L. Angeli, C. Arias, G. Cristoforetti, C. Fabbri, S. Legnaioli, V. Palleschi, G. Radi, A. Salvetti, E. Tognoni
In the field of cultural heritage, the study of the materials used by the artist is useful both for the knowledge of the artwork and for conservation and restoring interventions. In this communication, we present results of some decorations analysis obtained by the use of two complementary laser techniques: micro-LIBS and micro-Raman spectroscopy. With both techniques it is possible to operate in a practically nondestructive way on the artwork itself, without sampling or pretreatment. Micro-Raman spectroscopy gives information on the molecular structure of the pigments used, while micro-LIBS can give quantitative information about the elemental composition of the same materials. In this paper, qualitative results are reported obtained on the study of some Neolithic potteries coming from the archaeological site of Trasano (Matera); the fragments show decorations in different colors, red, black, and white. The aim of the study was detecting whether the colored decorations were made by using added pigments or came from the manufacturing process.
{"title":"Spectroscopic techniques applied to the study of Italian painted Neolithic Potteries","authors":"L. Angeli, C. Arias, G. Cristoforetti, C. Fabbri, S. Legnaioli, V. Palleschi, G. Radi, A. Salvetti, E. Tognoni","doi":"10.1155/2006/61607","DOIUrl":"https://doi.org/10.1155/2006/61607","url":null,"abstract":"In the field of cultural heritage, the study of the materials used by the artist is useful both for the knowledge of the artwork and for conservation and restoring interventions. In this communication, we present results of some decorations analysis obtained by the use of two complementary laser techniques: micro-LIBS and micro-Raman spectroscopy. With both techniques it is possible to operate in a practically nondestructive way on the artwork itself, without sampling or pretreatment. Micro-Raman spectroscopy gives information on the molecular structure of the pigments used, while micro-LIBS can give quantitative information about the elemental composition of the same materials. In this paper, qualitative results are reported obtained on the study of some Neolithic potteries coming from the archaeological site of Trasano (Matera); the fragments show decorations in different colors, red, black, and white. The aim of the study was detecting whether the colored decorations were made by using added pigments or came from the manufacturing process.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115810517","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}
K. Melessanaki, C. Stringari, C. Fotakis, D. Anglos
We present results from preliminary laser cleaning studies performed on a 20th century modern painting, in which laser-induced breakdown spectroscopy (LIBS) was employed for monitoring the progress of material removal. This synergistic approach, that combines laser ablation cleaning with spectroscopic control, is of obvious importance as it offers a reliable means of ensuring proper conservation and could be the basis of a standard protocol for laser-based restoration procedures.
{"title":"Laser Cleaning and Spectroscopy: A Synergistic Approach in the Conservation of a Modern Painting","authors":"K. Melessanaki, C. Stringari, C. Fotakis, D. Anglos","doi":"10.1155/2006/42709","DOIUrl":"https://doi.org/10.1155/2006/42709","url":null,"abstract":"We present results from preliminary laser cleaning studies performed on a 20th century modern painting, in which laser-induced breakdown spectroscopy (LIBS) was employed for monitoring the progress of material removal. This synergistic approach, that combines laser ablation cleaning with spectroscopic control, is of obvious importance as it offers a reliable means of ensuring proper conservation and could be the basis of a standard \u0000protocol for laser-based restoration procedures.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"31 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120982788","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}
This work offers an automatic identification system of Raman spectra of artistic pigments. The proposed methodology is based on a fuzzy logic system, and uses principal component analysis to reduce redundancies in data and the correlation operator as an index of similarity between two Raman spectra. Moreover, as sometimes pigments are used in mixtures by artist, the designed system is able to recognize binary mixtures of pigments on the basis of their Raman fingerprints.
{"title":"Automatic Identification of Artistic Pigments by Raman Spectroscopy Using Fuzzy Logic and Principal Component Analysis","authors":"M. Castanys, M. Soneira, R. Pérez-Pueyo","doi":"10.1155/2006/18792","DOIUrl":"https://doi.org/10.1155/2006/18792","url":null,"abstract":"This work offers an automatic identification system of Raman spectra of artistic pigments. The proposed methodology is based on a fuzzy logic system, and uses principal component analysis to reduce redundancies in data and the correlation operator as an index of similarity between two Raman spectra. Moreover, as sometimes pigments are used in mixtures by artist, the designed system is able to recognize binary mixtures of pigments on the basis of their Raman fingerprints.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121761238","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}
M. Gora, M. Pircher, E. Götzinger, T. Bajraszewski, M. Strlič, J. Kolar, C. Hitzenberger, P. Targowski
A novel application of Optical Coherence Tomography utilizing infrared light of 830 nm central wavelength for non invasive examination of the structure of parchment, some covered with iron gall ink, is presented. It is shown that both the parchment and the ink applied are sufficiently transparent to light of this wavelength. In the study, Spectral OCT (SOCT) as well as Polarisation Sensitive OCT (PS-OCT) techniques were used to obtain cross-sectional images of samples of parchment based on scattering properties. The second technique was additionally employed to recover the birefringence properties and the optical axis orientations of the sample. It was shown that freshly produced parchment exhibits a degree of birefringence. However, this property declines with ageing, and samples of old parchment completely depolarise the incident light.
{"title":"Optical Coherence Tomography for Examination of Parchment Degradation","authors":"M. Gora, M. Pircher, E. Götzinger, T. Bajraszewski, M. Strlič, J. Kolar, C. Hitzenberger, P. Targowski","doi":"10.1155/2006/68679","DOIUrl":"https://doi.org/10.1155/2006/68679","url":null,"abstract":"A novel application of Optical Coherence Tomography utilizing infrared light of 830 nm central wavelength for non invasive examination of the structure of parchment, some covered with iron gall ink, is presented. It is shown that both the parchment and the ink applied are sufficiently transparent to light of this wavelength. In the study, Spectral OCT (SOCT) as well as Polarisation Sensitive OCT (PS-OCT) techniques were used to obtain cross-sectional images of samples of parchment based on scattering properties. The second technique was additionally employed to recover the birefringence properties and the optical axis orientations of the sample. It was shown that freshly produced parchment exhibits a degree of birefringence. However, this property declines with ageing, and samples of old parchment completely depolarise the incident light.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127060163","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. Bordalo, P. J. Morais, H. Gouveia, Christina Young
The application of laser cleaning to paintings is relatively recent despite its use on stone-based materials for over 30 years. The cleaning of paintings is of high importance, because it is the least reversible invasive intervention, as well as the most usual of all conservation treatments. Paintings are multilayer system of heterogeneous nature, often very sensitive and inherent difficult to clean. Being a noncontact method, laser cleaning has advantages compared to alternative techniques. Over the last decade, there have been important research studies and advances. However, they are far from sufficient to study the effects on painting materials and to establish the best parameters for each material under investigation. This paper presents a historical overview of the application of laser technology to the cleaning of paintings giving special emphasis on the research of the last decade. An overview of the current research into the interaction between the radiation and the different painting materials (varnish, pigments, and medium) is also given. The pigment's mechanisms of discoloration and the presence of media as a variable factor in the discoloration of pigments are discussed.
{"title":"Laser Cleaning of Easel Paintings: An Overview","authors":"R. Bordalo, P. J. Morais, H. Gouveia, Christina Young","doi":"10.1155/2006/90279","DOIUrl":"https://doi.org/10.1155/2006/90279","url":null,"abstract":"The application of laser cleaning to paintings is relatively recent despite its use on stone-based materials for over 30 years. The cleaning of paintings is of high importance, because it is the least reversible invasive intervention, as well as the most usual of all conservation treatments. Paintings are multilayer system of heterogeneous nature, often very sensitive and inherent difficult to clean. Being a noncontact method, laser cleaning has advantages compared to alternative techniques. Over the last decade, there have been important research studies and advances. However, they are far from sufficient to study the effects on painting materials and to establish the best parameters for each material under investigation. This paper presents a historical overview of the application of laser technology to the cleaning of paintings giving special emphasis on the research of the last decade. An overview of the current research into the interaction between the radiation and the different painting materials (varnish, pigments, and medium) is also given. The pigment's mechanisms of discoloration and the presence of media as a variable factor in the discoloration of pigments are discussed.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134316772","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}
A. Siatou, D. Charalambous, V. Argyropoulos, P. Pouli
This paper is focused on the systematic investigation of the layer-by-layer removal of corrosion products on artificially corroded metal coupons aiming to introduce a methodology for the optimum laser cleaning approach of historical metal objects. Thus, it is very important to determine the chemical composition of the studied surfaces before and after irradiation. A series of laser cleaning studies has been performed on test coupons (reference and artificially corroded). Wavelength and pulse duration effects are investigated. Initial studies were focused on the use of infrared (1064 nm) and ultraviolet (355 nm and 248 nm) radiations of nanosecond (ns) pulse duration. Damage and removal threshold values were determined for the substrates and the corrosion layers, respectively. The irradiated surfaces are evaluated microscopically under the optical and the scanning electron microscope, while the mineralogical and chemical composition of the various layers is determined with X-ray diffraction and SEM-EDAX analyses, respectively. The results obtained are providing a comprehensive approach for understanding the main mechanisms that are significant in the different laser cleaning regimes, while the optimum cleaning methodologies for the studied materials are being established.
{"title":"A Comprehensive Study for the Laser Cleaning of Corrosion Layers due to Environmental Pollution for Metal Objects of Cultural Value: Preliminary Studieson Artificially Corroded Coupons","authors":"A. Siatou, D. Charalambous, V. Argyropoulos, P. Pouli","doi":"10.1155/2006/85324","DOIUrl":"https://doi.org/10.1155/2006/85324","url":null,"abstract":"This paper is focused on the systematic investigation of the layer-by-layer removal of corrosion products on artificially corroded metal coupons aiming to introduce a \u0000methodology for the optimum laser cleaning approach of historical metal objects. Thus, it is very important to determine the chemical composition of the studied surfaces before and after irradiation. A series of laser cleaning studies has been performed on test coupons (reference and artificially corroded). Wavelength and pulse duration effects are investigated. Initial studies were focused on the use of infrared (1064 nm) and \u0000ultraviolet (355 nm and 248 nm) radiations of nanosecond (ns) pulse duration. Damage and removal threshold values were determined for the substrates and the corrosion layers, respectively. The irradiated surfaces are evaluated microscopically under the optical and the scanning electron microscope, while the mineralogical and chemical composition of the various layers is determined with X-ray diffraction and SEM-EDAX analyses, respectively. The results obtained are providing a comprehensive approach for understanding the main mechanisms that are significant in the different laser \u0000cleaning regimes, while the optimum cleaning methodologies for the \u0000studied materials are being established.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133774412","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}
Changes of the elemental composition due to laser surface cleaning of a naturally crusted historical sandstone were investigated by means of the SEM/EDX technique. Data obtained for stone samples prior to and after laser irradiation were compared with those for noncrusted, reference ones. It has been observed that the crust removal resulting from ablative cleaning was accompanied by a decrease of the partial content of elements Al, S, K, Ca, and Mg in the range of 60–80 % of their initial value recorded for the noncleaned, crust-covered stone surface. In the stone layer just under the crust coverage, a structure characterized by intergranular spaces between the SiO 2 grains being the main sandstone component filled with degraded binder was observed. From the coincidence of the binder destruction and chemical composition of the crust, the stone surface destruction due to the long-term interaction of environmental pollution was deduced. The spatial distributions of individual elements obtained by mapping after laser irradiation indicated that besides SiO 2 the content of elemental components in the sandstone surface layer decreased by 50 % , whereas for Fe with the initial content of 4 % and other surface remnants: P, Ti, Zn, and Cl—all below 1 % , insignificant changes were only revealed. It was concluded in agreement with the literature that surface cleaning by means of the 1064 nm laser does not cause removal of iron from the sandstone surface.
{"title":"Observation of the Laser Cleaning Effect on the Gotland Sandstone Elemental Composition","authors":"M. Jasińska, J. Bredal-Jørgensen, G. Śliwiński","doi":"10.1155/2006/84781","DOIUrl":"https://doi.org/10.1155/2006/84781","url":null,"abstract":"Changes of the elemental composition due to laser surface cleaning of a naturally crusted historical sandstone were investigated by means of the SEM/EDX technique. Data obtained for stone samples prior to and after laser irradiation were compared with those for noncrusted, reference ones. It has been observed that the crust removal resulting from ablative cleaning was accompanied by a decrease of the partial content of elements Al, S, K, Ca, and Mg in the range of 60–80 % of their initial value recorded for the noncleaned, crust-covered stone surface. In the stone layer just under the crust coverage, a structure characterized by intergranular spaces between the SiO 2 grains being the main sandstone component filled with degraded binder was observed. From the coincidence of the binder destruction and chemical composition of the crust, the stone surface destruction due to the long-term interaction of environmental pollution was deduced. The spatial distributions of individual elements \u0000obtained by mapping after laser irradiation indicated that besides SiO 2 the content of elemental components in the sandstone surface layer decreased by 50 % , whereas for Fe with the initial content of 4 % and other surface remnants: P, Ti, Zn, and Cl—all below 1 % , insignificant changes were only revealed. It was concluded in agreement with the literature that surface cleaning by means of the 1064 nm laser does not cause removal of iron from the sandstone surface.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122879126","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}
Yaoqun Li, Shin-ya Sasaki, Takanori Inoue, T. Ogawa
A sensitive comparative fluorescence microscopic approach was developed and used to study the water at the air-water interface region. An insoluble chromophore mesoc-α,β,γ,δ-tetraphenylporphine (TPP) was spread on the water. Its fluorescence spectrum indicated that the spectrum of TPP on the water surface was similar to those measured in nonpolar hydrocarbon solvents. Thus, the water at the surface was concluded to be hydrophobic and less polar than the water in the bulk.
{"title":"Hydrophobicity of water at the surface as studied by laser-induced fluorescence microscopy","authors":"Yaoqun Li, Shin-ya Sasaki, Takanori Inoue, T. Ogawa","doi":"10.1155/1998/57838","DOIUrl":"https://doi.org/10.1155/1998/57838","url":null,"abstract":"A sensitive comparative fluorescence microscopic approach was developed and used to \u0000study the water at the air-water interface region. An insoluble chromophore mesoc-α,β,γ,δ-tetraphenylporphine (TPP) was spread on the water. Its fluorescence spectrum \u0000indicated that the spectrum of TPP on the water surface was similar to those measured in \u0000nonpolar hydrocarbon solvents. Thus, the water at the surface was concluded to be \u0000hydrophobic and less polar than the water in the bulk.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132846426","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}
This paper presents an overview of data obtained on the intramolecular vibrational energy distribution in infrared multiphoton excited CF2HCl, CF2Cl2, SF6 and CH3CHF2. All but CF2HCl show collisionless changes in the intensity of the spontaneous Raman signals after excitation, indicating that the excitation alters the population in the Raman active modes. A comparison of the spectrally integrated intensities of the Raman signals yields information on the distribution of vibrational energy over the modes of the molecule. The results for CF2Cl2 show a nonthermal distribution of energy after the excitation.
{"title":"Raman spectroscopy of infrared multiphoton excited molecules","authors":"Jyhpyng Wang, Kuei-Hsien Chen, E. Mazur","doi":"10.1155/LC.8.97","DOIUrl":"https://doi.org/10.1155/LC.8.97","url":null,"abstract":"This paper presents an overview of data obtained on the intramolecular vibrational energy distribution in infrared multiphoton excited CF2HCl, CF2Cl2, SF6 and CH3CHF2. All but CF2HCl show collisionless changes in the intensity of the spontaneous Raman signals after excitation, indicating that the excitation alters the population in the Raman active modes. A comparison of the spectrally integrated intensities of the Raman signals yields information on the distribution of vibrational energy over the modes of the molecule. The results for CF2Cl2 show a nonthermal distribution of energy after the excitation.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131837863","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}
P. Bado, P. H. Berens, J. Bergsma, M. Coladonato, C. Dupuy
We hope to answer one of the most fundamental and important unsolved questions in chemistry: how, from a molecular perspective, do chemical reactions in solution actually occur. The key to solving this long-standing problem is to understand the molecular dynamics, i.e., the motions of the atoms and the forces that drive them. We have already developed theoretical techniques and computational procedures involving specialized computer hardware needed to calculate the molecular dynamics for many chemical reactions in solution. From the dynamics we have derived the interface for experimental verification, namely transient electronic, infrared, and Raman spectra as well as X-ray diffraction, all of which are potentially observable manifestations of the atomic motions during the reaction. We have tested our approach on the simple inorganic I2 photodissociation and solvent caging reaction. The agreement between molecular dynamics based theory and experimental picosecond transient electronic absorption spectrum as a function of solvent, time, and wavelength is sufficiently close as to indicate that for the first time we are discovering at least part of the molecular dynamics by which a real solution chemical reaction takes place.
{"title":"Molecular Dynamics of Chemical Reactions in Solution","authors":"P. Bado, P. H. Berens, J. Bergsma, M. Coladonato, C. Dupuy","doi":"10.1155/LC.3.231","DOIUrl":"https://doi.org/10.1155/LC.3.231","url":null,"abstract":"We hope to answer one of the most fundamental and important unsolved questions \u0000in chemistry: how, from a molecular perspective, do chemical reactions in solution \u0000actually occur. The key to solving this long-standing problem is to understand the \u0000molecular dynamics, i.e., the motions of the atoms and the forces that drive them. We \u0000have already developed theoretical techniques and computational procedures involving \u0000specialized computer hardware needed to calculate the molecular dynamics for many \u0000chemical reactions in solution. From the dynamics we have derived the interface for \u0000experimental verification, namely transient electronic, infrared, and Raman spectra as \u0000well as X-ray diffraction, all of which are potentially observable manifestations of the \u0000atomic motions during the reaction. We have tested our approach on the simple \u0000inorganic I2 photodissociation and solvent caging reaction. The agreement between \u0000molecular dynamics based theory and experimental picosecond transient electronic \u0000absorption spectrum as a function of solvent, time, and wavelength is sufficiently close \u0000as to indicate that for the first time we are discovering at least part of the molecular \u0000dynamics by which a real solution chemical reaction takes place.","PeriodicalId":296295,"journal":{"name":"Laser Chemistry","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1985-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125900724","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}
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