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3.
Carbohydr Polym ; 261: 117894, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766379

RESUMO

The advent of electric skins (E-skin) with tactile sensation, flexibility, and human affinity characteristics have attracted considerable attention in extensive research fields, including intelligent robots and health monitoring, etc. To improve the intrinsic brittleness of hydrogels, a multifunctional E-skin was fabricated involving a TEMPO-NFC and a covalently cross-linked polyacrylamide (PAM) network. In this work, silver nanoparticles (AgNPs) as long-term antibacterial agent and conductive fillers were coated onto NFC nanofibers. Subsequently, this nanocomposite hydrogel was synthesized by free radical copolymerization of AM monomers with PNAg fibers as interpenetrating fibers network. Importantly with NFC present, the nanocomposite hydrogel exhibited superior mechanical performance and excellent self-recovery ability. The obtained sensor with excellent mechanical stability and sensing performance could detect mechanotransduction signal of human movements. This work provides a practicable method to prepare high antibacterial efficiency, excellent mechanical performance, and dual-modal nanocellulose-based hydrogel sensor for the broad-range application in human-motion detection and intelligence skins.

4.
Neural Plast ; 2021: 8819169, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763127

RESUMO

Introduction: We studied the impact of vibratory stimulation on the electrophysiological features of digital sensory nerve action potential (SNAP). Methods: The antidromic digit 3 SNAP was recorded in 19 healthy adults before, during, and after applying a vibration to either 3rd or 5th metacarpal phalangeal joint (MCPJ) at 60 Hz and amplitude of 2 mm. 100% supramaximal stimulus intensity was performed in 5 subjects (randomly selected from the 19 subjects) where the SNAP sizes were recorded. Results: The amplitude of digit 3 SNAP declined to 58.9 ± 8.6% when a vibration was applied to MCPJ digit 3. These impacts did not change by increasing the electrical stimulus intensity. The SNAP regained its baseline value immediately after the cessation of vibration stimulation. The magnitude of size reduction of digit 3 SNAP was less when vibration was moved to from MCPJ of digit 3 to MCPJ of digit 5. Discussion. The marked drop of the SNAP size during vibratory stimulation reflects the decreased responsiveness of Aß afferents to electrical stimulation, which deserve further investigation in the study of focal vibration in neurorehabilitation.

5.
Waste Manag ; 125: 145-153, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33689990

RESUMO

Waste tire was heat-treated to prepare sulfur self-doped chars via pyrolysis and activation processes. Pyrolytic waste tire chars were activated at different temperatures (600 °C, 800 °C, 1000 °C, and 1200 °C) with K2FeO4 additive ratios (mass ratio of K2FeO4 to char) being 0.5, 1, 2, and 3, respectively. The effective activation occurred over 600 °C with K2FeO4 additive ratios over 0.5. The strongest activation occurred at 1000 °C with K2FeO4 additive ratio of 3, and the specific capacitance increased to 129.5 F/g at 1 A/g, which was six times higher than that without K2FeO4. The activation mechanism revealed that higher K2FeO4 additive ratio promoted the transformation of large aromatic ring systems (≥6 rings) to small ones and smaller pores formation. When K2FeO4 additive ratio was less than 2, high ratio not only promoted alkyl-aryl C-C bonds formation, but also inhibited sulfur enrichment with S 2p3/2 (sulphide bridge) converting to S 2p5/2 (sulphone bridge). But when the ratio was further increased, slight decomposition of alkyl-aryl C-C bonds with the promoted conversion of S 2p5/2 to S 2p3/2 was witnessed. Furthermore, higher activation temperature promoted the conversion of aromatic ring systems and alkyl-aryl C-C bonds to form ordered graphitic structures. S 2p3/2 was enriched before 800 °C, but both S 2p3/2 and S 2p5/2 were released at higher temperature. Formation of smaller pores was promoted before 1000 °C, but the char structure was then destroyed to form larger pores when temperature was further increased.


Assuntos
Temperatura Alta , Pirólise , Enxofre , Temperatura
6.
Zhongguo Zhong Yao Za Zhi ; 46(6): 1438-1449, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33787142

RESUMO

In order to better utilize saffron floral bio-residues(SFB), a qualitative and quantitative analysis of flavonoids in SFB was conducted using UPLC-MS and UPLC, respectively. On the one hand, 50 flavonols and 5 anthocyanins were putatively characte-rized by using UPLC-Q-TOF-MS. On the other hand, an UPLC method was established for determining the fingerprint of SFB as well as testing the main flavonoids kaempferol-3-O-sophoroside and delphinidin-3,5-di-O-glucoside. Contents of kaempferol-3-O-sophoroside and delphinidin-3,5-di-O-glucoside of 10 batches of samples were 44.21-58.73 mg·g~(-1) and 2.11-6.37 mg·g~(-1), respectively, and the similarities of 10 batches were more than 0.99. In addition, the color of the samples was digitized by using electronic eye technology, and it was found that the color of the samples was significantly correlated with the content of delphinidin-3,5-di-O-glucoside. The richness of flavonoids in SFB indicated its potential for development and utilization, and the large variation in anthocyanin content among samples from different regions suggested that more attention should be paid to the methods of sample pretreatment and storage.


Assuntos
Crocus , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Flavonoides , Flores , Espectrometria de Massas em Tandem
7.
Zhongguo Zhong Yao Za Zhi ; 46(2): 454-466, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33645135

RESUMO

In this study, Honghua Injection, Danshen Injection, Shenkang Injection, Shuxuetong Injection, Lulutong Injection, Shenxiong Glucose Injection and Chuanxiong Injection were compared for their clinical efficacy on chronic renal insufficiency by using the method of network Meta-analysis, with Western medicine as the common reference. The randomized controlled trial(RCT) of Hong-hua Injection, Danshen Injection, Shenkang Injection, Shuxuetong Injection, Lulutong Injection, Shenxiong Glucose Injection and Chuanxiong Injection for the treatment of chronic renal insufficiency were obtained by computer-based retrieval. The literature quality was evaluated by using the method in Cochrane Reviewer's Handbook 5.1 after independent screening of the included literature by two reviewers. The RJAGS package and GEMTC package of RevMan 5.3, GEMTC software, R software were used for statistical analysis to compare and sort the different injections in terms of efficacy. A total of 6 197 patients with chronic renal failure were included in 79 RCTs, involving 8 treatment measures. The effective rates of conventional treatment combined with Shenxiong Injection(OR=3.55, 95%CI[1.98, 6.37], P<0.000 1), Honghua Injection(OR=3.77, 95%CI[2.45, 5.81], P<0.000 01), Shuxuetong Injection(OR=6.71, 95%CI[3.30, 13.65], P<0.000 01) and Shenkang Injection(OR=4.14, 95%CI[3.42, 5.03], P<0.000 01) were all better than that in control group, and the effective rate of Honghua Injection combined with conventional treatment(OR=3.89, 95%CI[1.73, 8.74], P=0.001) was better than that in Danshen Injection combined with conventional treatment, all with statistically significant differences. By comprehensive comparison, Shuxuetong Injection, Honghua Injection and Shenkang Injection combined with Western medicine had good clinical effect on the effective rate, serum creatinine reduction and urea nitrogen reduction in patients with chronic renal insufficiency. However, due to the relatively low quality of the included literature, the conclusion has yet to be verified clinically.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Renal Crônica , Salvia miltiorrhiza , Teorema de Bayes , Humanos , Medicina Tradicional Chinesa , Metanálise em Rede , Insuficiência Renal Crônica/tratamento farmacológico
8.
Sr Care Pharm ; 36(3): 152-158, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662239

RESUMO

OBJECTIVE: To evaluate the prevalence of bisphosphonate use without a drug holiday and to assess the success of an interdisciplinary approach to manage and discontinue bisphosphonate therapy. SETTING: The study was completed at one rural family medicine center. PRACTICE DESCRIPTION: The practice employs two fulltime pharmacists. Clinical pharmacists' responsibilities include chronic care management as well as collaboration with the team during interdisciplinary clinics. Clinical pharmacists frequently collaborate with other professionals on medication evaluations and quality improvement projects. PRACTICE INNOVATION: The pharmacy team and medical resident collaborated to determine appropriateness of bisphosphonate use. This was a two-phase evaluation. In the first phase, therapies were evaluated based on duration and consistency with guideline recommendations based on a retrospective chart review. In the second phase, the pharmacy and medicine team determined if therapy warranted further continuation or if a drug holiday was needed. The team reached out to providers proactively and provided patient and provider education on discontinuing therapy. MAIN OUTCOME MEASUREMENTS: Patient demographics, bisphosphonate regimen and duration of prescription, frequency of drug holidays, and success rate of therapy discontinuation. RESULTS: Bisphosphonates were prescribed for an average of 4.2 years with 56 patients prescribed therapy for >5 years. Twenty-one of the 56 patients had a history of a drug holiday, and 13 of the 35 remaining patients had therapy discontinued or a drug holiday was initiated based on the team's recommendation. Patients were more likely to be prescribed therapy for >5 years if they were older and had more provider appointments.

9.
Biomed Res Int ; 2021: 6636266, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33688498

RESUMO

Objective: To develop and validate a sensitive and rapid ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the determination of enasidenib in rat plasma and to investigate the effect of Xiao-ai-ping injection (XAPI) on the pharmacokinetics of enasidenib in rats. Methods: The rat plasma was precipitated with acetonitrile, enasidenib and internal standard (IS) were separated on an Acquity UPLC BEH C18 column, and acetonitrile and 0.1% formic acid were used as the mobile phase in gradient mode. Enasidenib and IS were monitored and detected by multiple reaction monitoring (MRM) using tandem mass spectrometry in positive ion mode. 12 Sprague-Dawley (SD) rats were randomly divided into control group (group A) and experimental group (group B), 6 rats in each group. Group B was intramuscularly injected with XAPI (0.3 mL/kg) every morning, 7 days in a row. Group A was intramuscularly injected with normal saline, 7 days in a row. On the seventh day, enasidenib (10 mg/kg) was given to both groups 30 min after injection of normal saline (group A) or XAPI (group B), and the blood was collected at different time points such as 0.33, 0.67, 1, 1.5, 2, 3, 4, 6, 9, 12, 24, and 48 h. The concentration of enasidenib was detected by UPLC-MS/MS, and the main parameters of pharmacokinetic of enasidenib were calculated using the DAS 2.0 software. Results: Under the current experimental conditions, this UPLC method showed good linearity in the detection of enasidenib. Interday and intraday precision did not exceed 10%, the range of accuracy values were from -1.43% to 2.76%. The results of matrix effect, extraction recovery, and stability met the requirements of FDA approval guidelines of bioanalytical method validation. The C max of enasidenib in the group A and the group B was (458.87 ± 136.02) ng/mL and (661.47 ± 107.32) ng/mL, t 1/2 was (7.74 ± 0.91) h and (8.64 ± 0.42) h, AUC(0 - t) was (4067.24 ± 1214.36) ng·h/mL and (5645.40 ± 1046.30) ng·h/mL, AUC(0 - ∞) was (4125.79 ± 1235.91) ng·h/mL and (5759.61 ± 1078.59) ng·h/mL, respectively. The C max of enasidenib in group B was 44.15% higher than that in group A, and the AUC(0 - t) and AUC(0 - ∞) of enasidenib in group B were 38.80% and 39.60% higher than that in group A, respectively, and the t 1/2 was prolonged from 7.74 h to 8.64 h. Conclusion: An UPLC-MS/MS method for the determination of enasidenib in rat plasma was established. XAPI can inhibit the metabolism of enasidenib and increase the concentration of enasidenib in rats. It is suggested that when XAPI was combined with enasidenib, the herb-drug interaction and adverse reactions should be paid attention to, and the dosage should be adjusted if necessary.

10.
Eur J Emerg Med ; 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33709993

RESUMO

BACKGROUND: Thiamine and vitamin C have been increasingly used in patients with sepsis or septic shock because of their potential for improving metabolism and reducing mortality. OBJECTIVE: We aim to determine if thiamine combined vitamin C can reduce mortality in patients with sepsis or septic shock. EVIDENCE SOURCES AND STUDY SELECTION: We comprehensively searched the PubMed, Embase, Cochrane Library, and Web of Science databases from their inception dates through 1 January 2021. Literature works evaluating the efficacy of thiamine combined vitamin C in patients with sepsis or septic shock were considered. DATA EXTRACTION AND OUTCOME MEASUREMENTS: Two reviewers extracted data and assessed study quality. A meta-analysis was performed to calculate an odds ratio (OR), 95% confidence intervals (CIs), and P values for in-hospital mortality (primary outcome). Secondary outcomes included duration of ICU stay, duration of hospital stay, duration of vasopressor use, and change in sequential organ failure assessment (SOFA) scores. RESULTS: Seven randomized controlled trials were identified, encompassing a total of 868 patients. There was no statistical difference between groups for in-hospital mortality (OR: 1.11; 95% CI [0.79-1.56]; P = 0.55). Other than improving SOFA score during the first 72 h after enrollment and duration of vasopressor use, we found no other significant associations. CONCLUSIONS: Despite widespread enthusiasm for thiamine combined with vitamin C for sepsis and septic shock, we only found an association with reduced SOFA score and time of vasopressor use. There was no association with in-hospital mortality.

11.
Endocr Pract ; 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33610810

RESUMO

OBJECTIVE: Active surveillance (AS) is a management alternative for patients with low-risk papillary thyroid microcarcinoma (PTMC). To decide the best candidates for AS, clinicians can use a framework to classify PTMC patients as ideal, appropriate, or inappropriate. This study aimed to explore the correlation between the framework categories and surgical pathology. METHODS: This multicenter retrospective study was conducted between 2014 and 2016. We included 1997 patients who underwent thyroid surgery for the first time due to suspected PTMC and were confirmed as PTMC by postoperative pathology. The consistency of modified preoperative risk stratification and the pathologic condition were evaluated using a consistency ratio and the Kappa coefficient. Stratified analysis was also performed to test consistency in different age groups. RESULTS: Based on the decision-making framework, 558 (27.9%) patients could receive AS while 810 (40.6%) patients did not require immediate surgery according to the actual postoperative pathology. The sensitivity, false-positive rate, specificity, false-negative rate, and consistency rate were 82.39%, 56.91%, 43.09%, 17.61%, and 66.45%, respectively. The Kappa value was 0.268. Stratified analysis showed that the sensitivity was 87.7% among patients aged 18 to 59 years. In the group aged ≥60 years, the specificity was up to 87.5%, but the sensitivity was low. CONCLUSION: The results of the modified risk-stratified clinical decision-making framework did not have a high consistency with the postoperative results. However, the framework showed a good effect in selecting patients for immediate surgery in the younger group and patients for AS in the older group.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33522229

RESUMO

Activating upconversion nanoparticle-based photoresponsive nanovectors (UCPNVs) by upconversion visible light at low-power near-infrared (NIR) excitation can realize deeper biotissue stimulation with a minimized overheating effect and photodamage. Here, we demonstrate a facile strategy to construct new surface-decorated UCPNVs based on Passerini three-component reaction (P-3CR) in highly convenient and effective manners. Such UCPNVs materials have a tailored deprotecting wavelength that overlaps upconversion blue light. By using 3-perylenecarboxaldehyde, Tm3+/Yb3+ ion-doped UCNP-containing isocyanides, and antitumor agent chlorambucil as the three components, the resulting monodisperse UCPNV exhibits an efficient release of caged chlorambucil under a very low 976 nm power. This approach expands the synthetic toolbox to enable quick development of UCPNVs for UCNP-assisted low-power NIR photochemistry.

13.
Carbohydr Polym ; 257: 117611, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33541642

RESUMO

The oil/water (o/w) separation is a global challenge because of the increasing water contamination by oil spill accidents, and oil-containing wastewater produced by food, textile, and petrochemical industries. In this study, we have developed bacterial cellulose (BC) based superhydrophilic/underwater superoleophobic (SUS) membrane for o/w separation. The membrane was designed through a facile method by blending BC nanofibers with silica microparticles (SiO2-MPs), which was further modified by bio-inspired polydopamine (PDA) coatings. The composite membrane exhibited SiO2-MPs dependent o/w separation with a high separation efficiency of >99.9 % and a high flux rate of ∼10,660 Lm-2 h-1 while applying a small negative pressure (0.3-0.5 bar). The membrane with different content of SiO2-MPs also showed the potential to separate oil-in-water emulsion with the highest oil rejection of 98.2 % and the highest flux rate of ∼1250 Lm-2 h-1 on an ultra-low pressure <0.1 bar. Moreover, the membrane showed antifouling properties, recyclability, and stability in harsh conditions.

14.
Chem Commun (Camb) ; 57(19): 2392-2395, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33543206

RESUMO

A series of functional IRMOF-3 frameworks with solid-state luminescence and tuneable light emission (from 490 to 608 nm) have been synthesized by per-functionalizing AIE-active Schiff-bases with zinc. These precursor AIE-active ligands endowed the functional frameworks with boosted fluorescence emission efficiencies (from 0.16% to 1.03%). IRMOF-3-h revealed a flower-like morphology attributed to the formation of J-aggregates, and could be used as a fluorescent probe for sensitive detection of copper(ii) (135 pM) and thiols (subnanomole).

15.
J Transl Med ; 19(1): 73, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593392

RESUMO

BACKGROUND: Neurotrophic tropomyosin receptor kinases (NTRKs) are a gene family function as oncogene or tumor suppressor gene in distinct cancers. We aimed to investigate the methylation and expression profiles and prognostic value of NTRKs gene in colorectal cancer (CRC). METHODS: An analysis of DNA methylation and expression profiles in CRC patients was performed to explore the critical methylations within NTRKs genes. The methylation marker was validated in a retrospectively collected cohort of 229 CRC patients and tested in other tumor types from TCGA. DNA methylation status was determined by quantitative methylation-specific PCR (QMSP). RESULTS: The profiles in six CRC cohorts showed that NTRKs gene promoter was more frequently methylated in CRC compared to normal mucosa, which was associated with suppressed gene expression. We identified a specific methylated region within NTRK3 promoter targeted by cg27034819 and cg11525479 that best predicted survival outcome in CRC. NTRK3 promoter methylation showed independently predictive value for survival outcome in the validation cohort (P = 0.004, HR 2.688, 95% CI [1.355, 5.333]). Based on this, a nomogram predicting survival outcome was developed with a C-index of 0.705. Furthermore, the addition of NTRK3 promoter methylation improved the performance of currently-used prognostic model (AIC: 516.49 vs 513.91; LR: 39.06 vs 43.64, P = 0.032). Finally, NTRK3 promoter methylation also predicted survival in other tumors, including pancreatic cancer, glioblastoma and stomach adenocarcinoma. CONCLUSIONS: This study highlights the essential value of NTRK3 methylation in prognostic evaluation and the potential to improve current prognostic models in CRC and other tumors.

16.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1866(5): 158904, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33578049

RESUMO

OBJECTIVE: The purpose of this study was to explore the role of long noncoding RNA (lncRNA) prostate cancer antigen 3 (PCA3) in atherosclerosis and the underlying mechanism. METHODS: The Gene Expression Omnibus (GEO) datasets were used to divide differentially expressed lncRNAs, microRNAs (miRNAs), and mRNAs. The expression of PCA3, miR-140-5p, RFX7 and ABCA1 were determined by qPCR or Western blot in ox-LDL-treated macrophages. Macrophage lipid accumulation s was evaluated using the Oil Red O staining and high-performance liquid chromatography. Target relationships among PCA3, miR-140-5p, RFX7, and ABCA1 promoter area were validated via dual-luciferase reporter gene assay or chromatin immunoprecipitation assay. The apoE-/- mouse model in vivo was designed to evaluate the effect of PCA3 on the reverse cholesterol transport (RCT) and atherosclerosis. RESULTS: PCA3 was down-regulated in foam cells, whereas miR-140-5p was highly expressed. Overexpression of PCA3 promoted ABCA1-mediated cholesterol efflux and reduced lipid accumulation in macrophages. Besides, RFX7 bound to the ABCA1 promoter and increased ABCA1 expression. Targeted relationships and interactions on the expression between miR-140-5p and PCA3 or RFX7 were elucidated. PCA3 up-regulated ABCA1 expression by binding to miR-140-5p to up-regulate RFX7 and ABCA1 expression in macrophages. PCA3 promoted RCT and impeded the progression of atherosclerosis by sponging miR-140-5p in apoE-/- mice. Meanwhile, miR-140-5p also inhibit ABCA1 expression via downregulation of RFX7 to impede RCT and aggravate atherosclerosis. CONCLUSIONS: lncRNA PCA3 promotes ABCA1-mediated cholesterol efflux to inhibit atherosclerosis through sponging miR-140-5p and up-regulating RFX7.

17.
Dalton Trans ; 50(11): 3916-3922, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33635301

RESUMO

Three AIE (aggregation-induced emission)-ESIPT (excited-state intramolecular proton transfer) active 2-(2-hydroxyphenyl)benzothiazole derivatives, HL1, HL2 and HL3 with one, two and three rotatable phenyl groups, were obtained and characterized. Their AIE properties in THF/HEPES solution were investigated in detail. HL2 shows the best AIE performance with 71-fold fluorescence enhancement, while HL3 only shows a 9-fold enhancement. With the AIE property, HL1 and HL2 could act as fluorescence chemosensors to detect Cu2+ ions via the "turn off" mode in THF/HEPES media. With the ESIPT property, HL1 and HL2 could also detect Zn2+ ions via the "turn on" mode in EtOH/HEPES media. During the detection process, both demonstrate rapid response and high contrast before and after the addition of metal ions. The species formed in the detection system were investigated. The results of X-ray single-crystal diffraction confirm that Zn2+ is coordinated with the oxygen atom and Schiff base nitrogen atom instead of the benzothiazole nitrogen atom in the tetrahedron geometry. Moreover, the chemosensors were successfully constructed into handy fluorescence test papers for Cu2+ and Zn2+ detection.

18.
Opt Lett ; 46(3): 604, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33528419

RESUMO

This publisher's note contains corrections to Opt. Lett.46, 290 (2021)OPLEDP0146-959210.1364/OL.412229.

19.
Opt Lett ; 46(2): 290-293, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33449010

RESUMO

At present, most of the gradient metasurfaces used to construct surface plasmon polaritons (SPPs)/spoof SPPs (SSPs) couplers are usually compact metal antennas working under reflection and transmission. In reflection mode, meta-couplers link propagating waves and surface waves (SWs), and SWs will undergo significant scattering before coupling to an Eigen SPP in the target system. In transmission mode, metal meta-couplers will encounter complex multilayer designing at the microwave/terahertz region and metal absorption loss at optical frequencies. In this Letter, to the best of our knowledge, a novel design using dielectric gradient metasurfaces instead of metal metasurface couplers is proposed to excite broadband SSPs on the metal groove array. We demonstrate that the well-designed phase dielectric gradient metasurface converts the normal incident terahertz wave to the predetermined angle in the dielectric substrate and then excites the broadband SSPs with the transmission coupling between the dielectric meta-coupler and SSPs surface. This research may open up new avenues in simple and broadband plane dielectric meta-couplers for SSPs in ultra-thin and compact functional devices for versatile applications.

20.
J Nanosci Nanotechnol ; 21(4): 2203-2211, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33500035

RESUMO

Magnetic CoFe2O4 nanoparticles were successfully manufactured through the process of nitrate combustion using anhydrous ethanol as fuel, they together with their intermediate were characterized by thermo gravimetric (TG) analysis, selected area electron diffraction (SAED), transmission electron microscope (TEM), vibrating sample magnetometer (VSM), and X-ray diffraction (XRD). These results indicated a phenomenon that the magnetic CoFe2O4 nanoparticles could be formed at 400 °C, the average grain size, the specific magnetization, and the specific surface area of magnetic CoFe2O4 nanoparticles fabricated at 400 °C for 2 h with 30 mL anhydrous ethanol were corresponding 20 nm, 78.0 Am²/kg and 83.2 m²/kg. Magnetic CoFe2O4 nanoparticles were in application to adsorb methyl blue (MB) of wastewater, and their adsorption performances and electrochemical properties were investigated, the adsorption process data well agreed with the pseudo-second-order kinetics model in concentration ranging from 100 mg/L to 400 mg/L of MB. Compared with Freundlich model, Langmuir model (correlation coefficient R² = 0.9976) could evaluate the adsorption equilibrium state of MB onto CoFe2O4 nanoparticles at indoor temperature, so the monomolecular layer adsorption mechanism was demonstrated to be the mechanism of the MB molecules' adsorption onto CoFe2O4 nanoparticles.

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