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1.
Chemosphere ; 355: 141898, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38579951

RESUMO

Global warming trend is accelerating. This study proposes a green and economical methane (CH4) control strategy by plant combination in constructed wetlands (CWs). In this study, a single planting of Acorus calamus L. hybrid constructed wetland (HCW-A) and a mixed planting of Acorus calamus L. and Eichhornia crassipes (Mart.) Solms hybrid constructed wetland (HCW-EA) were constructed. The differences in nitrogen removal performance and CH4 emissions between HCW-A and HCW-EA were compared and analyzed. The findings indicated that HCW-EA demonstrated significant improvements over HCW-A, with NH4+-N and TN removal rates increasing by 21.61% and 16.38% respectively, and CH4 emissions decreased by 43.36%. The microbiological analysis results showed that plant combination promoted the enrichment of Proteobacteria, Alphaproteobacteria and Bacillus. More nitrifying bacteria carrying nxrA genes and denitrifying bacteria carrying nirK genes accelerated the nitrogen transformation process. In addition, the absolute abundance ratio of pmoA/mcrA increased, reducing the release of CH4.


Assuntos
Desnitrificação , Áreas Alagadas , Nitrogênio , Plantas , Genes Bacterianos
2.
Funct Plant Biol ; 512024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38417846

RESUMO

The MYB transcription factor (TF) are among the largest gene families of plants being responsible for several biological processes. The R2R3-MYB gene family are integral player regulating plant primary and secondary metabolism, growth and development, and responses to hormones and stresses. The phylogenetic analysis combined with gene structure analysis and motif determination resulted in division of R2R3-MYB gene family into 27 subgroups. Evidence generated from synteny analyses indicated that CqR2R3-MYBs gene family is featured by tandem and segmental duplication events. On the basis of RNA-Seq data, the expression patterns of different tissues under salt treatment were investigated resulting CqR2R3-MYB genes high expression both in roots and stem of quinoa (Chenopodium quinoa ) plants. More than half of CqR2R3-MYB genes showed expression under salt stress. Based on this result, CqR2R3-MYB s may regulate quinoa plant growth development and resistance to abiotic stresses. These findings provided comprehensive insights on role of CqR2R3-MYBs gene family members in quinoa and candidate MYB gene family members can be further studies on their role for abiotic stress tolerance in crop plants.


Assuntos
Chenopodium quinoa , Genes myb , Genes myb/genética , Filogenia , Chenopodium quinoa/genética , Chenopodium quinoa/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
3.
Environ Technol ; 44(8): 1061-1070, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34651547

RESUMO

This paper designs and builds a small constructed wetland test site to study the internal hydraulic characteristics of different types of constructed wetlands, conducts NaCl pulse tracing experiments, and fits the residence time distribution (RTD) with the CSTRs+PFD model (Continuous Stirred-Tank Reactor model in parallel with Plug Flow with Dispersion model). The results showed that, among the six types of constructed wetlands, hydraulic parameters of horizontal subsurface flow constructed wetlands with baffles had the best performance, with a tracer recovery rate (F(t)) reaching 43.67% and hydraulic efficiency (λ) reaching 0.81. The addition of baffles slowed flow velocity, increased mean hydraulic retention time (Tm) and peak residence time (Tp), and reduced the short circuits phenomenon. The velocity of internal water flow increased during the horizontal and vertical deflections, which could well avoid the stagnation phenomenon caused by complicated flow state, thereby improving the hydraulic efficiency (λ). The CSTRs+PFD model can better fit the RTD of 6 different types of constructed wetlands. The peak value of the fitted curve, the time to reach the peak and the slope of the curve are all very similar to the measured RTD.


Assuntos
Eliminação de Resíduos Líquidos , Áreas Alagadas , Eliminação de Resíduos Líquidos/métodos
4.
J Colloid Interface Sci ; 616: 234-245, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35203036

RESUMO

Transition metals with catalytic properties were expected to improve the fire resistance of the polymer. In this work, NiMoO4 nanorods decorated with Co-Ni layered double hydroxide (LDH) were fabricated and incorporated into polyurea (PUA) to improve the flame retardancy during combustion. Thermogravimetric analysis (TGA) showed that the addition of NiMoO4@Co-Ni LDH slightly decreased the initial degradation and the maximum degradation temperature. With increasing loading of NiMoO4@Co-Ni LDH, the char residue increased obviously. The combustion performance of PUA with 3.0 wt% NiMoO4@Co-Ni LDH investigated by cone calorimeter (CCT) showed that the peak heat release rate (PHRR), total heat release (THR) and smoke factor (SF) decreased by 34.41%, 12.68% and 48.65%, respectively. The existence of well-dispersed NiMoO4@Co-Ni LDH effectively enhanced the mechanical properties and flame retardant performances of PUA.


Assuntos
Retardadores de Chama , Estruturas Metalorgânicas , Cobalto , Hidróxidos/química , Molibdênio , Níquel , Polímeros , Açúcares
5.
J Colloid Interface Sci ; 605: 483-492, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34340035

RESUMO

The conductive networks for electron hopping and migration constructed by one-dimensional (1D) composite absorbers are highly desirable to improve the electromagnetic (EM) wave attenuation capacity. Herein, the Ni@Co/C@polypyrrole (PPy) composites integrating the advantages of component and microstructure were fabricated. The addition of Co/C and PPy effectively optimized the impedance matching and improved the EM attenuation. Under the comprehensive impacts of multiple reflections/scattering, conduction loss and interface polarization, the Ni@Co/C@PPy composites showed superior EM wave absorption with the reflection loss (RL) value of -48.76 dB and the effective absorption bandwidth (EAB) of 5.10 GHz at a corresponding thickness of 2.0 mm. The largest EAB could reach 5.54 GHz (7.24-12.78 GHz) at the thickness of 2.2 mm. This work provides a great reference for fabricating 1D novel EM wave absorption materials.

6.
Water Sci Technol ; 84(3): 632-643, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34388123

RESUMO

The water body inside the constructed wetland is affected by various factors, and the flow state is relatively complicated. There will always be a certain degree of low velocity area and rapid outflow phenomenon, which makes part of the space in the wetland unable to be effectively used. Based on Computational Fluid Dynamics (CFD) technology, this paper uses Fluent's porous media model and discrete phase model to establish a hydrodynamic model of up and down baffled subsurface flow constructed wetland system. The internal flow field of the wetland is simulated, and the hydraulic performance of different baffle settings and substrate laying methods in the wetland is systematically evaluated. The results show that when the number of baffles is the same, the hydraulic efficiency is higher when the first baffle is located on the lower part of the substrate. Compared with the position of the baffle, the increase in the number of baffles does not significantly improve the hydraulic efficiency of the constructed wetland. The substrate layer thickness ratio has a significant effect on the two parameters of the variance of the hydraulic residence time distribution (σ2) and the flow divergence (σ02). By increasing the thickness of the middle substrate, the low flow rate phenomenon caused by the small porosity substrate area of the upper layer and the rapid outflow phenomenon of the lower substrate can be improved to a certain extent, the utilization efficiency of the middle substrate layer is improved, and the hydraulic performance is increased. The research results are of great significance for improving the utilization of wetland space and ensuring its efficient decontamination and purification function.


Assuntos
Purificação da Água , Áreas Alagadas , Simulação por Computador , Hidrodinâmica , Eliminação de Resíduos Líquidos
7.
J Colloid Interface Sci ; 602: 602-611, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34146948

RESUMO

Nowadays, ferrites/carbon fibers have attracted considerable attention as microwave absorption materials (MA) due to the synergistic effect between dielectric and magnetic loss. Herein, the ZnFe2O4/C fibers were fabricated via electrospinning and calcination methods, and then polypyrrole (PPy) successfully coated on the fibers via oxidative polymerization. The ZnFe2O4/C@PPy composites exhibit enhanced EM wave absorption performance with the loading of 25 wt%. The optimal reflection loss (RL) value is up to -66.34 dB (13.80 GHz) and effective absorption bandwidth (EAB) is 5.74 GHz (11.78-17.52 GHz) with a matching thickness of 1.93 mm. Besides, high-efficient absorption performance of the ZnFe2O4/C@PPy composites is mainly attributed to the dielectric loss and ideal impedance matching. This study reveals a novel approach to development of ferrites/carbon fibers coated with PPy, and the ZnFe2O4/C@PPy composites exhibit great potential application as the materials with high-efficient absorption properties.

8.
J Colloid Interface Sci ; 600: 209-218, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030004

RESUMO

Metal-organic framework (MOF) materials have caused widespread concerns in the field of microwave absorption, due to the unique microstructure and electronic state. Herein, the CoZn/C@MoS2@polypyrrole (PPy) composites were prepared through MOF self-template method. The MoS2 sheets and PPy shell incorporated for optimizing impedance matching of two-dimensional (2D) CoZn/C composites. The introduction of MoS2 sheets and PPy shell endowed the composites with enhanced microwave absorption. The as-prepared CoZn/C@MoS2@PPy composites showed a minimum reflection loss (RL) of -49.18 dB with the thickness of 1.5 mm. In addition, the effective absorption bandwidth (EAB, RL values exceeding -10 dB) covered 4.56 GHz, which showed greater performances than CoZn/C composites under a lower thickness (<2 mm). This work not only provides a facile route for fabricating MOF-derived carbon-based composites as microwave absorbers, but also broadens the application of MOF materials.

9.
RSC Adv ; 11(27): 16572-16591, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35479149

RESUMO

Microwave absorbing materials (MAM) have attracted considerable attention over the years in stealth and information technologies. Metal-organic framework (MOF) with a unique microstructure and electronic state has become an attractive focus as self-sacrificing precursors of microwave absorbers. The MOF-derived porous carbon (PC) materials exhibit a high absorbing performance due to the stable three-dimensional structure and homogeneous distribution of metal particles. MOF-derived PC materials are promising for ideal MAM via tuning of the structure and composition, resulting in appropriate impedance matching and the synergistic effect between magnetic and dielectric loss. In this review, the MOF-derived PC materials and their basic absorption mechanisms (dielectric loss, magnetic loss and impedance matching) are introduced, as well as the characters of various MOF-derived PC materials. In addition, this review provides a comprehensive introduction and tabulates the recent progress based on the classification of the MOF-derived metallic state, such as pure PC (without reduced metals), mono-metal/PC, multi-metal/PC, metal oxides/PC and other derived PC composites. Finally, the challenges faced by MOF-derived PC materials are overviewed, and their further development is mentioned.

10.
Biomed Res Int ; 2020: 7350781, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32337271

RESUMO

This retrospective study investigated whether podocalyxin expression in renal biopsies and urine of patients with diabetic nephropathy (DN) is associated with renal function. This retrospective study included 32 patients with nephropathy, secondary to type 2 diabetes treated at the First Hospital of Lanzhou University (January 2010 to January 2015). Compared with the control group, the DN group had a significantly lower renal expression of podocalyxin and higher urinary podocalyxin/creatinine ratio. Patients with DN were divided into the high and low expression groups according to podocalyxin expression in renal tissues. Patients in the low expression group had longer diabetes duration, lower plasma albumin and eGFR, higher glycated hemoglobin (HbA1c), 24 h urinary protein, serum creatinine, and urinary podocalyxin/creatinine ratio, and more severe glomerular, tubulointerstitial, and renal interstitial inflammation than patients in the high expression group (all P < 0.01). The renal survival rate was significantly lower in the low expression group than in the high expression group (P < 0.01). Single-factor Cox regression analysis showed that reduced podocalyxin expression and increased urinary podocalyxin excretion were associated with poor renal outcome. Measuring podocalyxin levels in renal tissues and urine could help evaluate the progression of DN.


Assuntos
Nefropatias Diabéticas/metabolismo , Rim/metabolismo , Sialoglicoproteínas/metabolismo , Biomarcadores/sangue , Biomarcadores/urina , Estudos de Casos e Controles , Creatinina/sangue , Creatinina/metabolismo , Creatinina/urina , Diabetes Mellitus Tipo 2/complicações , Feminino , Taxa de Filtração Glomerular , Hemoglobinas Glicadas/metabolismo , Humanos , Inflamação , Rim/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Albumina Sérica , Sialoglicoproteínas/urina , Taxa de Sobrevida
11.
RSC Adv ; 9(40): 23241-23253, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35514486

RESUMO

Considering the characteristics of abundant narrow micropores of <1 nm, appropriate proportion of mesopores/macropores and suitable surface functionalization for a highly-efficient carbon-based CO2 adsorbent, we proposed a facile and cost-effective strategy to prepare N and S dual-doped carbons with well-interconnected hierarchical pores. Benefiting from the unique structural features, the resultant optimal material showed a prominent CO2 uptake of up to 7.76 and 5.19 mmol g-1 at 273 and 298 K under 1 bar, and importantly, a superb CO2 uptake of 1.51 mmol g-1 at 298 K and 0.15 bar was achieved, which was greatly significant for CO2 capture from the post-combustion flue gases in practical application. A systematic study demonstrated that the synergetic effect of ultramicroporosity and surface functionalization determined the CO2 capture properties of porous carbons, and the synergistic influence mechanism of nitrogen/sulfur dual-doping on CO2 capture performance was also investigated in detail. Importantly, such as-prepared carbon-based CO2 adsorbents also showed an outstanding recyclability and CO2/N2 selectivity. In view of cost-effective fabrication, the excellent adsorption capacity, high selectivity and simple regeneration, our developed strategy was valid and convenient to design a novel and highly-efficient carbonaceous adsorbent for large-scale CO2 capture and separation from post-combustion flue gases.

12.
Open Med (Wars) ; 13: 597-604, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519637

RESUMO

OBJECTIVE: To investigate the clinical pathology and prognosis & outcome of Henoch-Schonlein purpura nephritis (HSPN) with renal interstitial lesions. METHODS: All 148 patients were analyzed for clinical, renal pathological, and prognostic features. Patients with no, mild, and moderate- severe renal tubulo-interstitial lesions were included in group A, B and C, respectively. RESULTS: The estimated glomerular filtration rate (eGFR) of group B was significantly lower than that of group A. The levels of serum creatinine and blood urea nitrogen in group C were significantly higher than those in groups A and B. Clinical type II was correlated with pathological types II and IIIa; pathological type IV and IIIb were correlated with clinical type VI and IV. There were significant differences in the level of red blood cells in urinary sediment, levels of urine occult blood and in the prognosis among the 3 groups. CONCLUSION: Clinically, Type II is the most common cause; pathologically, Type IIIa is more common. The severity of renal tubulo-interstitial lesions is positively correlated with a decline in renal function and GFR. There is a correlation between the severity of renal tubulo-interstitial lesions and the severity of hematuria. Most patients with HSPN have a good prognosis.

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