Stadler F.J.,Catholic University of Louvain |
Stadler F.J.,Chonbuk National University |
Rajan M.,TU Eindhoven |
Agarwal U.S.,TU Eindhoven |
And 6 more authors.
Rheologica Acta | Year: 2011
We investigate the linear and non-linear rheological behavior in shear of a concentrated solution of "dumbbell" polystyrene with long linear backbone and dense short brushes at both ends and compare it with corresponding linear polymers. This type of dumbbells has never been rheologically characterized before. In linear viscoelasticity, the dumbbell polymers show significant differences with conventional linear polymers. In particular, the reptation relaxation of the dumbbell is strongly slowed down. Furthermore, the addition of the side chains increases the friction so that the dumbbell lies above the η0 vs. number of entanglements relation of linear samples. Transient shear rheology experiments on weakly entangled solutions show a retardation of the chain stretch relaxation of the dumbbell by a factor 2. 5 vs. a linear polymer with the same Rouse time. Additionally, a second peak in the transient viscosity is observed at high shear rates. © 2011 Springer-Verlag.
Anand K.A.,Cochin University of Science and Technology |
Jose T.S.,Cochin University of Science and Technology |
Agarwal U.S.,Reliance Technology Ventures |
Sreekumar T.V.,Reliance Technology Ventures |
And 2 more authors.
International Journal of Polymeric Materials and Polymeric Biomaterials | Year: 2010
Poly(ethylene terephthalate)-single-walled carbon nanotube (PET-SWNT) nanocomposite fibers have been prepared through melt spinning and drawing. While acting as effective nucleating agents for PET melt crystallization, SWNTs also provide significant reinforcement to PET fibers. For example, the tenacity and initial modulus of the composite fiber with 1wt% SWNTs were, respectively, 1.8 times and 3.2 times higher as compared to those of the pristine PET fiber prepared under identical conditions. When the draw ratio was increased, tenacity and modulus of the fibers increased, indicating that drawing induced orientation of the polymer molecules and SWNTs. Thermal stability of the fibers was not significantly affected by the presence of SWNTs at low concentrations.
Sharma S.K.,Indian Central Salt and Marine Chemicals Research Institute |
Sharma S.K.,University of Bath |
Sidhpuria K.B.,Indian Central Salt and Marine Chemicals Research Institute |
Sidhpuria K.B.,University of Aveiro |
And 2 more authors.
Journal of Molecular Catalysis A: Chemical | Year: 2011
Ruthenium containing hydrotalcite (Ru-HT) was synthesized by partial substitution of Mg2+ or Al3+ cations by ruthenium metal in octahedral layers of hydrotalcite and used as a catalyst for hydrogenation of benzene to cyclohexane. Effect of catalyst amount, reaction temperature, partial pressure of hydrogen and volume of solvent on conversion of benzene was studied in detail. Higher conversion of benzene in lower reaction time was observed in lower volume of solvent. Complete conversion of benzene with 100% selectivity of cyclohexane was observed at 120 °C reaction temperature and 60 atm partial pressure of H2 in 2 h reaction time. Presence of moisture in the reaction mixture showed negligible effect on catalytic activity of Ru-HT, however, activity decreased significantly on increasing the sulfur concentration. Catalyst was recycled upto four times without significant loss in its activity. No conversion of benzene was observed in case of pristine hydrotalcite (without ruthenium) as a catalyst. © 2010 Elsevier B.V.
Gurudatt K.,Reliance Technology Ventures |
Nadkarni V.M.,Reliance Technology Ventures |
Khilar K.C.,Indian Institute of Technology Bombay
Journal of the Textile Institute | Year: 2010
Gravimetric absorption test system (GATS) is used to measure the absorption capacity, absorption rate and drying rate of knit hoses, prepared from different fibres. The fibres studied are cotton, polyester and variety of modified polyesters. The study has shown that desorption or drying rate is at least two orders of magnitude lower than absorption rate. This finding implies that drying is the limiting process in moisture management. Further experiments on knit fabrics made from polyester and cotton, show that the drying rates are independent of fibre type in the constant-rate period, while the drying rates in the falling-rate period are dependent on fibre type. Subsequently, it is shown on the polyester fabric that drying rate in the falling-rate period depends on water concentration. Based on this understanding, an approach for enhancing drying rate in the falling-rate period is defined. The approach is demonstrated on knit hoses prepared from cotton and polyester yarns in alternating stripe form. The drying rate in the falling-rate period is found to be higher in the polyester-cotton stripe knit hose. A hypothesis for the observed enhancement in drying rate by wicking is put forth in terms of the internal movement of water from polyester to cotton portion. Experimentally, it is shown that 16% improvement in drying time is achieved in the case of the polyester-cotton stripe samples. Further, indications of internal water movement from polyester to cotton portion have been obtained by tracking the surface temperatures of the knit hoses during drying by infrared (IR) thermography. © 2010 The Textile Institute.
News Article | June 11, 2008
Airtel and Vodafone (NYSE: VOD) will launch the iPhone 3G in India this year. Airtel President and CEO Manoj Kohli is quoted by HT stating the device will available by mid-October. Vodafone however has refused to comment. Both the operators haven’t shared pricing details. Apple’s revised pricing has given my previous post a shining black eye. We had earlier predicted the average pricing of the 2G phones to be Rs 21k (8GB) and around 25k (16GB). The 3G versions will be Rs 8k (8GB) and Rs 12k (16GB), although subject to a 2 year contract in the States. If 3G policy shapes up by year-end and the 3iPhone is able to land at a similar price point, it could turn out to be a great entry buy and sell for both consumers and operators. Besides, being location aware would help operators like RComm (Reliance Technology Ventures has funded Whrrl, the first iPhone app development venture to be funded) to position it based on local services rather than only price cuts. Meanwhile, after having paid twice the amount for a fatter 16GB 2G version, buyers remorse has robbed me of life, appetite and sleep. Thankfully, there is comfort in numbers, I am not the only one to have bitten that Apple (NSDQ: AAPL).
News Article | July 24, 2008
Intel (NSDQ: INTC) Capital, the venture capital arm of chipmaker Intel, has announced that it would invest $17 million into three Indian companies – which includes travel portal Yatra.com, events-oriented social networking portal BuzzInTown.com, and Emnet Samsara Media Pvt. Ltd., an out-of-home advertising firm focusing on the Indian public transportation market. How much has gone into each company is not not known yet. Yatra.com CEO and founder Dhruv Shringi told VC Circle that this is the third round of investment in the company. He, however, declined to reveal the quantum of the investment. The first two rounds of investments were done by Norwest Venture Partners, Reliance Technology Ventures and TV18 Group. In the case of BuzzInTown, a community oriented site which helps users discover local events in major Indian cities, this could be Series A. Emnet Samsara Media Pvt. Ltd, an OOH media company targeted at public transportation company, joins a list of OOH media companies such as Laqshya, LiveMedia, and DSN that got funded by venture capital firms. Since starting in India in 1998, Intel Capital has invested in approximately 50 companies across eight cities. This story was provided by our content partner VCCircle
News Article | September 25, 2008
Reliance Technology Ventures and Norwest Venture Partners India have invested an undisclosed amount in Mumbai-based Suvidhaa Infoserve Pvt Ltd, which has a technology that helps people make daily transactions such as railway ticketing, mobile recharge, air ticketing, insurance payment, bill payment, bus ticketing, movie ticketing and so on. The company has already installed its devices in some 4,000 kirana stores. Suvidhaa’s proprietary technology platform integrates these kirana stores to the various services providers’ systems. The company is backed by the Shapoorji Pallonji group and calls itself a services commerce (S-Commerce) firm. Suvidhaa
News Article | April 21, 2009
Fixed-wireless convergence company Stoke has raised $15 million in a fourth round of funding from Reliance Technology Ventures Limited, Sequoia Capital, Kleiner Perkins Caufield & Byers, and Japanese networking company Net One Systems, reports TechCrunch. The company has raised $65 million in total. Its hardware is aimed at wireless carriers, which are increasingly trying to figure out how to better manage the growing bandwidth pressures on their networks as more people download apps, videos and songs on their mobile phones. Stoke
News Article | April 20, 2009
Mobile broadband network developer Stoke has received $15 million in Series D funding from Reliance Technology Ventures Limited, Sequoia Capital, Kleiner Perkins Caufield & Byers, and Japanese networking company Net One Systems, bringing the telecom network startup’s total funding to $65 million. Stoke raised $20 million in Series C funding in 2007 (led by DAG Ventures), $19.8 million in Series B funding in 2005, and $10 million in Series A funding. As people are using their mobile phones to download applications, view movies, and listen to music, mobile data carriers need to provide greater bandwidth to support mobile phone usage. Stoke’s hardware provides mobile carriers the technology to let phones access different wireless networks including 3G, GSM, CDMA, Wi-Fi and WiMax and converges wireless coverage to help carriers cope with massive increments in web traffic. For example, Stoke’s technology lets phones seamlessly detect different networks and will automatically enable phones to switch to available networks based on location and availability. Stoke says the new funds will be used to support continuing partnerships with with mobile carriers.