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1.
Phys Chem Chem Phys ; 17(7): 5084-9, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25599343

RESUMO

The application of the graphitic anode is restricted by its low theoretical specific capacity of 372 mA h g(-1). Higher capacity can be achieved in the graphitic anode by modifying its structure, but the detailed storage mechanism is still not clear. In this work, the mechanism of the lithium storage in a disordered graphitic structure has been systematically studied. It is found that the enhanced capacity of the distorted graphitic structure does not come from lithium-intercalation, but through a capacitive process, which depends on the disordering degree and the porous structure.

2.
Materials (Basel) ; 16(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37629818

RESUMO

This research paper investigated the impact of normal annealing (NA) and magnetic field annealing (FA) on the soft magnetic properties and microstructure of Fe82Si2B13P1C3 amorphous alloy iron cores. The annealing process involved various methods of magnetic field application: transverse magnetic field annealing (TFA), longitudinal magnetic field annealing (LFA), transverse magnetic field annealing followed by longitudinal magnetic field annealing (TLFA) and longitudinal magnetic field annealing followed by transverse magnetic field annealing (LTFA). The annealed samples were subjected to testing and analysis using techniques such as differential scanning calorimetry (DSC), transmission electron microscopy (TEM), X-ray diffraction (XRD), magnetic performance testing equipment and magneto-optical Kerr microscopy. The obtained results were then compared with those of commercially produced Fe80Si9B11. Fe82Si2B13P1C3 demonstrated the lowest loss of P1.4T,2kHz = 8.1 W/kg when annealed in a transverse magnetic field at 370 °C, which was 17% lower than that of Fe80Si9B11. When influenced by the longitudinal magnetic field, the magnetization curve tended to become more rectangular, and the coercivity (B3500A/m) of Fe82Si2B13P1C3 reached 1.6 T, which was 0.05 T higher than that of Fe80Si9B11. During the 370 °C annealing process of the Fe82Si2B13P1C3 amorphous iron core, the internal stress in the strip gradually dissipated, and impurity domains such as fingerprint domains disappeared and aligned with the length direction of the strip. Consequently, wide strip domains with low resistance and easy magnetization were formed, thereby reducing the overall loss of the amorphous iron core.

3.
Materials (Basel) ; 15(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35591540

RESUMO

In this paper, the corrosion resistance of FeCoSiBPC amorphous alloy after pre-oxidation and non-oxidation heat treatment is investigated. The corrosion behaviors of Fe80Co3Si3B10P1C3 amorphous alloys in 1 mol/L NaCl solution were investigated by the electrochemical workstation. The pre-oxidation heat treatment can improve the corrosion resistance of FeCoSiBPC amorphous alloy through an increase in the Ecorr value from -0.736 to -0.668 V, which makes it easy to reach a passive state. The corroded morphology and products of amorphous alloys were tested by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The SEM/TEM analysis showed that, after pre-oxidation treatment, the oxide layer was divided into two layers: the inner layer was amorphous, the outer layer appeared crystalline, and the main oxide was Fe2O3. During the oxidation process, Co and P elements diffused from the inner layer to the outer layer, forming phosphorus and cobalt oxides with high corrosion resistance on the surface of the ribbon, thereby improving the corrosion resistance of the ribbon.

4.
Bioresour Technol ; 335: 125267, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33992912

RESUMO

The multistage bio-contact oxidation reactor (BCOR) is a widely used biological strategy to treat wastewater, however, little is known about the performance and microbial community information of BCOR during the treatment of low-COD and high-salinity oilfield produced water. In this study, the performance of a multistage BCOR in treating produced water was investigated. The result suggested the BCOR could efficiently remove COD, BOD5, NH4+-N, and oil pollutants. Besides, high-throughput sequencing analysis revealed that oil content was the main variable in shaping the community structure. The highest total relative abundance of potential pollutants degraders in first BCOR stage suggested significant role of this stage in pollutants removal. In addition, the correlation analysis disclosed the key functional genera during the degradation process, including Rhodobacter, Citreibacter, and Roseovarius. Moreover, network analysis revealed that the microbial taxa within same module had strong ecological linkages and specific functions.


Assuntos
Microbiota , Salinidade , Reatores Biológicos , Campos de Petróleo e Gás , Eliminação de Resíduos Líquidos , Águas Residuárias , Água
5.
Materials (Basel) ; 11(7)2018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-29986382

RESUMO

Herein, we demonstrate the successful synthesis of novel Fe80Si9B(11−x)Px (x = 0, 1, 3, 5, 7) ultra-thick amorphous ribbons by planar flow casting. The influence of P alloying on glass forming ability (GFA), microstructure, thermal stability, soft magnetic properties, and ductility has been systematically investigated. The results reveal that introduction of P into Fe80Si9B11 alloy can remarkably enhance the GFA and increase critical thickness (tc) of the alloy from 45 to 89 um. Furthermore, the annealed FeSiBP amorphous alloys exhibited excellent soft magnetic properties, including high saturation magnetic flux density of 1.54 T, the low coercivity of 1.5 A/m, and low core losses of 0.15 W/kg. In addition, the representative Fe80Si9B8P3 ultra-thick amorphous alloy demonstrate excellent ductility even after annealing at 400 °C for 10 min, which indicates the superior performance of P-doped FeSiB alloys as compared to the commercial Fe78Si9B13 (Metglas 2605 S2) alloy. The combination of high GFA, excellent ductility, and low core losses of newly developed FeSiBP amorphous soft magnetic alloys makes them attractive candidates for magnetic applications in the high-frequency and high-speed electric devices.

6.
Sci Rep ; 8(1): 5680, 2018 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-29632333

RESUMO

The structural, magnetic, and electronic properties of Fe82Si4B10P4 metallic glass were systemically investigated by theoretical simulations. Strong atomic interaction between Fe and metalloid atoms can be observed, while the direct metalloid-metalloid atomic bonds are rare due to the solute-solute avoidance effect. The calculated value of saturation magnetic flux density (B S ) is ~1.65 T, approaching to experimental result, which is contributed by not only the electron exchange between Fe and metalloid atoms, but also the p-d orbital hybridization of Fe atoms. Moreover, Fe atoms with neighboring P atom behaving larger magnetic moments reveals the important role of P element for promoting the B S value. The potential correlation between magnetic behaviors and the local atomic packing in this study sheds some light on the structural origin of the soft magnetic properties and, thereby the theoretical guidance for the development of new soft-magnetic metallic glasses.

7.
Sci Rep ; 7: 43582, 2017 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-28240247

RESUMO

Recently, metal phosphides have been investigated as potential anode materials because of higher specific capacity compared with those of carbonaceous materials. However, the rapid capacity fade upon cycling leads to poor durability and short cycle life, which cannot meet the need of lithium-ion batteries with high energy density. Herein, we report a layer-structured GeP3/C nanocomposite anode material with high performance prepared by a facial and large-scale ball milling method via in-situ mechanical reaction. The P-O-C bonds are formed in the composite, leading to close contact between GeP3 and carbon. As a result, the GeP3/C anode displays excellent lithium storage performance with a high reversible capacity up to 1109 mA h g-1 after 130 cycles at a current density of 0.1 A g-1. Even at high current densities of 2 and 5 A g-1, the reversible capacities are still as high as 590 and 425 mA h g-1, respectively. This suggests that the GeP3/C composite is promising to achieve high-energy lithium-ion batteries and the mechanical milling is an efficient method to fabricate such composite electrode materials especially for large-scale application.

8.
Di Yi Jun Yi Da Xue Xue Bao ; 25(8): 1007-8, 1011, 2005 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16109562

RESUMO

OBJECTIVE: To explore the clinical significance of changes in urine microalbumin (UM) and endothelin (ET) in different courses of type 2 diabetes. METHODS: A clinical analyses of 30 type 2 diabetic patients with vascular complications (group A) was conducted in comparison with type 2 diabetic patients without vascular complications (group B) and patients with impaired glucose tolerance (IGT, group C). With 30 healthy subjects with family history of type 2 diabetes (group D) and 30 healthy subjects without such family history (group E) as controls, UM and ET were determined in all the subjects for a statistical analysis. RESULTS: Significant differences in UM content was noted between group A and the other 4 groups (P<0.05), while the content did not differ significantly between the latter 4 groups (P>0.05). ET content was significantly higher in group A than in the other 4 groups (P<0.01), and was the lowest in group E (P<0.01). CONCLUSIONS: Type 2 diabetic patients sustain extensively impaired endothelium function, which is exacerbated with the progression of the disease courses. Synchronized changes between vascular complications and impaired endothelium function indicates that vascular endothelial injury relates to vascular complications and the progression of diabetes.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/sangue , Nefropatias Diabéticas/sangue , Endotelinas/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Di Yi Jun Yi Da Xue Xue Bao ; 25(6): 729-31, 2005 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15958323

RESUMO

OBJECTIVE: To observe the changes in urine albumin (UALB), von Willebrand factor (vWF) and platelet-activating factor (PAF) in different courses of type 2 diabetes. METHODS: Levels of UALB, vWF and PAF were determined in 30 type 2 diabetic nephropathy patients(group A), type 2 diabetic patients without DNP(group B, n=30), patients with impaired glucose tolerance (group C, n=30), the first-degree relatives of type 2 diabetic patients with normal glucose tolerance(group D, n=30) and 30 normal glucose tolerance subjects without family history of type 2 diabetes(group E). RESULTS: UALB and PAF contents were significantly higher in group A than in the other groups (P<0.01), while between the latter 4 groups, the contents showed no significant differences (P>0.05). Serum vWF level was significantly higher in group A than those in the other groups (P<0.05). CONCLUSIONS: Renal dysfunction and platelet activation are present in type 2 diabetes with microvascular complications, and the synchronized changes between renal dysfunction and platelet activation indicate the involvement of elevated PAF in vascular injury.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Nefropatias Diabéticas/sangue , Fator de Ativação de Plaquetas/metabolismo , Fator de von Willebrand/metabolismo , Adulto , Idoso , Albuminúria/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
J Mol Diagn ; 15(5): 642-51, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23810501

RESUMO

The predominant determinants of α-thalassemia are deletions in the human α-globin gene cluster. A rapid DNA-based assay is needed for mass screening in thalassemia-prevention programs. Herein, we established a novel quadruplex TaqMan qPCR gene dosage assay with two separate combination reactions. The assay directly determined the copy number of human α-globin genes based on relative quantitation of three target genes (HBA2, HBA1, and HBZ or HBPA1) versus a control gene (CREBBP). The assay showed good accuracy, with mean intra-assay and interassay variations of 3.31% ± 1.02% and 5.49% ± 0.32%, respectively. The assay was evaluated using 678 pretyped clinical DNA samples containing six α-thalassemia deletions in 13 genotypes and 186 normal samples previously screened by multiplex ligation-dependent probe amplification or gap PCR. As determined by the 2(-ΔΔCq) method, deleted gene dosage ratios were 0.46 to 0.60 in heterozygotes, 0.0 in homozygotes, and 0.97 to 1.07 in nondeleted samples. We found 99.3% concordance between the quantitative PCR and multiplex ligation-dependent probe amplification or gap-PCR results. Furthermore, routine screening for α-thalassemia deletions was performed on 3000 random samples in a blind analysis. Results for all 279 positives, which had different deletions, were fully coincident with results from standard methods. We also identified two novel deletions confirmed by multiplex ligation-dependent probe amplification. Assays using the novel method are simple and suitable for rapid genotyping and mass screening.


Assuntos
Dosagem de Genes , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase Multiplex , Reação em Cadeia da Polimerase em Tempo Real , Talassemia alfa/diagnóstico , Ordem dos Genes , Genótipo , Humanos , Programas de Rastreamento , Tipagem de Sequências Multilocus/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , alfa-Globinas/genética , Talassemia alfa/genética
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