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1.
Sci Total Environ ; 806(Pt 3): 150652, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34610397

RESUMO

By the facile immobilization of ethylenediamine tetramethylene-phosphonic acid (EDTMPA) onto the surface and into the defects of UiO-66, a stable and efficient adsorbent named UiO-66-EDTMPA was obtained for the first time. In terms of removing aqueous heavy metal ions (Pb2+, Cd2+, Cu2+), the maximum adsorption capacities of UiO-66-EDTMPA reached 558.67, 271.34 and 210.89 mg/g, which were 8.77 (Pb2+), 5.63 (Cd2+) and 5.19 (Cu2+) times higher than raw UiO-66 respectively. The adsorption behavior of three heavy metal ions on UiO-66 and UiO-66-EDTMPA were investigated and compared through batch control experiments and theoretical studies. The main factors on adsorption progress (i.e., the dosage of EDTMPA, pH, ionic strength, co-existing ions, initial concentration, contact time, temperature) were explored, and the critical characterization (i.e., SEM, TEM, XRD, FT-IR, TG-DTG, XPS, N2 adsorption-desorption test) were performed. Molecular dynamics (MD) simulation (radial distribution functions (RDF) and mean square displacement (MSD)) were also applied to reveal the adsorption behavior. Besides, two new quantum chemical analyses (Hirshfeld surface and independent gradient model (IGM)) were introduced into the interaction analysis between UiO-66 and EDTMPA. The complete results showed that (1) where the hydrogen bond and (vdW) connect EDTMPA to UiO-66. (2) The coordination between O, N atoms of EDTMPA and heavy metal ions (Pb2+, Cd2+, Cu2+) resulted in spontaneous adsorption. (3) The adsorption behavior agreed with Langmuir and pseudo-second-order model, endothermic reaction. In addition, the desorption and reusability study showed promising stable and sustainable performance. This work has some guiding significance for the experimental and theoretical study of removing heavy metal ions from aqueous solutions by MOF or modified MOF materials.

2.
J Colloid Interface Sci ; 608(Pt 1): 322-333, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34628312

RESUMO

Effective removal of antibiotics in the environment can be a demanding issue concerning the ecosystem and human health. Photocatalysis and peroxymonosulfate (PMS) oxidation have become important methods to effectively remove stubborn pollutants. In this work, by integrating these two technologies, an efficient system for degrading chloramphenicol (CAP) in water was proposed. The system was constructed by coupling strontium-doped lanthanum cobaltate (LSCO5) with chlorine-doped carbon nitride (CGCN). By doping, the increase of oxygen vacancy and the adjustment of bandgap were realized. Photoluminescence and electrochemical impedance experiments showed that the heterojunction can promote electron transfer and photogenerated carrier separation. Under the synergistic effect of PMS oxidation and photocatalysis, the prepared composite with an optimal loading of 40% LSCO5 can degrade 95.6% of CAP within 20 min. Degradation experiments on different pollutants proved the versatility of the catalytic system. The enhanced degradation mechanism of CAP was explored based on the assessment of the degradation efficiency of CAP, electron paramagnetic resonance (EPR), and quenching experiments. Through liquid chromatography-mass spectrometry (LC-MS) analysis, a possible route for CAP degradation was also proposed. This research provides some inspiration for the remediation of polluted water with perovskite-based catalyst under the synergistic effect of PMS and photocatalysis.

3.
Langmuir ; 37(28): 8426-8434, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34233119

RESUMO

CuCo2O4, a type of promising lithium-ion storage material, exhibits high electrochemical properties in lithium-ion batteries and enormous economic benefits. However, its practical application is limited by problems such as structural collapse and electrochemical stability during the charging and discharging process. In this work, the reduced graphene oxide (rGO)-coated CuCo2O4 (CuCo2O4/rGO) hollow microspheres were successfully prepared by electrostatic self-assembly. The CuCo2O4/rGO electrode shows an outstanding capability for lithium-ion storage and a remarkable rate capacity, e.g., 445 mA h g-1 at 5 A g-1. After 150 cycles at 0.1 A g-1, the reversible capacity of the CuCo2O4/rGO electrode is as high as 1080 mA h g-1, and it can still retain about 530 mA h g-1 in the 400th cycle at 1 A g-1. The hollow microspheres with mesoporous shells can cause electrolyte penetration into the spherical shell to effectively shorten the transfer distance of lithium ions, and the encapsulation of graphene improves the conductivity and stability of CuCo2O4, which endows CuCo2O4/rGO with a wonderful Li+ storage performance. It is proved that this is an efficient method to improve the electrochemical performance of metal compounds for better applications in energy storage.

4.
Biosens Bioelectron ; 189: 113373, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34090152

RESUMO

Aflatoxin B1 (AFB1) is the most toxic mycotoxin, is widely found in foods and animal feeds, and can pose a serious threat to our lives. A label-free photoelectrochemical (PEC) immunosensor was fabricated for the sensitive detection of AFB1. A Z-scheme heterojunction of gold nanoparticles (Au NPs) loaded on graphitic carbon nitride sheet and tungsten trioxide sphere composite (g-C3N4/Au/WO3) acted as the highly sensitive platform. The g-C3N4/Au/WO3 is capable, not only of immobilizing antibodies via Au NPs, but also enhancing the separation of electron-hole pairs due to its good energy band matching efficiency. The mechanism of photo-generated electron/hole transfer on g-C3N4/Au/WO3 was explored using scavengers to eliminate active components. On this basis, an electron transfer pathway for the immunosensor was deduced. The PEC immunosensor displayed a linear concentration range from 1.0 pg mL-1 to 100 ng mL-1 and a low detection limit of 0.33 pg mL-1 (S/N = 3) for AFB1. Good reproducibility, stability, and specificity provide a solid foundation for the practical application of this immunosensor.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Aflatoxina B1 , Animais , Técnicas Eletroquímicas , Ouro , Imunoensaio , Limite de Detecção , Reprodutibilidade dos Testes
5.
Scanning ; 2021: 6650020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936356

RESUMO

Air pollution has become a matter of close concern to people with the continuous development of human society. However, the knowledge of air pollution mechanisms remains insufficient, and there is a lack of evaluation methods for actual pollution. In this paper, air pollution in Internet cafe was studied by detecting surface topography of glass slides after different exposure time by an atomic force microscope (AFM). It is found that the adsorption of air pollutants on glass surface undergoes initial aggregation, particle growth and interparticle deposition, and final full coverage. The chemical composition of contaminated glass surface was further analyzed by an X-ray photoelectron spectrometer, showing that the pollution was mainly composed of hydrocarbons regardless of exposure time. Cleaning experiments show that NaHCO3 solution can be the most effective one with saponification reaction and hydrolysis to remove the adsorbed contaminations. This study provides an alternative way for investigating air pollution and a reference for cleaning polluted material surfaces.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Adsorção , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Vidro , Humanos , Microscopia de Força Atômica
6.
ACS Appl Mater Interfaces ; 13(21): 24785-24794, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34013732

RESUMO

A three-dimensional (3D) printing method has been developed for preparing a lithium anode base on 3D-structured copper mesh current collectors. Through in situ observations and computer simulations, the deposition behavior and mechanism of lithium ions in the 3D copper mesh current collector are clarified. Benefiting from the characteristics that the large pores can transport electrolyte and provide space for dendrite growth, and the small holes guide the deposition of dendrites, the 3D Cu mesh anode exhibits excellent deposition and stripping capability (50 mAh cm-2), high-rate capability (50 mA cm-2), and a long-term stable cycle (1000 h). A full lithium battery with a LiFePO4 cathode based on this anode exhibits a good cycle life. Moreover, a 3D fully printed lithium-sulfur battery with a 3D printed high-load sulfur cathode can easily charge mobile phones and light up 51 LED indicators, which indicates the great potential for the practicability of lithium-metal batteries with the characteristic of high energy densities. Most importantly, this unique and simple strategy is also able to solve the dendrite problem of other secondary metal batteries. Furthermore, this method has great potential in the continuous mass production of electrodes.

7.
Int. braz. j. urol ; 47(1): 8-19, Jan.-Feb. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1134333

RESUMO

ABSTRACT Objective: Recently, several studies have found that obesity had a protective effect against varicocele, but no meta-analysis has confirmed this finding. Therefore, we conducted this meta-analysis to investigate the association between body mass index (BMI) and varicocele. Material and Methods: We searched for studies in PubMed, Science Direct and the Cochrane Library from inception until February 2018. The association between BMI and varicocele was assessed by pooling the odds ratios (ORs). Results: Eleven eligible studies with a total study population of 1.376.658 participants were included in our analysis. According to BMI, the subjects were defined as belonging to the obese, overweight and underweight groups. Our results showed that the obese group had a lower risk of varicocele when compared with the normal weight group (odds ratio [OR] 0.46, 95% confidence intervals [CIs] 0.37-0.58). Additionally, an overweight BMI had a protective effect against varicocele (OR 0.70, 95% CIs, 0.56-0.86). However, underweight patients had a more than 30% higher risk of varicocele (OR 1.31, 95% CI, 1.04-1.64). Furthermore, there was no publication bias in any of the analyses. Conclusions: Our study demonstrates that BMI is negatively associated with the presence of varicocele.


Assuntos
Humanos , Masculino , Varicocele/epidemiologia , Índice de Massa Corporal , Razão de Chances , Sobrepeso/complicações , Sobrepeso/epidemiologia , Obesidade/complicações
8.
Chemistry ; 27(15): 4869-4875, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33448047

RESUMO

The surface hydroxyl groups of Nix Cu1-x (OH)2 play a crucial role in governing their conversion efficiency into Nix Cu1-x Ox (OH)2-x during the electro-chemical pre-activation process, thus affecting the integral ammonia oxidation reaction (AOR) reactivity. Herein, the rational design of hierarchical porous NiCu double hydroxide nanotyres (NiCu DHTs) was reported for the first time by considering hydroxyl-rich interfaces to promote pre-activation efficiency and intrinsic structural superiority (i.e., annulus, porosity) to accelerate AOR kinetics. A systematic investigation of the structure-function relationship was conducted by manipulating a series of NiCu DHs with tunable intercalations and morphologies. Remarkably, the NiCu DHTs exhibit superior AOR activity (onset potential of 1.31 V with 7.52 mA cm-2 at 1.5 V) and high ammonia sensitivity (detection limit of 9 µm), manifesting one of the best non-noble metal AOR electrocatalysts and electro-analytical electrodetectors. This work deepens the understanding of the crucial role of surface hydroxyl groups on determining the catalytic performance in alkaline medium.

9.
Environ Technol ; 42(13): 2077-2084, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31701807

RESUMO

In this article, the spherical filler-like ZnFe2O4/Bi2MoO6 (ZFO/BMO) surrounded by nanosheets were synthesized by a solvothermal method using spherical ZnFe2O4 as a matrix. Scanning electron microscope (SEM), X-ray diffraction (XRD), Photoluminescence (PL), Fourier transform infrared spectroscopy (FT-IR) and Diffuse reflectance spectra (DRS) were used to characterize the prepared samples. The photocatalytic performance of the material was detected under 420 nm visible light by Rhodamine B (RhB). The degradation results indicated that the ZFO/BMO photocatalyst with 20% ZnFe2O4 content (ZFO/BMO-2) demonstrated highly efficient performance. The constructed Z-type ZFO/BMO heterojunction lengthens the visible light absorption threshold and improves the photocatalytic activity. Furthermore, ZFO/BMO heterojunction composite photocatalyst can be recycled effectively by applying an appropriate external magnetic field. It has important research value in photocatalysis and recycling.


Assuntos
Bismuto , Molibdênio , Catálise , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Luminescence ; 36(1): 200-209, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32805085

RESUMO

Photoluminescent (PL) carbon quantum dots (CQDs) were prepared successfully using a facile and green procedure. They exhibited striking blue fluorescence and excellent optical properties, with a quantum yield as high as 61.44%. Due to the fluorescence quenching effect and the stronger complexing ability of the phosphoric acid group of 1-hydroxyethane-1,1-diphosphonic acid (HEDP) to Fe3+ , CQDs doped with Fe3+ were adequately constructed as an efficient and sensitive fluorescent probe for HEDP-specific sensing. The proposed fluorescent probe had a sensitive and rapid response in the range 5-70 µM. Furthermore, quantitative molecular surface (QMS) analysis based on the Multiwfn program was applied to explore the complexation mode of HEDP and metal ions. The distribution of electrostatic potential (ESP), average local ionization energy (ALIE), the minimum value points and the position of the lone pair electrons on the surface of molecular van der Waals were further determined. More strikingly, this experiment achieved the quantitative detection of water-soluble phosphonate-HEDP, for the first time using fluorescence spectrometry. It has been proved to be an effective and intuitive sensing method for the detection of HEDP in real samples.


Assuntos
Organofosfonatos , Pontos Quânticos , Carbono , Espectrometria de Fluorescência , Água
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 246: 119004, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33070014

RESUMO

A novel ratiometric fluorescent sensor based on Förster resonance energy transfer (FRET) platform was designed for riboflavin (RF) detection. The graphitic carbon nitrides quantum dots - Zn-MOF composite (g-CNQDs@Zn-MOF) was used as the fluorescent probe. In the FRET system, g-CNQDs@Zn-MOF and RF acted as donor and acceptor, respectively. The probe exhibited high sensitivity and good selectivity to RF, and had been successfully used for the detection of RF in milk and vitamin B2 tablets. The detection limit of the sensor was 15 nM. The strategy expanded the application of MOF in sensing filed and provided a new method for the detection of RF.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Pontos Quânticos , Riboflavina/análise , Corantes Fluorescentes , Zinco
12.
Bioorg Med Chem ; 30: 115954, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33360197

RESUMO

Acute respiratory distress syndrome/chronic obstructive pulmonary disease (ARDS/COPD) is a diffuse inflammatory injury of the lung that is characterized by respiratory distress and vascular leakage and is caused by various factors. Although the treatment strategy for ARDS/COPD continues to be improved, it still lacks effective drugs. MCC950 is a potent and selective inhibitor ofthe nucleotide-binding oligomerization domain-like-receptor family pyrin domain-containing 3 (NLRP3) inflammasome. However, there have been no reports on the effects of MCC950 on lipopolysaccharide (LPS)-induced lung inflammation in mice. The objective of the present study was to evaluate the effects of MCC950 (given either intranasally or intraperitoneally) on inhibiting LPS-induced lung inflammation in mice. Acute lung inflammation was induced by intratracheal administration of LPS in ICR mice. The results showed that MCC950 at 50 mg/kg efficiently suppressed neutrophil lymphocytes (p < 0.001) and macrophage accumulation (p < 0.01) in bronchoalveolar lavage fluid (BALF) in LPS-instilled mice. In addition, hematoxylin and eosin (H&E) staining revealed that MCC950 at 50 mg/kg significantly inhibited pathological progress in the lung tissues (p < 0.01). Furthermore, treatment with MCC950 substantially reduced mRNA expression of IL-1ß, IL-8, TGF-ß1, and MMP-9 and also reduced protein levels of IL-1ß, IL-18 and caspase-1 at 24 h after LPS instillation. The results of the present study indicate that MCC950 effectively inhibits LPS-induced lung inflammation in vivo, which can be considered for clinical translation.


Assuntos
Furanos/farmacologia , Indenos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Pneumonia/tratamento farmacológico , Sulfonamidas/farmacologia , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Infiltração de Neutrófilos/efeitos dos fármacos , Pneumonia/induzido quimicamente , Pneumonia/metabolismo , Relação Estrutura-Atividade
13.
Int Braz J Urol ; 47(1): 8-19, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32271509

RESUMO

OBJECTIVE: Recently, several studies have found that obesity had a protective effect against varicocele, but no meta-analysis has confirmed this finding. Therefore, we conducted this meta-analysis to investigate the association between body mass index (BMI) and varicocele. MATERIAL AND METHODS: We searched for studies in PubMed, Science Direct and the Cochrane Library from inception until February 2018. The association between BMI and varicocele was assessed by pooling the odds ratios (ORs). RESULTS: Eleven eligible studies with a total study population of 1.376.658 participants were included in our analysis. According to BMI, the subjects were defined as belonging to the obese, overweight and underweight groups. Our results showed that the obese group had a lower risk of varicocele when compared with the normal weight group (odds ratio [OR] 0.46, 95% confidence intervals [CIs] 0.37-0.58). Additionally, an overweight BMI had a protective effect against varicocele (OR 0.70, 95% CIs, 0.56-0.86). However, underweight patients had a more than 30% higher risk of varicocele (OR 1.31, 95% CI, 1.04-1.64). Furthermore, there was no publication bias in any of the analyses. CONCLUSIONS: Our study demonstrates that BMI is negatively associated with the presence of varicocele.


Assuntos
Varicocele , Índice de Massa Corporal , Humanos , Masculino , Obesidade/complicações , Razão de Chances , Sobrepeso/complicações , Sobrepeso/epidemiologia , Varicocele/epidemiologia
14.
ACS Appl Mater Interfaces ; 13(1): 660-670, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33375778

RESUMO

CoSnO3, as a high theoretical capacity electrode material (1235 mAh g-1) for lithium storage, has been limited due to its low rate performance, huge volume expansion, and an unstable solid electrolyte interface (SEI). A rational design of the material structure including carbon coating can effectively solve the problems. To buffer the volume change and achieve a superior rate capability, hollow CoSnOx nanocubes encapsulated in 1D N-doped carbon nanofibers (CNFs) were fabricated by electrospinning, showing a final discharge capacity of 733 mAh g-1 with a 96% capacity retention after 800 cycles at a current rate of 1 A g-1 and a brilliant rate performance (49% capacity maintenance with the current variation from 0.1 to 5 A g-1). Absolutely, these outstanding characteristics are ascribed to the unique structure. The N-doped carbon fibers outside not only prevent the volume expansion during Li+ intercalation/extraction but also improve the electron transport in the electrode. Most significantly, the hollow structure offers enough vacant space to buffer the internal strain, while the porous structure shortens the Li+ diffusion distance. Combined with electrospinning technology, this study shares a novel idea for designing various composites with rational structures and outstanding electrochemical properties.

15.
Carbon Balance Manag ; 15(1): 7, 2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32361855

RESUMO

BACKGROUND: Intensification of agricultural systems may result in overexploitation of water resources in arid regions because enhanced productivity of crops is often associated with increased actual evapotranspiration (AET). The aim of this study was to quantify the effect of increased regional AET on the groundwater level in a case study of the oasis located within the Shiyang River Basin near the edge of the Gobi Desert. RESULT: The results of the study show that regional AET increased during the period from 1981 to 2010 due to increasing oasis area and air temperature. The water losses due to AET exceeded the water supply from the mountainous discharges of the basin by the end of this period, leading to groundwater overexploitation in the oasis area. CONCLUSIONS: This case study shows the importance of considering the effect of climate change on water losses associated with increasing agricultural production for the sustainable agricultural development of arid regions.

16.
Ultrason Sonochem ; 67: 105164, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32417625

RESUMO

In modern approaches for nanomaterials synthesis, ultrasonication plays an important role in providing the larger surface area and smaller crystalline size properties that are favorable to electrochemical techniques. Herein, we report the tin (IV) oxide on graphene oxide nanoparticles were synthesized (SnO2@GO NPs) by ultrasonic methodology (UZ SONOPULS HD 3400 Ultrasonic homogenizer) with the total power of 400 W and the (frequency of 20 kHz; 140 W/dm3). The formation of as-prepared SnO2@GO NPs and its surface morphology were scrutinized over XRD, XPS, TEM, and FESEM. Besides, the sonochemically prepared SnO2@GO NPs were employed for the determination of environmental hazardous mercury (Hg). As a result, the modified electrode acquired a very low-level detection limit of 1.2 nM with a wider range of 0.01-10.41-µM and 14.52-225.4-µM for the detection of Hg. Finally, the practical applicability of SnO2@GO NPs in spiked human blood serum and tuna fish samples shows appreciable found and recovery values. .


Assuntos
Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Grafite/química , Mercúrio/análise , Sonicação , Compostos de Estanho/química
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 231: 118131, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062514

RESUMO

A novel method for turn-off sensing 1,1-diamino-2,2-dinitroethylene (FOX-7) in aqueous medium was first proposed based on the inner filter effect (IFE) of FOX-7 on the fluorescence of molybdenum disulfide quantum dots (MoS2 QDs). Water-soluble MoS2 QDs as the fluorophore were prepared by the simple hydrothermal method. The morphology, structure, composition and optical properties of the prepared MoS2 QDs were characterized by Transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), UV-vis absorption and photoluminescence spectra. The results showed that the MoS2 QDs had good water dispersibility and emitted strong photoluminescence with a particle size of 2 nm. Under the optimal experimental conditions, the fluorescence signal of MoS2 QDs was quenched in the concentrations range of FOX-7 (0.5-100 µM) and the limit of detection (LOD) of the sensor was 0.19 µM. The method had been applied to analyze the real water samples with good selectivity and stability. Moreover, the quenching mechanism was studied systematically by the Fourier transform infrared (FT-IR), UV-vis absorption spectra, fluorescence lifetime, and Stern-Volmer equation, which had been proved to be static quenching. The fluorescence quenching mechanism is mainly IFE and electron transfer.

18.
Chemosphere ; 246: 125846, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31927388

RESUMO

Mesoporous CuS nanospheres (CuS-NS) decorated reduced graphene oxide (rGO) aerogel composite (3D CuS-NS/rGO) was prepared by chemical reduction process and used for the synergistic removal of Cr(VI) and cationic dyes. The porosity of the as prepared samples was determined by Bruner-Emmet-Teller (BET) surface Area. Structural and morphological properties were studied by Scanning electron microscopy (SEM) and Transmission electron microscope (TEM). These analysis revealed that the as obtained hybrid CuS-NS/rGO composite with three dimensional (3D) structure was composed of mesoporous CuS nanospheres clearly induced onto the interconnected network of rGO sheets. The photocatalytic performance of 3D CuS-NS/rGO composites was studied against the reduction of Cr(VI) and degradation of cationic dyes (MB and RhB) under visible light spectrum. Excellent photocatalytic performance was observed with 3D CuS/rGO hybrid composites as compared to the as prepared CuS nanospheres. This high photocatalytic activity was attributed to the efficient charge transfer from the mesoporous CuS nanospheres to nanosheets of rGO, which was confirmed by UV-Vis spectrometry (UV-Vis). Electrical conductivity of the prepared samples was also investigated using electrochemical impedance spectroscopy (EIS). Additionally, the as prepared hybrid composites was easy to recycle by using simple tweezers and can be a best candidate for industrial applications.


Assuntos
Cromo/química , Poluentes Ambientais/química , Nanosferas/química , Catálise , Cobre/química , Grafite , Luz , Microscopia Eletrônica de Varredura , Modelos Químicos
19.
J Hazard Mater ; 383: 121206, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31539662

RESUMO

The adsorption capacities of different ratios of 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP) and nano-hydroxyapatite (HAP) hybrid systems on Cu2+ were probed. The FTIR, XRD, SEM and EDS analyses showed that HEDP with Cu2+ adsorbed on the surface of HAP and a new crystal phase appeared. The content of adsorbed Cu2+ were 4.4% and 21.8% on the surface of single HAP and HEDP-HAP-0.5 hybrid system, respectively, and later was 4.94 times that of the former. Conversely, the Ca/P (mol) ratio decreased from 1.40 to 0.61, indicating more Ca2+ were replaced by Cu2+. Meanwhile, molecular dynamics (MD) simulations results showed that HEDP and water molecules both formed ordered adsorption layer with similar concentration profiles, but the former preferred to gather on the HAP surface than the latter. The electrovalence bonds between the phosphonic acid functional groups of HEDP and Ca2+ of HAP surface played the dominant role in their adsorption. The adsorption results showed that the maximum adsorption capacity of single hydroxyapatite for Cu2+ was 40.32 mg/g, while the maximum adsorption capacities reached 99.11, 171.8 and 147.27 mg/g for HEDP-HAP-0.2, HEDP-HAP-0.5 and HEDP-HAP-1.0 hybrid systems, respectively. The study illustrated that the adsorption process accorded with the pseudo-second-order kinetic and Langmuir isotherm model.

20.
J Int Med Res ; 48(2): 300060519877076, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31566050

RESUMO

OBJECTIVE: Rib fixation is an effective treatment for patients with multiple rib fractures. We retrospectively evaluated the application of a four-claw titanium plate in patients with rib fractures. METHODS: Fifty-four patients treated for multiple rib fractures in our hospital from 2012 to 2016 were divided into a surgery group (n = 27) and conservative treatment group (n = 27). The patients' age, sex, cause of fracture, Injury Severity Score, chest Abbreviated Injury Scale score, number of ventilator days, and length of hospitalization were recorded. RESULTS: The mean duration of mechanical ventilation was 4.5 ± 0.7 and 7.9 ± 1.7 days in the surgery and control group, respectively, with a significant difference. The length of intensive care unit stay was also significantly different between the groups (5.9 ± 0.6 vs. 10.6 ± 1.9 days, respectively). The length of hospital stay and recovery time to regular life in the surgery and control group were 11.5 ± 1.9 and 3.9 ± 4.0 days and 38.2 ± 8.3 and 60.8 ± 12.1 days, respectively, both with significant differences. CONCLUSION: A four-claw titanium plate is valuable for patients with multiple rib fractures, allowing easy fixation of broken ribs beneath the scapula, even the second rib.


Assuntos
Fraturas das Costelas , Placas Ósseas , Humanos , Escala de Gravidade do Ferimento , Tempo de Internação , Estudos Retrospectivos , Fraturas das Costelas/diagnóstico por imagem , Fraturas das Costelas/cirurgia , Resultado do Tratamento
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