E. Borisova, A. Gisbrecht, Tsanislava Genova-Hristova, P. Troyanova, E. Pavlova, N. Penkov, I. Bratchenko, V. Zakharov, Ilze Lihachova, I. Kuzmina, J. Spigulis
In the current study were used excitation-emission matrices (EEMs) and synchronous fluorescence spectroscopy (SFS) steady-state techniques in a broad spectral regions (excitation at 220-500 nm and emission at 280-850 nm) to achieve the whole set of endogenous fluorophores, existed in normal and neoplastic cutaneous tissues. Several types of benign, dysplastic and malignant types of skin lesions were investigated ex vivo using both EEM and SFS modalities, namely the basal cell papilloma and carcinoma, pigmented nevi, dysplastic nevi, squamous cell carcinoma and malignant melanoma. Histological analysis was used as a “gold standard” for evaluation of clinical diagnosis of the lesions investigated. Comparison with the normal skin tissue spectral data was made, based on the signals detected from the safety margins areas of the surgically excised tumours. EEM and SFS data reveal statistically significant differences between variety of benign, dysplastic and malignant lesions, which could be used as fingerprints, applicable for differentiation algorithms. In a few of malignancies endogenous porphyrins signals were even observed, but in general the fluorescence signals were addressed to the coenzymes, such as NADH, flavins; structural proteins, such as collagen, elastin and their cross-links, as well as keratin in the case of basal cell lesions. Pigments, such as hemoglobin and melanin distorted the signal due to intrinsic fluorophores signal reabsorption, what has to be taken into account when the algorithms for discrimination of the pathology types are developed.
{"title":"Multispectral autoflourescence detection of skin neoplasia using steady-state techniques","authors":"E. Borisova, A. Gisbrecht, Tsanislava Genova-Hristova, P. Troyanova, E. Pavlova, N. Penkov, I. Bratchenko, V. Zakharov, Ilze Lihachova, I. Kuzmina, J. Spigulis","doi":"10.1117/12.2516337","DOIUrl":"https://doi.org/10.1117/12.2516337","url":null,"abstract":"In the current study were used excitation-emission matrices (EEMs) and synchronous fluorescence spectroscopy (SFS) steady-state techniques in a broad spectral regions (excitation at 220-500 nm and emission at 280-850 nm) to achieve the whole set of endogenous fluorophores, existed in normal and neoplastic cutaneous tissues. Several types of benign, dysplastic and malignant types of skin lesions were investigated ex vivo using both EEM and SFS modalities, namely the basal cell papilloma and carcinoma, pigmented nevi, dysplastic nevi, squamous cell carcinoma and malignant melanoma. Histological analysis was used as a “gold standard” for evaluation of clinical diagnosis of the lesions investigated. Comparison with the normal skin tissue spectral data was made, based on the signals detected from the safety margins areas of the surgically excised tumours. EEM and SFS data reveal statistically significant differences between variety of benign, dysplastic and malignant lesions, which could be used as fingerprints, applicable for differentiation algorithms. In a few of malignancies endogenous porphyrins signals were even observed, but in general the fluorescence signals were addressed to the coenzymes, such as NADH, flavins; structural proteins, such as collagen, elastin and their cross-links, as well as keratin in the case of basal cell lesions. Pigments, such as hemoglobin and melanin distorted the signal due to intrinsic fluorophores signal reabsorption, what has to be taken into account when the algorithms for discrimination of the pathology types are developed.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114565156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Atanasova, T. Dilova, A. Dikovska, G. Avdeev, P. Stefanov, N. Nedyalkov
In this work, we present fabrication of ZnO nanostructures by pulsed laser deposition in air at atmospheric pressure. The use of this technology leads to formation of nanostructures composed by nanoparticles and nanoaggregates. These nanostructures possess a large surface-to-volume ratio, which makes them suitable for gas-sensor application. The samples were exposed to NH3 and the effect was investigated of light irradiation on the gas response and recovery time of the sensor element. It was found that the response of the sensor element increases even by irradiation by sunlight. The gas sensing properties of the ZnO nanostructures were compared when irradiated by light of different wavelengths.
{"title":"Light irradiation effect on the gas sensing properties of the ZnO nanostructures","authors":"G. Atanasova, T. Dilova, A. Dikovska, G. Avdeev, P. Stefanov, N. Nedyalkov","doi":"10.1117/12.2516517","DOIUrl":"https://doi.org/10.1117/12.2516517","url":null,"abstract":"In this work, we present fabrication of ZnO nanostructures by pulsed laser deposition in air at atmospheric pressure. The use of this technology leads to formation of nanostructures composed by nanoparticles and nanoaggregates. These nanostructures possess a large surface-to-volume ratio, which makes them suitable for gas-sensor application. The samples were exposed to NH3 and the effect was investigated of light irradiation on the gas response and recovery time of the sensor element. It was found that the response of the sensor element increases even by irradiation by sunlight. The gas sensing properties of the ZnO nanostructures were compared when irradiated by light of different wavelengths.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114955852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The photo-excited luminescence response of solutions (in organic solvent) of eight selected organometallic coordination complexes of Iridium Ir(III) ion is studied upon irradiation with high-intensity short-pulse (nanosecond) ultraviolet laser irradiation, as well as by ultra-high-intensity ultrashort (femtosecond) laser pulses in the visible (violet). The Ir-complexes are cyclometalated and contain bis-phenylbenzothiazole as a main ligands and auxiliary β-diketone ligands, and they are intended to be used as luminescent materials and sensitive nanoprobes, e.g., in organic optoelectronics, sensorics, mechatronics and laser fluorescent microscopy. The results obtained by laser spectroscopy of dilute (10–5 M) solutions of the examined Ir-complexes show that they are efficient triplet emitters whose photo-excited emission is proper for fluorometric, optoelectronic and photonic applications.
{"title":"Luminescence of iridium complexes upon short laser pulses","authors":"N. Dimitrov, G. Hadjichristov, I. Stefanov","doi":"10.1117/12.2516653","DOIUrl":"https://doi.org/10.1117/12.2516653","url":null,"abstract":"The photo-excited luminescence response of solutions (in organic solvent) of eight selected organometallic coordination complexes of Iridium Ir(III) ion is studied upon irradiation with high-intensity short-pulse (nanosecond) ultraviolet laser irradiation, as well as by ultra-high-intensity ultrashort (femtosecond) laser pulses in the visible (violet). The Ir-complexes are cyclometalated and contain bis-phenylbenzothiazole as a main ligands and auxiliary β-diketone ligands, and they are intended to be used as luminescent materials and sensitive nanoprobes, e.g., in organic optoelectronics, sensorics, mechatronics and laser fluorescent microscopy. The results obtained by laser spectroscopy of dilute (10–5 M) solutions of the examined Ir-complexes show that they are efficient triplet emitters whose photo-excited emission is proper for fluorometric, optoelectronic and photonic applications.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116766257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Early diagnosis of pulp condition in cases of teeth with trauma is very important not only to preserve the vitality of the pulp but also to prevent both early and late traumatic complications. We investigated 120 frontal teeth with traumas. The teeth were tested on 1-st day, 15-th day, 30-th day, 3-rd month, 6-th month by pulse oximetry (PO) and electric pulp test (EPT). The results we received from pulse oximetry show that the saturation levels immediately after the trauma are very high, reaching 90%. Over the time, there has been a tendency for reduction of saturation, reaching a level of 82% by the 6th month, which is within the limit of the norm. The differences between the obtained saturation levels are statistically significant up to the 30th day of the trauma (p <0.05). The EPT results showed that the highest values were immediately after the trauma - 53 μA. The average values obtained for all periods up to and including 3-rd month are higher than the established norms. They differ statistically between each other and from the values, measured at 6-th month, which are average 8 μA. Comparing the circulatory response and the innervation of the traumatized teeth, we could conclude that the blood circulation recovers more quickly within one month, whereas the nerve conduction is restored until the 6-th month. Thus, the implementation of pulse oximetry in dentistry is of great benefit for the total pulp diagnosis – not only of the nerve, but also of the blood circulation.
{"title":"Six months follow-up with pulse oximetry and electric pulp test of teeth with trauma","authors":"D. Kosturkov, T. Uzunov","doi":"10.1117/12.2516147","DOIUrl":"https://doi.org/10.1117/12.2516147","url":null,"abstract":"Early diagnosis of pulp condition in cases of teeth with trauma is very important not only to preserve the vitality of the pulp but also to prevent both early and late traumatic complications. We investigated 120 frontal teeth with traumas. The teeth were tested on 1-st day, 15-th day, 30-th day, 3-rd month, 6-th month by pulse oximetry (PO) and electric pulp test (EPT). The results we received from pulse oximetry show that the saturation levels immediately after the trauma are very high, reaching 90%. Over the time, there has been a tendency for reduction of saturation, reaching a level of 82% by the 6th month, which is within the limit of the norm. The differences between the obtained saturation levels are statistically significant up to the 30th day of the trauma (p <0.05). The EPT results showed that the highest values were immediately after the trauma - 53 μA. The average values obtained for all periods up to and including 3-rd month are higher than the established norms. They differ statistically between each other and from the values, measured at 6-th month, which are average 8 μA. Comparing the circulatory response and the innervation of the traumatized teeth, we could conclude that the blood circulation recovers more quickly within one month, whereas the nerve conduction is restored until the 6-th month. Thus, the implementation of pulse oximetry in dentistry is of great benefit for the total pulp diagnosis – not only of the nerve, but also of the blood circulation.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125684455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Angelova, L. Slavov, G. Kolarov, I. Grigorov, C. Ghelev, L. Gurdev, I. Nedkov, D. Stoyanov
In this work some features are revealed, simultaneously by LIDAR and contact facilities, of the aerosol pollutions near high-traffic sites in Sofia City. Such features of interest are the extinction coefficient of the aerosol ensembles and their mass concentration, as well as the shapes and sizes and the structure of the aerosol particles and their chemical composition and biological content. They outline possible negative effects of the aerosol pollutants on the human health. The experiments are conducted in the spring and summer, in different sites of interest in Sofia City. The results about the aerosol mass concentration-to-extinction calibration of the LIDAR constant, obtained in the spring and in the late spring and the summer, are consistent with each other and with the combined spring-and-summer result. Using electron microscopy, various aerosol samples are visualized resembling mineral dust particles, pollen, soot, and even microorganisms. The results from the analysis of the images obtained would serve as guidelines of further chemical and microbiological studies.
{"title":"Lidar and contact investigations of aerosol characteristics near high traffic urban sites","authors":"R. Angelova, L. Slavov, G. Kolarov, I. Grigorov, C. Ghelev, L. Gurdev, I. Nedkov, D. Stoyanov","doi":"10.1117/12.2517934","DOIUrl":"https://doi.org/10.1117/12.2517934","url":null,"abstract":"In this work some features are revealed, simultaneously by LIDAR and contact facilities, of the aerosol pollutions near high-traffic sites in Sofia City. Such features of interest are the extinction coefficient of the aerosol ensembles and their mass concentration, as well as the shapes and sizes and the structure of the aerosol particles and their chemical composition and biological content. They outline possible negative effects of the aerosol pollutants on the human health. The experiments are conducted in the spring and summer, in different sites of interest in Sofia City. The results about the aerosol mass concentration-to-extinction calibration of the LIDAR constant, obtained in the spring and in the late spring and the summer, are consistent with each other and with the combined spring-and-summer result. Using electron microscopy, various aerosol samples are visualized resembling mineral dust particles, pollen, soot, and even microorganisms. The results from the analysis of the images obtained would serve as guidelines of further chemical and microbiological studies.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127113154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Bozhikoliev, K. Kovachev, A. Dakova, V. Slavchev, D. Dakova, L. Kovachev
Different kind of vortex structures of laser beam can be created by optical holograms and different optical masks. In the theory these vortices are solutions of the 2D scalar Leontovich equations. These solutions admit amplitude and phase singularities. The main tack of this work is to investigate the possibility of formation of vortex structures for narrow-band optical pulses, propagating in Kerr-type media. The evolution of such type of laser pulses is governed by nonlinear vector system of amplitude equations in second approximation of the linear dispersion. We found new class of analytical solutions with vortex structures. The nonlinear dispersion relations obtained by these vortex solutions show that their stability is due not only to balance between diffraction and nonlinearity, but also to a balance between non-linearity and angular distribution.
{"title":"Vortex solutions of vector nonlinear amplitude equations in optics","authors":"I. Bozhikoliev, K. Kovachev, A. Dakova, V. Slavchev, D. Dakova, L. Kovachev","doi":"10.1117/12.2519026","DOIUrl":"https://doi.org/10.1117/12.2519026","url":null,"abstract":"Different kind of vortex structures of laser beam can be created by optical holograms and different optical masks. In the theory these vortices are solutions of the 2D scalar Leontovich equations. These solutions admit amplitude and phase singularities. The main tack of this work is to investigate the possibility of formation of vortex structures for narrow-band optical pulses, propagating in Kerr-type media. The evolution of such type of laser pulses is governed by nonlinear vector system of amplitude equations in second approximation of the linear dispersion. We found new class of analytical solutions with vortex structures. The nonlinear dispersion relations obtained by these vortex solutions show that their stability is due not only to balance between diffraction and nonlinearity, but also to a balance between non-linearity and angular distribution.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"11047 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129505981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Based on our experience in the field of the interferential wedge, we present a new competitive application of such optical elements and structures built from them with theoretical description and experimental verification. We have demonstrated that a conventional interferential wedge or a structure of two wedges in compact layered implementation can be used as an attractive simple light power splitting element for a spatially and spectrally narrow light beam (basically a laser beam). The element can provide: 1) precisely and variably controlled ratio of the reflected and transmitted power by simple sliding in its plane of the list-like wedged structure with an apex angle of ~10-5 rad; 2) division practically without energy losses; 3) power ratio control without causing change of propagation direction of the reflected and the transmitted beams that is of essential interest for applications in optical schemes with complex geometry of the beams propagation; no optical properties variation of the reflective layers (mirrors) during the sliding; 4) working at beam power densities of MW/cm2 - GW /cm2 when the optical element is built from optical materials (layers) with high light damage resistivity.
{"title":"Interference wedged structures as light beam splitting elements","authors":"M. Deneva, M. Nenchev, E. Stoykova","doi":"10.1117/12.2516696","DOIUrl":"https://doi.org/10.1117/12.2516696","url":null,"abstract":"Based on our experience in the field of the interferential wedge, we present a new competitive application of such optical elements and structures built from them with theoretical description and experimental verification. We have demonstrated that a conventional interferential wedge or a structure of two wedges in compact layered implementation can be used as an attractive simple light power splitting element for a spatially and spectrally narrow light beam (basically a laser beam). The element can provide: 1) precisely and variably controlled ratio of the reflected and transmitted power by simple sliding in its plane of the list-like wedged structure with an apex angle of ~10-5 rad; 2) division practically without energy losses; 3) power ratio control without causing change of propagation direction of the reflected and the transmitted beams that is of essential interest for applications in optical schemes with complex geometry of the beams propagation; no optical properties variation of the reflective layers (mirrors) during the sliding; 4) working at beam power densities of MW/cm2 - GW /cm2 when the optical element is built from optical materials (layers) with high light damage resistivity.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"2 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131223866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Stoyanov, N. Gorunski, M. Zhekova, I. Stefanov, A. Dreischuh
Optical vortices (OVs) are the only known truly two-dimensional phase dislocations. Because of their spiral phase fronts, the OV interaction results, in the simplest case (when two OVs are presented), in vortex mutual attraction/repulsion or in OV pair rotation. In this work we provide experimental evidences that a stable elementary cell forming the base for a large optical vortex lattice can be created by situating equally and singly charged OVs in the apices of a triangle and square and by nesting an additional control OV with an opposite unit charge in the center of the structure. Experimental data for the rotation of these triangular and quadratic elementary cells vs. OV-to-OV separation as well as the rotation of the same structures vs. propagation distance are presented. Generation and stable propagation of large rigid square-shaped and hexagonal OV lattices is demonstrated.
{"title":"Vortex interactions revisited: Formation of stable elementary cells for creation of rigid vortex lattices","authors":"L. Stoyanov, N. Gorunski, M. Zhekova, I. Stefanov, A. Dreischuh","doi":"10.1117/12.2516531","DOIUrl":"https://doi.org/10.1117/12.2516531","url":null,"abstract":"Optical vortices (OVs) are the only known truly two-dimensional phase dislocations. Because of their spiral phase fronts, the OV interaction results, in the simplest case (when two OVs are presented), in vortex mutual attraction/repulsion or in OV pair rotation. In this work we provide experimental evidences that a stable elementary cell forming the base for a large optical vortex lattice can be created by situating equally and singly charged OVs in the apices of a triangle and square and by nesting an additional control OV with an opposite unit charge in the center of the structure. Experimental data for the rotation of these triangular and quadratic elementary cells vs. OV-to-OV separation as well as the rotation of the same structures vs. propagation distance are presented. Generation and stable propagation of large rigid square-shaped and hexagonal OV lattices is demonstrated.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"276 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115211216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nadia Hristova Aqakumova, V. Hadjimitova, K. Nikolova, S. Minkova, T. Evtimov, R. Gabrova, V. Vladev
The fluorescence spectra of Bulgarian and French wines of the same price class were obtained at excitation wavelengths of 265 nm, 275 nm and 295 nm. The excitation-emission matrices are obtained and compared. A correlation between the emission maxima and the anthocyanins or the antioxidant activity expressed in Trollox units is obtained.
{"title":"Comparative study of the characteristics of red Bulgarian and French wines using applied photonics methods","authors":"Nadia Hristova Aqakumova, V. Hadjimitova, K. Nikolova, S. Minkova, T. Evtimov, R. Gabrova, V. Vladev","doi":"10.1117/12.2520313","DOIUrl":"https://doi.org/10.1117/12.2520313","url":null,"abstract":"The fluorescence spectra of Bulgarian and French wines of the same price class were obtained at excitation wavelengths of 265 nm, 275 nm and 295 nm. The excitation-emission matrices are obtained and compared. A correlation between the emission maxima and the anthocyanins or the antioxidant activity expressed in Trollox units is obtained.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115293315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mineral aerosols from Sahara desert are frequently transported to Europe by regional or trans-continental air circulations. During such a long-range transport, Saharan dust is naturally mixed with other aerosols. The pathway of desert aerosols frequently passes over the Mediterranean Sea or the Atlantic Ocean. Under certain conditions, dust particles can blend with marine aerosols to form a mixture with specific volume/mass concentration and particle size distribution. These parameters are determinative for the climatologic, ecologic and medical impacts of the aerosols. Therefore, studies of desert-marine aerosols’ interacting and mixing are of considerable scientific and practical importance. In this work, we report results of lidar measurements and analysis of Saharan dust layers observed over Sofia, Bulgaria, possibly containing considerable amounts of marine aerosols captured and mixed with the dust particulate matter during the passage of air masses close to the surface of the Mediterranean Sea and/or Atlantic Ocean. The aerosol layer’s origin is proven by using air mass transport modeling and forecasting data. Measurements are carried out at two wavelengths (1064 nm and 532 nm) by means of the two aerosol channels of a lidar based on a frequency-doubled Nd:YAG laser. Topological, dynamical, optical, and microphysical properties of the dust/aerosol layers are studied and analyzed. Timeaveraged vertical profiles of the atmospheric backscattering coefficient at 1064 nm and 532 nm are presented. By using backscatter-related Ångström exponents, microphysical properties of aerosol particles are characterized qualitatively. Color map diagrams illustrate the temporal evolution of the aerosol density height distribution. Conclusions concerning the effects of dust mixing with marine aerosols are drawn.
{"title":"Saharan dust mixed with marine aerosols: lidar measurements and characterization","authors":"Z. Peshev, A. Deleva, T. Dreischuh","doi":"10.1117/12.2516543","DOIUrl":"https://doi.org/10.1117/12.2516543","url":null,"abstract":"Mineral aerosols from Sahara desert are frequently transported to Europe by regional or trans-continental air circulations. During such a long-range transport, Saharan dust is naturally mixed with other aerosols. The pathway of desert aerosols frequently passes over the Mediterranean Sea or the Atlantic Ocean. Under certain conditions, dust particles can blend with marine aerosols to form a mixture with specific volume/mass concentration and particle size distribution. These parameters are determinative for the climatologic, ecologic and medical impacts of the aerosols. Therefore, studies of desert-marine aerosols’ interacting and mixing are of considerable scientific and practical importance. In this work, we report results of lidar measurements and analysis of Saharan dust layers observed over Sofia, Bulgaria, possibly containing considerable amounts of marine aerosols captured and mixed with the dust particulate matter during the passage of air masses close to the surface of the Mediterranean Sea and/or Atlantic Ocean. The aerosol layer’s origin is proven by using air mass transport modeling and forecasting data. Measurements are carried out at two wavelengths (1064 nm and 532 nm) by means of the two aerosol channels of a lidar based on a frequency-doubled Nd:YAG laser. Topological, dynamical, optical, and microphysical properties of the dust/aerosol layers are studied and analyzed. Timeaveraged vertical profiles of the atmospheric backscattering coefficient at 1064 nm and 532 nm are presented. By using backscatter-related Ångström exponents, microphysical properties of aerosol particles are characterized qualitatively. Color map diagrams illustrate the temporal evolution of the aerosol density height distribution. Conclusions concerning the effects of dust mixing with marine aerosols are drawn.","PeriodicalId":355156,"journal":{"name":"International School on Quantum Electronics: Laser Physics and Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129551227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：