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Temperature increase by AuNPs irradiated with laser, was evaluated to determine the differences generated useful in photonic plasmon photothermal therapy or multiphoton plasmon photothermal therapy respectively. AuNPs were synthesized by the Turkevitch method and characterized by spectroscopic techniques. The AuNPs were irradiated by a Nd:YAG laser for 210 s, with 532 and 1064 nm wavelength at 5, 10 and 15 Hz pulse repetition rate frequency. Temperature recording was carried out every second by a type-K thermocouple bounded to an ARDUINO® card. AuNPs showed spherical shape, size of 20.7+0.2 nm and a maximum absorption peak of 520.16+0.93 nm. AuNPs irradiated at 1064 nm wavelength showed the greater temperature increase. [ABSTRACT FROM AUTHOR]

Microwave ovens produce 2450 MHz electromagnetic radiation. These appliances are shielded to prevent radiation leaks, although a small part goes outside. With a Schottky diode, a multimeter and a metal screen, the wave nature of this radiation can be experimentally verified and its wavelength measured. [ABSTRACT FROM AUTHOR]

This study presents the design of a control strategy for alternating current (AC) programmable electronic loads (PEL) applied to test scenarios in power microgrids. The control strategy is based on hysteresis current control (HCC) for the operation of a three-phase inverter to emulate load profiles. The PEL's design is divided into power and control stages to identify operating principles. The topology used is a three-phase four-wire AC PEL, using star and split DC bus connections. The DC link voltage is controlled through a Buck converter based on the power balance of the system. The PEL has been designed to operate in constant power, impedance, and current modes. It is concluded that PEL simulations function properly, representing power stage wavelengths and control signs according to theory. [ABSTRACT FROM AUTHOR]

The article describes the meteorological phenomenon known as Alpenglühen or alpine glow, which refers to the coloring that the mountains acquire before and after sunrise or sunset. During sunset, the color of the sky changes due to Rayleigh scattering and Mie scattering, resulting in the loss of shorter wavelengths and the predominance of yellow and red colors. Additionally, the article mentions anticrepuscular colors, such as the Earth's shadow and the Belt of Venus, which are observed on the eastern horizon after sunset. The article describes two atmospheric phenomena related to the evening light in the mountains: the "Belt of Venus" and the "Alpenglühen". Both phenomena are more visible on cold winter days and in snowy mountains or vertically developing clouds. [Extracted from the article]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The phytosanitary status of Kikuyu grass (Cechrus clandestinum (Hochst ex Chiov)) was studied using a multispectral imaging sensor carried by a drone. Reflectance in the red (R), green (G), blue (B), red-edge (RE), and near infrared (NIR) wavelengths was recorded for 109 sampling points. Wavelengths were related to the degree of damage caused by pests, determined in the field. R, G, B, and RE wavelengths were moderately correlated with the degree of disease in the leaves, with 0.63, 0.51, 0.51 and 0.50 coefficients, respectively, while near infrared wavelength presented a low positive correlation (r = 0.14). In total, 25 generalized linear models were evaluated, where the model y = (41.33 * R) + (1.38 * NIR), with 0.69 deviance, resulted in the highest parsimony model. In addition, is an easy model to apply because it uses two bands only. [ABSTRACT FROM AUTHOR]

Practical teaching experiments on optical Doppler effect are not a simple task, not only by the design but also because the experiment itself have many issues. The main problem is to produce a smooth movement of the light source, for little imperfections, of the order of the wavelength, result in important noises in the final measurements. Using a rotating mirror in which the incident beam is reflected in both the receding and the advancing parts of its surface, allows to minimize noise problems as well as mechanical deviations. The laboratory practice described in this paper can be constructed using low cost parts that are usually found in student laboratories. We also propose some questions and problems to help the teaching to work out this matter. [ABSTRACT FROM AUTHOR]

Light changes its path and the polarization state if it interacts with a medium whose particles are much smaller than its wavelength. The phenomenon is most intense for colours of shorter wavelength. Consequently, for white light, the colours of the blue-violet region of the spectrum are most affected. Some of the experiments presented in this article are related to the polarization state of dispersed light through colloidal media. [ABSTRACT FROM AUTHOR]

The hourly monthly mean atmospheric pressure variation has a semidiurnal oscillation of few hectoPascals (between approximately 4 and 2 hPa), an effect known as barometric tide. The existence of this oscillation is well known but not well documented, so this work describes the monthly barometric tide for some synoptic stations from Argentina. The semidiurnal variation of pressure is more important during the warm months. The principal maximum and minimum take place between 12 and 14 UTC and 20 and 21 UTC and presents three types of behaviors. The Central and East regions, where the amplitude decreases as the latitude increase and show an important seasonal cycle. The Patagonia region, with smaller amplitude but showing a greater difference between summer and winter than the previous region. And the West region, which has the largest wave amplitude and also the largest difference between summer and winter. The wavelength is 5 hours greater in summer than in winter for the whole synoptic stations studied. The amplitude of these oscillations would modulated not only by the effect of heat from the sun but also for other local effects. Depending of the time of the day, the barometric tide affects in a different way the depth of pressure systems. So this result should be taken into account when defining and characterizing the depth of cyclones / anticyclones for the analyses and weather forecast. [ABSTRACT FROM AUTHOR]

The effect of batch thermal processing on the residual activity of pectinmethylesterase enzyme (PME) in tree tomato (Solanum betaceum) was studied. Batch processes were conducted at temperatures between 40 and 90°C and exposure times from 5 to 20s. Residual enzyme activity was spectrophotometrically measured at 620 nm wavelength. The protein content was determined according to Bradford's dye binding method. The thermal treatment applied to 60°C for 20 seconds exposure time, reduced the residual activity of PME to 10% avoiding phase separation. It is concluded that the thermal treatment applied caused a decrease on enzyme content to 28% from initial content. [ABSTRACT FROM AUTHOR]

Utilizing fluorescence, we generated excitation-emission matrices, which provided us with a map of fluorophores present in keratin tissues. Our findings suggest that all of the tested keratin substrates have features in common. We monitor the quantity of tryptophan as well as some of its metabolic and degradation products, the kynurenines. The peak due to kynurenine fluorescence is dominant and is a conglomerate of several molecular species including L-kynurenine, 3-hydroxykynurenine and N-formylkynurenine. The ratio of tryptophan to the kynurenines depends on the type of tissue and the amount of pigmentation present. The emission wavelength also greatly depends on these factors. [ABSTRACT FROM AUTHOR]

The benefit of migrating from fault-tolerant static WDM networks to survivable dynamic WDM networks is evaluated in terms of the trade-off between the additional network capacity (number of wavelengths) required to provide fault tolerance capability and the availability obtained by doing so. For the static WDM network case, wavelength requirements were obtained using a near-to-optimal dimensioning heuristic procedure, considering shared protection. For the dynamic WDM network case, wavelength requirements to guarantee a blocking probability threshold were evaluated using simulation-based techniques, for shared protection and restoration survivability mechanisms. Results show that, for every additional wavelength in the network, the availability gain of restored dynamic WDM networks is higher than that obtained using static or dynamic protected networks. We expect these results will help network operators in the decision making of migration processes. [ABSTRACT FROM AUTHOR]

Copyright of Momento: Revista de Física is the property of Universidad Nacional de Colombia, Departamento de Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, ultra short laser pulses (110 fs, 1 kHz; up to 1.1 mJ/pulse) were used for micromachining steel samples. Processing with ultra-short laser pulses allowed achieving circular micro holes, with precise measurements and no significant chemical or mechanical disruption of adjacent areas. The helical drilling optics system by TGSW-Stuttgart is used to generate the holes. This system allowed producing high aspect ratio and complex structures with variable diameter throughout the hole. To did this, up to three processing parameters may be changed at the same time (beam rotation speed, angle and of the beam) and during the processing. We study the influence of the laser wavelength on the holes geometry. Specific optics for both the fundamental (λ = 790nm) and second harmonic wavelength (λ = 395nm) were used to microstructure steel, comparing the results. From the study we can conclude that there aren't advantage when using the second harmonic. Weaknesses in the experimental device had been detected, to find the solution at this topics allow precisely evaluate the influence of wavelength. [ABSTRACT FROM AUTHOR]

Copyright of Revista ADM is the property of Asociacion Dental Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bistua: Revista de la Facultad de Ciencias Básicas is the property of Facultad de Ciencias Basicas de la Universidad de Pamplona and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Gravity waves can be classified according to the water depth over which they travel. These classifications are made according to the water depth value as related to wavelength. In the literature many criteria can be found to define this feature, depending on whether the purpose is to make more accurate computations or to make more practical and simple computations. All these criteria are analyzed in this work. Afterwards boundary depth values for deep waters and shallow waters are determined from different points of view, which are compared and the practical values of these are established. [ABSTRACT FROM AUTHOR]

In this work, we designed and built a fiber optic-network in the optical laboratory of the Instituto Tecnológico Metropolitano of Medellín City. This network was used to emulate different topologies in similar condi- tions to real environments with the possibility to make connections up to 45 km. In this network, an optical multiplexer based on fiber Bragg grating was implemented for wavelength division multiplexing in a passive optical network. By using this device, the transmission of four different wavelengths through 12 and 32 km of single-mode optical fiber is demonstrated with acceptable power levels in reception at 12 km. Numerical simulations show good performance of the system under extreme temperature conditions. This is the first experimental report in Colombia of an optical multiplexer for wavelength-division-multiplexed passive optical networks. [ABSTRACT FROM AUTHOR]

In presented article, it looks for a new form to solve to the problem of routing and allocation of wavelength in networks photons (RWA - Routing Wavelength Assignement). This problem has been solved dividing it in 2 subproblems, and applying to different algorithms optimizers, among them are the genetic algorithms, he himself who is used in this investigation, nevertheless has seted out the solution without dividing it, solving it of integral way. The investigation analyzes some parameters of the genetic algorithms, and they are optimized for the later use in the resolution of problem RWA. For it, simulations were made in scenes of dynamic traffic in network NSFNET. It was managed to determine the position of the reproduction, the size of reproduction and the loss of life, that optimizes the algorithm, in this work was not used mutation, due to its little relevance in improving the algorithm. Later simulations of the optimized algorithm were made in the same network, under dynamic traffic, these results will be shown in a next publication. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia en su PC is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Entérese Boletín Científico Universitario is the property of Universidad Manuela Beltran and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article a study of dimensional analysis is made and Pi theorem is applied to obtain an explicit expression to calculate wavelength which is compared with other analytical expressions. Also a formula is obtained to correlate errors with dx which can be used in case a graphic method is applied. Lastly, a comparative analysis between iterative methods is made. [ABSTRACT FROM AUTHOR]

The key concepts of light source, visible spectro, wavelength, absorbance, transmitance were boarded in virtual instruments for the educational support in the subjet of experimental physichemistry where the student, approaches these basic principles to include and understand phenomena of absorption of light at molecular level and the form that is applied to the quantitative analysis of substances. These virtual instruments were developed by means of the use of a computer a card of data acquisition and software of National Instruments. The instruments, interactive and simple, have been developed in the language intuitive of graphical programming LabVIEW that has applications in the industry and the academy in its 21 years of history. [ABSTRACT FROM AUTHOR]

Spin-orbit effects has been recently considered in order to study collective properties of quasi-two-dimensional electron gas (2DEG) such as plasmons, magnetoplasmons and screening effects. In this work we use the model hamiltonian proposed recently by Valín-Rodríguez and Nazmitdinov in order to consider the role of the Bychkov-Rashba and Dresselhaus spin-orbit effects for a 2DEG in the presence of an applied perpendicular magnetic field. We obtained for the zero temperature limit the magnetoplasma oscillation dispersion relation in both the long and short wavelength limits. It is shown that, for a given value of the Bychkov-Rashba spin orbit interacction, the long wavelength curve is weakly affected by the Dresselhauss term. On the other hand, in the short wavelength limit the characteristic oscillations of the dispersion curve show a strong dependence on the relation between the strengths of the Bychkov-Rashba and Dresselhauss terms. [ABSTRACT FROM AUTHOR]

In this paper we studied the main conditions for the Plasmas generation air, copper and aluminum, using a laser Nd: YAG pulsed with wavelength 1064 nm with a pulse of 500 mJ Energy and 9 ns duration at a repetition rate of 10 Hz. Through spectroscopy, we have analyzed Optical Emission lines Spectral emission, which were obtained by varying the Atmospheric pressure. Emissivity to High pressure is greater because of the confinement of the plasma and Increasing collisions between different species, in the case Plasma in the air we compared the data obtained from each Wavelength due to each transition and electronic state of Ionization with wavelengths characteristic of each Element reported by the database of the NIST (National Institute of Standards and Technology). [ABSTRACT FROM AUTHOR]

This paper presents experimental results of indoor MIMO wireless channel and channel capacity evaluation for compact PIEA (Planar Inverted "F" Antenna) antenna arrays at the 2.45 GHz frequency band. Linear and square array configurations are evaluated using PIFA antenna elements because of its advantages of low profile and flexible configuration design for compact and portable mobile terminals. Measurements are performed using a VNA with GPIB standard for automatic data acquisition. MIMO channel capacity results are calculated from a large amount of data combining uncorrelated space and frequency measurements, obtaining results that are statistically representative. Antenna array size from 0.1 to 0.8 wavelengths are tested to evaluate the effect of mutual coupling. Results show that the most efficient configurations can provide high capacity for array size as small as 0.3 to 0.4 wavelengths, which is a significant compact array size for portable wireless terminals (about 4 centimeters for the tested frequency). [ABSTRACT FROM AUTHOR]

An experimental setup for the fabrication of optical waveguides by means of ion exchange process is developed and the planar optical waveguides by the different controllable parameters in the fabrication process are obtained. Additionally, an experimental setup for the optics characterization of waveguides is developed, that allows accomplish semi-automated measurements of different angular position values of the propagation modes. An interface in Delphi 6.0 for the IWKB ( Inverse Wentzel Kramers Brillouin ) program is developed, that allows the determination of the refractive index profiles of waveguides fabricated. As result of the developed processings, the technological letters of fabrication process for the different parameters of waveguides are obtained. [ABSTRACT FROM AUTHOR]

The interference of two or more waves can be described by means of the interaction among them. In this work we present a study of this phenomenon for the case of the Young's experiment of of the double slits using the method of finite differences in the temporal domain. The simulation of the experiment is made by using the technique of Crank-Nicholson, and the spatial propagation of the light that emerges from the slits is analyzed. In the results you can appreciate the behavior that present the light varying the separation between the slits and the wavelength of the source. The exposed method is present in such a way that can be easily adjusted to other cases of interferometry. [ABSTRACT FROM AUTHOR]

The article offers information on the high resolution of precipitation with ordinary storms including interpolation of the accumulations of precipitation recorded in the rain gauges, remote sensing and electromagnetic signal into the atmosphere. Topics include different wavelengths, storm clouds and strong vertical currents.

A Zerny-Turner type monochromator has been designed, whose spectral sweep is obtained from the rotation of a diffraction grating which selects the wavelengths by reflection of the incident beam. The rotation of the grating is controlled with a step motor. The scattered radiation is focused on a photodiode type sensor with a known spectral response. The wavelengths and intensities are collected through a home made data acquisition system and virtual instruments developed with the graphic programming language LabVIEW. [ABSTRACT FROM AUTHOR]

A microwave system with wavelength of about 3 cm is used to illustrate the various electromagnetic waves phenomena. The device let to measure the relative magnitude of the received signal with an array of light emitting diodes located in front of the receiver, and provides a graph of length proportional to the intensity of the signal picked up by the receiver. [ABSTRACT FROM AUTHOR]

X Ray Spectrometry is a set of techniques that allows to detect and quantify the sample composition of unknown material by its irradiation with X Rays. This technique is characterized by the fact that the resulting radiation from the analysis is decomposed in its different wavelengths or spectra for the analysis on the elements or compounds that the sample contains. The fluorescent X Rays have a wavelengths greater than those of primary X Rays, these are characteristic of irradiated or radiator material, their emission are always accompanied by photoelectrons and the wavelengths of this rays are independent from the primary radiation wavelengths. [ABSTRACT FROM AUTHOR]

In the present paper we conducted a study about obtaining the propagation modes in an optic fibre of index step profile, in a theoretical way (where the description of the characteristic propagation, Modes, was obtained when solving the Maxwell's equations for a cylindrical waveguide with frontier conditions settled by the geometry of the fibre), digital, and with experimental implementation, where we observe the characteristic modes (EH, HE, TE and TM) and the modes lineally polarized, in which we found that a fibre of the mentioned type can be characterized by the number-V (characteristic waveguide Parameter or normalized wavenumber), as monomode, if V < 2.405, or multimode, if V > 2.405, and this parameter V is in function of the wavelength (of illumination of the fibre), core radius of the fibre and the numeric aperture (Indexes of refraction of the core, n2, and of the cladding, n2, here the indexes follow the condition: n1 - n2 <<< 1). [ABSTRACT FROM AUTHOR]

A study of Si-doped GaAs layers is presented herein. The layers were studied by micro-Raman (μR) and Cathode luminescence (CL). The μR technique allowed determining the concentration and mobility of the charge carriers. The study of doping profiles in the doped samples by CL determined the presence of emission peaks with different wavelengths that suppose the formation of several silicon complexes in the doped layers. By means of the study of the CL spectra in the n doped layers with temperature, it was possible to determine the energy of activation of two of the existing emitting centers. The behavior of the luminescence associated with the silicon complexes is analyzed using the model of configuration of coordinates. [ABSTRACT FROM AUTHOR]

The article focuses on the intensive work in the employment of wavelengths in the range from 0.780 to 0.900 μm for light sources used in automatic polarimeters. Due to the strong influence of the wavelength in the optical angular rotation, spectral bandwidth of said light sources constitutes a critical aspect for its application in automatic polarimeters. Results of the measurements with a polarimeter that employs a 0.783 μm diode laser as light source were also obtained.

Using the paraxial ray theory in the second order approximation of the traveltimes, we can estimate the traveltime function of a wavefront coming from a reflector, and in consequence calculate the diffraction traveltime function associated with a diffractor point located on the reflector. The numerical knowledge of those two functions makes possible a process to migrate stacked sections in time, process which generate images of seismic sections with true amplitudes. The restitution of the wave amplitude is made using an operator which depends of the parameters of the traveltime function. A differentiation filter is applied to the migrated sections in order to obtain the original wave phase. Layered models with smooth interfaces are used. [ABSTRACT FROM AUTHOR]

In the present work the calibration of the Red Perspex 4034AE and Clear Perspex HX (Batch No.7) dosimeters was carried out to a wave length of 615,640 nm and 305, 315 nm respectively. It was studied the influence of the time elapsed between the irradiation and the spectrofotometric readout on the value of specifical induced absorbance to different wavelength and doses. The Perspex dosimeters were used in the control of the absorbed dose by biological products with satisfactory results in the conditions of our laboratory. [ABSTRACT FROM AUTHOR]

In this work, are presented the results obtained in the production of porous silicon (SP) type p with resistivity of 0,1 Ωm, using a pulsed laser that it emits in three wavelenghts, 1064, 532 and 355 nm, with energies of 900mJ, 450mJ, and 200mJ respectively, with frequency repetition pulse of 10 Hz and with emission times of 6 ns, 5ns respectively. The pore size has been determined in function of exposure time on the silicon wafer of the radiation laser, simultaneously to the three wavelengths. The characterization of the pore size has been carried out by Scanning Electronic Microscopy (SEM), with which we determine that the SP has a spherical micro-structure with pore size in the order of micron. [ABSTRACT FROM AUTHOR]