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Independent dynamics of slow, intermediate, and fast intracranial EEG spectral activities during human memory formation
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Analysis of spectral data by complementary methods. Inspection of the molecular complex in N,N-dimethylformamide - methanol mixtures
PublicationDane widmowe FTIR mieszanin N,N-dimetyloformamidu z metanolem poddano anlizie faktorowej oraz analizie metodą ważonych widm różnicowych. Przydatność obu metod analizy w odniesieniu do układów z wiązaniem wodorowym poddano krytycznej dyskusji. Stwierdzono obecność kompleksu molekularnego typu 1:1 w całym zakresie składów mieszanin. Forma tego kompleksu zależy jednak od składu roztworu. Postulowano występowanie słabych wiązań wodorowych...
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Spatially Resolved Degradation in Heterophasic Polymers From 1D and 2D Spectral–Spatial ESR Imaging Experiments
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SPECTRAL RESPONSE OF STATIONARY JACK-UP PLATFORMS LOADED BY SEA WAVES AND WIND USING PERTURBATION METHOD
PublicationThe paper addresses non-linear vibrations of offshore jack-up drilling platforms loaded by sea waves and wind in their stationary condition using the perturbation method. Non-linearity of dynamic equations of motion for fixed offshore platforms yields from two factors. The first is load excitation generating non-linear velocity coupling in a dynamic system. This coupling is inherent in the modified Morison equation, involving the...
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Lattice filter based multivariate autoregressive spectral estimation with joint model order and estimation bandwidth adaptation
PublicationThe problem of parametric, autoregressive model based estimation of a time-varying spectral density function of a multivariate nonstationary process is considered. It is shown that estimation results can be considerably improved if identification of the autoregressive model is carried out using the two-sided doubly exponentially weighted lattice algorithm which combines results yielded by two one-sided lattice algorithms running...
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Examination of Spectral Properties of Medicinal Plant Leaves Grown in Different Lighting Conditions Based on Mint Cultivation
PublicationCultivation in controlled environmental conditions can provide good quality medicinal herbs with consistent properties. A sensing system that can determine the contents of medicinal substances in plants using spectral characteristics of leaves would be a valuable tool. Viability of such sensing approach for mint had to be confirmed experimentally, as no data correlating contents of medicinal substances with spectral characteristics...
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Measurements of Spectral Spatial Distribution of Scattering Materials for Rear Projection Screens used in Virtual Reality Systems
PublicationRapid development of computing and visualisation systems has resulted in an unprecedented capability to display, in real time, realistic computer-generated worlds. Advanced techniques, including three-dimensional (3D) projection, supplemented by multi-channel surround sound, create immersive environments whose applications range from entertainment to military to scientific. One of the most advanced virtual reality systems are CAVE-type...
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A higher order transversely deformable shell-type spectral finite element for dynamic analysis of isotropic structures
PublicationThis paper deals with certain aspects related to the dynamic behaviour of isotropic shell-like structures analysed by the use of a higher order transversely deformable shell-type spectral finite element newly formulated and the approach known as the Time-domain Spectral Finite Element Method (TD-SFEM). Although recently this spectral approach is reported in the literature as a very powerful numerical tool used to solve various...
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The power spectral density of audible noise and electric disturbances in ship’s electrical drive systems with frequency converters
Open Research DataThe presented dataset is part of research focusing on the impact of the ship's electrical drive systems with frequency converters on vibrations and the level of audible noise on ships.
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Extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in a neonatal unit: control of an outbreak using a new ADSRRS technique
PublicationSzczepy Klebsiella pneumoniae (EPKP)produkujące beta-laktamazy o rozszerzonym spektrum substratowym (ESBL)stanowią często problem zakażeń na oddziałach noworodkowych. Izolaty od 149 pacjentów poddano typowaniu nową metodą opartą na zjawisku supresji PCR, ADSRRS-fingerprinting, wykazując pochodzenie klonalne badanych szczepów. Użyteczność techniki ADSRRS-finerprinting została potwierdzona innymi metodami - RAPD i PFGE.
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Commercial microbiota test revealed differences in the composition of intestinal microorganisms between children with autism spectrum disorders and neurotypical peers
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Performance of the Direct Sequence Spread Spectrum Underwater Acoustic Communication System with Differential Detection in Strong Multipath Propagation Conditions
PublicationThe underwater acoustic communication (UAC) operating in very shallow-water should ensure reliable transmission in conditions of strong multipath propagation, significantly disturbing the received signal. One of the techniques to achieve this goal is the direct sequence spread spectrum (DSSS) technique, which consists in binary phase shift keying (BPSK) according to a pseudo-random spreading sequence. This paper describes the DSSS...
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The role of Herzberg-Teller effects on the resonance Raman spectrum of trans-porphycene investigated by time dependent density functional theory.
PublicationThe S1 excited state properties as well as the associated absorption and resonance Raman (RR) spectra of trans-porphycene are investigated by means of time dependent density functional theory calculations. The relative magnitude of the Franck-Condon (FC) contribution and of the Herzberg-Teller (HT) effects is evaluated for both the absorption and RR intensities. The accuracy of the calculated spectra is assessed by employing different...
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Dynamic analysis of the impact of the wind spectrum according to the theory of Davenport for lightweight structures of the roof in sports hall Czyzyna in Cracow.
PublicationThe main aim of this analysis is to characterize numerical simulations connected with modeling dynamic influence of wind on the lightweight structures of the roof in sports hall – “Czyżyna”. This hall is built in Cracow. The article also involves the proposals of the solutions connected with dynamic influence of the wind – Davenport’s method has been used. These proposals have not been taken into consideration at the detailed engineering...
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Small signal spectra of complex capacitance obtained on organic heterojunction formed from copper phthalocyanine and perylene dye
PublicationPraca przedstawia małosygnałowe widma zespolonej pojemności otrzymane na strukturze z heterozłączem organicznym CuPc/Py-PTC w zakresie 25Hz-1MHz.
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Chemometric determination of solute-affected solvent vibrational spectra as a superior way of information extraction on solute solvation phenomena
PublicationW pracy zaprezentowano dwie chemometryczne metody wyznaczania widm zaburzonych rozpuszczalnika oraz liczby cząsteczek zaburzonych, na podstawie zmierzonych serii wibracyjnych widm FT-IR roztworów substancji. Pierwsza z metod została stworzona na podstawie Namiarowej Analizy Faktorowej (ang. Target Factor Analysis). Druga z nich wykorzystuje algorytm izolacji widm czystych składników z serii widm mieszanin. Działanie obu metod zostało...
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Manifestation of Intermolecular Interactions in the IR Spectra of 2- and 4-Methylmethcathinones Hydrochlorides: DFT Study and Hirshfeld Surfaces Analysis
PublicationThis paper reports a Hirshfeld surfaces analysis of crystalline 2- and 4-methylmethcathinone (2-MMC and 4-MMC) hydrochlorides to analyze NH∙Cl and CH∙∙∙Cl intermolecular interactions and approve the formation of the NН2+–Cl– salt fragment in both 2-MMC∙HCl and 4-MMC∙HCl crystals. Two isomeric dimers were separated from the corresponding crystal packing to model IR spectra of the crystalline 2-MMC∙HCl...
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Measurements of high-temperature emission spectra of highly irradiated LiF:Mg,Cu,P (MCP-N) TL detectors
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Study of the Experimental and Simulated Vibrational Spectra Together with Conformational Analysis of Thioether Cyanobiphenyl-Based Liquid Crystal Dimers
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Ab initio study of phenyl benzoate: structure, conformational analysis, dipole moment, IR and Raman vibrational spectra
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Density Functional Theory Studies on Ir Spectra of the Triphenylene Derivatives. A Scaled Quantum Mechanical Force Field Approach
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Theoretical Modeling of High-Resolution X-ray Spectra Emitted by Tungsten and Molybdenum Ions from Tokamak Plasmas
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A study of the photoelectron spectra of α-tetrahydrofurfuryl alcohol over the outer valence energy region (9–25 eV)
PublicationPhotoelectron spectra of α-tetrahydrofurfuryl alcohol (THFA) molecules, the threshold spectrum and spectra for constant photoelectron energies, have been measured over the photon energy range 9–25 eV. Analysis of the photoelectron spectra has allowed overlapping photoionization bands to be separated, tentatively assigned and their vertical photoionization energies to be determined. These energies are compared with existing theoretical...
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High yield synthesis and preliminary spectroscopic study of mono-N-alkylated cyclen derivatives of salicylic acid
PublicationW artykule przedstawiono reakcję bezpośredniego alkilowania cyklenu bromopochodnymi kwasu salicylowego. Otrzymane związki wykorzystano do badań spektroskopowych. Stwierdzono, że tworzą one wybiórczo kompleksy z jonami metali grupy II. Wyznaczono stałe tworzących się kompleksów.
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On the efficiency of bile salt for stable suspension and isolation of single-walled carbon nanotubes—spectroscopic and microscopic investigations
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Microscopic and Spectroscopic Imaging and Thermal Analysis of Acrylates, Silicones and Active Pharmaceutical Ingredients in Adhesive Transdermal Patches
PublicationDermal or transdermal patches are increasingly becoming a noteworthy alternative ascarriers for active pharmaceutical ingredients (APIs), which makes their detailed physicochemical evaluation essential for pharmaceutical development. This paper demonstrates mid-infrared (FTIR) and Raman spectroscopy with complementary microscopic methods (SEM, optical and confocal Raman microscopy) and differential scanning calorimetry...
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Microscopic and Spectroscopic Imaging and Thermal Analysis of Acrylates, Silicones and Active Pharmaceutical Ingredients in Adhesive Transdermal Patches
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Homoleptic mono-, di-, and tetra-iron complexes featuring phosphido ligands: a synthetic, structural, and spectroscopic study
PublicationWe report the first series of homoleptic phosphido iron complexes synthesized by treating either the β-diketiminato complex [(Dippnacnac)FeCl2Li(dme)2] (Dippnacnac = HC[(CMe)N(C6H3-2,6-iPr2)]2) or [FeBr2(thf )2] with an excess of phosphides R2PLi (R = tBu, tBuPh, Cy, iPr). Reaction outcomes depend strongly on the bulkiness of the phosphido ligands. The use of tBu2PLi precursor led to an anionic diiron complex 1 encompassing a planar...
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Synthesis, crystal structure and spectroscopic characterization of new anionic iridium(III) complexes and their interaction with biological targets
PublicationThe synthesis and characterisation of new anionic iridium(II) complexes (NH4)2[IrCl4(κ2N,N’-H2biim)]2 · 5H2O (1) and ((CH3)2NH2)[IrCl4(κ2N,N’-PyBIm)] · H2O (2) are presented in this article. Spectroscopic methods (1H, 13C and 15N NMR, FTIR, UV-Vis) were used to characterize these new complexes. Solid-state structural analysis (SC-XRD) of complexes 1 and 2 shows a slightly distorted octahedral geometry of Ir(III) ions, which is...
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Spectroscopic studies of a ring opening process between epoxy- and aminosilanes and imine formation reactions in aqueous solutions
PublicationNMR and Raman spectroscopy studies were performed for different 3-aminopropyl(trimethoxy)- and 3-glycidoxypropyl (trimethoxy)silane based sol-gel systems containing different ketones. Exceptionally stable imine products were obtained depending on a reaction system at alkaline pH conditions and in the presence of water. These imine formation reactions were carried out without further catalyst. In addition, effect of water for the...
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Fourier transform infrared spectroscopic and theoretical study of water interactions with glycine and its N-methylated derivatives
PublicationZbadano hydratację glicyny i jej metylowych pochodnych: N-metyloglicyny (NMG), N,N-dimetyloglicyny (DMG) i N,N,N-trimetyloglicyny (TMG) przy wykorzystaniu spektroskopii FTIR, z zastosowaniem cząsteczki HDO jako sondy molekularnej. Ilościowa wersja metody widm różnicowych pozwoliła na wyizolowanie widma wody zaburzonej przez substancję rozpuszczoną. Wyniki widmowe zostały skonfrontowane z obliczeniami teoretycznymi w ramach teorii...
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Application of advanced spectroscopic methods in the assessment of the leachability degree of hazardous elements from the matrix of cellular concretea
PublicationDue to its structure, autoclaved cellular concrete exhibits good insulating properties with relatively high compressive strength values. It is increasingly used in construction because of its economic attractiveness. Autoclaved cellular concrete is mainly used in interior structure layers, and therefore its potential exposure to heavy metal leaching from the matrix may be related to the presence of a high pH medium from other materials...
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Syntheses, spectroscopic and structural properties of phenoxysilyl compounds: X-ray structures, FT-IR and DFT calculations
PublicationThe reaction of silicon disulfide with alkylphenols leads to tetraphenoxysilane, cyclodisilthiane and silanethiol. The products of the reaction of silicon disulfide with phenols are characterized by FT-IR, NMR, X-ray diffraction and DFT calculations. The intramolecular interactions in the compounds are mainly XH---π (X = C, S) whereas the intermolecular interactions are either very weak CH---π/CH---O contacts found in aryloxysilane...
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Nano-particle doped hydroxyapatite material evaluation using Spectroscopic Polarization Sensitive Optical Coherence Tomography
PublicationBio-ceramics such as hydroxyapatite (HAp) are widely used materials in medical applications, especially as an interface between implants and living tissues. There are many ways of creating structures from HAp like electrochemical assisted deposition, biomimetic, electrophoresis, pulsed laser deposition or sol-gel processing. Our research is based on analyzing the parameters of the sol-gel method for creating thin layers of HAp....
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Use of impedance spectroscopy to evaluate the durability of protective coatings after thermal shock
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Depression as is Seen by Molecular Spectroscopy. Phospholipid- Protein Balance in Affective Disorders and Dementia
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Synthesis, spectroscopy and computational studies of some biologically important hydroxyhaloquinolines and their novel derivatives
PublicationA series crystalline compounds of methyl and phosphinyl derivatives of 2-methylquinolin-8-ol (1a) and related 5,7-dichloro-2-methylquinolin-8-ol (1b) were quantitatively prepared and characterized by microanalysis, IR, UV-vis and multinuclear NMR spectroscopy. Five of them have been characterized by single crystal X-ray diffraction method. The known compounds, 8-methoxy-2-methylquinoline (2a) and 8-methoxyquinoline (2d), were synthesised...
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Method using square-pulse excitation for high-impedance spectroscopy of anticorrosion coatings
PublicationArtykuł prezentuje metodę spektroskopii impedancyjnej przeznaczonej do diagnostyki powłok antykorozyjnych na obiektach bezpośrednio w terenie. Aby skrócić czas uzyskania widma impedancji (w zakresie od 1 mHz do 1 MHz) do kilku minut, wykorzystano sygnały harmoniczne do pomiaru widma powyżej 10 Hz a impuls prostokątny w dolnym zakresie częstotliwości. Do wyznaczania widma użyto algorytmów DSP odpowiednich do sygnału pobudzenia....
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Synthesis, spectroscopy and computational studies of some novelphosphorylated derivatives of quinoline-5,8-diones
PublicationThe neutral phosphorus nucleophiles such as R2P(=Y)M allowed the radical addition to 2-methyl-5,8-dioxo-5,8-dihydroquinoline-7-amine and N-(2-methyl-5,8-dioxo-5,8-dihydroquinolin-7-yl)acetamide giving exclusively O-phosphorylated products. All products were quantitatively prepared and characterized by microanalysis, and multinuclear NMR spectroscopy. Seven of them, have been characterized by single crystal X-ray diffraction method....
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Investigation of H2:CH4 plasma composition by means of spatially resolved optical spectroscopy
PublicationThe system based on spatially resolved optical emission spectroscopy dedicated for in situ diagnostics of plasma assisted CVD processes is presented in this paper. Measurement system coupled with chemical vapour deposition chamber by dedicated fiber-optic paths enables investigation of spatial distribution of species densities (Hx, H+, CH, CH+) during chemical vapour deposition process. Experiments were performed for a various...
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Interactions of dissolved dsDNA with intercalating drug by anodic voltammetry and spectroscopy. Influence of pH
PublicationOddziaływanie związku przeciwnowotworowego C-1305 z DNA było badane przy pomocy impulsowej voltametrii różnicowej oraz spektroskopii UV/Vis. Triazoloakrydon C-1305 oddziałuje z DNA na dwóch drogach: przez interkalacje pomiedzy pary zasad oraz przez wiązanie sie w małym rowku helisy. W fizjologicznym pH (7,4) stałe wiązania wynoszą: K1=3,36E+5 i K2=0,18E+5 [1/M] a wielkość miejsca wiązania: n1=2,5 i n2=4,0, odpowiednio dla pierwszego...
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Comparison of corrosion resistance of al-alloys by means of dynamic electrochemical impedance spectroscopy
PublicationPrzeprowadzono badania metodą dynamicznej elektrochemicznej spektroskopii impedancyjne stopów 1100 i 5162. Zaproponowano zastępcze modele elektryczne opisujące zachowanie się stopów w warunkach ekspozycji w roztworach zawierających wysokie stężenie jonów chlorkowych. Wyznaczono zmiany podstawowych parametrów elektrycznych układów zastępczych od potencjału. Stwierdzono wyższą podatność na korozję stopu 5162 w porównaniu ze stopem...
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FT-Raman Spectroscopy as a Tool to Study the Secondary Structures of Wheat Gliadin Proteins
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Stereochemical Assingment of β -lactam Antibiotics and their Analogues by Electronic Circular Dichroism Spectroscopy
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Testing interaction models by using x-ray absorption spectroscopy: solid Pb
PublicationPraca prezentuje zastosowanie metody EXAFS jako narzędzia do testowania potencjałów oddziaływań międzyatomowych używanych w symulacjach dynamiczno-molekularnych na przykładzie czystego ołowiu w fazie stałej (od temperatury pokojowej do temperatury topnienia). Testowaniu poddano następujące potencjały: dwuciałowy empiryczny potencjał Dzugutova, Larssona i Ebbsjo (DLE), potencjał ciasnego wiązania (TB) i potencjał w modelu osadzonego...
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FTIR, Raman spectroscopy and HT-XRD in compatibility study between naproxen and excipients
PublicationDetection of incompatibility between an active pharmaceutical ingredient (API) and excipients, including the selection of the most biopharmaceutical advantageous excipients is extremely important in the pre-formulation process of developing a solid dosage form technology. Therefore, having fast and reliable methods for identifying incompatibility is fundamental in pharmaceutical technology. For this purpose, combined Fourier transform...
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Biosilica from sea water diatoms algae—electrochemical impedance spectroscopy study
PublicationHere, we report on an electrochemical impedance study of silica of organic origin as an active electrode material. The electrode material obtained from carbonized marine biomass containing nanoporous diatoms has been characterised by means of XRD, IR, SEM and EIS. Dif- ferent kinds of crystallographic phases of silica as a result of thermal treatment have been found. The electrode is electrochemically stable during subsequent cyclic...
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Application of Electrochemical Impedance Spectroscopy to evaluate cathodically protected coated steel in seawater
PublicationTwo types of organic coated carbon steel (S235JR2 grade) electrodes were exposed to artificial seawater environment. One prepared type was defect free while the other one had an intentionally introduced φ0,5 cm coating defect. Both kinds of samples were polarized during the exposure to four potentials corresponding to four different cathodic protection levels. Evolution of their EIS spectra is presented in this paper. Results obtained...
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Ultrastructural analysis of the submandibular sialoliths: Raman spectroscopy and electron back-scatter studies
PublicationThe aim of work was the epidemiological analysis of the occurrence of sialolithiasis of the submandibular gland in adults and the evaluation of the ultrastructure of salivary stones. The study sample consisted of 44 sialoliths. Analysis of the structure and chemical composition of sialoliths was performed using a Scanning Electron Microscope and Raman Spectroscopy. Comparing our results with the literature we can say that the epidemiology...
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Colored Tattoo Ink Screening Method with Optical Tissue Phantoms and Raman Spectroscopy
PublicationDue to the increasing popularity of tattoos among the general population, to ensure their safety and quality, there is a need to develop reliable and rapid methods for the analysis of the composition of tattoo inks, both in the ink itself and in already existing tattoos. This paper presents the possibility of using Raman spectroscopy to examine tattoo inks in biological materials. We have developed optical tissue phantoms mimicking...