The open spectroscopy journal最新文献

Optimal Conditions for a Multimode Laser Diode with Delayed Optical Feedback in Terahertz Time-Domain Spectroscopy 太赫兹时域光谱中延迟光反馈多模激光二极管的最佳条件

The open spectroscopy journal Pub Date : 2023-11-04 DOI: 10.3390/spectroscj1030012

Kenji Wada, Tokihiro Kitagawa, Tetsuya Matsuyama, Koichi Okamoto, Fumiyoshi Kuwashima

{"title":"Optimal Conditions for a Multimode Laser Diode with Delayed Optical Feedback in Terahertz Time-Domain Spectroscopy","authors":"Kenji Wada, Tokihiro Kitagawa, Tetsuya Matsuyama, Koichi Okamoto, Fumiyoshi Kuwashima","doi":"10.3390/spectroscj1030012","DOIUrl":"https://doi.org/10.3390/spectroscj1030012","url":null,"abstract":"Recent studies have indicated that terahertz time-domain spectroscopy (THz-TDS) can stably and efficiently acquire output spectra using an affordable and compact multimode laser diode (MMLD) with delayed optical feedback as the light source. This research focused on a numerical analysis of the optimal conditions for employing an MMLD with delayed optical feedback (a chaotic oscillating laser diode) in THz-TDS utilizing multimode rate equations. The findings revealed that the intermittent chaotic output generated by the MMLD, characterized by concurrent picosecond pulse oscillations lasting several tens of picoseconds, proved to be highly effective for THz-TDS. By appropriately setting the amounts for the injection current and optical feedback and the delay time for the optical feedback, intermittent chaotic oscillation could be attained within a considerably broad parameter range. The generation of intermittent chaotic oscillations was confirmed by observing their characteristic asymmetric spectral shapes. Moreover, both the MMLD output spectrum and the THz-TDS output spectrum exhibited consistently stable shapes at the microsecond scale, demonstrating the attractor properties inherent in an MMLD with delayed optical feedback.","PeriodicalId":88758,"journal":{"name":"The open spectroscopy journal","volume":"40 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135773999","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}

引用次数: 0

A Spectroscopy-Based Multi-Analytical Approach for Studies in Conservation: Decorations in the Alexander Palace (Tsarskoye Selo) 基于光谱学的多分析方法研究亚历山大宫(Tsarskoye Selo)装饰的保存

The open spectroscopy journal Pub Date : 2023-10-20 DOI: 10.3390/spectroscj1030011

Marilena Ricci, Federico Sebastiani, Maurizio Becucci, Mikhail Rogozny, Vadim Parfenov

{"title":"A Spectroscopy-Based Multi-Analytical Approach for Studies in Conservation: Decorations in the Alexander Palace (Tsarskoye Selo)","authors":"Marilena Ricci, Federico Sebastiani, Maurizio Becucci, Mikhail Rogozny, Vadim Parfenov","doi":"10.3390/spectroscj1030011","DOIUrl":"https://doi.org/10.3390/spectroscj1030011","url":null,"abstract":"We studied the painted decorations found during recent restoration work in the Alexander Palace in Tsarskoye Selo. Optical/laser spectroscopic methods were applied to obtain a characterization of the materials, pigments, and binders in use and, possibly, their degradation. We analyzed samples of the original Art Nouveau style decoration that was detached in 2019 during conservation work at the State Office of Emperor Nicholas II. A combination of Raman microscopy, infrared spectroscopy, and elemental analysis (obtained from the optical emission following laser plasma formation) allowed us to obtain detailed information on the materials used. The precious pigments of the artist’s green-blue palette and the binder used (drying oil) were identified. A mixture of blue (Prussian blue and ultramarine blue), white (lead white and barium white), and yellow (chrome yellow and zinc yellow) pigments determined the different blue hues used. The use of bronze paint in the dark blue area, which was identified as a brass powder applied with a drying oil as a binder, was also demonstrated.","PeriodicalId":88758,"journal":{"name":"The open spectroscopy journal","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135569207","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}

引用次数: 0

Rotational Isomerism of the Side Chains of Hydroxypropyl Cellulose in Aqueous Solution Observed Using Attenuated Total Reflectance Infrared Spectroscopy 用衰减全反射红外光谱法观察水溶液中羟丙基纤维素侧链的旋转异构现象

The open spectroscopy journal Pub Date : 2023-10-13 DOI: 10.3390/spectroscj1030010

Mark A. Davies

引用次数: 0

Effect of Alkaline Salts on Pyrolyzed Solid Wastes in Used Edible Oils: An Attenuated Total Reflectance Analysis of Surface Compounds as a Function of the Temperature 碱性盐对废弃食用油中热解固体废物的影响:表面化合物随温度变化的衰减全反射分析

The open spectroscopy journal Pub Date : 2023-09-13 DOI: 10.3390/spectroscj1020009

Francisca Romero-Sarria, Concepción Real, José Manuel Córdoba, María Carmen Hidalgo, María Dolores Alcalá

{"title":"Effect of Alkaline Salts on Pyrolyzed Solid Wastes in Used Edible Oils: An Attenuated Total Reflectance Analysis of Surface Compounds as a Function of the Temperature","authors":"Francisca Romero-Sarria, Concepción Real, José Manuel Córdoba, María Carmen Hidalgo, María Dolores Alcalá","doi":"10.3390/spectroscj1020009","DOIUrl":"https://doi.org/10.3390/spectroscj1020009","url":null,"abstract":"Biochars obtained via the pyrolysis of biomass are very attractive materials from the point of view of their applications and play key roles in the current energy context. The characterization of these carbonaceous materials is crucial to determine their field of application. In this work, the pyrolysis of a non-conventional biomass (solid wastes in used edible oils) was investigated. The obtained biochars were characterized using conventional techniques (TG, XRD, and SEM-EDX), and a deep analysis via ATR-FTIR was performed. This spectroscopic technique, which is a rapid and powerful tool that is well adapted to study carbon-based materials, was employed to determine the effect of temperature on the nature of functional groups on the surface. Moreover, the water washing of the raw sample (containing important quantities of inorganic salts) before pyrolysis evidenced that the inorganic salts act as catalysts in the biomass degradation and influence the degree of condensation (DOC) of PAH. Moreover, it was observed that these salts contribute to the retention of oxygenated compounds on the surface of the solid.","PeriodicalId":88758,"journal":{"name":"The open spectroscopy journal","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135739857","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}

引用次数: 0

Narrow-Linewidth Pr:YLF Laser for High-Resolution Raman Trace Gas Spectroscopy 用于高分辨率拉曼痕量气体光谱的窄线宽Pr:YLF激光器

The open spectroscopy journal Pub Date : 2023-08-23 DOI: 10.3390/spectroscj1020008

Charuka Muktha Arachchige, A. Muller

引用次数: 0

Dielectric Stability of Triton X-100-Based Tissue-Mimicking Materials for Microwave Imaging 基于Triton x -100的微波成像组织模拟材料介电稳定性研究

The open spectroscopy journal Pub Date : 2023-08-03 DOI: 10.3390/spectroscj1020007

Mariana Relva, S. Devesa

{"title":"Dielectric Stability of Triton X-100-Based Tissue-Mimicking Materials for Microwave Imaging","authors":"Mariana Relva, S. Devesa","doi":"10.3390/spectroscj1020007","DOIUrl":"https://doi.org/10.3390/spectroscj1020007","url":null,"abstract":"Microwave imaging is an emerging technology, and has been proposed for various applications, namely as an alternative diagnostic technology. Microwave imaging explores the dielectric contrast of target tissues, enabling diagnosis based on the differences in dielectric properties between healthy and diseased tissues, with low cost, portability and non-ionizing radiation as its main advantages, constituting an alternative to various imaging technologies for diagnosing and monitoring. Before clinical trials of microwave imaging devices for the study of dielectric properties, phantoms are used, mimicking the materials of tissues and simulating the electric properties of human tissues, for device validation. The purpose of this work was to prepare and perform dielectric characterization of mimicking materials for the development of an anthropomorphic phantom of the human ankle with realistic dielectric and anatomic properties. The biological tissues targeted in this investigation were the skin, muscle, cortical bone, trabecular bone and fat, with the mimicking materials prepared using Triton X-100, sodium chloride and distilled water. The dielectric characterization was performed using a coaxial probe, operating at frequencies between 0.5 and 4.0 GHz. Since the stability of the dielectric properties of mimicking materials is one of their main properties, the dielectric characterization was repeated after 15 and 35 days.","PeriodicalId":88758,"journal":{"name":"The open spectroscopy journal","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77707898","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}

引用次数: 0

Barrier to Methyl Internal Rotation and Equilibrium Structure of 2-Methylthiophene Determined by Microwave Spectroscopy 微波光谱法测定2-甲基噻吩的甲基内旋势和平衡结构

The open spectroscopy journal Pub Date : 2023-05-30 DOI: 10.3390/spectroscj1010005

Kenneth J. Koziol, Hamza El Hadki, Arne Lüchow, Natalja Vogt, Jean Demaison, Ha Vinh Lam Nguyen

{"title":"Barrier to Methyl Internal Rotation and Equilibrium Structure of 2-Methylthiophene Determined by Microwave Spectroscopy","authors":"Kenneth J. Koziol, Hamza El Hadki, Arne Lüchow, Natalja Vogt, Jean Demaison, Ha Vinh Lam Nguyen","doi":"10.3390/spectroscj1010005","DOIUrl":"https://doi.org/10.3390/spectroscj1010005","url":null,"abstract":"The microwave spectrum of 2-methylthiophene was recorded in a frequency range from 2 to 26.5 GHz using a molecular-jet Fourier transform microwave spectrometer with a Fabry–Pérot type resonator chamber and coaxial arrangement of the resonator and the molecular beam. Measuring and assigning spectra of the 34S and 13C isotopologues allowed the determination of the semiexperimental equilibrium structure (reSE). Comparing the structure to that of thiophene revealed a decrease in the ∠(S−C2−C3) angle from 111.595(6)° to 111.37(1)° by addition of the methyl group to the C(2) position, as well as an increase in the S−C2 bond length from 1.7102(1) Å to 1.7219(2) Å. A–E splittings from internal rotation of the methyl group were observed, and the V3 potential in the vibrational ground state was determined to be 197.7324(18) cm−1. The V3 value and the rotational constants A, B, C were calculated with a large number of different methods and basis sets for benchmarking purposes by comparing them to the fitted parameters. The V3 value was also compared to those of other thiophene and furan derivatives to gain a better understanding of the steric and electrostatic effects in these classes of compounds.","PeriodicalId":88758,"journal":{"name":"The open spectroscopy journal","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135478173","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}

引用次数: 1

The open spectroscopy journal Pub Date : 2023-04-24 DOI: 10.3390/spectroscj1010004

Cláudia Martins, I. Almeida, S. Rebelo, S. Magalhães, A. Nunes

{"title":"Age-Related Fourier-Transform Infrared Spectroscopic Changes in Protein Conformation in an Aging Model of Human Dermal Fibroblasts","authors":"Cláudia Martins, I. Almeida, S. Rebelo, S. Magalhães, A. Nunes","doi":"10.3390/spectroscj1010004","DOIUrl":"https://doi.org/10.3390/spectroscj1010004","url":null,"abstract":"The loss of proteostasis, which results in the accumulation of misfolded proteins, is one of the hallmarks of aging and is frequently associated with the aging process. Fibroblasts are a cellular model widely used in the study of aging and can mimic the loss of proteostasis that occurs in the human body. When studying human aging using fibroblasts, two approaches can be used: fibroblasts from the same donor aged in vitro until senescence or fibroblasts from donors of different ages. A previous study by our group showed that the first approach can be used in the study of aging. Thus, this work aimed to study the spectroscopic profile of human dermal fibroblasts from four donors of different ages using Fourier-transform infrared spectroscopy to identify changes in protein conformation and to compare results with those obtained in the previous study. Partial least squares regression analysis and peak intensity analysis suggested that fibroblasts from older donors were characterized by an increase in the levels of antiparallel β-sheets and a decrease in intermolecular β-sheets, in agreement with our previous results.","PeriodicalId":88758,"journal":{"name":"The open spectroscopy journal","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89840415","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}

引用次数: 2

Diode Laser Overtone Spectroscopy of Methyl Iodide at 850 nm 850 nm处碘化甲酯的二极管激光泛音光谱

The open spectroscopy journal Pub Date : 2023-04-11 DOI: 10.3390/spectroscj1010003

A. Lucchesini

引用次数: 0

Interpreting the Microwave Spectra of Diatomic Molecules 解释双原子分子的微波光谱

The open spectroscopy journal Pub Date : 2023-02-08 DOI: 10.3390/spectroscj1010002

C. Pye

引用次数: 0