Differential Optical Spectrometer based on Critical Angle Dispersion

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Simulation model of a new solar laser system of Fresnel lens according to real observed solar radiation data in

A new simulation model of a new solar pumped laser system was tested to be run in Helwan in Egypt (latitude φ = 29°52′N, longitude λ = 31°21′E and elevation = 141 m) as an example of an industrial polluted area. The system is based on concentrating the solar radiation using a Fresnel lens on a laser head fixed on a mount tracking the sun during the day and powered by a DC battery. Two cases of this model are tested; the first one is the model consisting of a Fresnel lens and a two-dimensional Compound Parabolic Concentrator (CPC), while the other is the model consisting of a Fresnel lens and a three-dimensional Compound Parabolic Concentrator (CPC). The model is fed by real actual solar radiation data taken in Helwan Solar Radiation Station at NRIAG in the various seasons in order to know the laser power got from such a system in those conditions. For the system of Fresnel lens and 2D-CPC, an average laser output power of 1.27 W in Winter, 2 W in Spring, 5 W in Summer and 4.68 W in Autumn respectively can be obtained. Accordingly, the annual average output power for this system is 3.24 W. For the system of Fresnel lens and 3D-CPC, an average laser output power of 3.28 W in Winter, 3.55 W in Spring, 7.56 W in Summer and 7.13 W in Autumn respectively can be obtained. Accordingly, the annual average output power for this system is 5.38 W

Maternal and neonatal effects of nalbuphine given immediately before induction of general anesthesia for elective cesarean section

Background: Although nalbuphine was studied extensively in labour analgesia and was proved to be acceptable analgesics during delivery, its use as premedication before induction of general anesthesia for cesarean section is not studied. The aim of this study was to evaluate the effect of nalbuphine given before induction of general anesthesia for cesarean section on quality of general anesthesia, maternal stress response, and neonatal outcome. Methods: Sixty full term pregnant women scheduled for elective cesarean section, randomly classified into two equal groups, group N received nalbuphine 0.2 mg/kg diluted in 10 ml of normal saline (n=30), and group C placebo (n=30) received 10 ml of normal saline 1 min before the induction of general anesthesia. Maternal heart rate and blood pressure were measured before, after induction, during surgery, and after recovery. Neonates were assisted by using APGAR0 scores, time to sustained respiration, and umbilical cord blood gas analysis. Result: Maternal heart rate showed significant increase in control group than nalbuphine group after intubation (88.2±4.47 versus 80.1±4.23, P<0.0001) and during surgery till delivery of baby (90.8±2.39 versus 82.6±2.60, P<0.0001) and no significant changes between both groups after delivery. MABP increased in control group than nalbuphine group after intubation (100.55±6.29 versus 88.75±6.09, P<0.0001) and during surgery till delivery of baby (98.50±2.01 versus 90.50±2.01, P<0.0001) and no significant changes between both groups after delivery. APGAR score was significantly low at one minute in nalbuphine group than control group (6.75±2.3, 8.5±0.74, respectively, P=0.0002) (27% of nalbuphine group APGAR score ranged between 4-6, while 7% in control group APGAR score ranged between 4-6 at one minute). All neonates at five minutes showed APGAR score ranged between 9-10. Time to sustained respiration was significantly longer in nalbuphine group than control group (81.8±51.4 versus 34.9±26.2 seconds, P<0.0001). The umbilical cord blood gas was comparable in both groups. None of the neonates need opioid antagonist (naloxone) or endotracheal intubation. Conclusion: Administration of nalbuphine before cesarean section under general anesthesia reduces maternal stress response related to intubation and surgery, but decreases the APGAR score at one minute after delivery. So, when nalbuphine was used, all measures for neonatal monitoring and resuscitation must be available including attendance of a pediatrician

Electrostatic Comb-Drive Actuator with High In-Plane Translational Velocity

This work reports the design and opto-mechanical characterization of high velocity comb-drive actuators producing in-plane motion and fabricated using the technology of deep reactive ion etching (DRIE) of silicon-on-insulator (SOI) substrate. The actuators drive vertical mirrors acting on optical beams propagating in-plane with respect to the substrate. The actuator-mirror device is a fabrication on an SOI wafer with 80 μm etching depth, surface roughness of about 15 nm peak to valley and etching verticality that is better than 0.1 degree. The travel range of the actuators is extracted using an optical method based on optical cavity response and accounting for the diffraction effect. One design achieves a travel range of approximately 9.1 µm at a resonance frequency of approximately 26.1 kHz, while the second design achieves about 2 µm at 93.5 kHz. The two specific designs reported achieve peak velocities of about 1.48 and 1.18 m/s, respectively, which is the highest product of the travel range and frequency for an in-plane microelectromechanical system (MEMS) motion under atmospheric pressure, to the best of the authors’ knowledge. The first design possesses high spring linearity over its travel range with about 350 ppm change in the resonance frequency, while the second design achieves higher resonance frequency on the expense of linearity. The theoretical predications and the experimental results show good agreement

Substrate signal inhibition in Raman analysis of microplastic particles

In Raman analysis, the substrate material serves very often for signal enhancement, especially when metallic surfaces are involved; however, in other cases, the substrate has an opposite effect as it is the source of a parasitic signal preventing the observation of the sample material of interest. This is particularly true with the advent of microfluidic devices involving either silicon or polymer surfaces. On the other hand, in a vast majority of Raman experiments, the analysis is made on a horizontal support holding the sample of interest. In our paper, we report that a simple tilting of the supporting substrate, in this case, silicon, can drastically decrease and eventually inhibit the Raman signal of the substrate material, leading to an easier observation of the target analyte of the sample, in this case, microplastic particles. This effect is very pronounced especially when looking for tiny particles. Explanation of this trend is provided thanks to a supporting experiment and further numerical simulations that suggest that the lensing effect of the particles plays an important role. These findings may be useful for Raman analysis of other microscale particles having curved shapes, including biological cells.Published versionThis project received support from the I-SITEFUTURE Initiative (Reference ANR-16-IDEX-0003) in the frame of the project NANO-4-WATER as well as the METAWATER Project (ANR-20-CE08-0023 META-WATER)