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1.
Biochem Genet ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627316

RESUMO

In the present study, our aim was to explore the role of MUC4 in IL-4-stimulated conjunctival epithelial cells and the underlying mechanisms. Human recombinant IL-4 was employed in human conjunctival epithelial cells (HConEpic) cells, and MUC4 shRNA (sh-MUC4) was constructed to explore the functional role of MUC4. The protein level of MUC4, O-GlcNAc transferase (OGT), O-GlcNAc hydrolase (OGA), zonula occludens 1 (ZO-1), gap junction protein beta 2 (GJB2), claudin-8 (CLDN8), and E-cadherin were detected by Western blot in HConEpic cells, the interaction between MUC4 and OGT/OGA was assessed by co-immunoprecipitation (IP) and Western blot in 293T cells. Our results showed that IL-4 significantly up-regulated MUC4 and OGT protein levels in HConEpic cells, while down-regulated OGA protein level. Also, IL-4 down-regulated ZO-1, GJB2, CLDN8, and E-cadherin protein levels in HConEpic cells, while which was markedly reversed by sh-MUC4. Additionally, OGT inhibitor significantly reduced MUC4 protein level, and elevated ZO-1, GJB2, CLDN8, and E-cadherin protein levels in HConEpic cells, while OGA inhibitor resulted in the opposite results. Furthermore, in addition to the interaction between OGT/OGA and MUC4, Co-IP and Western blot also revealed the alteration of MUC4 O-GlcNAcylation in 293T cells treated with OGT/OGA inhibitor. Above findings suggested that OGT/OGA inhibitor regulated MUC4 protein level by affecting MUC4 O-GlcNAcylation to regulate ZO-1, GJB2, CLDN8, and E-cadherin protein levels in HConEpic cells, which was achieved via inhibiting the interaction between OGT/OGA and MUC4. This study may provide a better understanding of the pathogenesis of allergic conjunctivitis (AC).

2.
Inorg Chem ; 60(7): 4337-4341, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33749258

RESUMO

Imidazolium-based ionic liquids have been widely applied in the synthesis of organic hybrid chalcogenidometalates, while the other types of ionic liquids are rarely tried. Reported here is the first application of a pyridinium-based ionic liquid in the preparation of two main-group heterometallic selenides featuring isomorphic three-dimensional frameworks. Of particular interest is that three gallium-tin selenides possessing another type of three-dimensional framework have been prepared by replacing the pyridinium-based ionic liquid with imidalolium-based ionic liquids under the same reaction conditions.

3.
Inorg Chem ; 59(4): 2337-2347, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31999443

RESUMO

Thiol-amine solvent mixtures have been widely applied in the solution processing of binary chalcogenide thin films due to their excellent ability to dissolve various bulk binary chalcogenides. However, application of this solvent system in preparing new crystalline chalcogenidometalates has not been explored. In this work, by using a thiol-amine solvent mixture of n-butylamine (BA) and 1,2-ethanedithiol (EDT) as the reaction medium and protonated piperazine (pip) cation as the template, we synthesized a series of new chalcogenidoarsenates with structures ranging from discrete clusters to two-dimensional layers, namely, [pipH2][pipH][AsS4] (1), [pipH2][pipH][As(Se0.4S0.6)4] (2), [pipH2]2[pipH]2[In2AsIII2AsV2S13.3(S2)0.7] (3), [pipH2]2[pipH]2[In2AsIII2AsV2S10.2Se3.1(Se2)0.7] (4), [pipH2]0.5[AsS(S2)] (5), [pipH2]0.5[AsS2] (6), [pipH]2[AgAsS4] (7), [pipH2]1.5[GaAsIIIAsVS7] (8), and Cs2[pipH]2[InAs6S12]Cl (9). Particularly, compounds 3, 4, and 8 contain mixed-valent AsIII and AsV ions in their discrete clusters and one-dimensional chain. In addition, compound 5 could thermodynamically transform to compound 6 with increasing reaction temperature, which may be attributed to the thermodynamically unstable S-S species in the chains of 5. The BA-EDT solvent mixture was crucial to the synthesis of these compounds, since no title crystals can be prepared by replacing the BA-EDT solvent mixture with other conventional solvents or removing one component of the BA-EDT solvent mixture from the reaction system. Our research demonstrates that thiol-amine solvent systems could be promising reaction media for growing novel crystalline chalcogenidometalates.

4.
Analyst ; 144(9): 3103-3110, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30920573

RESUMO

Receptor-targeted delivery systems have been proposed as means of concentrating therapeutic agents to improve therapeutic effects on disease sites and reduce side effects on normal issues. Herein, we synthesized biocompatible folic acid (FA)-functionalized DHE-modified TiP (TiP-PAH-DHE-FA) nanoparticles as a drug delivery system that possessed high drug loading capability and enhanced folate-receptor-mediated cellular uptake. Moreover, it also allowed drug effect evaluation based on the real-time monitoring of the fluorescence intensity of HE molecules that are triggered by intercellular ROS. This acquired drug delivery system provided a novel platform to integrate efficient cell-specific drug delivery with real-time monitoring of therapeutic efficacy.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Nanopartículas/química , Titânio/química , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Endocitose/fisiologia , Etídio/análogos & derivados , Etídio/química , Etídio/metabolismo , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Ácido Fólico/química , Ácido Fólico/metabolismo , Humanos , Células MCF-7 , Microscopia Confocal/métodos , Nanopartículas/metabolismo , Poliaminas/química , Poliaminas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Titânio/metabolismo
5.
Analyst ; 143(21): 5170-5175, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30259917

RESUMO

Facile and sensitive detection methods of cancer cells in the early stage are beneficial for monitoring cancers and treating patients in time to reduce the death rate. In this work, an ultrasensitive cytosensor was constructed using aptamers as cell capturers and metal ion-exchanged titanium phosphate nanospheres as electrochemical probes. KH1C12 can specifically recognize HL-60 cells and distinguish them from other cell lines, K562 and CCRF-CEM, to obtain high selectivity. Cadmium ion functionalized titanium phosphate nanospheres show large quantities of electroactive cadmium ion output and a highly sensitive electrochemical signal. This proposed cytosensor showed a wide dynamic linear range from 102 cells per mL to 107 cells per mL with a low detection limit of 35 cells per mL, providing a new, simple and ultrasensitive platform for cancer diagnosis in biomedical and clinical research.


Assuntos
Aptâmeros de Nucleotídeos/química , Nanosferas/química , Titânio/química , Técnicas Biossensoriais/métodos , Cádmio/química , Rastreamento de Células/métodos , Técnicas Eletroquímicas/métodos , Células HL-60 , Humanos , Limite de Detecção , Tamanho da Partícula , Sensibilidade e Especificidade
6.
Angew Chem Int Ed Engl ; 57(3): 678-682, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29205713

RESUMO

A new type of materials, organic salts in the crystal state, have ultralong organic phosphorescence (UOP) under ambient conditions. The change of cations (NH4+ , Na+ , or K+ ) in these phosphors gives access to tunable UOP colors ranging from sky blue to yellow green, along with ultralong emission lifetimes of over 504 ms. Single-crystal analysis reveals that unique ionic bonding can promote an ordered arrangement of organic salts in crystal state, which then can facilitate molecular aggregation for UOP generation. Additionally, reversible ultralong phosphorescence can be realized through the alternative employment of fuming gases (ammonia and hydrogen chloride), demonstrating its potential as a candidate for visual ammonic or hydrogen chloride gas sensing. The results provide an environmental responsible and practicable synthetic approach to expanding the scope of ultralong organic phosphorescent materials as well as their applications.

7.
Int J Neurosci ; 125(1): 66-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24670258

RESUMO

This study is to investigate the effects of etomidate and propofol on memory and possible involved mechanisms using immature rats. Forty-eight rats randomly received intraperitoneal injection of 5 mg/kg etomidate (n = 16), 50 mg/kg propofol (n = 16) or normal saline (control, n = 16). Three hours after awakening, memory was assessed by Y-maze test using 10 rats in each drug group. Gamma-aminobutyric acid (GABA) content in hippocampal tissue was measured using six rats in each group. Etomidate group had more total reaction time (TRT) compared with the control group in Y-maze test ( p < 0.05). No other difference between these two groups was observed. Propofol group had less number of correct response ( p < 0.01) and more TRT ( p < 0.05) in Y-maze test, as well as more GABA concentration detected in hippocampal tissue ( p < 0.01) than the control group. Propofol group also showed less number of correct response ( p < 0.05) and more hippocampal GABA concentration ( p < 0.01) compared with etomidate group. Etomidate does not show significant effects on memory in rat and further investigation is required. Propofol can affect memory in rat possibly via increasing the synthesis and/or secretion of GABA as one of the factors.


Assuntos
Anestésicos Intravenosos/farmacologia , Etomidato/farmacologia , Memória/efeitos dos fármacos , Propofol/farmacologia , Animais , Animais Recém-Nascidos , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo
8.
Angew Chem Int Ed Engl ; 54(40): 11616-23, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26266458

RESUMO

Given that surfactants can control the shape and size of micro-/nanoparticles, they should be able to direct the growth of bulk crystals. This Minireview summarizes recent developments in the application of surfactants for the preparation of new crystalline inorganic materials, including chalcogenides, metal-organic frameworks, and zeolite analogues. The roles of surfactants in different reaction systems are discussed.

9.
Angew Chem Int Ed Engl ; 54(2): 546-50, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25394683

RESUMO

Inserting polymers into a crystalline inorganic matrix to understand the structure, position, and the structure-property relationships of the resulting composites is important for designing new inorganic-organic materials and tuning their properties. Single crystals of polymer-chalcogenide composites were successfully prepared by trapping polyethyleneglycol within a selenidostannate matrix under surfactant-thermal conditions. This work might provide a new strategy for preparing novel crystalline polymer-inorganic composites through encapsulating polymer chains within inorganic matrices.

10.
Small ; 10(23): 4905-11, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25048818

RESUMO

Two new flexible visible-light photodetectors based on ZrS3 nanobelts films are fabricated on a polypropylene (PP) film and printing paper, respectively, by an adhesive-tape transfer method, and their light-induced electric properties are investigated in detail. The devices demonstrate a remarkable response to 405 to 780 nm light, a photocurrent that depends on the optical power and light wavelength, and an excellent photoswitching effect and stability. This implies that ZrS3 nanobelts are prospective candidates for high-performance nanoscale optoelectronic devices that may be practically applied in photodetection of visible to near infrared light. The facile fabrication method is extendable to flexible nanodevices with different nanostructures.

11.
J Org Chem ; 79(10): 4438-45, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24741990

RESUMO

Three novel diazatwistpentacenes (1,4,6,13-tetraphenyl-7:8,11:12-bisbenzo-2,3-diazatwistpentacene (1, IUPAC name: 9,11,14,16-tetraphenyl-1,6-dihydrobenzo[8,9]triphenyleno[2,3-g]phthalazine); 1,4-di(pyridin-2-yl)-6,13-diphenyl-7:8,11:12-bisbenzo-2,3-diazatwistpentacene (2, IUPAC name: 9,16-diphenyl-11,14-di(pyridin-2-yl)-1,6-dihydrobenzo[8,9]triphenyleno[2,3-g]phthalazine); and 1,4-di(thien-2-yl)-6,13-diphenyl-7:8,11:12-bisbenzo-2,3-diazatwistpentacene (3, IUPAC name: 9,16-diphenyl-11,14-di(thien-2-yl)-1,6-dihydrobenzo[8,9]triphenyleno[2,3-g]phthalazine)) have been successfully synthesized through [4 + 2] cycloaddition reaction involving in situ arynes as dienophiles and substituted 1,2,4,5-tetrazines as dienes. Their structures have been determined by single-crystal X-ray diffraction, confirming that all compounds have twisted configurations with torsion angles between the pyrene unit and the 2,3-diazaanthrance part as high as 21.52° (for 1), 24.74° (for 2), and 21.14° (for 3). The optical bandgaps for all compounds corroborate the values derived from CV. The calculation done by DFT shows that the HOMO-LUMO bandgaps are in good agreement with experimental data. Interestingly, the substituted groups (phenyl, pyridyl, thienyl) in the 1,4-positions did affect their self-assembly and the optical properties of as-resulted nanostructures. Under the same conditions, compounds 1-3 could self-assemble into different morphologies such as microrods (for 1), nanoprisms (for 2), and nanobelts (for 3). Moreover, the UV-vis absorption and emission spectra of as-prepared nanostructures were largely red-shifted, indicating J-type aggregation for all materials. Surprisingly, both 1 and 2 showed aggregation-induced emission (AIE) effect, while compound 3 showed aggregation-caused quenching (ACQ) effect. Our method to approach novel twisted azaacenes through [4 + 2] reaction could offer a new tool to develop unusual twisted conjugated materials for future optoelectronic applications.

12.
Inorg Chem ; 53(2): 691-3, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24372307

RESUMO

Six new zinc-1,3,5-benzenetricarboxylate-based metal-organic frameworks (MOFs) have been successfully synthesized using three different surfactants (PEG 400, octanoic acid, and hexadecyltributylphosphonium bromide) as reaction media. These surfactants with different characteristics, such as being neutral, acidic, and cationic, have been demonstrated to show strong effects on directing the crystals' growth and resulted in different secondary building units (SBUs) including an unusual SBU unit [Zn4(µ4-O)(CO2)7]. Our results clearly indicated that the surfactant-thermal method could offer exciting opportunities for preparing novel MOFs or other inorganic crystalline materials with diverse structures and interesting properties.

13.
Inorg Chem ; 53(19): 10248-56, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25208101

RESUMO

Although either surfactants or amines have been investigated to direct the crystal growth of metal chalcogenides, the synergic effect of organic amines and surfactants to control the crystal growth has not been explored. In this report, several organic bases (hydrazine monohydrate, ethylenediamine (en), 1,2-propanediamine (1,2-dap), and 1,3-propanediamine (1,3-dap)) have been employed as structure-directing agents (SDAs) to prepare four novel chalcogenides (Mn3Ge2S7(NH3)4 (1), [Mn(en)2(H2O)][Mn(en)2MnGe3Se9] (2), (1,2-dapH)2{[Mn(1,2-dap)2]Ge2Se7} (3), and (1,3-dapH)(puH)MnGeSe4(4) (pu = propyleneurea) under surfactant media (PEG-400). These as-prepared new crystalline materials provide diverse metal coordination geometries, including MnS3N tetrahedra, MnGe2Se7 trimer, and MnGe3Se10 T2 cluster. Compounds 1-3 have been fully characterized by single-crystal X-ray diffraction (XRD), powder XRD, UV-vis spectra, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Moreover, magnetic measurements for compound 1 showed an obvious antiferromagnetic transition at ~9 K. Our research not only enriches the structural chemistry of the transitional-metal/14/16 chalcogenides but also allows us to better understand the synergic effect of organic amines and surfactants on the crystallization of metal chalcogenides.

14.
Inorg Chem ; 53(16): 8529-37, 2014 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-25100615

RESUMO

In this report, three new metal-organic frameworks (MOFs), [Co3(µ3-OH)(HBTC)(BTC)2Co(HBTC)]·(HTEA)3·H2O (NTU-Z30), [Co(BTC)]·HTEA·H2O (NTU-Z31), [Co3(BTC)4]·(HTEA)4 (NTU-Z32), where H3BTC = 1,3,5-benzenetricarboxylic acid, TEA = triethylamine, and NTU = Nanyang Technological University, have been successfully synthesized under surfactant media and have been carefully characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis, and IR spectromtry. NTU-Z30 has an unusual trimeric [Co3(µ3-OH)(COO)7] secondary building unit (SBU), which is different from the well-known trimeric [Co3O(COO)6] SBU. The topology studies indicate that NTU-Z30 and NTU-Z32 possess two new topologies, 3,3,6,7-c net and 2,8-c net, respectively, while NTU-Z31 has a known topology rtl type (3,6-c net). Magnetic analyses show that all three materials have weak antiferromagnetic behavior. Furthermore, NTU-Z30 has been selected as the heterogeneous catalyst for the aerobic epoxidation of alkene, and our results show that this material exhibits excellent catalytic activity as well as good stability. Our success in growing new crystalline cobalt 1,3,5-benzenetricarboxylate MOFs under surfactant media could pave a new road to preparing new diverse crystalline inorganic materials through a surfactant-thermal method.


Assuntos
Cobalto/química , Compostos Organometálicos/química , Tensoativos/química , Ácidos Tricarboxílicos/química , Cristalografia por Raios X , Modelos Moleculares , Compostos Organometálicos/síntese química
15.
ACS Appl Mater Interfaces ; 16(27): 35024-35032, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38935758

RESUMO

Inorganic metal sulfides have received extensive investigation as anode materials in lithium-ion batteries (LIBs). However, applications of crystalline organic hybrid metal sulfides as anode materials in LIBs are quite rare. In addition, combining the nanoparticles of crystalline organic hybrid metal sulfides with conductive materials is expected to enhance the electrochemical lithium storage performance. Nevertheless, due to the difficulty of harvesting the nanoparticles of crystalline organic hybrid metal sulfides, this approach has never been tried to date. Herein, nanoparticles of a crystalline organic hybrid cadmium antimony sulfide (1,4-DABH2)Cd2Sb2S6 (DCAS) were prepared by a top-down method, including the procedures of solvothermal synthesis, ball milling, and ultrasonic pulverization. Thereafter, the nanoparticles of DCAS with sizes of ∼500 nm were intercalated into graphene oxide nanosheets through a freeze-drying treatment and a DCAS@GO composite was obtained. Compared with the reported Sb2S3- and CdS-based composites, the DCAS@GO composite exhibited superior electrochemical Li+ ion storage performance, including a high capacity of 1075.6 mAh g-1 at 100 mA g-1 and exceptional rate tolerances (646.8 mAh g-1 at 5000 mA g-1). In addition, DCAS@GO can provide a high capacity of 705.6 mAh g-1 after 500 cycles at 1000 mA g-1. Our research offers a viable approach for preparing the nanoparticles of crystalline organic hybrid metal sulfides and proves that intercalating organic hybrid metal sulfide nanoparticles into GO nanosheets can efficiently boost the electrochemical Li+ ion storage performance.

16.
J Am Chem Soc ; 135(4): 1256-9, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23311760

RESUMO

Although surfactants have been widely used to tailor the size, shape, and surface properties of nanocrystals and control the pore size and phases of mesoporous frameworks, the use of surfactants as reaction media to grow chalcogenide crystals is unprecedented. In addition, compared with ionic liquids, surfactants are much cheaper and can have multifunctional properties such as acidic, basic, neutral, cationic, anionic, or even block. These features suggest that surfactants could be promising reaction platforms for the development of novel chalcogenide crystals. In this work, we used chalcogenidoarsenates as a model system to demonstrate our strategy. By using three different surfactants as reaction media, we obtained a series of novel thioarsenates ranging from a zero-dimensional (0D) cluster to a three-dimensional (3D) framework, namely, [NH(4)](8)[Mn(2)As(4)S(16)] (1), [Mn(NH(3))(6)][Mn(2)As(2)S(8)(N(2)H(4))(2)] (2), [enH][Cu(3)As(2)S(5)] (3), and [NH(4)][MnAs(3)S(6)] (4). The band gaps (estimated from the steep absorption edges) were found to be 2.31 eV for 1 (0D), 2.46 eV for 2 (1D), 1.91 eV for 3 (2D), and 2.08 eV for 4 (3D). The magnetic study of 4 indicated weak antiferromagnetic behavior. Our strategy of growing crystalline materials in surfactants could offer exciting opportunities for preparing novel crystalline materials with diverse structures and interesting properties.


Assuntos
Arseniatos/química , Calcogênios/química , Tensoativos/química , Cristalização , Modelos Moleculares , Estrutura Molecular
17.
Inorg Chem ; 52(8): 4148-50, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23556509

RESUMO

Herein we report the surfactant-thermal method to prepare two novel one-dimensional mercury selenidostannates, [DBUH]2[Hg2Sn2Se6(Se2)] (1) and [DBUH]2[Hg2Sn2Se7] (2), where DBU = 1,8-diazabicyclo[5.4.0]undec-7-ene, by applying PEG-400 as the reaction medium. It is worth noting that 1 is kinetically stable and can be transformed into thermodynamically stable phase 2 under a longer reaction time. Our strategy "growing crystalline materials in surfactants" could open a new door to preparing novel crystals with diverse structures and interesting properties.

18.
Artigo em Inglês | MEDLINE | ID: mdl-36317753

RESUMO

Carbon-coated metal chalcogenide composites have been demonstrated as one type of promising anode material for sodium-ion batteries (SIBs). However, combining carbon materials with micronanoparticles of metal chalcogenide always involve complicated processes, such as polymer coating, carbonization, and sulfidation/selenization. To address this issue, herein, we reported a series of carbon-coated FexSey@CN (FexSey = FeSe2, Fe3Se4, Fe7Se8) composites prepared via the thermodynamic transformation of a crystalline organic hybrid iron selenide [Fe(phen)2](Se4) (phen = 1,10-phenanthroline). By pyrolyzing the bulk crystals of [Fe(phen)2](Se4) at different temperatures, FexSey microrods were formed in situ, where the nitrogen-doped carbon layers were coated on the surface of the microrods. Moreover, all the as-prepared FexSey@CN composites exhibited excellent sodium-ion storage capabilities as anode materials in SIBs. This work proves that crystalline organic hybrid metal chalcogenides can be used as a novel material system for the in situ formation of carbon-coated metal chalcogenide composites, which could have great potential in the application of electrochemical energy storage.

19.
Huan Jing Ke Xue ; 43(6): 3077-3087, 2022 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-35686777

RESUMO

Microplastics as a prevalent pollutant in water bodies have recently attracted widespread attention. To investigate the spatial and temporal distribution characteristics of microplastics in freshwater rivers and their migration patterns, the surface water, sediments, and subsidence zone of the Xiangxi River, a tributary of the Yangtze River, were sampled and analyzed in November 2020 and April 2021, respectively. The results showed that the average abundance of microplastics in the surface water of Xiangxi River was (6.64±1.32) n·L-1 in flat water and (5.00±1.07) n·L-1 in dry water, the average abundance of microplastics in sediments was (0.56±0.13) n·g-1 in flat water and (0.41±0.09) n·g-1 in dry water, and the average abundance of microplastics in the subsidence zone was (0.53±0.15) n·g-1 in flat water and (0.68±0.18) n·g-1in dry water. There were significant differences in the abundance distribution of microplastics in the surface water, sediments, and subsidence zone (P<0.05). In the surface water and sediments, the particle size of microplastics was mainly distributed in the range of 0.1-0.5 mm, and in the subsidence zone, it mainly ranged from 1-5 mm. The color of microplastics was mainly transparent in the surface water and subsidence zone and blue in sediments. The morphology of microplastics in the Xiangxi River basin was mainly fiber, and the materials were mainly polyethylene (PE) and polypropylene (PP). There were many factors affecting the distribution of microplastics. The analysis results showed that the abundance of microplastics in the surface water was negatively correlated with the flow rate of the water body. The abundance of microplastics in the sediment was related to the substrate type of the riverbed and negatively correlated with the substrate particle size. Combined with the microplastic abundance data of each sampling site, it was found that there was a significant migration process of microplastics in the spatial distribution of the Xiangxi River in the watershed. Along the river longitudinal direction, the longitudinal migration of microplastics in the surface water was along the river direction, and in the vertical direction, it showed the mutual migration between the water body and the subsidence zone and the water body and sediments.


Assuntos
Microplásticos , Rios , Água Doce , Plásticos , Água
20.
ACS Appl Mater Interfaces ; 13(46): 55188-55197, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34757713

RESUMO

Rare-earth elements (REEs) in industrial wastewaters have great value for recycling and reuse, but their characteristic of low concentration poses a challenge to an efficient enrichment from wastewaters. In recent years, thiometallates featuring two-dimensional layers have shown great potential in the enrichment of REEs via the ion-exchange process. However, investigations on thiometallates featuring three-dimensional anionic frameworks for the recovery of REEs have not been reported. Herein, K2Sn2S5 (KTS-2), a thiostannate possessing a three-dimensional porous framework, was chosen as an ion-exchange material for capturing REEs from an aqueous solution. Indeed, KTS-2 exhibited excellent ion-exchange performance for all 16 REEs (except Pm). Specifically, KTS-2 displayed a high capture capacity (232.7 ± 7.8 mg/g) and a short equilibrium time (within 10 min) for Yb3+ ions. In addition, KTS-2 had a high distribution coefficient for Yb3+ ions (Kd > 105 mL/g) in the presence of excessive interfering ions. Impressively, KTS-2 could reach removal rates of above 95% for all 16 REEs in a large quantity of wastewater with low initial concentration (∼7 mg/L). Moreover, KTS-2 could be used as an eco-friendly material for ion exchange of REEs, since the released K+ cations would not cause secondary pollution to the water solution.

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