Photoluminescence and Charge
... was synthesized using methods described elsewhere.22 Calixarene 3 was synthesized via sulfonation and subsequent nitration23 of detert-butylated 1.24 Calixarene 4 was synthesized via base-catalyzed condensation of tert-butyl phenol with elemental sulfur.25 Calixarene 6 was synthesized from 1 and iod ...
... was synthesized using methods described elsewhere.22 Calixarene 3 was synthesized via sulfonation and subsequent nitration23 of detert-butylated 1.24 Calixarene 4 was synthesized via base-catalyzed condensation of tert-butyl phenol with elemental sulfur.25 Calixarene 6 was synthesized from 1 and iod ...
Appendix
... the uncertainty in the sample's mass and the uncertainty of the volumetric glassware. We did not consider other sources of uncertainty, including the purity of the Cu wire, the effect of temperature on the volumetric glassware, and the repeatability of our measurements. In this appendix we take a mo ...
... the uncertainty in the sample's mass and the uncertainty of the volumetric glassware. We did not consider other sources of uncertainty, including the purity of the Cu wire, the effect of temperature on the volumetric glassware, and the repeatability of our measurements. In this appendix we take a mo ...
Chapter 36 . Optical Properties of Semiconductors
... hence support and complement chemical and elemental analyses; and (9) finally, most optical techniques are ‘‘table-top’’ procedures that can be implemented by semiconductor device manufacturers at a reasonable cost. All optical measurements of semiconductors rely on a fundamental understanding of th ...
... hence support and complement chemical and elemental analyses; and (9) finally, most optical techniques are ‘‘table-top’’ procedures that can be implemented by semiconductor device manufacturers at a reasonable cost. All optical measurements of semiconductors rely on a fundamental understanding of th ...
Association of Nitrate Ion with Metal Cations in Aqueous Solution: a
... The unknown matrices E and C cannot be computed from the results of PCA alone, some additional information is needed. Since the extent of ion association monotonically increases with increasing salt concentration, it follows that in the cases considered here the total salt concentration, c, can serv ...
... The unknown matrices E and C cannot be computed from the results of PCA alone, some additional information is needed. Since the extent of ion association monotonically increases with increasing salt concentration, it follows that in the cases considered here the total salt concentration, c, can serv ...
Carbon Dating Method
... 14C mixes with earth surface material in cyclic modes; the cycle time determines the average abundances of 14C in material. Small fraction of 0.7 tons 14C is average amount in atmosphere, fast mixing (10 years cycle time) with surface water by evaporation processes and rain warrants similar abundanc ...
... 14C mixes with earth surface material in cyclic modes; the cycle time determines the average abundances of 14C in material. Small fraction of 0.7 tons 14C is average amount in atmosphere, fast mixing (10 years cycle time) with surface water by evaporation processes and rain warrants similar abundanc ...
Few-cycle terahertz generation and spectroscopy of nanostructures
... a wavelength of the incident light. An absolute maximum is achieved for a layer with an optical thickness of 54 λo . At this thickness the absorption reaches more than 90% for an absorption coefficient of α = 1.335 × 104 cm−1 in GaAs at 800 nm (Palik 1985). This value is larger than that achievable fo ...
... a wavelength of the incident light. An absolute maximum is achieved for a layer with an optical thickness of 54 λo . At this thickness the absorption reaches more than 90% for an absorption coefficient of α = 1.335 × 104 cm−1 in GaAs at 800 nm (Palik 1985). This value is larger than that achievable fo ...
Variable Incidence Angle Fluorescence Interference Contrast
... indicative of some variation in thickness arising from the etch process. The SiO2 thickness determined by ellipsometry is therefore reported to 1 nm. To narrow and vary the range of excitation uincs, the aperture diaphragm of a Nikon E800 epifluorescence microscope was replaced by a photomask that o ...
... indicative of some variation in thickness arising from the etch process. The SiO2 thickness determined by ellipsometry is therefore reported to 1 nm. To narrow and vary the range of excitation uincs, the aperture diaphragm of a Nikon E800 epifluorescence microscope was replaced by a photomask that o ...
Noise analysis of spectrometers based on speckle pattern
... is diffusive), enabling high resolution with a compact size. Recently, a random photonic nanostructure was used to develop a spectrometer on a silicon chip, where the trade-off between resolution and footprint is particularly restrictive [4]. The speckle pattern generated by interference of waveguid ...
... is diffusive), enabling high resolution with a compact size. Recently, a random photonic nanostructure was used to develop a spectrometer on a silicon chip, where the trade-off between resolution and footprint is particularly restrictive [4]. The speckle pattern generated by interference of waveguid ...
Raman Spectroscopy: Introductory Tutorial
... • A vibrational spectroscopy - IR and Raman are the most common vibrational spectroscopies for assessing molecular motion and fingerprinting species - Based on inelastic scattering of a monochromatic excitation source - Routine energy range: 200 - 4000 cm–1 ...
... • A vibrational spectroscopy - IR and Raman are the most common vibrational spectroscopies for assessing molecular motion and fingerprinting species - Based on inelastic scattering of a monochromatic excitation source - Routine energy range: 200 - 4000 cm–1 ...
Chemistry_Stoichiome..
... c) both (ii) and (iii) are correct d) both (i) and (ii) are correct 31. Density of dry air containing only N2 & O2 is 1.15 g/L at 740 mm and 300 K. What is % composition of N2 by weight in the air? a) 78 % b) 75.5 % c) 72.91 % d) 72.75 % 32. A gaseous mixture of H2 and CO2 gas contains 66 mass % of ...
... c) both (ii) and (iii) are correct d) both (i) and (ii) are correct 31. Density of dry air containing only N2 & O2 is 1.15 g/L at 740 mm and 300 K. What is % composition of N2 by weight in the air? a) 78 % b) 75.5 % c) 72.91 % d) 72.75 % 32. A gaseous mixture of H2 and CO2 gas contains 66 mass % of ...
Excited-State Intramolecular Proton Transfer in 3
... complex, a dimer, or a conformer of 3-HF with a high barrier to ESIPT. We believe that an impurity can be excluded as the source of violet emission since essentially the same spectra are obtained when 3-HF purified only by recrystallization from methanol, or even not purified at all, was used. Howev ...
... complex, a dimer, or a conformer of 3-HF with a high barrier to ESIPT. We believe that an impurity can be excluded as the source of violet emission since essentially the same spectra are obtained when 3-HF purified only by recrystallization from methanol, or even not purified at all, was used. Howev ...
from unt.edu - Department of Chemistry
... An especially intriguing class of linear-chain species involves trinuclear d10 complexes, which have garnered considerable interest in recent years owing in large part to their fascinating luminescence properties. For example, Balch and coworkers reported that a trinuclear carbeniate Au(I) complex e ...
... An especially intriguing class of linear-chain species involves trinuclear d10 complexes, which have garnered considerable interest in recent years owing in large part to their fascinating luminescence properties. For example, Balch and coworkers reported that a trinuclear carbeniate Au(I) complex e ...
2 - Durham Research Online
... In low viscosity media, the fluorescence from a DADQ adduct is very weak with photoluminescence quantum yields (PLQY) in the range of 10-2 – 10-3. Increasing the viscosity and/or lowering the temperature results in a dramatically increased PLQY and increased fluorescence lifetime from the ps to the ...
... In low viscosity media, the fluorescence from a DADQ adduct is very weak with photoluminescence quantum yields (PLQY) in the range of 10-2 – 10-3. Increasing the viscosity and/or lowering the temperature results in a dramatically increased PLQY and increased fluorescence lifetime from the ps to the ...
The shock tube as wave reactor for kinetic studies and material
... mention a few, techniques like interferometric, emission or absorption of molecules in the infrared, visible or ultraviolet spectral regions have been tried out before the more sensitive atomic resonance absorption spectroscopy (ARAS) and laser based diagnostic techniques emerged on the scene. The s ...
... mention a few, techniques like interferometric, emission or absorption of molecules in the infrared, visible or ultraviolet spectral regions have been tried out before the more sensitive atomic resonance absorption spectroscopy (ARAS) and laser based diagnostic techniques emerged on the scene. The s ...
Get
... developed based on the CW laser sources [14–18]. In order to improve the scan frequency precision of laser and detection sensitivity, Hodges et al. proposed a frequency stabilized cavity ringdown spectroscopy (FS-CRDS), in which the length of ringdown cavity was stabilized to an external absolute fr ...
... developed based on the CW laser sources [14–18]. In order to improve the scan frequency precision of laser and detection sensitivity, Hodges et al. proposed a frequency stabilized cavity ringdown spectroscopy (FS-CRDS), in which the length of ringdown cavity was stabilized to an external absolute fr ...
A very convenient setup to generate intense VUV coherent light at
... (ii) On the contrary, sum generation at 125.053 nm corresponds to a region of negative dispersion. It may provide a straightforward example to check, experimentally and theoretically various parameters of F W SF M processes which can be optimized to yield the maximum attainable conversion efficiency. ...
... (ii) On the contrary, sum generation at 125.053 nm corresponds to a region of negative dispersion. It may provide a straightforward example to check, experimentally and theoretically various parameters of F W SF M processes which can be optimized to yield the maximum attainable conversion efficiency. ...
Theoretical derivation of the depth average of remotely sensed
... MERIS. Such inversions do not take into account the vertical structure of the parameters. Especially in the coastal zones, there can be significant stratification, however. The remote sensing reflectance at the surface thus incorporates aspects of the vertical structure of the optical properties. Th ...
... MERIS. Such inversions do not take into account the vertical structure of the parameters. Especially in the coastal zones, there can be significant stratification, however. The remote sensing reflectance at the surface thus incorporates aspects of the vertical structure of the optical properties. Th ...
CHAPTER 4 Fiber optic III: attenuation and dispersion
... In the UV region absorption occurs when a photon excites an electron of the valence band to a higher energy level. In the IR region, absorption occurs due to resonant vibration of atomic bonds in the fibre. ...
... In the UV region absorption occurs when a photon excites an electron of the valence band to a higher energy level. In the IR region, absorption occurs due to resonant vibration of atomic bonds in the fibre. ...
Femtosecond powder diffraction with a laser-driven hard X
... A multilayer X-ray optic focuses the X-rays emitted in forward direction onto the powder sample. The optic collects X-rays in a solid angle of approximately 10−4 , resulting in a X-ray flux of 106 photons per seconds on the sample. The X-ray spot size on the sample is between 30 to 200 μ m (FWHM), d ...
... A multilayer X-ray optic focuses the X-rays emitted in forward direction onto the powder sample. The optic collects X-rays in a solid angle of approximately 10−4 , resulting in a X-ray flux of 106 photons per seconds on the sample. The X-ray spot size on the sample is between 30 to 200 μ m (FWHM), d ...
Laser cooling in thulium-doped solids
... Stirling cycle coolers can reach temperatures of order 10 K but are relatively large and cause vibrations that are problematic for many applications such as focal-plane sensor elements. Optical coolers do not have this problem and cause low electromagnetic interference in the region of cooling. They ...
... Stirling cycle coolers can reach temperatures of order 10 K but are relatively large and cause vibrations that are problematic for many applications such as focal-plane sensor elements. Optical coolers do not have this problem and cause low electromagnetic interference in the region of cooling. They ...
Glossary of terms used in photocatalysis and radiation catalysis
... The same convention as in the “Glossary of terms used in photochemistry” [7] was adopted regarding the magnitudes implying energy or photons incident on a surface from all directions, i.e., the set of symbols included in the IUPAC “Green Book” [9], and recommended by the International Commission on ...
... The same convention as in the “Glossary of terms used in photochemistry” [7] was adopted regarding the magnitudes implying energy or photons incident on a surface from all directions, i.e., the set of symbols included in the IUPAC “Green Book” [9], and recommended by the International Commission on ...
Optical Comms 2004 (Summer)
... Absorption of light caused by impurities in the fibre, such as water and metals ions. One of the most common impurities is dissolved water in the glass, present as the hydroxyl or OH ion. In this case the fundamental processes takes place between 2700 nm and 4200 nm, but gives rise to so called abso ...
... Absorption of light caused by impurities in the fibre, such as water and metals ions. One of the most common impurities is dissolved water in the glass, present as the hydroxyl or OH ion. In this case the fundamental processes takes place between 2700 nm and 4200 nm, but gives rise to so called abso ...
Visible Light Generation of Iodine Atoms and I
... MLCT excited state was dynamically quenched by iodide with Ksv ) 1.1 × 105 M-1 and kq ) 6.6 ( 0.3 × 1010 M-1 s-1, a value consistent with diffusion-limited electron transfer. Excited state hole transfer to iodide was quantitative but the product yield was low due to poor cage escape yields, φCE ) 0. ...
... MLCT excited state was dynamically quenched by iodide with Ksv ) 1.1 × 105 M-1 and kq ) 6.6 ( 0.3 × 1010 M-1 s-1, a value consistent with diffusion-limited electron transfer. Excited state hole transfer to iodide was quantitative but the product yield was low due to poor cage escape yields, φCE ) 0. ...
Aims - Publikationsserver der Universität Regensburg
... The spectral sensitivity of the photoreceptors is determined by the absorption region of the active chromophores. Specially four classes of blue light photoreceptors have been identified, they are PYP, BLUF-proteins, phototropins, and cryptochromes. BLUF-proteins, phototropins, and cryptochromes are ...
... The spectral sensitivity of the photoreceptors is determined by the absorption region of the active chromophores. Specially four classes of blue light photoreceptors have been identified, they are PYP, BLUF-proteins, phototropins, and cryptochromes. BLUF-proteins, phototropins, and cryptochromes are ...
Dialysis Guide_scienova
... Concentration of substance The dialysis speed depends on the concentration gradient, which is highest at the start of dialysis. Through the dialysis process the concentration gradient between the ...
... Concentration of substance The dialysis speed depends on the concentration gradient, which is highest at the start of dialysis. Through the dialysis process the concentration gradient between the ...
Atomic absorption spectroscopy
Atomic absorption spectroscopy (AAS) is a spectroanalytical procedure for the quantitative determination of chemical elements using the absorption of optical radiation (light) by free atoms in the gaseous state.In analytical chemistry the technique is used for determining the concentration of a particular element (the analyte) in a sample to be analyzed. AAS can be used to determine over 70 different elements in solution or directly in solid samples used in pharmacology, biophysics and toxicology research.Atomic absorption spectroscopy was first used as an analytical technique, and the underlying principles were established in the second half of the 19th century by Robert Wilhelm Bunsen and Gustav Robert Kirchhoff, both professors at the University of Heidelberg, Germany.The modern form of AAS was largely developed during the 1950s by a team of Australian chemists. They were led by Sir Alan Walsh at the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Division of Chemical Physics, in Melbourne, Australia.Atomic absorption spectrometry has many uses in different areas of chemistry such as: Clinical analysis: Analyzing metals in biological fluids and tissues such as whole blood, plasma, urine, saliva, brain tissue, liver, muscle tissue, semen Pharmaceuticals: In some pharmaceutical manufacturing processes, minute quantities of a catalyst that remain in the final drug product Water analysis: Analyzing water for its metal content.↑ ↑ ↑