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Canamares M.V.,IEM Inc | Feis A.,IEM Inc | Feis A.,University of Florence
Journal of Raman Spectroscopy | Year: 2013

Thiacloprid is a widely used pesticide belonging to the neonicotinoid class, which is characterized by a selective activity against insects and a reduced acute toxicity for humans. The importance of the environmental impact of neonicotinoids is being intensively researched, in order to evaluate the danger they pose for useful insects. Physical methods which allow the characterization of neonicotinoids in diluted aqueous solutions are therefore desirable. We present a study of Raman and surface-enhanced Raman scattering (SERS) spectroscopy on thiacloprid in solid state, in acetone solution, and adsorbed onto silver and gold hydrosols at μM concentration. Density functional theory calculations allow the individualization of the most stable molecular structure, both in gas phase and in solution, and of the corresponding Raman spectra. The vibrational assignments lead to an interpretation of the differences between SERS and ordinary Raman spectra based on the possible interactions between the molecule and the metal surface, the main one involving the iminocyano group. Formation of a charge-transfer complex is suggested by the dependence of the SERS spectra on the laser excitation wavelength. We evaluate the applicability of SERS spectroscopy to the chemical analysis of thiacloprid comparing SERS with current analytical methods. Copyright © 2013 John Wiley & Sons, Ltd. A comprehensive study about the Raman and surface-enhanced Raman scattering features of the widespread insecticide thiacloprid is presented. A complete vibrational assignment and models for the interaction with the metal surface are proposed. Copyright © 2013 John Wiley & Sons, Ltd. Source

He Y.,Clemson University | Chowdhury M.,Clemson University | Pisu P.,Clemson University | Ma Y.,IEM Inc
Transportation Research Part C: Emerging Technologies | Year: 2012

To demonstrate the greater capabilities and benefits achievable with a plug-in hybrid electric vehicle (PHEV), an energy optimization strategy for a power-split drivetrain PHEV, which utilizes a predicted speed profile, is presented. In addition, the paper reports an analysis and evaluation of issues related to real time control implementation for the modeled PHEV system, which include the optimization window sizes and the impact of prediction errors on the energy optimization strategy performance. The optimization time window sizes were identified and validated for different driving cycles under different operating modes and total length of travel. With the identified optimization windows size, improvements in fuel consumption were realized; the highest improvement was for Urban Dynamometer Driving Schedule (UDDS), with a range of improvement of 14-31%, followed by a 1-15% range of improvement for Highway Fuel Economy Driving Schedule (known as HWFET) and a 1-8% range of improvement for US06 (also known as Supplemental Federal Test Procedure). While no correlation was observed between the error rate and the rate of increased fuel consumption, this PHEV system still yielded energy savings with errors in the speed prediction, which is an indication of robustness of this PHEV model. © 2011 Elsevier Ltd. Source

Gaidarov M.K.,Bulgarian Academy of Science | Antonov A.N.,Bulgarian Academy of Science | Sarriguren P.,IEM Inc | De Guerra E.M.,Complutense University of Madrid
Physical Review C - Nuclear Physics | Year: 2012

The symmetry energy, the neutron pressure, and the asymmetric compressibility of deformed neutron-rich even-even nuclei are calculated for the examples of Kr and Sm isotopes within the coherent density fluctuation model using the symmetry energy as a function of density within the Brueckner energy-density functional. The correlation between the thickness of the neutron skin and the characteristics related to the density dependence of the nuclear symmetry energy is investigated for isotopic chains of these nuclei in the framework of the self-consistent Skyrme-Hartree-Fock plus BCS method. Results for an extended chain of Pb isotopes are also presented. A remarkable difference is found in the trend followed by the different isotopic chains: the studied correlations reveal a smoother behavior in the Pb case than in the other cases. We also notice that the neutron skin thickness obtained for 208Pb with the SLy4 force is found to be in a good agreement with recent data. © 2012 American Physical Society. Source

He Y.,Clemson University | Chowdhury M.,Clemson University | Ma Y.,IEM Inc | Pisu P.,Clemson University
Energy Policy | Year: 2012

As the U.S. federal government is seeking useful applications of Vehicle-Infrastructure Integration (VII) and encouraging a greener and more efficient automobile industry, this paper demonstrated a path to meet the national transportation goal via VII. An impact study was conducted in a midsize U.S. metropolitan area on the potential of utilizing VII communication in Hybrid Electric Vehicle (HEV) operations by simulating a VII-enabled vehicle framework for both conventional HEV and Plug-in Hybrid Electric Vehicles (PHEV). The data collection and communication capability of the VII system allowed the prediction of speed profiles at the vehicle level with an average error rate of 13.2%. With the prediction, at the individual vehicle level, VII technology allowed PHEV and HEV to achieve additional benefits with an approximately 3% decrease in total energy consumption and emission. At the network level, the benefit-cost analysis indicated that the benefit-cost ratios for PHEV and HEV of the VII vehicle network exceed one at the fleet penetration rate of 20% and 30%, respectively. Our findings encourage to support public and private investments in VII infrastructure and its integration with HEV and PHEV in order to reap the increased energy savings from these vehicles. © 2011 Elsevier Ltd. Source

News Article | October 30, 2012
Site: www.wired.com

Laying out four Benjamins to replace an accessory that comes for free in the box with your phone seems, I don’t know, totally and completely stupid. But after listening to my favorite music through this in-ear headset for the past month, I can confidently say I’d drop $400 of my own cash on a pair without remorse. The only tear I’d shed would be for all my other in-ear headphones, which would go unused forevermore. The headphones in question: Logitech’s UE 900. They’re the new flagship audiophile earphones from the venerable Ultimate Ears brand, and they’re just as awesome and perfect and beautiful-sounding as you’d expect from a $400 headset. Ultimate Ears became well known for making custom in-ear monitors (IEMs) and noise-attenuating ear plugs for musicians to wear on stage. Professional IEMs usually require you to have custom molds made of your ears, and the results are super-fancy, but expensive. Later, with the iPod explosion, the company found a way to distill the essentials of its pro-level in-ear design into a non-custom consumer model. Its UE-5c and TripleFi 10 models basically defined the early consumer IEM market, and they are still some of the most well-regarded IEMs among audiophile consumers. (I had a pair of TF10s that I recently retired from service after several years.) Now, Ultimate Ears — which has since been acquired by accessories giant Logitech — has worked up a new design for its latest flagship in-ear. Like previous in-ear monitors, this one takes many cues from the pro-level models before it. If you want a pair of pro-level IEMs, but you don’t want to pay out the nose for the privilege, this will get you remarkably close for “only” $400. The UE 900 uses a unique four-driver design: two balanced armature drivers for the low-end, one for the mids and one for the highs. The result is some truly glorious sound, supremely rich from one end of the audio spectrum to the other. The bass is heavy and direct. Mid-range frequencies are perfectly represented, and the chiming highs are only slightly tempered at the very, very top end. The new flagship audiophile earphones from Ultimate Ears are just as awesome and perfect and beautiful-sounding as you'd expect from a $400 headset. I got so carried away during the first session, I kicked back on my bed and didn’t get up again until I had completely run down the battery on my iPhone. This level of clarity and drama of course has a lot to do with the quality of the drivers, but it has just as much to do with the fit. Logitech ships the UE 900s with eight in-ear options for obtaining the best seal: silicone tips ranging from size large all the way down to size XXS, as well as three different sizes of Comply foam tips. The in-ear fit these require is not for everyone. And just putting the things in properly takes some practice. Like other high-end IEMs, the first few inches of the cable extending out of the ear pieces is made of “memory wire,” a coating that stiffens the cable and lets you bend it into different shapes. You actually position the UE 900s upside-down, so the cables leave the bodies through the top. Holding the body, you wrap the stiff part of the cable over the top of your ear, then tug it snug and push the rubber tip into your ear canal. This configuration is weird if you’re not used to it, and as a lifelong glasses-wearer, I’d rather not have to futz with memory wire. But the UEs have the most comfortable over-the-ear cable system I’ve encountered yet — certainly preferable to the rigid plastic cable guides you get with some IEMs. When properly fitted, Logitech says the UE 900s will give you a full 26db of noise isolation. When properly fitted, Logitech says the UE 900s will give you a full 26db of noise isolation. I trust this claim — I listened on city buses, while walking the streets at rush hour, and while at my desk in the bustling office, and I have no complaints about the level of isolation. The totally immersive experience is enhanced by the braided cabling, which produce only a minimal amount of noticeable noise as it rubs and bumps against your clothes. Because the cable ends run down the sides of your neck, you can wear the main cable across the front of your shirt, or down your back, which is better for runners. An optional collar clip helps, too, by keeping the cable tucked to whatever piece of clothing works best. I listened to the UE 900s through a couple of headphone amps — a Total BitHead and an Apex Butte — and they were of course even more impressive and huge-sounding. But they were primarily made for mobile use, and they are sensitive enough that you won’t need an amp. Just plug them right into your phone. The default cable is bright blue, as seen on other UE gear, and has a three-button remote that works with iPhones and iPods (though it acts janky on Android phones, a troubling trend I’ve noticed on almost every headset I’ve tested this year). Each pair ships with an alternate, remote-free black cable, and they’re easy to swap out. There are a lot of things you could spend $400 on. A world series ticket, a couple of car payments, the tasting menu for two at Alinea (sans wine pairing). But if you love hearing music beautifully represented without distraction, and you crave that level of audio perfection all the time, everywhere, Logitech’s newest Ultimate Ears are some of the best mobile headphones you can buy. Your friends or loved ones may pick on you for spending so much. But if they do, just shove these in your ears and go to your happy place.

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