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Search results for: visible light photoactivity
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Effects of artificial lighting on bioactivity of sweet red pepper (Capsicum annuum L.)
PublicationRecent studies have shown that artificial light effectively promotes the growth and development of red peppers when light spectra, intensities and duration are controlled. Cited reports deal mostly with studies involving with the growth stages of pepper. Changes in the biochemical status of plants were not studied. Therefore, this study focuses on the changes in the content of some bioactive compounds (polyphenols, flavonoids,...
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Problematyka dotycząca zapewnienia fotostabilności substancji leczniczych w postaciach leku
PublicationUV and visible radiation may influence on the stability of some active pharmaceutical ingredients and in a consequence destabilizes such medicinal products, causes changesin its physicochemical properties also with negative pharmacological and sometimes even toxic effects. For this reason it is important to conduct the routine testing photostability. The knowledge of chemistry and technology as well as some methods of...
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Nitrate and nitrite silver complexes with weakly coordinating nitriles
PublicationSimple system of weak nitrile ligands and silver nitrite/nitrate allowed the formation and isolation of coordination compounds of diverse nuclearity and dimensionality. The extension of the network does not enhance the luminescent properties of the ligands however it gives rise to the new MLCT bands in the visible region.
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Hydrothermal modification of TiO2 nanotubes in water and alkali metal electrolytes (LiNO3, NaNO3, KNO3) – Direct evidence for photocatalytic activity enhancement
PublicationThe influence of hydrothermal annealing (HA) of TiO2 nanotubes (TiO2-NTs) in various baths (H2O, LiNO3, NaNO3, KNO3 performed for 4 h, 24 h, 64 h), on their photocatalytic and photoelectrocatalytic properties, was studied. The use of electrolytes was to enable the monitoring of photoactivity changes as a result of the expected impact on the population of hydroxyl groups on the surface. The assumption turned out to be correct and...
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Home Sweet Home. Connecting the dots for healthy evening residential illumination
PublicationDuring the twentieth century, lighting designers would commonly use incandescent light sources for residential homes as they provided a visual comfort, with high quality colour rendering properties, along with relaxing ambient atmosphere. Unfortunately, it’s now difficult to buy incandescent light sources because they have been banned in many countries (https://bit.ly/2GwN2Wv). This article addresses some of the challenges in regards...
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Noise in biological Raman spectroscopy
PublicationRaman spectroscopy is a widely used method to investigate chemical molecules by analyzing their vibrational transitions. It utilizes inelastic scattering of the laser light irradiating the investigated object. The scattered light requires appropriate filtering to reduce dominant laser light and expose much weaker components having shifted wavelengths of a characteristic spectral pattern. These components are measured by dispersing...
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Intense and stable room-temperature photoluminescence from nanoporous vanadium oxide formed by in-ambient degradation of VI3 crystals
PublicationVanadium oxides have attracted research interest because their optoelectronic properties make them optically active with room-temperature photoluminescence (PL) emission, which, however, is not sufficiently intense for real applications. For this reason, many nanostructured vanadium oxides are currently fabricated through several precursors and different treatments to improve the PL efficiency and enhance the PL intensity. Herein,...
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Spectral measurement of birefringence using particle swarm optimization analysis
PublicationThe measurement of birefringence is useful for the examination of both technical and biological objects. One of the main problems is that the polarization state of light in birefringent media changes periodically. Without the knowledge of the period number, the birefringence of a given medium cannot be determined reliably. We propose to analyse the spectrum of light in order to determine the birefringence. We use a Particle Swarm...
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ADT in mammography
PublicationWe discuss limitations of the known methods of IR imaging in diagnostics of breast cancer. In conclusion we show that for practical reasons one requires new approaches because the known methods based on simple observation of external temperature distribution are not fully effective. Even advanced pattern recognition could not help too much for static images. We ask the question: may active dynamic thermography, known in nondestructive...
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Hyperbaric Storage at Subzero Temperature – the Effect on the Shelf-Life and Selected Quality Characteristics of Raw Pork Sausages
PublicationThe aim of this study was to determine the microbiological stability and changes occurring in selected physicochemical properties of raw pork sausages during hyperbaric storage at subzero temperature (HS-ST). It was shown that storage at moderate pressures (up to 111 MPa) led to a reduction in microbial populations. After 21 days of storage under these conditions, no microorganisms were detected in the samples. Additionally, the...
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Advanced Monte Carlo simulator of the polarization-sensitive optical coherence tomography systems
PublicationSimulations of the optical coherence tomography (OCT) systems using the Monte Carlo method is a widely explored research area. However, there are several difficulties that need to be overcome in order to properly model the OCT imaging with the Monte Carlo algorithm. First of all, the temporal and the spatial coherence of the scattered light need to be considered, since OCT is based on the interference phenomenon. For the same reason,...
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Literature review of user needs, toward user requirements
PublicationThis report has been developed in the frame of the IEA SHC Task 61 Subtask A “User requirements”. The main objective was to rethink and reformulate user requirements to lighting (daylighting and electric lighting) in public buildings on the basis of a thorough literature study. The work is a joint effort of a number of scientists and represents collective knowledge in this topic. The concept of Lighting quality is the one, among...
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Urchin-like TiO2 structures decorated with lanthanide-doped Bi2S3 quantum dots to boost hydrogen photogeneration performance
PublicationThe formation of heterojunctions between wide- and narrow-bandgap photocatalysts is commonly employed to boost the efficiency of photocatalytic hydrogen generation. Herein, the photoactivity of urchin-like rutile particles is increased by decorating with pristine as well as Er- or Yb-doped Bi2S3 quantum dots (QDs) at varied QD loadings (1–20 wt%) and doping degrees (1–15 mol%), and the best hydrogen evolution performance is achieved at...
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Photocatalytic Decomposition of Air Pollutants using Electrodeposited Photocatalysts on Stainless Steel
PublicationThe aim of research was to develop an immobilization method for photocatalysts, which is an alternative to the sol-gel or dip coating methods and can be simply scaled up for technical applications. The investigated photocatalyst was TiO2, which was electrochemically deposited onto a cathode made of stainless steel. This deposited film was photocatalytically active. In order to enhance the photoactivity of the TiO2 film, commercially...
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Design and implementation of an illumination system to mimic skyglow at ecosystem level in a large‐scale lake enclosure facility
PublicationLight pollution is an environmental stressor of global extent that is growing exponentially in area and intensity. Artificial skyglow, a form of light pollution with large range, is hypothesized to have environmental impact at ecosystem level. However, testing the impact of skyglow at large scales and in a controlled fashion under in situ conditions has remained elusive so far. Here we present the first experimental setup to mimic...
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Efficiency limit of excitonic photovoltaic cells under phosphor-based white LED illumination
PublicationThe limit of energy conversion of excitonic photovoltaic cells working under white light illumination generated by phosphor-based LED is analysed using the modified Giebink approach. Particularly, the impact of the optical energy gap and energy loss associated with the excitons dissociation at the heterojunction interface on power conversion efficiency of the device are discussed. From the results of our study it follows that the...
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HISTORIA ROZWOJU LAMP I OPRAW OŚWIETLENIOWYCH SŁUŻĄCYCH DO OŚWIETLANIA WNĘTRZ MIESZKALNYCH. CZĘŚĆ PIERWSZA
PublicationThis paper reflects on the history of decorative luminaire design. The development of the new sources of light within residential environment has been changing the luminaire design. Residential dwellings have been lit by a lot of light sources through the centuries form a point lamps like candle or incandescent lamps to linear florescent lamps and LED strips. A development of SSL technology introduced an idea of lit surfaces. Energy...
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Do We Need a Lighting Detox for Sustainable Cities in the 21st Century?
PublicationThis article looks at relearning our connection to light and dark in context of sustainability, climate change and urban lighting.
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Comparison of modelling and measurement results of spectra emitted by a programmable lamp
PublicationNowadays artificial light with an optimized spectrum is used in many different applications. For instance, it is widely used in museums and exhibitions to illuminate the art. Moreover, such light stimulates the growth of plants, or can be applied in industry and healthcare. To achieve the best results for each application, the adjusting of a dedicated spectrum is required, which is a complicated task. The ongoing research is focused...
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Establishing Relationships between Parameters of the controlled Compaction Soil by Using Various In-Situ Tests
PublicationThe aim of research was evaluating reliable correlations between chosen soil parameters describing state of surface layers of soil. The paper presents site comparative tests based on the light falling weight deflectometer (LFWD), the static plate load tester (VSS), the dynamic probing light tester (DPL) and the bearing ratio tester (CBR in-situ) with relationships between soil state parameters. All featured in-situ...
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Fluorescence Imaging Using Methylene Blue Sentinel Lymph Node Biopsy in Melanoma
PublicationIntroduction: Fluorescence imaging of sentinel node biopsy in melanoma is a novel method. Both indocyanine green (ICG) and methylene blue (MB) have fl uorescent properties. The aim of this study was to present, for the fi rst time in a clinical series of patients, the possible usage of MB as a fl uorescent dye for sentinel node biopsy during surgery for melanoma. Material and methods: Twenty patients with...
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On the mechanism of photocatalytic reactions on CuxO@TiO2 core–shell photocatalysts
PublicationTitania (titanium(IV) oxide) is a highly active, stable, cheap and abundant photocatalyst, and is thus commonly applied in various environmental applications. However, two main shortcomings of titania, i.e., charge carrier recombination and inactivity under visible-light (vis) irradiation, should be overcome for widespread commercialization. Accordingly, titania has been doped, surface modified and coupled with various ions/compounds,...
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In situ spectroelectrochemical and theoretical study on the oxidation of a 4H-imidazole-ruthenium dye adsorbed on nanocrystalline TiO2thin film electrodes
PublicationTerpyridine 4H-imidazole-ruthenium(ii) complexes are considered promising candidates for use as sensitizers in dye sensitized solar cells (DSSCs) by displaying broad absorption in the visible range, where the dominant absorption features are due to metal-to-ligand charge transfer (MLCT) transitions. The ruthenium(iii) intermediates resulting from photoinduced MLCT transitions are essential intermediates in the photoredox-cycle...
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Anatomy of noise in quantitative biological Raman spectroscopy
PublicationRaman spectroscopy is a fundamental form of molecular spectroscopy that is widely used to investigate structures and properties of molecules using their vibrational transitions. It relies on inelastic scattering of monochromatic laser light irradiating the specimen. After appropriate filtering the scattered light is dispersed onto a detector to determine the shift from the excitation wavelength, which appears in the form of...
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Degradation of modified TPS in natural and industrial compost
PublicationThe aim of the study was to determine in the pilot studies the degree of decomposition of modified by us thermoplasic starch (potato starch).Commercial and new obtained by us foils were tested in an open roofing at normal weather conditions. The most visible changes were observed in TPS modified by epoxidized soybean oil and arabic gum contrary to commercial foils where there was no mass change observed.
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Layered Morphology of Gdansk: Past, Present and Future.
PublicationThis study aims to analyze the urban fabric and form of the city of Gdańsk based on the Muratorian and Italian school of urban morphology, to deepen the understanding of the morphological process of the urban fabric. It can be seen that the urban fabric of the city is a juxtaposition of all these layers, and based on Muratori’s approach these are indicative of not just the past, present but also the future. The study sample is...
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Effect of multi-walled carbon nanotubes properties on the photocatalytic activity of bismuth-based composites synthesised via an imidazolium ionic liquid
PublicationThe use of various types of multi-walled carbon nanotubes in the synthesis of bismuth oxybromide semiconductors via imidazolium ionic liquid was studied in detail. The effect of the MWCNT shape, specific surface area, and various diameters on the morphology, surface properties and photoactivity of the Bi-based composites has been investigated for the first time. So far, the literature has only shown the enhancement of photocatalytic...
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The effect of morphology and crystalline structure of Mo/MoO3 layers on photocatalytic degradation of water organic pollutants
PublicationMolybdenum oxide layers were formed by anodization of the Mo metallic foil in a water/ethylene glycol-based electrolyte containing fluoride ions. The as-prepared, amorphous samples were annealed in air at different temperatures in a range from 100 �C to 700 �C. The crystal phase and morphology of anodized and annealed MoO3 layers were investigated using X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. The...
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Fluctuation enhanced gas sensing using UV irradiated Au-nanoparticle-decorated WO3-nanowire films
PublicationWO3 nanowires (WO3-NWs) decorated with gold nanoparticles (AuNPs) were utilized in resistive gas sensor devices to detect ethanol by use of fluctuation enhanced sensing (FES). The experimental system records both DC resistance and fluctuations of the sensing film. Our data verify that the sensitivity and selectivity of the gas sensor are improved by applying FES when the sensor is stimulated with a combination of UV light and heating....
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Towards spectral sensitivity curve for two-photon vision mechanism
PublicationAbstract Purpose: The perceived brightness of different visible light sources can be compared with photometric units based on the standardized luminosity curves (300-780nm range). As reported previously (PNAS 111(50), pp. E5445-E5454 (2014)), near-infrared (NIR) radiation can cause isomerization of visual pigments by one- or two-photon absorption. The perceived color of the stimulus is red in the case of one-photon vision (1PV)...
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Use laser to measure girder deflection
PublicationThe paper presents a new, simple way to measure deflection of selected intens using the device dkkz-2010, which user a laser light source.
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Significance of Dermoscopy in Association with Clinical Features in Differentiation of Basal Cell Carcinoma and Benign Trichoblastic Tumours
PublicationBackground: Although basal cell carcinoma (BCC) can, in the majority of cases, be diagnosed based on clinical and dermoscopic assessment, a potential overlap with benign adnexal skin tumours seems to exist, including trichoblastic tumours (TT). Methods: Retrospective analysis of clinical and dermoscopic features of benign TT and BCC cases was performed to develop a diagnostic algorithm with a potential utility in clinical practice....
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Gaseous products from scrap tires pyrolisis
PublicationIn European Union 75% of used tires should be recycled. The most common method of used tires disposal, is burning in cement kilns, which does not solve the problem. Pyrolysis process can be an alternative way of utilization of tires. The aim of the researches was to check the influence of pyrolysis products (gas and oil fractions) on environment. Samples from pyrolysis process, like light oil fractions or pyrolysis gases were analyzed...
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The influence of the development of private air communication on the architecture and urban planning of the 21st century
PublicationIn the first part, the article describes the stages of the development of gyroplanes and the influence of wartime policy on the interest in light aircraft. Also presented are links and the possibilities of using gyroplanes in various sectors of the economy. The authors, based on source texts, present the current position of the aviation industry in the Polish economy and attempt to diagnose its development capabilities. As a result,...
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Nonadditivity of quantum and classical capacities for entanglement breaking multiple-access channels and the butterfly network
PublicationWe analyze quantum network primitives which are entanglement breaking. We show superadditivity of quantum and classical capacity regions for quantum multiple-access channels and the quantum butterfly network. Since the effects are especially visible at high noise they suggest that quantum information effects may be particularly helpful in the case of the networks with occasional high noise rates. The present effects provide a qualitative...
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Production of self-compacting concrete using limestone powder
PublicationAlthough there are visible signs of its gradual acceptance in North Africa through its limited use in construction, Libya has yet to explore the feasibility and applicability of self-compacting concrete (SCC) in new construction. The current study revolves around SCC made of locally available materials and the harsh environmental conditions. This paper deals with the investigation into the effect of the water to powder ratio and...
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3D Vision System for a Robotic Arm Based on Equal Baseline Camera Array
PublicationThis paper presents a lightweight 3D vision system called Equal Baseline Camera Array (EBCA). EBCA can work in different light conditions and it can be applied for measuring large range of distances. The system is a useful alternative to other known distance measuring devices such as structured-light 3D scanners, time-of-flight cameras, Light Detection and Ranging (LIDAR) devices and structure from motion techniques. EBCA can be...
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WSN for intelligent street lighting system
PublicationIn this article authors propose to apply WSN to intelligent street lighting system. As a result of such a combination one obtains a system designed to increase functionality of light installations for a wide range of applications and introduce a platform for new additional services, which meets current and future user needs. The system is composed of WSN nodes integrated with light sources based on high power LED diodes, which...
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Probability distribution of flicker noise in AuNPdecorated graphene–Si Schottky barrier diode
PublicationWe present results of the probability distribution analysis of flicker noise generated in Au nanoparticle (AuNP) decorated graphene–Si Schottky barrier diodes with and without yellow light illumination (592 nm), close to the localized surface plasmon resonance in the AuNPs (586 nm). The AuNPs occupy imperfections in the single-layer graphene and reduce the flicker noise intensity generated in the graphene layer. The estimated probability...
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On Guard for Lighting Quality. The establishment of the first association of professional lighting designers
PublicationNot many people in the lighting community are aware of the fact, that after electricity was invented and in general use in the United States from the late nineteenth century, only electrical engineers were responsible for the illumination of architecture. After 1906, when the Illuminating Engineering Society of North America (IESNA) was established in the USA, companies and individuals professionally involved in the field of gas...
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Treated wasetewater as a source of humic substances in surface waters
PublicationHumic substances impose substantial effect on the aquatic environment as well as the water organisms and human health. Among other features, the humic acids determine organoleptic properties of surface waters. Therefore explanation of the origin and properties of humic acids in surface waters is one of the priorities of water technology.Recently it was pointed out that in the wastewater treatment process organic compounds characterized...
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Enhancement of photocatalytic-based processes by mono- and bimetallic (CuPd) rutile loaded nanoparticles for antibiotic resistance genes and facultative pathogenic bacteria removal
PublicationThe aim of the study was the strong reduction of facultative pathogenic bacteria (FPB), and clinically relevant antibiotic resistance genes (ARGs) from secondary effluent. To evaluate the ARGs removal efficiency comparative study of individual unit processes and combined AOPs has been performed. The present work investigated: i) removal of selected ARGs, namely blaTEM, ermB, qnrS, tetM, five FPB as well as 16S rDNA and the integrase...
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Valorization of waste cabbage leaves by postharvest photochemical treatments monitored with a non-destructive fluorescence-based sensor
PublicationThe biosynthesis of polyphenolic compounds in cabbage waste, outer green leaves of white head cabbage (Brassica oleracea L. var. capitata subvar. alba), was stimulated by postharvest irradiation with UVB lamps or sunlight. Both treatments boosted the content of kaempferol and quercetin glycosides, especially in the basal leaf zone, as determined by the HPLC analysis of leaf extracts and by a non-destructive optical sensor. The...
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The influence of photointercalaction and photochromism effects on the photocatalytic properties of electrochemically obtained maze-like MoO3 microstructures
PublicationMolybdenum oxide (α-MoO3) thin films with oriented crystalline facets were synthesised by anodization of Mo foils. The obtained samples were exposed to UV–Vis illumination in aqueous electrolytes providing different cations. The morphology and structure of modified samples were investigated. The effect of photointercalated alkali metal cations (Li+, Na+, K+) on optical and structural properties was studied using UV–vis and Raman...
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Impact response of two-layered grouted aggregate fibrous concretecomposite under falling mass impact
PublicationTwo-layered Grouted Aggregates Fibrous Concrete Composite (TGAFCC) is a new category concrete which became popular recently and attracted the attention of researchers globally. Recent studies indicated that TGAFCC has notable improvement in mechanical properties, which has been sufficiently documented. However, the impact behaviour of TGAFCC when combined with Glass Fibre Mesh (GFM) and Textile Fibre Mesh (TFM) is still unexplored....
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A Novel Ru(II) Polypyridine Black Dye Investigated by Resonance Raman Spectroscopy and TDDFT Calculations
PublicationThe optical properties of a new(bipyridine)2Ru(4H-imidazole) complex presenting a remarkablebroad absorption in the visible range are investigated. Thestrong overlap of the absorption with the solar radiationspectrum renders the studied complex promising as a blackabsorber and hence as a starting structure for applications inthe field of dye-sensitized solar cells. The correlations betweenstructural and electronic features for...
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A Systematic Review for Establishing Relevant Environmental Parameters for Urban Lighting: Translating Research into Practice
PublicationThe application of lighting technologies developed in the 20th century has increased the brightness and changed the spectral composition of nocturnal night-time habitats and night skies across urban, peri-urban, rural, and pristine landscapes, and subsequently, researchers have observed the disturbance of biological rhythms of flora and fauna. To reduce these impacts, it is essential to translate relevant knowledge about the potential...
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Nongeminate recombination in organic bulk heterojunction solar cells: Contribution of exciton–polaron interaction
PublicationA new model to explain nongeminate recombination in organic bulk heterojunction solar cells is presented. We suggest that the annihilation of excitons on charge carriers at the interface between donor and acceptor phases competes with the bimolecular recombination of Coulombically bound electron–hole pairs. The exciton–polaron interaction gives visible contribution to the reduction of Langevin recombination. An analytical formula,...
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Influence of sensor design and optical properties of tissue on the photoplethysmographic signal
PublicationPhotopletysmography and an associated technique called pulse oximetry are still explored due to the expectations that they give a lot of information about the state of the patient and, also, due to the fact that they are non invasive. Knowledge about the impact of various parameters on the measured signal leads to a faster and a more reliable way of analyzing measurement results and finding the dependencies between the involved...
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The Emission and Combustion Characteristics of Marine Diesel Engine with Extreme Throttled of Air or Exhaust Ducts
PublicationPresented paper shows the results of the laboratory tests on the relationship between the extreme throttling of both air intake duct and exhaust gas duct and gaseous emission from the marine engine. The object of research is a laboratory, 4-stroke, DI diesel engine, operated at loads from 50 kW to 250 kW at a constant speed equal to 750 rpm. During the laboratory tests the thermodynamic and exhaust gas emission characteristics...