- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2019 21st International Conference on Transparent Optical Networks (ICTON) - Angers, France (2019.7.9-2019.7.13)] 2019 21st International Conference on Transparent Optical Networks (ICTON) - As-Se-Te Planar Waveguides Prepared by Continuous and Femtosecond Laser Writing
摘要： As a result of the previous experiments [1], it was found that the Te-based chalcogenide films prepared by plasma deposition have a transparency window in the range from 1.2 to 19 μm and can be modified in the two-photon absorption mode, and in the linear absorption mode only the thermal effects were observed leading to crystallization of the films or their destruction. In this work, PECVD-prepared As-Se-Te films were modified by continuous laser irradiation of different wavelengths – 473, 632.8 and 808 nm. For the modification, samples with compositions As40Se50Te10 and As40Se44Te16 were deposited on a substrate of epi-polished crystalline sapphire. This paper presents the results of studying of the effect of continuous laser radiation on the optical and structural properties of the chalcogenide films samples. Also, planar waveguided structures based on the As-Se-Te films were formed and investigated.
关键词： planar waveguides,continuous laser writing,arsenic selenide films
更新于2025-09-12 10:27:22
-
Effect of arsenic coordination state on the structure, aromaticity, and optical properties of dithieno[3,2-b:2’,3’-d]arsoles
摘要： A silylated derivative of 4-phenyl-dithieno[3,2-b:2’,3’-d]arsole (DTAs) was synthesized, and the effect of coordinating of DTAs compounds to Pd on their structural and optical properties was investigated. Coordination of the As to Pd was found to increase the structural aromaticity of the ring system as measured by the harmonic oscillator measure of heterocyclic electron delocalization (HOMHED), and the pyramidalization of the As atoms was also found to show a good correlation with the HOMHED values. However, coordination had a more subtle impact on the optical properties than seen for phosphorus-containing analogues as the metal-ligand interactions were weaker.
关键词： aromaticity,arsenic,palladium complex,luminescence,dithienoarsole
更新于2025-09-10 09:29:36
-
Identification of donor deactivation centers in heavily As-doped Si using time-of-flight medium-energy ion scattering spectroscopy
摘要： Electrically-inactive arsenic (As) complexes in silicon are investigated using time-of-flight medium-energy ion scattering spectroscopy. In heavily As-doped Si, the As atoms that are segregated in the Si interface region just below the SiO2 are found to be in interstitial forms (Asi), while the As atoms in the bulk Si region are found to be in the substitutional form (AsSi). Despite the substitutional form of As, most of the As are found to be electrically inactive in the bulk region, and we identify the As to be in the form of a h111i-oriented AsSi-Si-vacancy (AsSi-VSi) complex. The Asi atoms in the interface Si region are found to exist together with Si-interstitial atoms (Sii), suggesting that the Asi atoms in the interface Si region accompany the Sii atoms.
关键词： silicon,electrical deactivation,arsenic,doping,ion scattering spectroscopy
更新于2025-09-10 09:29:36
-
Nanocomposites-based nitrated polyethersulfone and doped ZnYNiO for selective As <sup>3+</sup> sensor application
摘要： The contamination of arsenic (As3+) cation in drinking water is one of the most well-known sources for human arsenic poison. Due to its high toxicity to human, there is a need to develop an efficient and low-cost method to detect it in aquatic environment. A sensor of nitrated polyethersulfone (PES-NO2) doped with ZnYNiO nanocomposites was successfully fabricated. PES-NO2 was synthesized in this study using H2SO4: HNO3 while ZnYNiO nanoparticles were fabricated using wet-chemical technique under low temperature and basic condition. The results of Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) analysis did confirm the interactions between the doped nanoparticles and nitro functions grafted on PES backbone. The developed polymeric nanocomposite (PES-NO2-ZnYNiO) was then used as a superb coating sensor for As3+. The working electrode of desire heavy metal ion sensor was fabricated by glassy carbon electrode (GCE) coated with PES-NO2-ZnYNiO nanocomposites as layer of thin film. To estimate the cationic sensor performances, a calibration curve obtained from current versus electrolyte (selective As3+ ion) concentration relation was plotted. The linearity of calibration curve is found over the linear dynamic range (LDR) of 0.1 nM~0.1 mM. The slope of calibration curve is used to measure the sensitivity and detection limit (DL) of As3+ cation sensor, and these are 9.8101 μA μM?1 cm?2 and 96.77 ± 4.84 pM, respectively. Therefore, the As3+ ion sensor is found as selective with good sensitivity, reproducible with high accuracy, validated in real environmental samples, long-term stability in aqueous medium, and highly active with short response time.
关键词： arsenic sensor,sensitivity,characterization,electrochemical method,synthesis,ZnYNiO,environmental safety,nitrated polyethersulfone
更新于2025-09-10 09:29:36
-
Evaluating Leaf and Canopy Reflectance of Stressed Rice Plants to Monitor Arsenic Contamination
摘要： Arsenic contamination is a serious problem in rice cultivated soils of many developing countries. Hence, it is critical to monitor and control arsenic uptake in rice plants to avoid adverse effects on human health. This study evaluated the feasibility of using re?ectance spectroscopy to monitor arsenic in rice plants. Four arsenic levels were induced in hydroponically grown rice plants with application of 0, 5, 10 and 20 μmol¨ L′1 sodium arsenate. Re?ectance spectra of upper fully expanded leaves were acquired over visible and infrared (NIR) wavelengths. Additionally, canopy re?ectance for the four arsenic levels was simulated using SAIL (Scattering by Arbitrarily Inclined Leaves) model for various soil moisture conditions and leaf area indices (LAI). Further, sensitivity of various vegetative indices (VIs) to arsenic levels was assessed. Results suggest that plants accumulate high arsenic amounts causing plant stress and changes in re?ectance characteristics. All leaf spectra based VIs related strongly with arsenic with coef?cient of determination (r2) greater than 0.6 while at canopy scale, background re?ectance and LAI confounded with spectral signals of arsenic affecting the VIs’ performance. Among studied VIs, combined index, transformed chlorophyll absorption re?ectance index (TCARI)/optimized soil adjusted vegetation index (OSAVI) exhibited higher sensitivity to arsenic levels and better resistance to soil backgrounds and LAI followed by red edge based VIs (modi?ed chlorophyll absorption re?ectance index (MCARI) and TCARI) suggesting that these VIs could prove to be valuable aids for monitoring arsenic in rice ?elds.
关键词： SAIL model,spectral re?ectance,vegetative indices,arsenic uptake,leaf chlorophyll,red edge,plant stress,soil re?ectance,LAI,rice
更新于2025-09-09 09:28:46
-
Study of dry‐ and wet‐process amorphous arsenic sulfides: Synthesis, Raman reference spectra, and identification in historical art materials
摘要： This paper reports the dry and wet synthetic procedures and characterization by Raman spectroscopy of amorphous arsenic sulfide reference pigments. Reference spectra of two amorphous materials obtained by wet process methods and four dry process references of amorphous arsenic sulfide pigments of known composition are presented and discussed. While all materials present a main band characteristic for the amorphous pigment centered on 341 cm?1, additional small contributions indicate the presence of sulfur, arsenic oxide, and crystalline nano phases embedded in the amorphous matrix. Although only the broad 341‐cm?1 peak is necessary to identify the arsenic sulfide as an amorphous material, the smaller additional features allow for the characterization of the various manufacturing processes and initial materials used. In ideal conditions, these small features also enable to assess the As/S ratio of the studied amorphous arsenic sulfide pigments based on their relative intensity. In this context, the latter reference spectra were used to characterize the amorphous arsenic sulfide pigments and their arsenic to sulfur elemental composition in four 18th‐ to 20th‐century historical samples and compared with scanning electron microscopy with energy dispersive X‐ray semiquantitative analyses. The identification of the amorphous arsenic sulfide used in these historical samples was compared with the description of the manufacturing processes reported in historical sources of the time, allowing for a better understanding of the evolution of the amorphous arsenic sulfide pigments manufacturing methods.
关键词： reference spectra,cultural heritage,pigment characterization,synthesis,amorphous arsenic sulfide
更新于2025-09-09 09:28:46
-
Atomically Thin 2D‐Arsenene by Liquid‐Phased Exfoliation: Toward Selective Vapor Sensing
摘要： Phosphorene and antimonene, single- or few-layered (FL) semiconductor materials, have recently attracted enormous attention due to their unique properties, provided by their extreme thinness. Here, a liquid-phase exfoliation (LPE) procedure to prepare FL arsenene, another member of pnictogens, assisted by sonication and without any additional surfactant is reported. The exfoliation process is performed in various solvents. Among those, N-methylpyrrolidone is found to provide the highest concentration of stable arsenene sheets. Spectroscopic and microscopic analyses confirm the formation of high-quality few-layer arsenene nanosheets with large lateral dimensions. An application of this material for construction of vapor sensor based on electrochemical impedance spectroscopy is demonstrated. The device detects selectively methanol or acetone vapors depending on the selected resonance frequency. The results are highly reproducible, and the vapor sensor has long-term stability.
关键词： centrifugation,arsenic,2D arsenene,vapor sensors,liquid-phase exfoliation
更新于2025-09-04 15:30:14