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排序方式: 共有247条查询结果,搜索用时 46 毫秒
81.
Insight into Ca‐Substitution Effects on O3‐Type NaNi1/3Fe1/3Mn1/3O2 Cathode Materials for Sodium‐Ion Batteries Application
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Liqi Sun Yingying Xie Xiao‐Zhen Liao Hong Wang Guoqiang Tan Zonghai Chen Yang Ren Jihyeon Gim Wan Tang Yu‐Shi He Khalil Amine Zi‐Feng Ma 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(21)
O3‐type NaNi1/3Fe1/3Mn1/3O2 (NaNFM) is well investigated as a promising cathode material for sodium‐ion batteries (SIBs), but the cycling stability of NaNFM still needs to be improved by using novel electrolytes or optimizing their structure with the substitution of different elements sites. To enlarge the alkali‐layer distance inside the layer structure of NaNFM may benefit Na+ diffusion. Herein, the effect of Ca‐substitution is reported in Na sites on the structural and electrochemical properties of Na1?xCax/2NFM (x = 0, 0.05, 0.1). X‐ray diffraction (XRD) patterns of the prepared Na1?xCax/2NFM samples show single α‐NaFeO2 type phase with slightly increased alkali‐layer distance as Ca content increases. The cycling stabilities of Ca‐substituted samples are remarkably improved. The Na0.9Ca0.05Ni1/3Fe1/3Mn1/3O2 (Na0.9Ca0.05NFM) cathode delivers a capacity of 116.3 mAh g?1 with capacity retention of 92% after 200 cycles at 1C rate. In operando XRD indicates a reversible structural evolution through an O3‐P3‐P3‐O3 sequence of Na0.9Ca0.05NFM cathode during cycling. Compared to NaNMF, the Na0.9Ca0.05NFM cathode shows a wider voltage range in pure P3 phase state during the charge/discharge process and exhibits better structure recoverability after cycling. The superior cycling stability of Na0.9Ca0.05NFM makes it a promising material for practical applications in sodium‐ion batteries. 相似文献
82.
Giménez JB Carretero L Gatti MN Martí N Borrás L Ribes J Seco A 《Water science and technology》2012,66(3):494-502
The anaerobic treatment of sulphate-rich wastewater causes sulphate reducing bacteria (SRB) and methanogenic archaea (MA) to compete for the available substrate. The outcome is lower methane yield coefficient and, therefore, a reduction in the energy recovery potential of the anaerobic treatment. Moreover, in order to assess the overall chemical oxygen demand (COD) balance, it is necessary to determine how much dissolved CH(4) is lost in the effluent. The aim of this study is to develop a detailed and reliable method for assessing the COD mass balance and, thereby, to establish a more precise methane yield coefficient for anaerobic systems treating sulphate-rich wastewaters. A submerged anaerobic membrane bioreactor (SAMBR) treating sulphate-rich municipal wastewater was operated at 33 °C for an experimental period of 90 d, resulting in a high COD removal (approximately 84%) with a methane-enriched biogas of 54 ± 15% v/v. The novelty of the proposed methodology is to take into account the sulphide oxidation during COD determination, the COD removed only by MA and the dissolved CH(4) lost with the effluent. The obtained biomethanation yield (333 L CH(4) kg(-1) COD(REM MA)) is close to the theoretical value, which confirms the reliability of the proposed method. 相似文献
83.
A Díaz Borrás R Vila Aguilar E Hernández Giménez 《International journal of food microbiology》1988,7(1):79-85
In vitro and in vivo tests were carried out to study the inhibitory effect of mixtures of sodium orthophenylphenate, methyl-1-(butyl-carbamoyl)-2-benzimidazole ('Benomyl') and sodium orthophenylphenate, 2-(4-thiazolil)-benzimidazole ('Thiabendazole') on growth of strains of Penicillium italicum and P. digitatum resistant to sodium orthophenylphenate, 'Benomyl' and 'Thiabendazole'. 'In vitro' tests showed a synergistic effect of the mixtures; 10 ppm of sodium orthophenylphenate and 10 ppm of the benzimidazolic compound in most cases resulted in complete growth inhibition. Navel oranges inoculated with P. italicum spores showed no damage after 7 days of incubation at 25 degrees C and 80-90% relative humidity when treated with a mixture of 100 ppm of sodium orthophenylphenate and 100 ppm of Thiabendazole. 相似文献
84.
As it is more environmentally sound and friendly than conventional energy technologies that emit carbon dioxide, hydrogen technology can play a key role in solving the problems caused by the greenhouse gas effect and in coping with the hydrogen economy. Numerous countries around the world, including Korea, have increasingly focused on R&D where hydrogen technology development is concerned. This paper focuses on the use of the fuzzy analytic hierarchy process (fuzzy AHP), which is an extension of the AHP method and uses interval values to reflect the vagueness of human thought, to assess national competitiveness in the hydrogen technology sector. This analysis based on the AHP and fuzzy AHP methods revealed that Korea ranked 6th in terms of national competitiveness in the hydrogen technology sector. 相似文献
85.
Synthesis of polyunsaturated fatty acid-enriched triglycerides by lipase-catalyzed esterification 总被引:2,自引:0,他引:2
L. Esteban Cerdán A. Robles Medina A. Giménez Giménez M. J. Ibáñez González E. Molina Grima 《Journal of the American Oil Chemists' Society》1998,75(10):1329-1337
This paper reports on the synthesis of triglycerides by enzymatic esterification of polyunsaturated fatty acids (PUFA) with
glycerol. A PUFA concentrate obtained from cod liver oil was used to optimize the reaction to favor triglyceride synthesis
with lipases. The type and amount of lipase and organic solvent, glycerol content, temperature, water content, and amount
and time of addition of molecular sieves were studied. The optimal reaction mixture and conditions were: 9 mL hexane, 60°C,
0.5% (vol/vol) water, 1 g molecular sieves added after 24 h of reaction, glycerol/fatty acid molar ratio 1:3 and 100 mg of
Novozym 435 (Novo Nordisk A/S) lipase. Under these conditions, an enriched triglyceride yiedl of 84.7% containing 27.4% eicosapentaenoic
acid and 45.1% docosahexaenoic acid was obtained from a cod liver oil PUFA concentrate. 相似文献
86.
P Cuevas V Barrios G Giménez-Gallego V Martinez-Coso B Cuevas J Benavides J Garcia-Segovia E Asin-Cardiel 《Canadian Metallurgical Quarterly》1997,2(7):282-284
As it has been reported that basic fibroblast growth factor (bFGF) is a circulating peptide and bFGF gene expression is increased after myocardial ischemia, this study was designed to investigate the serum levels of bFGF in patients with acute myocardial infarction (AMI). Using a bFGF enzyme-linked immunoassay, bFGF levels were determined in venous blood of 15 patients with AMI on admission, at 10 days, and 30 days after infarction, and of 15 age-matched healthy volunteers who were used as controls. bFGF serum levels on admission were similar to normal values (7.48 +/- 2.3 vs 8.14 +/- 2.9 pg/ml). However, they significantly increased (16.82 +/- 3.4 pg/ml; p <0.05) 10 days after the onset of AMI, and at 30 days they returned to baseline (7.07 +/- 2.9 pg/ml). The increased bFGF levels at the second week post AMI suggest that bFGF plays an important role in mediating the development of coronary collateral circulation after myocardial ischemia in humans. 相似文献
87.
M Casado A Bendahan F Zafra NC Danbolt C Aragón C Giménez BI Kanner 《Canadian Metallurgical Quarterly》1993,268(36):27313-27317
High affinity sodium- and potassium-coupled L-glutamate transport into presynaptic nerve terminals and fine glial processes removes the neurotransmitter from the synaptic cleft, thereby terminating glutamergic transmission. This report describes that the purified L-glutamate transporter from pig brain is phosphorylated by protein kinase C, predominantly at serine residues. Upon exposure of C6 cells, a cell line of glial origin, to 12-O-tetradecanoylphorbol-13-acetate, about a 2-fold stimulation of L-glutamate transport is observed within 30 min. Concomitantly, the level of phosphorylation increases with similar kinetics. The phorbol ester also stimulates L-glutamate transport in HeLa cells infected with a recombinant vaccinia virus expressing T7 RNA polymerase and transfected with pT7-GLT-1. The latter is a recently cloned rat brain glutamate transporter of glial origin. Mutation of serine 113 to asparagine does not affect the levels of expressed transport but abolishes its stimulation by the phorbol ester. To our knowledge, this is the first direct demonstration of the regulation of a neurotransmitter transporter by phosphorylation. 相似文献
88.
JM Manterola F Gamboa E Padilla J Lonca L Matas A Hernández M Giménez PJ Cardona B Vi?ado V Ausina 《Canadian Metallurgical Quarterly》1998,17(11):773-777
The MB/BacT (Organon-Teknika, USA) is a fully automated, rapid, nonradiometric system for the culture of mycobacteria from clinical samples. The rate of recovery of mycobacteria and the time to detection obtained with the MB/ BacT were compared with those obtained with L?wenstein-Jensen and Coletsos solid media and Bactec 7H12 (12B) (Becton-Dickinson, USA) broth when 600 processed specimens were inoculated into all media in parallel. Specimens included 383 respiratory samples, 20 urine samples, 23 purulent exudates, 13 stool samples, 103 blood samples, 14 bone marrow aspirates, and 44 body fluid samples or aspirates. Overall, 106 mycobacterial isolates comprising six species were recovered, of which 100 (94.3%) were detected with MB/BacT, 98 (92.5%) with egg-based media, and 96 (90.2%) with Bactec 12B. The recovery rates of Mycobacterium tuberculosis complex with MB/BacT, egg-based media, and Bactec 12B were 98.7%, 93.7, and 89.9%, respectively. The average number of days to detection of single mycobacterial isolates was 14.2 days for MB/BacT, 26.1 days for egg-based media, and 11.7 days for Bactec 12B. The contamination rates were higher in MB/BacT (5%) than in Bactec 12B (1.8%) or egg-based media (1.5%). MB/BacT is a reliable, nonradiometric, less labor-intensive alternative to Bactec 12B for recovery of mycobacteria, but, as with other liquid culture methods, MB/BacT should be used in combination with a solid medium, not on its own. 相似文献
89.
JL Lanciego FG Wouterlood E Erro JM Giménez-Amaya 《Canadian Metallurgical Quarterly》1998,110(5):509-515
It is appropriate that this Special Section in Journal of Adolescence should focus on the needs of adolescents within the care system. The year 1998 marks the fiftieth anniversary of the passing of the Children Act (1948), which established the modern structure of services in England and Wales for children and adolescents deprived of adequate parenting in their own homes. Anniversaries are an opportunity for reflection. Are our current services an improvement on the past? In learning new lessons have we possibly lost sight of things we knew better, and did better, previously? 相似文献
90.