1,088 research outputs found
sj-docx-1-trr-10.1177_03611981231152467 – Supplemental material for Impact of Inconsistent Behavior of Drivers on Estimation of Critical Gap at Multi-Lane Roundabouts
No full textSupplemental material, sj-docx-1-trr-10.1177_03611981231152467 for Impact of Inconsistent Behavior of Drivers on Estimation of Critical Gap at Multi-Lane Roundabouts by Chirag Bhasin and Pardeep Kumar in Transportation Research Record</p
Joining of Ceramics and Ceramic Matrix Composites (CMC) for Aerospace and Energy Applications
No full textSiC-based ceramics and composites (SiC, C/SiC & SiC/SiC) are more and more extensively used as advanced materials for aerospace and energy applications. Existing applications are expanding continuously and require advanced materials, design and joining technologies.
The objective of this thesis was to join SiC-based ceramic matrix composites (CMC), ceramics (SiC, Mullite, Alumina) and SiC-based ceramic foams for aerospace and energy applications.
The research was aimed to develop strong, oxidation resistant and high temperature stable joints.
A novel joining technique defined “RM-Wrap” (RM=Mo, Nb, Ta, W Refractory Metals) has been developed within this thesis. The developed technique is a novel brazing technology named RM-Wrap after the metal used as a wrap to contain one or more silicon foils (e.g. Mo-Wrap when a Mo wrap is used to contain a Si foil).
It is a pressure-less joining technology performed at 1450 oC, under an inert environment (Argon flow).
Joining materials are in-situ formed composites made of refractory metals silicides (MoSi2, NbSi2, TaSi2 and WSi2) embedded in a silicon matrix.
RM-Wrap is a highly tailorable joining technique: the quantity of each phase can be modified and more than one refractory metals can be used together. RM-Wrap has been very effective in joining both coated and uncoated CMC, porous and non-porous materials: ceramics (oxide and non-oxide), CMC (SiC-based) and highly porous substrates (SiC foams) having porosity higher than 80% have been soundly joined.
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The joint morphology (interphase and interface) and elemental composition of the joining material was investigated in detail using FESEM and EDS which showed uniform, continuous and crack free joints. XRD investigation confirms the formation of metal silicides. Oxidation resistance of joints was carried out at 1100 oC for 30 minutes (for CMC joints) and 6 hours (for monolithic ceramic joints) in the air; prior and post oxidation examination of joint morphology showed no morphological change and joints remained firmly joined.
Sandwich structures have been developed by Mo-wrap joining two C/SiC as “skins” to the “core” SiC foam. Sandwich structures were tested for thermal shock resistance from RT to 1100 oC in the air for 2 minutes. Three cycles on a single sandwich structure were performed, which remained joined and the joining material composition unchanged.
Joints were mechanically tested in three different modes (i) compression, (ii) tensile and (iii) torsion. Joint strength was higher than the interlaminar shear strength of composites as the fracture was always observed in composites.
In case of monolithic ceramic (SiC) a mixed failure (cohesive and adhesive) was found, which suggest that the joint strength is comparable to ceramic one.
Micro- and nanoindentation tests were also carried out on joining materials
Pressure-less joining of C/SiC and SiC/SiC by a MoSi2/Si composite
No full textA MoSi2/Si composite obtained in situ by reaction of silicon and molybdenum at 1450°C in Ar flow is proposed as pressure-less joining material for C/SiC and SiC/SiC composites. A new “Mo-wrap” technique was developed to form the joining material and to control silicon infiltration in porous composites. MoSi2/Si composite joining material infiltration inside coated and uncoated C/SiC and SiC/SiC composites, as well as its microstructure and interfacial reactions were studied. Preliminary mechanical strength of joints was tested at room temperature and after aging at service temperatures, resulting in interlaminar failure of the composites in most cases
"Re-wrap” method (Refractory metals Re= Mo, Nb, Ta and W) for joining of ceramics and CMC
No full textJoining of C/SiC for aerospace applications
No full textTo join C/SiC to C/SiC with a new, pressure-less composite joining material and technique, for high performance application
Joining of C/SiC Ceramic Composites to themselves and to Ti-6Al-4V for aerospace applications
No full textsj-docx-1-wmr-10.1177_0734242X231219627 – Supplemental material for Predicting opinion using deep learning: From burning to sustainable management of organic waste in Indian State of Punjab
No full textSupplemental material, sj-docx-1-wmr-10.1177_0734242X231219627 for Predicting opinion using deep learning: From burning to sustainable management of organic waste in Indian State of Punjab by Amandeep Singh, Rupasi Tiwari, Pardeep Singh Nagra, Pratikshya Panda, Gurpreet Kour, Bilawal Singh, Pranav Kumar and Triveni Dutt in Waste Management & Research</p
GeoCovaxTweets: COVID-19 Vaccines and Vaccination-specific Global Geotagged Twitter Conversations
No full textGeoCovaxTweets: Geotagged Covid-19 Vaccine Conversations on Twitter
The following metadata is available for tweets in GeoCpvaxTweets:
id: tweet identifier
created_at: DateTime when the tweet was created
author_id: the unique identifier of the author who created the tweet
author. location: profile address of the author who created the tweet
source: application/utility used for creating the tweet
entities.hashtags: Hashtags used for creating the tweets
geo.country_code: country code, NULL if the tweet is not geotagged
author. verified: verification status of the author who created the tweet
author.public_metrics.followers_count: followers count of the author
state: state name where the tweet is created
To compare upper extremity strength, core and respiratory endurance between post-COVID 19 and healthy population
No full textBACKGROUND: Covid-19 plays a crucial role in affecting the world ‘s population. The objective of the study is to compare the limb strength,core strength, and respiratory endurance of the post-covid-19 population and the healthy population. The post-covid-19 sign and symptoms that develop after the infection can decrease daily living activity Like decreased strength, and endurance of the body function. PURPOSE: To compare the limb strength, core strength, and respiratory endurance of the post-covid-19 population and healthy populatio
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