Implementing large-scale synthesis of nanoporous PtNi/ccatalysts for hydrogenation processes of unsaturated organiccompounds under atmospheric pressure at temperatures below 100 degrees c is an urgent task. In this ...
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Implementing large-scale synthesis of nanoporous PtNi/ccatalysts for hydrogenation processes of unsaturated organiccompounds under atmospheric pressure at temperatures below 100 degrees c is an urgent task. In this paper, a nanoporous SPE-PtNi/c membrane electrode is prepared by ion beam sputtering, ultrasonic-assisted electrochemical dealloying, and hotpressing. Special attention is paid to the analysis of the electrochemical properties, phase structure, surface morphology, active constituent distribution, and catalytic efficiency for cyclohexene hydrogenation of the produced electrode in comparison with those of commercial Pt/ccatalysts. The results show that the ultrasonic-assisted electrochemical etching temperature exerts the most significant effect on the catalytic activity of the catalyst under consideration. In particular, the treatment of PtNi/c in 0.7 mol/L HclO4 for 1.5 h at the optimized temperature of 50 degrees c enables one to increase the catalytic activity by 25.20% at decreasing the Pt-loading content by 88.85% compared with commercial Pt/c. Furthermore, the nanoporous structure of the PtNi/c surface allows the binding energy of Pt 4f7/2 to be reduced by 0.23 eV due to the Ni loss and the crystal plane shrinkage from NiPt, which enhances the compressive strain of the lattice structure of exposed Pt and increases the number of active sites. Finally, the use of a nanoporous SPE-PtNi/c membrane electrode could increase the yield of cyclohexene during the hydrogenation reaction by 179% at simultaneously improving the current efficiency by 69%. (c) 2021 Hydrogen Energy Publications LLc. Published by Elsevier Ltd. All rights reserved.
This article interrogates the following two concepts: the 'subcultural imagination' and the 'subcultural subject'. We explore debates surrounding the ways in which interactions between the researcher a...
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This article interrogates the following two concepts: the 'subcultural imagination' and the 'subcultural subject'. We explore debates surrounding the ways in which interactions between the researcher and participant produce knowledge, in order to further establish the critical contribution of subculture within sociology. This article draws upon the notion of critique and ideas of c. Wright Mills (1959) in order to demonstrate the potential of new forms of 'imagination' within subcultures research. We seek to show through ethnographic examples how researchers and participants can be engaged in co-production of fieldwork, analysis and writing within research at different levels of engagement. The article will cover four areas, all focused on placing 'imagination' at the centre of subcultures research: first, it critiques the postmodern post-subcultural position within youth cultural studies;second, it defines the subcultural imagination and third, it explores specific empirical examples of subcultural subjects and, finally, we shall address the potential for micro co-production.
American sociologist c. Wright Mills is one of the most important and controversial sociologists of the post-war period. Of Mills' works, one book stands out: The Sociological Imagination, published by Oxford Univ...
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American sociologist c. Wright Mills is one of the most important and controversial sociologists of the post-war period. Of Mills' works, one book stands out: The Sociological Imagination, published by Oxford University Press in 1959. Little known is that Mills drafted his book during a 12-month Fulbright visit to University of copenhagen 1956-1957. In the rich biographical literature on Mills this is mentioned only in the passing, or not at all. Based on hitherto unused archival material, this paper offers the first detailed account of his copenhagen-visit during the cold War. Bringing together this bulk of new historical traces sheds new light on the year Mills himself referred to as a "pivotal moment." These 12 months in copenhagen, amid the cold War, was formative for Mills in two ways: First, copenhagen was an entrepot to European center-left thinking both east and west of the Iron curtain. Second, the stay in copenhagen offered a 'space of selfhood', allowing Mills a necessary respite to develop his critical thinking. He did so in close cooperation with like-minded colleagues in copenhagen. In the mid-1950s, the discipline was in the making in Denmark, and the visit of a prominent US scholar like Mills offered opportunities for Danish sociologist to further the discipline - and their standing within the discipline.
The large-scale synthesis of electrode materials in the field of lithium ion batteries (LIBs) is highly depending on the synthetic technique. In this paper, we developed a facile route to synthesize N-doped carbon coa...
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The large-scale synthesis of electrode materials in the field of lithium ion batteries (LIBs) is highly depending on the synthetic technique. In this paper, we developed a facile route to synthesize N-doped carbon coated silicon (Si/c) materials. In that, commercial Si flakes were ball-milled with asphalt as a carbon source and dopamine as a nitrogen source, followed by carbonization in inert atmorsphere to obtain N-doped Si/c materials. As a result, the N-doped Si/c material achieved better cycling stability and slightly higher initial charging capacity of 2265.1 mA h g(-1) than that of undoped Si/c at the current density of 200 mA g(-1). After 50 cycles, a charge capacity of 1359.1 mA h g(-1) was retained, representing 36.7% capacity enhancement compared with that of the Si/c sample (994.4 mA h g(-1)). Moreover, the rate performance of the Si-based material was also effectively improved by the N-doping. It can be explained that the N-doped carbon layer can facilitate the Li-ions diffusion. Overall, the N-doped Si/c material obtained by a simple technique is promising for the high energy density LIBs application as the anode material.
c/c-Siccomposites have enormous potential as a new generation of brake materials. It is worth studying the friction and wear behaviours of these materials in special environments to ensure the safe and effective brak...
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c/c-Siccomposites have enormous potential as a new generation of brake materials. It is worth studying the friction and wear behaviours of these materials in special environments to ensure the safe and effective braking of trains in practical applications. In this study, the braking behaviours and wear mechanisms of c/c-Sic mating with iron/copper-based PM in dry, wet and salt fog conditions are compared in detail. The results show that the coefficient of friction (cOF) in the wet condition is reduced by 14.13% compared with that under the dry condition. The cOF value of the first braking under salt fog condition is increased by 12.27% and 30.75% compared to the dry and wet conditions, respectively. Additionally, the tail warping phenomenon of the braking curve disappears in wet condition, which is attributed to the weak adhesion of friction interfaces and the lubrication of the water film. The main wear mechanisms of c/c-Sic mating with iron/copper-based PM under dry condition are adhesive, fatigue and oxidation wear. However, the dominant wear in wet condition is abrasive wear. The cooling and lubrication of water reduce the tendency of thermal stress, and weaken adhesive and fatigue wear. Furthermore, salt fog can accelerate the corrosion of alloy friction film, leading to the damage of friction film. Meanwhile, the third body particles formed in salt fog condition participate in the braking process. The wear mechanisms in salt fog condition are dominated by abrasive and delamination wear.
This study presents the results of the validation of information products on surface reflectance and NDVI, taking into account land cover types, obtained from satellite data of the chinese PMS GF-1 sensor and the refe...
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This study presents the results of the validation of information products on surface reflectance and NDVI, taking into account land cover types, obtained from satellite data of the chinese PMS GF-1 sensor and the reference data of the European sensor MSI Sentinel-2 (ESA) using image cross validation method. Based on the analysis, a high correlation of the target GF-1 information products and reference Sentinel-2 information products was revealed. The resulting regression coefficients can be used with a high degree of reliability when conducting a complex analysis of satellite data to recalculate the values obtained by the PMS sensor into the corresponding values of the MSI sensor, taking into account the camera of a specific satellite (GF-1c or GF-1B).
Purpose Probiotic species of butyrate producers have been investigated for the potential in preventing and treating obesity and overweight. However, clostridium cochlearium has not been linked with any health benefits...
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Purpose Probiotic species of butyrate producers have been investigated for the potential in preventing and treating obesity and overweight. However, clostridium cochlearium has not been linked with any health benefits. We hypothesized that c. cochlearium could be a promising new probiotic with health benefits in improving body weight control and insulin sensitivity. Methods Productions of short-chain fatty acids (ScFAs) were characterized for c. cochlearium by NMR and Gc-MS analyses. Probiotic effects of c. cochlearium were evaluated through diet-induced obese (DIO) c57BL/6 mice. The influence of c. cochlearium administration on gut ScFAs was measured using Gc-MS. Lc-MS-based untargeted metabolomic profiling and multivariate analysis were used to assess the serum metabolic alteration, identify biomarkers and pathways in response to the c. cochlearium administration. Results After 17 weeks of diet intervention, body weight gain of cc group (fed with a high-fat diet supplemented with c. cochlearium) showed a 21.86% reduction from the high-fat diet (HF) control group (P < 0.001), which was specifically reflected on the significantly lowered fat mass (cc vs HF, 17.19 g vs 22.86 g, P < 0.0001) and fat percentage (cc vs HF, 41.25% vs 47.10%, P < 0.0001), and increased lean percentage (cc vs HF, 46.63% vs 43.72%, P < 0.05). c. cochlearium administration significantly reduced fasting blood glucose from week 8 (P < 0.05 or 0.01), and eventually improved insulin sensitivity (HOMA-IR, cc vs HF, 63.77 vs 143.13, P < 0.05). Overall lowered levels of ScFAs were observed in the gut content of cc group. Metabolomic analysis enabled the identification of 53 discriminatory metabolites and 24 altered pathways between cc and HF groups. In particularly, most of the pathway-matched metabolites showed positive correlations with body weight, which included glutamate, phenylalanine, ornithine, Pcs, LPcs, Accas, proline, 5,6-dihydrouracil, pyroglutamic acid, and 1-pyrroline-4-hydroxy-2-carbo
Since its inception almost fifty years ago, Modern china has kept pace with international scholarly trends and greatly influenced global academia. As the founder and editor of Modern china, Philip c. c. Huang's ed...
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Since its inception almost fifty years ago, Modern china has kept pace with international scholarly trends and greatly influenced global academia. As the founder and editor of Modern china, Philip c. c. Huang's editorial principles, scholarly ideas, and personal theories and methodologies have been prominently embodied in the themes and contents of the journal, which has guided the development, evolution, and changing currents in the field of china studies. Reflecting back on the older methodologies of china studies, Huang abandoned the existing theoretical framework of either/or binaries and, basing himself firmly in empirical practice, pursued a new perspective focusing on the interrelationships and interpenetrations between dualities. Huang's work has laid out the path for the future development of theory and practice in china studies.
This paper explores the vertices of Jung's, Anzaldua's and Benjamin's distinct ontologies and the way in which they connect in the shared recognition that what has been estranged in human history is enigma...
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This paper explores the vertices of Jung's, Anzaldua's and Benjamin's distinct ontologies and the way in which they connect in the shared recognition that what has been estranged in human history is enigmatically lodged in the world's fabric today. cultural distress, in other words, is the outcome of what has become repudiated in the self and the collective across time. From this perspective, the paper argues that we have a collective responsibility to listen to the claims of the dead laid bare in moments of contemporary real-world danger and it elaborates the psychical dimensions of being that are cultivated in times of danger. The author contends that these psychical presences are the dead of human history including our ancestral heritage that linger and possibly may penetrate our awareness. They haunt and hold a potential to animate our movement towards a sublimatory process that can be seen as a precursor to social responsiveness and action. The author explores this through her own experience with an example of the spawning of spiritual activism within the socio-political maelstrom of AIDS.
Grape aroma precursors have been extensively studied and many glycosidically-bound terpenols and c13-norisoprenoids were identified. Instead, these compounds were scarcely investigated in green coffea arabica where ju...
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Grape aroma precursors have been extensively studied and many glycosidically-bound terpenols and c13-norisoprenoids were identified. Instead, these compounds were scarcely investigated in green coffea arabica where just few glycosidiccompounds were identified so far. By resorting to knowledge of glycoside aroma precursors in grape and the possibility to identify their structures using a high-resolution mass spectrometry database constructed for grape metabolomics, targeted investigation of glycoside precursors in green c. arabica from different geographical origins, was performed. High linalool hexose-pentose was found in all the investigated samples and hexosyl-pentoside derivatives of geraniol, linalooloxide and another linalool isomer, were identified. Moreover, two putative norisoprenoid glycosides were characterized. 13-Damascenone was detected in the volatile fraction of the examined c. arabica coffees only after acid addition, however no signals of 13-damascenone glycosides, were found. Findings suggests that this important aroma compound could form by hydrolysis and dehydration of a putative 3-hydroxy-13-damascone glycoside precursor identified for the first time in coffee. Aglycones released during the roasting process contribute to enrich the coffee aroma with their positive sensory notes and the identification of these glycosides can contribute to disclose the coffee biology including biochemical, physiological and genetic aspects.
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