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1.
J Leukoc Biol ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315716

RESUMO

The mechanism underlying autophagy in paroxysmal nocturnal hemoglobinuria (PNH) remains largely unknown. We previously sequenced the entire genome exon of the CD59- cells from 13 patients with PNH and found genes such as CUX1 encoding Cut-like homeobox 1. Peripheral blood samples from nine patients with PNH and seven healthy controls were obtained to measure CUX1 expression. The correlation between CUX1 mRNA expression and PNH clinical indicators was analyzed. To simulate CUX1 expression in patients with PNH, we generated a panel of PNH cell lines by knocking out PIGA in K562 cell lines and transfected lentivirus with CUX1. CCK-8 and EDU assay assessed cell proliferation. Western blotting was used to detect Beclin1, LC3A, LC3B, ULK1, PI3K, AKT, p-AKT, mTOR, and p-mTOR protein levels. Autophagosomes were observed with transmission electron microscopy. Chloroquine was used to observe CUX1 expression in PNH after autophagy inhibition. Leukocytes from patients with PNH had lower levels of CUX1 mRNA expression and protein content than healthy controls. The lactose dehydrogenase level and the percentage of PNH clones were negatively correlated with CUX1 relative expression. We reduced CUX1 expression in a PIGA-knockout K562 cell line, leading to increased cell proliferation. Levels of autophagy markers Beclin1, LC3B, LC3A and ULK1 increased, and autophagosomes increased. Furthermore, PI3K/AKT/mTOR protein phosphorylation levels were lower. CUX1 expression did not change and cell proliferation decreased in CUX1 knocked down PNH cells after inhibition of autophagy by chloroquine. In brief, CUX1 loss-of-function mutation resulted in stronger autophagy in PNH.

2.
Heliyon ; 9(11): e21863, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027722

RESUMO

Purpose: This report describes a case of interface fluid syndrome (IFS) secondary to Posner Schlossman Syndrome (PSS) following small incision lenticule extraction (SMILE) surgery. Case presentation: A 19-year-old male was diagnosed with IFS secondary to PSS in his left eye 1 month after undergoing SMILE. Detailed patient history and clinical findings, auxiliary examination results, and short-term follow-up are reported. In this patient, the IFS was caused by elevated intraocular pressure (IOP) due to PSS. Treatment with topical steroids in combination with anti-glaucoma drops led to complete regression of the fluid, and there was no recurrence during a 7-month follow-up period. Conclusion: IFS is a potential complication of SMILE, and anterior segment ocular coherence tomography (AS-OCT) can definitively diagnose the condition. This case demonstrates that the treatment for IFS should be based on the underlying cause, and requires prompt and vigorous management for resolution.

3.
Materials (Basel) ; 16(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37570044

RESUMO

Tetracycline (TC) and arsenic contaminants are two main pollutants in aquaculture and livestock husbandry, and they have drawn worldwide attention. To address this issue, a novel N-doped carbon@magnesium silicate (CMS) was fabricated via a facile and low-cost hydrothermal route, adopting glucose and ammonia as C and N sources, respectively. The synergetic combination of carbon and magnesium silicate makes CMS possess a high surface area of 201 m2/g and abundant functional groups. Due to the abundant C- and N-containing functional groups and Mg-containing adsorptive sites, the maximum adsorption capacity values of CMS towards As(V) and TC are 498.75 mg/g and 1228.5 mg/g, respectively. The type of adsorption of As(V) and TC onto CMS is monolayer adsorption. An adsorption kinetic study revealed that the mass transfer and intraparticle process dominates the sorption rate of As(V) and TC adsorption onto CMS, respectively. Various functional groups synthetically participate in the adsorption process through complexion, π-π EDA interactions, and hydrogen bonds. This work provides a one-step, low-cost route to fabricate a N-doped carbonaceous adsorbent with a high surface area and abundant functional groups, which has great potential in the application of practical sewage treatment.

4.
J Colloid Interface Sci ; 652(Pt A): 218-230, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37595439

RESUMO

Design and fabrication of feasible remediation composites for total Cr (Cr(T)) removal is still challenging but urgently required. Herein, eco-friendly expanded vermiculite (VE) is integrated with a photoactive covalent organic framework (COF) polymer, in which photoinduced electrons of surface anchored COF can freely transfer to Cr(VI) for chemical reduction, and layered expanded VE allows ion exchange between resultant Cr(III) cations and interlayered K+, Ca2+, Mg2+, Na+, etc. The Cr(T) removal capacities of the surface-modified VE with important parameters (solution pH value, initial Cr(VI) concentration, etc.) are discussed extensively to understand how to select the best conditions for optimum Cr(T) removal performance. More interestingly, from a circular economy view point, spent Cr-loading VE-based waste can serve as a photocatalyst towards oxidation conversion of ciprofloxacin and NO gas subsequently. Explanations for different effects on physicochemical properties as well as catalytic activities of the reused Cr-loading waste are given. This strategy could provide valuable and promising contribution towards the development of sustainable low-cost mineral materials for Cr(T) removal. These findings also shed new light on the research of recycling spent photocatalyst for resource and reutilization.

5.
Int Immunopharmacol ; 115: 109468, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36608443

RESUMO

Paroxysmal nocturnal haemoglobinuria (PNH) is a clonal disorder of haematopoietic stem cells caused by somatic PIGA mutations, resulting in a deficiency in glycosylphosphatidylinositol-anchored proteins (GPI-AP). Some researchers uncovered that PNH cells displayed a GPI-mediated defect in lipid-raft formation. However, Lipid rafts play a crucial role in signaling, the signaling underlying lipid rafts in PNH have not yet been addressed. In this study, we reported that, IFN-α was significantly increased in PNH plasma compared with normal controls. And PNH cells more resistant to the inhibitory colony[1]-forming activity of IFN-α. Here we have already established PIGA knock out K562 cell line by CRISPR/cas9, the most recognized in vitro model of PNH. PNH cells showed obviously defected endocytosis of IFNα/ßRs in lipid rafts, causing suppressed STAT2 activation and the inflammatory response. We further investigated the possible mechanisms of interferon signaling endosomes mediate by cavin1. Our findings provide crucial insight into the process of reduced IFNα signal transduction in PNH cells mediated by lipid rafts and suggest that cavin1 are a potential target for suppression of IFN-α inflammatory signaling. These results might further explain the growth advantage of PNH cells in an unfavorable microenvironment.


Assuntos
Hemoglobinúria Paroxística , Humanos , Endossomos/metabolismo , Células-Tronco Hematopoéticas , Hemoglobinúria Paroxística/genética , Hemoglobinúria Paroxística/metabolismo , Microdomínios da Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/metabolismo , Interferon-alfa/metabolismo
6.
Front Chem ; 10: 955065, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910723

RESUMO

Graphitic carbon nitride (g-C3N4) photocatalysis for water splitting is harvested as a fascinating way for addressing the global energy crisis. At present, numerous research subjects have been achieved to design and develop g-C3N4 photocatalysis, and the photocatalytic system still suffers from low efficiency that is far from practical applications. Here, there is an inspiring review on the latest progress of the doping strategies to modify g-C3N4 for enhancing the efficiency of photocatalytic water splitting, including non-metal doping, metal doping, and molecular doping. Finally, the review concludes a summary and highlights some perspectives on the challenges and future research of g-C3N4 photocatalysts.

7.
J Colloid Interface Sci ; 622: 1008-1019, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35567949

RESUMO

The spent adsorbent loaded by toxic metals is a solid hazardous waste which could cause significant secondary pollution due to potential possible additional release of metal ions. Therefore, the main subject is direct reutilization of spent adsorbents which can further economically and realistically offer new features, like recycling metal adsorbed, or formation of functional SiO2-based nanocomposites. The nanoporous structure and negative surface charges enable steel slag-derived amorphous calcium silicate hydrate (CSH) to retain effectively the incoming metal ions (e. g. Au3+, Ag+, Pd2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Ce3+, Y3+, and Gd3+) by chemisorption. Sparked by natural carbonation 'weathering', which ultimately sequestrates atmospheric CO2 by alkaline silicate minerals to leach calcium from mineral matrix, the decalcification reactions of metal-bearing CSH results in successful recovery of noble metals (Ag, Au, Pd) upon NaOH etching the resultant SiO2 support. Further, SiO2-based heterostructures, containing nanocrystalline metals (e. g. Au0, Ag0, Pd0, Fe0, Co0, Ni0, Cu0, and Zn0) or rare-earth oxides (e. g. CeO2, Y2O3, and Gd2O3), are formed after reduction in H2/Ar (5 vol% H2) flow, which is also very important for the multipurpose immobilization of diverse hybrid materials on SiO2 surface (e. g. Cu0-Ag0@SiO2, Cu0-CeO2@SiO2, and Cu0-Ag0-CeO2@SiO2).


Assuntos
Nanocompostos , Aço , Compostos de Cálcio , Dióxido de Carbono/química , Íons , Metais/química , Minerais , Silicatos/química , Dióxido de Silício
8.
Chemosphere ; 295: 133785, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35104554

RESUMO

Zero-valent iron (Fe0) has been widely used for the reduction of nitrate, but the end reduction product is mainly ammonium. Here, a novel strategy for selective reduction of nitrate (NO3-) to nitrogen gas (N2) with high efficiency and N2 selectivity was investigated using Fe-based material (Fe0-Cu0-CuFe2O4) combined with citric acid (CA) and ultraviolet (UV) irradiation. In this strategy, the nitrate was firstly reduced to nitrite (NO2-) by Fe0-Cu0-CuFe2O4/UV process, and then the produced NO2- could be further reduced to N2 by carbon dioxide anion radicals (CO2•-) which was generated from CA that was added later. In this process, the selective reduction of NO3- to NO2- was a key step. For this purpose, we synthesized Fe0-Cu0-CuFe2O4 composite by simple chemical replacement and in-situ growth process, which made it have a delicate structure with good contact between Cu and Fe and CuFe2O4. The selective reduction of NO3- to NO2- in Fe0-Cu0-CuFe2O4/UV process was due to that the Cu0 was the electron enrichment center and the photo-generated hole could suppress the NO3- reduction to NH4+ by Fe2+. In this proposed strategy, 100% NO3- removal efficiency and 96.3% N2 selectivity were achieved when the initial NO3- concentration was 30 mg N/L and the reduction time was 60 min. The denitrification mechanism of the Fe0-Cu0-CuFe2O4/UV/CA system was proposed.


Assuntos
Nitratos , Nitrogênio , Dióxido de Carbono , Desnitrificação , Nitratos/química , Nitritos , Oxirredução
9.
Materials (Basel) ; 15(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35208052

RESUMO

In this work, a strategy of heat treatment-precipitation has been developed to recycle Ti-containing metallurgical solid waste by forming Ti-embedded MgAl layered double hydroxide (TMA-LDH). This facile and simple route is featured by the dedicated utilization of the composition of slag with high overall recovery efficiency. Importantly, as-obtained product exhibits visible light response distinctly different from that of pristine MA-LDH ascribed to the Fe doping inherited from initial slag. Its mesoporous nanostructure also provides more microchannels for mass and carrier transfer. As such, excellent photocatalytic activity towards degradation of tetracycline hydrochloride is achieved, and 88% removal could be obtained in 60 min. Furthermore, 44% increase in efficiency than that of Ti-excluded LDH also indicates the synergistically promoting effect of Ti incorporation. Mechanism investigation suggests that Ti incorporation regulates the electronic structure of pristine LDH with more active sites, and favors the formation of radicals with improved oxidative ability for photocatalysis.

10.
J Hazard Mater ; 422: 126951, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34449339

RESUMO

An innovative method is created for transforming iron-rich RO phase (MgO0.239FeO0.761) on steel slag surface into nanostructured Mg0.04Fe2.96O4 layer. The phase change process is investigated, and it is found that salicylic acid modification and alkaline roasting procedures remarkably increase the specific surface area from 0.46 m2/g (raw steel slag) to 69.5 m2/g (Mg0.04Fe2.96O4), and the generation of Mg0.04Fe2.96O4 enhances the absorption of visible light and Cr(VI) conversion with 2-times increasement than raw steel slag. Surface complexation between H2C2O4 ligands and Fe metal moiety on Mg0.04Fe2.96O4 induces the intramolecular electron transfer under visible light irradiation based on a ligand-to-metal charge transfer mechanism, thus resulting in Cr(VI) photoreduction, and the catalytic efficiency is above 90% for Cr(VI) (40 mg/L) under inherent pH= 5.5 conditions. Moreover, recyclability tests based on magnetic separation show that the photoreactivity is closely related to Mg content of Mg0.04Fe2.96O4 layer where Mg leaching occurs and finally generates cubic spinel configuration Fe3O4. This work highlights the importance of surface functionalization in post-use phases of steel slag in which surface reactivity and application potential can be greatly altered by chemical exposure history and surface transformations. It also provides valuable references for studying the metastable state mechanism of magnesium ferrite photocatalysts.

11.
Eye Vis (Lond) ; 8(1): 27, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34256866

RESUMO

BACKGROUND: The use of ocular hypotensive drugs has been reported to attenuate myopia progression. This study explores whether brimonidine can slow myopia progression in the guinea pig form-deprivation (FD) model. METHODS: Three-week-old pigmented male guinea pigs (Cavia porcellus) underwent monocular FD and were treated with 3 different methods of brimonidine administration (eye drops, subconjunctival or intravitreal injections). Four different concentrations of brimonidine were tested for intravitreal injection (2 µg/µL, 4 µg/µL, 20 µg/µL, 40 µg/µL). All treatments continued for a period of 21 days. Tonometry, retinoscopy, and A-scan ultrasonography were used to monitor intraocular pressure (IOP), refractive error and axial length (AL), respectively. On day 21, guinea pigs were sacrificed for RNA sequencing (RNA-seq) to screen for associated transcriptomic changes. RESULTS: The myopia model was successfully established in FD animals (control eye vs. FD eye, respectively: refraction at day 20, 0.97 ± 0.18 D vs. - 0.13 ± 0.38 D, F = 6.921, P = 0.02; AL difference between day 0 and day 21, 0.29 ± 0.04 mm vs. 0.45 ± 0.03 mm, F = 11.655, P = 0.004). Among the 3 different brimonidine administration methods, intravitreal injection was the most effective in slowing myopia progression, and 4 µg/µL was the most effective among the four different concentrations of brimonidine intravitreal injection tested. The AL and the refraction of the brimonidine intravitreal injection group was significantly shorter or more hyperopic than those of other 2 groups. Four µg/µL produced the smallest difference in AL and spherical equivalent difference values. FD treatment significantly increased the IOP. IOP was significantly lower at 1 day after intravitreal injections which was the lowest in FD eye of intravitreal injection of brimonidine. At day 21, gene expression analyses using RNA-seq showed upregulation of Col1a1 and Mmp2 expression levels by intravitreal brimonidine. CONCLUSIONS: Among the 3 different administration methods, intravitreal injection of brimonidine was the most effective in slowing myopia progression in the FD guinea pig model. Intravitreal brimonidine at 4 µg/µL significantly reduced the development of FD myopia in guinea pigs. Expression levels of the Col1a1 and Mmp2 genes were significantly increased in the retinal tissues of the FD-Inj-Br group.

12.
Int J Ophthalmol ; 13(12): 1983-1989, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33344200

RESUMO

AIM: To investigate the proportion and characteristic of emmetropia in schoolchildren aged 6-11, especially estimate the normal value of ocular biometric parameters of emmetropia. METHODS: A population-based cross-sectional study was conducted on children aged 6-11y in Shenzhen. Totally, 2386 schoolchildren from two primary schools were involved. The axial length (AL) and the corneal radius of curvature (CRC) were measured by partial coherence laser interferometry. Noncycloplegic refraction and refractive astigmatism (RA) was measured using autorefraction. The axial length-to-corneal radius of curvature ratio (AL/CRC), corneal astigmatism (CA) and spherical equivalent refraction (SER) were calculated. RESULTS: The proportion of emmetropia in elementary school students was 41.30%. This percentage decreased gradually from 6 to 11 years of age and decreased rapidly after 9 years of age. The mean and 95%CI of each parameter were provided for boys and girls aged 6 to 11 years of age with emmetropia according to each age group. The change trend of parameters of boys and girls are similar. After 7 years of age, the AL of non-emmetropia started to increase faster than that of emmetropia. The change trend of AL/CRC was the same as that of AL. The other parameters tend to be stable after 7 years of age. CONCLUSION: The age of 7-9 is an important period for the changes of refractive state and ocular biometric parameters of primary school students, and it is a special focus period for children myopia prevention. The normal value and variation of ocular biometric parameters of emmetropia can provide the basis for the clinical judgment of whether or not children's ocular biometric parameters obtained by single measurement and changes obtained by multiple measurements are abnormal.

13.
J Environ Sci (China) ; 91: 92-104, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32172986

RESUMO

Highly efficient and sustainable conversion technologies to generate uniform sodalite (Na8(AlSiO4)6(OH)2) zeolite microspheres with low-grade waste natural diatomite as raw materials via a solution-mediated crystallization route were developed in the present study. The synthesis process can be considered as an in-situ zeolitization of diatomite precursor without involving any mesoscale template and any post-synthetic modification. The mass ratios of diatomite and AlCl3·6H2O have remarkable effect on the morphology, crystal structure and porosity of sodalite zeolite product. The preferred sodalite microspheres with uniform mesoporous of size 3.5-5.5 nm and large surface area of 162.5 m2/g exhibit well removal performance for heavy metal ions (Pb(II), Cd(II), Zn(II), and Cu(II)), with the highest adsorption abilities for Pb(II) ions of 365 mg/g. In addition, the effect of contact time, initial ion concentration, competitive adsorption and solution pH were evaluated. The removal performance results from synergistic effects of dominating cation-exchange and additional surface chemisorption. The study may broadly help unveil chemical control reactions of the zeolitization processes of diatomite, and thus facilitates the development of promising zeolite materials for the use in natural and engineered aquatic environments by recycling waste diatomite resources.


Assuntos
Metais Pesados , Poluentes Químicos da Água/análise , Zeolitas , Adsorção , Terra de Diatomáceas , Concentração de Íons de Hidrogênio , Microesferas
14.
Cornea ; 38(4): 446-453, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30840609

RESUMO

PURPOSE: To evaluate the feasibility and efficacy of small-incision femtosecond laser-assisted intracorneal concave lenticule implantation (SFII) and penetrating keratoplasty (PKP) in patients with progressive keratoconus. METHODS: All the patients were clinically diagnosed with progressive keratoconus. Twenty patients underwent PKP (PKP group), and 11 patients underwent SFII (SFII group). Visual acuity, intraocular pressure, corneal topography, corneal visualization Scheimpflug technology, anterior segment optical coherence tomography, and in vivo confocal microscopy were analyzed. RESULTS: Vision improved at 3 months postoperatively in the SFII group. In the PKP group, corrected distance visual acuity improved 1 week after surgery. Corneal topography showed a statistically significant decrease in the anterior K1 and K2. Corneal visualization Scheimpflug technology showed that changes in the biomechanical parameters of the SFII group were also statistically different from those of the PKP group. All the grafts from both groups were clearly visible by anterior segment optical coherence tomography observation. The central corneal thickness of both groups was stable during the 24-month study period. In vivo confocal microscopy showed a few dendritic cells in the subepithelial region in the SFII group. At 3 months after surgery, many dendritic cells and inflammatory cells were observed in the basal epithelium and stroma in the PKP group. CONCLUSIONS: Both SFII and PKP surgical procedures resulted in a stable corneal volume and improved visual acuity in this long-term study. SFII was less invasive and more efficient compared with PKP.


Assuntos
Cirurgia da Córnea a Laser/métodos , Ceratocone/cirurgia , Ceratoplastia Penetrante/métodos , Adolescente , Adulto , Córnea/patologia , Topografia da Córnea , Feminino , Humanos , Pressão Intraocular/fisiologia , Ceratocone/fisiopatologia , Masculino , Refração Ocular/fisiologia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Adulto Jovem
15.
RSC Adv ; 9(7): 3816-3827, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35518093

RESUMO

A general solution-phase strategy is developed to synthesize nanostructure niobates such as MnNb2O6, SnNb2O6 and ZnNb2O6 on natural mineral diatomite for water environmental remediation. (NH4)2C2O4 aqueous solution is the key to achieve a scalable and controllable synthesis of niobate/diatomite hybrid systems, which generates NH3·H2O for surface etching activation of diatomite, and H2C2O4 for complexation dissolution of Nb2O5, enabling the heterogeneous crystallization process to proceed with controllable growth kinetics. First principle calculations indicate that both niobium atom and niobium-oxygen species have the lowest adsorption energy on SiO2 surface, and then induce the nucleating process of Nb-O-Mn (or Zn, Sn) networks. Cr(vi), Fe(iii), and Pb(ii) ions are taken as target pollutants to evaluate the water-cleaning ability of the niobate-modified diatomite. Possible mechanisms for the photoreduction of Cr(vi), physical adsorption of Fe(OH)3 colloids, and chemisorption of Pb(ii) ions are proposed on the basis of experimentally investigations. The possibility of combining the advantages of natural mineral diatomite and nanostructured niobates provides a highly robust and potential material system with versatile functionalities of heavy metal ion removal, demonstrating great promise for a wide range of water purification.

16.
J Environ Sci (China) ; 66: 358-367, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29628105

RESUMO

Niobium oxide nanowire-deposited carbon fiber (CF) samples were prepared using a hydrothermal method with amorphous Nb2O5·nH2O as precursor. The physical properties of the samples were characterized by means of numerous techniques, including X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), UV-visible spectroscopy (UV-vis), N2 adsorption-desorption, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy. The efficiency for the removal of Cr(VI) was determined. Parameters such as pH value and initial Cr(VI) concentration could influence the Cr(VI) removal efficiency or adsorption capacity of the Nb2O5/carbon fiber sample obtained after hydrothermal treatment at 160°C for 14hr. The maximal Cr(VI) adsorption capacity of the Nb2O5 nanowire/CF sample was 115mg/g. This Nb2O5/CF sample also showed excellent photocatalytic activity and stability for the reduction of Cr(VI) under UV-light irradiation: the Cr(VI) removal efficiency reached 99.9% after UV-light irradiation for 1hr and there was no significant decrease in photocatalytic performance after the use of the sample for 10 repeated cycles. Such excellent Cr(VI) adsorption capacity and photocatalytic performance was related to its high surface area, abundant surface hydroxyl groups, and good UV-light absorption ability.


Assuntos
Carbono/química , Cromo/química , Nanofios/química , Nióbio/química , Óxidos/química , Adsorção , Fibra de Carbono , Modelos Químicos , Processos Fotoquímicos , Poluentes Químicos da Água
17.
RSC Adv ; 8(3): 1621-1631, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35540873

RESUMO

A novel rod-shaped MoO2/CaSO4 composite was prepared by using hexa-ammonium molybdate and flue gas desulfurization gypsum via a simple mixed-solvothermal route. In this composite, CaSO4 matrices are decorated with MoO2 nanoparticles, and non-structural mesopores are formed via particle packing. Moreover, it displays an excellent adsorption capability towards anionic congo red (CR) and cationic rhodamine B (RhB). The adsorption quantities per unit mass and removal efficiencies of the two dyes are significantly influenced by adsorbent dose, solution pH, and temperature. The adsorption isotherm data can be best fitted by the Langmuir model, and the calculated maximum adsorption quantities at 303.5 K are 853.54 mg g-1 for CR and 86.38 mg g-1 for RhB, respectively, which are superior to other common adsorbents. The corresponding kinetic data can be well matched with the pseudo-second-order model. Additionally, the CR adsorption is an exothermic process, while the RhB adsorption is an endothermic process. Both of them are multi-step chemisorption processes influenced by surface adsorption and intra-particle diffusion. This MoO2/CaSO4 composite can be applied as an alternative adsorbent for removing organic dyestuffs from printing and dyeing wastewater.

18.
Curr Eye Res ; 41(9): 1202-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26833247

RESUMO

PURPOSE: To assess and compare the dry-eye-associated parameters and corneal biomechanical status after small-incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). METHODS: Sixty-five patients' (128 eyes) were collected between November 2012 and April 2013. Thirty-five (69 eyes) underwent SMILE and thirty (59 eyes) underwent FS-LASIK. Visual acuity, manifest refraction, tear break-up time (TBUT), Schirmer's test (ST), corneal sensitivity, Ocular Surface Disease Index (OSDI), corneal hysteresis (CH) and corneal resistance factor (CRF) were evaluated preoperatively and 1 day, 1 week, 1 month, 3 and 6 months postoperatively. RESULTS: There was no significant difference in visual outcomes of SMILE and FS-LASIK (p = 0.208). TBUT, ST, CH and CRF decreased significantly after surgery in both groups (all p < 0.05); however, the decrease of TBUT, ST and CRF in the SMILE group was not as significant as that in the FS-LASIK group (all p < 0.05) and the change of CH value was comparable in both groups (p = 0.052).Corneal sensitivity was significantly decreased in the FS-LASIK group postoperatively (p < 0.05), but not significantly changed in the SMILE group (p > 0.05). OSDI scores were significantly increased after surgery for the two groups (all p < 0.05), and the scores were much higher in the FS-LASIK group than in the SMILE group (p = 0.000). CONCLUSION: The corneal biological healing of SMILE surgery was superior to FS-LASIK in the early period.


Assuntos
Córnea/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Refração Ocular , Cicatrização , Adulto , Fenômenos Biomecânicos , Córnea/patologia , Córnea/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Miopia/patologia , Miopia/fisiopatologia , Período Pós-Operatório , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
19.
J Environ Sci (China) ; 29: 71-81, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25766015

RESUMO

Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). The wire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g.


Assuntos
Cromo/química , Terra de Diatomáceas/química , Compostos de Manganês/química , Óxidos/química , Poluentes Químicos da Água/química , Adsorção , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
20.
J Nanosci Nanotechnol ; 13(8): 5452-60, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23882778

RESUMO

A swift and efficient approach to converting organic dye effluents into fresh water could be of substantial benefit. In this study, we presented facile hydrothermal synthesis of K1.33Mn8O16 nanowires in ammonium fluoride (NH4F) aqueous solution. The crystallization process of K1.33Mn8O16 nanowires was investigated. The as-obtained K1.33Mn8O16 nanowires were used for swift adsorptive removal of Congo red from aqueous solution without adjusting pH value at room temperature. Adsorption kinetic experimental data are well described by pseudo-second-order rate kinetic model, and the adsorption isotherm fits Langmuir isotherm model. The present investigation provides an efficient approach to designing and fabricating manganese-based nanomaterials for environmental remediation.


Assuntos
Adsorção , Vermelho Congo/isolamento & purificação , Nanotecnologia/métodos , Nanofios/química , Peróxidos/química , Água/química , Compostos de Amônio , Corantes/isolamento & purificação , Fluoretos/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Modelos Químicos , Compostos Orgânicos/análise , Compostos de Amônio Quaternário/química , Temperatura , Fatores de Tempo , Purificação da Água/instrumentação , Purificação da Água/métodos , Abastecimento de Água , Difração de Raios X
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