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Number of results: 6
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Abstract

Conventional fuels are the primary source of pollution. Switching towards clean energy becomes increasingly necessary for sustainable development. Electric vehicles are the most suitable alternative for the future of the automobile industry. The battery, being the power source, is the critical element of electric vehicles. However, its charging and discharging rates have always been a question. The discharge rate depends upon various factors such as vehicle load, temperature gradient, surface inclination, terrain, tyre pressure, and vehicle speed. In this work, a 20 Ah, 13S-8P configured lithium-ion battery, developed specifically for a supermileage custom vehicle, is used for experimentation. The abovementioned factors have been analyzed to check the vehicle’s overall performance in different operating conditions, and their effects have been investigated against the battery’s discharge rate. It has been observed that the discharge rate remains unaffected by the considered temperature difference. However, overheating the battery results in thermal runaway, damaging and reducing its life. Increasing the number of brakes to 15, the impact on the discharge rate is marginal; however, if the number of brakes increases beyond 21, a doubling trend in voltage drops was observed. Thus, a smoother drive at a slow-varying velocity is preferred. Experiments for different load conditions and varying terrains show a rise in discharge with increasing load, low discharge for concrete, and the largest discharge for rocky terrain.
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Authors and Affiliations

Shreya Dhawan
1
Aanchal Sabharwal
2
Rupali Prasad
2
Shreya Shreya
2
Aarushi Gupta
2
Yusuf Parvez
3

  1. Duke University, Durham, USA
  2. Indira Gandhi Delhi Technical University for Women, Mechanical and Automation Engineering, New Delhi, India
  3. Maulana Azad National Urdu University, Mechanical Engineering, Cuttack, Odisha, India
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Abstract

Many granitic intrusions display evidence of magma mixing processes. The interaction of melts of contrasting composition may play a significant role during their generation and evolution. The Strzegom-Sobótka massif (SSM), located in the Sudetes (SW Poland) in the north-eastern part of the Bohemian Massif of the Central European Variscides, exhibits significant evidence of magma mingling on the macro- and micro-scales. The massif is a composite intrusion, with four main varieties: hornblende-biotite granite (with negligible amount of hornblende) and biotite granite in the western part, and two-mica granite and biotite granodiorite in the eastern part. Field evidence for magma mingling is easily found in the biotite granodiorite, where dark enclaves with tonalitic composition occur. Enclaves range from a few centimeters to half a meter in size, and from ellipsoidal to rounded in shape. They occur individually and in homogeneous swarms. The mixing textures in the enclaves include fine-grained texture, acicular apatite, rounded plagioclase xenocrysts, ocellar quartz and blade-shaped biotite. The most interesting feature of the enclaves is the presence of numerous monazite-(Ce) crystals, including unusually large crystals (up to 500 μm) which have grown close to the boundaries between granodiorite and enclaves. The crystallization of numerous monazite grains may therefore be another, previously undescribed, form of textural evidence for interaction between two contrasting magmas. The textures and microtextures may indicate that the enclaves represent globules of hybrid magma formed by mingling with a more felsic host melt. Chemical dating of the monazite yielded an age of 297±11 Ma.

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Authors and Affiliations

Justyna Domańska-Siuda
Bogusław Bagiński
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Abstract

The general standards and guidelines recommendations for PCC suggest alternating conditions of curing: starting with wet conditions for effective hydration of Portland cement followed by air-dry conditions for polymer hardening. The often accepted curing regime of PCC covers 5 days of wet curing and then the air-dry curing but it is not the optimum one. The aim of the investigation was to find the best scenario for PCC with two types of polymer modifiers: two-component epoxy resin and water dispersion of polyacrylates. The following exploitation properties were accepted as the criteria of evaluation of PCC curing effectiveness: compressive strength, tensile splitting strength, surface tensile strength (by pull-off method), wear resistance, water penetration under pressure and resistance to carbonation. The optimum time of PCC wet curing is possibly between 7 and 14 days, however, it have to be verified experimentally for specific PCC composition.

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Authors and Affiliations

P. Woyciechowski
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Abstract

Although the terrestrial marginal zones of some glaciers on Spitsbergen are relatively well described, we are largely ignorant about the morphology of their submarine forefields. Initial reconnaissance of the forefields of the Aavatsmark and Dahl glaciers in the Kaffiøyra region and soundings made in that of the Hans Glacier (southern Spitsbergen ) indicate the occurrence of sea-floor push-moraines which can be as much as 3 m high. Their lateral separation is considered to denote annual recession rates. They appear to result from cyclical annual advances of ice-cliffs during winters when the deposits are risen up at the contact of the ice with the sea-floor. The development of the major forms may be related to surge. There is some evidence that certain elements in the sea-bed morphology date from the Little Ice Age (LIA).

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Authors and Affiliations

Marek Grześ
Michał Król
Ireneusz Sobota
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Abstract

The paper presents a catalogue, with description, detailed map location and references to first publications, of new place names introduced mainly during the Polish Geodynamic Expeditions to West Antarctica, 1984-1991. In the South Shetland Islands, new place names were introduced in parts of King George Island and Deception Island (Some new names for Admiralty Bay, King George Island and Penguin Island, introduced prior to 1984 but not yet formally described, are also included here). In Antarctic Peninsula, new place names have been introduced at Hope Bay (Trinity Peninsula), Arctowski Peninsula-Andvord Bay (Danco Coast/Gerlache Strait) and Paradise Harbour (Danco Coast).

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Authors and Affiliations

Krzysztof Birkenmajer
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Abstract

The aim of this paper is to analyse the welfare consequences of the processes of liberalisation of trade between asymmetric states in terms of the various size sand effectiveness of their economies and the type of international exchange. These characteristics ultimately define the distribution of benefits from the liberalisation of international trade. When it is inter-industry or vertical intra-industry and barriers in trade are smaller than the difference in the effectiveness of the economies, the trade liberalisation undoubtedly contributes to improved social welfare, regardless of the level of effectiveness and the size of the economy. In the situation, however, of horizontal intra-industry trade, changes in the welfares of asymmetric countries, caused by their progressing trade liberalisation, depend on the sizes and effectiveness of their economies. The welfare of society in either a very big and ineffective or in a small and very ineffective country could even decrease in such a situation. This is the case when the increase in consumers’ surplus is not sufficient to compensate for the decreasing profits of firms.

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Authors and Affiliations

Krzysztof Kosiec

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