and 12-PSS score between the study group and the control group (all p > 0.05). After 24 weeks of treatment, the VAS score of the study group (2.82 ± 0.91) was significantly lower than that of the control group (7.47 ± 1.32, p < 0.001), the 5-D itch scale score of the study group (9.47 ± 2.34) was significantly lower than that of the control group (18.53 ± 4.02, p < 0.001), the 12-PSS score of the study group (11.20 ± 1.81) was significantly lower than that of the control group (16.47 ± 2.09, p < 0.001). KDTA of the study group (64.17 ± 8.07 vs. 47.83 ± 13.46, p < 0.001) and SF-36 scores (65.37 ± 6.28 vs. 55.90 ± 14.28, p = 0.002) were significantly higher than that in the control group. The levels of hs-CRP, P3+ , iPTH, and ß2-MG in the study group after treatment were lower than those before treatment, and lower than those in the control group after treatment (all p < 0.05). CONCLUSIONS: The Supra-HFR can effectively reduce the itching symptoms of uremia patients and improve their quality of life.
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Hemodiafiltração , Insuficiência Renal , Uremia , Humanos , Qualidade de Vida , Diálise Renal/efeitos adversos , Uremia/complicações , Uremia/terapia , Proteína C-Reativa , Prurido/etiologia , Prurido/terapiaRESUMO
Vibrio parahaemolyticus, a sea-born bacterial pathogen, is a primary inducement of food-borne gastroenteritis. Previous studies have shown that non-coding small RNA plays a vital role in the regulation of multiple biological processes in pathogenic bacteria, especially autoaggregation and growth competition. However, the inherent mechanisms have not yet to be fully understood. As important regulators in Vibrios, the involvement of Qrr sRNAs in V. parahaemolyticus is largely unknown. Here, we carried out the Qrr5 deletion mutant and utilized a proteomic method to describe global proteomic alterations in response to Qrr5 deletion. A total of 297 significantly expressed proteins were determined between the Qrr5 deletion mutant and wild-type strain, among which 137 proteins were upregulated and 160 proteins were downregulated. The upregulated proteins principally participated in membrane transporters and signal transcription, while the downregulated proteins participated in the two-component system and transcription factor binding. Notably, transcriptional regulator LysR, outer membrane protein OmpA, and conjugal transfer protein TraA-related proteins were upregulated, causing the promotion of autoaggregation ability and growth competition ability against E. coli. This study provides insights into the regulatory network of sRNA in this bacterium, which will facilitate further explorations of important biological processes in pathogenic bacteria. SIGNIFICANCE: sRNA Qrr5 is an important regulator involved in bacterial multiple physiological processes, including auto-aggregation and growth competition among food-borne pathogens Vibrio parahaemolyticus. Here, utilizing a TMT-labeling proteomic approach, we identified 137 proteins were upregulated and 160 proteins were downregulated between the Qrr5 deletion mutant and wild-type strain. The upregulated proteins were involved in membrane transporters and signal transcription, while downregulated proteins were involved in the two-component system and transcription factor binding. Moreover, the LysR, OmpA, and TraA proteins were significantly upregulated, causing the promotion of autoaggregation and commensal growth competition ability. The mechanism of how Qrr5 regulates the targeted genes remains unclarified and need great efforts to explore.
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Fenômenos Biológicos , Pequeno RNA não Traduzido , Vibrio parahaemolyticus , Proteômica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/metabolismo , Escherichia coli/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Pequeno RNA não Traduzido/metabolismoRESUMO
OBJECTIVE: To observe the effect of ticagrelor on the function of a tunneled cuffed catheter (TCC) in maintenance hemodialysis (MHD) patients. METHODS: Eighty MHD patients (control group: 39 cases, observation group: 41 cases) using TCC as vascular access were enrolled from January 2019 to October 2020 in this prospective study. Patients in the control group were routinely treated with aspirin for antiplatelet therapy, while patients in the observation group were treated with ticagrelor. The catheter life time, catheter dysfunction, coagulation function, and antiplatelet drug-related adverse events of the two groups were recorded. RESULTS: The median life time of TCC in the control group was significantly higher than that in the observation group. Moreover, the log rank test showed that the difference was statistically significant (p < 0.001). CONCLUSION: Ticagrelor may reduce the incidence of catheter dysfunction and prolong the life time of the catheter by preventing and reducing the thrombosis of TCC in MHD patients, without obvious side effects.
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Cateterismo Venoso Central , Humanos , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Ticagrelor , Estudos Prospectivos , Diálise Renal/efeitos adversosRESUMO
Vibrio parahaemolyticus outbreaks frequently occur, causing gastrointestinal sickness owing to the consumption of aquatic foods by various virulence factors; however, the mechanism of pathogenesis is still unknown. In this study, a non-typical strain of V. parahaemolyticus, named VP353, was isolated from shrimp in China. Its comparative genome and transcriptome after infection with Caco-2 cells were examined to illustrate the mechanisms of its pathogenesis. VP353 was a tdh-trh- strain but uncommonly manifested robust cytotoxicity towards Caco-2 cells. Compared with the standard strain RIMD2210633, VP353 harbored alpha-hemolysins (hlyA, hlyB, hlyC, and hlyD) was first reported in V. parahaemolyticus and showed high diversity in the T3SS2 gene cluster. Moreover, the expression of flagella, T2SS, quorum sensing-related genes, hlyA, hlyC were up-regulated, and hlyB, hlyD were down-regulated. In summary, our results demonstrate that some novel virulence factors contribute to the pathogenesis of V. parahaemolyticus infection.
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Vibrioses , Vibrio parahaemolyticus , Humanos , Células CACO-2 , Perfilação da Expressão Gênica , Proteínas Hemolisinas/genética , Alimentos Marinhos/análise , Fatores de Virulência/genéticaRESUMO
Small non-coding RNAs (sRNAs) in bacteria are important regulatory molecules for controlling virulence. In Vibrio spp., Qrr sRNAs are critical for quorum-sensing pathways and regulating the release of some virulence factors. However, the detailed role of Qrr sRNAs in the virulence of Vibrio parahaemolyticus remains poorly understood. In this study, we identified a Vibrio sRNA Qrr5 that positively regulates cytotoxicity and adherence in Caco-2 cells by primarily regulating the T3SS1 gene cluster. A number of 185, 586, 355, and 74 differentially expressed genes (DEGs) detected at 0, 2, 4, and 6 h post-infection, respectively, were mainly associated with ABC transporters and two-component system pathways. The DEGs exhibited a dynamic change in expression at various time points post-infection owing to the deletion of Qrr5. Accordingly, 17 related genes were identified in the co-expression network, and their interaction with Qrr5 was determined based on weighted co-expression network analysis during infection. Taken together, our results provide a comprehensive transcriptome profile of V. parahaemolyticus during infection in Caco-2 cells.
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Right here, flower-like FeMoO4@1T-MoS2 composites were prepared by modifying FeMoO4 microspheres with two-dimensional lamellar 1T-MoS2 as co-catalyst, which was used for photo-Fenton catalysis degradation of binary dyes mixed with methylene blue (MB) and rhodamine B (RhB). Then various parameters affecting the generation of ·OH in the system were investigated. Systematic research shows that the degradation efficiency of MB and RhB can reach 99.8% in 18 min when the Mo/Fe molar ratio of the composite is 1:1. Furthermore, these experiments data were fitted by pseudo-first order kinetics model and pseudo-second order kinetics model. Subsequently the density functional theory (DFT) simulation results showed that FeMoO4 exhibited excellent adsorption for H2O2, and the introduction of 1T-MoS2 played a certain role in the adsorption and activation of H2O2. Finally, the degradation pathways of MB and RhB were proposed to determine intermediates during photo-Fenton process by LC-MS and the reaction mechanism was detailed investigated by quenching experiment of active free radicals. FeMoO4@1T-MoS2 has also excellent stability and highlights the potential and prospect of the composite for dye wastewater treatment.
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Corantes , Peróxido de Hidrogênio , Catálise , Ferro , Azul de Metileno , Molibdênio , OxirreduçãoRESUMO
Foodborne illnesses caused by Salmonella represent a significant public health problem worldwide. The aim of this study was to establish multiplex PCR (mPCR) for the rapid identification of Salmonella serogroups B, C1, C2, D, and E as well as for the serovars enteritidis and typhimurium. Employing pan-genome analysis and PCR verification, B-rfbJ, C1-9679, C2-pimB, D-rfbJ, E-rfbC, and four genes (SE18636, SE16574, SE2599, and SE13329) were identified as specific target genes for Salmonella serogroups B, C1, C2, D, E, and S. enteritidis, respectively. Thereafter, three novel mPCR assays (one of 3-mPCR and two of 2-mPCR) were successfully developed to identify these bacteria based on the target genes and another S. typhimurium-specific STM4495 gene. The primers targeting C1-9679, C2-pimB, and E-rfbC genes specific to the serogroups C1, C2, and E, respectively, constituted a 3-mPCR, while the other two 2-mPCRs, respectively, consisting primers specific to serogroup D and S. enteritidis (D-rfbJ and SE16574), and serogroup B and S. typhimurium-specific primers (B-rfbJ and STM4495), were also designed. The specificity of each mPCR was further evaluated by using non-target strains. The detection limits of mPCRs were approximately 103-104 CFU mL-1 in pure culture and 104-105 CFU g-1 in spiked chicken meat. In addition, mPCR assays could correctly detect target Salmonella in food samples. These results suggest that specific targets could be mined efficiently through a pan-genome analysis tool, and the novel mPCR assays developed in this study offer a promising technique for rapid and accurate detection of five serogroups of Salmonella (B, C1, C2, D, and E) and two serovars (S. enteritidis and S. typhimurium).
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Reação em Cadeia da Polimerase Multiplex , Salmonella enteritidis , Salmonella enteritidis/genética , SorogrupoRESUMO
Waste residue of Chinese prickly ash seeds were simply treated with aqueous ZnCl2 to prepared the high-performed activated carbon. It was characterized by the methods of XRD, SEM, EDX, FT-IR, BET and XPS. The synergetic adsorption performance of Chinese prickly ash seeds activated carbon for Pb2+, Ni2+ and Acid Orange IΙ (AO) was studied. In the single-component system, the adsorption capacity of Pb2+, Ni2+ and AO were 15.1, 10.7 and 188.4â mg/g, respectively. In the AO-Pb2+ system, the maximum adsorption capacity of Pb2+ and AO were 79.40 and 332.68â mg/g under temperature of 30°C and pH of 5.0, respectively. For AO-Ni2+ system, it was 375.6 and 38.3â mg/g, respectively. The adsorption kinetics was satisfactorily fitted by the pseudo-second-order model. The synergic adsorption process can be smoothly described by the non-modified Sips isotherm.
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Carvão Vegetal , Poluentes Químicos da Água , Adsorção , China , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Poluentes Químicos da Água/análiseRESUMO
Salmonella is a widely distributed foodborne pathogen. The use of Salmonella phages as biocontrol agents has recently gained significant interest. Because the Salmonella genus has high diversity, efforts are necessary to identify lytic Salmonella phages focusing on different serovars. Here, five Salmonella phages were isolated from soil samples, and vB_SalP_TR2 was selected as a novel phage with high lytic potential against the host Salmonella serovar Albany, as well as other tested serovars, including Corvallis, Newport, Kottbus, and Istanbul. Morphological analyses demonstrated that phage vB_SalP_TR2 belongs to the Podoviridae family, with an icosahedral head (62 ± 0.5 nm in diameter and 60 ± 1 nm in length) and a short tail (35 ± 1 nm in length). The latent period and burst size of phage vB_SalP_TR2 was 15 min and 211 PFU/cell, respectively. It contained a linear dsDNA of 71,453 bp, and G + C content was 40.64%. Among 96 putative open reading frames detected, only 35 gene products were found in database searches, with no virulence or antibiotic resistance genes being identified. As a biological control agent, phage vB_SalP_TR2 exhibited a high temperature and pH tolerance. In vitro, it lysed most S. Albany after 24 h at 37°C with multiplicities of infection of 0.0001, 0.001, 0.01, 0.1, 1, 10, and 100. In food matrices (milk and chicken meat), treatment with phage vB_SalP_TR2 also reduced the number of S. Albany compared with that in controls. These findings highlighted phage vB_SalP_TR2 as a potential antibacterial agent for the control of Salmonella in food samples.
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A series of catalysts with different core-shell structures has been successfully prepared by a hydrothermal method. They consisted of CeCoOx @TiO2 (single shell), CeCoOx @Nb2 O5 (single shell) and CeCoOx @Nb2 O5 @TiO2 (double shell) core-shell nanocages and CeCoOx nanocages, in which CeCoOx was the core and TiO2 and Nb2 O5 were shells. The influence of the core-shell structure on the catalytic performance of o-dichlorobenzene was investigated by activity, water-resistance, and thermal stability tests as well as catalyst characterization. The temperatures corresponding to 90 % conversion of o-dichlorobenzene (T90 ) of CeCoOx , CeCoOx @TiO2 , CeCoOx @Nb2 O5 , and CeCoOx @Nb2 O5 @TiO2 catalysts were 415, 383, 362 and 367 °C, respectively. CeCoOx @Nb2 O5 exhibited excellent catalytic activity, mainly owing to the special core-shell structure, large specific surface area, abundant activity of Co3+ , Ce3+ , Nb5+ , strong reducibility, and more active oxygen vacancies. It can be seen that the Nb2 O5 coating can greatly improve the catalytic activity of the catalyst. In addition, due to the protective effect of the TiO2 shell on CeCoOx , CeCoOx @Nb2 O5 @TiO2 catalysts exhibited outstanding thermal and hydrothermal stability for 20â hours. The T90 of CeCoOx @Nb2 O5 @TiO2 was slightly lower than that of CeCoOx @Nb2 O5 , but it had higher stability and hydrothermal stability. Furthermore, possible reaction pathways involving the Mars-van-Krevelen (MvK) and Langmuir-Hinshelwood (L-H) models were deduced based on studies of the temperature-programmed desorption of O2 (O2 -TPD), X-ray photoelectron spectroscopy (XPS), and inâ situ diffuse reflectance FTIR spectroscopy (DRIFTS) characterization.
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S-doped NiFe-based particles were prepared by a solvothermal method and used to degrade methylene blue (MB) aqueous solutions with visible light in a heterogeneous Fenton reaction. The obtained solid samples were characterized by XRD, SEM, TEM, and XPS. It was found that 0.2 g L-1 NiFe2S4 can degrade 99.8% MB solution within 6 min in the presence of 5 mM H2O2 and natural pH. The recycle experiments results indicate that the NiFe2S4 catalyst possessed better stability than NiFe2O4. Furthermore, NiFe2S4 particles can be easily separated from contaminant solution by using a magnet due to their excellent ferromagnetism. COD analysis experiments indicated that the COD removal rate of NiFe2S4 is 73.1% in 30 min. A possible mechanism was proposed, and the degradation products were measured by LC-MS.
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Peróxido de Hidrogênio , Azul de Metileno , Catálise , Ferro , LuzRESUMO
OBJECTIVE: Poststroke cognitive impairment (PSCI) is a serious complication of stroke. The neutrophil-to-lymphocyte ratio (NLR) is a marker of peripheral inflammation. The relationship between the NLR and PSCI is far from well studied, and the thesis of this study was to assess the predictive value of the NLR in patients with PSCI, and establish and verify the corresponding prediction model based on this relationship. METHODS: A total of 367 stroke patients were included in this study. Neutrophils, lymphocytes, and NLRs were measured at baseline, and clinical and neuropsychological assessments were conducted 3 months after stroke. The National Institutes of Health Scale (NIHSS) was used to assess the severity of stroke. A Chinese version of the Mini Mental State Examination (MMSE) was used for the assessment of cognitive function. RESULTS: After three months of follow-up, 87 (23.7%) patients were diagnosed with PSCI. The NLR was significantly higher in PSCI patients than in non-PSCI patients (P < 0.001). Patient age, sex, body mass index, NIHSS scores, and high-density lipoprotein levels also differed in the univariate analysis. In the logistic regression analysis, the NLR was an independent risk factor associated with the patients with PSCI after adjustment for potential confounders (OR = 1.67, 95%CI: 1.21-2.29, P = 0.002). The nomogram based on patient sex, age, NIHSS score, and NLR had good predictive power with an AUC of 0.807. In the validation group, the AUC was 0.816. CONCLUSION: An increased NLR at admission is associated with PSCI, and the model built with NLR as one of the predictors can increase prognostic information for the early detection of PSCI.
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Elemental doping has been proven to be an effective strategy for increasing the catalytic activity and structural stability of Fenton catalysts. Therefore, this work reports that Mn-doped FeS2/Fe2O3 (Mn3O4-FeS2/Fe2O3) has excellent catalytic performance for the degradation of Orange II under simulated solar energy. Degradation experiment results showed that the sample with a manganese-iron molar ratio of 1:2 exhibited higher activity than others. The degradation rate of 20â¯mg/L OII reached 99.0% in 18â¯min under the conditions of 0.3â¯g/L Mn3O4-FeS2/Fe2O3, 5â¯mM H2O2 and pHâ¯=â¯2.8. In addition to, the Mn3O4-FeS2/Fe2O3 catalyst shows good reusability for Orange II and high activity for other dyes (MB, MG, Rh B and MO) under optimal conditions. Degradation mechanism study indicated that the heterogeneous Fenton reaction was promoted by retarding the recombination of photogenerated charge carriers and accelerating the cycle between Fe3+/Mn2+ and Fe2+/Mn3+, which improved photo-Fenton-like catalytic performance, resulting in the enhanced degradation of organic pollutant. Finally, a possible degradation pathway was proposed according to the results of liquid chromatography-mass spectrometry (LC-MS). In short, the catalyst has potential application value in wastewater treatment.
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Compostos Azo , Peróxido de Hidrogênio , Benzenossulfonatos , CatáliseRESUMO
Oil/water separation is of great importance for the treatment of oily wastewater, including immiscible light/heavy oil-water mixtures, oil-in-water or water-in-oil emulsions. Smart surfaces with responsive wettability have received extensive attention especially for controllable oil/water separation. However, traditional smart membranes with a switchable wettability between superhydrophobicity and superhydrophilicity are limited to certain responsive materials and continuous external stimuli, such as pH, electrical field or light irradiation. Herein, a candle soot coated mesh (CSM) with a larger pore size and a candle soot coated PVDF membrane (CSP) with a smaller pore size with underwater superoleophobicity and underoil superhydrophobicity were successfully fabricated, which can be used for on-demand immiscible oil/water mixtures and surfactants-stabilized oil/water emulsion separation, respectively. Without any continuous external stimulus, the wettability of our membranes could be reversibly switched between underwater superoleophobicity and underoil superhydrophobicity simply by drying and washing alternately, thus achieving effective and switchable oil/water separation with excellent separation efficiency. We believe that such smart materials will be promising candidates for use in the removal of oil pollutants in the future.
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Oil-polluted water has become a worldwide problem due to increasing industrial oily wastewater as well as frequent oil-spill pollution. Compared with underwater superoleophobic (water-removing) filtration membranes, superhydrophobic/superoleophilic (oil-removing) materials have advantages as they can be used for the filtration of heavy oil or the absorption of floating oil from water/oil mixtures. However, most of the superhydrophobic materials used for oil/water separation lose their superhydrophobicity when exposed to hot (e.g. >50 °C) water and strong corrosive liquids. Herein, we demonstrate superhydrophobic overlapped candle soot (CS) and silica coated meshes that can repel hot water (about 92 °C) and strong corrosive liquids, and were used for the gravity driven separation of oil-water mixtures in hot water and strong acidic, alkaline, and salty environments. To the best of our knowledge, we are unaware of any previously reported studies on the use of superhydrophobic materials for the separation of oil from hot water and corrosive aqueous media. In addition, the as-prepared robust superhydrophobic CS and silica coated meshes can separate a series of oils and organic solvents like kerosene, toluene, petroleum ether, heptane and chloroform from water with a separation efficiency larger than 99.0%. Moreover, the as-prepared coated mesh still maintained a separation efficiency above 98.5% and stable recyclability after 55 cycles of separation. The robust superhydrophobic meshes developed in this work can therefore be practically used as a highly efficient filtration membrane for the separation of oil from harsh water conditions, benefiting the environment and human health.
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A simple method was used to generate colorful hydrophobic stearate particles via chemical reactions between inorganic salts and sodium stearate. Colored self-cleaning superhydrophobic coatings were prepared through a facile one-step spray-coating process by spraying the stearate particle suspensions onto stainless steel substrates. Furthermore, the colorful superhydrophobic coating maintains excellent chemical stability under both harsh acidic and alkaline circumstances. After being immersed in a 3.5 wt % NaCl aqueous solution for 1 month, the as-prepared coatings remained superhydrophobic; however, they lost their self-cleaning property with a sliding angle of about 46 ± 3°. The corrosion behavior of the superhydrophobic coatings on the Al substrate was characterized by the polarization curve and electrochemical impedance spectroscopy (EIS). The electrochemical corrosion test results indicated that the superhydrophobic coatings possessed excellent corrosion resistance, which could supply efficient and long-term preservation for the bare Al substrate.
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Cor , Corrosão , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Propriedades de SuperfícieRESUMO
In this work, a facile and inexpensive one-step sonochemistry irradiation method was developed for the fabrication of SiO2 nanoparticles functionalized with octadecyltrimethoxysilane and their in situ incorporation into cotton fabrics. The double sides of as-prepared fabrics show both superhydrophobic and superoleophilic properties simultaneously with a high water contact angle of 159 ± 1° and an oil contact angle of 0°. Thus, it can be used to separate and capture a series of oils from water, like kerosene, toluene and chloroform, etc. In addition, the as-prepared fabrics still have superhydrophobicity with a water contact angle of above 150° after 40 separation cycles with the separation efficiency for the kerosene-water mixture always above 94.6%. More importantly, the as-prepared fabrics showed robust and stable superhydrophobic properties towards hot water, many corrosive solutions (acidic, basic, salt liquids) and mechanical abrasion. Therefore, this reported fabric has the advantages of scalable fabrication, high separation efficiency, stable recyclability, and excellent durability, exhibiting the strong potential for industrial production.
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In this paper, tunable adhesive superhydrophobic ZnO surfaces have been fabricated successfully by spraying ZnO nanoparticle (NP) suspensions onto desired substrates. We regulate the spray-coating process by changing the mass percentage of hydrophobic ZnO NPs (which were achieved by modifying hydrophilic ZnO NPs with stearic acid) in the hydrophobic/hydrophilic ZnO NP mixtures to control heterogeneous chemical composition of the ZnO surfaces. Thus, the water adhesion on the same superhydrophobic ZnO surface could be effectively tuned by controlling the surface chemical composition without altering the surface morphology. Compared with the conventional tunable adhesive superhydrophobic surfaces, on which there were only three different water sliding angle values: lower than 10°, 90° (the water droplet is firmly pinned on the surface at any tilted angles), and the value between the two ones, the water adhesion on the superhydrophobic ZnO surfaces has been tuned effectively, on which the sliding angle is controlled from 2 ± 1° to 9 ± 1°, 21 ± 2°, 39 ± 3°, and 90°. Accordingly, the adhesive force can be adjusted from extremely low (â¼2.5 µN) to very high (â¼111.6 µN). On the basis of the different adhesive forces of the tunable adhesive superhydrophobic surfaces, the selective transportation of microdroplets with different volumes was achieved, which has never been reported before. In addition, we demonstrated a proof of selective transportation of microdroplets with different volumes for application in the droplet-based microreactors via our tunable adhesive superhydrophobic surfaces for the quantitative detection of AgNO3 and NaOH. The results reported herein realize the selective transportation of microdroplets with different volumes and we believe that this method would potentially be used in many important applications, such as selective water droplet transportation, biomolecular quantitative detection and droplet-based biodetection.
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Nanopartículas/química , Óxido de Zinco/química , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Difração de Raios XRESUMO
A series of anion-cation modified palygorskites were prepared by microwave irradiation, and characterized with FT-IR. Compared with natural palygorskite, the p-nitrophenol sorption capacity with anion-cation modified palygorskite was significantly improved. The maximum sorption capacity (137.74 mg g(-1)) was obtained with the mass ratio 1:4 and 3:10 of hexadecyltrimethylammonium bromide to sodium dodecyl sulfate and the surfactant to palygorskite of at 313 K. The sorption equilibrium was in accordance with the Langmuir isothermal sorption equations. Thermodynamic function calculated showed that the sorption was a spontaneous and exothermic process. Free energy of the sorption increased with the increase of the temperature. The sorption of p-nitrophenol followed the pseudo-second-order process (sorption rate constant: 0.00453 mg(-1)min(-1)).