Controlled intermittent interfacial bond concept for composite materials

Concept will enhance fracture resistance of high-strength filamentary composite without degrading its tensile strength or elastic modulus. Concept provides more economical composite systems, tailored for specific applications, and composite materials with mechanical properties, such as tensile strength, fracture strain, and fracture toughness, that can be optimized

Application of Solar Water Heaters for Industrial Use

Solar water heating is a technology that is mainly used for domestic water heating in residential homes. In most applications, the idea is to make a home “off the grid” in that there is no requirement for outside infrastructure or need for energy utility to provide power to this home. This falls in line with the trend of “going green” in an effort to reduce energy use, increase efficiency, or reduce emissions and other harmful byproducts. This technology can be adapted to reduce the energy costs of industrial manufacturing plants. By eliminating the need for certain sections of a process or system, energy can be reduced by utilizing technology that takes advantage of the renewable energy sources. The radiation of the sun is a source of energy largely underutilized in the industrial level. While solar panels may be used to generate electrical energy, processes where fuel is needed to heat material in bulk is still done by fossil fuels such as natural gas or coal. Solar water heating takes advantage of the ever-present nature of the sun in order to heat water that would otherwise require electricity or natural gas to heat, thereby reducing the production costs by removing portions of energy requirements in the manufacturing process. This thesis serves to test a design for a solar water heating system geared specifically to an industrial application by reducing the energy requirement of a boiler preheater. The design will show the ease of the application of solar water heating into steam generation. The design will also show the ease of renewable energy modeling programs and their viability in predicting the savings of systems

Highly-tunable formation of nitrogen-vacancy centers via ion implantation

We demonstrate highly-tunable formation of nitrogen-vacancy (NV) centers using 20 keV 15N+ ion implantation through arrays of high-resolution apertures fabricated with electron beam lithography. By varying the aperture diameters from 80 to 240 nm, as well as the average ion fluences from 5 x 10^10 to 2 x 10^11 ions/cm^2, we can control the number of ions per aperture. We analyze the photoluminescence on multiple sites with different implantation parameters and obtain ion-to-NV conversion yields of 6 to 7%, consistent across all ion fluences. The implanted NV centers have spin dephasing times T2* ~ 3 microseconds, comparable to naturally occurring NV centers in high purity diamond with natural abundance 13C. With this technique, we can deterministically control the population distribution of NV centers in each aperture, allowing for the study of single or coupled NV centers and their integration into photonic structures.Comment: Related papers at http://pettagroup.princeton.ed

Nov pristup dvojezičnoj leksikografiji pomoću semantike okvira

This paper presents the results of work carried out with Charles J. Fillmore, University of California, Berkeley. I describe the way in which one particular theoretical framework (Fillmore\u27s \u27frame semantics\u27, combined with \u27construction grammar\u27, the work of Fillmore and his colleague Paul Kay) may be applied in standard bilingual lexicography. This approach helps lexicographers to prioritize information from corpus data, so that the essential semantic and grammatical facts are recorded for use in the dictionary entry. Taking this further, I propose a new graphic method for showing equivalences and divergences between source and target languages in a bilingual dictionary. My practical examples use the English verb crawl and the French verb ramper.U ovom članku iznosim rezultate svoga rada s Charlesom J. Fillmoreom (University of California Berkeley). Opisuje se način na koji se konkretni teorijski model (Fillmoreova semantika okvira u kombinaciji s konstrukcijskom gramatikom, proizašlom iz Fillmoreove suradnje s Paulom Kayem) može primijeniti u standardnoj dvojezičnoj leksikografiji. Takav pristup pomaže leksikografima odrediti kojim informacijama iz korpusnih podataka valja dati prednost kako bi bitne semantičke i gramatičke činjenice bile zabilježene i uvrštene u rječnički članak. U daljnjoj razradi predlažem novu grafičku metodu za predočavanje ekvivalencija i divergencija između izvornoga i ciljnoga jezika u dvojezičnom rječniku. Konkretni primjeri prikazuju obradu engleskoga glagola \u27crawl\u27 i francuskoga glagola \u27ramper\u27

Brane world models need low string scale

Models with large extra dimensions offer the possibility of the Planck scale being of order the electroweak scale, thus alleviating the gauge hierarchy problem. We show that these models suffer from a breakdown of unitarity at around three quarters of the low effective Planck scale. An obvious candidate to fix the unitarity problem is string theory. We therefore argue that it is necessary for the string scale to appear below the effective Planck scale and that the first signature of such models would be string resonances. We further translate experimental bounds on the string scale into bounds on the effective Planck scale

Strong impact of light induced conical intersections on the spectrum of diatomic molecules

We show that dressing of diatomic molecules by running laser waves gives rise to conical intersections (CIs). Due to presence of such CIs, the rovibronic molecular motions are strongly coupled. A pronounced impact of the CI on the spectrum of $Na_2$ molecule is demonstrated via numerical calculation for weak and moderate laser intensity, and an experiment is suggested on this basis. The position of the light induced CI and the strength of its non-adiabatic couplings can be chosen by changing the frequency and intensity of the used running laser wave. This offers new possibilities to control the photo-induced rovibronic molecular dynamics.Comment: 4 pages, 7 figure

Electrochemical reduction of carbamazepine in ethanol and water solutions using a glassy carbon electrode

The electrochemical reduction of carbamazepine in ethanol and water using a glassy carbon electrode has been studied. In all experimental conditions of scan rate and concentration of carbamazepine an irreversible cathodic wave was observed by cyclic voltammetry (CV). Electrochemical parameters and a plausible EqC mechanism have been reported from the electrochemical measurements and digital simulation. The values of thermodynamic E1/2 were correlated with solvent polarity parameters that it can be interesting for biological, pharmaceutical and forensic purposes. Limits of Detection (LOD) for DPV are 1.1 and 9.0 g/mL (4.65x10-6 and 3.81x10-5 M) in ethanol and water, respectively. The precision and recoveries obtained for tablets and plasma samples showed that the method could be successfully used for analysis

Non-locality in quantum field theory due to general relativity

We show that general relativity coupled to a quantum field theory generically leads to non-local effects in the matter sector. These non-local effects can be described by non-local higher dimensional operators which remarkably have an approximate shift symmetry. When applied to inflationary models, our results imply that small non-Gaussianities are a generic feature of models based on general relativity coupled to matter fields. However, these effects are too small to be observable in the cosmic microwave background

Local Behavior of the First-Order Gradient Correction to the Thomas-Fermi Kinetic Energy Functional

The first order gradient correction to the Thomas-Fermi functional, proposed by Haq, Chattaraj and Deb (Chem. Phys. Lett. vol. 81, 8031, 1984) has been studied by evaluating both the total kinetic energy and the local kinetic energy density. For testing the kinetic energy density we evaluate its deviation from an exact result through a quality factor, a parameter that reflects the quality of the functionals in a better way than their relative errors. The study is performed on two different systems: light atoms (up to Z=18) and a noninteracting model of fermions confined in a Coulombic-type potential. It is found than this approximation gives very low relative errors and a better local behavior than any of the usual generalized gradient approximation semilocal kinetic density functionals.Comment: 7 pages, 2 tables, 4 figure