PREPARATION AND PROPERTIES OF CRYSTALLINE CANDIDIN

1956 ◽  
Vol 34 (9) ◽  
pp. 1163-1167 ◽  
Author(s):  
L. C. Vining ◽  
W. A. Taber
Keyword(s):  
Absorption Maximum ◽  
Visible Region ◽  
Crystalline Form ◽  
Molecular Formula ◽  
Amino Group ◽  
Equivalent Weight ◽  
Conjugated Diene ◽  
Antifungal Antibiotic ◽  
Infrared Spectral ◽  
Best Fit

Candidin, the antifungal antibiotic produced by Streptomycesviridoflavus, has been isolated in crystalline form. Analyses and equivalent weight values best fit a molecular formula C46H75NO17. The substance is amphoteric and probably contains one carboxyl and one amino group. Infrared spectral evidence also indicates a polyhydroxylated structure, and the absorption in the visible region shows the presence of a conjugated heptaene chromophore. An additional conjugated diene elsewhere in the molecule is suggested by hydrogenation values and the absorption maximum at 228 mμ.

scholarly journals Big Three Dragons: A [N ii] 122 μm Constraint and New Dust-continuum Detection of a z = 7.15 Bright Lyman-break Galaxy with ALMA

2021 ◽  
Vol 923 (1) ◽  
pp. 5
Author(s):  
Yuma Sugahara ◽  
Akio K. Inoue ◽  
Takuya Hashimoto ◽  
Satoshi Yamanaka ◽  
Seiji Fujimoto ◽  
...  
Keyword(s):  
Spectral Energy Distribution ◽  
Far Infrared ◽  
Abundance Ratio ◽  
Continuum Emission ◽  
Spectral Energy ◽  
High Ionization ◽  
The Galaxy ◽  
Infrared Spectral ◽  
Best Fit ◽  
Redshift Galaxies

Abstract We present new Atacama Large Millimeter/submillimeter Array Band 7 observational results of a Lyman-break galaxy at z = 7.15, B14-65666 (“Big Three Dragons”), which is an object detected in [O iii] 88 μm, [C ii] 158 μm, and dust continuum emission during the epoch of reionization. Our targets are the [N ii] 122 μm fine-structure emission line and the underlying 120 μm dust continuum. The dust continuum is detected with a ∼19σ significance. From far-infrared spectral energy distribution sampled at 90, 120, and 160 μm, we obtain a best-fit dust temperature of 40 K (79 K) and an infrared luminosity of log 10 ( L IR / L ⊙ ) = 11.6 (12.1) at the emissivity index β = 2.0 (1.0). The [N ii] 122 μm line is not detected. The 3σ upper limit of the [N ii] luminosity is 8.1 × 107 L ⊙. From the [N ii], [O iii], and [C ii] line luminosities, we use the Cloudy photoionization code to estimate nebular parameters as functions of metallicity. If the metallicity of the galaxy is high (Z > 0.4 Z ⊙), the ionization parameter and hydrogen density are log 10 U ≃ − 2.7 ± 0.1 and n H ≃ 50–250 cm−3, respectively, which are comparable to those measured in low-redshift galaxies. The nitrogen-to-oxygen abundance ratio, N/O, is constrained to be subsolar. At Z < 0.4 Z ⊙, the allowed U drastically increases as the assumed metallicity decreases. For high ionization parameters, the N/O constraint becomes weak. Finally, our Cloudy models predict the location of B14-65666 on the BPT diagram, thereby allowing a comparison with low-redshift galaxies.

OPTICAL SPECTROSCOPY AND NONLINEAR TRANSMITTANCE STUDY OF FULLERENE C60 IN MIXTURES WITH 2-CYCLOOCTYLAMINO-5-NITROPYRIDINE (COANP)

2004 ◽  
Vol 13 (01) ◽  
pp. 113-127 ◽  
Author(s):  
SERGEY S. SARKISOV ◽  
ELENA I. RADOVANOVA ◽  
BURL H. PETERSON ◽  
ALEX LEYDERMAN ◽  
MICHAEL CURLEY ◽  
...  
Keyword(s):  
Optical Properties ◽  
Absorption Spectrum ◽  
Optical Absorption ◽  
Infrared Absorption ◽  
Chemical Bonding ◽  
Infrared Absorption Spectrum ◽  
Visible Region ◽  
Fullerene C60 ◽  
Amino Group

Characterization of the infrared absorption spectrum of the solutions of fullerene C 60 with 2-cyclooctylamino-5-nitropyridine additive has been performed with the focus on possible bonding with the amino-group of the additive. No occurrence of such bonding was found at normal conditions. Also no change of optical absorption in visible region and optical limiting of fullerene due to chemical bonding with the additive was detected. The resulting optical properties of the mixture were simply a sum of the properties of the components for a molar proportion of the additive to fullerene approaching 200:1.

Growth and Magneto-Optical Properties of CaTbAlO4 Crystal

2011 ◽  
Vol 306-307 ◽  
pp. 1722-1727 ◽  
Author(s):  
Man Mei ◽  
Li Li Cao ◽  
Yan He ◽  
Ru Ru Zhang ◽  
Fei Yun Guo ◽  
...  
Keyword(s):  
Optical Properties ◽  
Single Crystal ◽  
Room Temperature ◽  
Near Infrared ◽  
Visible Region ◽  
Czochralski Method ◽  
Optical Devices ◽  
X Ray Diffraction ◽  
X Ray ◽  
Infrared Spectral

The calcium terbium aluminate (CaTbAlO4) single crystal was grown by Czochralski method successfully for the first time.The structure of the crystal was determined by X-ray diffraction analysis.The transmission spectrum of the crystal was measured at room temperature at the wavelength of 400-1500nm.The specific Faraday rotation of the single crystal was surveyed at room temperature at the wavelength 532nm, 633nm, and 1064nm respectively.The Verdet constants of the CaTbAlO4 crystal are calculated and the results show that the Verdet constants of CaTbAlO4 are around 110% higher than that of TGG in the visible and near-infrared spectral region.Therefore,crystal CaTbAlO4 can be promising material for the fabrication of magneto-optical devices in the visible region.

Vulcanization Chemistry

1985 ◽  
Vol 58 (2) ◽  
pp. 284-294 ◽  
Author(s):  
E. Morita ◽  
A. B. Sullivan ◽  
A. Y. Coran
Keyword(s):  
Weight Basis ◽  
Equal Weight ◽  
Amino Group ◽  
Triazine Ring ◽  
Equivalent Weight ◽  
Hydrogen Atoms ◽  
Sulfur Vulcanization ◽  
Diene Rubbers ◽  
The Ideal

Abstract Prevulcanization inhibitors based on triazines can be prepared. In each case the triazine ring is amino-substituted such that one or two of the amino hydrogen atoms per amino-group are alkylthio- or arylthio-substituted. The new triazine-derived prevulcanization inhibitors are extremely active in accelerated sulfur vulcanization of diene rubbers (e.g., NR or SBR). Differing accelerators or accelerator systems may require different triazine-derived prevulcanization inhibitors for best results. Provided that the reactivity of the inhibitor is sufficiently near the ideal, its weight-basis activity is greatest when its equivalent weight per S—N bond is least. Overall, hexakis(cyclohexylthio)melamine and especially hexakis(isopropylthio)melamine are the most effective premature vulcanization inhibitors tested, on an equal-weight basis.

scholarly journals A Convenient Synthesis and Spectral Studies of Diamines Derivatives

2021 ◽  
Author(s):  
Sudershan Reddy Gondi ◽  
Michael B. Jacobsson ◽  
Christiana Julia Rissing ◽  
David Y. Son
Keyword(s):  
Electron Transfer ◽  
Absorption Maximum ◽  
Steric Effect ◽  
Amide Group ◽  
Spectral Studies ◽  
Amino Group ◽  
Absorption Properties ◽  
Convenient Synthesis

<div>A new series of substituted anthranilic esters derivatives linked with a 1,3-dithiolane and</div><div>benzyloximino moiety was synthesized using the simple esterfication reaction and products were</div><div>fully characterized. The isolated yields of these compounds range from 59 to 96%. 1,3-</div><div>dithiolane ester and the benzyloxy substituted diamine derivatives are white solids and stable to</div><div>air and moisture. The synthesized compounds can be exhibits UV-vis absorption properties by</div><div>their structures with a amine or amide group, It is observed that absorption maximum is excellent</div><div>for 2,6-disubstituted benzyloxy esters which can be explained by electron transfer or conjugation</div><div>is steric effect in ortho substitution from the amino group and the amide group.</div>

Resonance Raman in platinum phthalocyanine

1978 ◽  
Vol 56 (7) ◽  
pp. 976-984 ◽  
Author(s):  
Tzer-Hsiang Huang ◽  
Klaus E. Rieckhoff ◽  
Eva-Maria Voigt
Keyword(s):  
Absorption Maximum ◽  
Lower Energy ◽  
Mixed Solvents ◽  
Resonance Raman ◽  
Visible Region ◽  
Excited Singlet ◽  
Absorption Region ◽  
The Third ◽  
Resonance Raman Spectra ◽  
Platinum Phthalocyanine

The resonance Raman spectra and excitation profiles of platinum phthalocyanine (PtPc) in α-chloronaphthalene (α-ClN) and in mixtures of α-ClN and n-octane were obtained at 295 K with excitation from 660 to 570 nm covering the total lower energy absorption region of PtPc. Eighteen fundamentals and overtone-combinations were observed. Our data show that the third absorption maximum of PtPc in the visible region is actually the (0–1), but not the (0–2) as previously interpreted, transition. The (0–1) bands in the excitation profiles of most resonance-enhanced-vibrations were found to be more intense and frequency shifted compared with their counterparts in absorption. Based on the depolarization ratios, we deduced the symmetry of PtPc in α-ClN in the excited singlets to be D2h, C2v, or D2; no differences were found in the mixed solvents. The small Stokes loss observed in the absorption spectra, as well as the absence of the (0–2) maxima in the excitation profiles, indicate that the equilibrium position of the first excited singlet is only slightly different from that of the ground state.

Alkyllithium-Initiated Polymerization of Trans-1,3,5-Hexatriene and Copolymerization with Styrene

1989 ◽  
Vol 62 (2) ◽  
pp. 332-342 ◽  
Author(s):  
Roderic P. Quirk ◽  
Rajeev Bhatia
Keyword(s):  
Branched Polymers ◽  
General Effect ◽  
Block Copolymerization ◽  
Conjugated Diene ◽  
Polymer Backbone ◽  
Spectral Analyses ◽  
Effect Of Solvent ◽  
Hydrocarbon Solvents ◽  
Infrared Spectral ◽  
Conjugated Trienes

Abstract The results reported herein established the complexity of the alkyllithium-initiated anionic homopolymerization, styrene copolymerization and styrene block copolymerization of 1,3,5-hexatriene in comparison to the controlled, predictable behavior observed with dienes. As a result of 1,6- and 1,2-enchainment, conjugated diene units are formed along the polymer backbone which can react with the living carbanionic centers to produce branched polymers as indicated in Equation (1). The general effect of solvent on microstructure, as indicated by infrared spectral analyses, is analogous to that of dienes in that 1,2-addition is increased in polar versus hydrocarbon solvents. The observation of branching reactions suggests that conjugated trienes may be useful as branching agents for copolymerizations or linking reactions analogous to the behavior of divinylbenzenes.

scholarly journals Enhanced Removal of Metal Ions from Water by Novel Composite Magnesia-Amended Silica Granules

2009 ◽  
Vol 27 (4) ◽  
pp. 383-394
Author(s):  
P. Y. Zhu ◽  
H.Z. Wang ◽  
X. Li ◽  
X.F. Tang
Keyword(s):  
Silicon Dioxide ◽  
Metal Ions ◽  
Contact Time ◽  
Ph Value ◽  
Weak Acid ◽  
Adsorption Processes ◽  
Infrared Spectral ◽  
Removal Of Metal ◽  
Removal Of Metal Ions ◽  
Best Fit

The potential of a novel sorbent, magnesia-amended silica granules (MAS), for the removal of metal ions from aqueous solution has been examined. MAS, prepared by calcining magnesium chloride-impregnated silicon dioxide at 773 K, exhibited an adsorption capacity towards metal ions that was 15- to 30-times larger than that of silicon dioxide. Batch sorption studies were performed as a function of contact time and pH. X-Ray powder diffraction (XRD), infrared spectral analysis (FT-IR), porosity and surface area measurements were used to characterize the physicochemical properties of MAS. At an initial concentration of 50 mg/ℓ, more than 90% removal of metal ions was achieved within 8 h contact time at a weak acid pH value. Of the kinetic models tested, the pseudo-second-order model gave the best fit to the kinetic data, while the Langmuir isotherm model provided the best fit to the equilibrium adsorption data for metal ions onto MAS. The adsorption processes were endothermic.

scholarly journals Study the fluorescent and conductivity properties of a 4-hydroxy-3-nitro-1,8-naphthalic anhydride

2021 ◽  
Vol 2063 (1) ◽  
pp. 012025
Author(s):  
Roza Al-Aqar
Keyword(s):  
Ionic Conductivity ◽  
Absorption Maximum ◽  
Fluorescence Spectra ◽  
Visible Region ◽  
Emission Spectra ◽  
Solvent Polarity ◽  
Disulfonic Acid ◽  
Absorption And Fluorescence Spectra ◽  
Naphthalic Anhydride ◽  
Fluorescence Maximum

Abstract The compound of (4-hydroxy-3-nitro-1,8-naphthalic anhydride) and the dopant material (4-hydroxy-m-benzene-disulfonic acid) were synthesized. The UV-Vis absorption and fluorescence spectra of the compound were recorded. The bathochromic shifts in absorption due to the changes in the solvent polarity was observed, in DMSO solvent, the compound shows different peaks, three bands in the UV region and one band in the visible region, one absorption peak at 402 nm, which might be attributed to the (ICT) band. The emission spectra of this compound were sensitive to the solvent polarity. They moved to lower energies with increasing the polarity of the solvent. The influence of the solvent polarity on the fluorescence maximum was more pronounced compared with the absorption maximum, showing ca. 3 nm red shift on moving from butanol to DMSO. The effect of the dopant material on the conductivities (ionic and specific) of the compound was studied, the ionic conductivity was increased as the weight of the dopant material increases, and the ionic conductivity (G) was measured in water as a solvent. the (G) of the compound was 2.4X10-6 Siemens at 0.01 gm of the dopant material, and was 2.62X10-4 Siemens after the dopant material was added (0.1 gm).

scholarly journals A Convenient Synthesis and Spectral Studies of Diamines Derivatives

2021 ◽  
Author(s):  
Sudershan Reddy Gondi ◽  
Michael B. Jacobsson ◽  
Christiana Julia Rissing ◽  
David Y. Son
Keyword(s):  
Electron Transfer ◽  
Absorption Maximum ◽  
Steric Effect ◽  
Amide Group ◽  
Spectral Studies ◽  
Amino Group ◽  
Absorption Properties ◽  
Convenient Synthesis

<div>A new series of substituted anthranilic esters derivatives linked with a 1,3-dithiolane and</div><div>benzyloximino moiety was synthesized using the simple esterfication reaction and products were</div><div>fully characterized. The isolated yields of these compounds range from 59 to 96%. 1,3-</div><div>dithiolane ester and the benzyloxy substituted diamine derivatives are white solids and stable to</div><div>air and moisture. The synthesized compounds can be exhibits UV-vis absorption properties by</div><div>their structures with a amine or amide group, It is observed that absorption maximum is excellent</div><div>for 2,6-disubstituted benzyloxy esters which can be explained by electron transfer or conjugation</div><div>is steric effect in ortho substitution from the amino group and the amide group.</div>

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