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1.
J Colloid Interface Sci ; 671: 258-269, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38810340

RESUMO

The electrocatalytic nitrate reduction to ammonia reaction (ENO3RR) holds great potential as a cost-effective method for synthesizing ammonia. This work designed a cerium (Ce) doped Cu2+1O/Cu3VO4 catalyst. The coupling of vanadium-based oxides with Cu2+1O effectively adjusts the catalyst's electronic structure, addressing the inherent issues of limited activity and low conductivity in typical copper-based oxides; moreover, Ce doping generates oxygen vacancies (Ov), providing more active sites and thereby enhancing the ENO3RR performance. The catalyst exhibits superior NH3Faradaic efficiency (93.7 %) with a NH3 yield of 18.905 mg h-1 cm-2at -0.5 V vs. RHE under alkaline conditions. This study provides guidance for the design of highly efficient catalysts for ENO3RR.

2.
Mater Horiz ; 11(4): 978-987, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38112580

RESUMO

Smart and dynamic electromagnetic interference (EMI) shielding materials possess a remarkable capacity to modify their EMI shielding abilities, rendering them invaluable in various civil and military applications. However, the present response mechanism of switch-type EMI shielding materials is slightly restricted, as it primarily depends on continuous pressure induction, thereby resulting in concerns regarding their durability and reliability. Herein, for the first time, we demonstrate a novel method for achieving solvent-responsive, reversible switching, and robust EMI shielding capabilities using a controlled proton-reservoir ordered gel. The gel contains polyaniline (PANI) and sodium alginate (SA). Initially, SA acts as a proton reservoir for PANI in an aqueous system, enhancing the doping level of PANI and improving its electrical conductivity. Additionally, PANI and SA chains respond to diverse polar solvents, such as water, acetonitrile, ethanol, n-hexane, and air, inducing distinct conformations that affect the degree of PANI conjugation and electron migration along the chains. This process is reversible and non-destructive to the polymer chain, ensuring the effective and uncompromised performance of the EMI shielding switch. We can achieve precise and reversible tuning (on/off) of EMI shielding with different effectiveness levels by manipulating the solvents within the framework. This work opens a new solvent-stimuli avenue for the development of EMI shielding materials with reliable and intelligent on/off switching capabilities.

3.
Dalton Trans ; 52(46): 17470-17476, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37953713

RESUMO

The electrochemical nitrate reduction reaction (ENO3RR) is a green ammonia synthesis method under ambient conditions relative to the traditional Haber-Bosch technology, which does not require high-temperature or high-pressure conditions and can convert nitrate pollutants in the environment into value-added NH3, thus achieving a dual purpose. However, more electrocatalysts with a remarkable performance towards high-efficiency ENO3RR need to be developed. In this work, a Cu/NiO-NF composite electrocatalyst with a nanorod structure on nickel foam was successfully fabricated, which contains heterogeneous interfaces between Cu and NiO toward selective electrocatalytic nitrate reduction for ammonia synthesis. The steric nanorod morphology of the catalyst can significantly increase the surface area, expose more active sites, and improve the reaction activity. Moreover, the construction of the composite and the interface effectively boosts the synergistic effect of the active species Cu and NiO, which can regulate the electronic structure of the catalyst, expose more active sites, enhance the conductivity of the material, and accelerate the interfacial electron transfer, thereby further promoting the ENO3RR performance. This Cu/NiO-NF composite exhibits a high NH3 yield of 0.6 mmol h-1 cm-2 and up to 97.81% faradaic efficiency at the optimal applied potential of -1.0 V (vs. RHE) in a concentration of 0.1 M NO3--containing 0.1 M PBS. Furthermore, it demonstrates excellent electrochemical cycle stability. This work provides insights into the rational design and fabrication of ENO3RR electrocatalysts for potential electrocatalytic applications.

4.
Inorg Chem ; 62(33): 13338-13347, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37599583

RESUMO

Oxygen evolution reaction (OER) is a limiting reaction for highly efficient water electrolysis. Thus, the development of cost-effective and highly efficient OER catalysts is the key to large-scale water electrolysis for hydrogen production. Herein, by using an interfacial engineering strategy, a unique nanoflower-like Fe1-xNix(PO3)2/Ni2P/NF heterostructure with abundant heterogeneous interfaces is successfully fabricated. The catalyst exhibits excellent OER catalytic activity in alkaline fresh water and alkaline natural seawater at high current densities, which only, respectively, requires overpotentials of 318 and 367 mV to drive 1000 mA cm-2 in fresh water and natural seawater both containing 1 M KOH. Furthermore, Fe1-xNix(PO3)2/Ni2P/NF demonstrates excellent durability, which can basically remain stable for 80 h during the electrocatalytic OER processes, respectively, in alkaline fresh water and natural seawater. This work provides a new construction strategy for designing highly efficient electrocatalysts for OER at high current densities both in alkaline fresh water and in natural seawater.

5.
ACS Appl Mater Interfaces ; 15(27): 32803-32813, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37366118

RESUMO

Heterostructure engineering has emerged as a promising approach for creating high-performance microwave absorption materials in various applications such as advanced communications, portable devices, and military fields. However, achieving strong electromagnetic wave attenuation, good impedance matching, and low density in a single heterostructure remains a significant challenge. Herein, a unique structural design strategy that employs a hollow structure coupled with gradient hierarchical heterostructures to achieve high-performance microwave absorption is proposed. MoS2 nanosheets are uniformly grown onto the double-layered Ti3C2Tx MXene@rGO hollow microspheres through self-assembly and sacrificial template techniques. Notably, the gradient hierarchical heterostructures, comprising a MoS2 impedance matching layer, a reduced graphene oxide (rGO) lossy layer, and a Ti3C2Tx MXene reflective layer, have demonstrated significant improvements in impedance matching and attenuation capabilities. Additionally, the incorporation of a hollow structure can further improve microwave absorption while reducing the overall composite density. The distinctive gradient hollow heterostructures enable Ti3C2Tx@rGO@MoS2 hollow microspheres with exceptional microwave absorption properties. The reflection loss value reaches as strong as -54.2 dB at a thin thickness of 1.8 mm, and the effective absorption bandwidth covers the whole Ku-band, up to 6.04 GHz. This work provides an exquisite perspective on heterostructure engineering design for developing next-generation microwave absorbers.

6.
Inorg Chem ; 62(19): 7525-7532, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37133541

RESUMO

Electrocatalytic nitrate reduction reaction (ENO3RR) is an alternative, sustainable, and environmentally friendly value-added NH3 synthesis method under ambient conditions relative to the traditional Haber-Bosch process; however, its low NH3 yield, low Faradaic efficiency (FE), low selectivity, and low conversion rate severely restrict the development. In this work, a Cu2+1O/Ag-CC heterostructured electrocatalyst was successfully fabricated by constructing a heterogeneous interface between Cu2+1O and Ag for selective electrochemical nitrate-to-ammonia conversion. The construction of the heterogeneous interface effectively promotes the synergistic effect of the catalytically active components Cu2+1O and Ag, which enhances the material conductivity, accelerates the interfacial electron transfer, and exposes more active sites, thus improving the performance of ENO3RR. Such Cu2+1O/Ag-CC manifests a high NH3 yield of 2.2 mg h-1 cm-2 and a notable ammonia FE of 85.03% at the optimal applied potential of -0.74 V vs RHE in a relatively low concentration of 0.01 M NO3--containing 0.1 M KOH. Moreover, it shows excellent electrochemical stability during the cycle tests. Our study not only provides an efficient catalyst for ammonia electro-synthesis from ENO3RR but also an effective strategy for the construction of ENO3RR electrocatalysts for electrocatalytic applications.

7.
Small ; 19(36): e2302132, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37127874

RESUMO

Ultrathin 2D porous carbon-based materials offer numerous fascinating electrical, catalytic, and mechanical properties, which hold great promise in various applications. However, it remains a formidable challenge to fabricate these materials with tunable morphology and composition by a simple synthesis strategy. Here, a facile one-step self-flowering method without purification and harsh conditions is reported for large-scale fabrication of high-quality ultrathin (≈1.5 nm) N-doped porous carbon nanosheets (NPC) and their composites. It is demonstrated that the layered tannic/oxamide (TA/oxamide) hybrid is spontaneously blown, exfoliated, bloomed, in situ pore-formed, and aromatized during pyrolysis to form flower-like aggregated NPC. This universal one-step self-flowering system is compatible with various precursors to construct multiscale NPC-based composites (Ru@NPC, ZnO@NPC, MoS2 @NPC, Co@NPC, rGO@NPC, etc.). Notably, the programmable architecture enables NPC-based materials with excellent multifunctional performances, such as microwave absorption and hydrogen evolution. This work provides a facile, universal, scalable, and eco-friendly avenue to fabricate functional ultrathin porous carbon-based materials with programmability.

8.
Huan Jing Ke Xue ; 44(4): 2375-2383, 2023 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-37040986

RESUMO

Microplastics (MPs) are widely present in farmland soil as an emerging contaminant. This paper serves as a comprehensive and systematic review of research progress on the characteristics of distribution, abundance, sources, shape, polymer composition, size, and migration of MPs in farmland soils around the world. Moreover, research prospects were also proposed. MPs have been detected in farmland soils around the world, mainly coming from agricultural plastic films, organic fertilizers, sludge, surface runoff, agricultural irrigation, atmospheric deposition, and tire wear particles. The morphology of MPs in soil mainly includes debris, fibers, and films. MPs polymer forms mainly include polyethylene, polypropylene, and polystyrene. Farmland land use significantly affects soil MPs abundance. Additionally, the abundance of MPs increase with the reduction in size. MPs in soil can migrate to deep soil through tillage, leaching, bioturbation, and gravity. Research on soil MPs detection methods, database establishment, safety thresholds, migration and transformation laws, potential ecological health risk assessment, and the construction of prevention and control technology systems should be strengthened in the future. The paper can provide a reference for the risk control and governance of farmland soil MPs pollution.

9.
Inorg Chem ; 61(18): 7165-7172, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35465676

RESUMO

The electrocatalytic nitrogen reduction reaction (ECNRR) is a sustainable and environmentally friendly method for NH3 synthesis under environmental conditions relative to the Haber-Bosch process; however, its low selectivity (Faradaic efficiency (FE)) and low NH3 yield impede the progress. Herein, benefiting from the application of the interface engineering strategy, a multicomponent TiO2/Ag/Cu7S4@Se-CC heterogeneous electrocatalyst with a unique structure was successfully fabricated, generating a unique sandwich structure by using a Ag layer as an electric bridge intercalated between TiO2 and Cu7S4, in which the optimized catalyst can accelerate the electron transfer efficiency. Moreover, through the electronic structure adjustment, an electron-deficient region was constructed, which can inhibit the H2 adsorption but enhance the N2 adsorption, thereby improving the selectivity and the catalytic activity. Significantly, the FE and NH3 yield of TiO2/Ag/Cu7S4@Se-CC reached 51.05 ± 0.16% and 39.16 ± 2.31 µg h-1 cm-2, in which the FE is among the highest non-precious metal-based NRR electrocatalysts in alkaline electrolytes reported. This study provides insight into the rational design and construction of NRR electrocatalysts for electrocatalytic applications.

10.
Nanomicro Lett ; 14(1): 76, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35312846

RESUMO

Ingenious microstructure design and rational composition selection are effective approaches to realize high-performance microwave absorbers, and the advancement of biomimetic manufacturing provides a new strategy. In nature, urchins are the animals without eyes but can "see", because their special structure composed of regular spines and spherical photosensitive bodies "amplifies" the light-receiving ability. Herein, inspired by the above phenomenon, the biomimetic urchin-like Ti3C2Tx@ZnO hollow microspheres are rationally designed and fabricated, in which ZnO nanoarrays (length: ~ 2.3 µm, diameter: ~ 100 nm) as the urchin spines are evenly grafted onto the surface of the Ti3C2Tx hollow spheres (diameter: ~ 4.2 µm) as the urchin spherical photosensitive bodies. The construction of gradient impedance and hierarchical heterostructures enhance the attenuation of incident electromagnetic waves. And the EMW loss behavior is further revealed by limited integral simulation calculations, which fully highlights the advantages of the urchin-like architecture. As a result, the Ti3C2Tx@ZnO hollow spheres deliver a strong reflection loss of - 57.4 dB and broad effective absorption bandwidth of 6.56 GHz, superior to similar absorbents. This work provides a new biomimetic strategy for the design and manufacturing of advanced microwave absorbers.

11.
J Hazard Mater ; 417: 126086, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34020358

RESUMO

Although polycyclic aromatic hydrocarbons (PAHs) degradation under methanogenesis is an ideal approach to remediating PAH-polluted soil, the contribution of methanogenesis to soil PAH elimination and the relationships between microbial ecological characteristics and PAH degradation during this process remain unclear. Here, we conducted a short-term (60 days) incubation using a paddy soil amended with phenanthrene and examined the effects of a specific methanogenic inhibitor (2-bromoethanesulfonate, BES) on this process. As treatment assessments, the methane production activity (MPA), phenanthrene degradation rate (PDR), and microbial ecological characteristics were determined. The results indicated that BES significantly inhibited both soil MPA and PDR, and we detected a positive relationship between MPA and PDR. Furthermore, BES significantly altered the soil microbial community structure, and it was the microbial community structure but not α-diversity was significantly correlated with soil MPA and PDR. BES decentralized the co-occurrence of bacterial genera but intensified the co-occurrence of methanogens. Moreover, certain bacterial taxa, including Bacteroidetes-vadinHA17, Gemmatimonas, and Sporomusaceae, were responsible for the MPA and PDR in this paddy soil. Collectively, these findings confirm the role of methanogenesis in PAH elimination from paddy soil, and reveal the importance of microbial co-occurrence characteristics in the determination of soil MPA and pollutant metabolism.


Assuntos
Microbiota , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo , Microbiologia do Solo , Poluentes do Solo/análise
12.
Dalton Trans ; 50(15): 5236-5243, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33645597

RESUMO

A novel 3D Eu(iii) metal-organic framework (Eu-MOF-1) formulated as [Eu(L)(H2O)(DMA)] (L = 2-(2-nitro-4-carboxylphenyl)terephthalic acid) has been successfully synthesized under solvothermal conditions and characterized by structural analyses. Eu-MOF-1 displays a new 3D framework containing EuIII ions, ligand L, and coordinated DMA molecules and water molecules. The fluorescence investigations indicate that Eu-MOF-1 emits bright red luminescence, and shows relatively high water stability and outstanding chemical stability under a relatively wide range of pH conditions. It is noteworthy that Eu-MOF-1 can quantitatively detect p-aminophenol (PAP) which is a metabolite of phenylamine in human urine. More significantly, Eu-MOF-1 is the first reported multi-responsive luminescent sensor for detecting the biomarker PAP, and MnVII and CrVI anions with high selectivity, sensitivity, recyclability and relatively low detection limits in aqueous solutions. Furthermore, the possible sensing mechanisms of Eu-MOF-1 for selective sensing have also been explored in detail. Eu-MOF-1 could be an ideal candidate as a multi-responsive luminescent sensor in biological and environmental areas.


Assuntos
Aminofenóis/urina , Cromo/análise , Európio/química , Corantes Fluorescentes/química , Manganês/análise , Estruturas Metalorgânicas/química , Poluentes Químicos da Água/análise , Ânions/análise , Cristalografia por Raios X , Corantes Fluorescentes/síntese química , Humanos , Estruturas Metalorgânicas/síntese química , Modelos Moleculares , Solubilidade , Soluções , Água/química
13.
Dalton Trans ; 50(2): 553-561, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33350995

RESUMO

Three novel Cd(ii)/Zn(ii) coordination polymers (CPs), namely [Cd(L)(BPDC)0.5H2O]·0.5H2O (1), [Zn2(L)2(BPDC)]·2H2O (2) and [Cd2(L)(BTC)H2O]·3H2O (3) (L = 4-(tetrazol-5-yl)phenyl-4,2':6',4''-terpyridine, H2BPDC = 4,4'-biphenyldicarboxylic acid, and H3BTC = 1,3,5-benzenetricarboxylic acid), have been successfully synthesized and characterized. CP 1 and CP 2 display new two-dimensional double-layered honeycomb frameworks containing uncoordinated nitrogen atoms from pyridine and tetrazole rings, which can easily form hydrogen bonds with various analytes. CP 3 exhibits a 3D framework also with uncoordinated nitrogen atoms from pyridine and tetrazole rings. The fluorescence explorations indicate that CPs 1-3 exhibit strong blue luminescence and excellent chemical stability under a relatively wide range of pH conditions. It is worth noting that CPs 1-3 can quantitatively detect hippuric acid (HA), which is a metabolite of toluene in human urine, with high selectivity, sensitivity, fast response and relatively low detection limits. Moreover, the sensing mechanism of CPs 1-3 for HA can mainly be ascribed to fluorescence resonance energy transfer (FRET). CPs 1-3 could be ideal candidates as HA sensors in human urine samples for practical applications. Notably, to the best of our knowledge, we report for the first time Cd(ii)/Zn(ii)-based luminescent sensors for detecting HA in simulated urine.


Assuntos
Cádmio/química , Hipuratos/urina , Polímeros/química , Tolueno/toxicidade , Urinálise/métodos , Água/química , Zinco/química , Complexos de Coordenação/química , Humanos , Ligação de Hidrogênio , Limite de Detecção , Luminescência , Modelos Moleculares , Conformação Molecular , Fatores de Tempo
14.
Int J Clin Exp Pathol ; 13(2): 192-202, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32211099

RESUMO

BACKGROUND: Hepatorenal and hepatopulmonary syndrome are common clinical diseases; however, their mechanisms have not been fully elucidated. Our aim was to determine whether liver injury by bile duct ligation (BDL) causes modifications in kidney and lung tissue in mice, and to explore the possible mechanism of these changes. METHODS: BDL in mice was used as a research model. Pathologic changes of liver, kidney, and lung tissue were observed by hematoxylin-eosin (H&E) staining. The expression of IGFBPrP1, NF-κB, TNF-α, and IL-6 were investigated in liver, kidney, and lung tissue by immunohistochemical staining and western blot. The correlation between IGFBPrP1 and NF-κB, TNF-α, and IL-6 protein expression in liver, kidney, and lung tissues of each group was analyzed by the Pearson method. RESULTS: H&E staining showed, after BDL administration in mice, different degrees of inflammatory change in liver, kidney, and lung tissues of mice in each group. The results of immunohistochemical staining and western blot analysis showed increased expressions of IGFBPrP1, NF-κB, TNF-α, and IL-6 after BDL. Pearson correlation analysis showed that IGFBPrP1 positively correlated with the expressions of NF-κB, TNF-α, and IL-6. CONCLUSION: Liver injury caused by bile duct ligation can lead to kidney and lung tissue injury in mice. The mechanism of injury may be related to the high expression of liver injury factor IGFBPrP1, transcription factor NF-κB, proinflammatory cytokine TNF-α, and IL-6 in kidney and lung tissue. Moreover, an increased expression level of IGFBPrP1 may be accompanied by the activation of the NF-κB inflammatory pathway.

15.
Environ Sci Pollut Res Int ; 27(7): 7453-7462, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31884532

RESUMO

Soil methane generation mainly driven by soil prokaryotic microbes can be coupled with the degradation of petroleum hydrocarbons (PHCs); however, the relationship between prokaryotic community structure and methane production activity in soil with the potential risk of PHC contamination is seldom reported. In this study, 3 soil samples (CS-1 to CS-3) in the area nearby an exploratory gas well and 5 soil samples (DC-1 to DC-5) in a drill cutting dump area were obtained from the Fuling shale gas field (Chongqing City, China). Then, the prokaryotic community structure was examined by Illumina Miseq sequencing, and the linkage between soil methane production rate (MPR) and prokaryotic community composition was analyzed. The results indicated that 2 samples (DC-4 and DC-5) collected from the drill cutting dump area had significantly higher MPR than the other samples, and a significant and positive relationship (r = 0.44, P < 0.05) was found between soil MPR and soil organic matter (OM) content. The prokaryotic community composition in the sample (DC-5) with the highest MPR was different from those in the other samples, and soil OM and MPR were the major factors significantly correlated with the prokaryotic community structure in this soil. The samples (DC-4 and DC-5) with higher MPR had a higher relative abundance of Archaea and different archaeal community structures from the other samples, and the MPR was the sole factor significantly correlated with the archaeal genus composition in this soil. Therefore, both the prokaryotic and archaeal community structures are essential in the determination of soil MPR, and the bacterial genus of Saccharibacteria and the archaeal genus of Methanolobus might be the key contributors for methane generation in this soil from the shale gas field.


Assuntos
Metano/química , Campos de Petróleo e Gás , Solo , Archaea/crescimento & desenvolvimento , Archaea/metabolismo , China , Metano/metabolismo , Microbiologia do Solo
16.
Dalton Trans ; 47(27): 8972-8982, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29922782

RESUMO

Five new 3D isostructural lanthanide metal organic frameworks (Ln-MOFs), [Ln(HL)1.5(H2O)(DMF)]·2H2O (Ln = GdIII (1), SmIII (2), DyIII (3), EuIII (4) and TbIII (5), H3L = 5-(3',5'-dicarboxylphenyl) nicotinic acid) were synthesized by solvothermal methods and studied by structural analyses, magnetic analyses and luminescence sensing. Crystallographic studies revealed that these compounds are 3D frameworks in which the LnIII-COO chains with alternating four and two carboxylate bridges are interlinked by the organic ligands L, and contain microporous channels with accessible Lewis-base sites, coordinated water molecules and uncoordinated carboxyl groups, which are easy to combine and recognise various analytes. Magnetic studies demonstrated that the carboxylate bridges transmit interchain dominant ferromagnetic interactions in Gd-MOF (1) and Dy-MOF (3), while the decrease of the χT value in Sm-MOF (2) is due to the thermal depopulation effect of the excited levels. Furthermore, Dy-MOF (3) also shows slow magnetic relaxation behaviour under a zero dc field. The luminescence selective sensing experiments showed that Eu-MOF (4) and Tb-MOF (5) can act as recyclable sensors towards Fe3+ ions in water and the simulated biological fluids, and towards ketones in a water system with high sensitivity, selectivity and relatively low detection limits.

17.
J Neuroimmunol ; 317: 32-36, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29501083

RESUMO

BACKGROUND: Combined central and peripheral demyelination (CCPD) is rare and has never been reported as a spectrum disease in Han Chinese population. OBJECTIVES: To study the clinical features of CCPD in Han Chinese patients. METHODS: Twenty-two CCPD patients were selected from 788 demyelination cases. We reviewed and compared the clinical manifestation, laboratory data, electrophysiological examination, MRI and the prognosis. RESULTS: CCPD patients presented with sensory disturbance (86.4%), plegia (77.3%), cranial nerve involvement (77.3%), abnormal deep tendon reflexes (72.7%). CSF data showed increased CSF protein in 81% patients. Oligoclonal IgG bands (OB) were negative. Cortical or juxtacortical, periventricular, infratentorial lesions, thoracic and cervical spinal cord were mostly affected. Visual evoked potentials indicated optic nerves demyelinating in 50% cases. 21 CCPD patients were treated with intravenous immunoglobulin or steroids or both of them, and the efficacy was 33.3%, 54.5%, 71.4%, respectively. One case that showed no response to steroids plus intravenous immunoglobulin treatment was improved significantly after using cyclophosphamide. CONCLUSIONS: CCPD is a spectrum disease that can't be regarded as a simple combination of MS and CIDP. A suspected CCPD should receive brain and spinal MRI as well as electrophysiological examination to obtain a precise diagnosis.


Assuntos
Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/complicações , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/fisiopatologia , Polirradiculoneuropatia/complicações , Polirradiculoneuropatia/fisiopatologia , Adulto , Idoso , Povo Asiático , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polirradiculoneuropatia/imunologia , Estudos Retrospectivos , Adulto Jovem
18.
RSC Adv ; 8(39): 22046-22052, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35541715

RESUMO

A series of isomorphous three-dimensional metal-organic frameworks [CoII 1-x ZnII x (L)(N3)]·H2O (x = 0.26, 0.56 and 0.85) based on bimetallic CoII 1-x ZnII x (x = 0.26, 0.56 and 0.85) chains with random metal sites have been synthesized and magnetically characterized. The CoII 1-x ZnII x series, which intrinsically feature random anisotropic/diamagnetic sites, shows complex magnetic interactions. By gradually introducing the diamagnetic ZnII ions into the pure anisotropic CoII single-chain magnets system, the ferromagnetic interactions between CoII ions are gradually diluted. Moreover, the slow magnetic relaxation behaviour of the mixed metal CoII 1-x ZnII x systems also changes. In this bimetallic series CoII 1-x ZnII x , the Co-rich materials exhibit slow relaxation processes that may arise from SCM mechanism, while the ZnII-rich materials show significantly low slow magnetic relaxation. A general trend is that the activation energy and the blocking temperature decrease with the increase in diamagnetic ZnII content, emphasizing the importance of anisotropy for slow relaxation of magnetization.

19.
Chemistry ; 23(4): 896-904, 2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-27862438

RESUMO

A family of isomorphous three-dimensional metal-organic frameworks based on bimetallic (FeCo, FeNi, and CoNi) chains with random metal sites have been prepared and magnetically characterized. The solid-solution-type bimetallic materials inherit intrachain ferromagnetic interactions and single-chain-magnet (SCM) behaviors from the homometallic parent materials. Interestingly, different composition dependence of magnetic behaviors has been found. The FeII1-x NiIIx series (0≤x≤1) show an innocent composition dependence, where the blocking temperature of slow relaxation decreases monotonically as FeII is replaced by less anisotropic NiII . The FeII1-x CoIIx series show an unexpected antagonistic blending effect on slow relaxation: blending FeII and CoII tends to depress the spin dynamics, and the bimetallic materials with intermediate composition show significantly lower blocking temperature than both FeII and CoII materials. This is quite the opposite of what happens in the Co1-x Nix series, where CoII and NiII seem to have a synergetic effect so that slow relaxation in bimetallic systems can be promoted to higher temperature than both CoII and NiII materials.

20.
Int J Neurosci ; 126(12): 1103-11, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26643496

RESUMO

PURPOSE/AIM OF THE STUDY: We aimed to evaluate the association between serum uric acid (SUA) levels and cerebral white matter lesions (WMLs) in Chinese individuals. MATERIAL AND METHODS: We prospectively identified patients aged 50 years and older in neurology department from July 2014 to March 2015. Both periventricular WMLs (P-WMLs) and deep WMLs (D-WMLs) were identified on magnetic resonance imanging (MRI) scans and the severity was graded using the Fazekas method. Multivariate logistic regression analyses were performed to examine the association between SUA and WMLs. RESULTS: A total of 480 eligible participants were enrolled in this study. SUA level in severe group was much higher than that in mild group (for P-WMLs: 320.21 ± 79.97 vs. 286.29 ± 70.18, p = 0.000; for D-WMLs: 314.71 ± 74.74 vs. 290.07 ± 74.04, p = 0.031). Subgroup analyses showed that higher SUA level was associated with higher severity of P-WMLs in women, but not in male patients. Multivariate logistic regression analyses showed that SUA was still associated with increased risk of higher severity of P-WMLs (OR = 1.003, 95% = 1.000-1.006), but not D-WMLs. CONCLUSION: Elevated SUA level was independently associated with greater odds of higher severity of P-WMLs, particularly in women.


Assuntos
Córtex Cerebral/patologia , Leucoencefalopatias/sangue , Ácido Úrico/sangue , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Povo Asiático , Córtex Cerebral/diagnóstico por imagem , Colesterol/sangue , Feminino , Humanos , Leucoencefalopatias/diagnóstico por imagem , Lipoproteínas LDL/sangue , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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