1,897 research outputs found
A microcalorimetric study of concentration effects on the reaction entropy during Al- and Li- bulk deposition and of phase transitions during Li intercalation in graphite electrodes
In der vorliegenden Arbeit wurde der Einfluss der Konzentration auf die Entropieänderung bei der elektrochemischen Abscheidung von Al und Li und die Interkalation von Lithium in Graphit untersucht. Die Messung der Wärmeentstehung erfolgte mittels elektrochemischer Mikrokalorimetrie unter inerten Bedingungen in einer Glovebox. Die reversibel ausgetauschte Wärme entspricht gerade der Entropieänderung des Systems bei der Reaktion und beinhaltet die Beiträge aller ablaufenden Prozesse.
Die Al Bulkabscheidung wurde in Aluminiumchlorid und 1-Butyl-3-methylimidazoliumchlorid (BMIMCl) mit unterschiedlichen Verhältnissen von AlCl3 zu BMIMCl (von 1,1:1 bis 1,7:1) durchgeführt. Die Reaktionsentropie für die Aluminiumabscheidung betrug ca. 33 J/(mol K) für ein Verhältnis von AlCl3 zu BMIMCl von 1,7:1. Eine positive Abscheidungsentropie bedeutet, dass die Arbeitselektrode sich während der Abscheidung abkühlt. Die Reaktionsentropie für die Aluminiumabscheidung nahm mit dem Verhältnis von AlCl3 zu BMIMCl ab.
Die Lithiumabscheidung wurde aus 0,01 M, 0,1 M und 1 M Lösung von LiPF6 in einer 1:1 Mischung aus Ethylencarbonat (EC) und Dimethylcarbonat (DMC) (EC : DMC = 1 : 1) als Elektrolyt durchgeführt. Die Peltierwärme nahm um 5 kJ/mol bei einer Verdünnung von 1:10 und um 10 kJ/mol bei einem Verdünnungsfaktor von 100 ab. Die gemessenen Variationen des Peltier-Koeffizienten können gut durch die Änderung der Entropie des solvatisierten Li+ Ions bei Verdünnung erklärt werden.
Die Reaktionsentropie für die Lithiuminterkalation in Graphit wurde in Abhängigkeit vom Ladezustand der Graphitelektrode untersucht. Es wurde im Mittel ein linearer Zusammenhang zwischen dem Interkalationspotential und der Interkalationsentropie zwischen 0,3 V und 0,07 V gefunden. Der Proportionalitätsfaktor entsprach der Faraday-Konstante. Die reversible Wärme und die Reaktionsentropie für die Phasenübergänge der coexistierenden Stufenphasen in Graphit wurden bestimmt, was dem Beitrag der Reaktionsenthalpie während Phasenübergängen entspricht. Die Änderung der Reaktionsentropie wurde durch das Gittergasmodell beschrieben und kann als Mischungsentropie von Lithium in Graphit interpretiert werden. Bei der Bildung von SEI-Schichten wurde eine Kälteentwicklung beobachtet, was auf die reversible Reaktionen schließen ließ, da eine irreversible Reaktion nur einen Erwärmungseffekt der Elektrode bewirken würde
A Process Development Project For A Case Company
This paper presents a case study on a process improvement project undertaken by a company in the sustainable energy industry. The project aimed to optimize the gate model for new product development, implement a hybrid-gate model, develop a gate checklist, and create an R&D process flow chart to better manage the R&D process. The study began with a thorough analysis of the existing gate model, which revealed several bottlenecks and inefficiencies. These were addressed through a series of process improvements, including better definition of gate criteria, improved cross-functional collaboration, and enhanced communication with stakeholders. To further improve the R&D process, the company implemented a hybrid-gate model, which integrated elements of both the stage-gate and agile development methodologies. This approach enabled the company to be more responsive to changes in the market and customer needs while maintaining the discipline and rigor of the stage-gate model. In addition, the project team developed a gate checklist, which provided a standardized set of criteria to evaluate project progress at each gate. This allowed the team to identify and address potential issues early in the development process. To provide greater visibility and understanding of the R&D process, the team also created an R&D process flow chart, which outlined the steps involved in new product development and the flow of information and decision-making. The project was successful in improving the efficiency and effectiveness of the R&D process, resulting in faster time-to-market for new products and increased customer satisfaction. The gate checklist and R&D process flow chart provided greater transparency and accountability, helping to ensure that projects were delivered on time and within budget. Overall, this case study demonstrates the importance of continuous process improvement in the sustainable energy industry and highlights the potential benefits of a hybrid-gate model, gate checklist, and R&D process flow chart for managing complex development projects
Entanglement and chaos in warped conformal field theories
Various aspects of warped conformal field theories (WCFTs) are studied
including entanglement entropy on excited states, the Renyi entropy after a
local quench, and out-of-time-order four-point functions. Assuming a large
central charge and dominance of the vacuum block in the conformal block
expansion, (i) we calculate the single-interval entanglement entropy on an
excited state, matching previous finite temperature results by changing the
ensemble; and (ii) we show that WCFTs are maximally chaotic, a result that is
compatible with the existence of black holes in the holographic duals. Finally,
we relax the aforementioned assumptions and study the time evolution of the
Renyi entropy after a local quench. We find that the change in the Renyi
entropy is topological, vanishing at early and late times, and nonvanishing in
between only for charged states in spectrally-flowed WCFTs.Comment: 31 pages; v2: corrected typos, matches published versio
Compare More Nuanced:Pairwise Alignment Bilinear Network For Few-shot Fine-grained Learning
The recognition ability of human beings is developed in a progressive way.
Usually, children learn to discriminate various objects from coarse to
fine-grained with limited supervision. Inspired by this learning process, we
propose a simple yet effective model for the Few-Shot Fine-Grained (FSFG)
recognition, which tries to tackle the challenging fine-grained recognition
task using meta-learning. The proposed method, named Pairwise Alignment
Bilinear Network (PABN), is an end-to-end deep neural network. Unlike
traditional deep bilinear networks for fine-grained classification, which adopt
the self-bilinear pooling to capture the subtle features of images, the
proposed model uses a novel pairwise bilinear pooling to compare the nuanced
differences between base images and query images for learning a deep distance
metric. In order to match base image features with query image features, we
design feature alignment losses before the proposed pairwise bilinear pooling.
Experiment results on four fine-grained classification datasets and one generic
few-shot dataset demonstrate that the proposed model outperforms both the
state-ofthe-art few-shot fine-grained and general few-shot methods.Comment: ICME 2019 Ora
Exploring the Design and Practice of Ideological and Political Education in the Course of Tunnel Engineering under the Background of New Engineering Discipline: A Case Study of Hope College, Southwest Jiaotong University
Under the background of the new engineering discipline, talent cultivation requires not only intellectual education but also moral education. In response to the main issues concerning ideological and political education in the current new engineering discipline curriculum, this paper focuses on exploring the process of ideological and political construction in tunnel engineering. It highlights the necessity of curriculum-based ideological and political education and the exploration of ideological and political elements. These elements are cleverly integrated into the course design, and the effectiveness of the ideological and political practice in the curriculum is examined through an evaluation of teaching outcomes. The aim is to improve the educational effectiveness of the tunnel engineering construction course and provide valuable insights and references for the ideological and political construction in other engineering disciplines
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