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Systems Engineering Intern | Teledyne Controls

SPS Jobs - 41 min 31 sec ago
US - CA - Thousand Oaks, • Currently enrolled at an accredited college or university - pursuing a Bachelor’s Degree in Engineering maintaining a minimum of 3.0 GPA.• Local candidates only.This is an Internship

Systems Engineering Intern | Teledyne Controls

SPS Jobs - 45 min 31 sec ago
US - CA - El Segundo, Currently enrolled at an accredited college or university - pursuing a Bachelor’s Degree in Engineering maintaining a minimum of 3.0 GPA. Local candidates only. This is a INTERNSHIP&n

Software Engineering Intern | Teledyne Controls

SPS Jobs - 57 min 31 sec ago
US - CA - El Segundo, Must be a registered, full-time student at a College or University focusing on Computer Science or Engineering disciplines; Must maintain a 3.2 or higher grade point average Good interpersonnel, co

Test Engineering Intern | Teledyne Controls

SPS Jobs - 1 hour 6 min ago
US - CA - El Segundo, Currently enrolled at an accredited college or university - pursuing a Bachelor’s Degree in Engineering maintaining a minimum of 3.0 GPA. Must be comfortable using Microsoft Office tools.&nbs

Quality Assurance Intern | Teledyne Controls

SPS Jobs - 1 hour 11 min ago
US - CA - El Segundo, Currently enrolled at an accredited college or university - pursuing a Bachelor’s Degree in Engineering maintaining a minimum of 3.0 GPA. Must be comfortable using Microsoft Office tools.&nbs

Program Analyst Intern | Teledyne Controls

SPS Jobs - 1 hour 19 min ago
US - CA - El Segundo, Currently enrolled at an accredited college or university - pursuing a Bachelor’s Degree in Engineering or Computer Science maintaining a minimum of 3.0 GPA. Must have experience in Microsoft

Environmental Engineering Intern | Teledyne Controls

SPS Jobs - 1 hour 23 min ago
US - CA - El Segundo, Experienced with Microsoft Office products, including Excel, Word, Project, PowerPoint, Outlook, Macros; Microsoft Access is preferred. Currently enrolled at an accredited college or university - p

Ancient Japanese and Finnish ice records yield insights into climate change

Physics Today Daily Edition - 1 hour 38 min ago
National Geographic: Ice observations made in Japan and Finland over the past several centuries are helping modern climate scientists better track climate change. Since at least 1443, Shinto priests have been recording the formation of a distinctive ice ridge on Lake Suwa in the Kino Mountains of central Japan. In Finland, a merchant named Olof Ahlbom started recording the spring ice breakup on the Torne River in 1693, and those observations have been continued by others ever since. By studying the seasonal patterns of ice formation in two such geographically distinct areas over hundreds of years, John Magnuson of the University of Wisconsin–Madison and colleagues have been able to gather important climate data, particularly from before the start of the Industrial Revolution. They note that Suwa has been freezing over progressively later each year and that Torne has been thawing progressively earlier. Also, both areas have been experiencing an increase in the number of extreme warm years. If atmospheric carbon dioxide concentrations and air temperatures continue to rise, the researchers say, Lake Suwa and many other lakes and rivers around the world will fail to freeze over at all.

Civil Engineer Supervisor | Marion County, Oregon

SPS Jobs - 2 hours 16 min ago
US - OR - Salem, EXPERIENCE AND TRAINING  Bachelor's degree with major course work in civil engineering; AND  Four years of related engineering experience, which includes (1) one year of supervisory expe

Japanese satellite <em>Hitomi</em> suffers permanent failure

Physics Today Daily Edition - 2 hours 29 min ago
Nature: On 28 April the Japan Aerospace Exploration Agency announced that it had lost control over its flagship astronomical satellite Hitomi. Despite a successful launch on 17 February, the satellite began experiencing problems within the first few weeks. The source of the difficulty has been traced to its star tracker system, one of several systems on board designed to orient the satellite in space. The star tracker was found to malfunction every time the satellite passed through a certain area over Earth called the South Atlantic Anomaly, where the belts of radiation encircling the planet dip closest to its surface and thus expose satellites to higher-than-normal radiation levels. On 26 March, while Hitomi was passing through that area, a glitch with the star tracker initiated a series of failures with the satellite’s gyroscopes. Hitomi spun out of control, and its solar panels and other components broke off. Although the loss of Hitomi represents a significant blow for x-ray astronomy, before it failed scientists were able to make one important astronomical observation, which could yield enough data for a series of papers.

Communication: An adaptive configuration interaction approach for strongly correlated electrons with tunable accuracy

We introduce a new procedure for iterative selection of determinant spaces capable of describing highly correlated systems. This adaptive configuration interaction (ACI) determines an optimal basis by an iterative procedure in which the determinant space is expanded and coarse grained until self-consistency. Two importance criteria control the selection process and tune the ACI to a user-defined level of accuracy. The ACI is shown to yield potential energy curves of N2 with nearly constant errors, and it predicts singlet-triplet splittings of acenes up to decacene that are in good agreement with the density matrix renormalization group.

Effect of ethanol concentrations on temperature driven structural changes of chymotrypsin inhibitor 2

A series of atomistic molecular dynamics (MD) simulations of a small enzymatic protein Chymotrypsin Inhibitor 2 (CI2) in water-ethanol mixed solutions were carried out to explore the underlying mechanism of ethanol driven conformational changes of the protein. Efforts have been made to probe the influence of ethanol concentrations ranging from 0% to 75% (v/v) at ambient condition (300 K (T1)) and at elevated temperatures (375 K (T2) and 450 K (T3)) to investigate the temperature induced conformational changes of the protein further. Our study showed that the effect of varying ethanol concentrations on protein’s structure is almost insignificant at T1 and T2 temperatures whereas at T3 temperature, partial unfolding of CI2 in 10% ethanol solution followed by full unfolding of the protein at ethanol concentrations above 25% occurs. However, interestingly, at T3 temperature CI2’s native structure was found to be retained in pure water (0% ethanol solution) indicating that the cosolvent ethanol do play an important role in thermal denaturation of CI2. Such observations were quantified in the light of root-mean-square deviations (RMSDs) and radius of gyration. Although higher RMSD values of β-sheet over α-helix indicate complete destruction of the β-structure of CI2 at high ethanol concentrations, the associated time scale showed that the faster melting of α-helix happens over β-sheet. Around 60%-80% of initial native contacts of the protein were found broken with the separation of hydrophobic core consisting eleven residues at ethanol concentrations greater than 25%. This leads protein to expand with the increase in solvent accessible surface area. The interactions between protein and solvent molecules showed that protein’s solvation shell preferred to accommodate ethanol molecules as compared to water thereby excluded water molecules from CI2’s surface. Further, concentration dependent differential self-aggregation behavior of ethanol is likely to regulate the replacement of relatively fast diffused water by low diffused ethanol molecules from protein’s surface during the unfolding process.

Electrical Power Engineer III | KLJ

SPS Jobs - 4 hours 5 min ago
US - FL - Fort Myers, Qualifications A four year degree in electrical power systems engineering or a related field is required Power systems or utility-related experience is required A PE is required Experience level

Strong enhancement of cage effects in water photolysis caused by interatomic Coulombic decay

The impact of the solvent on the photodissociation of embedded molecules has been intensively investigated in the last decades. Collisions of photofragments with the solvating atoms or molecules can change their kinetic energy distribution or even lead to the de-excitation of the dissociating molecule to a bound electronic state quenching the dissociation. In this article we show that this cage effect is strongly enhanced if interatomic Coulombic decay (ICD) of the excited state becomes allowed. Ab initio calculations in H2O–Cl− cluster show that the ultra-fast dissociation of water in the Ãexcited state is strongly quenched by ICD. We found that this very efficient quenching is due to two factors. First, the lifetimes of the à state due to ICD are short ranging between 6 and 30 fs. Second, nuclear dynamics is dominated by the chattering motion of the H atom between O and Cl− allowing ICD to act for longer times. We hope that this work will be an important first step in clarifying the impact of ICD on photodissociation of embedded molecules.

Design and analysis of a MEMS-based bifurcate-shape piezoelectric energy harvester

最新发表论文 - AIP Advances - 4 hours 49 min ago

This paper presents a novel piezoelectric energy harvester, which is a MEMS-based device. This piezoelectric energy harvester uses a bifurcate-shape. The derivation of the mathematical modeling is based on the Euler-Bernoulli beam theory, and the main mechanical and electrical parameters of this energy harvester are analyzed and simulated. The experiment result shows that the maximum output voltage can achieve 3.3V under an acceleration of 1g at 292.11Hz of frequency, and the output power can be up to 0.155mW under the load of 0.4MΩ. The power density is calculated as 496.79μWmm−3. Besides that, it is demonstrated efficiently at output power and voltage and adaptively in practical vibration circumstance. This energy harvester could be used for low-power electronic devices.

Link between hopping models and percolation scaling laws for charge transport in mixtures of small molecules

最新发表论文 - AIP Advances - 4 hours 49 min ago

Mixed host compositions that combine chargetransportmaterials with luminescent dyes offer superior control over exciton formation and chargetransport in organic light emitting devices (OLEDs). Two approaches are typically used to optimize the fraction of chargetransportmaterials in a mixed host composition: either an empirical percolative model, or a hopping transport model. We show that these two commonly-employed models are linked by an analytic expression which relates the localization length to the percolation threshold and critical exponent. The relation is confirmed both numerically and experimentally through measurements of the relative conductivity of Tris(4-carbazoyl-9-ylphenyl)amine (TCTA) :1,3-bis(3,5-dipyrid-3-yl-phenyl)benzene (BmPyPb) mixtures with different concentrations, where the TCTA plays a role as hole conductor and the BmPyPb as hole insulator. The analytic relation may allow the rational design of mixed layers of small molecules for high-performance OLEDs.

A Hamiltonian perturbation theory for the nonlinear Vlasov equation

The nonlinear Vlasov equation contains the full nonlinear dynamics and collective effects of a given Hamiltonian system. The linearized approximation is not valid for a variety of interesting systems, nor is it simple to extend to higher order. It is also well-known that the linearized approximation to the Vlasov equation is invalid for long times, due to its inability to correctly capture fine phase space structures. We derive a perturbation theory for the Vlasov equation based on the underlying Hamiltonian structure of the phase space evolution. We obtain an explicit perturbation series for a dressed Hamiltonian applicable to arbitrary systems whose dynamics can be described by the nonlinear Vlasov equation.

Accumulation rate of bound states of dipoles in graphene

We prove that the bound state energies of the two-dimensional massive Dirac operator with dipole type potentials accumulate with exponential rate at the band edge. In fact we prove a corresponding formula of De Martino et al. [Phys. Rev. Lett. 112(18), 186603 (2014)].

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