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1.
J Hazard Mater ; 423(Pt A): 127104, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34523482

RESUMO

Soils contamination with Cd result in detriment to the environmental quality. In-situ immobilization methods by applying clay minerals have been gaining prominence. The effects on sepiolite of thermal activation at different temperatures (300-750 °C), for removing Cd from aqueous solutions were evaluated, in order to consider their further application for soil remediation. The influence of activation temperature was investigated using XRD, SEM, and N2 adsorption-desorption measurements. The S-600 exhibited the maximum adsorption capacity (21.28 mg/g), despite its lower SSA, and Langmuir model described the adsorption isotherms better than the Freundlich equation. TCLP was used to quantify the remediation effects of thermal-activated sepiolite on simulated soils artificially polluted with Cd. The results indicated that the mobility of Cd in soil was effectively reduced after treating with thermal-activated sepiolite and the use of S-600 was the most efficient, reducing the TCLP-Cd by approximately 73% compared with the control test. The main remediation mechanism was considered as the cation exchange of Cd by Mg at the edges of octahedral sheet. This study showed that thermal-activated sepiolite could be promising amendments for remediation of Cd-contaminated soil.

2.
Nature ; 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34587621

RESUMO

The transition-metal kagome lattice materials host frustrated, correlated, and topological quantum states of matter1-9. Recently, a new family of vanadium-based kagome metals AV3Sb5 (A=K, Rb, and Cs) with topological band structures has been discovered10,11. These layered compounds are nonmagnetic and undergo charge density wave transitions before developing superconductivity at low temperatures11-19. Here we report the observation of unconventional superconductivity and pair density wave (PDW) in CsV3Sb5 using scanning tunneling microscope/spectroscopy (STM/STS) and Josephson STS. We find that CsV3Sb5 exhibits a V-shaped pairing gap Δ~0.5 meV and is a strong-coupling superconductor (2∆/kBTc~5) that coexists with 4a0 unidirectional and 2a0×2a0 charge order. Remarkably, we discover a 3Q PDW accompanied by bidirectional 4a0/3 spatial modulations of the superconducting gap, coherence peak and gap-depth in the tunneling conductance. We term this novel quantum state a roton-PDW associated with an underlying vortex-antivortex lattice that can account for the observed conductance modulations. Probing the electronic states in the vortex halo in an applied magnetic field, in strong-field that suppresses superconductivity, and in zero-field above Tc reveals that the PDW is a primary state responsible for an emergent pseudogap and intertwined electronic order. Our findings show striking analogies and distinctions to the phenomenology of high-Tc cuprate superconductors, and provide groundwork for understanding the microscopic origin of correlated electronic states and superconductivity in vanadium-based kagome metals.

3.
Zhen Ci Yan Jiu ; 46(7): 562-9, 2021 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-34369675

RESUMO

OBJECTIVE: To investigate the effect of electroacupuncture (EA) on pain behaviors and expression of spinal dorsal horn melatonin receptor 2 (MT2) and interleukin-17 (IL-17) in neuropathic pain rats, so as to explore its mechanism underlying pain relief. METHODS: The present study includes 3 parts. In the first part, eighteen male SD rats were randomly divided into 3 groups: sham operation, model and EA groups, with 6 rats in each group. The neuropathic pain model was established by chronic constriction injury (CCI) of the right sciatic nerve. On the 7th day following modeling, EA was applied to the right "Zusanli" (ST36) and "Sanyinjiao" (SP6) (1 mA,2 Hz/100 Hz) for 30 min. The mechanical pain threshold(MWT) and thermal pain thre-shold(TPT) of the affected limb were detected before modeling, 7 days following modeling and 60 min after EA. The expression of MT2 in spinal dorsal horn was detected by Western blot. The contents of melatonin (Mel) and IL-17 in the spinal dorsal horn were determined by ELISA. The expression of glial fibrillary acidic protein (GFAP) in the spinal dorsal horn was determined by Western blot and immunohistochemistry. In the second part, 30 rats were divided into 5 groups: sham operation, model, EA, MT2 antagonist (4-P-PDOT), and dimethyl sulfoxide (DMSO) groups, with 6 rats in each group. Rats of the 4-P-PDOT and DMSO groups were intrathecal injection with 10 µL MT2 antagonist 4-P-PDOT (100 µg) and equivalent DMSO 30 min before EA. The MWT and TPT of affected limb were detected. The GFAP expression and IL-17 content in the spinal dorsal horn was detected by Western blot, immunohistochemistry and ELISA, respectively. In the third part, 30 rats were randomly divided into 5 groups: sham operation, model, EA, recombinant IL-17, and normal saline groups, with 6 rats in each group. The recombinant IL-17 protein (100 ng, 10 µL) and the same amount of 0.9% sodium chloride solution were intrathecal injection into the rats of the recombinant IL-17 group and the normal saline group 30 min before the EA. The MWT and TPT of affected limb were measured. RESULTS: On the 7th day after modeling, the MWT of rats in the model group and the EA group were significantly higher, while TPT were lower than those before the modeling (P<0.05). At 60 min after EA, compared with the model group, the MWT and TPT of the EA group reversed significantly (P<0.05). The levels of GFAP and IL-17 were significantly increased, while the levels of Mel and MT2 were significantly decreased in the model group than in the sham operation group (P<0.05), and those were considerably reversed in the EA group than in the model group (P<0.05). Compared with the EA and DMSO groups, the MWT in the 4-P-PDOT group were significantly increased, while TPT were decreased (P<0.05), and the contents of GFAP and IL-17 were significantly increased (P<0.05). Compared to the EA and normal saline groups, MWT of the rats in the recombinant IL-17 group were significantly increased, while TPT decreased (P<0.05). CONCLUSION: EA of ST36 and SP6 can alleviate neuropathic pain in CCI rats, which is closely related to its effect in inhibiting the release of IL-17 from astrocytes mediated by MT2.


Assuntos
Eletroacupuntura , Melatonina , Neuralgia , Animais , Astrócitos , Interleucina-17/genética , Masculino , Neuralgia/genética , Neuralgia/terapia , Ratos , Ratos Sprague-Dawley , Receptores de Melatonina , Medula Espinal , Corno Dorsal da Medula Espinal
4.
J Microbiol ; 59(8): 753-762, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34219208

RESUMO

The amylolytic yeast Saccharomycopsis fibuligera is a predominant species in starters and the early fermentation stage of Chinese liquor (Baijiu). However, the genetic diversity of the species remains largely unknown. Here we sequenced the genomes of 97 S. fibuligera strains from different Chinese Baijiu companies. The genetic diversity and population structure of the strains were analyzed based on 1,133 orthologous genes and the whole genome single nucleotide polymorphisms (SNPs). Four main lineages were recognized. One lineage contains 60 Chinese strains which are exclusively homozygous with relatively small genome sizes (18.55-18.72 Mb) and low sequence diversity. The strains clustered in the other three lineages are heterozygous with larger genomes (21.85-23.72 Mb) and higher sequence diversity. The genomes of the homozygous strains showed nearly 100% coverage with the genome of the reference strain KPH12 and the sub-genome A of the hybrid strain KJJ81 at the above 98% sequence identity level. The genomes of the heterozygous strains showed nearly 80% coverage with both the sub-genome A and the whole genome of KJJ81, suggesting that the Chinese heterozygous strains are also hybrids with nearly 20% genomes from an unidentified source. Eighty-three genes were found to show significant copy number variation between different lineages. However, remarkable lineage specific variations in glucoamylase and α-amylase activities and growth profiles in different carbon sources and under different environmental conditions were not observed, though strains exhibiting relatively high glucoamylase activity were mainly found from the homozygous lineage.

5.
Food Chem ; 362: 130257, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118510

RESUMO

The sensory features of white peony teas (WPTs) significantly change with storage age; however, their comprehensive associations with composition are still unclear. This study aimed to clarify the sensory quality-related chemical changes in WPTs during storage. Liquid chromatography-tandem mass spectrometry based on widely targeted metabolomics analysis was performed on WPTs of 1-13 years storage ages. Weighted gene co-expression network analysis (WGCNA) was used to correlate metabolites with sensory traits including color difference values and taste attributes. 323 sensory trait-related metabolites were obtained from six key modules via WGCNA, verified by multiple factor analysis. The decline and transformation of abundant flavonoids, tannins and amino acids were related to the reduced astringency, umami and increased browning of tea infusions. In contrast, the total contents of phenolic acids and organic acids increased with storage. This study provides a high-throughput method for the association of chemical compounds with various sensory traits of foods.


Assuntos
Metabolômica , Paeonia/química , Paladar , Chá/química , Aminoácidos/análise , Adstringentes/análise , Cromatografia Líquida , Flavonoides/análise , Manipulação de Alimentos/normas , Hidroxibenzoatos/análise , Espectrometria de Massas , Tempo
6.
J Org Chem ; 86(9): 6879-6887, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33905251

RESUMO

A novel method for the synthesis of N-difluoromethyl-2-pyridones was described. This protocol enables the synthesis of N-difluoromethyl-2-pyridones from readily available pyridines using mild reaction conditions that are compatible with a wide range of functional groups. The preliminary mechanistic study revealed that N-difluoromethylpyridinium salts were the key intermediates to complete this conversion.


Assuntos
Piridinas , Piridonas
7.
Org Lett ; 23(6): 2205-2211, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33635677

RESUMO

The reactivity of N-difluoromethylpyridinium salts is seldom explored because of their instability and low availability. Here we present a novel nucleophilic addition of N-difluoromethylpyridinium salts with nitroalkanes to synthesize N-CF2H-dihydropyridines and N-CHO-dihydropyridines in a highly efficient and regioselective pathway. This protocol exhibits good functional group tolerance and good to excellent yields.

8.
Org Lett ; 22(23): 9313-9318, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33197193

RESUMO

Here we present a novel annulation of pyridinium salts with BrCF2CO2Et to access the indolizine derivatives with high efficiency. The α substitution of pyridine plays a key role in determining the reaction pathways. Various types of indolizines can be conveniently accessed from easily available pyridinium salts under mild and simple reaction conditions.

9.
Org Lett ; 22(15): 6214-6219, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32683871

RESUMO

Tetrahydroxydiboron has previously been used as a borylation or reducing reagent in organic synthesis. Herein, we present a novel tetrahydroxydiboron-promoted radical addition of internal alkynes followed by intramolecular oxidation of alcohol through 1,5-hydrogen atom transfer. Preliminary mechanistic studies showed that the process might be initiated through N,N-dimethylformamide-assisted homolytic cleavage of tetrahydroxydiboron. This process provides a convenient synthesis of fluoroalkyl-substituted alkenes with a pendant aldehyde or ketone moiety.

10.
PLoS One ; 15(1): e0227137, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31999719

RESUMO

Across the world, certain schools struggle to recruit and retain qualified teachers. This study explores teacher mobility across schools in rural China. Using a dataset from the Gansu Survey of Children and Families, this study investigates how teacher's initial job placement relates to teacher mobility across schools. The findings show that non-local teachers whose initial placements were not in their hometowns were more likely to switch schools. Non-local teachers were also more likely to move for family reasons, compared to moving for personal development or due to involuntary transfer by the local government. The findings suggest that localized recruitment and deployment of teachers can be valuable for reducing teacher mobility rate and retaining teachers in hard-to-staff areas.


Assuntos
Emprego/estatística & dados numéricos , Migração Humana , Professores Escolares/estatística & dados numéricos , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Rural
11.
Int J Mol Sci ; 20(11)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185659

RESUMO

Ganoderic acids (GAs) are a type of highly oxygenated lanostane-type triterpenoids that are responsible for the pharmacological activities of Ganoderma lucidum. They have been investigated for their biological activities, including antibacterial, antiviral, antitumor, anti-HIV-1, antioxidation, and cholesterol reduction functions. Inducer supplementation is viewed as a promising technology for the production of GAs. This study found that supplementation with sodium acetate (4 mM) significantly increased the GAs content of fruiting bodies by 28.63% compared to the control. In order to explore the mechanism of ganoderic acid accumulation, the transcriptional responses of key GAs biosynthetic genes, including the acetyl coenzyme A synthase gene, and the expression levels of genes involved in calcineurin signaling and acetyl-CoA content have been analyzed. The results showed that the expression of three key GAs biosynthetic genes (hmgs, fps, and sqs) were significantly up-regulated. Analysis indicated that the acetate ion increased the expression of genes related to acetic acid assimilation and increased GAs biosynthesis, thereby resulting in the accumulation of GAs. Further investigation of the expression levels of genes involved in calcineurin signaling revealed that Na+ supplementation and the consequent exchange of Na+/Ca2+ induced GAs biosynthesis. Overall, this study indicates a feasible new approach of utilizing sodium acetate elicitation for the enhanced production of valuable GAs content in G. lucidum, and also provided the primary mechanism of GAs accumulation.


Assuntos
Carpóforos/metabolismo , Regulação Fúngica da Expressão Gênica , Reishi/metabolismo , Triterpenos/metabolismo , Acetato-CoA Ligase/genética , Acetato-CoA Ligase/metabolismo , Calcineurina/genética , Calcineurina/metabolismo , Cálcio/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reishi/genética , Sódio/metabolismo , Regulação para Cima
12.
Environ Sci Pollut Res Int ; 26(10): 9861-9875, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30734258

RESUMO

Montmorillonite grafted polyacrylic acid composite (GNM) was prepared by using ultraviolet radiation grafting method in this work. The synthesized materials were characterized by XRF, SEM, FTIR, XRD, TG, and XPS. The experimental equilibrium data indicates that the adsorbent is suitable for the Langmuir model and belongs to the pseudo-second-order kinetic model. The entire adsorption process is spontaneous, endothermic, and chaotically enhanced by thermodynamic analysis. The maximum adsorption capacity of La(III) by GNM was 280.54 mg/g at 313.15 K. In addition, the regeneration experiment shows that the adsorbent has good reusability and stable desorption efficiency. This study demonstrates that GNM has high adsorption performance and La(III) adsorption and regeneration capabilities to solve the water pollution caused by rare earth ions and regeneration capabilities for La(III).


Assuntos
Resinas Acrílicas/química , Bentonita/química , Lantânio/química , Poluentes Químicos da Água/química , Adsorção , Cinética , Termodinâmica , Raios Ultravioleta , Poluentes Químicos da Água/análise , Purificação da Água
13.
Org Lett ; 20(21): 6710-6714, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30354165

RESUMO

An efficient and facile method for the construction of tri- or tetrasubstituted exocyclic alkenes is achieved via a Cu(I)-catalytic system. This protocol exhibits mild conditions, low-cost catalyst, good functional group tolerance, and good yields. The selectivity toward tri- or tetrasubstituted alkenes can be delicately controlled by adjustment of base and solvent. A preliminary mechanism study manifested that the reaction undergoes a radical process, where B2pin2 plays an indispensable role.

14.
Environ Res ; 167: 276-282, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30077135

RESUMO

Malaria is an important vector-borne disease which is widespread in tropical and subtropical areas worldwide as well as in south China. Previous research has separately focused on the association between malaria incidence and meteorological variables or between malaria incidence and anti-malaria intervention measures in China, especially in Yunnan Province. Therefore, a typical county, Tengchong County, in Yunnan Province with high malaria incidence was selected as the study area to investigate the integrated influence of climate variance and anti-malaria intervention measures. Malaria incidence and meteorological variables were analyzed with a 2-month lag. The variables include average monthly temperature, minimum temperature, maximum temperature, cumulative precipitation, wind speed, maximum wind speed, relative humidity and minimum relative humidity. First, the principal component analysis was introduced to investigate the relationship between malaria incidence and meteorological variables; classification and regression trees were used to clarify contributions of key meteorological variables to malaria incidence afterwards. Second, based on existing anti-malaria intervention measures and above results, the integrated impact of climate variance and anti-malaria interventions on interannual trends of malaria incidence was analyzed. High malaria incidence occurred under one of the two meteorological conditions: 1) high minimum temperature combined with high minimum relative humidity or both precipitation and minimum relative humidity above middle level; 2) middle minimum temperature combined with both precipitation and minimum relative humidity below middle levels. Moreover, the steep interannual decline of malaria incidence in Tengchong was determined by slight climate variance and persistent anti-malaria intervention measures during malaria epidemics, predominantly by the latter. These findings will provide evidence data for developing malaria surveillance strategies in China.


Assuntos
Clima , Malária/epidemiologia , China/epidemiologia , Humanos , Umidade , Incidência , Malária/prevenção & controle , Temperatura
15.
Phys Rev Lett ; 120(15): 157205, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756861

RESUMO

We investigate a new class of topological antiferromagnetic (AF) Chern insulators driven by electronic interactions in two-dimensional systems without inversion symmetry. Despite the absence of a net magnetization, AF Chern insulators (AFCI) possess a nonzero Chern number C and exhibit the quantum anomalous Hall effect (QAHE). Their existence is guaranteed by the bifurcation of the boundary line of Weyl points between a quantum spin Hall insulator and a topologically trivial phase with the emergence of AF long-range order. As a concrete example, we study the phase structure of the honeycomb lattice Kane-Mele model as a function of the inversion-breaking ionic potential and the Hubbard interaction. We find an easy z axis C=1 AFCI phase and a spin-flop transition to a topologically trivial xy plane collinear antiferromagnet. We propose experimental realizations of the AFCI and QAHE in correlated electron materials and cold atom systems.

16.
Water Sci Technol ; 77(5-6): 1570-1580, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29595159

RESUMO

In the development of industrial life, an enormous amount of silica fume (SF) has been accumulated and cannot be reused properly, and a large quantity of rare-earth elements in industrial wastewater has been inappropriately discharged, both of which pose a threat to human health and the environment. By using UV photocatalytic grafting technology, a polymer brush grafted from modified SF, which can be used as a high efficiency adsorbent, can solve both problems at the same time. Specifically, SF was firstly silanol-functionalized by γ-methacryloxypropyltrimethoxysilane (KH570), then grafted with polyacrylic acid brushes by UV photocatalytic grafting to finally obtain the adsorbent. Under optimal conditions, adsorption capacity of the adsorbent for dysprosium(III) (Dy3+) could reach 278.49 mg/g. It took 1 min for the adsorbent to reach adsorbing equilibrium at a relatively low concentration of Dy3+ (40 mg/L), and only 3 min at a medium and high concentration (130 mg/L and 200 mg/L). After six adsorption-desorption cycles, the adsorbent still possessed high adsorption capacity for Dy3+ (251.20 mg/g). The adsorption behavior of the adsorbent fit the Langmuir isotherm model (R2 > 0.97) and pseudo-second-order kinetic model (R2 > 0.98) well. The functional group of carboxylate anion, -COO-, played a central role during the adsorption process, which was verified by Fourier transform infrared and X-ray photoelectron spectroscopy analyses.


Assuntos
Disprósio/química , Resíduos Industriais/análise , Dióxido de Silício/química , Águas Residuárias/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Purificação da Água/métodos
17.
China Q ; 230: 289-322, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29056815

RESUMO

It has been well established that better educated individuals enjoy better health and longevity. In theory, the educational gradients in health could be flattening if diminishing returns to improved average education levels and the influence of earlier population health interventions outweigh the gradient-steepening effects of new medical and health technologies. This paper documents how the gradients are evolving in China, a rapidly developing country, about which little is known on this topic. Based on recent mortality data and nationally representative health surveys, we find large and, in some cases, steepening educational gradients. We also find that the gradients vary by cohort, gender and region. Further, we find that the gradients can only partially be accounted for by economic factors. These patterns highlight the double disadvantage of those with low education, and suggest the importance of policy interventions that foster both aspects of human capital for them.

18.
Health Aff (Millwood) ; 36(9): 1672-1678, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28874497

RESUMO

Health insurance holds the promise of improving population health and survival and protecting people from catastrophic health spending. Yet evidence from lower- and middle-income countries on the impact of health insurance is limited. We investigated whether insurance expansion reduced adult mortality in rural China, taking advantage of differences across Chinese counties in the timing of the introduction of the New Cooperative Medical Scheme (NCMS). We assembled and analyzed newly collected data on NCMS implementation, linked to data from the Chinese Center for Disease Control and Prevention on cause-specific, age-standardized death rates and variables specific to county-year combinations for seventy-two counties in the period 2004-12. While mortality rates declined among rural residents during this period, we found little evidence that the expansion of health insurance through the NCMS contributed to this decline. However, our relatively large standard errors leave open the possibility that the NCMS had effects on mortality that we could not detect. Moreover, mortality benefits might arise only after many years of accumulated coverage.


Assuntos
Cobertura do Seguro/estatística & dados numéricos , Seguro Saúde/estatística & dados numéricos , Mortalidade/tendências , Serviços de Saúde Rural/tendências , Adulto , China , Humanos , População Rural
19.
Am J Trop Med Hyg ; 96(6): 1346-1349, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28719252

RESUMO

AbstractThe first human infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Shaanxi Province, China, in 2013, although the virus had been reported in 13 other provinces of China since 2010. We collected and analyzed a total of 4,011 samples, including 936 human serum samples, 155 animal serum samples, 895 ticks, 1,950 mosquitoes, 30 midges, and 20 sandflies. SFTSV antibodies were found in 44 human samples (4.7%) with no significant differences between males and females or across counties. The incidence rate of severe fever with thrombocytopenia syndrome was significantly higher among individuals 20-60 years of age. Moreover, SFTSV-specific antibodies were detected in goats (66.7%), cattle (13.2%), and dogs (15.0%), but not in pigs (0%). We detected the virus in Haemaphysalis concinna ticks with a prevalence rate of 21.3% (17/80 pools). All mosquito, midge, and sandfly samples were negative for SFTSV. These results support wide circulation of the virus in western China. Haemaphysalis concinna ticks may serve as a novel SFTSV vector, and the role of these ticks requires further investigation.


Assuntos
Animais Domésticos/virologia , Culicidae/virologia , Febre/epidemiologia , Ixodidae/virologia , Febre por Flebótomos/epidemiologia , Phlebovirus/isolamento & purificação , Adolescente , Adulto , Animais , Anticorpos Antivirais/sangue , Bovinos , Criança , China/epidemiologia , Cães , Feminino , Febre/virologia , Cabras , Humanos , Incidência , Insetos Vetores/virologia , Masculino , Pessoa de Meia-Idade , Febre por Flebótomos/virologia , Fatores Socioeconômicos , Suínos , Adulto Jovem
20.
Water Sci Technol ; 75(12): 2755-2764, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28659515

RESUMO

The recovery of rare earth ions from industrial wastewater has aroused wide concern in recent years. In present work, we synthesized a novel three-dimensional adsorbent (denoted as LF-AA) by grafting loofah fiber with acrylic acid via ultraviolet radiation. The LF-AA was washed by boiling water and subjected to soxhlet extraction with acetone and then fully characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscopy (SEM). Rare earth ion (Ce(III)) was selected as a model to validate its adsorption property. The saturation adsorption capacity for Ce(III) reaches 527.5 mg/g. Not only was this material highly efficient at adsorbing Ce(III) from aqueous solutions, it also proved to have ideal performance in regeneration; the total adsorption capacity of LF-AA for Ce(III) after six successive cycles decreased only 6.40% compared with the initial capacity of LF-AA. More importantly, the LF-AA can be easily separated from aqueous solutions because of its three-dimensional sponge natural structure. This study provides a new insight into the fabrication of biomass adsorbent and demonstrated that the LF-AA can be used as excellent adsorbent for the recovery of rare earth ions from wastewater.


Assuntos
Cério/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Poluentes Químicos da Água/análise , Adsorção , Biomassa , Cério/química , Concentração de Íons de Hidrogênio , Cinética , Polimerização , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta , Poluentes Químicos da Água/química
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