- Romania
- Dr. Marian Vladescu is research scientist at Optoelectronics Research Center and Associate Professor / Reader at Univ... moreDr. Marian Vladescu is research scientist at Optoelectronics Research Center and Associate Professor / Reader at University Politehnica of Bucharest, his area of expertise being in optoelectronics. He has 28 yrs of overall experience in electronic design: R&D: 3 yrs in LASER telemetry, 6 yrs in power supplies, 6 yrs in implementing digital communication technologies (SDH, ATM, xDSL, GPON), 5 yrs in biometric systems, 5 yrs in omnidirectional vision systems, and 3 yrs in infrared omnidirectional illuminators.edit
Cobalt is a chemical element with symbol Co and atomic number 27 and atomic weight 58.93. 59 Co is the only stable cobalt isotope and the only isotope to exist naturally on Earth. Cobalt is the active center of coenzymes called cobalamin... more
Cobalt is a chemical element with symbol Co and atomic number 27 and atomic weight 58.93. 59 Co is the only stable cobalt isotope and the only isotope to exist naturally on Earth. Cobalt is the active center of coenzymes called cobalamin or cyanocobalamin the most common example of which is vitamin B12. Vitamin B12 deficiency can potentially cause severe and irreversible damage, especially to the brain and nervous system in the form of fatigue, depression and poor memory or even mania and psychosis. In order to study the degree of deficiency of the population with Co or the correctness of treatment with vitamin B12, a modern optoelectronic method for the determination of metals and metalloids from biological samples has been developed, Graphite Furnace – Atomic Absorption Spectrometer (GF– AAS) method is recommended. The technique is based on the fact that free atoms will absorb light at wavelengths characteristic of the element of interest. Free atoms of the chemical element can be produced from samples by the application of high temperatures. The system GF-AAS Varian used as biological samples, blood or urine that followed the digest of the organic matrix. For the investigations was used a high – performance GF-AAS with D2 – background correction system and a transversely heated graphite atomizer. As result of the use of the method are presented the concentration of Co in the blood or urine of a group of patient in Bucharest. The method is sensitive, reproducible relatively easy to apply, with a moderately costs.
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Amphetamines are a class of substances with a stimulating effect on the central nervous system. These were first synthesided in 1887 by Lazãr Edeleanu, a romanian chemist, in Germany, originally named phenylisopropylamine, but the... more
Amphetamines are a class of substances with a stimulating effect on the central nervous system. These were first synthesided in 1887 by Lazãr Edeleanu, a romanian chemist, in Germany, originally named phenylisopropylamine, but the stimulant effect of these was unknown until 1927, than it was resynthesized by Gordon Allens, who reported the sympathomimetic properties of amphetamines [1]. Urine amphetamine measurements were performed on the Viva-ProE analyzer (SIEMENS, Germany). The light source is a 12V-20W iodine quartz lamp. The range of scannable wavelengths with its own selection of 8 filters is as follows (340, 415, 505, 546, 570, 600, 660, 700 nm). The bandwidth is 8 - 12 nm. Photometric domain - Absorbance - 0.1 to 3.0. The authors present the results obtained by analyzing the urine samples from patients admitted in ICU II Toxicology with abuse substances overdose and working parameters of the Viva Pro-E System. Some of the results are presented. This analysis uses a threshold level of 300 ng / mL to distinguish positive and negative samples. The analysis provides only a preliminary analytical test result. A sample giving a change in the absorbance value (ΔA) equal to or even higher than the ΔA value of the Level 1 calibrator is interpreted as positive and the sample contains amphetamines or similar structural compounds or both.
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An indoor localization and monitoring system for equipment and people is an important issue in production area monitoring and offices, lab research, etc. Although several monitoring systems are currently under development by previous... more
An indoor localization and monitoring system for equipment and people is an important issue in production area monitoring and offices, lab research, etc. Although several monitoring systems are currently under development by previous investigators, these issues remain significant difficulties. For instance, the pyroelectric IR (PIR) system provides less accurate information of human location and is restricted when there are multiple targets. Also, the RFID localization system is constrained by its limited accuracy. In this study, we propose an indoor localization and monitoring system based on a network of PIR sensors and RFID sensors – a sensory fusion system. A sensor-network based localization method called the PIR-RFID inference algorithm is under development. This algorithm determines the fused position from both the PIR localization system and RFID signal localization system, which utilize the received signal strength propagation model. We have developed and experimentally demonstrated a networked sensory fusion system, which can be successfully applied in localize multiple targets - equipment and people. With an accurate localization mechanism for the indoor environment, the provision of appropriate tasks / services can be built for each modeled situation. What is new in this system, as an evolved sensory fusion system, is that the entire system has been designed and built according with specific requests of a real life situation, as standalone system, on its own, that is, regardless of the other systems a production area / shop floor / equipment a building can have. This system can interact with practically any systems at any level and can be adapted to virtually any existing building system.
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Drug abuse consists of the use by a subject without a medical recommendation, in quantities or with nonrecommended methods. Substance abuse also refers to their use in order to increase intellectual or physical performance, against the... more
Drug abuse consists of the use by a subject without a medical recommendation, in quantities or with nonrecommended methods. Substance abuse also refers to their use in order to increase intellectual or physical performance, against the rules established by society. Substance abuse involves the chronic use of non-medical chemicals for hedonistic or entheogenic purposes [1]. Drugs such as alcohol, antidepressants, amphetamine, barbiturates, benzodiazepines, cannabinoids, glue, cocaine, hallucinogens, metacular, narcotics, opiates, sedatives, stimulants and some organic solvents can be named [2]. Substance abuse can cause criminal or antisocial behavior, may generate long-term changes in personality [3]. Cocaine has major toxic effects on the body. Treatment of cocaine poisoning is complex. The main sales are those that can lead to patient death. For the proper treatment of any inoculation, it is necessary to identify the xenobiotic that generated it. The presence of metabolites, in the case of cocaine - ethylbenzoylcogene (EBE), provides information on the time of administration of the xenobiotic. Gas chromatography or liquid chromatography coupled with mass spectrometry is an optoelectronic method that can identify the presence of cocaine and / or EBE from biological samples. In order to increase the sensitivity of the method, a special mass metrology technique - MS/MS can be used [4, 5].
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This article highlights using liquid chromatography and the MRM method [1], the presence of fentanyl and norfentanyl [2] in a biological sample, in this case urine. In the method you can see the presence of each segment in the ion of the... more
This article highlights using liquid chromatography and the MRM method [1], the presence of fentanyl and norfentanyl [2] in a biological sample, in this case urine. In the method you can see the presence of each segment in the ion of the substance, obtained by ElectroSpray ionization [1], for which the confirmation is desired. The time of acquisition and the potential collision used to obtain it are specified. The MRM method is performed with a varying concentration gradient of between 10% and 65% [3] over a 9 minute acquisition time at a constant flow rate of 0.3 ml / minute. The gradient increases from 10% to 40% in the first two minutes, then increases from 40% to 65% over the next 3 minutes. The 65% concentration remains for the next 4 minutes.
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Cardiac Troponin T (cTnT) is a protein with molecular weight of 39.7 kDa that is involved in the regulation mechanism of cardiac muscle contraction and exclusive infarction originates. CTnT measurement of human serum is superior in terms... more
Cardiac Troponin T (cTnT) is a protein with molecular weight of 39.7 kDa that is involved in the regulation mechanism of cardiac muscle contraction and exclusive infarction originates. CTnT measurement of human serum is superior in terms of sensitivity and specificity of the identification of heart muscle enzymes measurements of heart muscle damage [2, 3]. Elevated cardiac troponin is now accepted as standard biochemical marker for myocardial infarction. The article shows a rapid test immunochromatographic with the help of optopelectronic module for fluorescence using quantum dots (QDs) of cadmium telluride (CdTe), that binding molecules with cardiac troponin T [1, 4]. This method it uses to detect the acute myocardial infarction (AMI-DETECT) and it provides faster biomarkers detection with higher sensitivity and specificity. For quantitative determination through fluorescent of bio-surfaces we realized both bio-surfaces and apparatus of fluorescence and the article presents some practical results obtained from effectuated experiments [4].
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Papaverine is an opiate alkaloid used in the primary treatment of visceral spasms, cardiac and cerebral vasospasms, and occasionally for the treatment of erectile dysfunction [1]. Although found in opium poppy, papaverine differs both in... more
Papaverine is an opiate alkaloid used in the primary treatment of visceral spasms, cardiac and cerebral vasospasms, and occasionally for the treatment of erectile dysfunction [1]. Although found in opium poppy, papaverine differs both in structure and pharmacological action for opioid analgesics, morphine and related substances [2]. Papaverine is used to treat gastrointestinal tract spasms, bile ducts, ureters as a cerebral and coronary vasodilator, subarachnoid hemorrhage [3] and a coronary artery bypass [4]. Papaverine is used as a smooth muscle relaxant in microsurgery if it is applied directly to blood vessels. In the treatment of erectile dysfunction, a papaverine gel has recently been used [5]. Also, in combination with other drugs, it is commonly used in cryopreservation of blood vessels [6, 7]. Papaverine is a direct relaxing smooth muscle, which is attributed to its ability to inhibit phosphodiesterase. It can be administered for peripheral cerebral and coronary circulation...
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The paper presents the experiments performed in order to determine the most suitable measuring mode which could be used to notably increase the accuracy of the photometric parameters determination for a white LED using a light meter with... more
The paper presents the experiments performed in order to determine the most suitable measuring mode which could be used to notably increase the accuracy of the photometric parameters determination for a white LED using a light meter with multiple measurement modes for various classic light sources like tungsten (incandescent), fluorescent, mercury and sodium based. Light meters are used for measuring the illuminance, which is a photometric parameter and its determination is based on the properties of human sight sense. Knowing how the sensitivity of the eye varies with the wavelength, the spectral response of the sensor and the spectral composition of the radiation emitted by a certain light source, a correction curve can be applied over the sensed values and obtain an accurate measurement. Nowadays many light meters can contain multiple calibration curves for typical light sources, but not for LEDs, especially for white ones. Since multiple measurements can be done using each correction curve, the authors conducted experiments to determine how to combine the aforementioned results to obtain a good estimate for the illuminance of white LEDs.
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At musical events, all the signals are summed using an audio mixer, then the resulting signal is delivered to the main sound system. In small or medium venues, the placement of the audio mixer is often not optimum (in front of the stage).... more
At musical events, all the signals are summed using an audio mixer, then the resulting signal is delivered to the main sound system. In small or medium venues, the placement of the audio mixer is often not optimum (in front of the stage). The sound engineer is in the situation in which he must make the required adjustments while being placed in a corner of the hall or right near the stage. The audience is usually placed directly in the front of the stage. The different placement of the sound engineer and the majority of the public leads to differences between the sound heard by the audience and the mixer operator. To fix this problem, the sound engineer must be able to walk around the venue and adjust the mixer from a distance. The digital audio mixers which already offer remote control are costly. The paper presents a system designed to allow the remote control the attenuation of the audio signals entering an analog mixer using an Android application which can run on a phone or tablet. This allows a critical upgrade to analog audio mixers with much lower costs than an upgrade to a digital mixer would involve.
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We report the full electrical characterization of a dye-sensitized solar cell (DSSC), in which the photovoltaic (PV) effect can be observed, under a radiation field closely resembling the AM 1.5 solar spectrum, together with an estimation... more
We report the full electrical characterization of a dye-sensitized solar cell (DSSC), in which the photovoltaic (PV) effect can be observed, under a radiation field closely resembling the AM 1.5 solar spectrum, together with an estimation of the variation of the determined parameters in the 300-400K temperature ranges, based on the electrical model and theoretical estimation techniques. The current-voltage characteristic serves as both a proof-of-existence for the PV effect and a source for electrical parameter extraction. The devices exhibits promising efficiency and fill factors if operated at convenient temperatures.
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With the emergence of LEDs, the conventional incandescent or fluorescent lighting solutions tends to be replaced by LED lighting systems. Historically, the lighting system was invented before radio communications, therefore its... more
With the emergence of LEDs, the conventional incandescent or fluorescent lighting solutions tends to be replaced by LED lighting systems. Historically, the lighting system was invented before radio communications, therefore its infrastructure is more widespread and simpler. One property of the conventional lighting sources is that the optical radiation emitted by them cannot be switched on and off fast. In the latest trends in high-speed communication, LED lighting solutions are used to transfer data. This field is known as Visible Light Communications (VLC). In previous work, the authors investigated the available bandwidth of four power LEDs1 that could be used for VLC systems. A typical low pass filter cutoff frequency identification procedure was used. For a complete characterization, the authors propose to determine the available bandwidth by investigating the switch-on time. The paper investigates the response time of power LEDs by studying four different LEDs: green, red, infrared and white. The LED driver circuit was especially designed for this application because it required very fast switch-on time.
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Since the ancient times apiculture relies one hundred percent on the bee-keeper's skills and experience. He constantly checks the hives to perform the required activities at the right moment. The rising demand for apiculture products... more
Since the ancient times apiculture relies one hundred percent on the bee-keeper's skills and experience. He constantly checks the hives to perform the required activities at the right moment. The rising demand for apiculture products leads to larger and larger apiaries, and checking every hive by hand becomes costly and time consuming. This project suggests a durable solution for bee hive monitoring. The prototype can be used by unqualified personnel, with minimum maintenance.
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Solderless assembly for electronics is a subject approached ever since RoHS EU Directive enforced lead-free technology especially since this one has revealed its limits. Electrically Conductive Adhesives (ECA) actually with a large... more
Solderless assembly for electronics is a subject approached ever since RoHS EU Directive enforced lead-free technology especially since this one has revealed its limits. Electrically Conductive Adhesives (ECA) actually with a large commercial offer but not very well characterized, became one of the alternatives to lead-free. The paper presents ECA qualification methods from mechanical and electrical properties point of view for usage as promising solution to build the electronic module, optimum on Surface Mount Technology processes or in the Occam concept using an additive process for interconnection structure. For a complete information about the bonds mechanical failure and their electrical resistance, shear tests, respectively four point electrical measurements were performed.
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The complete understanding of the electromagnetic field characteristics in artificially created bulk or thin media is essential to the efficient harnessing of the multitude of linear and nonlinear effects resulting from it. Due to the... more
The complete understanding of the electromagnetic field characteristics in artificially created bulk or thin media is essential to the efficient harnessing of the multitude of linear and nonlinear effects resulting from it. Due to the fact that recently developed artificial metastructures exhibit controllable electric and magnetic properties that are completely different from natural ones, the spectrum of behavior resulting from subjecting such media to electromagnetic fields has to be revisited. In this paper, we introduce a k-surface framework that offers complete information on the dispersion properties of media with designer electric and magnetic responses with positive and negative values, as well as for the coupling between the two. The extension from the classic k-surface case resides in the consideration of magnetic and bianisotropic materials with positive and negative permittivity and permeability values, as well as the introduction of the chirality coefficient.To illustra...
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The SW150 and the new types SW180 of Electrically Conductive Adhesives (ECA) dedicated to printing circuits1, meeting RoHS EU Directive2, were used, according to REACH EU Regulation3, to bond optoelectronics components, LED type, on test... more
The SW150 and the new types SW180 of Electrically Conductive Adhesives (ECA) dedicated to printing circuits1, meeting RoHS EU Directive2, were used, according to REACH EU Regulation3, to bond optoelectronics components, LED type, on test printed circuit boards (TPCBs) having daisy chain interconnection structures. Mechanical properties of LEDs bonds function of temperatures by measuring shear forces applied on each of bonded LEDs maintaining TPCBs at different temperature from ambient to 398 K (125°C), were investigated. The shear forces measured values, the LEDs bonds micro sections and the microfractography after shear testes analyses and interpretations, facilitate the construction of a database that provides support for the development of temperature-sensitive optoelectronic device assembling solutions by bonding, using ECA. These solutions ensure avoidance of their functional temperature failures during classical assembly processes, comparing ECA curing and reflow temperatures.
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Today fiber laser is widely used due to their performances and flexibility. They replace old types of lasers in the industrial machines. To develop a family of laser machines it is the need of having standard laser source that could... more
Today fiber laser is widely used due to their performances and flexibility. They replace old types of lasers in the industrial machines. To develop a family of laser machines it is the need of having standard laser source that could efficiently be used and replaced in the equipment, independently of the laser source or types of lasers. This paper presents the concept and development of a new fiber laser control unit developed to be used for CW, QCW or pulsed regime. Control unit could be used in multiple laser source and satisfy complex requirements. The control unit of the fiber laser source is able to be used in a different type of fiber laser like: Yb doped fiber, Erbium fiber, thulium fiber. Control unit is designed to be used direct or with minimum modifications in different laser processing applications like: marking, engraving, cutting, drilling, welding, etc. Main parameters of control unit are: 3 working regime, frequency - 1 KHz (QCW), frequency in pulsed regime : 15KHZ - ...
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Ultra-sensitive TFBAR (Thin Film Bulk Acoustic Wave Resonator) mass sensors can be used for the detection of dangerous substances. The chemically-sensitive part of such a sensor consists in a thin film of gold (Au) which covers the... more
Ultra-sensitive TFBAR (Thin Film Bulk Acoustic Wave Resonator) mass sensors can be used for the detection of dangerous substances. The chemically-sensitive part of such a sensor consists in a thin film of gold (Au) which covers the sensing area of the TFBAR and on top of which a layer of specific antibodies is deposited. TFBAR is a volume acoustic wave resonator that works in longitudinal vibration mode (thickness extension) and hence its resonance frequency is determined by the inverse of the piezoelectric layer thickness and directly proportional to the material dielectric constant. This paper presents the design and implementation of an electronic system based on a differential approach for measuring the chemical contamination-induced frequency deviation of a TFBAR sensor based on homodyne mixing of the output signals of two Pierce oscillators: a sensing one and a reference one.
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Tramadol is an opioid drug used to treat moderate to moderate pain, which has two different mechanism of action. The first is due to binding to the opioid receptor, and the second is due to the inhibition of serotonin and norepinephrine... more
Tramadol is an opioid drug used to treat moderate to moderate pain, which has two different mechanism of action. The first is due to binding to the opioid receptor, and the second is due to the inhibition of serotonin and norepinephrine reabsorption. Due to its hallucinogenic effects, tramadol is also used as a drug of abuse [1]. It is necessary to identify tramadol and its metabolites in urine specimens either for correct dosing of the tramadol in pain therapy, for monitoring the effectiveness of addiction treatment, or for acute poisoning with this opioid compound [2]. An optoelectronic gas chromatographic method coupled with mass spectrometry is presented to determine tramadol and its metabolites in urine samples [3].
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In this paper, we present the construction of a light-emitting diode (LED)-based solar spectrum simulator, oriented mainly for the testing of dye-sensitized solar cells based on ruthenium and ruthenium-based compounds. The simulator is... more
In this paper, we present the construction of a light-emitting diode (LED)-based solar spectrum simulator, oriented mainly for the testing of dye-sensitized solar cells based on ruthenium and ruthenium-based compounds. The simulator is built with inexpensive off-the-shelf components, and offers good integrability, scalability and the compatibility with incandescent light sources such as halogen lamps. To verify the properties of the simulator, we performed spectrum measurements of the device and cross-referenced them with the standard solar spectrum AM 1.5 for the terrestrial case, and with the known absorption spectrum of ruthenium. Also, we performed a full energy test on a silicon and a ruthenium-based solar cell, in natural solar light and under our simulator, and cross-referenced the quality of the obtained current-voltage characteristics.
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In this paper we apply digital holographic interferometry as a structural diagnosis tool to investigate some surface defects in a XIXth century wooden icon. We use a fully digital experimental set-up for real time acquisition and digital... more
In this paper we apply digital holographic interferometry as a structural diagnosis tool to investigate some surface defects in a XIXth century wooden icon. We use a fully digital experimental set-up for real time acquisition and digital optical reconstruction of holographic sequences. The light source is a He-Ne laser, the digital recording component consists of a CCD camera and a spatial light modulator (SLM) works as a digital holographic projector for the optical reconstruction of the interferograms. Both the acquisition set-up and the reconstruction one are functioning simultaneously therefore the changes in the surface structure are visualized in real-time like a digital holographic interferometry “fringe motion picture” with a 20 fps display. Detachment defects of the paint layer are identified using this non-destructive method and the real-time feature has proven to be useful because it gave a very useful dynamicity to the entire investigation process.
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In recent years, the development of new and simple methods for characterization of biosurfaces for rapid detection of acute myocardial infarction (AMI) is a constant concern in the immunochromatographic tests [3]. The method used in the... more
In recent years, the development of new and simple methods for characterization of biosurfaces for rapid detection of acute myocardial infarction (AMI) is a constant concern in the immunochromatographic tests [3]. The method used in the present assays can easily detect AMI markers within 15 minutes, with moderate sensitivity and specificity. The article shows a quick method of characterization with help of the fluorescence detection using quantum dots (QDs) of cadmium telluride (CdTe), binding molecules with biological samples [2,4]. This method provides a faster AMI biomarker detection and can have higher sensitivity and specificity. For quantitative determination through fluorescent of biosurfaces we realized both biosurfaces and apparatus of fluorescence.
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In this paper we present an experimental set-up for measuring small frequency differences between two RF oscillators [1] by using a homodyne detection scheme [2]. To emulate the oscillators, we used two RF sources whose output signals... more
In this paper we present an experimental set-up for measuring small frequency differences between two RF oscillators [1] by using a homodyne detection scheme [2]. To emulate the oscillators, we used two RF sources whose output signals were mixed and then the low frequency components at the mixer's output was measured with a network frequency analyzer. The purpose of these experiments was to evaluate a possible method to discriminate the resonance frequency change of a TF-BAR sensor as a response to its contamination with certain substances.
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Aluminum is a chemical element atomic number 13. It is white-silver, insoluble in water under normal conditions. Despite its natural abundance, aluminum has no known biology function. It is a toxic residue, aluminum sulphate having an... more
Aluminum is a chemical element atomic number 13. It is white-silver, insoluble in water under normal conditions. Despite its natural abundance, aluminum has no known biology function. It is a toxic residue, aluminum sulphate having an LD50 of 6207 mg/kg body, corresponding to 500 g per 80 kg person. Extremely acute toxicity without harm to health is of interest in view of the widespread occurrence of the element in the environment and in trade. Toxicity can be tracked after deposition into the bones and the central nervous system and is particularly high in patients with renal insufficiency. In very high doses, aluminum can cause neuro toxicity associated with altered function of the blood-brain barrier.
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Platinum is a malleable, ductile metal, silvery white, with atomic number 78 and atomic weight 195.09. We can find it in nature mainly as isotopes: Pt194 (32.9%), Pt195 (33.8%) și Pt196 (25.3%). Of all platinum metals, platinum has the... more
Platinum is a malleable, ductile metal, silvery white, with atomic number 78 and atomic weight 195.09. We can find it in nature mainly as isotopes: Pt194 (32.9%), Pt195 (33.8%) și Pt196 (25.3%). Of all platinum metals, platinum has the most uses and it’s the most abundant and most easily to be processed. Its use in auto catalysts results in environmental contamination of crowded cities and high-traffic roads. In medicine, Pt is used as a cytostatic drug. Specific platinum complexes, especially cis-diamminedichloroplatinum (II) (cisplatin), Cis-[oxalate (trans-1-1,2- diaminocyclohexane)] platinum(II) (oxaliplatin) and cis-diammine (1,1- cyclobutanedicarboxylato) platinum(II) (carboplatin), used in therapeutic practice [1,2]. Determination of the Pt concentration in biological samples provides medical personnel with useful information on the efficacy of the cytostatic treatment. An optoelectronic method for determining the concentration of Pt in urine, blood and hair samples collected from patients undergoing cytostatic treatment with platinum-based products is presented. To determine the concentration of Pt in biological products was used: Atomic Absorption Spectrometer model AAS-880, Atomization in the graphite furnace model GT 100, Programable Sample Dispenser PSD - Varian. Platinum concentrations of biological samples collected from platinum, based cytotoxic patients are presented. The presented method can be used to monitor platinumbased chemotherapy with platinum compounds. Graphite Furnace Atomic Absorption Spectroscopy (GF-AAS) method presented is sensitive, reproducible, and relatively easy to apply with an acceptable cost.
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The paper presents the investigations of bonds mechanical and electrical properties function of electrically conductive paste printed volumes. For the experiments, it was taken into consideration the SW180 electrically conductive paste... more
The paper presents the investigations of bonds mechanical and electrical properties function of electrically conductive paste printed volumes. For the experiments, it was taken into consideration the SW180 electrically conductive paste type which was used only for bonding chip resistors on the pads of interconnection structure having electroless Nickel immersion Gold (ENIG) finishing. The test vehicles contain a daisy-chain structure with ten 0 Ω resistors, 2512 case. The printed volume was controlled by the stencil thickness (100/150 μm). The mechanical tests (shear test) had been performed at five different temperatures (298/323/348/373/398 K) and they had been completed with electrical measurements and microstructural analysis.
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Methods for inspecting the integrity of audio recordings become a necessity. The evolution of technology allowed the manufacturing of small, performant, recording devices and significantly decreased the difficulty of audio editing. Any... more
Methods for inspecting the integrity of audio recordings become a necessity. The evolution of technology allowed the manufacturing of small, performant, recording devices and significantly decreased the difficulty of audio editing. Any person that participates in a conversation can secretly record it, obtaining their own version of the audio captured using their personal device. The recordings can be easily edited afterwards to change the meaning of the message. The challenge is to prove if recordings were tampered with or not. A reliable solution for this was the highly acclaimed Electrical Network Frequency (ENF) criterion. Newer recording devices are built to avoid picking up the electrical network signal because, from the audio content point of view, it represents noise. Thus, the classic ENF criterion becomes less effective for recordings made with newer devices. The paper describes a novel sonic watermarking (i.e., the watermark is acoustically summed with the dialogue) soluti...
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Of all platinum metals, platinum has the most uses and it’s the most abundant and most easily to be processed. Its use in auto catalysts results in environmental contamination of crowded cities and high-traffic roads. In medicine, Pt is... more
Of all platinum metals, platinum has the most uses and it’s the most abundant and most easily to be processed. Its use in auto catalysts results in environmental contamination of crowded cities and high-traffic roads. In medicine, Pt is used as a cytostatic drug. In order to study the degree of contamination of the population with Pt or the correctness of treatment with Pt, it has been developed a method for its determination from urine or blood samples with a system Graphite Furnance - Atomic Absorption Spectrometer, (GF-AAS) Varian. There are presented the methods of sampling processing for blood or urine that followed the digest of the organic matrix. In the determination of the operating parameters for the system GF-AAS, was aimed the reducing of the nonanatomic absorbance by optimizing the drying temperatures, the calcination and atomization temperatures and the removal of the nonanatomic absorbance with D2 lamp. As a result of the use of the method are presented the concentrations of Pt in the blood or urine of a group of patients in Bucharest, a city with heavy traffic of vehicles. GF-AAS method presented is sensitive, reproducible, and relatively easy to apply with an acceptable cost. With this method, the concentration of Pt can be determined from blood and urine, both in order to establish the degree of contamination with Pt and for monitoring cancer therapy with platinum compounds.
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The characterization of the quality of communication between an RFID reader and a transponder at all expected positions of the latter on the reader antenna is of primal importance for the evaluation of performance of an RFID system.... more
The characterization of the quality of communication between an RFID reader and a transponder at all expected positions of the latter on the reader antenna is of primal importance for the evaluation of performance of an RFID system. Continuing the line of instruments developed for this purpose by the authors, the present work proposes an enhanced version of a previously introduced automated platform for 2D evaluation. By featuring higher performance in terms of mechanical speed, the new version allows to obtain 2D maps of communication with a higher resolution that would have been prohibitive in terms of test duration with the previous version. The list of measurement procedures that can be executed with the platform is now enlarged with additional ones, such as the determination of the variation of the magnetic coupling between transponder and antenna across the antenna surface and the utilization of transponder simulators for evaluation of the quality of communication.
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ABSTRACT A new RFID reader for the 13.56 MHz carrier frequency was developed in the framework of the collaboration between Freaquent Frosch Electronics (FE) and the first author. The reader is intended to cover the standards ISO/IEC FDIS... more
ABSTRACT A new RFID reader for the 13.56 MHz carrier frequency was developed in the framework of the collaboration between Freaquent Frosch Electronics (FE) and the first author. The reader is intended to cover the standards ISO/IEC FDIS 18000 [1], ISO/IEC FCD 15693 [2] and to provide long-range reading as well as inventory of large collections of tags. The reader features a class E switching power amplifier in the transmission path and several means for achieving a high quality signal in the reception path. Our paper will be focused on the procedures we developed for processing, storing and decoding the signal received from tags.
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... In this way, the reader can be configured to generate the 125 KHz carrier either from ... SAM uC proved to be a good choice for the new Vegas reader design. References 1. Gaming Partners International Corporation, RFID Gaming Chips... more
... In this way, the reader can be configured to generate the 125 KHz carrier either from ... SAM uC proved to be a good choice for the new Vegas reader design. References 1. Gaming Partners International Corporation, RFID Gaming Chips and Readers, http://www.gpigaming.com ...
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Antidepressants were found in 1950. In the 1990s there was a new generation of antidepressants. They act on the level of certain neurotransmitters extrasinpatic by its growth. After their mode of action antidepressants may be: SSRIs... more
Antidepressants were found in 1950. In the 1990s there was a new generation of antidepressants. They act on the level of certain neurotransmitters extrasinpatic by its growth. After their mode of action antidepressants may be: SSRIs (Selective Serotonin Reuptake Inhibitors); (Serotonin-Norepinephrine Reuptake Inhibitors); SARIs (Serotonin Antagonist Reuptake Inhibitors); NRIs (Norepinephrine Reuptake Inhibitors); NDRIs (Norepinephrine-Dopamine Reuptake Inhibitors) NDRAs (Norepinephrine-Dopamine Releasing Agents); TCAs (Tricyclic Antidepressants); TeCAs (Tetracyclic Antidepressants); MAOIs (Monoamine Oxidase Inhibitors); agonist receptor 5-HT1A (5- hydroxytryptamine); antagonist receptor 5-HT2; SSREs (Selective Serotonin Reuptake Enhancers) and Sigma agonist receptor. To determine the presence of antidepressants in biological products, it has been used a system HPLC-MS (High Performance Liquid Chromatography – Mass Spectrometry) Varian 12001. The system is equipped with APCI (Atmospheric Pressure Chemical Ionization) or ESI (ElectroSpray Ionization) interface. To find antidepressants in unknown samples is necessary to recognize them after mass spectrum. Because the mass spectrum it is dependent on obtaining private parameters work of HPLC-MS system, and control interfaces, the mass spectra library was filled with the mass spectra of all approved antidepressants in Romania. The paper shows the mass spectra obtained in the HPLCMS system.
Research Interests: Engineering and Chemistry
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Throughout this research we substantiate that a film, a specially built thin one, having a certain configuration, can deal with incoming electromagnetic-EM waves that “hits” the film, in a very discerning manner, within the range of... more
Throughout this research we substantiate that a film, a specially built thin one, having a certain configuration, can deal with incoming electromagnetic-EM waves that “hits” the film, in a very discerning manner, within the range of ultraviolet- UV to far infrared. Configuration we built has on bottom a layer of a conducting material under a layer of a insulator having on top a pattern of “dots” of conducting material. Making adjustments regarding the dimensions, the materials of dots, we accomplished absorption resonances wavelength values of 0.35, 1.3, 12, 51microns. The specular spectra of the reflectivity is angle-conditioned evidenced by visible-toUV spectrometers[1]. The absorption highest values goes from 83% to98%. Applications for that kind of absorbers are represented by thermal detectors. There is a proportionality relation between surface structures linear dimension, the dielectric permittivity and the wavelength resonance. The dipolar plasma resonance image dipoles in the ground plane and the dipolar plasma resonance in the surface structures are coupled. Thus generates a circuit resonant LCR that describes the resonances of absorption[1].
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In the first part, this paper aims to analyze the optical and electronic performance of advanced drivers for LED lighting applications, taking into account the financial aspects. Consequently, for two price classes (low- and high-cost),... more
In the first part, this paper aims to analyze the optical and electronic performance of advanced drivers for LED lighting applications, taking into account the financial aspects. Consequently, for two price classes (low- and high-cost), we investigate the power conversion efficiency, their grid impact, lighting characteristics, and finally the cost-benefit ratio. Experimental measurements on physical prototypes validate the simulations performed with real supplying conditions. The final part of the paper explains some optimization steps for price-performance ratio according to a multicriteria matrix or to the main criteria established by the beneficiary. The study should be a useful decision making tool for both the scientific community and the contracting authorities.
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Among the anticipated benefits of collision warning and avoidance system is the potential reduction in traffic collisions, casualties due to traffic accidents are increasing day by day (and resulting deaths, injuries, and costs) caused by... more
Among the anticipated benefits of collision warning and avoidance system is the potential reduction in traffic collisions, casualties due to traffic accidents are increasing day by day (and resulting deaths, injuries, and costs) caused by human-driver errors, such as delayed reaction time, tailgating, rubbernecking, and other forms of distracted or aggressive driving. Automotive radar systems using integrated 10s GHz radar sensor techniques are currently under development. This paper describes a radar solution consisting of four sensors distributed behind the front bumper of an experimental car. Each single sensor measures the target range within a certain degree of accuracy. The system was tested in real situations for driving aid, autonomous emergency brake system, parking aid and stop and go applications. The novelty is that this system, as an evolved autonomous emergency brake system, parking aid and stop and go system has been designed and built as standalone system, on its own, that is, regardless of the other systems a vehicle can have. This system can interact with practically any systems at any level and can be adapted to virtually any existing brake system.
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Platinum (Pt) is a malleable, ductile, silver-white metal with atomic number 78 and an atomic weight of 195.09. Platinum is found in nature in metallic state, alloyed with small amounts of iron, copper, other platinum metals, and... more
Platinum (Pt) is a malleable, ductile, silver-white metal with atomic number 78 and an atomic weight of 195.09. Platinum is found in nature in metallic state, alloyed with small amounts of iron, copper, other platinum metals, and sometimes with little gold. This ore appears as granules or nuggets, weighing from a few milligrams to a few pounds, scattered in a silicate (olivine and piroxene). Urine samples (10 ml spot), were collected from patients admitted to the Clinical Toxicology Section. Expert literature recommends the determination of platinum in the normal population of the area as the amount of platinum present in the environment differs. For determination of platinum in biological products an installation consisting of Atomic Absorption Spectrometer Model AAS-880, Atomizing in graphite furnace model GT 100, Autosampler model PSD - Varian. Graphite Furnace Atomic Absorption Spectroscopy (GF-AAS) optoelectronic method presented is a fast, reproducible, with a very good sensit...
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Mass spectrometry is an optoelectronic method of identifying organic substances by comparing their mass spectrum of the analyte with the mass spectra deposited in the mass spectrum libraries of the system. High Pressure Liquid... more
Mass spectrometry is an optoelectronic method of identifying organic substances by comparing their mass spectrum of the analyte with the mass spectra deposited in the mass spectrum libraries of the system. High Pressure Liquid Chromatography (HPLC) coupled with Mass Spectrometry (MS) has as main objective the identification of drugs with a molecular molecule of less than 1500 amu (atomic mass units) [1]. To identify the biological products of antidepressants SSRIs have been deposited in the mass-spectra of the MI library, mass spectra obtained in a HPLC-MS interface with ElectroSpray Interface (ESI) or Atmospheric Pressure Chemical Ionization (APCI). In the paper are presented the mass spectra of selective serotonin reuptake inhibitors (SSRIs): citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine and sertraline, obtained on a HPLC system MS equipped with ESI or APCI.
Research Interests: Engineering and Medicine
This paper presents Monte Carlo simulations of the time-of-flight measurement for a unidimensional lattice of an organic semiconductor sample, under Gaussian Disorder Model assumptions, in which charge carriers follow a hopping transport... more
This paper presents Monte Carlo simulations of the time-of-flight measurement for a unidimensional lattice of an organic semiconductor sample, under Gaussian Disorder Model assumptions, in which charge carriers follow a hopping transport mechanism. Mobilities for different values of the applied electric field have been computed, and the power conversion efficiency of the sample is determined as a function of the electric field. With the extracted data, it is shown that there is an optimal field value at which high mobility and efficiency can be obtained.
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The problem of noise introduced by optocouplers has been well documented and should be a concern for electronic designers. The paper investigates the effect of phase jitter introduced by optocouplers into systems that are sensitive to... more
The problem of noise introduced by optocouplers has been well documented and should be a concern for electronic designers. The paper investigates the effect of phase jitter introduced by optocouplers into systems that are sensitive to this type of noise, mainly paying attention to RFID systems.
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Establishing an optoelectronic method for the determination of synthetic cannabinoids and their metabolites is necessary because synthetic cannabinoids are a group of psychoactive compounds designed to mimic the effects of marijuana.... more
Establishing an optoelectronic method for the determination of synthetic cannabinoids and their metabolites is necessary because synthetic cannabinoids are a group of psychoactive compounds designed to mimic the effects of marijuana. These compounds are usually sprayed on natural plants in order to be smoked. Several synthetic cannabinoids can be found on these smoked plants simultaneously. Their effective dose is lower than that of natural marijuana but with high psychoactive potency [1]. Due to their high potential for abuse and availability, these compounds are considered to be narcotic drugs. Thus, there has been an increased demand for the development of sensitive, reliable, robust and sustainable analytical methods for the identification and quantification of these compounds by clinical, forensic and toxicological laboratories [2]. The method presented in the paper will be based on liquid chromatography with a mass spectrometer detector (LCMS/ MS). The paper aims to obtain, us...
Research Interests: Engineering and Chemistry
In this paper is described 3D simulation for solitions used in optical fibers. In the scientific works is started from nonlinear propagation equation and the solitons represents its solutions. This paper presents the simulation of the... more
In this paper is described 3D simulation for solitions used in optical fibers. In the scientific works is started from nonlinear propagation equation and the solitons represents its solutions. This paper presents the simulation of the fundamental soliton in 3D together with simulation of the second order soliton in 3D. These simulations help in the study of the optical fibers for long distances and in the interactions between the solitons. This study helps the understanding of the nonlinear propagation equation and for nonlinear waves. These 3D simulations are obtained using MATLAB programming language, and we can observe fundamental difference between the soliton and the second order/higher order soliton and in their evolution.
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Super-capacitors are highly reliable devices, outlasting any existing battery in operating conditions, cycle number and ruggedness. They are perfect candidates for energy storage in remote wireless sensor network nodes. Other applications... more
Super-capacitors are highly reliable devices, outlasting any existing battery in operating conditions, cycle number and ruggedness. They are perfect candidates for energy storage in remote wireless sensor network nodes. Other applications [1] use a combination of rechargeable battery as the main storage device and a low capacity EDLC as energy buffer. This paper describes the design and the results from a module consisting of a single large capacitor, a MPPC charger and a boost converter. Unlike other devices, this prototype uses one storage device (a single EDLC), it does not involve software components [2] and it can operate from a single solar cell.
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A theoretical characterization of an organic solar cell has been realized based on its equivalent model and an I-V curve corresponding to ITO/PEDOT/MEH-PPV:PCBM(1:4)/LiF/Al cell, taken from the literature. The parameters of the equivalent... more
A theoretical characterization of an organic solar cell has been realized based on its equivalent model and an I-V curve corresponding to ITO/PEDOT/MEH-PPV:PCBM(1:4)/LiF/Al cell, taken from the literature. The parameters of the equivalent model have been determined using two methods: the approximation method and the Lambert W function. For the considered curve, the parameter values that have been obtained are similar to the results presented in literature. It has also been shown that the Lambert W function presents a considerably smaller error compared to the approximation method.