Synthesis and photophysical studies of blue phosphorescent Ir(III) complexes with dimethylphenylphospine.

Science.gov (United States)

Ham, Ho-Wan; Jung, Kyung-Yoon; Kim, Young-Sik

2012-02-01

New blue emitting mixed ligand iridium(III) complexes comprising one cyclometalating, two phosphines trans to each other such as Ir{(CF3)2Meppy}(PPhMe3)2(H)(L) [L = CI, NCMe, CN] [(CF3)2Meppy = 2-(3', 5'-bis-trifluoromethylphenyl)-4-methylpyridine] were synthesized and studied to tune the phosphorescence wavelength to the deep blue region and to enhance the luminescence efficiencies. To achieve deep blue emission, the trifluoromethyl group substituted on the phenyl ring and the methyl group substituted on the pyridyl ring increased HOMO-LUMO gap and achieved the hypsochromic shift. To gain insight into the factors responsible for the emission color change and the different luminescence efficiency, we investigate the electron-withdrawing capabilities of ancillary ligands using the DFT and TD-DFT calculations on the ground and excited states of the complexes. From these results, we discuss how the ancillary ligand influences the emission peak as well as the metal to ligand charge transfer (MLCT) transition efficiency. The maximum emission spectra of Ir{(CF3)2Meppy}(PPhMe3)2(H)(Cl), [Ir{(CF3),Meppy)(PPhMe3),(H)(NCMe)]+ and Ir{(CF3)2Meppy}(PPhMe3)2(H)(CN) were in the ranges of 441, 435, 434 nm, respectively.

Relaxation dynamics of the LH2 complex from a photosynthetic purple bacterium Thiorhodospira sibirica studied by the near-IR femtosecond pump-probe method

International Nuclear Information System (INIS)

Razjivin, A P; Pishchal'nikov, R Yu; Kozlovskii, V S; Kompanets, V O; Chekalin, Sergei V; Moskalenko, A A; Makhneva, Z K

2005-01-01

Photoinduced changes in the absorption spectrum of the LH2 (B800-830-850) complex from a Thiorhodospira sibirica (Trs. sibirica) bacterium are studied by the pump-probe method. The complex has the anomalous absorption spectrum exhibiting three bands in the near-IR region at 793, 826.5, and 846.5 nm. At room temperature, the excitation energy transfer from the B800, B830, and B859 bands was detected with the time constants τ 1 ∼0.5 ps, τ 2 ∼2.5 ps, and τ 3 of the order of a few hundreds of picoseconds, respectively. A rapid energy transfer from the B830 band compared to energy transfer from the B850 band (τ 2 ||τ 3 ) suggests that all the three bands belong to the same complex (i.e., that the LH2 complex from Trs. sibirica is homogeneous). A slower energy transfer (by three - five times) from the B830 band of the LH2 complex from Trs. sibirica compared to energy transfer from the B800 band of the LH2 complexes (B800-850 and especially B800-820) from other purple bacteria suggests that the electronic structures of ensembles of bacteriochlorophyll molecules in these complexes are substantially different. (laser applications and other topics in quantum electronics)

Strong ligand field effects of blue phosphorescent Ir(III) complexes with phenylpyrazole and phosphines.

Science.gov (United States)

Park, Se Won; Ham, Ho Wan; Kim, Young Sik

2012-04-01

In the paper, we describe new Ir complexes for achieving efficient blue phosphorescence. New blue-emitting mixed-ligand Ir complexes comprising one cyclometalating, two phosphines trans to each other such as Ir(dppz)(PPh3)2(H)(L) (Ll= Cl, NCMe+, CN), [dppz = 3,5-Diphenylpyrazole] were synthesized and studied to tune the phosphorescence wavelength to the deep blue region and to enhance the luminescence efficiencies. To gain insight into the factors responsible for the emission color change and the variation of luminescence efficiency, we investigate the electron-withdrawing capabilities of ancillary ligands using DFT and TD-DFT calculations on the ground and excited states of the complexes. To achieve deep blue emission and increase the emission efficiency, (1) we substitute the phenyl group on the 3-position of the pyrazole ring that lowers the triplet energy enough that the quenching channel is not thermally accessible and (2) change the ancillary ligands coordinated to iridium atom to phosphine and cyano groups known as very strong field ligands. Their inclusion in the coordination sphere can increase the HOMO-LUMO gap to achieve the hypsochromic shift in emission color and lower the HOMO and LUMO energy level, which causes a large d-orbital energy splitting and avoids the quenching effect to improve the luminescence efficiency. The maximum emission spectra of Ir(dppz)(PPh3)2(H)(CI) and Ir(dppz)(PPh3)2(H)(CN) were in the ranges of 439, 432 nm, respectively.

Observation of the long-lived triplet excited state of perylenebisimide (PBI) in C^N cyclometalated Ir(III) complexes and application in photocatalytic oxidation.

Science.gov (United States)

Sun, Jifu; Zhong, Fangfang; Zhao, Jianzhang

2013-07-14

Perylenebisimide (PBI) was used to prepare C^N cyclometalated Ir(III) complexes that show strong absorption of visible light and it is the first time the long-lived triplet excited state of PBI chromophore was observed in a transition metal complex (τT = 22.3 μs). Previously, the lifetime of the triplet state of PBI in transition metal complexes was usually shorter than 1.0 μs. Long-lived triplet excited states are useful for applications in photocatalysis or other photophysical processes concerning triplet-triplet-energy-transfer. PBI and amino-PBI were used for preparation of cyclometalated Ir(III) complexes (Ir-2 and Ir-3), in which the PBI chromophore was connected to the coordination center via C≡C π-conjugation bond. The new complexes show strong absorption in visible region (ε = 34,200 M(-1) cm(-1) at 541 nm for Ir-2, and ε = 19,000 at 669 nm for Ir-3), compared to the model complex Ir(ppy)(bpy)[PF6] Ir-1 (ε PBI-localized long-lived (3)IL states were populated for Ir-2 and Ir-3 upon photoexcitation. The complexes were used as triplet photosensitizers for (1)O2-mediated photooxidation of 1,5-dihydronaphthalene to produce juglone, an important intermediate for preparation of anti-cancer compounds. (1)O2 quantum yields (Φ(Δ)) up to 91% were observed for the new Ir(III) complexes and the overall photosensitizing ability is much higher than the conventional Ir(III) complex Ir-1, which shows the typical weak visible light absorption in visible region. Our results are useful for preparation of transition metal complexes that show strong absorption of visible light and long-lived triplet excited state and for the application of these complexes in photocatalysis.

MULTIMODE quantum calculations of vibrational energies and IR spectrum of the NO{sup +}(H{sub 2}O) cluster using accurate potential energy and dipole moment surfaces

Energy Technology Data Exchange (ETDEWEB)

Homayoon, Zahra, E-mail: zhomayo@emory.edu [Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322 (United States)

2014-09-28

A new, full (nine)-dimensional potential energy surface and dipole moment surface to describe the NO{sup +}(H{sub 2}O) cluster is reported. The PES is based on fitting of roughly 32 000 CCSD(T)-F12/aug-cc-pVTZ electronic energies. The surface is a linear least-squares fit using a permutationally invariant basis with Morse-type variables. The PES is used in a Diffusion Monte Carlo study of the zero-point energy and wavefunction of the NO{sup +}(H{sub 2}O) and NO{sup +}(D{sub 2}O) complexes. Using the calculated ZPE the dissociation energies of the clusters are reported. Vibrational configuration interaction calculations of NO{sup +}(H{sub 2}O) and NO{sup +}(D{sub 2}O) using the MULTIMODE program are performed. The fundamental, a number of overtone, and combination states of the clusters are reported. The IR spectrum of the NO{sup +}(H{sub 2}O) cluster is calculated using 4, 5, 7, and 8 modes VSCF/CI calculations. The anharmonic, coupled vibrational calculations, and IR spectrum show very good agreement with experiment. Mode coupling of the water “antisymmetric” stretching mode with the low-frequency intermolecular modes results in intensity borrowing.

Limit sets for the discrete spectrum of complex Jacobi matrices

International Nuclear Information System (INIS)

Golinskii, L B; Egorova, I E

2005-01-01

The discrete spectrum of complex Jacobi matrices that are compact perturbations of the discrete Laplacian is studied. The precise stabilization rate (in the sense of order) of the matrix elements ensuring the finiteness of the discrete spectrum is found. An example of a Jacobi matrix with discrete spectrum having a unique limit point is constructed. These results are discrete analogues of Pavlov's well-known results on Schroedinger operators with complex potential on a half-axis.

Quantum-chemical, NMR, FT IR, and ESI MS studies of complexes of colchicine with Zn(II).

Science.gov (United States)

Jankowski, Wojciech; Kurek, Joanna; Barczyński, Piotr; Hoffmann, Marcin

2017-04-01

Colchicine is a tropolone alkaloid from Colchicinum autumnale. It shows antifibrotic, antimitotic, and anti-inflammatory activities, and is used to treat gout and Mediterranean fever. In this work, complexes of colchicine with zinc(II) nitrate were synthesized and investigated using DFT, 1 H and 13 C NMR, FT IR, and ESI MS. The counterpoise-corrected and uncorrected interaction energies of these complexes were calculated. We also calculated their 1 H, 13 C NMR, and IR spectra and compared them with the corresponding experimentally obtained data. According to the ESI MS mass spectra, colchicine forms stable complexes with zinc(II) nitrate that have various stoichiometries: 2:1, 1:1:1, and 2:1:1 with respect to colchichine, Zn(II), and nitrate ion. All of the complexes were investigated using the quantum theory of atoms in molecules (QTAIM). The calculated and the measured spectra showed differences before and after the complexation process. Calculated electron densities and bond critical points indicated the presence of bonds between the ligands and the central cation in the investigated complexes that satisfied the quantum theory of atoms in molecules. Graphical Abstract DFT, NMR, FT IR, ESI MS, QTAIM and puckering studies of complexes of colchicine with Zn(II).

Visualizing Infrared (IR) Spectroscopy with Computer Animation

Science.gov (United States)

Abrams, Charles B.; Fine, Leonard W.

1996-01-01

IR Tutor, an interactive, animated infrared (IR) spectroscopy tutorial has been developed for Macintosh and IBM-compatible computers. Using unique color animation, complicated vibrational modes can be introduced to beginning students. Rules governing the appearance of IR absorption bands become obvious because the vibrational modes can be visualized. Each peak in the IR spectrum is highlighted, and the animation of the corresponding normal mode can be shown. Students can study each spectrum stepwise, or click on any individual peak to see its assignment. Important regions of each spectrum can be expanded and spectra can be overlaid for comparison. An introduction to the theory of IR spectroscopy is included, making the program a complete instructional package. Our own success in using this software for teaching and research in both academic and industrial environments will be described. IR Tutor consists of three sections: (1) The 'Introduction' is a review of basic principles of spectroscopy. (2) 'Theory' begins with the classical model of a simple diatomic molecule and is expanded to include larger molecules by introducing normal modes and group frequencies. (3) 'Interpretation' is the heart of the tutorial. Thirteen IR spectra are analyzed in detail, covering the most important functional groups. This section features color animation of each normal mode, full interactivity, overlay of related spectra, and expansion of important regions. This section can also be used as a reference.

Preparation and Property of Acrylic Acid Rare Earth Complex and Its Hydrosilylation

Institute of Scientific and Technical Information of China (English)

Zhang Ming; Chen Haiyan; Chen Xiaosong; Dai Shaojun; Inoue Shinich; Okamoto Hiroshi

2004-01-01

Acrylic acid rare earth complex was prepared. Its chemical composition was determined by chemical and elemental analysis, and its structure as well as properties was characterized using IR, Fluorescence and UV spectrum, and its solubility was also investigated. Meanwhile a kind of elastic functional polymer with rare earth units in the side chains was produced. It is confirmed by IR spectrum that the Si-H bonds really react with acrylic acid rare earth.

Far IR spectra of Th(IV) halide complexes of some heterocyclic bases

International Nuclear Information System (INIS)

Srivastava, A.K.; Agarwal, R.K.; Srivastava, M.; Kapoor, V.; Srivastava, T.N.

1981-01-01

The synthesis and IR spectra of Th(IV) perchlorato, nitrato and thiocyanato complexes of some heterocyclic bases have been reported. Halogens are common ligands in coordination chemistry forming coordinate bonds with metals readily. Metal halogen (M-X) stretching bands show a strong absorption in the far-IR region. Very little information is available on Th-X stretching frequencies. In the present communication, adducts of Th(IV) halide with certain nitrogen heterocyclic bases such as pyridine, α-picoline, 2-amino pyridine, 2:4-lutidine, 2:6-lutidine, quinoline, 2,2'-bipyridine and 1,10-phenanthroline were synthesised and characterised. Experimental details are given. Results are presented and discussed. (author)

The Complex Resistivity Spectrum Characteristics About Stratabound Sulfide Deposits

Science.gov (United States)

Dong, P.; Sun, B.; Wang, L.; Chen, Z.; Dong, Z.; Wu, Y.

2010-12-01

Complex resistivity method has become the key technique of deep prospecting, and widely applied in stratabound sulfide deposits which often form massive ores. However, the complex resistivity spectrum characteristics of stratabound sulfide deposits remains unknown. Through studying variation problem of two-dimensional polarization medium, deducing the differential equations and calculating formula,we applied Cole-Cole model to deduce the spectrum of complex resistivity based on the model of three-node and four-node finite element method, and programmed homologous procedure. We utilized the Earth Model of Geological Layers which has accurate analytical solution to test rationality and accuracy of our modeling. We applied the layer structure provided by drilling results in Chenmenshan copper mine,which is typical strata-bound sulfide deposits in Jiangxi province,China, and calculated the spectra of complex resistivity, then made comparison between modeled and measured values. We find good corellation between them. Our studies may have imporved the interpretation of complex resistivity data, which help apply complex resistivity methods of propecting on stratabound sulfide deposites.

Band shape of IR-absorption of complex molecules and restricted rotational diffusion

International Nuclear Information System (INIS)

Ivanov, E.N.; Umidulaev, Sh.U.

1989-01-01

The development of the theory of band shape (and Breadth) IR-absorption of complex molecules (regarding the molecules inside motions) is considered. It is supposed that a molecule fragment being responsible for IR-absorption takes part in the restricted rotational diffusion (RRD) with respect to the frame, and the molecule itself in general makes rotational motion (RM). Both kinds of motions are discussed in accordance with the theory of group motions representations. On the basis of correlative functions calculations of dipole moment a simple expression for the IR-absorption band shape have been obtained, which in itself uses to be the super position of two Lorencians with the semibreadths 2D 1 and 2D 1 +ν 2 0 (ν 2 0 +1D R accordingly (here D 1 is the coefficient of RM, D 2 is the coefficient of RRD, ν 2 0 is the well known function of RRD-cone divergence angle) in case of symmetric rotary abrasive disc. Analysis of experimental band shape of IR-absorption on the basis of the expression obtained allows to get information of MR-molecule parameters in general and RRD. It is really possible to determine the RRD-cone divergency angle from experimental weights of Lorencians. In accordance with experimental semibreadths the coefficient of RM D 1 and the coefficient of RRD D 2 are obtained. In conclusion it is noted that D 1 →0 (in the expression for the band shape of IR-absorption obtained), one of the Lorencians turns to the δ-function and finally there is an expression which describes IR-absorption band shape of molecules in polymer-mats. (author)

CISAPS: Complex Informational Spectrum for the Analysis of Protein Sequences

Directory of Open Access Journals (Sweden)

Charalambos Chrysostomou

2015-01-01

Full Text Available Complex informational spectrum analysis for protein sequences (CISAPS and its web-based server are developed and presented. As recent studies show, only the use of the absolute spectrum in the analysis of protein sequences using the informational spectrum analysis is proven to be insufficient. Therefore, CISAPS is developed to consider and provide results in three forms including absolute, real, and imaginary spectrum. Biologically related features to the analysis of influenza A subtypes as presented as a case study in this study can also appear individually either in the real or imaginary spectrum. As the results presented, protein classes can present similarities or differences according to the features extracted from CISAPS web server. These associations are probable to be related with the protein feature that the specific amino acid index represents. In addition, various technical issues such as zero-padding and windowing that may affect the analysis are also addressed. CISAPS uses an expanded list of 611 unique amino acid indices where each one represents a different property to perform the analysis. This web-based server enables researchers with little knowledge of signal processing methods to apply and include complex informational spectrum analysis to their work.

Quantum calculations of the IR spectrum of liquid water using ab initio and model potential and dipole moment surfaces and comparison with experiment

Energy Technology Data Exchange (ETDEWEB)

Liu, Hanchao; Wang, Yimin; Bowman, Joel M. [Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322 (United States)

2015-05-21

The calculation and characterization of the IR spectrum of liquid water have remained a challenge for theory. In this paper, we address this challenge using a combination of ab initio approaches, namely, a quantum treatment of IR spectrum using the ab initio WHBB water potential energy surface and a refined ab initio dipole moment surface. The quantum treatment is based on the embedded local monomer method, in which the three intramolecular modes of each embedded H{sub 2}O monomer are fully coupled and also coupled singly to each of six intermolecular modes. The new dipole moment surface consists of a previous spectroscopically accurate 1-body dipole moment surface and a newly fitted ab initio intrinsic 2-body dipole moment. A detailed analysis of the new dipole moment surface in terms of the coordinate dependence of the effective atomic charges is done along with tests of it for the water dimer and prism hexamer double-harmonic spectra against direct ab initio calculations. The liquid configurations are taken from previous molecular dynamics calculations of Skinner and co-workers, using the TIP4P plus E3B rigid monomer water potential. The IR spectrum of water at 300 K in the range of 0–4000 cm{sup −1} is calculated and compared with experiment, using the ab initio WHBB potential and new ab initio dipole moment, the q-TIP4P/F potential, which has a fixed-charged description of the dipole moment, and the TTM3-F potential and dipole moment surfaces. The newly calculated ab initio spectrum is in very good agreement with experiment throughout the above spectral range, both in band positions and intensities. This contrasts to results with the other potentials and dipole moments, especially the fixed-charge q-TIP4P/F model, which gives unrealistic intensities. The calculated ab initio spectrum is analyzed by examining the contribution of various transitions to each band.

Quantum calculations of the IR spectrum of liquid water using ab initio and model potential and dipole moment surfaces and comparison with experiment

International Nuclear Information System (INIS)

Liu, Hanchao; Wang, Yimin; Bowman, Joel M.

2015-01-01

The calculation and characterization of the IR spectrum of liquid water have remained a challenge for theory. In this paper, we address this challenge using a combination of ab initio approaches, namely, a quantum treatment of IR spectrum using the ab initio WHBB water potential energy surface and a refined ab initio dipole moment surface. The quantum treatment is based on the embedded local monomer method, in which the three intramolecular modes of each embedded H 2 O monomer are fully coupled and also coupled singly to each of six intermolecular modes. The new dipole moment surface consists of a previous spectroscopically accurate 1-body dipole moment surface and a newly fitted ab initio intrinsic 2-body dipole moment. A detailed analysis of the new dipole moment surface in terms of the coordinate dependence of the effective atomic charges is done along with tests of it for the water dimer and prism hexamer double-harmonic spectra against direct ab initio calculations. The liquid configurations are taken from previous molecular dynamics calculations of Skinner and co-workers, using the TIP4P plus E3B rigid monomer water potential. The IR spectrum of water at 300 K in the range of 0–4000 cm −1 is calculated and compared with experiment, using the ab initio WHBB potential and new ab initio dipole moment, the q-TIP4P/F potential, which has a fixed-charged description of the dipole moment, and the TTM3-F potential and dipole moment surfaces. The newly calculated ab initio spectrum is in very good agreement with experiment throughout the above spectral range, both in band positions and intensities. This contrasts to results with the other potentials and dipole moments, especially the fixed-charge q-TIP4P/F model, which gives unrealistic intensities. The calculated ab initio spectrum is analyzed by examining the contribution of various transitions to each band

Theoretical research on effects of substituents and the solvent on quadruple hydrogen bonded complexes

Directory of Open Access Journals (Sweden)

Lingjia Xu

2007-04-01

Full Text Available Semiempirical AM1 and INDO/CIS methods were used to study the structures and spectroscopy of hydrogen bonded complexes formed by the oligophenyleneethynylene (monomer A with isophthalic acid (monomer B. The binding energies of the complexes are lowered by increasing electron-donating abilities of the substituents near the hydrogen bonds on monomer A. The first absorptions in the electronic spectra and the vibration frequencies of the N-H bonds in the IR spectra for the complexes are both red-shifted compared with those of the monomers. The presence of dimethylsulfoxide (DMSO can reduce the binding energy of the complex through hydrogen bonding. This results in a blue-shift for the first absorption in the electronic spectrum and red-shift for the vibration frequencies of the N-H bonds in the IR spectrum of the complex.

Platinum-group elements fractionation by selective complexing, the Os, Ir, Ru, Rh-arsenide-sulfide systems above 1020 °C

Science.gov (United States)

Helmy, Hassan M.; Bragagni, Alessandro

2017-11-01

The platinum-group element (PGE) contents in magmatic ores and rocks are normally in the low μg/g (even in the ng/g) level, yet they form discrete platinum-group mineral (PGM) phases. IPGE (Os, Ir, Ru) + Rh form alloys, sulfides, and sulfarsenides while Pt and Pd form arsenides, tellurides, bismuthoids and antimonides. We experimentally investigate the behavior of Os, Ru, Ir and Rh in As-bearing sulfide system between 1300 and 1020 °C and show that the prominent mineralogical difference between IPGE (+Rh) and Pt and Pd reflects different chemical preference in the sulfide melt. At temperatures above 1200 °C, Os shows a tendency to form alloys. Ruthenium forms a sulfide (laurite RuS2) while Ir and Rh form sulfarsenides (irarsite IrAsS and hollingworthite RhAsS, respectively). The chemical preference of PGE is selective: IPGE + Rh form metal-metal, metal-S and metal-AsS complexes while Pt and Pd form semimetal complexes. Selective complexing followed by mechanical separation of IPGE (and Rh)-ligand from Pt- and Pd-ligand associations lead to PGE fractionation.

How easy is CO2 fixation by M-C bond containing complexes (M = Cu, Ni, Co, Rh, Ir)?

KAUST Repository

Nolan, Steve; Cavallo, Luigi; Poater, Albert; Vummaleti, Sai V. C.; Talarico, Giovanni

2015-01-01

A comparison between different M–C bonds (M = Cu(I), Ni(II), Co(I), Rh(I) and Ir(I)) has been reported by using density functional theory (DFT) calculations to explore the role of the metal in the fixation or incorporation of CO2 into such complexes. The systems investigated are various metal based congeners of the Ir-complex 8 [(cod)(IiPr)Ir-CCPh], with a ligand scaffold based on cod and IiPr ligands (cod = 1,5-cyclooctadiene; IiPr = 1,3-bis(isopropyl)imidazol-2-ylidene). The results of this study show that the calculated CO2 insertion barriers follow the trend: Cu(I) (20.8 kcal mol−1) < Rh(I) (30.0 kcal mol−1) < Co(I) (31.3 kcal mol−1) < Ir(I) (37.5 kcal mol−1) < Ni(II) (45.4 kcal mol−1), indicating that the Cu(I) based analogue is the best CO2 fixer, while Ni(II) is the worst in the studied series.

How easy is CO2 fixation by M-C bond containing complexes (M = Cu, Ni, Co, Rh, Ir)?

KAUST Repository

Nolan, Steve

2015-11-27

A comparison between different M–C bonds (M = Cu(I), Ni(II), Co(I), Rh(I) and Ir(I)) has been reported by using density functional theory (DFT) calculations to explore the role of the metal in the fixation or incorporation of CO2 into such complexes. The systems investigated are various metal based congeners of the Ir-complex 8 [(cod)(IiPr)Ir-CCPh], with a ligand scaffold based on cod and IiPr ligands (cod = 1,5-cyclooctadiene; IiPr = 1,3-bis(isopropyl)imidazol-2-ylidene). The results of this study show that the calculated CO2 insertion barriers follow the trend: Cu(I) (20.8 kcal mol−1) < Rh(I) (30.0 kcal mol−1) < Co(I) (31.3 kcal mol−1) < Ir(I) (37.5 kcal mol−1) < Ni(II) (45.4 kcal mol−1), indicating that the Cu(I) based analogue is the best CO2 fixer, while Ni(II) is the worst in the studied series.

Characterization of a new Tc (V) - glucosazine complex by UV - VIS and IR spectroscopy

International Nuclear Information System (INIS)

Ganzerli Valentini, M.T.; Stella, R.; Maggi, L.

1989-01-01

A new radiopharmaceutical is proposed for brain and heart functional and radiodiagnostic studies. A Tc complex containing the glucose molecule and chelating groups that do not alter the basic chemical features of the molecule has been prepared. The ligand is formed by the combination of one hydrazine molecule with two sugar molecules and is the first product of the D-glucose-hydrazine reaction that in aqueous basic medium may proceed up to hydrazone and in acid medium up to osazone. These transformations are observed at pH>5 through the UV absorption peaks at 274 and 224 nm, and at pH 1 . UV absorption spectra of the complex, dissolved in water as well as in acetonitrile, have been recorded: the characteristic single peak at 274 nm and at 276 nm respectively for the two solvents is unaffected by the presence of free ligand, due to the quasi null absorption in this spectral region. Molar extinction coefficient is found equal to 20850 L.mol 1 .cm 1 in solutions whose Tc concentration was in the range 2x10 5 -5x10 4 M and the ligand 10 2 - 10 1 M. The IR absorption spectrum has a C=N stretching band at 1620 cm 1 which means that the acyclic form of the azine is predominant; other large and strong bands refer to OH stretching at 3300 cm 1 , to C-O stretching at 1020 cm 1 and to C-N stretching (typical of the cyclic form) at 1080 cm 1 . (author)

Synthesis of iridacarborane halide complexes [(η-9-SMe2-7,8-C2B9H10)IrX2]2 (X=Cl, Br, I)

International Nuclear Information System (INIS)

Kudinov, A.R.; Perekalin, D.S.; Petrovskij, P.V.

2001-01-01

By interaction between Na[9-SMe 2 -7,8-C 2 B 9 H 10 ] and [(Cod)IrCl] 2 (Cod - cycloocta-1,5-diene) iridium complex (η-9-SMe 2 -7,8-C 2 B 9 H 10 )Ir(Cod), which under the action of anhydrous hydrohalogenic acids HX (X=Cl, Br, I) yields iridacarborane halide complexes [(η-9-SMe 2 -7,8-C 2 B 9 H 10 )IrX 2 ] 2 , being analogs of cyclopentadienyl complexes [(C 5 Me 5 )IrX 2 ] 2 . The complexes prepared were characterized on the basis of data of elementary analysis and 1 H, 11 B NMR spectra [ru

Olivine Composition of the Mars Trojan 5261 Eureka: Spitzer IRS Data

Science.gov (United States)

Lim, L. F.; Burt, B. J.; Emery, J. P.; Mueller, M.; Rivkin, A. S.; Trilling, D.

2011-01-01

The largest Mars trojan, 5261 Eureka, is one of two prototype "Sa" asteroids in the Bus-Demeo taxonomy. Analysis of its visible/near-IR spectrum led to the conclusion that it might represent either an angritic analog or an olivine-rich composition such as an R chondrite. Spitzer IRS data (5-30 micrometers) have enabled us to resolve this ambiguity. The thermal-IR spectrum exhibits strong olivine reststrahlen features consistent with a composition of approximately equals Fo60-70. Laboratory spectra of R chondrites, brachinites, and chassignites are dominated by similar features.

Synthesis and IR spectroscopic investigation of solvated complexes of dioxomolybdenum (6) with salicylal-S-methyl isothiosemicarbazone

International Nuclear Information System (INIS)

Abramenko, V.L.; Sergienko, V.S.

1996-01-01

The complex of MoO 2 L (H 2 L-S-methylizothiosemicarbazone of salicyl aldehyde) and its seven solvated derivatives MoO 2 LxSolv, have been synthesized, their IR spectroscopic study being conducted. The conclusions on the structure of the complexes studied are confirmed by ata of x-ray diffraction analysis. Refs. 4, tabs. 1

Effect of second-sphere cation nature on the character of IR spectra of molybdeum(4, 5) cyanide complexes

International Nuclear Information System (INIS)

Zubritskaya, D.I.; Semenishin, D.I.; Vretsena, N.B.; Chernyak, B.I.

1989-01-01

The effect of nature of second-sphere cations on IR spectra of molybdeum (4, 5) cyanide complexes is studied. It is found that the increase in the first ionization potential (radius decrease) brings about the increase in the frequency of valent variations ν (CN). This proves the possibility of formation of bridge bonds Mo-CN-M in the compounds (M-alkali, alkaline earth or rare earth metal, Cs, Y). The conclusion is made on a considerable effect of the nature of second-sphere cations and oxidation degree of complexing agent atoms on the nature of IR spectra of octacyanomolybdates (4, 5)

Research on Characteristics, Antioxidant and Antitumor Activities of Dihydroquercetin and Its Complexes

Directory of Open Access Journals (Sweden)

Yan Zhang

2017-12-01

Full Text Available Dihydroquercetin is a kind of dihydroflavonol compounds with antioxidant, antitumor, antivirus and radioresistance activities. This study attempted to produce the dihydroquercetin complexes with lecithin and β-cyclodextrin, and research their characteristics and bioactivities via ultraviolet spectrum (UV, infrared spectroscopy (IR, scanning electron microscope (SEM, differential scanning calorimetry (DSC, X-ray diffraction spectrum (XRD, and MTT assay. Results showed that the complexes with lecithin and β-cyclodextrin could improve the solubility and dissolution rate, and remove the characteristic endothermic peak of dihydroquercetin. IR spectra proved their interaction, and results of SEM and XRD showed the amorphous characteristics of the dihydroquercetin compounds. These results indicated that dihydroquercetin was combined by lecithin or β-cyclodextrin with better physical and chemical properties, which would effectively improve the application value in the food and drug industries.

Calculation of the structure and IR spectrum of methyl-b-D-glucopyranoside by density functional theory

International Nuclear Information System (INIS)

Babkov, L.M.; Korolevich, M.V.; Moisejkina, E.A.

2010-01-01

Structural-dynamic models of methyl-b-D-glucopyranoside have been constructed by a density functional method using a B3LYP functional in bases 6-31G(d) and 6-31+G(d,p). Energies have been minimized. Structures, dipole moments, polarizabilities, frequencies of normal modes in the harmonic approximation, and the intensity distribution in the molecular IR spectrum have been calculated. The calculation results have been compared with both the experimental spectra of methyl-b-D-glucopyranoside in the region 400-3700 cm -1 and data obtained within the framework of an approach that uses the classical valence-force method to calculate normal mode frequencies and the quantum-chemical CNDO/2 technique to calculate the electronic structure. (authors)

FT-IR, RAMAN AND DFT STUDIES ON THE VIBRATIONAL ...

African Journals Online (AJOL)

Department of Physics, Science Faculty, Anadolu University, Eskişehir, Turkey ... IR spectrum was recorded using Bruker Optics IFS66v/s FTIR spectrometer at a ... spectrum was obtained using a Bruker Senterra Dispersive Raman microscope.

Completely automated open-path FT-IR spectrometry.

Science.gov (United States)

Griffiths, Peter R; Shao, Limin; Leytem, April B

2009-01-01

Atmospheric analysis by open-path Fourier-transform infrared (OP/FT-IR) spectrometry has been possible for over two decades but has not been widely used because of the limitations of the software of commercial instruments. In this paper, we describe the current state-of-the-art of the hardware and software that constitutes a contemporary OP/FT-IR spectrometer. We then describe advances that have been made in our laboratory that have enabled many of the limitations of this type of instrument to be overcome. These include not having to acquire a single-beam background spectrum that compensates for absorption features in the spectra of atmospheric water vapor and carbon dioxide. Instead, an easily measured "short path-length" background spectrum is used for calculation of each absorbance spectrum that is measured over a long path-length. To accomplish this goal, the algorithm used to calculate the concentrations of trace atmospheric molecules was changed from classical least-squares regression (CLS) to partial least-squares regression (PLS). For calibration, OP/FT-IR spectra are measured in pristine air over a wide variety of path-lengths, temperatures, and humidities, ratioed against a short-path background, and converted to absorbance; the reference spectrum of each analyte is then multiplied by randomly selected coefficients and added to these background spectra. Automatic baseline correction for small molecules with resolved rotational fine structure, such as ammonia and methane, is effected using wavelet transforms. A novel method of correcting for the effect of the nonlinear response of mercury cadmium telluride detectors is also incorporated. Finally, target factor analysis may be used to detect the onset of a given pollutant when its concentration exceeds a certain threshold. In this way, the concentration of atmospheric species has been obtained from OP/FT-IR spectra measured at intervals of 1 min over a period of many hours with no operator intervention.

detectIR: a novel program for detecting perfect and imperfect inverted repeats using complex numbers and vector calculation.

Science.gov (United States)

Ye, Congting; Ji, Guoli; Li, Lei; Liang, Chun

2014-01-01

Inverted repeats are present in abundance in both prokaryotic and eukaryotic genomes and can form DNA secondary structures--hairpins and cruciforms that are involved in many important biological processes. Bioinformatics tools for efficient and accurate detection of inverted repeats are desirable, because existing tools are often less accurate and time consuming, sometimes incapable of dealing with genome-scale input data. Here, we present a MATLAB-based program called detectIR for the perfect and imperfect inverted repeat detection that utilizes complex numbers and vector calculation and allows genome-scale data inputs. A novel algorithm is adopted in detectIR to convert the conventional sequence string comparison in inverted repeat detection into vector calculation of complex numbers, allowing non-complementary pairs (mismatches) in the pairing stem and a non-palindromic spacer (loop or gaps) in the middle of inverted repeats. Compared with existing popular tools, our program performs with significantly higher accuracy and efficiency. Using genome sequence data from HIV-1, Arabidopsis thaliana, Homo sapiens and Zea mays for comparison, detectIR can find lots of inverted repeats missed by existing tools whose outputs often contain many invalid cases. detectIR is open source and its source code is freely available at: https://sourceforge.net/projects/detectir.

Cationic Protic Imidazolylidene NHC Complexes of Cp*IrCl+ and Cp*RhCl+ with a Pyridyl Tether Formed at Ambient Temperature

Directory of Open Access Journals (Sweden)

Douglas B. Grotjahn

2018-02-01

Full Text Available Protic NHC (PNHC complexes with N1H, N2-alkyl/aryl imidazolylidene ligands are relatively rare, and routes for their synthesis differ from what is used to make non-protic analogs. Prior work from our group and others showed that in the presence of a tethering ligand (phosphine or in one case, pyridine, CpM and Cp*M (M = Ir, Ru PNHC complexes could be made by heating. Here, we find that the use of ionizing agents to activate [Cp*MIIICl(μ-Cl]2 (M = Ir, Rh allows for what we believe is unprecedented ambient temperature formation of PNHC complexes from neutral imidazoles; the product complexes are able to perform transfer hydrogenation.

Electronic Structures of Reduced and Superreduced Ir2(1,8-diisocyanomenthane)4 n+ Complexes

Czech Academy of Sciences Publication Activity Database

Záliš, Stanislav; Hunter, B. M.; Gray, H. B.; Vlček, Antonín

2017-01-01

Roč. 56, č. 5 (2017), s. 2874-2883 ISSN 0020-1669 R&D Projects: GA MŠk LD14129 Grant - others:COST(XE) CM1405; COST(XE) CM1202 Institutional support: RVO:61388955 Keywords : electronic structure * electrochemistry * Ir2(1,8-diisocyanomenthane)4 n+ Complexes Subject RIV: CG - Electrochemistry OBOR OECD: Physical chemistry Impact factor: 4.857, year: 2016

Single-nucleotide polymorphism of INS, INSR, IRS1, IRS2, PPAR-G ...

Indian Academy of Sciences (India)

2017-03-02

Mar 2, 2017 ... Abstract. Polycystic ovary syndrome (PCOS) is the most common and a complex female endocrine disorder, and is one of the leading cause of female infertility. Here, we aimed to investigate the association of single-nucleotide polymorphism of INS, INSR,. IRS1, IRS2, PPAR-G and CAPN10 gene in the ...

Kas netilpo tarp politikos ir diplomatijos?

OpenAIRE

Streikus, Arūnas

2008-01-01

The review analyzes A. Kasparavičius’s monograph “Tarp Politikos ir Diplomatijos: Šventasis Sostas ir Lietuvos Respublika” (Vilnius, 2008). The historiographic value of the study is undisputed. A. Kasperavičius had an opportunity to use a broad spectrum of sources, among which two sets of archive documents stand out: the funds of the archives of Ministry of Foreign Affairs of Lithuania and the Lithuanian Embassy under the Holy See in Rome. A. Kasparavičius managed to avoid the arid scientific...

High field Moessbauer study of dilute Ir-(Fe) alloys

International Nuclear Information System (INIS)

Takabatake, Toshiro; Mazaki, Hiromasa; Shinjo, Teruya.

1981-01-01

The magnetic behavior of very dilute Fe impurities in Ir has been studied by means of Moessbauer measurement in external fields up to 80 kOe at 4.2 K. The saturation hyperfine field increases in proportion to the external field up to the maximum magnetic field available. This means that for a localized spin fluctuation system IrFe, the effective magnetic moment associated with Fe impurities is induced in proportion to the external field. No anomalous spectrum was observed with a very dilute sample (--10 ppm 57 Co), indicating that the interaction between impurities is responsible for the anomalous spectrum previously observed with a less homogeneous sample. (author)

High-dimensional fitting of sparse datasets of CCSD(T) electronic energies and MP2 dipole moments, illustrated for the formic acid dimer and its complex IR spectrum

Science.gov (United States)

Qu, Chen; Bowman, Joel M.

2018-06-01

We present high-level, coupled-mode calculations of the infrared spectrum of the cyclic formic acid dimer. The calculations make use of full-dimensional, ab initio potential energy and dipole moment surfaces. The potential is a linear least-squares fit to 13 475 CCSD(T)-F12a/haTZ (haTZ means aug-cc-pVTZ basis set for O and C, and cc-pVTZ for H) energies, and the dipole moment surface is a fit to the dipole components, calculated at the MP2/haTZ level of theory. The variables of both fits are all (45) internuclear distances (actually Morse variables). The potential, which is fully permutationally invariant, is the one published recently and the dipole moment surface is newly reported here. Details of the fits, especially the dipole moment, and the database of configurations are given. The infrared spectrum of the dimer is calculated by solving the nuclear Schrödinger equation using a vibrational self-consistent field and virtual-state configuration interaction method, with subsets of the 24 normal modes, up to 15 modes. The calculations indicate strong mode-coupling in the C—H and O—H stretching region of the spectrum. Comparisons are made with experiments and the complexity of the experimental spectrum in the C—H and O—H stretching region is successfully reproduced.

Infrared Spectroscopy of Gas-Phase M+(CO2)n (M = Co, Rh, Ir) Ion-Molecule Complexes.

Science.gov (United States)

Iskra, Andreas; Gentleman, Alexander S; Kartouzian, Aras; Kent, Michael J; Sharp, Alastair P; Mackenzie, Stuart R

2017-01-12

The structures of gas-phase M + (CO 2 ) n (M = Co, Rh, Ir; n = 2-15) ion-molecule complexes have been investigated using a combination of infrared resonance-enhanced photodissociation (IR-REPD) spectroscopy and density functional theory. The results provide insight into fundamental metal ion-CO 2 interactions, highlighting the trends with increasing ligand number and with different group 9 ions. Spectra have been recorded in the region of the CO 2 asymmetric stretch around 2350 cm -1 using the inert messenger technique and their interpretation has been aided by comparison with simulated infrared spectra of calculated low-energy isomeric structures. All vibrational bands in the smaller complexes are blue-shifted relative to the asymmetric stretch in free CO 2 , consistent with direct binding to the metal center dominated by charge-quadrupole interactions. For all three metal ions, a core [M + (CO 2 ) 2 ] structure is identified to which subsequent ligands are less strongly bound. No evidence is observed in this size regime for complete activation or insertion reactions.

VizieR Online Data Catalog: IRS spectra with features of crystalline silicates (Chen+, 2016)

Science.gov (United States)

Chen, R.; Luo, A.; Liu, J.; Jiang, B.

2018-04-01

Spectra taken by the IRS (Houck et al. 2004ApJS..154...18H) on the Spitzer space telescope (Werner et al. 2004ApJS..154....1W) are now publicly available. These spectra are produced using the bksub.tbl products from SL and LL modules of final SSC pipeline, version 18.18. From the IRS data archive, we found a collection of 16986 low-resolution spectra. The spectra are merged by four slits: SL2 (5.21-7.56 μm), SL1 (7.57-14.28 μm), LL2 (14.29-20.66 μm), and LL1 (20.67-38.00 μm). As crystalline silicates have no features in the SL2 band, we choose the spectra that include all the other three bands: SL1, LL2, and LL1 so that the object has a continuous spectrum from about 7.5-38 μm. In this way, five of the seven infrared complexes of crystalline silicates are covered, i.e., the 10, 18, 23, 28, and 33 μm complexes. (5 data files).

Variable Denticity in Carboxylate Binding to the Uranyl Coordination Complexes

International Nuclear Information System (INIS)

Groenewold, G.S.; De Jong, Wibe A.; Oomens, Jos; Van Stipdonk, Michael J.

2010-01-01

Tris-carboxylate complexes of the uranyl (UO2)2+ cation with acetate and benzoate were generated using electrospray ionization mass spectrometry, and then isolated in a Fourier transformion cyclotron resonance mass spectrometer. Wavelength-selective infrared multiple photon dissociation (IRMPD) of the tris-acetatouranyl anion resulted in a redox elimination of an acetate radical, which was used to generate an IR spectrum that consisted of six prominent absorption bands. These were interpreted with the aid of density functional theory calculations in terms of symmetric and antisymmetric -CO2 stretches of both the monodentate and bidentate acetate, CH3 bending and umbrella vibrations, and a uranyl O-U-O asymmetric stretch. The comparison of the calculated and measured IR spectra indicated that the tris-acetate complex contained two acetate ligands bound in a bidentate fashion, while the third acetate was monodentate. In similar fashion, the tris-benzoate uranyl anion was formed and photodissociated by loss of a benzoate radical, enabling measurement of the infrared spectrum that was in close agreement with that calculated for a structure containing one monodentate, and two bidentate benzoate ligands.

Theoretical characterization of quaternary iridium based hydrides NaAeIrH{sub 6} (Ae = Ca, Ba and Sr)

Energy Technology Data Exchange (ETDEWEB)

Bouras, S. [Laboratory of Studies Surfaces and Interfaces of Solids Materials, Department of Physics, Faculty of Science, University of Setif 1, 19000 (Algeria); Ghebouli, B., E-mail: bghebouli@yahoo.fr [Laboratory of Studies Surfaces and Interfaces of Solids Materials, Department of Physics, Faculty of Science, University of Setif 1, 19000 (Algeria); Benkerri, M. [Laboratory of Studies Surfaces and Interfaces of Solids Materials, Department of Physics, Faculty of Science, University of Setif 1, 19000 (Algeria); Ghebouli, M.A., E-mail: med.amineghebouli@yahoo.fr [Microelectronic Laboratory (LMSE), University of Bachir Ibrahimi, Bordj-Bou-Arreridj 34000 (Algeria); Research Unit on Emerging Materials (RUEM), University of Setif 1, 19000 (Algeria); Choutri, H. [Microelectronic Laboratory (LMSE), University of Bachir Ibrahimi, Bordj-Bou-Arreridj 34000 (Algeria); Louail, L.; Chihi, T.; Fatmi, M. [Research Unit on Emerging Materials (RUEM), University of Setif 1, 19000 (Algeria); Bouhemadou, A. [Laboratory for Developing New Materials and Their Characterization, Department of Physics, Faculty of Science, University of Setif 1, 19000 (Algeria); Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Khenata, R.; Khachai, H. [Laboratoire de Physique Quantique et de Modélisation Mathématique, Université de Mascara, 29000 (Algeria)

2015-01-15

The quaternary iridium based hydrides NaAeIrH{sub 6} (Ae = Ca, Ba and Sr) are promising candidates as hydrogen storage materials. We have studied the structural, elastic, electronic, optical and thermodynamic properties of NaAeIrH{sub 6} (Ae = Ca, Ba and Sr) within the generalized gradient approximation, the local density approximation (LDA) and mBj in the frame of density functional perturbation theory. These alloys have a large indirect Γ–X band gap. The thermodynamic functions were computed using the phonon density of states. The origin of the possible transitions from valence band to conduction band was illustrated. By using the complex dielectric function, the optical properties such as absorption, reflectivity, loss function, refractive index and optical conductivity have been obtained. - Graphical abstract: Real and imaginary parts of the dielectric function, the absorption spectrum α(ω), reflectivity R(ω) and energy-loss spectrum L(ω). - Highlights: • NaAeIrH{sub 6} (Ae = Ca, Ba and Sr) alloys have been investigated. • The elastic moduli, energy gaps are predicted. • The optical and thermal properties were studied.

First-principles calculation of monitoring spin states of small magnetic nanostructures with IR spectrum of CO

International Nuclear Information System (INIS)

Li, C; Lefkidis, G; Huebner, W

2010-01-01

A fully ab initio controlled ultrafast magnetooptical switching mechanism in small magnetic clusters is achieved through exploiting spin-orbit-coupling enabled Λ processes. The idea is that in the magnetic molecules a fast transition between two almost degenerate states with different spins can be triggered by a laser pulse, which leads to an electron excitation from one of the degenerate states to a highly spin-mixed state and a deexcitation to the state of opposite spin. In this paper a CO molecule is attached to one magnetic center of the clusters, which serves as an experimental marker to map the laser-induced spin manipulation to the IR spectrum of CO. The predicted spin-state-dependent CO frequencies can facilitate experimental monitoring of the processes. We show that spin flip in magnetic atoms can be achieved in structurally optimized magnetic clusters in a subpicosecond regime with linearly polarized light.

A novel aggregation induced emission active cyclometalated Ir(III) complex as a luminescent probe for detection of copper(II) ion in aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Shen, Wei; Yan, Liqiang; Tian, Wenwen; Cui, Xia; Qi, Zhengjian, E-mail: qizhengjian@seu.edu.cn; Sun, Yueming, E-mail: sun@seu.edu.cn

2016-09-15

We report the synthesis and characterization of a novel aggregation induced emission (AIE) active cyclometalated Ir(III) complex, namely [Ir(dfppy){sub 2}(phen-DPA)]PF{sub 6}, where dfppy and phen-DPA represent 2-(2,4-difluorophenyl)pyridine and 2-(bis(pyridin-2-ylmethyl)amino)-N-(1,10-phenanthrolin-5-yl)acetamide, respectively. The complex showed remarkable selectivity for copper(II) in aqueous solution over other competitive ions. Furthermore, this sensor showed a rapid and reversible response to copper(II) in aqueous solution with a detection limit of 65 nM.

Synthesis, characterization and fluorescence studies of a novel europium complex based sensor

International Nuclear Information System (INIS)

Li Bin; Chen Qiuyun; Wang Yachen; Huang Jing; Li Yang

2010-01-01

A novel europium(III) complex was synthesized using TTA (α-thenoyltrifluoroacetone) as the first ligand and H 2 bpdc (2,2'-bipyridine-3,3'-dicarboxylate) as the second ligand. Elemental analysis, thermal analysis, IR and UV-vis spectrum and fluorescence spectrum of the europium(III) complex were carried out. A characteristic Eu 3+ fluorescence emission was observed in ethanol-water (1:1) solution, indicating that the complex is stable in solution and the emission of Eu(III) ions was not influenced by the water molecules. The fluorescence emission of the complex was quenched completely by the Co 2+ and Fe 3+ ions, but the quenched emission was recovered in the presence of glycine. Moreover, the Eu 3+ emission was very sensitive to pH, so the complex can be used as pH-dependent fluorescence probe or chemosensors.

Optimized Binomial Quantum States of Complex Oscillators with Real Spectrum

International Nuclear Information System (INIS)

Zelaya, K D; Rosas-Ortiz, O

2016-01-01

Classical and nonclassical states of quantum complex oscillators with real spectrum are presented. Such states are bi-orthonormal superpositions of n +1 energy eigenvectors of the system with binomial-like coefficients. For large values of n these optimized binomial states behave as photon added coherent states when the imaginary part of the potential is cancelled. (paper)

Catalytic mechanisms of direct pyrrole synthesis via dehydrogenative coupling mediated by PNP-Ir or PNN-Ru pincer complexes: Crucial role of proton-transfer shuttles in the PNP-Ir system

KAUST Repository

Qu, Shuanglin

2014-04-02

Kempe et al. and Milstein et al. have recently advanced the dehydrogenative coupling methodology to synthesize pyrroles from secondary alcohols (e.g., 3) and β-amino alcohols (e.g., 4), using PNP-Ir (1) and PNN-Ru (2) pincer complexes, respectively. We herein present a DFT study to characterize the catalytic mechanism of these reactions. After precatalyst activation to give active 1A/2A, the transformation proceeds via four stages: 1A/2A-catalyzed alcohol (3) dehydrogenation to give ketone (11), base-facilitated C-N coupling of 11 and 4 to form an imine-alcohol intermediate (18), base-promoted cyclization of 18, and catalyst regeneration via H2 release from 1R/2R. For alcohol dehydrogenations, the bifunctional double hydrogen-transfer pathway is more favorable than that via β-hydride elimination. Generally, proton-transfer (H-transfer) shuttles facilitate various H-transfer processes in both systems. Notwithstanding, H-transfer shuttles play a much more crucial role in the PNP-Ir system than in the PNN-Ru system. Without H-transfer shuttles, the key barriers up to 45.9 kcal/mol in PNP-Ir system are too high to be accessible, while the corresponding barriers (<32.0 kcal/mol) in PNN-Ru system are not unreachable. Another significant difference between the two systems is that the addition of alcohol to 1A giving an alkoxo complex is endergonic by 8.1 kcal/mol, whereas the addition to 2A is exergonic by 8.9 kcal/mol. The thermodynamic difference could be the main reason for PNP-Ir system requiring lower catalyst loading than the PNN-Ru system. We discuss how the differences are resulted in terms of electronic and geometric structures of the catalysts and how to use the features in catalyst development. © 2014 American Chemical Society.

Investigation of anticancer properties of caffeinated complexes via computational chemistry methods

Science.gov (United States)

Sayin, Koray; Üngördü, Ayhan

2018-03-01

Computational investigations were performed for 1,3,7-trimethylpurine-2,6-dione, 3,7-dimethylpurine-2,6-dione, their Ru(II) and Os(III) complexes. B3LYP/6-311 ++G(d,p)(LANL2DZ) level was used in numerical calculations. Geometric parameters, IR spectrum, 1H-, 13C and 15N NMR spectrum were examined in detail. Additionally, contour diagram of frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP) maps, MEP contour and some quantum chemical descriptors were used in the determination of reactivity rankings and active sites. The electron density on the surface was similar to each other in studied complexes. Quantum chemical descriptors were investigated and the anticancer activity of complexes were more than cisplatin and their ligands. Additionally, molecular docking calculations were performed in water between related complexes and a protein (ID: 3WZE). The most interact complex was found as Os complex. The interaction energy was calculated as 342.9 kJ/mol.

Cationic polyhydrido cluster complexes. Crystal and molecular structures of (Ir3(Ph2P(CH2)3PPh2)3(H)7(CO))2+ and (Ir3(Ph2P(CH2)2(2-py))3(H)7)2+

International Nuclear Information System (INIS)

Hsienhau Wang; Casalnuovo, A.L.; Johnson, B.J.; Mueting, A.M.; Pignolet, L.H.

1988-01-01

Two new cationic polyhydrido cluster complexes of iridium have been synthesized and characterized by single-crystal x-ray diffraction and by ir and 1 H and 31 P NMR spectroscopy (Ir 3 (dppp) 3 (H) 7 (CO)) 2+ (2) and (Ir3 (PN) 3 (H) 7)2+ (5), where dppp = 1,3-bis(diphenylphosphino)propane and PN = 1-(2-pyridyl)-2-(diphenylphosphino)ethane, were synthesized by the reaction of CO with (Ir 3 (dppp) 3 (H) 7 ) 2+ (1) in CH 2 Cl 2 solution and H 2 with (Ir(PN)(COD)) + (4) in CH 3 OH solution, respectively. Crystal structures for both compounds is reported. The hydride positions were not located in the crystal structure analyses but were deduced from structural and 1 H NMR data. The molecular structure of 2 consists of a bilateral triangle of three iridium atoms with a carbonyl at the vertex and a chelating dppp ligand on each iridium atom. 1 H NMR data with use of acetone-d 6 as solvent showed that 2 possesses four doubly bridging hydrides and three terminal hydrides, yielding C 1 symmetry. The molecular structure of 5 consists of an approximately equilateral triangle of three iridium atoms (average Ir-Ir distance 2.746 (1) angstrom) with one PN ligand chelated to each iridium atom. 1 H NMR analysis, with use of CD 2 Cl 2 as solvent, showed that 5 has one triply bridging hydride and six terminal hydrides, giving C 3 symmetry. (Ir 3 (dppp) 3 (H) 7 (CH 3 C 6 H 4 NC)) 2+ (3) a complex structurally analogous to 2, was synthesized from 1 and p-tolyl isocyanide in CH 2 Cl 2 solution and characterized by ir and 1 H and 31 P NMR spectroscopy. 44 refs., 3 figs., 3 tabs

CF3CH(ONO)CF3: Synthesis, IR spectrum, and use as OH radical source for kinetic and mechanistic studies

DEFF Research Database (Denmark)

Andersen, Mads Peter Sulbæk; Hurley, MD; Ball, JC

2003-01-01

The synthesis, IR spectrum, and first-principles characterization of CF3CH(ONO)CF3 as well as its use as an OH radical source in kinetic and mechanistic studies are reported. CF3CH(ONO)CF3 exists in two conformers corresponding to rotation about the RCO-NO bond. The more prevalent trans conformer......C(O)CF3 and, by implication, OH radicals in 100% yield. CF3CH(ONO)CF3 photolysis is a convenient source of OH radicals in the studies of the yields of CO, CO2, HCHO, and HC(O)OH products which can be difficult to measure using more conventional OH radical sources (e.g., CH3ONO photolysis). CF3CH...

Distinct signalling properties of insulin receptor substrate (IRS)-1 and IRS-2 in mediating insulin/IGF-1 action

DEFF Research Database (Denmark)

Rabiee, Atefeh; Krüger, Marcus; Ardenkjær-Larsen, Jacob

2018-01-01

Insulin/IGF-1 action is driven by a complex and highly integrated signalling network. Loss-of-function studies indicate that the major insulin/IGF-1 receptor substrate (IRS) proteins, IRS-1 and IRS-2, mediate different biological functions in vitro and in vivo, suggesting specific signalling...... properties despite their high degree of homology. To identify mechanisms contributing to the differential signalling properties of IRS-1 and IRS-2 in the mediation of insulin/IGF-1 action, we performed comprehensive mass spectrometry (MS)-based phosphoproteomic profiling of brown preadipocytes from wild type......, IRS-1-/-and IRS-2-/-mice in the basal and IGF-1-stimulated states. We applied stable isotope labeling by amino acids in cell culture (SILAC) for the accurate quantitation of changes in protein phosphorylation. We found ~10% of the 6262 unique phosphorylation sites detected to be regulated by IGF-1...

On formation mechanism of Pd-Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH3)4][IrCl6

Science.gov (United States)

Asanova, Tatyana I.; Asanov, Igor P.; Kim, Min-Gyu; Gerasimov, Evgeny Yu.; Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V.

2013-10-01

The formation mechanism of Pd-Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH3)4][IrCl6] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 °C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd-Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10-200 nm) and dendrite Ir-rich (10-50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd-Ir nanoparticles, were found to occur.

On formation mechanism of Pd–Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH3)4][IrCl6

International Nuclear Information System (INIS)

Asanova, Tatyana I.; Asanov, Igor P.; Kim, Min-Gyu; Gerasimov, Evgeny Yu.; Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V.

2013-01-01

The formation mechanism of Pd–Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH 3 ) 4 ][IrCl 6 ] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 °C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd–Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10–200 nm) and dendrite Ir-rich (10–50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd–Ir nanoparticles, were found to occur.Graphical Abstract

Microwave Spectrum and Structure of the Methane-Propane Complex

Science.gov (United States)

Peterson, Karen I.; Lin, Wei; Arsenault, Eric A.; Choi, Yoon Jeong; Novick, Stewart E.

2017-06-01

Methane is exceptional in its solid-phase orientational disorder that persists down to 24 K. Only below that temperature does the structure become partially ordered, and full crystallinity requires even lower temperatures and high pressures. Not surprisingly, methane appears to freely rotate in most van der Waals complexes, although two notable exceptions are CH_4-HF and CH_4-C_5H_5N. Of interest to us is how alkane interactions affect the methane rotation. Except for CH_4-CH_4, rotationally-resolved spectra of alkane-alkane complexes have not been studied. To fill this void, we present the microwave spectrum of CH_4-C_3H_8 which is the smallest alkane complex with a practical dipole moment. The microwave spectrum of CH_4-C_3H_8 was measured using the Fourier Transform microwave spectrometer at Wesleyan University. In the region between 7100 and 25300 MHz, we observed approximately 70 transitions that could plausibly be attributed to the CH_4-C_3H_8 complex (requiring high power and the proper mixture of gases). Of these, 16 were assigned to the A-state (lowest internal rotor state of methane) and four to the F-state. The A-state transitions were fitted with a Watson Hamiltonian using nine spectroscopic constants of which A = 7553.8144(97) MHz, B = 2483.9183(35) MHz, and C = 2041.8630(21) MHz. The A rotational constant is only 1.5 MHz higher than that of Ar-C_3H_8 and, since the a-axis of the complex passes approximately through the centers of mass of the subunits, this indicates a similar relative orientation. Thus, we find that the CH_4 is located above the plane of the propane. The center-of-mass separation of the subunits in CH_4-C_3H_8 is calculated to be 3.993 Å, 0.16 Å longer than the Ar-C_3H_8 distance of 3.825 Å, a reasonable difference considering the larger van der Waals radius of CH_4. The four F-state lines, which were about twice as strong as the A-state lines, could be fitted to A, B, and C rotational constants, and further analysis is in progress.

Play complexity and toy engagement in preschoolers with autism spectrum disorder: Do girls and boys differ?

Science.gov (United States)

Harrop, Clare; Green, Jonathan; Hudry, Kristelle

2017-01-01

While sex differences in play have been extensively observed in typical development, only a handful of studies have explored this phenomenon in depth with children with autism spectrum disorders. This study explored sex differences in play complexity and toy engagement within caregiver-child interaction samples for preschool-aged children (2-5 years 11 months) with an autism spectrum disorder who were matched to typically developing children on sex and non-verbal development. Overall we found that girls and boys with autism spectrum disorder were largely equivalent in their play complexity. Despite similar play, girls and boys with autism spectrum disorder differed in a number of ways in their toy engagement, replicating traditional gender differences-girls played more with dolls and domestic items (though at lower rates than typically developing girls) and boys played more with the garage and cars (though at lower rates than typically developing boys). Our findings support the importance and utility of examining sex differences in autism spectrum disorder in light of those observed within typical development. © The Author(s) 2016.

The infrared spectrum of asteroid 433 Eros

Science.gov (United States)

Larson, H. P.; Fink, U.; Treffers, R. R.; Gautier, T. N., III

1976-01-01

The mineralogical composition of asteroid Eros has been determined from its infrared spectrum (0.9-2.7 micrometers; 28/cm resolution). Major minerals include metallic Ni-Fe and pyroxene; no spectroscopic evidence for olivine or plagioclase feldspar was found. The IR spectrum of Eros is most consistent with a stony-iron composition.

Prediction of the oversulphated chondroitin sulphate contamination of unfractionated heparin by ATR-IR spectrophotometry.

Science.gov (United States)

Norwig, J; Beyer, T; Brinz, D; Holzgrabe, U; Diller, M; Manns, D

2009-03-01

The detection of a contamination of heparin with oversulphated chondroitin sulphate (OSCS) was first analysed in an unfractionated heparin batch supplied to the US API-market in April 2006. OSCS is a semi-synthetic derivative of the natural occuring glycosaminoglycan chondroitin sulphate. Moreover some spectroscopic characteristics of the substance overlap with those of heparin, so that the infrared (IR) spectra are visually difficult to distinguish whereas (1)H-NMR (Nuclear Magnetic Resonance) spectroscopy or capillary electrophoresis (CE) provides identification by a simple visual inspection of either the spectrum or the electropherogram respectively. However, applying special tools of Multivariate Data Analysis (MVA) to the IR spectra an identification of the contaminated samples is possible. In detail a rapid Attenuation Total Reflectance-Infrared (ATR-IR) measurement was selected, which does not require any sample preparation. The result (contaminated or not contaminated) is predicted within a few minutes. A method transfer to mobile ATR-IR spectrometers seems to be possible. The analysis is based on the fact that the fingerprint of the OSCS IR spectrum (1st derivative) complies with a theoretically calculated principal component in the MVA.

Highly efficient red phosphorescent Ir(III) complexes for organic light- emitting diodes based on aryl(6-arylpyridin-3-yl)methanone ligands

Energy Technology Data Exchange (ETDEWEB)

Kang, Hyun Ju; Lee, Kum Hee [Department of Chemistry, Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of); Lee, Seok Jae; Seo, Ji Hyun [Department of Information Display, Hongik University, Seoul 121-791 (Korea, Republic of); Kim, Young Kwan, E-mail: kimyk@wow.hongik.ac.kr [Department of Information Display, Hongik University, Seoul 121-791 (Korea, Republic of); Yoon, Seung Soo, E-mail: ssyoon@skku.edu [Department of Chemistry, Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of)

2011-07-29

A series of phosphorescent Ir(III) complexes 1-4 were synthesized based on aryl(6-arylpyridin-3-yl)methanone ligands, and their photophysical and electroluminescent properties were characterized. Multilayer devices with the configuration, Indium tin oxide/4,4',4''-tris(N-(naphthalene-2-yl)-N-phenyl-amino)triphenylamine (60 nm)/4,4'-bis(N-(1-naphthyl)-N-phenylamino)biphenyl (20 nm)/Ir(III) complexes doped in N,N'-dicarbazolyl-4,4'-biphenyl (30 nm, 8%)/2,9-dimethyl-4,7-diphenyl-phenathroline (10 nm)/tris(8-hydroxyquinoline)-aluminum (20 nm)/lithium quinolate (2 nm)/ Al (100 nm), were fabricated. Among these, the device employing complex 2 as a dopant exhibited efficient red emission with a maximum luminance, luminous efficiency, power efficiency and quantum efficiency of 16200 cd/m{sup 2} at 14.0 V, 12.20 cd/A at 20 mA/cm{sup 2}, 4.26 lm/W and 9.26% at 20 mA/cm{sup 2}, respectively, with Commission Internationale de l'Enclairage coordinates of (0.63, 0.37) at 12.0 V.

Selective C--C coupling of ir-ethene and ir-carbenoid radicals

NARCIS (Netherlands)

Dzik, W.I.; Reek, J.N.H.; de Bruin, B.

2008-01-01

The reactivity of the paramagnetic iridium(II) complex [IrII(ethene)(Me3tpa)]2+ (1) (Me3tpa=N,N,N-tris(6-methyl-2-pyridylmethyl) amine) towards the diazo compounds ethyl diazoacetate (EDA) and trimethylsilyldiazomethane (TMSDM) was investigated. The reaction with EDA gave rise to selective CC bond

What Difference Does It Make? Implicit, Explicit and Complex Social Cognition in Autism Spectrum Disorders

Science.gov (United States)

Schaller, Ulrich M.; Rauh, Reinhold

2017-01-01

We tested social cognition abilities of adolescents with autism spectrum disorders (ASD) and neurotypically developed peers (NTD). A multi-faceted test-battery including facial emotion categorization (FEC), classical false belief tasks (FBT), and complex social cognition (SC), yielded significantly lower accuracy rates for FEC and complex SC tasks…

Synthesis and oxidation of CpIrIII compounds: functionalization of a Cp methyl group.

Science.gov (United States)

Park-Gehrke, Lisa S; Freudenthal, John; Kaminsky, Werner; Dipasquale, Antonio G; Mayer, James M

2009-03-21

[CpIrCl(2)](2) () and new CpIr(III)(L-L)X complexes (L-L = N-O or C-N chelating ligands; X = Cl, I, Me) have been prepared and their reactivity with two-electron chemical oxidants explored. Reaction of with PhI(OAc)(2) in wet solvents yields a new chloro-bridged dimer in which each of the Cp ligands has been singly acetoxylated to form [Cp(OAc)Ir(III)Cl(2)](2) () (Cp(OAc) = eta(5)-C(5)Me(4)CH(2)OAc). Complex and related carboxy- and alkoxy-functionalized Cp(OR) complexes can also be prepared from plus (PhIO)(n) and ROH. [Cp(OAc)Ir(III)Cl(2)](2) () and the methoxy analogue [Cp(OMe)Ir(III)Cl(2)](2) () have been structurally characterized. Treatment of [CpIrCl(2)](2) () with 2-phenylpyridine yields CpIr(III)(ppy)Cl () (ppy = cyclometallated 2-phenylpyridyl) which is readily converted to its iodide and methyl analogues CpIr(III)(ppy)I and CpIr(III)(ppy)Me (). CpIr(III) complexes were also prepared with N-O chelating ligands derived from anthranilic acid (2-aminobenzoic acid) and alpha-aminoisobutyric acid (H(2)NCMe(2)COOH), ligands chosen to be relatively oxidation resistant. These complexes and were reacted with potential two-electron oxidants including PhI(OAc)(2), hexachlorocyclohexadienone (C(6)Cl(6)O), N-fluoro-2,4,6-trimethylpyridinium (Me(3)pyF(+)), [Me(3)O]BF(4) and MeOTf (OTf = triflate, CF(3)SO(3)). Iridium(V) complexes were not observed or implicated in these reactions, despite the similarity of the potential products to known CpIr(V) species. The carbon electrophiles [Me(3)O]BF(4) and MeOTf appear to react preferentially at the N-O ligands, to give methyl esters in some cases. Overall, the results indicate that Cp is not inert under oxidizing conditions and is therefore not a good supporting ligand for oxidizing organometallic complexes.

Femtosecond visible/visible and visible/mid-IR pump-probe study of the photosystem II core antenna complex CP47

NARCIS (Netherlands)

Groot, M.L.; Breton, J.; van Wilderen, L.; Dekker, J.P.; van Grondelle, R.

2004-01-01

CP47 is one of the two core antenna proteins of Photosystem II involved in the transfer of solar energy toward the photochemically active reaction center, the D1D2cytb559 complex. We have performed vis/vis and vis/mid-IR pump-probe experiments at room temperature as a first step in linking the

New Ir Bis-Carbonyl Precursor for Water Oxidation Catalysis

Energy Technology Data Exchange (ETDEWEB)

Huang, Daria L. [Department of Chemistry, Yale University, 225; Beltrán-Suito, Rodrigo [Department of Chemistry, Yale University, 225; Thomsen, Julianne M. [Department of Chemistry, Yale University, 225; Hashmi, Sara M. [Department of Chemical and Environmental; Materna, Kelly L. [Department of Chemistry, Yale University, 225; Sheehan, Stafford W. [Catalytic Innovations LLC, 70 Crandall; Mercado, Brandon Q. [Department of Chemistry, Yale University, 225; Brudvig, Gary W. [Department of Chemistry, Yale University, 225; Crabtree, Robert H. [Department of Chemistry, Yale University, 225

2016-02-05

This paper introduces IrI(CO)2(pyalc) (pyalc = (2-pyridyl)-2-propanoate) as an atom-efficient precursor for Ir-based homogeneous oxidation catalysis. This compound was chosen to simplify analysis of the water oxidation catalyst species formed by the previously reported Cp*IrIII(pyalc)OH water oxidation precatalyst. Here, we present a comparative study on the chemical and catalytic properties of these two precursors. Previous studies show that oxidative activation of Cp*Ir-based precursors with NaIO4 results in formation of a blue IrIV species. This activation is concomitant with the loss of the placeholder Cp* ligand which oxidatively degrades to form acetic acid, iodate, and other obligatory byproducts. The activation process requires substantial amounts of primary oxidant, and the degradation products complicate analysis of the resulting IrIV species. The species formed from oxidation of the Ir(CO)2(pyalc) precursor, on the other hand, lacks these degradation products (the CO ligands are easily lost upon oxidation) which allows for more detailed examination of the resulting Ir(pyalc) active species both catalytically and spectroscopically, although complete structural analysis is still elusive. Once Ir(CO)2(pyalc) is activated, the system requires acetic acid or acetate to prevent the formation of nanoparticles. Investigation of the activated bis-carbonyl complex also suggests several Ir(pyalc) isomers may exist in solution. By 1H NMR, activated Ir(CO)2(pyalc) has fewer isomers than activated Cp*Ir complexes, allowing for advanced characterization. Future research in this direction is expected to contribute to a better structural understanding of the active species. A diol crystallization agent was needed for the structure determination of 3.

Synthesis, spectroscopic characterization and antimicrobial activity evaluation of new tridentate Schiff bases and their Co(II complexes

Directory of Open Access Journals (Sweden)

Ganesh More

2017-12-01

Full Text Available A series of Schiff base tridentate ligands and their respective Co(II complexes have been synthesized and characterized by elemental analysis, magnetic susceptibility, IR, NMR and UV–Visible spectra, thermal studies. The IR spectral data suggested that all the ligands acted as monobasic tridentate towards central Co(II ion with an ONO donor atoms sequentially. Analytical data and magnetic susceptibility revealed 1:2 metal to ligand stoichiometry and octahedral geometry for all Co(II complexes. All the prepared compounds were also screened for antimicrobial activity against 5 ESBL (Extended Spectrum β-lactamase and 5 MBL (Metallo β-lactamase producing uropathogens and for antitubercular activity against Mycobacterium tuberculosis (H37Rv strain. Keywords: Schiff base, Antitubercular, Antimicrobial, ESBL, MBL, Metal complex, o-hydroxyl aldehyde, Aminothiophene

Applications of FT-IR spectrophotometry in cancer diagnostics.

Science.gov (United States)

Bunaciu, Andrei A; Hoang, Vu Dang; Aboul-Enein, Hassan Y

2015-01-01

This review provides a brief background to the application of infrared spectroscopy, including Fourier transform-infrared spectroscopy, in biological fluids. It is not meant to be complete or exhaustive but to provide the reader with sufficient background for selected applications in cancer diagnostics. Fourier transform-infrared spectroscopy (FT-IR) is a fast and nondestructive analytical method. The infrared spectrum of a mixture serves as the basis to quantitate its constituents, and a number of common clinical chemistry tests have proven to be feasible using this approach. This review focuses on biomedical FT-IR applications, published in the period 2009-2013, used for early detection of cancer through qualitative and quantitative analysis.

Study on Angelica and its different extracts by Fourier transform infrared spectroscopy and two-dimensional correlation IR spectroscopy

Science.gov (United States)

Liu, Hong-xia; Sun, Su-qin; Lv, Guang-hua; Chan, Kelvin K. C.

2006-05-01

In order to develop a rapid and effective analysis method for studying integrally the main constituents in the medicinal materials and their extracts, discriminating the extracts from different extraction process, comparing the categories of chemical constituents in the different extracts and monitoring the qualities of medicinal materials, we applied Fourier transform infrared spectroscopy (FT-IR) associated with second derivative infrared spectroscopy and two-dimensional correlation infrared spectroscopy (2D-IR) to study the main constituents in traditional Chinese medicine Angelica and its different extracts (extracted by petroleum ether, ethanol and water in turn). The findings indicated that FT-IR spectrum can provide many holistic variation rules of chemical constituents. Use of the macroscopical fingerprint characters of FT-IR and 2D-IR spectrum can not only identify the main chemical constituents in medicinal materials and their different extracts, but also compare the components differences among the similar samples. This analytical method is highly rapid, effective, visual and accurate for pharmaceutical research.

Identification of the fragment of the 1-methylpyrene cation by mid-IR spectroscopy

Science.gov (United States)

Jusko, Pavol; Simon, Aude; Wenzel, Gabi; Brünken, Sandra; Schlemmer, Stephan; Joblin, Christine

2018-04-01

The fragment of the 1-methylpyrene cation, 17C 11H+, is expected to exist in two isomeric forms, 1-pyrenemethylium PyrCH2+ and the tropylium containing species PyrC7+. We measured the infrared (IR) action spectrum of cold 17C 11H+ tagged with Ne using a cryogenic ion trap instrument coupled to the FELIX laser. Comparison of the experimental data with density functional theory calculations allows us to identify the PyrCH2+ isomer in our experiments. The IR Multi-Photon Dissociation spectrum was also recorded following the C2H2 loss channel. Its analysis suggests combined effects of anharmonicity and isomerisation while heating the trapped ions, as shown by molecular dynamics simulations.

Synthesis, Crystal Structure of a Novel Mn Complex with Nicotinoyl-Glycine

Directory of Open Access Journals (Sweden)

Xin Wang

2016-12-01

Full Text Available A novel manganese complex, C16H26MnN4O12, was synthesized by the reaction of nicotinoyl-glycine and NaOH in an ethanol/water solution and structurally characterized by elemental analysis, UV-vis spectrum, IR spectrum and single-crystal X-ray diffraction analysis. The crystal of the complex belongs to the triclinic space group P1 with a = 7.8192(16 Å, b = 8.8800(18 Å, c = 9.0142(18 Å, α = 83.14(3°, β = 65.27(3°, γ = 81.67(3°, V = 516.3(2 Å3, Z = 1, Dx = 1.542 mg·m−3, μ = 0.66 mm−1, F(000 = 271, and final R1 = 0.0381, ωR2 = 0.0964. The nicotinoyl-glycine ligand acts as a bridging ligand to connect the manganese ions by the hydrogen interactions; thus, the complex expands into a 3D supramolecular net structure.

On formation mechanism of Pd-Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH{sub 3}){sub 4}][IrCl{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Asanova, Tatyana I., E-mail: nti@niic.nsc.ru; Asanov, Igor P. [Nikolaev Institute of Inorganic Chemistry SB RAS (Russian Federation); Kim, Min-Gyu [Pohang University of Science and Technology, Beamline Research Division (Korea, Republic of); Gerasimov, Evgeny Yu. [Boreskov Institute of Catalysis SB RAS (Russian Federation); Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V. [Nikolaev Institute of Inorganic Chemistry SB RAS (Russian Federation)

2013-10-15

The formation mechanism of Pd-Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH{sub 3}){sub 4}][IrCl{sub 6}] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 Degree-Sign C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd-Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10-200 nm) and dendrite Ir-rich (10-50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd-Ir nanoparticles, were found to occur.Graphical Abstract.

Study on IR Properties of Reduced Graphene Oxide

Science.gov (United States)

Ma, Deyue; Li, Xiaoxia; Guo, Yuxiang; Zeng, Yurun

2018-01-01

Firstly, the reduced graphene oxide was prepared by modified hummer method and characterized. Then, the complex refractive index of reduced graphene oxide in IR band was tested and its IR absorption and radiation properties were researched by correlated calculation. The results show that reduced graphene oxide prepared by hummer method are multilayered graphene with defects and functional groups on its surface. Its absorption in near and far IR bands is strong, but it’s weaker in middle IR band. At the IR atmosphere Window, its normal spectral emissivity decreases with wavelength increasing, and its total normal spectral emissivity in 3 ∼ 5μm and 8 ∼ 14μm are 0.75 and 0.625, respectively. Therefore, reduced graphene oxide can be used as IR absorption and coating materials and have a great potential in microwave and infrared compatible materials.

Influence of induced colour centres on the frequency - angular spectrum of a light bullet of mid-IR radiation in lithium fluoride

Science.gov (United States)

Chekalin, S. V.; Kompanets, V. O.; Dormidonov, A. E.; Kandidov, V. P.

2017-04-01

The influence of the occurrence of a structure consisting of long-lived colour centres, formed in an LiF crystal upon filamentation of femtosecond mid-IR radiation, on the supercontinuum characteristics is investigated. With an increase in the number of incident pulses, the length and transverse size of the structure of colour centres induced in LiF increase, and the supercontinuum spectrum in the short-wavelength region is markedly transformed due to the occurrence of the waveguide propagation regime, absorption, and scattering of radiation from the newly formed structure of colour centres. Under these conditions, the intensity of the anti-Stokes wing decreases by two orders of magnitude after several tens of pulses. Spectral components arise in the visible range, the angular divergence of which increases with increasing wavelength.

Diogenite-like Features in the Spitzer IRS (5-35 micrometers) Spectrum of 956 ELISA

Science.gov (United States)

Lim, Lucy F.; Emery, Joshua P.; Moskovitz, Nicholas A.

2009-01-01

We report preliminary results from the Spitzer Infrared Spectrograph (IRS) observations of the V-type asteroid 956 Elisa. Elisa was observed as part of a campaign to measure the 5.2-38 micron spectra of small basaltic asteroids with the Spitzer IRS. Targets include members of the dynamical family of the unique large differentiated asteroid 4 Vesta ("Vesroids"), several outer-main-belt basaltic asteroids whose orbits exclude them from originating on 4 Vesta, and the basaltic near-Earth asteroid 4055 Magellan.

Spectroscopic evidence for ternary surface complexes in the lead(II)-malonic acid-hematite system

Science.gov (United States)

Lenhart, J.J.; Bargar, J.R.; Davis, J.A.

2001-01-01

Using extended X-ray absorption fine structure (EXAFS) and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) measurements, we examined the sorption of Pb(II) to hematite in the presence of malonic acid. Pb LIII-edge EXAFS measurements performed in the presence of malonate indicate the presence of both Fe and C neighbors, suggesting that a major fraction of surface-bound malonate is bonded to adsorbed Pb(II). In the absence of Pb(II), ATR-FTIR measurements of sorbed malonate suggest the formation of more than one malonate surface complex. The dissimilarity of the IR spectrum of malonate sorbed on hematite to those for aqueous malonate suggest at least one of the sorbed malonate species is directly coordinated to surface Fe atoms in an inner-sphere mode. In the presence of Pb, little change is seen in the IR spectrum for sorbed malonate, indicating that geometry of malonate as it coordinates to sorbed Pb(II) adions is similar to the geometry of malonate as it coordinates to Fe in the hematite surface. Fits of the raw EXAFS spectra collected from pH 4 to pH 8 result in average Pb-C distances of 2.98 to 3.14 A??, suggesting the presence of both four- and six-membered Pb-malonate rings. The IR results are consistent with this interpretation. Thus, our results suggest that malonate binds to sorbed Pb(II) adions, forming ternary metal-bridging surface complexes. ?? 2001 Academic Press.

IR, Raman and SERS studies of methyl salicylate

Science.gov (United States)

Varghese, Hema Tresa; Yohannan Panicker, C.; Philip, Daizy; Mannekutla, James R.; Inamdar, S. R.

2007-04-01

The IR and Raman spectra of methyl salicylate (MS) were recorded and analysed. Surface enhanced Raman scattering (SERS) spectrum was recorded in silver colloid. The vibrational wave numbers of the compound have been computed using the Hartree-Fock/6-31G * basis and compared with the experimental values. SERS studies suggest a flat orientation of the molecule at the metal surface.

Quantum chemical investigation of levofloxacin-boron complexes: A computational approach

Science.gov (United States)

Sayin, Koray; Karakaş, Duran

2018-04-01

Quantum chemical calculations are performed over some boron complexes with levofloxacin. Boron complex with fluorine atoms are optimized at three different methods (HF, B3LYP and M062X) with 6-31 + G(d) basis set. The best level is determined as M062X/6-31 + G(d) by comparison of experimental and calculated results of complex (1). The other complexes are optimized by using the best level. Structural properties, IR and NMR spectrum are examined in detail. Biological activities of mentioned complexes are investigated by some quantum chemical descriptors and molecular docking analyses. As a result, biological activities of complex (2) and (4) are close to each other and higher than those of other complexes. Additionally, NLO properties of mentioned complexes are investigated by some quantum chemical parameters. It is found that complex (3) is the best candidate for NLO applications.

IR, 1H NMR, mass, XRD and TGA/DTA investigations on the ciprofloxacin/iodine charge-transfer complex.

Science.gov (United States)

Refat, Moamen S; El-Hawary, W F; Moussa, Mohamed A A

2011-05-01

The charge-transfer complex (CTC) of ciprofloxacin drug (CIP) as a donor with iodine (I(2)) as a sigma acceptor has been studied spectrophotometrically in CHCl(3). At maximum absorption bands, the stoichiometry of CIP:iodine system was found to be 1:1 ratio according to molar ratio method. The essential spectroscopic data like formation constant (K(CT)), molar extinction coefficient (ɛ(CT)), standard free energy (ΔG°), oscillator strength (f), transition dipole moment (μ), resonance energy (R(N)) and ionization potential (I(D)) were estimated. The spectroscopic techniques such as IR, (1)H NMR, mass and UV-vis spectra and elemental analyses (CHN) as well as TG-DTG and DTA investigations were used to characterize the chelating behavior of CIP/iodine charge-transfer complex. The iodine CT interaction was associated with a presence of intermolecular hydrogen bond. The X-ray investigation was carried out to investigate the iodine doping in the synthetic CT complex. Copyright © 2011 Elsevier B.V. All rights reserved.

Impaired Insulin Signaling is Associated with Hepatic Mitochondrial Dysfunction in IR+/−-IRS-1+/− Double Heterozygous (IR-IRS1dh Mice

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Andras Franko

2017-05-01

Full Text Available Mitochondria play a pivotal role in energy metabolism, but whether insulin signaling per se could regulate mitochondrial function has not been identified yet. To investigate whether mitochondrial function is regulated by insulin signaling, we analyzed muscle and liver of insulin receptor (IR+/−-insulin receptor substrate-1 (IRS-1+/− double heterozygous (IR-IRS1dh mice, a well described model for insulin resistance. IR-IRS1dh mice were studied at the age of 6 and 12 months and glucose metabolism was determined by glucose and insulin tolerance tests. Mitochondrial enzyme activities, oxygen consumption, and membrane potential were assessed using spectrophotometric, respirometric, and proton motive force analysis, respectively. IR-IRS1dh mice showed elevated serum insulin levels. Hepatic mitochondrial oxygen consumption was reduced in IR-IRS1dh animals at 12 months of age. Furthermore, 6-month-old IR-IRS1dh mice demonstrated enhanced mitochondrial respiration in skeletal muscle, but a tendency of impaired glucose tolerance. On the other hand, 12-month-old IR-IRS1dh mice showed improved glucose tolerance, but normal muscle mitochondrial function. Our data revealed that deficiency in IR/IRS-1 resulted in normal or even elevated skeletal muscle, but impaired hepatic mitochondrial function, suggesting a direct cross-talk between insulin signaling and mitochondria in the liver.

Template synthesis, characterization and antimicrobial activity of the complex combinations of some transitional metals with isonicotinoylhydrazone -2,4,6- trimethylbenzaldehyde

International Nuclear Information System (INIS)

Mitu, L.ITU; Imran, M.

2011-01-01

The complexes of Cu(II), Ni(II), Co(II), Mn(II), and Zn(II) with isonicotinoyl-hydrazone -2,4,6-trimethylbenzaldehyde (INHTB) are reported. The complexes have been characterized by analytical data, IR, UV-Vis, NMR spectra, magnetic susceptibility, thermal analysis and for the Cu(II) complex the ESR spectrum has been recorded. The anti-bacterial activity of these complexes were investigated against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, Shigella flexneri bacteria. The INHTB ligand is coordinated at the metallic ions by oxygen amide (O=C) and the azomethine nitrogen. (author)

Iterative random vs. Kennard-Stone sampling for IR spectrum-based classification task using PLS2-DA

Science.gov (United States)

Lee, Loong Chuen; Liong, Choong-Yeun; Jemain, Abdul Aziz

2018-04-01

External testing (ET) is preferred over auto-prediction (AP) or k-fold-cross-validation in estimating more realistic predictive ability of a statistical model. With IR spectra, Kennard-stone (KS) sampling algorithm is often used to split the data into training and test sets, i.e. respectively for model construction and for model testing. On the other hand, iterative random sampling (IRS) has not been the favored choice though it is theoretically more likely to produce reliable estimation. The aim of this preliminary work is to compare performances of KS and IRS in sampling a representative training set from an attenuated total reflectance - Fourier transform infrared spectral dataset (of four varieties of blue gel pen inks) for PLS2-DA modeling. The `best' performance achievable from the dataset is estimated with AP on the full dataset (APF, error). Both IRS (n = 200) and KS were used to split the dataset in the ratio of 7:3. The classic decision rule (i.e. maximum value-based) is employed for new sample prediction via partial least squares - discriminant analysis (PLS2-DA). Error rate of each model was estimated repeatedly via: (a) AP on full data (APF, error); (b) AP on training set (APS, error); and (c) ET on the respective test set (ETS, error). A good PLS2-DA model is expected to produce APS, error and EVS, error that is similar to the APF, error. Bearing that in mind, the similarities between (a) APS, error vs. APF, error; (b) ETS, error vs. APF, error and; (c) APS, error vs. ETS, error were evaluated using correlation tests (i.e. Pearson and Spearman's rank test), using series of PLS2-DA models computed from KS-set and IRS-set, respectively. Overall, models constructed from IRS-set exhibits more similarities between the internal and external error rates than the respective KS-set, i.e. less risk of overfitting. In conclusion, IRS is more reliable than KS in sampling representative training set.

FT-Raman and FT-IR studies of 1:2.5 piroxicam: β-cyclodextrin inclusion compound

Science.gov (United States)

Bertoluzza, A.; Rossi, M.; Taddei, P.; Redenti, E.; Zanol, M.; Ventura, P.

1999-05-01

The FT-Raman and FT-IR spectra of amorphous 1:2.5 piroxicam (P): β-cyclodextrin (βCD) inclusion compound (PβCD) are presented and discussed in comparison with the spectra of the three main modifications of piroxicam (α,β and monohydrate). In the 1700-1200 cm -1 FT-Raman spectrum of 1:2.5 PβCD inclusion compound the bands of βCD are weak and covered by those stronger of piroxicam, differently from the FT-IR spectrum where the bands of βCD are stronger, so covering a large part of the spectrum. Typical FT-Raman marker bands are assigned for the characterization of the three modifications of piroxicam. The FT-Raman spectrum of 1:2.5 PβCD inclusion compound predominantly shows the bands at about 1465 and 1400 cm -1 of the monohydrate, indicating that piroxicam assumes the zwitterionic structure stabilized by interaction with βCD via electrostatic and hydrogen bonds. The dipolar character of 1:2.5 PβCD inclusion compound improves the solubility and the dissolution rate of piroxicam and thus its rate of absorption.

Distinct signalling properties of insulin receptor substrate (IRS)-1 and IRS-2 in mediating insulin/IGF-1 action.

Science.gov (United States)

Rabiee, Atefeh; Krüger, Marcus; Ardenkjær-Larsen, Jacob; Kahn, C Ronald; Emanuelli, Brice

2018-07-01

Insulin/IGF-1 action is driven by a complex and highly integrated signalling network. Loss-of-function studies indicate that the major insulin/IGF-1 receptor substrate (IRS) proteins, IRS-1 and IRS-2, mediate different biological functions in vitro and in vivo, suggesting specific signalling properties despite their high degree of homology. To identify mechanisms contributing to the differential signalling properties of IRS-1 and IRS-2 in the mediation of insulin/IGF-1 action, we performed comprehensive mass spectrometry (MS)-based phosphoproteomic profiling of brown preadipocytes from wild type, IRS-1 -/- and IRS-2 -/- mice in the basal and IGF-1-stimulated states. We applied stable isotope labeling by amino acids in cell culture (SILAC) for the accurate quantitation of changes in protein phosphorylation. We found ~10% of the 6262 unique phosphorylation sites detected to be regulated by IGF-1. These regulated sites included previously reported substrates of the insulin/IGF-1 signalling pathway, as well as novel substrates including Nuclear Factor I X and Semaphorin-4B. In silico prediction suggests the protein kinase B (PKB), protein kinase C (PKC), and cyclin-dependent kinase (CDK) as the main mediators of these phosphorylation events. Importantly, we found preferential phosphorylation patterns depending on the presence of either IRS-1 or IRS-2, which was associated with specific sets of kinases involved in signal transduction downstream of these substrates such as PDHK1, MAPK3, and PKD1 for IRS-1, and PIN1 and PKC beta for IRS-2. Overall, by generating a comprehensive phosphoproteomic profile from brown preadipocyte cells in response to IGF-1 stimulation, we reveal both common and distinct insulin/IGF-1 signalling events mediated by specific IRS proteins. Copyright © 2018 Elsevier Inc. All rights reserved.

Infrared studies on complexes between octaethyltetraamidepyrophosphate (OETAPP) and uranyl salts

International Nuclear Information System (INIS)

Grychowski, P.; Mikulski, J.; Moravets, Ya.; Shara, V.; Shourkova, L.

1981-01-01

Uranyl nitrate and uranyl chloride were extracted from the water phase with CHCl 3 solution of octaethyltetraamidepyrophosphate (OETAPP). Infrared spectra of the organic phases were recorded before and after the extraction. For both systems, the frequency of the P=O stretching mode of OETAPP after the extraction was lowered, which indicates for the formation of OETAPP UO 2 (NO 3 ) 2 and OETAPP UO 2 Cl 2 complexes. If uranyl nitrate was extracted with OETAPP in CCl 4 a precipitate was formed in the solution. From the analysis of the IR spectrum of the precipitate it was concluded that the complex OETAPP UO 2 (NO 3 ) 2 was formed also in this case, however, the complex was insoluble in CCl 4 . (author)

Exploring inclusion complexes of ionic liquids with α- and β- cyclodextrin by NMR, IR, mass, density, viscosity, surface tension and conductance study

Science.gov (United States)

Barman, Biraj Kumar; Rajbanshi, Biplab; Yasmin, Ananya; Roy, Mahendra Nath

2018-05-01

The formation of the host-guest inclusion complexes of ionic liquids namely [BMIm]Cl and [HMIm]Cl with α-CD and β-CD were studied by means of physicochemical and spectroscopic methods. Conductivity and surface tension study were in good agreement with the 1H NMR and FT-IR studies which confirm the formation of the inclusion complexes. The Density and viscosity study also supported the formation of the ICs. Further the stoichiometry was determined 1:1 for each case and the association constants and thermodynamic parameters derived supported the most feasible formation of the [BMIm]Cl- β-CD inclusion complex.

Synthesis and IR spectral study of MoO2Cl2 molecular complex with acetoacetanilides. Crystal structure of MoO2Cl2 complex with acetoacet-2-toluidine

International Nuclear Information System (INIS)

Abramenko, V.L.; Sergienko, V.S.; Churakov, A.V.

2000-01-01

Certain MoO 2 Cl 2 complexes with acetoacetanilide derivatives were synthesized, two IR spectral study being performed. Crystal and molecular structure of MoO 2 Cl 2 complex with acetoacet-2-toluidine (HL) was determined using X-ray diffraction analysis. The crystals are monoclinic, a = 7.621 (7), b = 9.498 (3), c = 19.980 (9) A, β = 95.16 (7), Z = 4, sp.gr. P2 1 /n. Coordination polyhedron of Mo atom is a distorted octahedron with two O oxoatoms in cis-position, two Cl atom in mutual trans-position and two O(HL) atoms in trans-positions in reference to O(oxo) [ru

Chlorination of (PheboxIr(mesityl(OAc by Thionyl Chloride

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Meng Zhou

2015-06-01

Full Text Available Pincer (PheboxIr(mesityl(OAc (2 (Phebox = 3,5-dimethylphenyl-2,6-bis(oxazolinyl complex, formed by benzylic C-H activation of mesitylene (1,3,5-trimethylbenzene using (PheboxIr(OAc2OH2 (1, was treated with thionyl chloride to rapidly form 1-(chloromethyl-3,5-dimethylbenzene in 50% yield at 23 °C. A green species was obtained at the end of reaction, which decomposed during flash column chromatography to form (PheboxIrCl2OH2 in 87% yield.

Photodissociation Spectroscopy of Cold Protonated Synephrine: Surprising Differences between IR-UV Hole-Burning and IR Photodissociation Spectroscopy of the O-H and N-H Modes.

Science.gov (United States)

Nieuwjaer, N; Desfrançois, C; Lecomte, F; Manil, B; Soorkia, S; Broquier, M; Grégoire, G

2018-04-19

We report the UV and IR photofragmentation spectroscopies of protonated synephrine in a cryogenically cooled Paul trap. Single (UV or IR) and double (UV-UV and IR-UV) resonance spectroscopies have been performed and compared to quantum chemistry calculations, allowing the assignment of the lowest-energy conformer with two rotamers depending on the orientation of the phenol hydroxyl (OH) group. The IR-UV hole burning spectrum exhibits the four expected vibrational modes in the 3 μm region, i.e., the phenol OH, C β -OH, and two NH 2 + stretches. The striking difference is that, among these modes, only the free phenol OH mode is active through IRPD. The protonated amino group acts as a proton donor in the internal hydrogen bond and displays large frequency shifts upon isomerization expected during the multiphoton absorption process, leading to the so-called IRMPD transparency. More interestingly, while the C β -OH is a proton acceptor group with moderate frequency shift for the different conformations, this mode is still inactive through IRPD.

THE STUDY OF CLINOPTILOLITE MODIFIED WITH3d METALS HALIDES BY IR AND DIFFUSE REFLECTANCE SPECTROSCOPY

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T. L. Rakitskaya

2015-11-01

Full Text Available The results of investigation of natural clinoptilolite (N-CLI and that modified with 3d metal halides (MeCl2/N-CLI, where Me are Cu, Co, and Mn by IR and diffuse reflectance spectroscopy are summarized. A band at 3437 cm-1 assigned to stretching vibrations of hydroxyl groups (nOH is found in the IR spectrum of the N-CLI sample. A location of the band was practically the same as for all above MeCl2/N-CLI samples. A band of middle intensity at 1638 cm-1 in the range of deformation vibrations of zeolite water observed in the IR spectrum of N-CLI slightly displays to lower frequencies in the case of the modified samples. An intensive wide band of a complex shape in the range from 1250 to 980 cm-1 assigned to Si–O–Si and Si–O–Al vibrations appears in IR spectra of all samples. A doublet band of middle intensity at 797 and 778 cm-1 is assigned to external symmetric stretching T-O vibrations and a band at 606 cm-1-to vibrations of a double ring. A location of the above bands is the same for all listed samples but their intensity is higher for MnCl2/N-CLI and CoCl2/N-CLI samples. After the reaction with ozone, significant changes in the IR spectra are observed only for MnCl2/N-CLI. They are due to MnO2 formation on the clinoptilolite surface resulting in a high frequency displacement of some bands. Based on UV-vi spectroscopy results, it is reasonable to make conclusions about the coordination and valence state of a central atom in the MeCl2/N-CLI samples under study. A location of charge transfer bands for these samples only slightly differs from that for N-CLI however the intensity of such bands increases for the MeCl2/N-CLI samples. The UV-vis spectrum of MnCl2/N-CLI changes after the reaction with ozone: the appearance of new bands of  charge transfer at 363 and 354 nm and also the two-fold increase in intensity of a charge transfer band at 272 nm in comparison with those of N-CLI and MnCl2/N-CLI are the evidence of change in both the

IR spectral analysis for the diagnostics of crust earthquake precursors

Science.gov (United States)

Umarkhodgaev, R. M.; Liperovsky, V. A.; Mikhailin, V. V.; Meister, C.-V.; Naumov, D. Ju

2012-04-01

In regions of future earthquakes, a few days before the seismic shock, the emanation of radon and hydrogen is being observed, which causes clouds of increased ionisation in the atmosphere. In the present work the possible diagnostics of these clouds using infrared (IR) spectroscopy is considered, which may be important and useful for the general geophysical system of earthquake prediction and the observation of industrial emissions of radioactive materials into the atmosphere. Some possible physical processes are analysed, which cause, under the condition of additional ionisation in a pre-breakdown electrical field, emissions in the IR interval. In doing so, the transparency region of the IR spectrum at wavelengths of 7-15 μm is taken into account. This transparency region corresponds to spectral lines of small atmospheric constituents like CH4, CO2, N2O, NO2, NO, and O3. The possible intensities of the IR emissions observable in laboratories and in nature are estimated. The acceleration process of the electrons in the pre-breakdown electrical field before its adhesion to the molecules is analysed. The laboratory equipment for the investigation of the IR absorption spectrum is constructed for the cases of normal and decreased atmospheric pressures. The syntheses of ozone and nitrous oxides are performed in the barrier discharge. It is studied if the products of the syntheses may be used to model atmospheric processes where these components take part. Spectra of products of the syntheses in the wavelength region of 2-10 μm are observed and analysed. A device is created for the syntheses and accumulation of nitrous oxides. Experiments to observe the IR-spectra of ozone and nitrous oxides during the syntheses and during the further evolution of these molecules are performed. For the earthquake prediction, practically, the investigation of emission spectra is most important, but during the laboratory experiments, the radiation of the excited molecules is shifted by a

How Stimulus and Task Complexity Affect Monitoring in High-Functioning Adults with Autism Spectrum Disorder

NARCIS (Netherlands)

Koolen, S.; Vissers, C.T.W.M.; Egger, J.I.M.; Verhoeven, L.T.W.

2014-01-01

The present study examined whether individuals with autism spectrum disorder (ASD) are able to update and monitor working memory representations of visual input, and whether performance is influenced by stimulus and task complexity. 15 high-functioning adults with ASD and 15 controls were asked to

Combined IR-Raman vs vibrational sum-frequency heterospectral correlation spectroscopy

Science.gov (United States)

Roy, Sandra; Beutier, Clémentine; Hore, Dennis K.

2018-06-01

Vibrational sum-frequency generation spectroscopy is a valuable probe of surface structure, particularly when the same molecules are present in one of the adjacent bulk solid or solution phases. As a result of the non-centrosymmetric requirement of SFG, the signal generated is a marker of the extent to which the molecules are ordered in an arrangement that breaks the up-down symmetry at the surface. In cases where the accompanying changes in the bulk are of interest in understanding and interpreting the surface structure, simultaneous analysis of the bulk IR absorption or bulk Raman scattering is helpful, and may be used in heterospectral surface-bulk two-dimensional correlation. We demonstrate that, in such cases, generating a new type of bulk spectrum that combines the IR and Raman amplitudes is a better candidate than the individual IR and Raman spectra for the purpose of correlation with the SFG signal.

IR spectral analysis for the diagnostics of crust earthquake precursors

Directory of Open Access Journals (Sweden)

R. M. Umarkhodgaev

2012-11-01

Full Text Available Some possible physical processes are analysed that cause, under the condition of additional ionisation in a pre-breakdown electric field, emissions in the infrared (IR interval. The atmospheric transparency region of the IR spectrum at wavelengths of 7–15 μm is taken into account. This transparency region corresponds to spectral lines of small atmospheric constituents like CH₄, CO₂, N₂O, NO₂, NO, and O₃. The possible intensities of the IR emissions observable in laboratories and in nature are estimated. The acceleration process of the electrons in the pre-breakdown electrical field before its adhesion to the molecules is analyzed. For daytime conditions, modifications of the adsorption spectra of the scattered solar emissions are studied; for nighttime, variations of emission spectra may be used for the analysis.

From UV/IR mixing to closed strings

International Nuclear Information System (INIS)

Lopez, Esperanza

2003-01-01

It was shown in [1] that the leading UV/IR mixing effects in noncommutative gauge theories on D-branes are able to capture information about the closed string spectrum of the parent string theory. The analysis was carried out for D-branes on nonsupersymmetric C 3 /Z N orbifolds of Type IIB. In this paper we consider D-branes on twisted circles compactifications of Type II string theory. We find that the signs of the leading UV/IR mixing effects know about the (mass) 2 gap between the lowest modes in NSNS and RR closed string towers. Moreover, the relevant piece of the field theory effective action can be reproduced purely in the language of closed strings. Remarkably, this approach unifies in a single structure, that of a closed string exchange between D-branes, both the leading planar and nonplanar effects associated to the absence of supersymmetry. (author)

2-(2′-Pyridyl)-4,6-diphenylphosphinine versus 2-(2′-Pyridyl)-4,6-diphenylpyridine: Synthesis, Characterization, and Reactivity of Cationic RhIII and IrIII Complexes Based on Aromatic Phosphorus Heterocycles

NARCIS (Netherlands)

de Krom, I.; Broeckx, L.E.E.; Lutz, M.; Müller, Christian

2013-01-01

The bidentate P,N hybrid ligand 1 allows access for the first time to novel cationic phosphinine-based RhIII and IrIII complexes, broadening significantly the scope of low-coordinate aromatic phosphorus heterocycles for potential applications. The coordination chemistry of 1 towards RhIII and IrIII

Alkoholio ir tabako pasiūlos ir paklausos teisinio reguliavimo raida Lietuvos Respublikoje: problemos ir sprendimai

OpenAIRE

Mockevičius, Arminas

2014-01-01

Viešosios teisės magistro studijų programos studento Armino Mockevičiaus buvo parašytas magistro baigiamasis darbas „Alkoholio ir tabako pasiūlos ir paklausos teisinio reguliavimo raida Lietuvos Respublikoje: problemos ir sprendimai“. Šis darbas parašytas Vilniuje, 2014 metais, Mykolo Romerio universiteto Teisės fakulteto Konstitucinės ir administracinės teisės institute, vadovaujant dr. Gintautui Vilkeliui, apimtis 98 p. Darbo tikslas yra atskleisti alkoholio ir tabako pasiūlos ir paklau...

Effects of virtual isobar admixtures on the low-energy spectrum of a complex nucleus - model calculations for 12C

International Nuclear Information System (INIS)

Grecksch, E.

1978-01-01

On the basis of a detailed analysis of the excitation spectrum of a complex nucleus in the framework of the conventional shell model theory, the paper extends this concept by adding nucleonic degrees of freedom (isobars) and by model investigations and a realistic assessment of their effects on the excited states of the low-energy spectrum. (AH) [de

Stacking reactions of the borole complex Cp*Rh(η5-C4H4BPh) with the dicationic fragments [Cp*M]2+ (M = Rh or Ir)

International Nuclear Information System (INIS)

Loginov, D.A.; Muratov, D.V.; Starikova, Z.A.; Petrovskij, P.V.; Kudinov, A.R.

2006-01-01

The reaction of the (borole)rhodium iodide complex [(η-C 4 H 4 BPh)RhI] 4 with Cp*Li afforded the sandwich compound Cp*Rh(η-C 4 H 4 BPh) (1). The reactions of compound 1 with the solvated complexes [Cp*M(MeNO 2 ) 3 ] 2+ (BF 4 - ) 2 gave triple-decker cationic complexes with the central borole ligand [Cp*Rh(μ-η 5 :η 5 -C 4 H 4 BPh)MCp*] 2+ (BF 4 - ) 2 (M = Rh or Ir). The structure of complex 1 was established by X-ray diffraction [ru

Laser desorption single-conformation UV and IR spectroscopy of the sulfonamide drug sulfanilamide, the sulfanilamide-water complex, and the sulfanilamide dimer.

Science.gov (United States)

Uhlemann, Thomas; Seidel, Sebastian; Müller, Christian W

2017-06-07

We have studied the conformational preferences of the sulfonamide drug sulfanilamide, its dimer, and its monohydrated complex through laser desorption single-conformation UV and IR spectroscopy in a molecular beam. Based on potential energy curves for the inversion of the anilinic and the sulfonamide NH 2 groups calculated at DFT level, we suggest that the zero-point level wave function of the sulfanilamide monomer is appreciably delocalized over all four conformer wells. The sulfanilamide dimer, and the monohydrated complex each exhibit a single isomer in the molecular beam. The isomeric structures of the sulfanilamide dimer and the monohydrated sulfanilamide complex were assigned based on their conformer-specific IR spectra in the NH and OH stretch region. Quantum Theory of Atoms in Molecules (QTAIM) analysis of the calculated electron density in the water complex suggests that the water molecule is bound side-on in a hydrogen bonding pocket, donating one O-HO[double bond, length as m-dash]S hydrogen bond and accepting two hydrogen bonds, a NHO and a CHO hydrogen bond. QTAIM analysis of the dimer electron density suggests that the C i symmetry dimer structure exhibits two dominating N-HO[double bond, length as m-dash]S hydrogen bonds, and three weaker types of interactions: two CHO bonds, two CHN bonds, and a chalcogen OO interaction. Most interestingly, the molecular beam dimer structure closely resembles the R dimer unit - the dimer unit with the greatest interaction energy - of the α, γ, and δ crystal polymorphs. Interacting Quantum Atoms analysis provides evidence that the total intermolecular interaction in the dimer is dominated by the short-range exchange-correlation contribution.

Supporting Individuals with Autism Spectrum Disorder in Understanding and Coping with Complex Social Emotional Issues

Science.gov (United States)

Ahlers, Kaitlyn P.; Gabrielsen, Terisa P.; Lewis, Danielle; Brady, Anna M.; Litchford, April

2017-01-01

Core deficits in autism spectrum disorder (ASD) center around social communication and behavior. For those with ASD, these deficits complicate the task of learning how to cope with and manage complex social emotional issues. Although individuals with ASD may receive sufficient academic and basic behavioral support in school settings, supports for…

PERIODIC ACCRETION INSTABILITIES IN THE PROTOSTAR L1634 IRS 7

Energy Technology Data Exchange (ETDEWEB)

Hodapp, Klaus W. [Institute for Astronomy, University of Hawaii, 640 N. Aohoku Place, Hilo, HI 96720 (United States); Chini, Rolf, E-mail: hodapp@ifa.hawaii.edu, E-mail: rolf.chini@astro.ruhr-uni-bochum.de [Astronomisches Institut, Ruhr-Universität Bochum, Universitätsstraße 150, D-44801 Bochum (Germany)

2015-11-10

The small molecular cloud Lynds 1634 contains at least three outflow sources. We found one of these, IRS 7, to be variable with a period of 37.14 ± 0.04 days and an amplitude of approximately 2 mag in the K{sub s} band. The light curve consists of a quiescent phase with little or no variation, and a rapid outburst phase. During the outburst phase, the rapid variation in brightness generates light echoes that propagate into the surrounding molecular cloud, allowing a measurement of the distance to IRS 7 of 404 pc ± 35 pc. We observed only a marginally significant change in the H − K color during the outburst phase. The K-band spectrum of IRS 7 shows CO bandhead emission but its equivalent width does not change significantly with the phase of the light curve. The H{sub 2} 1–0 S(1) line emission does not follow the variability of the continuum flux. We also used the imaging data for a proper motion study of the outflows originating from the IRS 7 and the far-infrared source IRAS 05173-0555, and confirm that these are indeed distinct outflows.

IR reflectance spectroscopy of carbon dioxide clathrate hydrates. Implications for Saturn's icy moons.

Science.gov (United States)

Oancea, A.; Grasset, O.; Le Menn, E.; Bezacier, L.; Bollengier, O.; Le Mouélic, S.; Tobie, G.

2012-04-01

A CO2 spectral band was discovered by VIMS on the Saturn's satellites Dione, Hyperion, Iapetus and Phoebe [1]. The band position on the three first satellites corresponds to CO2 trapped in a complex material, but no indication exists whether this latter is water ice or some mineral or complex organic compound [1]. On Phoebe, the CO2 spectral band is consistent with solid CO2 or CO2 molecules trapped in the small cages of a clathrate hydrate structure [2]. It is thought that clathrate hydrates could play a significant role in the chemistry of the solar nebula [3] and in the physical evolution of astrophysical objects [4]. But so far, no clathrate hydrate structure has been observed in astrophysical environments. Moreover, identification of molecules trapped in a clathrate hydrate structure is extremely difficult because of the strong IR vibration modes of the water ice matrix. In this work, experimental IR reflectance spectra for CO2 clathrate hydrates are studied on grains and films. Clathrates are synthesized in a high pressure autoclave at low temperatures. IR spectral analysis is made with a low pressure and low temperature cryostat. These experimental conditions - 80 spectrum will be presented. A comparison between the absorption bands of CO2 clathrate hydrates obtained in our lab and CO2 absorption bands as detected by VIMS on the icy satellites of Saturn will be shown. This experimental work confirms that VIMS data are not consistent with the presence of structure I CO2 clathrate hydrates on the surface of the icy moons. Possibility of having metastable structure II still remains unsolved and will be discussed. [1] Dalton et al., Space Sci. Rev. 2010, 153 : 113-154. [2] Cruikshank D.P. et al, Icarus, 2010, 206: 561-572. [3] Mousis O. et al , Ap. J. 2009, 691: 1780-1786. [4] Choukroun M. et al, in Solar System Ices, edited by Castillo-Rogez, J. et al., 2011.

The application of FT-IR spectrum method in photocuring process for polyester acrylate

International Nuclear Information System (INIS)

Cao Jin; Lu Xianliang; Zhang Zhenli

1995-01-01

This paper describes that the UV curing process of polyester acrylate can be monitored by measuring the degree of double bonds conversion with FT-IR spectroscopy. The various factors effect the UV curing rate. The relation between the curing rate and the concentration of photoinitiator, crosslinking agent, UV light intensity was discussed. (author)

Hydrogen storage and evolution catalysed by metal hydride complexes.

Science.gov (United States)

Fukuzumi, Shunichi; Suenobu, Tomoyoshi

2013-01-07

The storage and evolution of hydrogen are catalysed by appropriate metal hydride complexes. Hydrogenation of carbon dioxide by hydrogen is catalysed by a [C,N] cyclometalated organoiridium complex, [Ir(III)(Cp*)(4-(1H-pyrazol-1-yl-κN(2))benzoic acid-κC(3))(OH(2))](2)SO(4) [Ir-OH(2)](2)SO(4), under atmospheric pressure of H(2) and CO(2) in weakly basic water (pH 7.5) at room temperature. The reverse reaction, i.e., hydrogen evolution from formate, is also catalysed by [Ir-OH(2)](+) in acidic water (pH 2.8) at room temperature. Thus, interconversion between hydrogen and formic acid in water at ambient temperature and pressure has been achieved by using [Ir-OH(2)](+) as an efficient catalyst in both directions depending on pH. The Ir complex [Ir-OH(2)](+) also catalyses regioselective hydrogenation of the oxidised form of β-nicotinamide adenine dinucleotide (NAD(+)) to produce the 1,4-reduced form (NADH) under atmospheric pressure of H(2) at room temperature in weakly basic water. In weakly acidic water, the complex [Ir-OH(2)](+) also catalyses the reverse reaction, i.e., hydrogen evolution from NADH to produce NAD(+) at room temperature. Thus, interconversion between NADH (and H(+)) and NAD(+) (and H(2)) has also been achieved by using [Ir-OH(2)](+) as an efficient catalyst and by changing pH. The iridium hydride complex formed by the reduction of [Ir-OH(2)](+) by H(2) and NADH is responsible for the hydrogen evolution. Photoirradiation (λ > 330 nm) of an aqueous solution of the Ir-hydride complex produced by the reduction of [Ir-OH(2)](+) with alcohols resulted in the quantitative conversion to a unique [C,C] cyclometalated Ir-hydride complex, which can catalyse hydrogen evolution from alcohols in a basic aqueous solution (pH 11.9). The catalytic mechanisms of the hydrogen storage and evolution are discussed by focusing on the reactivity of Ir-hydride complexes.

Characterization and identification of microorganisms by FT-IR microspectrometry

Science.gov (United States)

Ngo-Thi, N. A.; Kirschner, C.; Naumann, D.

2003-12-01

We report on a novel FT-IR approach for microbial characterization/identification based on a light microscope coupled to an infrared spectrometer which offers the possibility to acquire IR-spectra of microcolonies containing only few hundred cells. Microcolony samples suitable for FT-IR microspectroscopic measurements were obtained by a replica technique with a stamping device that transfers spatially accurate cells of microcolonies growing on solid culture plates to a special, IR-transparent or reflecting stamping plate. High quality spectra could be recorded either by applying the transmission/absorbance or the reflectance/absorbance mode of the infrared microscope. Signal to noise ratios higher than 1000 were obtained for microcolonies as small as 40 μm in diameter. Reproducibility levels were established that allowed species and strain identification. The differentiation and classification capacity of the FT-IR microscopic technique was tested for different selected microorganisms. Cluster and factor analysis methods were used to evaluate the complex spectral data. Excellent discrimination between bacteria and yeasts, and at the same time Gram-negative and Gram-positive bacterial strains was obtained. Twenty-two selected strains of different species within the genus Staphylococcus were repetitively measured and could be grouped into correct species cluster. Moreover, the results indicated that the method allows also identifications at the subspecies level. Additionally, the new approach allowed spectral mapping analysis of single colonies which provided spatially resolved characterization of growth heterogeneity within complex microbial populations such as colonies.

Ligand-bridged dinuclear cyclometalated Ir(III) complexes: from metallamacrocycles to discrete dimers.

Science.gov (United States)

Chandrasekhar, Vadapalli; Hajra, Tanima; Bera, Jitendra K; Rahaman, S M Wahidur; Satumtira, Nisa; Elbjeirami, Oussama; Omary, Mohammad A

2012-02-06

Metallamacrocycles 1, 2, and 3 of the general formula [{Ir(ppy)(2)}(2)(μ-BL)(2)](OTf)(2) (ppyH = 2-phenyl pyridine; BL = 1,2-bis(4-pyridyl)ethane (bpa) (1), 1,3-bis(4-pyridyl)propane (bpp) (2), and trans-1,2-bis(4-pyridyl)ethylene (bpe) (3)) have been synthesized by the reaction of [{(ppy)(2)Ir}(2)(μ-Cl)(2)], first with AgOTf to effect dechlorination and later with various bridging ligands. Open-frame dimers [{Ir(ppy)(2)}(2)(μ-BL)](OTf)(2) were obtained in a similar manner by utilizing N,N'-bis(2-pyridyl)methylene-hydrazine (abp) and N,N'-(bis(2-pyridyl)formylidene)ethane-1,2-diamine (bpfd) (for compounds 4 and 5, respectively) as bridging ligands. Molecular structures of 1, 3, 4, and 5 were established by X-ray crystallography. Cyclic voltammetry experiments reveal weakly interacting "Ir(ppy)(2)" units bridged by ethylene-linked bpe ligand in 3; on the contrary the metal centers are electronically isolated in 1 and 2 where the bridging ligands are based on ethane and propane linkers. The dimer 4 exhibits two accessible reversible reduction couples separated by 570 mV indicating the stability of the one-electron reduced species located on the diimine-based bridge abp. The "Ir(ppy)(2)" units in compound 5 are noninteracting as the electronic conduit is truncated by the ethane spacer in the bpfd bridge. The dinuclear compounds 1-5 show ligand centered (LC) transitions involving ppy ligands and mixed metal to ligand/ligand to ligand charge transfer (MLCT/LLCT) transitions involving both the cyclometalating ppy and bridging ligands (BL) in the UV-vis spectra. For the conjugated bridge bpe in compound 3 and abp in compound 4, the lowest-energy charge-transfer absorptions are red-shifted with enhanced intensity. In accordance with their similar electronic structures, compounds 1 and 2 exhibit identical emissions. The presence of vibronic structures in these compounds indicates a predominantly (3)LC excited states. On the contrary, broad and unstructured

Synthesis, Characterization, and Physicochemical Studies of Mixed Ligand Complexes of Inner Transition Metals with Lansoprazole and Cytosine

Directory of Open Access Journals (Sweden)

Sarika Verma

2013-01-01

Full Text Available Few complexes of inner transition metals [Th(IV, Ce(IV, Nd(III, Gd(III] have been synthesized by reacting their metal salts with lansoprazole, 2-([3-methyl-4-(2,2,2-trifluoroethoxypyridin-2-yl]methylsulfinyl-1H-benzoimidazole and cytosine. All the complexes were synthesized in ethanolic medium. The yield percentage rangs from 80 to 90%. The complexes are coloured solids. The complexes were characterized through elemental analyses, conductance measurements, and spectroscopic methods (FT IR, FAB Mass, 1H NMR and UV. An IR spectrum indicates that the ligand behaves as bidentate ligands. The metal complexes have been screened for their antifungal activity towards Aspergillus niger fungi. The interaction of inner transition metals with lansoprazole, in presence of cytosine, has also been investigated potentiometrically at two different temperatures 26±1°C and 36±1°C and at 0.1 M (KNO3 ionic strength. The stability constants of ternary complexes indicate the stability order as Th(IV < Ce(IV < Gd(III < Nd(III. logK values obtained are positive and suggest greater stabilization of ternary complexes. The values of thermodynamic parameters (free energy (ΔG, enthalpy (ΔH, and entropy (ΔS are also calculated.

APPL1 potentiates insulin sensitivity by facilitating the binding of IRS1/2 to the insulin receptor.

Science.gov (United States)

Ryu, Jiyoon; Galan, Amanda K; Xin, Xiaoban; Dong, Feng; Abdul-Ghani, Muhammad A; Zhou, Lijun; Wang, Changhua; Li, Cuiling; Holmes, Bekke M; Sloane, Lauren B; Austad, Steven N; Guo, Shaodong; Musi, Nicolas; DeFronzo, Ralph A; Deng, Chuxia; White, Morris F; Liu, Feng; Dong, Lily Q

2014-05-22

Binding of insulin receptor substrate proteins 1 and 2 (IRS1/2) to the insulin receptor (IR) is essential for the regulation of insulin sensitivity and energy homeostasis. However, the mechanism of IRS1/2 recruitment to the IR remains elusive. Here, we identify adaptor protein APPL1 as a critical molecule that promotes IRS1/2-IR interaction. APPL1 forms a complex with IRS1/2 under basal conditions, and this complex is then recruited to the IR in response to insulin or adiponectin stimulation. The interaction between APPL1 and IR depends on insulin- or adiponectin-stimulated APPL1 phosphorylation, which is greatly reduced in insulin target tissues in obese mice. appl1 deletion in mice consistently leads to systemic insulin resistance and a significant reduction in insulin-stimulated IRS1/2, but not IR, tyrosine phosphorylation, indicating that APPL1 sensitizes insulin signaling by acting at a site downstream of the IR. Our study uncovers a mechanism regulating insulin signaling and crosstalk between the insulin and adiponectin pathways. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Syntheses and luminescence properties of two novel lanthanide (III) perchlorate complexes with phenacyl p-tolyl sulfoxide

Energy Technology Data Exchange (ETDEWEB)

Feng, Shu-Yan [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China); Li, Wen-Xian, E-mail: nmglwx@163.com [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China); Zheng, Yu-Shan [Inner Mongolia Autonomous Region Product Quality Inspection Institute, Hohhot 010070 (China); Xin, Xiao-Dong; Guo, Feng; Cao, Xiao-Fang [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China)

2015-06-15

Two novel solid binary complexes of rare earth perchlorate with phenacyl p-tolyl sulfoxide were synthesized and characterized by elemental analysis, molar conductivity, coordination titration analysis, IR, TG-DSC, {sup 1}HNMR and UV spectra. The results indicated that the composition of these complexes was REL{sub 7} (ClO{sub 4}){sub 3}·6H{sub 2}O (RE=Eu (III), Tb (III), L=C{sub 6}H{sub 5}COCH{sub 2}SOC{sub 6}H{sub 4}CH{sub 3}). The study on IR spectra and {sup 1}HNMR spectra revealed that phenacyl p-tolyl sulfoxide bonded with RE{sup 3+} ions by the oxygen atom in sulfinyl group. The emission spectra illustrated that both the Eu (III) and Tb (III) complexes displayed excellent luminescence in solid state, and The most intensive characteristic emission of the Eu(III) and Tb(III) complexes were 245,400 a.u. and 298,000 a.u. respectively. The slit with was 1 nm. By analysis luminescence and phosphorescence spectrum, it was found that the ligand had the advantage to absorb energy and transfer it to the Eu (III) and Tb (III) ions. The fluorescence lifetimes of the complexes were measured as well as the quantum yield of the Eu (III) complex.

IR-safe and UV-safe integrands in the EFTofLSS with exact time dependence

Energy Technology Data Exchange (ETDEWEB)

Lewandowski, Matthew [Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS, 91191 Gif-sur-Yvette (France); Senatore, Leonardo, E-mail: matthew.lewandowski@ipht.fr, E-mail: senatore@stanford.edu [Stanford Institute for Theoretical Physics, Stanford University, Stanford, 94306 CA (United States)

2017-08-01

Because large-scale structure surveys may very well be the next leading sources of cosmological information, it is important to have a precise understanding of the cosmological observables; for this reason, the Effective Field Theory of Large-Scale Structure (EFTofLSS) was developed. So far, most results in the EFTofLSS have used the so-called Einstein-de Sitter approximation, an approximation of the time dependence which is known to be accurate to better than one percent. However, in order to reach even higher accuracy, the full time dependence must be used. The computation with exact time dependence is sensitive to both infrared (IR) and ultraviolet (UV) effects in the loop integrands, and while these effects must cancel because of diffeomorphism invariance, they make numerical computation much less efficient. We provide a formulation of the one-loop, equal-time exact-time-dependence power spectrum of density perturbations which is manifestly free of these spurious IR and UV divergences at the level of the integrand. We extend our results to the total matter mode with clustering quintessence, show that IR and UV divergences cancel, and provide the associated IR- and UV-safe integrand. This also establishes that the consistency conditions are satisfied in this system. We then use our one-loop result to do an improved precision comparison of the two-loop dark-matter power spectrum with the Dark Sky N -body simulation.

ir overtone spectrum of the vibrational soliton in crystalline acetanilide

International Nuclear Information System (INIS)

Scott, A.C.; Gratton, E.; Shyamsunder, E.; Careri, G.

1985-01-01

The self-trapping (soliton) theory which was recently developed to account for the anomalous amide-I band at 1650 cm -1 in crystalline acetanilide (a model system for protein) has been extended to predict the anharmonicity constant of the overtone spectrum. These infrared-active overtones which have been detected at 3250, 4803, and 6304 cm -1 yield an anharmonicity constant that is in good agreement with the theory

ir overtone spectrum of the vibrational soliton in crystalline acetanilide

Science.gov (United States)

Scott, A. C.; Gratton, E.; Shyamsunder, E.; Careri, G.

1985-10-01

The self-trapping (soliton) theory which was recently developed to account for the anomalous amide-I band at 1650 cm-1 in crystalline acetanilide (a model system for protein) has been extended to predict the anharmonicity constant of the overtone spectrum. These infrared-active overtones which have been detected at 3250, 4803, and 6304 cm-1 yield an anharmonicity constant that is in good agreement with the theory.

FT-IR spectroscopy of lipoproteins—A comparative study

Science.gov (United States)

Krilov, Dubravka; Balarin, Maja; Kosović, Marin; Gamulin, Ozren; Brnjas-Kraljević, Jasminka

2009-08-01

FT-IR spectra, in the frequency region 4000-600 cm -1, of four major lipoprotein classes: very low density lipoprotein (VLDL), low density lipoprotein (LDL) and two subclasses of high density lipoproteins (HDL 2 and HDL 3) were analyzed to obtain their detailed spectral characterization. Information about the protein domain of particle was obtained from the analysis of amide I band. The procedure of decomposition and curve fitting of this band confirms the data already known about the secondary structure of two different apolipoproteins: apo A-I in HDL 2 and HDL 3 and apo B-100 in LDL and VLDL. For information about the lipid composition and packing of the particular lipoprotein the well expressed lipid bands in the spectra were analyzed. Characterization of spectral details in the FT-IR spectrum of natural lipoprotein is necessary to study the influence of external compounds on its structure.

Characterization of metal-bound water in bioactive Fe(III)-cyclophane complexes

Science.gov (United States)

Salazar-Medina, A. J.; Gámez-Corrales, R.; Ramírez, J. Z.; González-Aguilar, G. A.; Velázquez-Contreras, E. F.

2018-02-01

Binuclear Fe(III) complexes, Fe2PO and Fe2PC, have functions of antioxidants as well as superoxide dismutase and peroxidase mimickers. The role of water molecules in the non-cytotoxic properties of these complexes have been studied by thermogravimetric and IR/Raman-spectroscopic methods. The thermogravimetric analysis of Fe2PO shows the presence of nine water molecules (Fe2PO·9H2O), three of which are directly coordinated to the metallic ion; the remaining six molecules occupy the secondary coordination sphere. For Fe2PC, eight water molecules were detected (Fe2PC·8H2O), and only one of them directly coordinates to the metallic ion. IR/Raman spectrum analyses corroborate the presence of water molecules in both metallic complexes and the mode of coordination to the ligand, on the basis of bands characteristic of hydration water at ∼3300 cm-1 and bands of adsorbed water between 430 and 490 cm-1. A pentacoordinate geometry is proposed for Fe2PO and a hexacoordinated geometry for Fe2PC. Those results are consistent with theoretical calculations performed through a semiempirical PM7 method. The presence of coordinated water molecules is closely related to the reactivity of Fe2PO and Fe2PC in solution.

IR-UV double resonance spectroscopic investigation of phenylacetylene-alcohol complexes. Alkyl group induced hydrogen bond switching.

Science.gov (United States)

Singh, Prashant Chandra; Patwari, G Naresh

2008-06-12

The electronic transitions of phenylacetylene complexes with water and trifluoroethanol are shifted to the blue, while the corresponding transitions for methanol and ethanol complexes are shifted to the red relative to the phenylacetylene monomer. Fluorescence dip infrared (FDIR) spectra in the O-H stretching region indicate that, in all the cases, phenylacetylene is acting as a hydrogen bond acceptor to the alcohols. The FDIR spectrum in the acetylenic C-H stretching region shows Fermi resonance bands for the bare phenylacetylene, which act as a sensitive tool to probe the intermolecular structures. The FDIR spectra reveal that water and trifluoroethanol interact with the pi electron density of the acetylene C-C triple bond, while methanol and ethanol interact with the pi electron density of the benzene ring. It can be inferred that the hydrogen bonding acceptor site on phenylacetylene switches from the acetylene pi to the benzene pi with lowering in the partial charge on the hydrogen atom of the OH group. The most significant finding is that the intermolecular structures of water and methanol complexes are notably distinct, which, to the best of our knowledge, this is first such observation in the case of complexes of substituted benzenes.

SH2-B promotes insulin receptor substrate 1 (IRS1)- and IRS2-mediated activation of the phosphatidylinositol 3-kinase pathway in response to leptin.

Science.gov (United States)

Duan, Chaojun; Li, Minghua; Rui, Liangyou

2004-10-15

Leptin regulates energy homeostasis primarily by binding and activating its long form receptor (LRb). Deficiency of either leptin or LRb causes morbid obesity. Leptin stimulates LRb-associated JAK2, thus initiating multiple pathways including the Stat3 and phosphatidylinositol (PI) 3-kinase pathways that mediate leptin biological actions. Here we report that SH2-B, a JAK2-interacting protein, promotes activation of the PI 3-kinase pathway by recruiting insulin receptor substrate 1 (IRS1) and IRS2 in response to leptin. SH2-B directly bound, via its PH and SH2 domain, to both IRS1 and IRS2 both in vitro and in intact cells and mediated formation of a JAK2/SH2-B/IRS1 or IRS2 tertiary complex. Consequently, SH2-B dramatically enhanced leptin-stimulated tyrosine phosphorylation of IRS1 and IRS2 in HEK293 cells stably expressing LRb, thus promoting association of IRS1 and IRS2 with the p85 regulatory subunit of PI 3-kinase and phosphorylation and activation of Akt. SH2-B mutants with lower affinity for IRS1 and IRS2 exhibited reduced ability to promote association of JAK2 with IRS1, tyrosine phosphorylation of IRS1, and association of IRS1 with p85 in response to leptin. Moreover, deletion of the SH2-B gene impaired leptin-stimulated tyrosine phosphorylation of endogenous IRS1 in mouse embryonic fibroblasts (MEF), which was reversed by reintroduction of SH2-B. Similarly, SH2-B promoted growth hormone-stimulated tyrosine phosphorylation of IRS1 in both HEK293 and MEF cells. Our data suggest that SH2-B is a novel mediator of the PI 3-kinase pathway in response to leptin or other hormones and cytokines that activate JAK2.

Organodioxygen complexes of some heavy metal ions and their oxygen transfer reactions

International Nuclear Information System (INIS)

Tarafder, M.T.H.; Mei Ling; Gino Mariotto

2003-09-01

Several novel organodioxygen complexes of lanthanide ions, viz., lanthanum(m) and cerium(IV) have been synthesized containing a number of organic co- ligands. The complexes characterized were, [La(0 2 )(det)(N0 3 ) 2 ] (1), [La(O 2 )(tet)(NO 3 ) 2 ] (2), [La(O 2 )(C 5 H 5 N)2NO 3 ] (3), [La(O 2 )(C 6 H 18 N 3 PO) 2 (NO 3 ) 2 ] (4), [La(0 2 )(OPPh 3 ) 2 (N0 3 ) 2 ] (5), [La(O 2 ) 2 (NH 2 CH 2 CH 2 NH 2 ) 2 NO 3 ] (6), [La(O 2 )(PPh 3 ) 2 (NO 3 ) 2 ] (7) and [Ce(O 2 )(C 6 H 18 N 3 PO) 2 (NO 3 ) 3 ] (8). IR and Raman spectra revealed that (3) was a peroxo complex while the others were, in particular, superoxo type. The IR spectrum of (3) gives V 1 (O-O) at 851 cm -1 while the Raman spectra of (4), (5), (7) and (8) give V 1 (O 2 ) bands at 1046 cm -1 , 1032 cm 1 , 1100 cm -1 and 1046 cm -1 , respectively. The oxygen transfer reactions of two selected complexes were carried out under stoichiometric conditions. The complex containing a bidentate ligand, (6), was found to oxidize triphenylphosphine and trans-stilbene to their oxides while the complex containing tridentate ligand (1) was stable and inert towards oxidation. (author)

The gas-phase bis-uranyl nitrate complex ((UO2)2(NO3)5)-: infrared spectrum and structure

International Nuclear Information System (INIS)

Groenewold, G.S.; van Stipdonk, Michael J.; Oomens, Jos; De Jong, Wibe A.; McIlwain, Michael E.

2011-01-01

The infrared spectrum of the bis-uranyl nitrate complex ((UO 2 ) 2 (NO 3 ) 5 ) - was measured in the gas phase using multiple photon dissociation (IRMPD). Intense absorptions corresponding to the nitrate symmetric and asymmetric vibrations, and the uranyl asymmetric vibration were observed. The nitrate v 3 vibrations indicate the presence of nitrate in a bridging configuration bound to both uranyl cations, and probably two distinct pendant nitrates in the complex. The coordination environment of the nitrate ligands and the uranyl cations were compared to those in the mono-uranyl complex. Overall, the uranyl cation is more loosely coordinated in the bis-uranyl complex ((UO 2 ) 2 (NO 3 ) 5 ) - compared to the mono-complex (UO 2 (NO 3 ) 3 ) - , as indicated by a higher O-U-O asymmetric stretching (v 3 ) frequency. However, the pendant nitrate ligands are more strongly bound in the bis-complex than they are in the mono-uranyl complex, as indicated by the v 3 frequencies of the pendant nitrate, which are split into nitrosyl and O-N-O vibrations as a result of bidentate coordination. These phenomena are consistent with lower electron density donation per uranyl by the nitrate bridging two uranyl centers compared to that of a pendant nitrate in the mono-uranyl complex. The lowest energy structure predicted by density functional theory (B3LYP functional) calculations was one in which the two uranyl molecules bridged by a single nitrate coordinated in a bis-bidentate fashion. Each uranyl molecule was coordinated by two pendant nitrate ligands. The corresponding vibrational spectrum was in excellent agreement with the IRMPD measurement, confirming the structural assignment.

The gas-phase bis-uranyl nitrate complex ((UO2)2(NO3)5)-: infrared spectrum and structure

International Nuclear Information System (INIS)

Groenewold, Gary S.; van Stipdonk, Michael J.; Oomens, Jos; de Jong, Wibe; McIlwain, Michael E.

2011-01-01

The infrared spectrum of the bis-uranyl nitrate complex ((UO 2 ) 2 (NO 3 ) 5 ) - was measured in the gas phase using multiple photon dissociation (IRMPD). Intense absorptions corresponding to the nitrate symmetric and asymmetric vibrations, and the uranyl asymmetric vibration were observed. The nitrate nu3 vibrations indicate the presence of nitrate in a bridging configuration bound to both uranyl cations, and probably two distinct pendant nitrates in the complex. The coordination environment of the nitrate ligands and the uranyl cations were compared to those in the mono-uranyl complex. Overall, the uranyl cation is more loosely coordinated in the bis-uranyl complex ((UO 2 ) 2 (NO 3 ) 5 ) - compared to the mono-complex (UO 2 (NO 3 ) 3 ) - , as indicated by a higher O-U-O asymmetric stretching (nu3) frequency. However, the pendant nitrate ligands are more strongly bound in the bis-complex than they are in the mono-uranyl complex, as indicated by the ν 3 frequencies of the pendant nitrate, which are split into nitrosyl and O-N-O vibrations as a result of bidentate coordination. These phenomena are consistent with lower electron density donation per uranyl by the nitrate bridging two uranyl centers compared to that of a pendant nitrate in the mono-uranyl complex. The structure was calculated using density functional theory (B3LYP functional), which produced a structure in which the two uranyl molecules bridged by a single nitrate coordinated in a bis-bidentate fashion. Each uranyl molecule was coordinated by two pendant nitrate ligands. The corresponding vibrational spectrum was in excellent agreement with the IRMPD measurement, confirming the structural assignment.

Addressing the Needs of Adolescents with Autism Spectrum Disorder: Considerations and Complexities for High School Interventions

Science.gov (United States)

Kucharczyk, Suzanne; Reutebuch, Colleen K.; Carter, Erik W.; Hedges, Susan; El Zein, Farah; Gustafson, Jenny R.

2015-01-01

The outcomes of students with autism spectrum disorder (ASD) are driving the field to address how secondary education might be optimally designed and delivered. We conducted 28 focus groups across four states to explore the contexts, considerations, and complexities associated with delivering and combining evidence-based interventions to meet the…

Grb-IR: A SH2-Domain-Containing Protein that Binds to the Insulin Receptor and Inhibits Its Function

Science.gov (United States)

Liu, Feng; Roth, Richard A.

1995-10-01

To identify potential signaling molecules involved in mediating insulin-induced biological responses, a yeast two-hybrid screen was performed with the cytoplasmic domain of the human insulin receptor (IR) as bait to trap high-affinity interacting proteins encoded by human liver or HeLa cDNA libraries. A SH2-domain-containing protein was identified that binds with high affinity in vitro to the autophosphorylated IR. The mRNA for this protein was found by Northern blot analyses to be highest in skeletal muscle and was also detected in fat by PCR. To study the role of this protein in insulin signaling, a full-length cDNA encoding this protein (called Grb-IR) was isolated and stably expressed in Chinese hamster ovary cells overexpressing the human IR. Insulin treatment of these cells resulted in the in situ formation of a complex of the IR and the 60-kDa Grb-IR. Although almost 75% of the Grb-IR protein was bound to the IR, it was only weakly tyrosine-phosphorylated. The formation of this complex appeared to inhibit the insulin-induced increase in tyrosine phosphorylation of two endogenous substrates, a 60-kDa GTPase-activating-protein-associated protein and, to a lesser extent, IR substrate 1. The subsequent association of this latter protein with phosphatidylinositol 3-kinase also appeared to be inhibited. These findings raise the possibility that Grb-IR is a SH2-domain-containing protein that directly complexes with the IR and serves to inhibit signaling or redirect the IR signaling pathway.

Facile Dehydrogenation of Ethane on the IrO2(110) Surface.

Science.gov (United States)

Bian, Yingxue; Kim, Minkyu; Li, Tao; Asthagiri, Aravind; Weaver, Jason F

2018-02-21

Realizing the efficient and selective conversion of ethane to ethylene is important for improving the utilization of hydrocarbon resources, yet remains a major challenge in catalysis. Herein, ethane dehydrogenation on the IrO 2 (110) surface is investigated using temperature-programmed reaction spectroscopy (TPRS) and density functional theory (DFT) calculations. The results show that ethane forms strongly bound σ-complexes on IrO 2 (110) and that a large fraction of the complexes undergo C-H bond cleavage during TPRS at temperatures below 200 K. Continued heating causes as much as 40% of the dissociated ethane to dehydrogenate and desorb as ethylene near 350 K, with the remainder oxidizing to CO x species. Both TPRS and DFT show that ethylene desorption is the rate-controlling step in the conversion of ethane to ethylene on IrO 2 (110) during TPRS. Partial hydrogenation of the IrO 2 (110) surface is found to enhance ethylene production from ethane while suppressing oxidation to CO x species. DFT predicts that hydrogenation of reactive oxygen atoms of the IrO 2 (110) surface effectively deactivates these sites as H atom acceptors, and causes ethylene desorption to become favored over further dehydrogenation and oxidation of ethane-derived species. The study reveals that IrO 2 (110) exhibits an exceptional ability to promote ethane dehydrogenation to ethylene near room temperature, and provides molecular-level insights for understanding how surface properties influence selectivity toward ethylene production.

Complexity of the AdS soliton

Science.gov (United States)

Reynolds, Alan P.; Ross, Simon F.

2018-05-01

We consider the holographic complexity conjectures in the context of the AdS soliton, which is the holographic dual of the ground state of a field theory on a torus with antiperiodic boundary conditions for fermions on one cycle. The complexity is a non-trivial function of the size of the circle with antiperiodic boundary conditions, which sets an IR scale in the dual geometry. We find qualitative differences between the calculations of complexity from spatial volume and action (CV and CA). In the CV calculation, the complexity for antiperiodic boundary conditions is smaller than for periodic, and decreases monotonically with increasing IR scale. In the CA calculation, the complexity for antiperiodic boundary conditions is larger than for periodic, and initially increases with increasing IR scale, eventually decreasing to zero as the IR scale becomes of order the UV cutoff. We compare these results to a simple calculation for free fermions on a lattice, where we find the complexity for antiperiodic boundary conditions is larger than for periodic.

X-ray diffraction, inelastic neutron scattering (INS) and infrared (IR) studies on 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex

Energy Technology Data Exchange (ETDEWEB)

Pawlukojc, A. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Sawka-Dobrowolska, W. [Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw (Poland); Bator, G. [Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw (Poland); Sobczyk, L. [Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw (Poland)], E-mail: sobczyk@chem.uni.wroc.pl; Grech, E. [Institute of Chemistry and Environmental Protection, Szczecin University of Technology, Piastow Al. 12, 71-065 Szczecin (Poland); Nowicka-Scheibe, J. [Institute of Chemistry and Environmental Protection, Szczecin University of Technology, Piastow Al. 12, 71-065 Szczecin (Poland)

2006-09-11

The structure of the 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex was determined at 100 K. In the crystalline lattice the molecules of HMB (D) and TCNE (A) are arranged in DDADDADD stacks along the b-axis. Based on the red shift of the {nu}(C{identical_to}N) IR frequencies the charge transfer (CT) degree (Z) was estimated to be equal to 0.14. It is markedly higher than that for the complex of HMB with tetracyanoquinodimethane (TCNQ) for which Z = 0.06. The analysis of vibrational modes connected with torsional motion in the low frequency region was performed based on the inelastic neutron scattering (INS) experiments and DFT theoretical calculations. The correlation between {nu} {sub exp}/{nu} {sub calc} and {nu} {sub calc} shows a deviation of experimental values from calculated ones. It is the higher the lower is the frequency of the analysed mode. The comparison of correlations for neat HMB and its complexes with TCNQ and TCNE suggests that some role in decreasing the barrier to rotation can be played by the charge transfer between D and A molecules.

X-ray diffraction, inelastic neutron scattering (INS) and infrared (IR) studies on 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex

International Nuclear Information System (INIS)

Pawlukojc, A.; Sawka-Dobrowolska, W.; Bator, G.; Sobczyk, L.; Grech, E.; Nowicka-Scheibe, J.

2006-01-01

The structure of the 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex was determined at 100 K. In the crystalline lattice the molecules of HMB (D) and TCNE (A) are arranged in DDADDADD stacks along the b-axis. Based on the red shift of the ν(C≡N) IR frequencies the charge transfer (CT) degree (Z) was estimated to be equal to 0.14. It is markedly higher than that for the complex of HMB with tetracyanoquinodimethane (TCNQ) for which Z = 0.06. The analysis of vibrational modes connected with torsional motion in the low frequency region was performed based on the inelastic neutron scattering (INS) experiments and DFT theoretical calculations. The correlation between ν exp /ν calc and ν calc shows a deviation of experimental values from calculated ones. It is the higher the lower is the frequency of the analysed mode. The comparison of correlations for neat HMB and its complexes with TCNQ and TCNE suggests that some role in decreasing the barrier to rotation can be played by the charge transfer between D and A molecules

X-ray diffraction, inelastic neutron scattering (INS) and infrared (IR) studies on 2:1 hexamethylbenzene (HMB) tetracyanoethylene (TCNE) complex

Science.gov (United States)

Pawlukojć, A.; Sawka-Dobrowolska, W.; Bator, G.; Sobczyk, L.; Grech, E.; Nowicka-Scheibe, J.

2006-09-01

The structure of the 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex was determined at 100 K. In the crystalline lattice the molecules of HMB (D) and TCNE (A) are arranged in DDADDADD stacks along the b-axis. Based on the red shift of the ν(C tbnd N) IR frequencies the charge transfer (CT) degree ( Z) was estimated to be equal to 0.14. It is markedly higher than that for the complex of HMB with tetracyanoquinodimethane (TCNQ) for which Z = 0.06. The analysis of vibrational modes connected with torsional motion in the low frequency region was performed based on the inelastic neutron scattering (INS) experiments and DFT theoretical calculations. The correlation between νexp/ νcalc and νcalc shows a deviation of experimental values from calculated ones. It is the higher the lower is the frequency of the analysed mode. The comparison of correlations for neat HMB and its complexes with TCNQ and TCNE suggests that some role in decreasing the barrier to rotation can be played by the charge transfer between D and A molecules.

Curcumin-β-cyclodextrin inclusion complex: stability, solubility, characterisation by FT-IR, FT-Raman, X-ray diffraction and photoacoustic spectroscopy, and food application.

Science.gov (United States)

Mangolim, Camila Sampaio; Moriwaki, Cristiane; Nogueira, Ana Claudia; Sato, Francielle; Baesso, Mauro Luciano; Neto, Antônio Medina; Matioli, Graciette

2014-06-15

Curcumin was complexed with β-CD using co-precipitation, freeze-drying and solvent evaporation methods. Co-precipitation enabled complex formation, as indicated by the FT-IR and FT-Raman techniques via the shifts in the peaks that were assigned to the aromatic rings of curcumin. In addition, photoacoustic spectroscopy and X-ray diffraction, with the disappearance of the band related to aromatic rings, by Gaussian fitting, and modifications in the spectral lines, respectively, also suggested complex formation. The possible complexation had an efficiency of 74% and increased the solubility of the pure colourant 31-fold. Curcumin-β-CD complex exhibited a sunlight stability 18% higher than the pure colourant. This material was stable to pH variations and storage at -15 and 4°C. With an isothermal heating at 100 and 150°C for 2h, the material exhibited a colour retention of approximately 99%. The application of curcumin-β-CD complex in vanilla ice creams intensified the colour of the products and produced a great sensorial acceptance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Play Complexity and Toy Engagement in Preschoolers with Autism Spectrum Disorder: Do Girls and Boys Differ?

Science.gov (United States)

Harrop, Clare; Green, Jonathan; Hudry, Kristelle

2017-01-01

While sex differences in play have been extensively observed in typical development, only a handful of studies have explored this phenomenon in depth with children with autism spectrum disorders. This study explored sex differences in play complexity and toy engagement within caregiver-child interaction samples for preschool-aged children (2-5…

Complex-Spectrum Magnetic Environment enhances and/or modifies Bioeffects of Hypokinetic Stress Condition: an Animal Study

Science.gov (United States)

Temuriantz, N. A.; Martinyuk, V. S.; Ptitsyna, N. G.; Villoresi, G.; Iucci, N.; Tyasto, M. I.; Dorman, L. I.

During last decades it was shown by many authors that ultra-low and extremely low frequency electric and magnetic fields ULF 0-10 Hz ELF 10-1000 Hz may produce biological effects and consequently may be a possible source for health problems Spaceflight electric and magnetic environments are characterized by complex combination of static and time-varying components in ULF-ELF range and by high variability The objective of this study was to investigate the possible influence of such magnetic fields on rats to understand the pathway regarding functional state of cardiovascular system Magnetic field MF pattern with variable complex spectra in 0-150 Hz frequency range was simulated using 3-axial Helmholtz coils and special computer-based equipment The effect of the real world MF exposure on rats was also tested in combination with hypokinetic stress condition which is typical for spaceflights It was revealed that variable complex-spectrum MF acts as a weak or moderate stress-like factor which amplifies and or modifies the functional shifts caused by other stress-factors The value and direction of the functional shifts caused by MF exposure significantly depend on gender individual-typological constitutional features and also on the physiological state norm stress of organism Our results support the idea that variable complex-spectrum MF action involves sympathetic activation overload in cholesterol transport in blood and also secretor activation of tissue basophyls mast cells that can influence the regional haemodynamics These

Formation of a superhigh energy electron spectrum in the Galaxy

International Nuclear Information System (INIS)

Agaronyan, F.A.; Ambartsumyan, A.S.

1985-01-01

The formation of superhigh energy electron spectrum in the disk of the galaxy and halo is considered. A different behaviour of the electron spectrum within the framework of capture models in disk or halo, in the energy region E> or approximately 10 5 GeV is revealed due to the account of relativistic corrections ir the energy losses of electrons during the inverse Compton scattering. A comparison with the existing experimental data is carried out

Preparation, characterization, and thermal stability of β-cyclodextrin/soybean lecithin inclusion complex.

Science.gov (United States)

Wang, Xinge; Luo, Zhigang; Xiao, Zhigang

2014-01-30

β-Cyclodextrin (β-CD), which is widely used to increase the stability, solubility, and bioavailability of guests, can form host-guest inclusion complexes with a wide variety of organic molecules. In this study the β-CD/soybean lecithin inclusion complex was prepared. The effect of reaction parameters such as reaction temperature, reaction time and the molar ratio of β-CD/soybean lecithin on inclusion ratio were studied. The inclusion ratio of the product prepared under the optimal conditions of β-CD/soybean lecithin molar ratio 2:1, reaction temperature 60°C reaction time 2h was 40.2%. The results of UV-vis, DSC, XRD and FT-IR spectrum indicated the formation of inclusion complex. The thermal stability experiment indicated that the thermal stability of soybean lecithin in inclusion complex was significantly improved compared with free soybean lecithin. Copyright © 2013 Elsevier Ltd. All rights reserved.

Using Photographs of Contrasting Contextual Complexity to Support Classroom Transitions for Children with Autism Spectrum Disorders

Science.gov (United States)

Siegel, Ellin B.; Lien, Susan E.

2015-01-01

A single-subject, alternating treatment study compared the impact of two types of photograph displays of contrasting contextual complexity. The study examined the impact of high-context and no-context photographs, displayed on an iPad, on the ability of three preschool children with autism spectrum disorder (ASD) to transition to play activities.…

Optical Response of Cu1-xZnxIr2S4 Due to Metal--Insulator Transition

International Nuclear Information System (INIS)

Chen, L.; Matsunami, M.; Nanba, T.; Cao, G.; Suzuki, H.; Isobe, M.; Matsumoto, T.

2003-01-01

The mother material CuIr 2 S 4 of the thiospinel system Cu 1-x Zn x Ir 2 S 4 undergoes a temperature-induced metal--insulator (Mi) transition. We report the temperature dependence of the optical reflection spectra of Cu 1-x Zn x Ir 2 S 4 (x ≤ 0.5) at the temperatures of 8-300 K in the energy regions of 0.005--30 eV in order to study the change in the electronic structure due to the Zn substitution for Cu. Zn substitution induced mainly the splitting of the hybridization band between the Ir-5d(t 2g ) and S-3 p states crossing the E F . Obtained optical conductivity (σ ) spectrum is discussed in relation to the change in the electronic structure close to the E F . (author)

Chapter 1.1 Crystallinity of Nanocellulose Materials by Near-IR FT-Raman Spectroscopy

Science.gov (United States)

Umesh P. Agarwal; Richard S. Reiner; Sally A. Ralph

2013-01-01

Considering that crystallinity is one of the important properties that influence the end use of cellulose nanomaterials, it is important that the former be measured accurately. Recently, a new method based on near-IR FTRaman spectroscopy was proposed to determine cellulose I crystallinity. It was reported that in the Raman spectrum of cellulose materials, the...

Elucidation of the electronic spectrum changes of KA-Al3+ complex by potentiometric titration, FTIR, 13C NMR and quantum mechanics

International Nuclear Information System (INIS)

Piantavini, Mário S.; Gonçalves, Alan G.; Trindade, Ângela C.L.B.; Noseda, Miguel D.; Mercê, Ana L.R.; Pontarolo, Roberto; Machado, Antonio E.H.

2017-01-01

Kojic acid (KA) is an organic acid widely used in pharmaceutical industry, mainly as a skin lightening agent. Based on the ability of KA to form complexes with ions, we found the most possible kind of complex formed with cation aluminum. KA-Al 3+ complex structures were studied using potentiometric and spectrophotometric (UV) titrations, FTIR and 13 C NMR. The electronic spectroscopy showed that the KA-Al 3+ complexes absorb at higher wavelengths (λ max = 305 nm) than do the non-complexed KA (λ max = 269 nm), confirming complexation. The IR spectra of KA complexed and not complexed allowed to correlate the changes in the absorption of enol and carbonyl groups in absence and presence of Al 3+ in aqueous solutions. The complexation suggested by the potentiometric titration and FTIR spectroscopy are in accordance with the data obtained from NMR results. Calculations based on quantum mechanics were utilized to understand the differences found in the non complexed and complexed KAH electronic spectra. (author)

Optimization of silicon waveguides for gas detection application at mid-IR wavelengths

Science.gov (United States)

Butt, M. A.; Kozlova, E. S.

2018-04-01

There are several trace gases such as N2O, CO, CO2, NO, H2O, NO2, NH3, CH4 etc. which have their absorption peaks in Mid-IR spectrum These gases strongly absorb in the mid-IR > 2.5 μm spectral region due to their fundamental rotational and vibrational transitions. In this work, we modelled and optimized three different kinds of waveguides such as rib, strip and slot based on silicon platform to obtain maximum evanescent field ratio. These waveguides are designed at 3.39 μm and 4.67 μm which correspond to the absorption line of methane (CH4) and carbon monoxide (CO) respectively.

DFT study of IR and Raman spectra of phosphotrihydrazone dendrimer with terminal phenolic groups

Science.gov (United States)

Furer, V. L.; Vandyukov, A. E.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

2017-09-01

FT Raman and infrared spectra of phosphotrihydrazone (S)P[N(CH3)Ndbnd CHsbnd C6H4sbnd OH]3 (G0) were recorded. This compound is a zero generation phosphorus dendrimer with terminal phenolic groups. Optimal geometry and vibrational frequencies were calculated for G0 using the density functional theory (DFT). The molecule studied has C3 symmetry. In the molecule G0, each sbnd C6H4sbnd CHdbnd Nsbnd N(CH3)sbnd P arm is flat. Optimized geometric parameters correspond to experimental data. The core of the dendrimer manifests itself as a band at 647 cm-1 in the Raman spectrum of G0 related to Pdbnd S stretching. Phenolic end functions exhibit a well-defined band at 3374 cm-1 in the experimental IR spectrum of G0. The observed frequency of the OH stretching vibrations of the phenolic groups is lower than the theoretical value due to the intermolecular Osbnd H⋯O hydrogen bond. This hydrogen bond is also responsible for the higher intensity of this band in the experimental IR spectrum compared with the theoretical value. DFT calculations suggest full assignment of normal modes. Global and local descriptors characterize the reactivity of the core and end groups.

High-definition Fourier Transform Infrared (FT-IR) Spectroscopic Imaging of Human Tissue Sections towards Improving Pathology

Science.gov (United States)

Nguyen, Peter L.; Davidson, Bennett; Akkina, Sanjeev; Guzman, Grace; Setty, Suman; Kajdacsy-Balla, Andre; Walsh, Michael J.

2015-01-01

High-definition Fourier Transform Infrared (FT-IR) spectroscopic imaging is an emerging approach to obtain detailed images that have associated biochemical information. FT-IR imaging of tissue is based on the principle that different regions of the mid-infrared are absorbed by different chemical bonds (e.g., C=O, C-H, N-H) within cells or tissue that can then be related to the presence and composition of biomolecules (e.g., lipids, DNA, glycogen, protein, collagen). In an FT-IR image, every pixel within the image comprises an entire Infrared (IR) spectrum that can give information on the biochemical status of the cells that can then be exploited for cell-type or disease-type classification. In this paper, we show: how to obtain IR images from human tissues using an FT-IR system, how to modify existing instrumentation to allow for high-definition imaging capabilities, and how to visualize FT-IR images. We then present some applications of FT-IR for pathology using the liver and kidney as examples. FT-IR imaging holds exciting applications in providing a novel route to obtain biochemical information from cells and tissue in an entirely label-free non-perturbing route towards giving new insight into biomolecular changes as part of disease processes. Additionally, this biochemical information can potentially allow for objective and automated analysis of certain aspects of disease diagnosis. PMID:25650759

The investigation of hydrogens bonds between sulphur-bearing heterocyclic and proton-donor compounds by IR absorption spectra

International Nuclear Information System (INIS)

Narziev, B.N.; Nurulloev, M.; Makhkambaev, D.

1982-01-01

In this article the results of intermolecular interaction study of sulfur-containing heterocyclic (thiophene, thiophane) and proton-donar (water, alcohol, carbonic acids, chlorophon) molecules for measuring of IR spectrum absorption of protondonar compounds in soluted shape are presented

The TApIR experiment. IR absorption spectra of liquid hydrogen isotopologues; Das TApIR Experiment IR-Absorptionsspektren fluessiger Wasserstoffisotopologe

Energy Technology Data Exchange (ETDEWEB)

Groessle, Robin

2015-11-27

The scope of the thesis is the infrared absorption spectroscopy of liquid hydrogen isotopologues with the tritium absorption infrared spectroscopy (TApIR) experiment at the tritium laboratory Karlsruhe (TLK). The calibration process from the sample preparation to the reference measurements are described. A further issue is the classical evaluation of FTIR absorption spectra and the extension using the rolling circle filter (RCF) including the effects on statistical and systematical errors. The impact of thermal and nuclear spin temperature on the IR absorption spectra is discussed. An empirical based modeling for the IR absorption spectra of liquid hydrogen isotopologues is performed.

Vibrational spectroscopy of bare and solvated ionic complexes of biological relevance

NARCIS (Netherlands)

Polfer, N. C.; Oomens, J.

2009-01-01

The low density of ions in mass spectrometers generally precludes direct infrared (IR) absorption measurements. The IR spectrum of an ion can nonetheless be obtained by inducing photodissociation of the ion using a high-intensity tunable laser The emergence of free electron lasers (FELs) and recent

Photoinduced charge transfer in a transition metal complex investigated by time-resolved X-ray absorption fine structure spectroscopy. Setup and experiment

International Nuclear Information System (INIS)

Goeries, Dennis

2015-02-01

In the framework of this thesis the development of a time-resolved X-ray absorption spectroscopy experiment and its application to fac-Ir(ppy) 3 is described. Such experiments require a very stable setup in terms of spatial and temporal accuracy. Therefore, the stability properties of the present installation were investigated in detail and continuously improved, in particular the synchronization of the ultrashort pulse laser system to the storage ring as well as the spatial stability of both X-ray and laser beam. Experiments utilizing the laser pump and X-ray probe configuration were applied on the green phosphorescence emitter complex fac-Ir(ppy) 3 dissolved in dimethyl sulfoxide. Structural and electronic changes were triggered by photoexcitation of the metal-to-ligand charge transfer band with ultrashort laser pulses at a wavelength of 343 nm. The excited triplet state spectrum was extracted from the measured pump-probe X-ray absorption spectrum using an ionic approximation. The results con rm the anticipated metal-to-ligand charge transfer as shown by an ionization potential shift of the iridium atom. The symmetry of the complex was found to be pseudo-octahedral. This allowed the first experimental determination of the bond length of fac-Ir(ppy) 3 in an octahedral approximation and revealed a decrease of bond length of the first coordination shell in the triplet state. The first and second-order decay kinetics of the triplet state were investigated in a combination of X-ray and laser based experiments and revealed self-quenching as well as triplet-triplet annihilation rate constants.

Tarptautinio turizmo raida ir vystymo prognozės Lietuvoje ir Lenkijoje

OpenAIRE

Veličkaitė, Dalia

2009-01-01

Išanalizuota ir įvertinta Lietuvos ir Lenkijos atvykstamojo turizmo raida 2000- 2007m., užsienio turistų srautai, apgyvendinimo paslaugų paklausa, turistų tikslai ir kelionių transporto pasirinkimas, turistų išlaidos ir šalių turizmo pajamos, iškeltos atvykstamojo turizmo problemos bei pateikti jų sprendimo siūlymai.paskutinėje darbo dalyje buvo atliktos 2008- 2015metų Lietuvos ir Lenkijos turizmo raidos prognozės. In the final master work Lithuanian and Poland arriving tourism development...

Complete titanium substitution by boron in a tetragonal prism: exploring the complex boride series Ti(3-x)Ru(5-y)Ir(y)B(2+x) (0 ≤ x ≤ 1 and 1 theory.

Science.gov (United States)

Fokwa, Boniface P T; Hermus, Martin

2011-04-18

Polycrystalline samples and single crystals of four members of the new complex boride series Ti(3-x)Ru(5-y)Ir(y)B(2+x) (0 ≤ x ≤ 1 and 1 X-ray diffraction as well as energy- and wavelength-dispersive X-ray spectroscopy analyses. They crystallize with the tetragonal Ti(3)Co(5)B(2) structure type in space group P4/mbm (No. 127). Tetragonal prisms of Ru/Ir atoms are filled with titanium in the boron-poorest phase (Ti(3)Ru(2.9)Ir(2.1)B(2)). Gradual substitution of titanium by boron then results in the successive filling of this site by a Ti/B mixture en route to the complete boron occupation, leading to the boron-richest phase (Ti(2)Ru(2.8)Ir(2.2)B(3)). Furthermore, both ruthenium and iridium share two sites in these structures, but a clear Ru/Ir site preference is found. First-principles density functional theory calculations (Vienna ab initio simulation package) on appropriate structural models (using a supercell approach) have provided more evidence on the stability of the boron-richest and -poorest phases, and the calculated lattice parameters corroborate very well with the experimentally found ones. Linear muffin-tin orbital atomic sphere approximation calculations further supported these findings through crystal orbital Hamilton population bonding analyses, which also show that the Ru/Ir-B and Ru/Ir-Ti heteroatomic interactions are mainly responsible for the structural stability of these compounds. Furthermore, some stable and unstable phases of this complex series could be predicted using the rigid-band model. According to the density of states analyses, all phases should be metallic conductors, as was expected from these metal-rich borides.

Effect of source encapsulation on the energy spectra of sup 192 Ir and sup 137 Cs seed sources

Energy Technology Data Exchange (ETDEWEB)

Thomason, C [Wisconsin Univ., Madison, WI (USA). Dept. of Medical Physics; Mackie, T R [Wisconsin Univ., Madison, WI (USA). Dept. of Medical Physics Wisconsin Univ., Madison, WI (USA). Dept. of Human Oncology; Lindstrom, M J [Wisconsin Univ., Madison, WI (USA). Biostatistics Center

1991-04-01

The effect of source encapsulation on the energy spectra of {sup 192}Ir and {sup 137}Cs seed sources, both with stainless steel and with platinum encapsulation, was determined from results of Monte Carlo simulation. The fractional scatter dose around these sources has also been determined from Monte Carlo simulation. The platinum-encapsulated {sup 192}Ir source exhibited greater attenuation of the primary spectrum, as expected, and, consistent with this greater attenuation, exhibited more scattered radiation. Significantly less scatter was seen with the {sup 137}Cs source than with either {sup 192}Ir source, as is consistent with the higher-energy photons from {sup 137}Cs. (author).

Mid IR-fiber spectroscopy in the 2-17μm range

Science.gov (United States)

Artyushenko, Viatcheslav G.; Bocharnikov, A.; Colquhoun, Gary; Leach, Clive A.; Lobachov, Vladimir; Pirogova, Lyudmila; Sakharova, Tatjana; Savitskij, Dmitrij; Ezhevskaya, Tatjana; Bublikov, Alexandr

2007-10-01

The latest development in IR-fibre optics enables us to expand the spectral range of process spectroscopy from 2μm out to 17μm (5000 to 600cm-1) i.e. into the most informative "finger-print" part of the spectrum. Mid-IR wavelength ranges from 2 to 6-10μm may be covered by Chalcogenide IR-glass CIR-fibres while Polycrystalline PIR-fibres made of Silver Halides solid solutions transmit 4-17 μm wavelength radiation. PIR-fibre immersion ATR probes and Transmission/Reflection probes had been manufactured and successfully tested with different FTIR spectrometers in the field of remote spectroscopy for forensic substances identification, chemical reaction control, and monitoring of exhaust or exhalation gases. Using these techniques no sample preparation is necessary for fibre probes to measure evanescent, reflection and transmission spectra, in situ and in real time. QCL spectrometer may be used as a portable device for multispectral gas analysis at 1ppb level of detectivity for various applications in environmental pollution monitoring.

Optical properties of reduced graphene oxide and CuFe2O4 composites in the IR region

Science.gov (United States)

Ma, De-yue; Li, Xiao-xia; Guo, Yu-xiang; Zeng, Yu-run

2018-01-01

The complex refractive index of reduced graphene oxide and CuFe2O4 composites prepared by hydrothermal method was calculated using infrared Micro-reflective spectra and K-K relation, and the calculation errors were analyzed according to its IR transmission and spectral reflectivity calculated by Fresnel formula. And then normal emissivity of the composite in IR atmospheric window was calculated by means of Fresnel formula and modified refraction angle formula. The calculation accuracy was verified by comparing measured normal total emissivity with the calculated one. The results show that complex refractive index and normal emissivity calculated by the formulas have a high accuracy. It has been found that the composite has a good absorption and radiation characteristics in IR atmospheric window and a strong scattering ability in middle IR region by analyzing its extinction, absorption and radiation properties in IR region. Therefore, it may be used as IR absorption, extinction and radiation materials in some special fields.

Gas-phase infrared spectrum of the anionic GFP-chromophore

NARCIS (Netherlands)

Almasian, M.; Grzetic, J.; G. Berden,; Bakker, B.; Buma, W. J.; Oomens, J.

2012-01-01

The gas-phase IR spectrum of the anionic chromophore of the green fluorescent protein (p-hydroxy-benzylidene-2,3-dimethylimidazolidinone, HBDI) is recorded in the 800–1800 cm−1 frequency range using the free electron laser FELIX in combination with an electrospray ionization (ESI) Fourier

Electronic structure, local magnetism, and spin-orbit effects of Ir(IV)-, Ir(V)-, and Ir(VI)-based compounds

Energy Technology Data Exchange (ETDEWEB)

Laguna-Marco, M. A.; Kayser, P.; Alonso, J. A.; Martínez-Lope, M. J.; van Veenendaal, M.; Choi, Y.; Haskel, D.

2015-06-01

Element- and orbital-selective x-ray absorption and magnetic circular dichroism measurements are carried out to probe the electronic structure and magnetism of Ir 5d electronic states in double perovskite Sr2MIrO6 (M = Mg, Ca, Sc, Ti, Ni, Fe, Zn, In) and La2NiIrO6 compounds. All the studied systems present a significant influence of spin-orbit interactions in the electronic ground state. In addition, we find that the Ir 5d local magnetic moment shows different character depending on the oxidation state despite the net magnetization being similar for all the compounds. Ir carries an orbital contribution comparable to the spin contribution for Ir4+ (5d(5)) and Ir5+ (5d(4)) oxides, whereas the orbital contribution is quenched for Ir6+ (5d(3)) samples. Incorporation of a magnetic 3d atom allows getting insight into the magnetic coupling between 5d and 3d transition metals. Together with previous susceptibility and neutron diffractionmeasurements, the results indicate that Ir carries a significant local magnetic moment even in samples without a 3d metal. The size of the (small) net magnetization of these compounds is a result of predominant antiferromagnetic interactions between local moments coupled with structural details of each perovskite structure

PKCδ-mediated IRS-1 Ser24 phosphorylation negatively regulates IRS-1 function

International Nuclear Information System (INIS)

Greene, Michael W.; Ruhoff, Mary S.; Roth, Richard A.; Kim, Jeong-a; Quon, Michael J.; Krause, Jean A.

2006-01-01

The IRS-1 PH and PTB domains are essential for insulin-stimulated IRS-1 Tyr phosphorylation and insulin signaling, while Ser/Thr phosphorylation of IRS-1 disrupts these signaling events. To investigate consensus PKC phosphorylation sites in the PH-PTB domains of human IRS-1, we changed Ser24, Ser58, and Thr191 to Ala (3A) or Glu (3E), to block or mimic phosphorylation, respectively. The 3A mutant abrogated the inhibitory effect of PKCδ on insulin-stimulated IRS-1 Tyr phosphorylation, while reductions in insulin-stimulated IRS-1 Tyr phosphorylation, cellular proliferation, and Akt activation were observed with the 3E mutant. When single Glu mutants were tested, the Ser24 to Glu mutant had the greatest inhibitory effect on insulin-stimulated IRS-1 Tyr phosphorylation. PKCδ-mediated IRS-1 Ser24 phosphorylation was confirmed in cells with PKCδ catalytic domain mutants and by an RNAi method. Mechanistic studies revealed that IRS-1 with Ala and Glu point mutations at Ser24 impaired phosphatidylinositol-4,5-bisphosphate binding. In summary, our data are consistent with the hypothesis that Ser24 is a negative regulatory phosphorylation site in IRS-1

In vivo dosimetry thermoluminescence dosimeters during brachytherapy with a 370 GBq 192Ir source

International Nuclear Information System (INIS)

Cuepers, S.; Piessens, M.; Verbeke, L.; Roelstraete, A.

1995-01-01

When using LiF thermoluminescence dosimeters in brachytherapy, we have to take into account the properties of a high dose rate 192 Ir source (energy spectrum ranging form 9 to 885 keV, steep dose gradient in the vicinity of the source) and these of the dosimeters themselves (supralinearity, reproducibility, size). All these characteristics combine into a set of correction factors which have been determined during in phantom measurements. These results have then been used to measure the dose delivered to organs at risk (e.g. rectum, bladder, etc.) during high dose rate brachytherapy with a 370 GBq 192 Ir source for patients with gynaecological tumors

Theoretical study on the antitumor properties of Ru(II) complexes containing 2-pyridyl, 2-pyridine-4-carboxylic acid ligands

Science.gov (United States)

Erkan kariper, Sultan; Sayin, Koray; Karakaş, Duran

2017-12-01

[Ru(bipy)2(CppH)]2+(1), [Ru(bipy)2(Cpp-NH-Hex-COOH)]2+(2), [Ru(dppz)2(CppH)]2+(3) and [Ru(dppz)2(Cpp-NH-Hex-COOH)]2+(4) were calculated by Hartree-Fock (HF), Density Functional Theory (DFT) hybrid B3LYP and Moller-Plesset Perturbation (MPn n = 2,3) theory method and CEP-4G, CEP-31G, CEP-121G, LANL2DZ, LANL2MB, SDD basic sets and a mixed basic set with the keyword GEN in gas phase and water. Structure parameters obtained from optimized structures were compared with experimental parameters. M062X/(6-31G(d))(CEP-4G) level was taken into account for the most appropriate calculation level. IR, UV-VIS and NMR spectrums were examined for structural characterization. The optimal structure was identified via structure parameters, IR, UV-VIS and NMR spectrums. For the most compatible structure, the highest molecular orbital energy (EHOMO) which one of the most effective chemical determiners on the antitumor activity of the complexes, the lowest molecular orbital energy (ELUMO), LUMO-HOMO energy gap, hardness (η), softness (σ), electronegativity (χ), chemical potential (μ), electrophilicity index (ω), molar volume (V), dipole moment (DM), total negative charge (TNC), enthalpy (H), entropy (S) and total energy (E) were calculated. The causes of anticancer activity of the complexes have been studied.

IRS-1 acts as an endocytic regulator of IGF-I receptor to facilitate sustained IGF signaling.

Science.gov (United States)

Yoneyama, Yosuke; Lanzerstorfer, Peter; Niwa, Hideaki; Umehara, Takashi; Shibano, Takashi; Yokoyama, Shigeyuki; Chida, Kazuhiro; Weghuber, Julian; Hakuno, Fumihiko; Takahashi, Shin-Ichiro

2018-04-11

Insulin-like growth factor-I receptor (IGF-IR) preferentially regulates the long-term IGF activities including growth and metabolism. Kinetics of ligand-dependent IGF-IR endocytosis determines how IGF induces such downstream signaling outputs. Here, we find that the insulin receptor substrate (IRS)-1 modulates how long ligand-activated IGF-IR remains at the cell surface before undergoing endocytosis in mammalian cells. IRS-1 interacts with the clathrin adaptor complex AP2. IRS-1, but not an AP2-binding-deficient mutant, delays AP2-mediated IGF-IR endocytosis after the ligand stimulation. Mechanistically, IRS-1 inhibits the recruitment of IGF-IR into clathrin-coated structures; for this reason, IGF-IR avoids rapid endocytosis and prolongs its activity on the cell surface. Accelerating IGF-IR endocytosis via IRS-1 depletion induces the shift from sustained to transient Akt activation and augments FoxO-mediated transcription. Our study establishes a new role for IRS-1 as an endocytic regulator of IGF-IR that ensures sustained IGF bioactivity, independent of its classic role as an adaptor in IGF-IR signaling. © 2018, Yoneyama et al.

Clouds on the hot Jupiter HD189733b: Constraints from the reflection spectrum

Energy Technology Data Exchange (ETDEWEB)

Barstow, J. K.; Aigrain, S.; Irwin, P. G. J.; Hackler, T.; Fletcher, L. N. [Department of Physics, University of Oxford, Oxford (United Kingdom); Lee, J. M. [Institute for Theoretical Physics, University of Zürich, CH-8057 Zürich (Switzerland); Gibson, N. P., E-mail: jo.barstow@astro.ox.ac.uk [European Southern Observatory, D-85748 Garching bei München (Germany)

2014-05-10

The hot Jupiter HD 189733b is probably the best studied of the known extrasolar planets, with published transit and eclipse spectra covering the near UV to mid-IR range. Recent work on the transmission spectrum has shown clear evidence for the presence of clouds in its atmosphere, which significantly increases the model atmosphere parameter space that must be explored in order to fully characterize this planet. In this work, we apply the NEMESIS atmospheric retrieval code to the recently published HST/STIS reflection spectrum, and also to the dayside thermal emission spectrum in light of new Spitzer/IRAC measurements, as well as our own re-analysis of the HST/NICMOS data. We first use the STIS data to place some constraints on the nature of clouds on HD 189733b and explore solution degeneracy between different cloud properties and the abundance of Na in the atmosphere; as already noted in previous work, absorption due to Na plays a significant role in determining the shape of the reflection spectrum. We then perform a new retrieval of the temperature profile and abundances of H{sub 2}O, CO{sub 2}, CO, and CH{sub 4} from the dayside thermal emission spectrum. Finally, we investigate the effect of including cloud in the model on this retrieval process. We find that the current quality of data does not warrant the extra complexity introduced by including cloud in the model; however, future data are likely to be of sufficient resolution and signal-to-noise that a more complete model, including scattering particles, will be required.

EFFECTS OF FATLIQURING PROCESS ON LEATHERS COLOURED WITH IR REFLECTIVE DYES AND PIGMENTS

Directory of Open Access Journals (Sweden)

MUTLU Mehmet Mete

2017-05-01

Full Text Available Black coloured materials and consumer goods are known to be heating up more, because they absorb sun radiation more than light colours. This heating is a problem for the users for black automotive or motorcycle leathers and also for dark shoes and boots which are exposed to sun heat. Human vision system can distinguish visible colours between the wavelengths of 390-700 nm. So reflecting the sun radiation in the infrared area of radiation spectrum higher than 700nm, is a solution for heating problem without affecting the visible colour. For this reason IR reflective dyes and pigments are designed. A leading Leather Chemical Company has developed an IR reflecting dyeing system for leather keeping the dark coloured leathers cooler under sun radiation. Additionally in theory, fat and water content of leather affects its heating properties. In this study, effect of natural, synthetic and waterproof fatliquoring systems on heating properties of leathers coloured with IR reflective dyes and pigments are investigated.

Autism Spectrum Disorders (ASD) and Diet

Science.gov (United States)

... Conditions Autism Autism Spectrum Disorders (ASD) and Diet Autism Spectrum Disorders (ASD) and Diet By Karen Ansel, MS, RDN, CDN Published April 2, 2018 nambitomo/iStock/Thinkstock Autism Spectrum Disorder, or ASD, is a complex developmental and neurological ...

The 3 micron spectrum of NGC 4565

International Nuclear Information System (INIS)

Adamson, A.J.; Whittet, D.C.B.

1990-01-01

Researchers spectrum of NGC 4565 is essentially featureless. The absence of the 3.0 micron feature (Tau 3.0 less than 0.05) implies that the extinction to the nucleus does not arise to a significant degree in molecular clouds. Researchers deduce Tau 3.0/A sub V less than 0.01, compared with approx. 0.022 for GC-IRS7. These results support the conclusion (McFadzean et al. 1989) that the 3.0 micron absorption in the GC-IR sources is due to the presence of ice in a (probably single) foreground molecular cloud. The 3.4 micron feature is also weak or absent in the researchers spectrum of NGC 4565 (Tau 3.4 less than or equal to 0.07), hence, Tau 3.4/A sub V less than or equal to 0.016, compared with approx. 0.008 towards GC-IRS7. The absence of the feature in NGC 4565 at the signal-to-noise level of the current observations is consistent with a probable moderate degree of extinction towards the nucleus. The observations of NGC 4565 provide a useful comparison for studies of dust in the Galaxy. Limits have been set on the strengths of the 3.0 and 3.4 micron features in NGC 4565. The absence of 3.0 micron absorption is significant, and supports the view that the feature at this wavelength in the Galactic Centre is due to water-ice absorption in a foreground molecular cloud. The non-detection of the 3.4 micron absorption is less surprising and provides indirect support for the association between this feature and the diffuse interstellar medium. The current spectrum probably represents the best that can be achieved with a single-detector instrument within reasonable integration times. It will clearly be of interest in the future to obtain spectra of higher signal-to-noise, as a positive detection of the 3.4 micron feature in an external galaxy, even at a low level, would be of considerable astrophysical significance

Complex autism spectrum disorder in a patient with a 17q12 microduplication.

Science.gov (United States)

Brandt, Tracy; Desai, Khyati; Grodberg, David; Mehta, Lakshmi; Cohen, Ninette; Tryfon, Ana; Kolevzon, Alexander; Soorya, Latha; Buxbaum, Joseph D; Edelmann, Lisa

2012-05-01

Autism spectrum disorders (ASDs) are phenotypically complex developmental neuropsychiatric disorders affecting approximately 0.6% of the population. About 30-70% of affected children are also considered to have intellectual disability (ID). The underlying genetic causes of ASDs are diverse with a defined etiology in 16-20%. Array comparative genomic hybridization (aCGH) has proven useful in identifying sub-microscopic chromosome aberrations in a subset of patients, some of which have been shown to be recurrent. One such aberration is the 1.4 Mb microdeletion at chromosome 17q12, which has been reported to be associated with renal disease, growth restriction, diabetes, cognitive impairment, seizures, and in some cases an ASD. Patients with the reciprocal chromosome 17q12 microduplication typically have also been identified with ID and in some cases seizures and behavioral abnormalities. Here we report a patient with a de novo, 1.4 Mb microduplication diagnosed with significant ID involving complex deficits and autism. To our knowledge, this is the first report of a patient with the 17q12 microduplication and a complex ASD phenotype. Copyright © 2012 Wiley Periodicals, Inc.

76 FR 57804 - Proposed Collection; Comment Request for the IRS Individual Taxpayer Burden Survey

Science.gov (United States)

2011-09-16

... received on or before November 15, 2011 to be assured of consideration. ADDRESSES: Direct all written... submit more than 140 million tax returns to the Internal Revenue Service (IRS). The IRS uses the... administer a tax system whose rules span thousands of pages. Managing such a complex and broad-based tax...

Organic and inorganic interpretations of the martian UV-IR reflectance spectrum

Energy Technology Data Exchange (ETDEWEB)

Pang, K D; Ajello, J M [Jet Propulsion Lab., Pasadena, CA (USA); Chun, S F.S. [California Univ., San Francisco (USA). School of Medicine; Nansheng, Z [Beijing Planetarium (China); Minji, L [Beijing Glass Institute (China)

1982-01-07

The Viking gas chromatography-mass spectrometer analysis of martian soil samples are discussed, in particular why no organic molecules were detected at the landing sites, whether the sterility of the two sites is representative of the entire planet and if there are locations on Mars more conducive to the formation and preservation of organics. The destruction of organic compounds has been simulated in Mars-like laboratory conditions and the possible planetwide destructive mechanism considered. The UV and IR reflectance spectra of Mars has been re-examined for any evidence of organic molecules and an upper limit on the organic carbon content of average martian soil has been set. The results reveal that the average martian soil is organic-poor, makes an unfavourable habitat for life forms based on carbon chemistry, and there is no reason to believe that organic molecules are preferentially preserved anywhere on the planet.

Organic and inorganic interpretations of the martian UV-IR reflectance spectrum

International Nuclear Information System (INIS)

Pang, K.D.; Ajello, J.M.; Chun, S.F.S.; Minji, L.

1982-01-01

The Viking gas chromatography-mass spectrometer analysis of martian soil samples are discussed, in particular why no organic molecules were detected at the landing sites, whether the sterility of the two sites is representative of the entire planet and if there are locations on Mars more conducive to the formation and preservation of organics. The destruction of organic compounds has been simulated in Mars-like laboratory conditions and the possible planetwide destructive mechanism considered. The UV and IR reflectance spectra of Mars has been re-examined for any evidence of organic molecules and an upper limit on the organic carbon content of average martian soil has been set. The results reveal that the average martian soil is organic-poor, makes an unfavourable habitat for life forms based on carbon chemistry, and there is no reason to believe that organic molecules are preferentially preserved anywhere on the planet. (U.K.)

Impulsive IR-multiphoton dissociation of acrolein: observation of non-statistical product vibrational excitation in CO ( v=1-12) by time resolved IR fluorescence spectroscopy

Science.gov (United States)

Chowdhury, P. K.

2000-10-01

On IR-multiphoton excitation, vibrationally highly excited acrolein molecules undergo concerted dissociation generating CO and ethylene. The vibrationally excited products, CO and ethylene, are detected immediately following the CO 2 laser pulse by observing IR fluorescence at 4.7 and 3.2 μm, respectively. The nascent CO is formed with significant vibrational excitation, with a Boltzmann population distribution for v=1-12 levels corresponding to T v=12 950±50 K. The average vibrational energy in the product CO is found to be 26 kcal mol -1, in contrast to its statistical share of 5 kcal mol -1, available from the product energy distribution. The nascent vibrationally excited ethylene either dissociates by absorbing further infrared laser photons from the tail of the CO 2 laser pulse or relaxes by collisional deactivation. Ethylene IR-fluorescence excitation spectrum showed a structure in the quasi-continuum, with a facile resonance at 10.53 μm corresponding to the 10P(14) CO 2 laser line, which explains the higher acetylene yield observed at a higher pressure. A hydrogen atom transfer mechanism followed by C-C impulsive break in the acrolein transition state may be responsible for such non-statistical product energy distribution.

UV/IR mixing and the Goldstone theorem in noncommutative field theory

International Nuclear Information System (INIS)

Ruiz Ruiz, F.

2002-01-01

Noncommutative IR singularities and UV/IR mixing in relation with the Goldstone theorem for complex scalar field theory are investigated. The classical model has two coupling constants, λ 1 and λ 2 , associated to the two noncommutative extensions phi*starphistarphi* starphi and phistarphi*starphistarphi of the interaction term vertical bar phi vertical bar 4 on commutative spacetime. It is shown that the symmetric phase is one-loop renormalizable for all λ 1 and λ 2 compatible with perturbation theory, whereas the broken phase is proved to exist at one loop only if λ 2 =0, a condition required by the Ward identities for global U(1) invariance. Explicit expressions for the noncommutative IR singularities in the 1PI Green functions of both phases are given. They show that UV/IR duality does not hold for any of the phases and that the broken phase is free of quadratic noncommutative IR singularities. More remarkably, the pion selfenergy does not have noncommutative IR singularities at all, which proves essential to formulate the Goldstone theorem at one loop for all values of the spacetime noncommutativity parameter θ

Synthesis, structural, antibacterial and spectral studies of Co (II) complexes with salicylaldehyde and p-chloro-benzaldehyde 4-phenyl thiosemicarbazone

International Nuclear Information System (INIS)

Nur Nadia Dzulkifli; Yang Farina; Ibrahim Baba; Nazlina Ibrahim

2012-01-01

The Co(II) complexes derived from salicylaldehyde 4-phenyl thiosemicarbazone; SaOHtsc, p-chlorobenzaldehyde 4-phenyl thiosemicarbazone; ph-HClbtsc is reported and characterized based on elemental analysis, IR, magnetic susceptibility measurement, 1 H and 13 C NMR spectra. The Co(II) complexes have the molecular formula CoL 2 where the ligand corresponding to SaOHtsc and ph-HClbtsc. The elemental analysis for the ligands and complexes were in a good agreement with the theoretical values. The ligands coordinate to metal ions in different ways which is through mono negative bidentate or di negative tridentate. The magnetic susceptibility measurements showed that the CoL 2 complexes with ligand SaOHtsc are diamagnetic thus making this complexes suitable for NMR studies. The signals at the 10.04 ppm were assigned to N 2 H in the 1 H-NMR spectra of the free ligands was absent in the spectra of the complexes due to the deprotonation of the N 2 H and coordination to the metal centres. The absence of the band in IR spectrum which is assigned to v(N 2 -H) in the spectra of CoL 2 complexes is due to the deprotonation of the ligands upon complexation through azomethine nitrogen and thionic sulphur atom to metal ion. The thiosemicarbazones and its Co(II) complexes showed moderate inhibitory against bacteria Bacillus Subtilis, Staphylococcus Epidermis, Escherichia Coli and Proteus Mirabilis in 10 μg/ disc. (author)

Analysis of the development of missile-borne IR imaging detecting technologies

Science.gov (United States)

Fan, Jinxiang; Wang, Feng

2017-10-01

Today's infrared imaging guiding missiles are facing many challenges. With the development of targets' stealth, new-style IR countermeasures and penetrating technologies as well as the complexity of the operational environments, infrared imaging guiding missiles must meet the higher requirements of efficient target detection, capability of anti-interference and anti-jamming and the operational adaptability in complex, dynamic operating environments. Missileborne infrared imaging detecting systems are constrained by practical considerations like cost, size, weight and power (SWaP), and lifecycle requirements. Future-generation infrared imaging guiding missiles need to be resilient to changing operating environments and capable of doing more with fewer resources. Advanced IR imaging detecting and information exploring technologies are the key technologies that affect the future direction of IR imaging guidance missiles. Infrared imaging detecting and information exploring technologies research will support the development of more robust and efficient missile-borne infrared imaging detecting systems. Novelty IR imaging technologies, such as Infrared adaptive spectral imaging, are the key to effectively detect, recognize and track target under the complicated operating and countermeasures environments. Innovative information exploring techniques for the information of target, background and countermeasures provided by the detection system is the base for missile to recognize target and counter interference, jamming and countermeasure. Modular hardware and software development is the enabler for implementing multi-purpose, multi-function solutions. Uncooled IRFPA detectors and High-operating temperature IRFPA detectors as well as commercial-off-the-shelf (COTS) technology will support the implementing of low-cost infrared imaging guiding missiles. In this paper, the current status and features of missile-borne IR imaging detecting technologies are summarized. The key

New investigations of the guanine trichloro cuprate(II) complex crystal

Science.gov (United States)

Fabijanić, Ivana; Matković-Čalogović, Dubravka; Pilepić, Viktor; Ivanišević, Irena; Mohaček-Grošev, Vlasta; Sanković, Krešimir

2017-01-01

Crystals of the guanine trichloro cuprate(II) complex, (HGua)2[Cu2Cl6]·2H2O (HGua = protonated guanine), were prepared and analysed by spectroscopic (IR, Raman) and computational methods. A new single-crystal X-ray diffraction analysis was conducted to obtain data with lower standard uncertainties than those in the previously published structure. Raman and IR spectroscopy and quantum-mechanical analysis gave us new insight into the vibrational states of the (HGua)2[Cu2Cl6]·2H2O crystal. The vibrational spectra of the crystal were assigned by performing a normal coordinate analysis for a free dimer with a centre of inversion as the only symmetry element. The stretching vibration observed at 279 cm-1 in the infrared spectrum corresponds to the N-Cu bond. The noncovalent interaction (NCI) plots and quantum theory of atoms in molecules (QTAIM) analysis of the electron density obtained from periodic DFT calculations elucidated the interactions that exist within the crystal structure. Closed-shell ionic attractions, as well as weak and medium strength hydrogen bonds, prevailed in the crystal packing.

Combined two-photon excitation and d → f energy-transfer in Ir/lanthanide dyads with time-gated selection from a two-component emission spectrum.

Science.gov (United States)

Edkins, Robert M; Sykes, Daniel; Beeby, Andrew; Ward, Michael D

2012-10-14

In a pair of Ir/Eu and Ir/Tb dyads, two-photon excitation of the Ir-phenylpyridine chromophore at 780 nm is followed by partial d → f energy-transfer to give a combination of short-lived Ir-based (blue) and long-lived lanthanide-based (red or green) emission; these components can be selected separately by time-gated detection.

In vivo dosimetry thermoluminescence dosimeters during brachytherapy with a 370 GBq {sup 192}Ir source

Energy Technology Data Exchange (ETDEWEB)

Cuepers, S; Piessens, M; Verbeke, L; Roelstraete, A [Onze-Lieve-Vrouw Hospitaal, Aalst (Belgium). Dept. of Radiotherapy and Oncology

1995-12-01

When using LiF thermoluminescence dosimeters in brachytherapy, we have to take into account the properties of a high dose rate {sup 192}Ir source (energy spectrum ranging form 9 to 885 keV, steep dose gradient in the vicinity of the source) and these of the dosimeters themselves (supralinearity, reproducibility, size). All these characteristics combine into a set of correction factors which have been determined during in phantom measurements. These results have then been used to measure the dose delivered to organs at risk (e.g. rectum, bladder, etc.) during high dose rate brachytherapy with a 370 GBq {sup 192}Ir source for patients with gynaecological tumors.

Equidistance of the complex two-dimensional anharmonic oscillator spectrum: the exact solution

International Nuclear Information System (INIS)

Cannata, F; Ioffe, M V; Nishnianidze, D N

2012-01-01

We study a class of quantum two-dimensional models with complex potentials of a specific form. They can be considered as the generalization of a recently studied model with quadratic interaction not amenable to the conventional separation of variables. In the present case, the property of shape invariance provides the equidistant form of the spectrum and the algorithm to construct eigenfunctions analytically. It is shown that the Hamiltonian is non-diagonalizable, and the resolution of identity must also include the corresponding associated functions. In the specific case of anharmonic second plus fourth-order interaction, expressions for the wavefunctions and associated functions are constructed explicitly for the lowest levels, and the recursive algorithm to produce higher level wavefunctions is given. (paper)

High-pressure versus isoelectronic doping effect on the honeycomb iridate Na2IrO3

Science.gov (United States)

Hermann, V.; Ebad-Allah, J.; Freund, F.; Pietsch, I. M.; Jesche, A.; Tsirlin, A. A.; Deisenhofer, J.; Hanfland, M.; Gegenwart, P.; Kuntscher, C. A.

2017-11-01

We study the effect of isoelectronic doping and external pressure in tuning the ground state of the honeycomb iridate Na2IrO3 by combining optical spectroscopy with synchrotron x-ray diffraction measurements on single crystals. The obtained optical conductivity of Na2IrO3 is discussed in terms of a Mott-insulating picture versus the formation of quasimolecular orbitals and in terms of Kitaev interactions. With increasing Li content x , (Na1 -xLix )2IrO3 moves deeper into the Mott-insulating regime, and there are indications that up to a doping level of 24% the compound comes closer to the Kitaev limit. The optical conductivity spectrum of single-crystalline α -Li2IrO3 does not follow the trends observed for the series up to x =0.24 . There are strong indications that α -Li2IrO3 is not as close to the Kitaev limit as Na2IrO3 and lies closer to the quasimolecular orbital picture instead. Except for the pressure-induced hardening of the phonon modes, the optical properties of Na2IrO3 seem to be robust against external pressure. Possible explanations of the unexpected evolution of the optical conductivity with isolectronic doping and the drastic change between x =0.24 and x =1 are given by comparing the pressure-induced changes of lattice parameters and the optical conductivity with the corresponding changes induced by doping.

Magnetic Excitations across the Metal-Insulator Transition in the Pyrochlore Iridate Eu2Ir2O7

Science.gov (United States)

Chun, Sae Hwan; Yuan, Bo; Casa, Diego; Kim, Jungho; Kim, Chang-Yong; Tian, Zhaoming; Qiu, Yang; Nakatsuji, Satoru; Kim, Young-June

2018-04-01

We report a resonant inelastic x-ray scattering study of the magnetic excitation spectrum in a highly insulating Eu2 Ir2 O7 single crystal that exhibits a metal-insulator transition at TMI=111 (7 ) K . A propagating magnon mode with a 20 meV bandwidth and a 28 meV magnon gap is found in the excitation spectrum at 7 K, which is expected in the all-in-all-out magnetically ordered state. This magnetic excitation exhibits substantial softening as the temperature is raised towards TMI and turns into a highly damped excitation in the paramagnetic phase. Remarkably, the softening occurs throughout the whole Brillouin zone including the zone boundary. This observation is inconsistent with the magnon renormalization expected in a local moment system and indicates that the strength of the electron correlation in Eu2 Ir2 O7 is only moderate, so that electron itinerancy should be taken into account in describing its magnetism.

MicrOmega IR: a new infrared hyperspectral imaging microscope or in situ analysis

Science.gov (United States)

Vaitua, Leroi; Bibring, Jean-Pierre; Berthé, Michel

2017-11-01

MicrOmega IR is an ultra miniaturized Near Infrared hyperspectral microscope for in situ analysis of samples. It is designed to be implemented on board space planetary vehicles (lander and/or rovers). It acquires images of samples typically some 5 mm in width with a spatial sampling of 20 μm. On each pixel, MicrOmega acquires the spectrum in the spectral range 0.9 - 2.6 μm, with a possibility to extend the sensibility up to 4 μm. The spectrum will be measured in up to 300 contiguous spectral channels (600 in the extended range): given the diagnostic spectral features present in this domain, it provides the composition of each spatially resolved constituent. MicrOmega has thus the potential to identify: minerals, such as pyroxene and olivine, ferric oxides, hydrated phases such as phyllosilicates, sulfates and carbonates, ices and organics. The composition of the various phases within a given sample is a critical record of its formation and evolution. Coupled to the mapping information, it provides unique clues to describe the history of the parent body. In particular, the capability to identify hydrated grains and to characterize their adjacent phases has a huge potential in the search for potential bio-relics in Martian samples. This purely non destructive characterization enables further analyses (e.g. through mass spectrometry) to be performed, and/or to contribute to sample selection to return to Earth. MicrOmega IR is coupled to a visible microscope: MicrOmega VIS. Thus, the MicrOmega instrument is developed by an international consortium: IAS (Orsay, France), LESIA (Meudon, France), CBM (Orléans, France), University Of Bern (Bern, Switzerland), IKI (Moscow, Russia). This instrument (MicrOmega IR, MicrOmega VIS and the electronics) is selected for the ESA Exomars mission (launch scheduled for 2013). MicrOmega IR will be used in a reduced spectral range (0.9 - 2.6 μm), due to power, mass and thermal constraints: however, most minerals and other

Measurement of the Shape of the Optical-IR Spectrum of Prompt Emission from Gamma-Ray Bursts

Science.gov (United States)

Grossan, Bruce; Kistaubayev, M.; Smoot, G.; Scherr, L.

2017-06-01

While the afterglow phase of gamma-ray bursts (GRBs) has been extensively measured, detections of prompt emission (i.e. during bright X-gamma emission) are more limited. Some prompt optical measurements are regularly made, but these are typically in a single wide band, with limited time resolution, and no measurement of spectral shape. Some models predict a synchrotron self-absorption spectral break somewhere in the IR-optical region. Measurement of the absorption frequency would give extensive information on each burst, including the electron Lorentz factor, the radius of emission, and more (Shen & Zhang 2008). Thus far the best prompt observations have been explained invoking a variety of models, but often with a non-unique interpretation. To understand this apparently heterogeneous behavior, and to reduce the number of possible models, it is critical to add data on the optical - IR spectral shape.Long GRB prompt X-gamma emission typically lasts ~40-80 s. The Swift BAT instrument rapidly measures GRB positions to within a few arc minutes and communicates them via the internet within a few seconds. We have measured the time for a fast-moving D=700 mm telescope to point and settle to be less than 9 s anywhere on the observable sky. Therefore, the majority of prompt optical-IR emission can be measured responding to BAT positions with this telescope. In this presentation, we describe our observing and science programs, and give our design for the Burst Simultaneous Three-channel Instrument (BSTI), which uses dichroics to send eparate bands to 3 cameras. Two EMCCD cameras, give high-time resolution in B and V; a third camera with a HgCdTe sensor covers H band, allowing us to study extinguished bursts. For a total exposure time of 10 s, we find a 5 sigma sensitivity of 21.3 and 20.3 mag in B and R for 1" seeing and Kitt Peak sky brightness, much fainter than typical previous prompt detections. We estimate 5 sigma H-band sensitivity for an IR optimized telescope to be

Synthesis, spectral characterization and structural studies of a novel O, N, O donor semicarbazone and its binuclear copper complex with hydrogen bond stabilized lattice

Science.gov (United States)

Layana, S. R.; Saritha, S. R.; Anitha, L.; Sithambaresan, M.; Sudarsanakumar, M. R.; Suma, S.

2018-04-01

A novel O,N,O donor salicylaldehyde-N4-phenylsemicarbazone, (H2L) has been synthesized and physicochemically characterized. Detailed structural studies of H2L using single crystal X-ray diffraction technique reveals the existence of intra and inter molecular hydrogen bonding interactions, which provide extra stability to the molecule. We have successfully synthesized a binuclear copper(II) complex, [Cu2(HL)2(NO3)(H2O)2]NO3 with phenoxy bridging between the two copper centers. The complex was characterized by elemental analysis, magnetic susceptibility and conductivity measurements, FT-IR, UV-Visible, mass and EPR spectral methods. The grown crystals of the copper complex were employed for the single crystal X-ray diffraction studies. The complex possesses geometrically different metal centers, in which the ligand coordinates through ketoamide oxygen, azomethine nitrogen and deprotonated phenoxy oxygen. The extensive intermolecular hydrogen bonding interactions of the coordinated and the lattice nitrate groups interconnect the complex units to form a 2D supramolecular assembly. The ESI mass spectrum substantiates the existence of 1:1 complex. The g values obtained from the EPR spectrum in frozen DMF suggest dx2 -y2 ground state for the unpaired electron.

Adding a dimension to the infrared spectra of interfaces: 2D SFG spectroscopy via mid-IR pulse shaping

Science.gov (United States)

Zanni, Martin

2012-02-01

Sum-frequency generation spectroscopy provides an infrared spectrum of interfaces and thus has widespread use in the materials and chemical sciences. In this presentation, I will present our recent work in developing a 2D pulse sequence to generate 2D SFG spectra of interfaces, in analogy to 2D infrared spectra used to measure bulk species. To develop this spectroscopy, we have utilized many of the tricks-of-the-trade developed in the 2D IR and 2D Vis communities in the last decade, including mid-IR pulse shaping. With mid-IR pulse shaping, the 2D pulse sequence is manipulated by computer programming in the desired frequency resolution, rotating frame, and signal pathway. We believe that 2D SFG will become an important tool in the interfacial sciences in an analogous way that 2D IR is now being used in many disciplines.

New horizons for Supercontinuum light sources: from UV to mid-IR

DEFF Research Database (Denmark)

Thomsen, Carsten L.; Nielsen, Frederik Donbæk; Johansen, Jeppe

2013-01-01

Commercially available supercontinuum sources continue to experience a strong growth in a wide range of industrial and scientific applications. In addition, there is a significant research effort focused on extending the wavelength coverage both towards UV and Mid-IR. Broadband sources covering...... and novel pumping schemes, whereas shifting the spectrum further towards the UV has been based on sophisticated microstructure fiber designs. Here we present our latest developments in tailoring the power and spectral coverage of spatially coherent broadband supercontinuum sources....

Preparation and Characterization of cis- and trans-[Ir(tn)2Cl2]CF3SO3 and of [Ir(tn)3]Cl3 (tn=propane-1,3-diamine)

DEFF Research Database (Denmark)

Brorson, Michael; Galsbøl, Frode; Simonsen, Kim

1998-01-01

for the preparation of [Rh(tn)3]Cl3 in quantitative yield from Rh(thtp)3Cl3 is also given. The complexes were characterized by 1H and 13C NMR and by UV/VIS spectroscopy. The conformation of the six-membered chelate rings of [Ir(tn)3]3+ in the solid state was determined by single-crystal X-ray diffraction of [Ir(tn)3......Procedures are given for the preparation and isolation of cis- and trans-[Ir(tn)2Cl2]CF3SO3 and of [Ir(tn)3]Cl3, (tn=propane-1,3-diamine). The compounds were prepared by the use of Ir(thtp)3Cl3 (thtp=tetrahydrothiophene) as starting material, using either DMSO or neat tn as solvent. A procedure......] [Co(CN)6] x 5H2O. The three chelate rings all adopt the energetically favoured chair conformation; however, the overall idealized symmetry is C1. A comparative ligand field analysis, based on Gaussian resolution of the solution UV/VIS spectra for a number of homoleptic [M(N6)]3+ (M=CoIII, RhIII, Ir...

Magnetic structure and excitation spectrum of the hyperhoneycomb Kitaev magnet β -Li2IrO3

Science.gov (United States)

Ducatman, Samuel; Rousochatzakis, Ioannis; Perkins, Natalia B.

2018-03-01

We present a theoretical study of the static and dynamical properties of the three-dimensional, hyperhoneycomb Kitaev magnet β -Li2IrO3 . We argue that the observed incommensurate order can be understood in terms of a long-wavelength twisting of a nearby commensurate period-3 state, with the same key qualitatively features. The period-3 state shows very different structure when either the Kitaev interaction K or the off-diagonal exchange anisotropy Γ is dominant. A comparison of the associated static spin structure factors with reported scattering experiments in zero and finite fields gives strong evidence that β -Li2IrO3 lies in the regime of dominant Kitaev coupling, and that the Heisenberg exchange J is much weaker than both K and Γ . Our predictions for the magnon excitation spectra, the dynamical spin structure factors, and their polarization dependence provide additional distinctive fingerprints that can be checked experimentally.

Proposals of electronic-vibrational energy relaxation studies by using laser pulses synchronized with IR-SR pulses

International Nuclear Information System (INIS)

Nakagawa, Hideyuki

2000-01-01

Synchrotron radiation is expected to be the sharp infrared light source for the advanced experiments on IR and FIR spectroscopy in wide research fields. Especially, synchronized use of SR with VIS and/or UV laser light is to be a promising technique for the research on the dynamical properties of the photo-excited states in condensed materials. Some proposals are attempted for high resolution IR spectroscopy to elucidate fine interaction of molecular ions in crystalline solids with their environmental field and for time-resolved IR spectroscopic studies on the electronic and vibrational energy relaxation by using laser pulses synchronized with IR-SR pulses. Several experimental results are presented in relevance to the subjects; on high-resolution FTIR spectra of cyanide ions and metal cyanide complexes in cadmium halide crystals, on the energy up-conversion process among the vibrational levels of cyanide ions in alkali halide crystals, and on the electronic-to-vibrational energy conversion process in metal cyanide complexes. (author)

Closed-shell and open-shell square-planar iridium nitrido complexes

Science.gov (United States)

Scheibel, Markus G.; Askevold, Bjorn; Heinemann, Frank W.; Reijerse, Edward J.; de Bruin, Bas; Schneider, Sven

2012-07-01

Coupling reactions of nitrogen atoms represent elementary steps to many important heterogeneously catalysed reactions, such as the Haber-Bosch process or the selective catalytic reduction of NOx to give N2. For molecular nitrido (and related oxo) complexes, it is well established that the intrinsic reactivity, for example nucleophilicity or electrophilicity of the nitrido (or oxo) ligand, can be attributed to M-N (M-O) ground-state bonding. In recent years, nitrogen (oxygen)-centred radical reactivity was ascribed to the possible redox non-innocence of nitrido (oxo) ligands. However, unequivocal spectroscopic characterization of such transient nitridyl {M=N•} (or oxyl {M-O•}) complexes remained elusive. Here we describe the synthesis and characterization of the novel, closed-shell and open-shell square-planar iridium nitrido complexes [IrN(Lt-Bu)]+ and [IrN(Lt-Bu)] (Lt-Bu=N(CHCHP-t-Bu2)2). Spectroscopic characterization and quantum chemical calculations for [IrN(Lt-Bu)] indicate a considerable nitridyl, {Ir=N•}, radical character. The clean formation of IrI-N2 complexes via binuclear coupling is rationalized in terms of nitrido redox non-innocence in [IrN(Lt-Bu)].

Photofragmentation of colloidal solutions of gold nanoparticles under femtosecond laser pulses in IR and visible ranges

International Nuclear Information System (INIS)

Danilov, P A; Zayarnyi, D A; Ionin, A A; Kudryashov, S I; Makarov, S V; Rudenko, A A; Saraeva, I N; Yurovskikh, V I; Lednev, V N; Pershin, S M

2015-01-01

The specific features of photofragmentation of sols of gold nanoparticles under focused femtosecond laser pulses in IR (1030 nm) and visible (515 nm) ranges is experimentally investigated. A high photofragmentation efficiency of nanoparticles in the waist of a pulsed laser beam in the visible range (at moderate radiation scattering) is demonstrated; this efficiency is related to the excitation of plasmon resonance in nanoparticles on the blue shoulder of its spectrum, in contrast to the regime of very weak photofragmentation in an IR-laser field of comparable intensity. Possible mechanisms of femtosecond laser photofragmentation of gold nanoparticles are discussed. (extreme light fields and their applications)

Comparison of RF spectrum prediction methods for dynamic spectrum access

Science.gov (United States)

Kovarskiy, Jacob A.; Martone, Anthony F.; Gallagher, Kyle A.; Sherbondy, Kelly D.; Narayanan, Ram M.

2017-05-01

Dynamic spectrum access (DSA) refers to the adaptive utilization of today's busy electromagnetic spectrum. Cognitive radio/radar technologies require DSA to intelligently transmit and receive information in changing environments. Predicting radio frequency (RF) activity reduces sensing time and energy consumption for identifying usable spectrum. Typical spectrum prediction methods involve modeling spectral statistics with Hidden Markov Models (HMM) or various neural network structures. HMMs describe the time-varying state probabilities of Markov processes as a dynamic Bayesian network. Neural Networks model biological brain neuron connections to perform a wide range of complex and often non-linear computations. This work compares HMM, Multilayer Perceptron (MLP), and Recurrent Neural Network (RNN) algorithms and their ability to perform RF channel state prediction. Monte Carlo simulations on both measured and simulated spectrum data evaluate the performance of these algorithms. Generalizing spectrum occupancy as an alternating renewal process allows Poisson random variables to generate simulated data while energy detection determines the occupancy state of measured RF spectrum data for testing. The results suggest that neural networks achieve better prediction accuracy and prove more adaptable to changing spectral statistics than HMMs given sufficient training data.

Technetium-aspirin molecule complexes

International Nuclear Information System (INIS)

El-Shahawy, A.S.; Mahfouz, R.M.; Aly, A.A.M.; El-Zohry, M.

1993-01-01

Technetium-aspirin and technetium-aspirin-like molecule complexes were prepared. The structure of N-acetylanthranilic acid (NAA) has been decided through CNDO calculations. The ionization potential and electron affinity of the NAA molecule as well as the charge densities were calculated. The electronic absorption spectra of Tc(V)-Asp and Tc(V)-ATS complexes have two characteristic absorption bands at 450 and 600 nm, but the Tc(V)-NAA spectrum has one characteristic band at 450 nm. As a comparative study, Mo-ATS complex was prepared and its electronic absorption spectrum is comparable with the Tc-ATS complex spectrum. (author)

Spin orientations of the spin-half Ir(4+) ions in Sr3NiIrO6, Sr2IrO4, and Na2IrO3: Density functional, perturbation theory, and Madelung potential analyses.

Science.gov (United States)

Gordon, Elijah E; Xiang, Hongjun; Köhler, Jürgen; Whangbo, Myung-Hwan

2016-03-21

The spins of the low-spin Ir(4+) (S = 1/2, d(5)) ions at the octahedral sites of the oxides Sr3NiIrO6, Sr2IrO4, and Na2IrO3 exhibit preferred orientations with respect to their IrO6 octahedra. We evaluated the magnetic anisotropies of these S = 1/2 ions on the basis of density functional theory (DFT) calculations including spin-orbit coupling (SOC), and probed their origin by performing perturbation theory analyses with SOC as perturbation within the LS coupling scheme. The observed spin orientations of Sr3NiIrO6 and Sr2IrO4 are correctly predicted by DFT calculations, and are accounted for by the perturbation theory analysis. As for the spin orientation of Na2IrO3, both experimental studies and DFT calculations have not been unequivocal. Our analysis reveals that the Ir(4+) spin orientation of Na2IrO3 should have nonzero components along the c- and a-axis directions. The spin orientations determined by DFT calculations are sensitive to the accuracy of the crystal structures employed, which is explained by perturbation theory analyses when interactions between adjacent Ir(4+) ions are taken into consideration. There are indications implying that the 5d electrons of Na2IrO3 are less strongly localized compared with those of Sr3NiIrO6 and Sr2IrO4. This implication was confirmed by showing that the Madelung potentials of the Ir(4+) ions are less negative in Na2IrO3 than in Sr3NiIrO6 and Sr2IrO4. Most transition-metal S = 1/2 ions do have magnetic anisotropies because the SOC induces interactions among their crystal-field split d-states, and the associated mixing of the states modifies only the orbital parts of the states. This finding cannot be mimicked by a spin Hamiltonian because this model Hamiltonian lacks the orbital degree of freedom, thereby leading to the spin-half syndrome. The spin-orbital entanglement for the 5d spin-half ions Ir(4+) is not as strong as has been assumed.

Elucidation of the electronic spectrum changes of KA-Al{sup 3+} complex by potentiometric titration, FTIR, {sup 13}C NMR and quantum mechanics

Energy Technology Data Exchange (ETDEWEB)

Piantavini, Mário S.; Gonçalves, Alan G.; Trindade, Ângela C.L.B.; Noseda, Miguel D.; Mercê, Ana L.R.; Pontarolo, Roberto, E-mail: pontarolo@ufpr.br [Universidade Federal do Paraná (UFPR), Curitiba (Brazil); Machado, Antonio E.H. [Universidade Federal de Uberlândia (UFU), MG (Brazil)

2017-08-15

Kojic acid (KA) is an organic acid widely used in pharmaceutical industry, mainly as a skin lightening agent. Based on the ability of KA to form complexes with ions, we found the most possible kind of complex formed with cation aluminum. KA-Al{sup 3+} complex structures were studied using potentiometric and spectrophotometric (UV) titrations, FTIR and {sup 13}C NMR. The electronic spectroscopy showed that the KA-Al{sup 3+} complexes absorb at higher wavelengths (λ{sub max}= 305 nm) than do the non-complexed KA (λ{sub max}= 269 nm), confirming complexation. The IR spectra of KA complexed and not complexed allowed to correlate the changes in the absorption of enol and carbonyl groups in absence and presence of Al{sup 3+} in aqueous solutions. The complexation suggested by the potentiometric titration and FTIR spectroscopy are in accordance with the data obtained from NMR results. Calculations based on quantum mechanics were utilized to understand the differences found in the non complexed and complexed KAH electronic spectra. (author)

Current Diagnosis and Management of Immune Related Adverse Events (irAEs Induced by Immune Checkpoint Inhibitor Therapy

Directory of Open Access Journals (Sweden)

Vivek Kumar

2017-02-01

Full Text Available The indications of immune checkpoint inhibitors (ICIs are set to rise further with the approval of newer agent like atezolimumab for use in patients with advanced stage urothelial carcinoma. More frequent use of ICIs has improved our understanding of their unique side effects, which are known as immune-related adverse events (irAEs. The spectrum of irAEs has expanded beyond more common manifestations such as dermatological, gastrointestinal and endocrine effects to rarer presentations involving nervous, hematopoietic and urinary systems. There are new safety data accumulating on ICIs in patients with previously diagnosed autoimmune conditions. It is challenging for clinicians to continuously update their working knowledge to diagnose and manage these events successfully. If diagnosed timely, the majority of events are completely reversible, and temporary immunosuppression with glucocorticoids, infliximab or other agents is warranted only in the most severe grade illnesses. The same principles of management will possibly apply as newer anti- cytotoxic T lymphocytes-associated antigen 4 (CTLA-4 and programmed cell death protein 1 (PD-1/PD-L1 antibodies are introduced. The current focus of research is for prophylaxis and for biomarkers to predict the onset of these toxicities. In this review we summarize the irAEs of ICIs and emphasize their growing spectrum and their management algorithms, to update oncology practitioners.

Intensity dependence of nonsequential double ionization of helium in IR+XUV two-color laser fields

International Nuclear Information System (INIS)

Jin, Facheng; Wang, Bingbing; Chen, Jing; Yang, Yujun; Yan, Zong-Chao

2016-01-01

By applying the frequency-domain theory, we investigate the dependence of momentum spectra on laser intensity in a nonsequential double ionization (NSDI) process of helium in infrared (IR) and extreme ultraviolet (XUV) two-color laser fields. We find that the two-color laser fields play distinct roles in an NSDI process, where the IR laser field mainly determines the width of each band, and the XUV laser field mainly plays a role on the NSDI probability. Furthermore, an NSDI process can be decoupled into a two-step process: an above-threshold ionization (ATI), followed by a laser-assisted collision (LAC). It is found that, the IR laser field is responsible for broadening the peak in the ATI process and providing additional momenta to the two ionized electrons in the LAC process; while the XUV laser field plays a crucial role on the strength of the spectrum in the ATI process, and influences the radii of orbits in momentum space in the LAC process. (paper)

AXION DECAY AND ANISOTROPY OF NEAR-IR EXTRAGALACTIC BACKGROUND LIGHT

Energy Technology Data Exchange (ETDEWEB)

Gong, Yan; Chen, Xuelei [National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012 (China); Cooray, Asantha; Mitchell-Wynne, Ketron [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Zemcov, Michael [Center for Detectors, School of Physics and Astronomy, Rochester Institute of Technology, Rochester, NY 14623 (United States); Smidt, Joseph [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2016-07-10

The extragalactic background light (EBL) is composed of the cumulative radiation from all galaxies and active galactic nuclei over cosmic history. In addition to point sources, the EBL also contains information from diffuse sources of radiation. The angular power spectra of the near-infrared intensities could contain additional signals, and a complete understanding of the nature of the infrared (IR) background is still lacking in the literature. Here we explore the constraints that can be placed on particle decays, especially candidate dark matter (DM) models involving axions that trace DM halos of galaxies. Axions with a mass around a few electronvolts will decay via two photons with wavelengths in the near-IR band and will leave a signature in the IR background intensity power spectrum. Using recent power spectra measurements from the Hubble Space Telescope and the Cosmic Infrared Background Experiment, we find that the 0.6–1.6 μ m power spectra can be explained by axions with masses around 4 eV. The total axion abundance Ω{sub a} ≃ 0.05, and it is comparable to the baryon density of the universe. The suggested mean axion mass and abundance are not ruled out by existing cosmological observations. Interestingly, the axion model with a mass distribution is preferred by the data, which cannot be explained by the standard quantum chromodynamics theory and needs further discussion.

Quasi-simultaneous observations of BL Lac object Mrk 501 in X-ray, UV, visible, IR, and radio frequencies

Science.gov (United States)

Kondo, Y.; Worrall, D. M.; Oke, J. B.; Yee, H. K. C.; Neugebauer, G.; Matthews, K.; Feldman, P. A.; Mushotzky, R. F.; Hackney, R. L.; Hackney, K. R. H.

1981-01-01

Observations in the X-ray, UV, visible, IR and radio regions of the BL Lac object Mrk 501 made over the course of two months are reported. The measurements were made with the A2 experiment on HEAO 1 (X-ray), the SWP and LWR cameras on IUE (UV), the 5-m Hale telescope (visible), the 2.5-m telescope at Mount Wilson (IR), the NRAO 92-m radio telescope at Green Bank (4750 MHz) and the 46-m radio telescope at the Algonquin Observatory (10275 and 10650 MHz). The quasi-simultaneously observed spectral slope is found to be positive and continuous from the X-ray to the UV, but to gradually flatten and possibly turn down from the mid-UV to the visible; the optical-radio emission cannot be accounted for by a single power law. The total spectrum is shown to be compatible with a synchrotron self-Compton emission mechanism, while the spectrum from the visible to the X-ray is consistent with synchrotron radiation or inverse-Compton scattering by a hot thermal electron cloud. The continuity of the spectrum from the UV to the X-ray is noted to imply a total luminosity greater than previous estimates by a factor of 3-4.

Fluorescence, aggregation properties and FT-IR microspectroscopy of elastin and collagen fibers.

Science.gov (United States)

Vidal, Benedicto de Campos

2014-10-01

Histological and histochemical observations support the hypothesis that collagen fibers can link to elastic fibers. However, the resulting organization of elastin and collagen type complexes and differences between these materials in terms of macromolecular orientation and frequencies of their chemical vibrational groups have not yet been solved. This study aimed to investigate the macromolecular organization of pure elastin, collagen type I and elastin-collagen complexes using polarized light DIC-microscopy. Additionally, differences and similarities between pure elastin and collagen bundles (CB) were investigated by Fourier transform-infrared (FT-IR) microspectroscopy. Although elastin exhibited a faint birefringence, the elastin-collagen complex aggregates formed in solution exhibited a deep birefringence and formation of an ordered-supramolecular complex typical of collagen chiral structure. The FT-IR study revealed elastin and CB peptide NH groups involved in different types of H-bonding. More energy is absorbed in the vibrational transitions corresponding to CH, CH2 and CH3 groups (probably associated with the hydrophobicity demonstrated by 8-anilino-1-naphtalene sulfonic acid sodium salt [ANS] fluorescence), and to νCN, δNH and ωCH2 groups of elastin compared to CB. It is assumed that the α-helix contribution to the pure elastin amide I profile is 46.8%, whereas that of the B-sheet is 20% and that unordered structures contribute to the remaining percentage. An FT-IR profile library reveals that the elastin signature within the 1360-1189cm(-1) spectral range resembles that of Conex-Toray aramid fibers. Copyright © 2014 Elsevier GmbH. All rights reserved.

Changes in Cell Viability of Wounded Fibroblasts following Laser Irradiation in Broad-Spectrum or Infrared Light

International Nuclear Information System (INIS)

Hawkins, D.; Abrahamse, H.

2007-01-01

Objective. This study aimed to establish if broad-spectrum or infrared (IR) light in combination with laser therapy can assist phototherapy to improve the cell function of wounded cells. Background. The effect of laser light may be partly or completely reduced by broad-spectrum light. Methods. Wounded human skin fibroblasts were irradiated with 5 J/cm2 using a helium-neon laser, a diode laser, or an Nd:YAG laser in the dark, in the light, or in IR. Changes in cell viability were evaluated by cell morphology, ATP cell viability, LDH membrane integrity, and caspase 3/7 as an early marker of apoptosis. Results. Wounded cells exposed to 5 J/cm2 using 632.8 nm in the dark or 830 nm in the light or 1064 nm in the dark showed an increase in ATP viability, an increase in cytokine expression, and a decrease in LDH cytotoxicity indicating that the metabolic activity of the wounded cells was stimulated. Conclusion. Wounded cells irradiated in IR light showed an undesirable thermal effect that was proportional to the duration of exposure.

Optical design for a breadboard high-resolution spectrometer for SIRTF/IRS

Science.gov (United States)

Brown, Robert J.; Houck, James R.; van Cleve, Jeffrey E.

1996-11-01

The optical design of a breadboard high resolution infrared spectrometer for the IRS instrument on the SIRTF mission is discussed. The spectrometer uses a crossed echelle grating configuration to cover the spectral region from 10 to 20 micrometer with a resolving power of approximately equals 600. The all reflective spectrometer forms a nearly diffraction limited image of the two dimensional spectrum on a 128 multiplied by 128 arsenic doped silicon area array with 75 micrometer pixels. The design aspects discussed include, grating numerology, image quality, packaging and alignment philosophy.

Spectral, thermal, kinetic, molecular modeling and eukaryotic DNA degradation studies for a new series of albendazole (HABZ) complexes

Science.gov (United States)

El-Metwaly, Nashwa M.; Refat, Moamen S.

2011-01-01

This work represents the elaborated investigation for the ligational behavior of the albendazole ligand through its coordination with, Cu(II), Mn(II), Ni(II), Co(II) and Cr(III) ions. Elemental analysis, molar conductance, magnetic moment, spectral studies (IR, UV-Vis and ESR) and thermogravimetric analysis (TG and DTG) have been used to characterize the isolated complexes. A deliberate comparison for the IR spectra reveals that the ligand coordinated with all mentioned metal ions by the same manner as a neutral bidentate through carbonyl of ester moiety and NH groups. The proposed chelation form for such complexes is expected through out the preparation conditions in a relatively acidic medium. The powder XRD study reflects the amorphous nature for the investigated complexes except Mn(II). The conductivity measurements reflect the non-electrolytic feature for all complexes. In comparing with the constants for the magnetic measurements as well as the electronic spectral data, the octahedral structure was proposed strongly for Cr(III) and Ni(II), the tetrahedral for Co(II) and Mn(II) complexes but the square-pyramidal for the Cu(II) one. The thermogravimetric analysis confirms the presence or absence of water molecules by any type of attachments. Also, the kinetic parameters are estimated from DTG and TG curves. ESR spectrum data for Cu(II) solid complex confirms the square-pyramidal state is the most fitted one for the coordinated structure. The albendazole ligand and its complexes are biologically investigated against two bacteria as well as their effective effect on degradation of calf thymus DNA.

PREPARATION AND PROPERTIES OF THREE NEUTRAL COPPER (I COMPLEXES BASED ON BIS[2-(DIPHENYLPHOSPHINOPHENYL]ETHER PHENYL] ETHER AND SUBSTITUTED IMIDAZOLE-2,9-DIMETHYL-1,10-PHENANTHROLINE

Directory of Open Access Journals (Sweden)

Xin Fang Liu

2017-10-01

Full Text Available With deprotonated 2-(4-nitro phenyl-, 2-(4-methyl phenyl-, and 2-(4-methoxy phenyl imidazoled-2,9-dimethyl-1,10-phenanthroline (NPIP, MPIP and MoPIP as nitrogen ligands, as well as bis[2-(diphenylphosphino phenyl]ether (DPEphos as phosphorus ligand, three Cu(I neutral complex has been synthesized and characterized by infrared spectroscopy (IR, elemental analysis and 1H NMR methods. TG-DTA shows that the complex begins to decompose when the temperature reached about 220 oC, indicating their high thermo-stability. The emission spectrum shows that the complexes exhibit yellow emission with a peak emission wavelength of 576, 585 and 596 nm under excitation of 287 nm in powder state.

Tidal Distortion of the Envelope of an AGB Star IRS 3 near Sgr A{sup *}

Energy Technology Data Exchange (ETDEWEB)

Yusef-Zadeh, F.; Royster, M. J.; Roberts, D. A. [Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Wardle, M. [Department of Physics and Astronomy and Research Center for Astronomy, Astrophysics and Astrophotonics, Macquarie University, Sydney NSW 2109 (Australia); Cotton, W.; Kunneriath, D. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Schödel, R. [Instituto de Astfisica de Andalucia (CSIC), Glorieta de la Astronomia S/N, E-18008 Granada (Spain)

2017-03-01

We present radio and millimeter continuum observations of the Galactic center taken with the Very Large Array (VLA) and ALMA at 44 and 226 GHz, respectively. We detect radio and millimeter emission from IRS 3, lying ∼4.″5 NW of Sgr A*, with a spectrum that is consistent with the photospheric emission from an AGB star at the Galactic center. Millimeter images reveal that the envelope of IRS 3, the brightest and most extended 3.8 μ m Galactic center stellar source, consists of two semicircular dust shells facing the direction of Sgr A*. The outer circumstellar shell, at a distance of 1.6 × 10{sup 4} au, appears to break up into “fingers” of dust directed toward Sgr A*. These features coincide with molecular CS (5–4) emission and a near-IR extinction cloud distributed between IRS 3 and Sgr A*. The NE–SW asymmetric shapes of the IRS 3 shells seen at 3.8 μ m and radio are interpreted as structures that are tidally distorted by Sgr A*. Using the kinematics of CS emission and the proper motion of IRS 3, the tidally distorted outflowing material from the envelope after 5000 yr constrains the distance of IRS 3 to ∼0.7 pc in front of or ∼0.5 pc behind Sgr A*. This suggests that the mass loss by stars near Sgr A* can supply a reservoir of molecular material near Sgr A*. We also present dark features in radio continuum images coincident with the envelope of IRS 3. These dusty stars provide examples in which high-resolution radio continuum images can identify dust-enshrouded stellar sources embedded in an ionized medium.

The Social Living Complex: A New, All Day, Yearlong Intervention Model for Individuals with Autism Spectrum Disorder and Their Parents

Science.gov (United States)

Doenyas, Ceymi

2016-01-01

We propose an unprecedented intervention for individuals with autism spectrum disorder (ASD) and their parents: the social living complex. Unlike existing social skills interventions, peer-mediated interventions here are not limited to the school/experiment duration and setting. Whereas other supported living services house adults with ASD only,…

Joint attention responses of children with autism spectrum disorder to simple versus complex music.

Science.gov (United States)

Kalas, Amy

2012-01-01

Joint attention deficits are viewed as one of the earliest manifestations and most characteristic features of the social deficits in Autism Spectrum Disorder (ASD). The purpose of this study was to examine the effect of simple versus complex music on joint attention of children with ASD. Thirty children with a diagnosis of ASD participated in this study. Fifteen of the participants were diagnosed with severe ASD and 15 were diagnosed with mild/moderate ASD. Each participant took part in six, 10-minute individual music conditions (3 simple & 3 complex) over a 3-week period. Each condition was designed to elicit responses to joint attention. RESULTS indicated a statistically significant interaction between music modality and functioning level. Therefore, the effect of simple versus complex music was dependent on functioning level. Specifically, the Simple Music Condition was more effective in eliciting Responses to Joint Attention (RJA) for children diagnosed with severe ASD, whereas the Complex Music Condition was more effective in eliciting RJA for children diagnosed with mild/moderate ASD. The results of the present study indicate that for children in the severe range of functioning, music that is simple, with clear and predictable pattems, may be most effective in eliciting responses to bids for joint attention. On the contrary, for children in the mild/moderate range of functioning, music that is more complex and variable may be most effective in eliciting responses to bids for joint attention. These results demonstrate that careful manipulation of specific musical elements can help provide the optimal conditions for facilitating joint attention with children with ASD.

Suppression of superconductivity in Nb by IrMn in IrMn/Nb bilayers

KAUST Repository

Wu, B. L.

2013-10-10

Effect of antiferromagnet on superconductivity has been investigated in IrMn/Nb bilayers. Significant suppression of both transition temperature (Tc) and lower critical field (Hc1) of Nb is found in IrMn/Nb bilayers as compared to a single layer Nb of same thickness; the suppression effect is even stronger than that of a ferromagnet in NiFe/Nb bilayers. The addition of an insulating MgO layer at the IrMn-Nb interface nearly restores Tc to that of the single layer Nb, but Hc1 still remains suppressed. These results suggest that, in addition to proximity effect and magnetic impurity scattering, magnetostatic interaction also plays a role in suppressing superconductivity of Nb in IrMn/Nb bilayers. In addition to reduced Tc and Hc1, the IrMn layer also induces broadening in the transition temperature of Nb, which can be accounted for by a finite distribution of stray field from IrMn.

Synthesis and characterization of La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III) and Dy(III) complexes of 2-acetylfuran-2-thenoylhydrazone

International Nuclear Information System (INIS)

Singh, B.; Singh, Praveen K.

1998-01-01

The reaction of 2-acetylfuran-2-thenoylhydrazone(afth) with Ln(III) trichlorides yields complexes of the type [Ln(afth)Cl 2 (H 2 O)(EtOH)]Cl, [Ln(III) = La, Pr, Nd, Sm, Eu, Gd, Tb and Dy]. The complexes have been characterized by molar conductance, magnetic susceptibility and TGA and DTA measurements, magnetic susceptibility and TGA and DTA measurements, FAB mass, infrared, proton NMR, electronic absorption and emission spectra. The terbium complex is found to be monomer from the FAB mass spectrum. The IR and NMR spectra suggest neutral tridentate behaviour of the Schiff base. A coordination number seven is proposed around the metal ions. Emission spectra suggest C 3v , symmetry around the metal ion with capped octahedron geometry for the europium complex. (author)

Mechanism of CO 2 Fixation by Ir I -X Bonds (X = OH, OR, N, C)

KAUST Repository

Vummaleti, Sai V. C.; Talarico, Giovanni; Nolan, Steven P.; Cavallo, Luigi; Poater, Albert

2015-01-01

Density functional theory calculations have been used to investigate the CO2 fixation mechanism proposed by Nolan et al. for the IrI complex [Ir(cod)(IiPr)(OH)] (1; cod = 1,5-cyclooctadiene; IiPr = 1,3-diisopropylimidazol-2-ylidene) and its derivatives. For 1, our results suggest that CO2 insertion is the rate-limiting step rather than the dimerization step. Additionally, in agreement with the experimental results, our results show that CO2 insertion into the Ir-OR1 (R1 = H, methyl, and phenyl) and Ir-N bonds is kinetically facile, and the calculated activation energies span a range of only 12.0-23.0 kcal/mol. Substantially higher values (35.0-50.0 kcal/mol) are reported for analogous Ir-C bonds. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mechanism of CO 2 Fixation by Ir I -X Bonds (X = OH, OR, N, C)

KAUST Repository

Vummaleti, Sai V. C.

2015-09-08

Density functional theory calculations have been used to investigate the CO2 fixation mechanism proposed by Nolan et al. for the IrI complex [Ir(cod)(IiPr)(OH)] (1; cod = 1,5-cyclooctadiene; IiPr = 1,3-diisopropylimidazol-2-ylidene) and its derivatives. For 1, our results suggest that CO2 insertion is the rate-limiting step rather than the dimerization step. Additionally, in agreement with the experimental results, our results show that CO2 insertion into the Ir-OR1 (R1 = H, methyl, and phenyl) and Ir-N bonds is kinetically facile, and the calculated activation energies span a range of only 12.0-23.0 kcal/mol. Substantially higher values (35.0-50.0 kcal/mol) are reported for analogous Ir-C bonds. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lecithin Complex

African Journals Online (AJOL)

1Department of Food Science and Engineering, Xinyang College of Agriculture and ... Results: The UV and IR spectra of the complex showed an additive effect of polydatin-lecithin, in which .... Monochromatic Cu Ka radiation (wavelength =.

Base free N-alkylation of anilines with ArCH2OH and transfer hydrogenation of aldehydes/ketones catalyzed by the complexes of η5-Cp*Ir(iii) with chalcogenated Schiff bases of anthracene-9-carbaldehyde.

Science.gov (United States)

Dubey, Pooja; Gupta, Sonu; Singh, Ajai K

2018-03-12

The condensation of anthracene-9-carbaldehyde with 2-(phenylthio/seleno)ethylamine results in Schiff bases [PhS(CH 2 ) 2 C[double bond, length as m-dash]N-9-C 14 H 9 ](L1) and [PhSe(CH 2 ) 2 C[double bond, length as m-dash]N-9-C 14 H 9 ] (L2). On their reaction with [(η 5 -Cp*)IrCl(μ-Cl)] 2 and CH 3 COONa at 50 °C followed by treatment with NH 4 PF 6 , iridacycles, [(η 5 -Cp*)Ir(L-H)][PF 6 ] (1: L = L1; 2: L = L2), result. The same reaction in the absence of CH 3 COONa gives complexes [(η 5 -Cp*)Ir(L)Cl][PF 6 ] (3-4) in which L = L1(3)/L2(4) ligates in a bidentate mode. The ligands and complexes were authenticated with HR-MS and NMR spectra [ 1 H, 13 C{ 1 H} and 77 Se{ 1 H} (in the case of L2 and its complexes only)]. Single crystal structures of L2 and half sandwich complexes 1-4 were established with X-ray crystallography. Three coordination sites of Ir in each complex are covered with η 5 -Cp* and on the remaining three, donor atoms present are: N, S/Se and C - /Cl - , resulting in a piano-stool structure. The moisture and air insensitive 1-4 act as efficient catalysts under mild conditions for base free N-alkylation of amines with benzyl alcohols and transfer hydrogenation (TH) of aldehydes/ketones. The optimum loading of 1-4 as a catalyst is 0.1-0.5 mol% for both the activations. The best reaction temperature is 80 °C for transfer hydrogenation and 100 °C for N-alkylation. The mercury poisoning test supports a homogeneous pathway for both the reactions catalyzed by 1-4. The two catalytic processes are most efficient with 3 followed by 4 > 1 > 2. The mechanism proposed on the basis of HR-MS of the reaction mixtures of the two catalytic processes taken after 1-2 h involves the formation of an alkoxy and hydrido species. The real catalytic species proposed in the case of iridacycles results due to the loss of the Cp* ring.

Possible connection between the location of the cutoff in the cosmic microwave background spectrum and the equation of state of dark energy.

Science.gov (United States)

Enqvist, Kari; Sloth, Martin S

2004-11-26

We investigate a possible connection between the suppression of the power at low multipoles in the cosmic microwave background (CMB) spectrum and the late time acceleration. We show that, assuming a cosmic IR/UV duality between the UV cutoff and a global infrared cutoff given by the size of the future event horizon, the equation of state of the dark energy can be related to the apparent cutoff in the CMB spectrum. The present limits on the equation of state of dark energy are shown to imply an IR cutoff in the CMB multipole interval of 9>l>8.5.

An exploration of imitation recognition in young children with autism spectrum disorders.

Science.gov (United States)

Berger, Natalie I; Ingersoll, Brooke

2013-10-01

The ability to recognize when one is being imitated has been hypothesized to be an important developmental process related to the emergence of more advanced social-cognitive skills. While a series of behaviors indicating progressively more mature imitation recognition (IR) skills has been assessed in typically developing children, empirical work with children with autism spectrum disorders (ASDs) has largely focused on basic social responses to an imitative adult (e.g. increases in eye contact). Limited work has explored more mature IR behaviors in this population. This study compared the degree to which children with ASD engage in different behaviors thought to be indicative of IR during a naturalistic imitation task and the relationship between different types of IR behaviors and social-cognitive skills (i.e. imitation, language, social reciprocity, and joint attention). Thirty children with ASD were administered standardized measures of cognitive level, language, joint attention, social reciprocity, and imitation. IR behaviors were observed during periods of contingent imitation by an adult. Participants engaged more frequently in less mature (e.g. looking at the experimenter's toy or face) than more mature IR behaviors (e.g. testing the experimenter's intent to imitate). After controlling for developmental level, social reciprocity, object imitation, and gesture imitation were positively correlated with more mature IR. These findings suggest that the development of more mature IR skills is related to the development of other social-cognitive skills in children with ASD and provide additional empirical support for reports of more mature IR observed in this population. , Inc. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.

Structure, magnetism, and transport properties for Ca doping in Sr2IrO4

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Guotai Zhou

2017-05-01

Full Text Available An immediate quenching using liquid N2 is applied for synthesizing the 5d transition-metal oxides (Sr1-xCax2IrO4 (0 ≤ x ≤ 0.15 single phase. X-ray diffraction together with Rietveld refinement shows that the lattice parameters along a and c directions and the bond angle of Ir-O2-Ir decrease with the increase of Ca content. X-ray Absorption Fine Spectroscopy measurements prove that the valence of Ir and the average Ir-O bond-length substantially remain unchanged with Ca content increasing in the phase. The effective magnetic moment μeff and Néel temperature TN decrease simultaneously with increased Ca content. Electrical resistivity shows complex temperature dependence behavior, which follows the three-dimensional variable range hopping behavior at low temperature, Arrhenius-type behavior at middle-temperature, and a weak electronic localization in quasi-two-dimensional at high temperature.

Synthesis and characterization of Ni(II, Cu(II and Co(III complexes with polyamine-containing macrocycles bearing an aminoethyl pendant arm

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K. S. SIDDIQI

2004-09-01

Full Text Available Reaction of [M(ppn2]X2 (where M = Cu(II, Ni(II, Co(II and ppn = 1,3-diaminopropane with formaldehyde and ethylenediamine in methanol results in the ready formation of a 16-membered macrocyclic complex. The complexes were characterized by elemental anlysis, IR, EPR, electronic spectral data, magnetic moments and conductance measurements. The Cu(II, Ni(II and Co(III complexes are coordinated axially with both pendant groups of the hexadentate macrocycle. These pendant donors are attached to the macrocycle by a carbon chain. The electrical conductivities of the Cu(II and Ni(II chelates indicated them to be 1:2 electrolytes whilst those of Co(III is a 1:3 electrolyte in DMSO. The EPR spectrum of the copper complex exhibited G at 3.66, which indicates a considerable exchange interaction in the complex. Spectroscopic evidence suggests that in all of the complexes the metal ion is in an octahedral environment.

Synthesis and electrophosphorescence of iridium complexes containing benzothiazole-based ligands.

Science.gov (United States)

Liu, Di; Ren, Huicai; Deng, Lijun; Zhang, Ting

2013-06-12

Four heteroleptic bis-cyclometalated iridium(III) complexes containing 2-aryl-benzothiazole ligands, in which the aryl is dibenzofuran-2-yl [Ir(O-bt)2(acac)], dibenzothiophene-2-yl [Ir(S-bt)2(acac)], dibenzothiophene-S,S-dioxide-2-yl [Ir(SO2-bt)2(acac)] and 4-(diphenylphosphoryl)phenyl [Ir(PO-bt)2(acac)], have been synthesized and characterized for use in organic light-emitting diodes (OLEDs). These complexes emit bright yellow (551 nm) to orange-red (598 nm) phosphorescence at room temperature, the peak wavelengths of which can be finely tuned depending upon the electronic properties of the aryl group in the 2-position of benzothiazole. The strong electron-withdrawing aryls such as dibenzothiophene-S,S-dioxide2-yl and 4-(diphenylphosphoryl)phenyl caused bathochromatic shift of the iridium complex phosphorescence. These iridium complexes were used as doped emitters to fabricate yellow to orange-red OLEDs and good performance was obtained. In particular, a maximum luminance efficiency of 58.4 cd A(-1) (corresponding to 30.6 lm W(-1) and 19%) with CIE coordinates of (0.45, 0.52) was achieved for Ir(O-bt)2(acac)-based yellow device. Furthermore, the yellow emitting Ir(S-bt)2(acac) was used to fabricate two-element white OLED that exhibited a high efficiency of 32.4 cd A(-1) with CIE coordinates of (0.28, 0.44).

VizieR Online Data Catalog: IR-bright MSX sources in the SMC with Spitzer/IRS (Kraemer+, 2017)

Science.gov (United States)

Kraemer, K. E.; Sloan, G. C.; Wood, P. R.; Jones, O. C.; Egan, M. P.

2017-07-01

Our original set of infrared spectra of MSX SMC sources was obtained in Spitzer Cycle 1 (Program ID 3277, P.I. M. Egan). This program included 35 targets from the MSX SMC catalog. 24 targets were discussed in previous papers; this paper examines the remaining 11 sources in the sample. We also selected 4 objects in the MSX SMC catalog with similar photometric characteristics in an effort to uncover additional sources with crystalline dust. We observed these targets in Spitzer Cycle 3 (Program ID 30355, P.I. J. Houck). See tables 1 and 2 for observation data and basic properties of the targets. Table 3 lists 20 additional MSX SMC sources that were observed by other Spitzer IRS programs. Overall, 59 MSX SMC sources were observed with the IRS. The spectra were observed using the low-resolution modules of the IRS, Short-Low (SL) and Long-Low (LL), which provided spectra in the 5-14 and 14-37um ranges, respectively, at a resolution between ~60 and 120. For 10 evolved stars with oxygen-rich dust in our Cycle 1 program, we obtained spectra from 0.45 to 1.03um with the Double-Beam Spectrograph at the 2.3m telescope of the Australian National University at Siding Spring Observatory. A 0.45-0.89um spectrum for one of the stars in program 30355 was also observed. These spectra have a resolution of 10Å. Tables 5-7: catalog based on the 243 sources detected in the MSX survey of the SMC, updated with positions and photometry from more recent space-based missions and ground-based surveys. See the Appendix section for more details. The SMC catalog from MSX consists of the 243 sources in the main MSX catalog (Egan+ 2003, see V/114) that lie within the region 7°

IDENTIFICATION OF SOME COMPOSITE MEDICINAL DRUGS CONTAINING PARACETAMOL, WITH IR-SPECTROMETRY METHOD

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A. S. Saushkina

2017-01-01

Full Text Available A serious threat to the health of the population is falsified medicines. In a number of cases, they are identified in the process of incoming quality control for compliancewith the requirements of regulatory documents for indicators “Description”, “Packaging”, “Marking”. However, in order to identify sophisticated counterfeits, only a visual assessment of the drug is not enough. Purpose screening evaluation of potentiallycounterfeited or poor-quality drugs using the IR spectrometry along the total spectrum.Materials and methods. The objects of research were available in freely availablecommercially available tablets produced by domestic and foreign manufacturers“Paracetamol Extratab”, “Solpadein fast”, “Citrapac”, “Citramon P”, “Ascofen-P”,  corresponding to the requirements of the current regulatory documents. The studies were carried out on a Fourier-Spectrophotometer infrared “FSM 1201”. Results and discussion. On the example of the tablets “Citramon P”, “Ascophen-P”, “Citrapac”, “Paracetamol Extratab”, “Solpadein Fast” the possibility of using the total IR spectra as a primary screening index of authenticity is shown. It was established that the total IR spectra of medicines of similar composition reflect the similarity of serial samples of the products ofone manufacturer and the difference in serial samples of products of different manufacturers.

Critical Dispersion-Theory Tests of Silicon's IR Refractive Index

Science.gov (United States)

Karstens, William; Smith, D. Y.

Silicon strongly absorbs both visible and UV light, but is highly transparent in the IR. Hence, it is a common choice for infrared windows and lenses. However, optical design is hindered by literature index values that disagree by up to 1%. In contrast optical-glass indices are known to 0.01% or better. The most widely available silicon IR indices are based on bulk measurements using either Snell's-Law refraction by a prism or channel-spectra interference of front- and backsurface reflections from a planar sample. To test the physical acceptability of these data, we have developed criteria based on a Taylor expansion of the Kramers-Kronig relation for the index at energies below strong inter-band transitions. These tests require that the coefficients of the series in powers of energy squared must be positive within the region of transparency. This is satisfied by essentially all prism measurements; their small scatter arises primarily from impurities and doping. In contrast, channel-spectra data fail in the second and third coefficients. A review of the experimental analysis indicates three problems besides purity: incorrect channel number arising from a channel-spectra model that neglects spectrum distortion by the weak lattice absorption; use of a series expansion of mixed parity in photon energy to describe the even-parity index; and use of an incorrect absorption energy in the Li-Sellmeier dispersion formula. Recommendations for IR index values for pure silicon will be discussed. Supported in part by the US Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC02-06CH11357.

Mesoporous silica nanoparticle supported PdIr bimetal catalyst for selective hydrogenation, and the significant promotional effect of Ir

Energy Technology Data Exchange (ETDEWEB)

Yang, Hui; Huang, Chao; Yang, Fan [The Key Laboratory of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641 (China); Yang, Xu [Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou (China); Du, Li [The Key Laboratory of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641 (China); Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou (China); Liao, Shijun, E-mail: chsjliao@scut.edu.cn [The Key Laboratory of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641 (China); Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou (China)

2015-12-01

Graphical abstract: A mesoporous silica nanoparticle (MSN) supported bimetal catalyst, PdIr/MSN, was prepared by a facile impregnation and hydrogen reduction method. The strong promotional effect of Ir was observed and thoroughly investigated. At the optimal molar ratio of Ir to Pd (N{sub Ir}/N{sub Pd} = 0.1), the activity of PdIr{sub 0.1}/MSN was up to eight times and 28 times higher than that of monometallic Pd/MSN and Ir/MSN, respectively. The catalysts were characterized comprehensively by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and hydrogen temperature programmed reduction, which revealed that the promotional effect of Ir may be due to the enhanced dispersion of active components on the MSN, and to the intensified Pd–Ir electronic interaction caused by the addition of Ir. - Highlights: • Mesoporous nanoparticles were synthesized and used as support for metal catalyst. • PdIr bimetallic catalyst exhibited significantly improved hydrogenation activity. • The strong promotion of Ir was recognized firstly and investigated intensively. • PdIr exhibits 18 times higher activity than Pd to the hydrogenation of nitrobenzene. - Abstract: A mesoporous silica nanoparticle (MSN) supported bimetal catalyst, PdIr/MSN, was prepared by a facile impregnation and hydrogen reduction method. The strong promotional effect of Ir was observed and thoroughly investigated. At the optimal molar ratio of Ir to Pd (N{sub Ir}/N{sub Pd} = 0.1), the activity of PdIr{sub 0.1}/MSN was up to eight times and 28 times higher than that of monometallic Pd/MSN and Ir/MSN, respectively. The catalysts were characterized comprehensively by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and hydrogen temperature programmed reduction, which revealed that the promotional effect of Ir may be due to the enhanced dispersion of active components on the MSN, and to the intensified Pd–Ir electronic interaction

Study on an x-ray microcalorimeter using Ir superconductor

International Nuclear Information System (INIS)

Kunieda, Yuichi; Zen, Nobuyuki; Nakazawa, Masaharu; Takahashi, Hiroyuki; Fukuda, Daiji; Ohkubo, Masataka

2005-01-01

We fabricated a ten-pixel Ir/Au-transition edge sensor (TES) microcalorimeter, and investigated its signal and noise-property. The device was successfully operated in electro-thermal feedback (ETF) mode. More than six position groups could be discrete by using pulse height and rise time parameters of observed x-ray signals. It seems that the separation groups reflect the pixel position of the TES. The best energy resolution was 18.8 eV (FWHM) for 5.9 keV. The noise spectrum showed that noise level of ten-pixel was larger than that of single pixel. A unexplained peak was observed in the plot of current noise for each bias point. (author)

BOOTES-IR: near IR follow-up GRB observations by a robotic system

International Nuclear Information System (INIS)

Castro-Tirado, A.J.; Postrigo, A. de Ugarte; Jelinek, M.

2005-01-01

BOOTES-IR is the extension of the BOOTES experiment, which operates in Southern Spain since 1998, to the near IR (NIR). The goal is to follow up the early stage of the gamma ray burst (GRB) afterglow emission in the NIR, alike BOOTES does already at optical wavelengths. The scientific case that drives the BOOTES-IR performance is the study of GRBs with the support of spacecraft like INTEGRAL, SWIFT and GLAST. Given that the afterglow emission in both, the NIR and the optical, in the instances immediately following a GRB, is extremely bright (reached V = 8.9 in one case), it should be possible to detect this prompt emission at NIR wavelengths too. The combined observations by BOOTES-IR and BOOTES-1 and BOOTES-2 will allow for real time identification of trustworthy candidates to have a high redshift (z > 5). It is expected that, few minutes after a GRB, the IR magnitudes be H ∼ 7-10, hence very high quality spectra can be obtained for objects as far as z = 10 by larger instruments

Development of Cytoplasmic Male Sterile IR24 and IR64 Using CW-CMS/Rf17 System.

Science.gov (United States)

Toriyama, Kinya; Kazama, Tomohiko

2016-12-01

A wild-abortive-type (WA) cytoplasmic male sterility (CMS) has been almost exclusively used for breeding three-line hybrid rice. Many indica cultivars are known to carry restorer genes for WA-CMS lines and cannot be used as maintainer lines. Especially elite indica cultivars IR24 and IR64 are known to be restorer lines for WA-CMS lines, and are used as male parents for hybrid seed production. If we develop CMS IR24 and CMS IR64, the combination of F1 pairs in hybrid rice breeding programs will be greatly broadened. For production of CMS lines and restorer lines of IR24 and IR64, we employed Chinese wild rice (CW)-type CMS/Restorer of fertility 17 (Rf17) system, in which fertility is restored by a single nuclear gene, Rf17. Successive backcrossing and marker-assisted selection of Rf17 succeeded to produce completely male sterile CMS lines and fully restored restorer lines of IR24 and IR64. CW-cytoplasm did not affect agronomic characteristics. Since IR64 is one of the most popular mega-varieties and used for breeding of many modern varieties, the CW-CMS line of IR64 will be useful for hybrid rice breeding.

The TApIR experiment. IR absorption spectra of liquid hydrogen isotopologues

International Nuclear Information System (INIS)

Groessle, Robin

2015-01-01

The scope of the thesis is the infrared absorption spectroscopy of liquid hydrogen isotopologues with the tritium absorption infrared spectroscopy (TApIR) experiment at the tritium laboratory Karlsruhe (TLK). The calibration process from the sample preparation to the reference measurements are described. A further issue is the classical evaluation of FTIR absorption spectra and the extension using the rolling circle filter (RCF) including the effects on statistical and systematical errors. The impact of thermal and nuclear spin temperature on the IR absorption spectra is discussed. An empirical based modeling for the IR absorption spectra of liquid hydrogen isotopologues is performed.

THE HI INFRARED LINE SPECTRUM FOR BE STARS WITH LOW-DENSITY DISCS

NARCIS (Netherlands)

ZAAL, PA; WATERS, LBFM; MARLBOROUGH, JM

We present theoretical H alpha and HI infrared recombination line calculations for low-density discs around B stars. Such a disc shows no visible emission in H alpha, while the HI IR recombination lines are in emission. This phenomenon has been found in the spectrum of the B0.2V star, tau Sco and

IR characteristic simulation of city scenes based on radiosity model

Science.gov (United States)

Xiong, Xixian; Zhou, Fugen; Bai, Xiangzhi; Yu, Xiyu

2013-09-01

Reliable modeling for thermal infrared (IR) signatures of real-world city scenes is required for signature management of civil and military platforms. Traditional modeling methods generally assume that scene objects are individual entities during the physical processes occurring in infrared range. However, in reality, the physical scene involves convective and conductive interactions between objects as well as the radiations interactions between objects. A method based on radiosity model describes these complex effects. It has been developed to enable an accurate simulation for the radiance distribution of the city scenes. Firstly, the physical processes affecting the IR characteristic of city scenes were described. Secondly, heat balance equations were formed on the basis of combining the atmospheric conditions, shadow maps and the geometry of scene. Finally, finite difference method was used to calculate the kinetic temperature of object surface. A radiosity model was introduced to describe the scattering effect of radiation between surface elements in the scene. By the synthesis of objects radiance distribution in infrared range, we could obtain the IR characteristic of scene. Real infrared images and model predictions were shown and compared. The results demonstrate that this method can realistically simulate the IR characteristic of city scenes. It effectively displays the infrared shadow effects and the radiation interactions between objects in city scenes.

Preliminary study of corrosion mechanisms of actinides alloys: calibration of FT-IR spectroscopy

International Nuclear Information System (INIS)

Magnien, Veronique; Cadignan, Marx; Faivret, Olivier; Rosa, Gaelle

2008-01-01

In situ analyzes of gaseous atmospheres could be performed by FT-IR spectroscopy in order to study the corrosion reactions of actinides. Nevertheless experimental conditions and the nature of studied species have a strong effect on IR absorption laws. Thus a prior calibration of our set-up is required to obtain an accurate estimation of gas concentration. For this purpose, the behavior of several air pure gases has been investigated according to their concentration from IR spectra. Reproducible results revealed subsequent increases of the most significant peak areas with gas pressure and small deviations from Beer Lambert's law. This preliminary work allowed to determine precise absorption laws for each studied pure gas in our in situ experimental conditions. Besides our FT-IR set-up was well suitable to quantitative analysis of gaseous atmosphere during corrosion reactions. Finally the effect of foreign gas will be investigated through more complex air mixtures to obtain a complete calibration network. (authors)

Near-infrared-emitting heteroleptic cationic iridium complexes derived from 2,3-diphenylbenzo[g]quinoxaline as in vitro theranostic photodynamic therapy agents

Energy Technology Data Exchange (ETDEWEB)

Wang, Li; Yin, Huimin; Cui, Peng; Hetu, Marc; Wang, Chengzhe; Monro, Susan; Schaller, Richard D.; Cameron, Colin G.; Liu, Bingqing; Kilina, Svetlana; McFarland, Sherri A.; Sun, Wenfang

2017-05-19

Five heteroleptic cationic iridium complexes with a π-expansive cyclometalating 2,3-diphenylbenzo[g] quinoxaline (dpbq) ligand (C^N ligand) and different diimine ligands (N^N ligands) (i.e. 2,2’-bipyridine (bpy, 1), phenanthroline (phen, 2), 2-(2-pyridinyl)quinoline (pqu, 3), 2,2’-bisquinoline (bqu, 4), and 2-(quinolin-2-yl)quinoxaline (quqo, 5)) were synthesized and characterized. The lowest-energy singlet electronic transitions (S1 states) were mainly dpbq ligand-centred 1ILCT (intraligand charge transfer)/1MLCT (metal to ligand charge transfer) transitions mixed with some 1π,π* transitions for complexes 1–4 with increased contributions from 1LLCT (ligand to ligand charge transfer) in 3 and 4. For complex 5, the S1 state was switched to the 1LLCT/1MLCT transitions. All five complexes displayed weak near-infrared (NIR) phosphorescence, with maximal emission output spanning 700–1400 nm and quantum yields being on the order of 10-3. The triplet state absorptions of 1–4 all resembled that of the [Ir(dpbq)2Cl]2 dimer with lifetimes of ca. 400 ns, while the TA spectrum of 5 possessed the characteristics of both the quqo ligand and the [Ir(dpbq)2Cl]2 dimer with a bi-exponential decay of ca. 5 μs and 400 ns. While the photophysics of these complexes differ slightly, their theranostic photodynamic therapy (PDT) effects varied drastically. All of the complexes were biologically active toward melanoma cells. Complexes 2 and 3 were the most cytotoxic, with 230–340 nM activity and selectivity factors for melanoma cells over normal skin fibroblasts of 34 to 40 fold. Complexes 2, 3, and 5 became very potent cytotoxins with light activation, with EC50 values as low as 12–18 nM. This potent nanomolar light-triggered activity combined with a lower dark toxicity resulted in 5 having a phototherapeutic index (PI) margin of almost 275. The bpy coligand led to the least amount of dark toxicity of 1, while phen and pqu produced cytotoxic but selective complexes 2 and

Ambiguities in the deduction of rest frame fluctuation spectrums from spectrums computed in moving frames

International Nuclear Information System (INIS)

Fredericks, R.W.; Coroniti, F.V.

1976-01-01

The problem of interpretation of power spectrums computed by Fourier analysis of data time series taken in frames moving with respect to the medium containing the fluctuations is examined. It is found that no unique connection exists between the rest frame power spectrum as a function of scale length and the derived power spectrum as a function 'frequency' computed from the time series data taken in the moving frame. This caused by a complex Doppler-shifting phenomenon that leads to a basically aliased frequency spectrum in the moving frame. Examples of nonuniqueness are given for various types of rest frame density or wave turbulence that lead to the same frequency dependence of the power spectrum computed in the moving frame. This has implications for the past interpretations of power spectrums of density or magnetic field fluctuations from satellites or interplanetary probes

Diclofenac sodium ion exchange resin complex loaded melt cast films for sustained release ocular delivery.

Science.gov (United States)

Adelli, Goutham R; Balguri, Sai Prachetan; Bhagav, Prakash; Raman, Vijayasankar; Majumdar, Soumyajit

2017-11-01

The goal of the present study is to develop polymeric matrix films loaded with a combination of free diclofenac sodium (DFS free ) and DFS:Ion exchange resin complexes (DFS:IR) for immediate and sustained release profiles, respectively. Effect of ratio of DFS and IR on the DFS:IR complexation efficiency was studied using batch processing. DFS:IR complex, DFS free , or a combination of DFS free  +   DFS:IR loaded matrix films were prepared by melt-cast technology. DFS content was 20% w/w in these matrix films. In vitro transcorneal permeability from the film formulations were compared against DFS solution, using a side-by-side diffusion apparatus, over a 6 h period. Ocular disposition of DFS from the solution, films and corresponding suspensions were evaluated in conscious New Zealand albino rabbits, 4 h and 8 h post-topical administration. All in vivo studies were carried out as per the University of Mississippi IACUC approved protocol. Complexation efficiency of DFS:IR was found to be 99% with a 1:1 ratio of DFS:IR. DFS release from DFS:IR suspension and the film were best-fit to a Higuchi model. In vitro transcorneal flux with the DFS free  +   DFS:IR (1:1) (1 + 1) was twice that of only DFS:IR (1:1) film. In vivo, DFS solution and DFS:IR (1:1) suspension formulations were not able to maintain therapeutic DFS levels in the aqueous humor (AH). Both DFS free and DFS free  +   DFS:IR (1:1) (3 + 1) loaded matrix films were able to achieve and maintain high DFS concentrations in the AH, but elimination of DFS from the ocular tissues was much faster with the DFS free formulation. DFS free  +   DFS:IR combination loaded matrix films were able to deliver and maintain therapeutic DFS concentrations in the anterior ocular chamber for up to 8 h. Thus, free drug/IR complex loaded matrix films could be a potential topical ocular delivery platform for achieving immediate and sustained release characteristics.

Lanthanide complexes with pivaloylacetone

International Nuclear Information System (INIS)

Eliseeva, S.V.; Chugarov, N.V.; Kuz'mina, N.P.; Martynenko, L.I.; Nichiporuk, R.V.; Ivanov, S.A.

2003-01-01

Complexes Ln(pa) 3 ·2H 2 O (Ln=La, Gd, Lu, Hpa - pivaloylacetone) are synthesized and investigated by the methods of element, IR spectroscopic and thermal analyses. Behaviour of the complexes during heating in vacuum is compared with such one for acetylacetonates and dipivaloylmethanates. Structure of the complexes in solution is studied by 1 H NMR and MALDI-MS [ru

IR absorption spectrum (4200-3100 cm-1) of H2O and (H2O)2 in CCl4. Estimates of the equilibrium constant and evidence that the atmospheric water absorption continuum is due to the water dimer

International Nuclear Information System (INIS)

Nicolaisen, Flemming M.

2009-01-01

IR absorption spectra, 4200-3100 cm -1 , of water in CCl 4 solutions are presented. It is shown that for saturated solutions significant amounts of water are present as dimer (ca. 2%). The IR spectra of the monomer and dimer are retrieved. The integrated absorption coefficients of the monomer absorption are significantly enhanced relative to the gas phase values. The dimer spectrum consists of 5 bands, of which 4 were expected from data from cold beams and cold matrices. The origin of the 'extra' band is discussed. In addition it is argued that the dimer absorption bands intensities must be enhanced relative to the gas phase values. Based on recent calculations of band strengths, and observed frequency shifts relative to the gas phase, the intensity enhancement factors are estimated as well as the monomer/dimer equilibrium constant in CCl 4 solution at T=296 K (K c =1.29 mol -1 L). It is noted that the observed dimer spectrum has a striking resemblance with the water vapour continuum determined by Burch in 1985 which was recently remeasured by Paynter et al. and it is concluded that the atmospheric water absorption continuum in the investigated spectral region must be due to water dimer. Based on the newly published spectral data a revised value of the gas phase equilibrium constant is suggested (K p =0.035 atm -1 at T=296 K) as well as a value for the standard enthalpy of formation, ΔH 0 =15.4 kJ mol -1 .

Insulin-induced translocation of IR to the nucleus in insulin responsive cells requires a nuclear translocation sequence.

Science.gov (United States)

Kesten, Dov; Horovitz-Fried, Miriam; Brutman-Barazani, Tamar; Sampson, Sanford R

2018-04-01

Insulin binding to its cell surface receptor (IR) activates a cascade of events leading to its biological effects. The Insulin-IR complex is rapidly internalized and then is either recycled back to the plasma membrane or sent to lysosomes for degradation. Although most of the receptor is recycled or degraded, a small amount may escape this pathway and migrate to the nucleus of the cell where it might be important in promulgation of receptor signals. In this study we explored the mechanism by which insulin induces IR translocation to the cell nucleus. Experiments were performed cultured L6 myoblasts, AML liver cells and 3T3-L1 adipocytes. Insulin treatment induced a rapid increase in nuclear IR protein levels within 2 to 5 min. Treatment with WGA, an inhibitor of nuclear import, reduced insulin-induced increases nuclear IR protein; IR was, however, translocated to a perinuclear location. Bioinformatics tools predicted a potential nuclear localization sequence (NLS) on IR. Immunofluorescence staining showed that a point mutation on the predicted NLS blocked insulin-induced IR nuclear translocation. In addition, blockade of nuclear IR activation in isolated nuclei by an IR blocking antibody abrogated insulin-induced increases in IR tyrosine phosphorylation and nuclear PKCδ levels. Furthermore, over expression of mutated IR reduced insulin-induced glucose uptake and PKB phosphorylation. When added to isolated nuclei, insulin induced IR phosphorylation but had no effect on nuclear IR protein levels. These results raise questions regarding the possible role of nuclear IR in IR signaling and insulin resistance. Copyright © 2018 Elsevier B.V. All rights reserved.

Instantaneous response spectrum in seismic testing of nuclear power plant equipment

International Nuclear Information System (INIS)

Morrone, A.

1977-01-01

Seismic response spectra, as used in seismic analyses, give the maximum responses of single degree of freedom oscillators without consideration of the different time in the seismic time history at which each of the maximum responses occur. For response spectrum seismic analysis, the use of time-independent maximum responses is appropriate. The time dependece is considered in a statistical manner, for multi-degree of freedom systems, usually by combining the modal effects by the square root of the sum of the squares. For seismic testing of electrical equipment. IEEE Std. 344-1975 makes use of the response spectrum to define the input motion of the shake table. One of the basic requirements is that the test response spectrum (TRS) that is, the response spectrum produced by the shake table motion, should envelop the required response spectrum (RRS) calculated from the building analysis at the support point of the equipment being tested. This paper presents the concept of instantaneous response spectrum (IRS) as the response of single degree of freedom oscillators at a particular time. It demonstrates that a shake table random motion whose standard TRS envelops the RRS does not necessarily satisfy the enveloping requirement instantaneously. (Auth.)

Building Bridges across the Autism Spectrum

Science.gov (United States)

Boroson, Barbara

2017-01-01

Among the many challenges that students with autism spectrum disorder bring into the learning environment, teachers report one particular difficulty: working with students' parents. As both an autism educator and parent of a child on the spectrum, Barbara Boroson explores some common complexities in parent-teacher relationships. She also offers…

Inhibition of PTP1B Restores IRS1-Mediated Hepatic Insulin Signaling in IRS2-Deficient Mice

Science.gov (United States)

González-Rodríguez, Águeda; Gutierrez, Jose A. Mas; Sanz-González, Silvia; Ros, Manuel; Burks, Deborah J.; Valverde, Ángela M.

2010-01-01

OBJECTIVE Mice with complete deletion of insulin receptor substrate 2 (IRS2) develop hyperglycemia, impaired hepatic insulin signaling, and elevated gluconeogenesis, whereas mice deficient for protein tyrosine phosphatase (PTP)1B display an opposing hepatic phenotype characterized by increased sensitivity to insulin. To define the relationship between these two signaling pathways in the regulation of liver metabolism, we used genetic and pharmacological approaches to study the effects of inhibiting PTP1B on hepatic insulin signaling and expression of gluconeogenic enzymes in IRS2−/− mice. RESEARCH DESIGN AND METHODS We analyzed glucose homeostasis and insulin signaling in liver and isolated hepatocytes from IRS2−/− and IRS2−/−/PTP1B−/− mice. Additionally, hepatic insulin signaling was assessed in control and IRS2−/− mice treated with resveratrol, an antioxidant present in red wine. RESULTS In livers of hyperglycemic IRS2−/− mice, the expression levels of PTP1B and its association with the insulin receptor (IR) were increased. The absence of PTP1B in the double-mutant mice restored hepatic IRS1-mediated phosphatidylinositol (PI) 3-kinase/Akt/Foxo1 signaling. Moreover, resveratrol treatment of hyperglycemic IRS2−/− mice decreased hepatic PTP1B mRNA and inhibited PTP1B activity, thereby restoring IRS1-mediated PI 3-kinase/Akt/Foxo1 signaling and peripheral insulin sensitivity. CONCLUSIONS By regulating the phosphorylation state of IR, PTB1B determines sensitivity to insulin in liver and exerts a unique role in the interplay between IRS1 and IRS2 in the modulation of hepatic insulin action. PMID:20028942

Validation of the thermal code of RadTherm-IR, IR-Workbench, and F-TOM

Science.gov (United States)

Schwenger, Frédéric; Grossmann, Peter; Malaplate, Alain

2009-05-01

System assessment by image simulation requires synthetic scenarios that can be viewed by the device to be simulated. In addition to physical modeling of the camera, a reliable modeling of scene elements is necessary. Software products for modeling of target data in the IR should be capable of (i) predicting surface temperatures of scene elements over a long period of time and (ii) computing sensor views of the scenario. For such applications, FGAN-FOM acquired the software products RadTherm-IR (ThermoAnalytics Inc., Calumet, USA; IR-Workbench (OKTAL-SE, Toulouse, France). Inspection of the accuracy of simulation results by validation is necessary before using these products for applications. In the first step of validation, the performance of both "thermal solvers" was determined through comparison of the computed diurnal surface temperatures of a simple object with the corresponding values from measurements. CUBI is a rather simple geometric object with well known material parameters which makes it suitable for testing and validating object models in IR. It was used in this study as a test body. Comparison of calculated and measured surface temperature values will be presented, together with the results from the FGAN-FOM thermal object code F-TOM. In the second validation step, radiances of the simulated sensor views computed by RadTherm-IR and IR-Workbench will be compared with radiances retrieved from the recorded sensor images taken by the sensor that was simulated. Strengths and weaknesses of the models RadTherm-IR, IR-Workbench and F-TOM will be discussed.

Looking at Art in the IR and UV

Science.gov (United States)

Falco, Charles

2013-03-01

Starting with the very earliest cave paintings art has been created to be viewed by the unaided eye and, until very recently, it wasn't even possible to see it at wavelengths outside the visible spectrum. However, it is now possible to view paintings, sculptures, manuscripts, and other cultural artifacts at wavelengths from the x-ray, through the ultraviolet (UV), to well into the infrared (IR). Further, thanks to recent advances in technology, this is becoming possible with hand-held instruments that can be used in locations that were previously inaccessible to anything but laboratory-scale image capture equipment. But, what can be learned from such ``non-visible'' images? In this talk I will briefly describe the characteristics of high resolution UV and IR imaging systems I developed for this purpose by modifying high resolution digital cameras. The sensitivity of the IR camera makes it possible to obtain images of art ``in situ'' with standard museum lighting, resolving features finer than 0.35 mm on a 1.0x0.67 m painting. I also have used both it and the UV camera in remote locations with battery-powered illumination sources. I will illustrate their capabilities with images of various examples of Western, Asian, and Islamic art in museums on three continents, describing how these images have revealed important new information about the working practices of artists as famous as Jan van Eyck. I also will describe what will be possible for this type of work with new capabilities that could be developed within the next few years. This work is based on a collaboration with David Hockney, and benefitted from image analys research supported by ARO grant W911NF-06-1-0359-P00001.

Synthesis, crystal structure and bioactivity of manganese complexes with asymmetric chiral Schiff base

Science.gov (United States)

Zhang, Enfeng; Wei, Yi; Huang, Fuping; Yu, Qing; Bian, Hedong; Liang, Hong; Lei, Fuhou

2018-03-01

A couple of chiral unsymmtrical Schiff base ligands, (1R,2R) (-)chxn (salH) (naftalH) and (1S,2S) (-)chxn (salH) (naftalH) had been synthesized by the condensation of salicylaldehyde and 2-hydroxy-1-naphthaldehyde with two isomers of (1R,2R)-trans-1,2-cyclohexanediamin and (1S,2S)-trans-1,2-cyclohexanediamin, respectively. At the same time, two manganese complexes have been synthesized and fully characterized by FT-IR spectrum, elemental analyses, single crystal X-ray diffraction. The interaction of the two Mn (III) complexes with bovine serum albumin (BSA) was investigated by spectroscopic techniques. The result reveals that the complexes can strongly quench the intrinsic fluorescence of BSA through a static quenching mechanism. The binding constant and binding mode has been determined. The secondary structure and the amino acid residues microenvironment of BSA change in the presence of these complexes. SOD-like activity and ABTS free radical scavenging ability were also studied. The antioxidant capacity of the compounds showed that the complexes and their corresponding BSA adducts showed some SOD activity. The results of ABTS free radical scavenging showed that the activity of the BSA adduct was more obvious than that of the complex.

Cationic Amphiphilic Tris-Cyclometalated Iridium(III) Complexes Induce Cancer Cell Death via Interaction with Ca2+-Calmodulin Complex.

Science.gov (United States)

Hisamatsu, Yosuke; Suzuki, Nozomi; Masum, Abdullah-Al; Shibuya, Ai; Abe, Ryo; Sato, Akira; Tanuma, Sei-Ichi; Aoki, Shin

2017-02-15

In our previous paper, we reported on the preparation of some cationic amphiphilic Ir complexes (2c, 2d) containing KKGG peptides that induce and detect cell death of Jurkat cells. Mechanistic studies suggest that 2c interacts with anionic molecules and/or membrane receptors on the cell surface to trigger an intracellular Ca 2+ response, resulting in the induction of cell death, accompanied by membrane disruption. We have continued the studies of cell death of Jurkat cells induced by 2c and found that xestospongin C, a selective inhibitor of an inositol 1,4,5-trisphosphate receptor located on the endoplasmic reticulum (ER), reduces the cytotoxicity of 2c, suggesting that 2c triggers the release of Ca 2+ from the ER, leading to an increase in the concentration of cytosolic Ca 2+ , thus inducing cell death. Moreover, we synthesized a series of new amphiphilic cationic Ir complexes 5a-c containing photoreactive 3-trifluoromethyl-3-phenyldiazirine (TFPD) groups, in an attempt to identify the target molecules of 2c. Interestingly, it was discovered that a TFPD group functions as a triplet quencher of Ir complexes. It was also found that 5b is useful as a turn-on phosphorescent probe of acidic proteins such as bovine serum albumin (BSA) (pI = 4.7) and their complexation was confirmed by luminescence titrations and SDS-PAGE of photochemical products between them. These successful results allowed us to carry out photoaffinity labeling of the target biomolecules of 5b (2c and analogues thereof) in Jurkat cells. A proteomic analysis of the products obtained by the photoirradiation of 5b with Jurkat cells suggests that the Ca 2+ -binding protein "calmodulin (CaM)" is one of target proteins of the Ir complexes. Indeed, 5b was found to interact with the Ca 2+ -CaM complex, as evidenced by luminescence titrations and the results of photochemical reactions of 5b with CaM in the presence of Ca 2+ (SDS-PAGE). A plausible mechanism for cell death induced by a cationic amphiphilic Ir

Synthesis, structure and complex forming ability of phosphorylated derivatives of heterocyclic compounds

International Nuclear Information System (INIS)

Babaev, B.N.

2004-01-01

Full text: The derivatives of acids of phosphorus, due to variety of properties, are a subject of numerous researches. Now it is known, that the derivatives of acids of phosphorus apart from insect, neurotoxic, antienzym and other kinds of physiological activity have also complex forming properties. As extra gents of noble metals particularly are analyzed by the derivatives of dithio phosphor of acids although organ phosphorus compounds with one nuclear of sulfur make extraction properties. Therefore, with the purpose of detection of effective extra gents of ions of argentum the phosphorylated derivatives of heterogeneous ring compounds were synthesized: Ph(RO)P(O)Cl + HOCH(CH 3 )CH 2 -R ' -> Ph(RO)P(O)OCH(CH 3 )CH 2 -R ' + HCl. R C 2 H 5 - C 6 H 13 , R ' = a piperidine, morpholine, anabasine Structure of the obtained connections is confirmed by the results IR -, Pm- and mass- spectrometry. In an IR-spectrum O-hexyl-O - [piperidynoisopropyl] phenylphosphonate has lines of absorption bands of the following functional groups (ν, cm -1 ): (P-O-C 5 H 11 ) 990-1000, (P = 0) 1260, (P-C 6 H 5 )1450, (C-N in cycle) 1550. In an IR-spectrum O-pentyl-[anabasinoisopropyl] phenylphosphonate has lines of absorption bands of the following functional groups (ν, cm -1 ): (P-O-C 5 H 11 ) 990-1000, (P = 0) 1250, (P-C 6 H 5 )1450, (C-N in cycle) 1550. In a spectrum PMR about O-pentyl-[morpholyniisopropyl] phenylphosphonate in the field of a weak field (7, 18-7, 29 p.m.) the multiplet about tones of phenyl group is watched. Me tin proton resonate at 4,66 m.d.as multiplet The signals O-CH 2 of protons of morpholinic cycle appear at 3,58 m.d.. 4H) by the way of triplet. The protons N-CH 2 (6H) three methylene groups will derivate a composite multiple at 2, 10-2, 70 m.d.. The signal of metil group's protons (3H) is watched at 1,15m.d.as doublet. Final metal group resonates at 0, 87 p.m. Six of C-CH 2 of groups give a complex signal in the field of 1, 2-1, 8 m.d. The obtained connections

Time-domain SFG spectroscopy using mid-IR pulse shaping: practical and intrinsic advantages.

Science.gov (United States)

Laaser, Jennifer E; Xiong, Wei; Zanni, Martin T

2011-03-24

Sum-frequency generation (SFG) spectroscopy is a ubiquitous tool in the surface sciences. It provides infrared transition frequencies and line shapes that probe the structure and environment of molecules at interfaces. In this article, we apply techniques learned from the multidimensional spectroscopy community to SFG spectroscopy. We implement balanced heterodyne detection to remove scatter and the local oscillator background. Heterodyning also separates the resonant and nonresonant signals by acquiring both the real and imaginary parts of the spectrum. We utilize mid-IR pulse shaping to control the phase and delay of the mid-IR pump pulse. Pulse shaping allows phase cycling for data collection in the rotating frame and additional background subtraction. We also demonstrate time-domain data collection, which is a Fourier transform technique, and has many advantages in signal throughput, frequency resolution, and line shape accuracy over existing frequency domain methods. To demonstrate time-domain SFG spectroscopy, we study an aryl isocyanide on gold, and find that the system has an inhomogeneous structural distribution, in agreement with computational results, but which was not resolved by previous frequency-domain SFG studies. The ability to rapidly and actively manipulate the mid-IR pulse in an SFG pules sequence makes possible new experiments and more accurate spectra. © 2011 American Chemical Society

STATYBINIŲ MEDŽIAGŲ KONKURENCINGUMAS IR TENDENCIJOS

OpenAIRE

Kontrimas, Robertas

2010-01-01

Darbe analizuojamas statybinių medžiagų konkurencingumas, nustatyti statybinių medžiagų konkurencingumą įtakojantys veiksniai ir pateikti pasiūlymai rinkos gerinimui. Pasitvirtino hipotezė, kad statybinių medžiagų paklausą ir kainas įtakoja klientų poreikiai ir jų finansinės galimybės, tačiau pasaulinės krizės įtaka yra labai ženkli,. Atlikta darbuotojų ir pirkėjų apklausa padėjo nustatyti, kokios statybinės medžiagos dažniausiai yra perkamos, kaip klientai ir darbuotojai vertina įmonę ir jos...

The vibrational spectrum of the hydrated alanine-leucine peptide in the amide region from IR experiments and first principles calculations

Science.gov (United States)

Hassan, Irtaza; Donati, Luca; Stensitzki, Till; Keller, Bettina G.; Heyne, Karsten; Imhof, Petra

2018-04-01

We have combined infrared (IR) experiments with molecular dynamics (MD) simulations in solution at finite temperature to analyse the vibrational signature of the small floppy peptide Alanine-Leucine. IR spectra computed from first-principles MD simulations exhibit no distinct differences between conformational clusters of α -helix or β -sheet-like folds with different orientations of the bulky leucine side chain. All computed spectra show two prominent bands, in good agreement with the experiment, that are assigned to the stretch vibrations of the carbonyl and carboxyl group, respectively. Variations in band widths and exact maxima are likely due to small fluctuations in the backbone torsion angles.

Annual incidence rate of schizophrenia and schizophrenia spectrum disorders in a longitudinal population-based cohort study

NARCIS (Netherlands)

Sutterland, Arjen L.; Dieleman, Jeanne; Storosum, Jitschak G.; Voordouw, Bettie A. C.; Kroon, Jojanneke; Veldhuis, Joris; Denys, Damiaan A. J. P.; de Haan, Lieuwe; Sturkenboom, Miriam C. J. M.

2013-01-01

Longitudinal incidence studies of schizophrenia spectrum disorders (SSD) performed in mental health service organizations are prone to confounding factors not found in research performed in the general population. To estimate the incidence rates (IRs) over a 10-year period of SSD (broadly defined)

Development of a method for determination of fatty acid using FT-IR spectroscopy

Directory of Open Access Journals (Sweden)

Dimas Augusto Morozin Zaia

2011-05-01

Full Text Available In the present paper a new methodology has been developed for determination of fatty acids in biological systems using FT-IR spectroscopy. For this method is not necessary chromophore reagent or pre sample preparation. Palmitic acid was chosen as standard, because it is found in several biological systems. The FT-IR spectrum of palmitic acid showed two absorption bands in the region of 2852 and 2920 cm-1 attributed to CH stretching. The results for these bands showed that the Beer-Lambert Law was followed in wide range of concentration of palmitic acid (14 to 257 mmol L-1. Potassium ferricyanide (K3[Fe(CN6] was used as internal standard. Several interferents were tested and only cholesterol, ferric chloride (higher concentration, mixture of amino acids for the band at 2919 cm-1 (higher concentration and triglyceride could be interferent if they appear in high concentration. Thus, this new methodology has advantage to be not expensive and simple.

A two-state computational investigation of methane C--H and ethane C--C oxidative addition to [CpM(PH3)]n+ (M = Co, Rh, Ir; n = 0, 1).

Science.gov (United States)

Petit, Alban; Richard, Philippe; Cacelli, Ivo; Poli, Rinaldo

2006-01-11

Reductive elimination of methane from methyl hydride half-sandwich phosphane complexes of the Group 9 metals has been investigated by DFT calculations on the model system [CpM(PH(3))(CH(3))(H)] (M = Co, Rh, Ir). For each metal, the unsaturated product has a triplet ground state; thus, spin crossover occurs during the reaction. All relevant stationary points on the two potential energy surfaces (PES) and the minimum energy crossing point (MECP) were optimized. Spin crossover occurs very near the sigma-CH(4) complex local minimum for the Co system, whereas the heavier Rh and Ir systems remain in the singlet state until the CH(4) molecule is almost completely expelled from the metal coordination sphere. No local sigma-CH(4) minimum was found for the Ir system. The energetic profiles agree with the nonexistence of the Co(III) methyl hydride complex and with the greater thermal stability of the Ir complex relative to the Rh complex. Reductive elimination of methane from the related oxidized complexes [CpM(PH(3))(CH(3))(H)](+) (M = Rh, Ir) proceeds entirely on the spin doublet PES, because the 15-electron [CpM(PH(3))](+) products have a doublet ground state. This process is thermodynamically favored by about 25 kcal mol(-1) relative to the corresponding neutral system. It is essentially barrierless for the Rh system and has a relatively small barrier (ca. 7.5 kcal mol(-1)) for the Ir system. In both cases, the reaction involves a sigma-CH(4) intermediate. Reductive elimination of ethane from [CpM(PH(3))(CH(3))(2)](+) (M = Rh, Ir) shows a similar thermodynamic profile, but is kinetically quite different from methane elimination from [CpM(PH(3))(CH(3))(H)](+): the reductive elimination barrier is much greater and does not involve a sigma-complex intermediate. The large difference in the calculated activation barriers (ca. 12.0 and ca. 30.5 kcal mol(-1) for the Rh and Ir systems, respectively) agrees with the experimental observation, for related systems, of oxidatively

Investigation of the porphyrine role at the mechanism of radioprotection

International Nuclear Information System (INIS)

Demoukhamedova, S.D.; Alieva, I.N.; Aliev, D.I.

2002-01-01

Full text: To date, it is well known that unfavourable radioecological conditions capable effect on the oxygen transport system in an living organism, particularly, on the conformational state of hemoglobin. Underlying mechanism is more active autoxidation of Hb(O 2 )4 into met-hemoglobin. Decreasing of the oxygen binding to the heme group of protein as a result of modified effect of ionization was observed into peripheral blood of people living on the polluted territory. Porphyrin, the main component of hemoglobin has been showed a wide range radioprotector properties. So, the conformational reorganization of the porphyrin ring plays an important role at the mechanism of hemoglobin functioning. In this report the result of conformational study, quantum-chemical calculations and theoretical calculation of frequencies and intensities of normal oscillations of IR-absorption spectrum of the porphyrin molecule at the NO-binding are presented. Computational program 'LEV' was used in all carried calculations. Due to changes into IR-spectrum of different complexes, the mechanism underlying the ligand bond formation are discussed. The theoretical frequencies of normal oscillations, satisfactorily described the porphyrin experimental IR-spectrum are received. On the base of both obtained normal oscillation forms and potential energy distribution of vibrational coordinates the detailed theoretical interpretation of the porphyrin molecule vibrational spectrum as well as the analysis of the nature of each absorption band the porphyrin molecule IR-spectrum have been carried out. Porphyrin molecule force field analysis has been showed that the ring electron density is irregular. The results of this study may be used at the theoretical calculations of IR-absorption spectrum of different metallo complexes of the porphyrin

Discrimination of Chinese Sauce liquor using FT-IR and two-dimensional correlation IR spectroscopy

Science.gov (United States)

Sun, Su-Qin; Li, Chang-Wen; Wei, Ji-Ping; Zhou, Qun; Noda, Isao

2006-11-01

We applied the three-step IR macro-fingerprint identification method to obtain the IR characteristic fingerprints of so-called Chinese Sauce liquor (Moutai liquor and Kinsly liquor) and a counterfeit Moutai. These fingerprints can be used for the identification and discrimination of similar liquor products. The comparison of their conventional IR spectra, as the first step of identification, shows that the primary difference in Sauce liquor is the intensity of characteristic peaks at 1592 and 1225 cm -1. The comparison of the second derivative IR spectra, as the second step of identification, shows that the characteristic absorption in 1400-1800 cm -1 is substantially different. The comparison of 2D-IR correlation spectra, as the third and final step of identification, can discriminate the liquors from another direction. Furthermore, the method was successfully applied to the discrimination of a counterfeit Moutai from the genuine Sauce liquor. The success of the three-step IR macro-fingerprint identification to provide a rapid and effective method for the identification of Chinese liquor suggests the potential extension of this technique to the identification and discrimination of other wine and spirits, as well.

Spectroelectrochemical study of polyphenylene by in situ external reflection FT-IR spectroscopy. Pt. 2

International Nuclear Information System (INIS)

Kvarnstroem, C.; Ivaska, A.

1994-01-01

In situ external reflection FT-IR measurements are performed during cyclic voltammetric scans on electrochemically polymerized polyphenylene films. The films are polymerized either in 0.1 or 0.8 M biphenyl in 0.1 M TBABF 4 in acetonitrile. Changes in the IR spectrum of films of different thicknesses are studied when the films are potentially cycled from the neutral to the oxidized states of the polymer. No differences between films made in high or low dimer concentration can be observed in the spectra. The potential-dependent insertion and expulsion of solvent, residual water, anions and cations in and out of the film have different behaviour in films of different thicknesses. Changes in the structure of the segments in the film, from the benzenoid form into the quinoid form, can be followed. Differences between the first and subsequent cyclic potential scans are observed. (orig.)

The HCClF_2-HCCH Complex: Microwave Spectrum, Structure and C-H\\cdotsπ Interactions

Science.gov (United States)

Peebles, Rebecca A.; Sexton, John M.; Elliott, Ashley A.; Steber, Amanda L.; Peebles, Sean A.; Neill, Justin L.; Muckle, Matt T.; Pate, Brooks H.

2010-06-01

The HCF_3-HCCH complex was recently found to have a weak C-H\\cdotsπ interaction between the fluoroform and acetylene, as well as having a secondary interaction between the fluorine atoms and one of the acetylene hydrogen atoms; however, extensive splittings due to large amplitude motions within the complex have complicated our efforts at making a full assignment of the HCF_3-HCCH spectrum. In an attempt to remove some of the ambiguity in the HCF_3-HCCH study, we have substituted a chlorine atom for one fluorine atom and undertaken an investigation of the HCClF_2-HCCH complex. This eliminates the possibility of internal rotation of the methane subunit, while still maintaining a C-H\\cdotsπ interaction. Using the chirped-pulse Fourier-transform microwave (CP-FTMW) spectrometer at the University of Virginia and the Balle-Flygare FTMW spectrometer at Eastern Illinois University, the spectra of four isotopologues of HCClF_2-HCCH have been assigned, with no indication of internal motions within the complex. The structure has been determined from the experimental moments of inertia, confirming that this dimer has the expected weak C-H\\cdotsπ interaction. In addition, the off-diagonal χab quadrupole coupling constant has been used to determine the angle between the C-Cl bond and the a-axis of the complex. This, and Kraitchman coordinates for the chlorine atom, help confirm the structural details from the inertial fit. The structural results will be compared with other complexes showing C-H\\cdotsπ and C-H\\cdotsO interactions. S. A. Peebles, M. M. Serafin, R. A. Peebles, 61st International Symposium on Molecular Spectroscopy, Talk MH13, June 19, 2006.

Enhancement of antibacterial activity of ciprofloxacin hydrochloride by complexation with sodium cholate

Directory of Open Access Journals (Sweden)

Uduma E. Osonwa

2017-12-01

Full Text Available Ciprofloxacin is a broad spectrum bactericidal anti-infective agent of the fluoroquinolones class used in treatment of many bacterial infections. In recent times, there has been increasing resistance to the antibiotic. In this work, we investigated the effect of making an ion- pair complex of Ciprofloxacin – hydrochloride with Sodium cholate on bacterial activity. The optimal ratio of the reactants and pH were determined using UV spectrometry. The complex was characterized by octanol-water partitioning, melting point, and IR spectrometry. The antibacterial activity of the complex was determined against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Streptococcus pneumoniae by the agar-well diffusion method. The complex was whitish to off-white in color and crystalline, with a melting point of 238 °C. The stoichiometry of the complex shows a molar ratio of 1:1 of sodium cholate to ciprofloxacin. The best pH for complexation was pH 9. The complex partitioned 3.38 times into octanol than in water. The FTIR revealed interaction between the 4-nitrogen atom in the 7-piperazinyl group of ciprofloxacin and the carbonyl of the cholate. The drug in complex form gave double the antibacterial activity of the uncomplexed drug. This study showed that development of hydrophobic ion pair complex enhances antibacterial activity of ciprofloxacin hydrochloride. Keywords: Ciprofloxacin, Sodium cholate, Ion-pair complex, Antibacterial activity, Enhanced activity

Frequency notching applicable to CMOS implementation of WLAN compatible IR-UWB pulse generators

DEFF Research Database (Denmark)

Shen, Ming; Mikkelsen, Jan H.; Jiang, Hao

2012-01-01

Due to overlapping frequency bands, IEEE 802.11a WLAN and Ultra Wide-Band systems potentially suffer from mutual interference problems. This paper proposes a method for inserting frequency notches into the IR-UWB power spectrum to ensure compatibility with WLAN systems. In contrast to conventional...... approaches where complicated waveform equations are used, the proposed method uses a dual-pulse frequency notching approach to achieve frequency suppression in selected bands. The proposed method offers a solution that is generically applicable to UWB pulse generators using different pulse waveforms...

The most reactive third-row transition metal: Guided ion beam and theoretical studies of the activation of methane by Ir+

Science.gov (United States)

Li, Feng-Xia; Zhang, Xiao-Guang; Armentrout, P. B.

2006-09-01

The potential energy surface for activation of methane by the third-row transition metal cation, Ir+, is studied experimentally by examining the kinetic energy dependence of reactions of Ir+ with methane, IrCH2+ with H2 and D2, and collision-induced dissociation of IrCH2+ with Xe using guided ion beam tandem mass spectrometry. A flow tube ion source produces Ir+ in its electronic ground state term and primarily in the ground spin-orbit level. We find that dehydrogenation to form IrCH2+ + H2 is exothermic, efficient, and the only process observed at low energies for reaction of Ir+ with methane, whereas IrH+ dominates the product spectrum at higher energies. We also observe the IrH2+ product, which provides evidence that methane activation proceeds via a dihydride (H)2IrCH2+ intermediate. The kinetic energy dependences of the cross sections for several endothermic reactions are analyzed to give 0 K bond dissociation energies (in eV) of D0(Ir+-2H) > 5.09 +/- 0.07, D0(Ir+-C) = 6.59 +/- 0.05, D0(Ir+-CH) = 6.91 +/- 0.23, and D0(Ir+-CH3) = 3.25 +/- 0.18. D0(Ir+-CH2) = 4.92 +/- 0.03 eV is determined by measuring the forward and reverse reaction rates for Ir++CH4[right harpoon over left]IrCH2++H2 at thermal energy. Ab initio calculations at the B3LYP/HW+/6-311++G(3df,3p) level performed here show reasonable agreement with the experimental bond energies and with the few previous experimental and theoretical values available. Theory also provides the electronic structures of the product species as well as intermediates and transition states along the reactive potential energy surfaces. We also compare this third-row transition metal system with the first-row and second-row congeners, Co+ and Rh+. Differences in reactivity and mechanisms can be explained by the lanthanide contraction and relativistic effects that alter the relative size of the valence s and d orbitals.

The Introduction of an Undergraduate Interventional Radiology (IR) Curriculum: Impact on Medical Student Knowledge and Interest in IR

International Nuclear Information System (INIS)

Shaikh, M.; Shaygi, B.; Asadi, H.; Thanaratnam, P.; Pennycooke, K.; Mirza, M.; Lee, M.

2016-01-01

IntroductionInterventional radiology (IR) plays a vital role in modern medicine, with increasing demand for services, but with a shortage of experienced interventionalists. The aim of this study was to determine the impact of a recently introduced IR curriculum on perception, knowledge, and interest of medical students regarding various aspects of IR.MethodsIn 2014, an anonymous web-based questionnaire was sent to 309 4th year medical students in a single institution within an EU country, both before and after delivery of a 10-h IR teaching curriculum.ResultsSeventy-six percent (236/309) of the respondents participated in the pre-IR module survey, while 50 % (157/309) responded to the post-IR module survey. While 62 % (147/236) of the respondents reported poor or no knowledge of IR compared to other medical disciplines in the pre-IR module survey, this decreased to 17 % (27/157) in the post-IR module survey. The correct responses regarding knowledge of selected IR procedures improved from 70 to 94 % for venous access, 78 to 99 % for uterine fibroid embolization, 75 to 97 % for GI bleeding embolization, 60 to 92 % for trauma embolization, 71 to 92 % for tumor ablation, and 81 to 94 % for angioplasty and stenting in peripheral arterial disease. With regard to knowledge of IR clinical roles, responses improved from 42 to 59 % for outpatient clinic review of patients and having inpatient beds, 63–76 % for direct patient consultation, and 43–60 % for having regular ward rounds. The number of students who would consider a career in IR increased from 60 to 73 %.ConclusionDelivering an undergraduate IR curriculum increased the knowledge and understanding of various aspects of IR and also the general enthusiasm for pursuing this specialty as a future career choice.

The Introduction of an Undergraduate Interventional Radiology (IR) Curriculum: Impact on Medical Student Knowledge and Interest in IR

Energy Technology Data Exchange (ETDEWEB)

Shaikh, M. [Bradford Royal Infirmary, Department of Radiology, Bradford Teaching Hospital Foundation Trust (United Kingdom); Shaygi, B. [Royal Devon and Exeter Hospital, Interventional Radiology Department (United Kingdom); Asadi, H., E-mail: asadi.hamed@gmail.com; Thanaratnam, P.; Pennycooke, K.; Mirza, M.; Lee, M., E-mail: mlee@rcsi.ie [Beaumont Hospital, Interventional Radiology Service, Department of Radiology (Ireland)

2016-04-15

IntroductionInterventional radiology (IR) plays a vital role in modern medicine, with increasing demand for services, but with a shortage of experienced interventionalists. The aim of this study was to determine the impact of a recently introduced IR curriculum on perception, knowledge, and interest of medical students regarding various aspects of IR.MethodsIn 2014, an anonymous web-based questionnaire was sent to 309 4th year medical students in a single institution within an EU country, both before and after delivery of a 10-h IR teaching curriculum.ResultsSeventy-six percent (236/309) of the respondents participated in the pre-IR module survey, while 50 % (157/309) responded to the post-IR module survey. While 62 % (147/236) of the respondents reported poor or no knowledge of IR compared to other medical disciplines in the pre-IR module survey, this decreased to 17 % (27/157) in the post-IR module survey. The correct responses regarding knowledge of selected IR procedures improved from 70 to 94 % for venous access, 78 to 99 % for uterine fibroid embolization, 75 to 97 % for GI bleeding embolization, 60 to 92 % for trauma embolization, 71 to 92 % for tumor ablation, and 81 to 94 % for angioplasty and stenting in peripheral arterial disease. With regard to knowledge of IR clinical roles, responses improved from 42 to 59 % for outpatient clinic review of patients and having inpatient beds, 63–76 % for direct patient consultation, and 43–60 % for having regular ward rounds. The number of students who would consider a career in IR increased from 60 to 73 %.ConclusionDelivering an undergraduate IR curriculum increased the knowledge and understanding of various aspects of IR and also the general enthusiasm for pursuing this specialty as a future career choice.

Ion beam synthesis of IrSi3 by implantation of 2 MeV Ir ions

International Nuclear Information System (INIS)

Sjoreen, T.P.; Chisholm, M.F.; Hinneberg, H.J.

1992-11-01

Formation of a buried IrSi 3 layer in (111) oriented Si by ion implantation and annealing has been studied at an implantation energy of 2 MeV for substrate temperatures of 450--550C. Rutherford backscattering (RBS), ion channeling and cross-sectional transmission electron microscopy showed that a buried epitaxial IrSi 3 layer is produced at 550C by implanting ≥ 3.4 x 10 17 Ir/cm 2 and subsequently annealing for 1 h at 1000C plus 5 h at 1100C. At a dose of 3.4 x 10 17 Ir/cm 2 , the thickness of the layer varied between 120 and 190 nm and many large IrSi 3 precipitates were present above and below the film. Increasing the dose to 4.4 x 10 17 Ir/cm 2 improved the layer uniformity at the expense of increased lattice damage in the overlying Si. RBS analysis of layer formation as a function of substrate temperature revealed the competition between the mechanisms for optimizing surface crystallinity vs. IrSi 3 layer formation. Little apparent substrate temperature dependence was evident in the as-implanted state but after annealing the crystallinity of the top Si layer was observed to deteriorate with increasing substrate temperature while the precipitate coarsening and coalescence improved

Interactive information seeking, behaviour and retrieval

CERN Document Server

Ruthven, Ian

2011-01-01

Information retrieval (IR) is a complex human activity supported by sophisticated systems. This book covers the whole spectrum of information retrieval, including: history and background information; behaviour and seeking task-based information; searching and retrieval approaches to investigating information; and, evaluation interfaces for IR.

IR Spectroscopy of Ethylene Glycol Solutions of Dimethylsulfoxide

Science.gov (United States)

Kononova, E. G.; Rodnikova, M. N.; Solonina, I. A.; Sirotkin, D. A.

2018-07-01

Features of ethylene glycol (EG) solutions of dimethylsulfoxide (DMSO) with low and moderate concentrations (from 2 to 50 mol % of DMSO) are studied by IR spectroscopy on a Bruker Tensor 37 FT-IR spectrometer in the wavenumber range of 400 to 4000 cm-1. The main monitored bands are the S=O stretching vibration band of DMSO (1057 cm-1) and the C-O (1086 and 1041 cm-1) and O-H (3350 cm-1) stretching vibration bands of EG. The obtained data show complex DMSO · 2EG to be present in all solutions with the studied concentrations due to formation of H-bonds between the S=O group of DMSO and the OH group of EG. In the concentration range of 6 to 25 mol % DMSO, the OH stretching vibration of EG is found to be broadened (by up to 70 cm-1), suggesting the strengthening of hydrogen bonds in the spatial network of the system due to the solvophobic effect of DMSO molecules and the formation of DMSO · 2EG. Starting from 25 mol % DMSO, narrowing of the OH stretching vibration is noted, and the bands of free DMSO appear along with the DMSO · 2EG complex, suggesting microseparation in the investigated system. At 50 mol % DMSO, the amounts of free and bound species in the system became comparable.

Smulkaus ir vidutinio verslo konkurencingumas Lietuvoje

OpenAIRE

Vijeikis, Juozas; Makštutis, Antanas

2009-01-01

Straipsnio mokslinė problema, naujumas ir aktualumas. Konkurencingumas kaip įmonių efektyvios veiklos reiškinys yra aktualus šalies verslo gyvenime vykdant darnios ekonominės plėtros politiką. Ši politika kaip problema smulkaus ir vidutinio verslo (SVV) plėtrai ir konkurencingumui didinti nėra sistemiškai ištirta ir aprašyta Lietuvos sąlygomis mokslinėje ir praktinėje literatūroje. Vienas svarbiausių veiksnių, siekiant spartaus ekonominio augimo, yra darnios verslininkystės plėtra Lietuvoje n...

Structural, phase stability, electronic, elastic properties and hardness of IrN{sub 2} and zinc blende IrN: First-principles calculations

Energy Technology Data Exchange (ETDEWEB)

Zhou, Zhaobo [Key Laboratory of Advanced Materials of Yunnan Province & Key Laboratory of Advanced Materials of Non-Ferrous and Precious Rare Metals Ministry of Education, Kunming University of Science and Technology, Kunming 650093 (China); Zhou, Xiaolong, E-mail: kmzxlong@163.com [Key Laboratory of Advanced Materials of Yunnan Province & Key Laboratory of Advanced Materials of Non-Ferrous and Precious Rare Metals Ministry of Education, Kunming University of Science and Technology, Kunming 650093 (China); Zhang, Kunhua [State Key Laboratory of Rare Precious Metals Comprehensive Utilization of New Technologies, Kunming Institute of Precious Metals, Kunming 650106 (China)

2016-12-15

First-principle calculations were performed to investigate the structural, phase stability, electronic, elastic properties and hardness of monoclinic structure IrN{sub 2} (m-IrN{sub 2}), orthorhombic structure IrN{sub 2} (o-IrN{sub 2}) and zinc blende structure IrN (ZB IrN). The results show us that only m-IrN{sub 2} is both thermodynamic and dynamic stability. The calculated band structure and density of states (DOS) curves indicate that o-IrN{sub 2} and ZB Ir-N compounds we calculated have metallic behavior while m-IrN{sub 2} has a small band gap of ~0.3 eV, and exist a common hybridization between Ir-5d and N-2p states, which forming covalent bonding between Ir and N atoms. The difference charge density reveals the electron transfer from Ir atom to N atom for three Ir-N compounds, which forming strong directional covalent bonds. Notable, a strong N-N bond appeared in m-IrN{sub 2} and o-IrN{sub 2}. The ratio of bulk to shear modulus (B/G) indicate that three Ir-N compounds we calculated are ductile, and ZB IrN possesses a better ductility than two types IrN{sub 2}. m-IrN{sub 2} has highest Debye temperature (736 K), illustrating it possesses strongest covalent bonding. The hardness of three Ir-N compounds were also calculated, and the results reveal that m-IrN{sub 2} (18.23 GPa) and o-IrN{sub 2} (18.02 GPa) are ultraincompressible while ZB IrN has a negative value, which may be attributed to phase transition at ca. 1.98 GPa.

Probing Gas Adsorption in Zeolites by Variable-Temperature IR Spectroscopy: An Overview of Current Research.

Science.gov (United States)

Garrone, Edoardo; Delgado, Montserrat R; Bonelli, Barbara; Arean, Carlos O

2017-09-15

The current state of the art in the application of variable-temperature IR (VTIR) spectroscopy to the study of (i) adsorption sites in zeolites, including dual cation sites; (ii) the structure of adsorption complexes and (iii) gas-solid interaction energy is reviewed. The main focus is placed on the potential use of zeolites for gas separation, purification and transport, but possible extension to the field of heterogeneous catalysis is also envisaged. A critical comparison with classical IR spectroscopy and adsorption calorimetry shows that the main merits of VTIR spectroscopy are (i) its ability to provide simultaneously the spectroscopic signature of the adsorption complex and the standard enthalpy change involved in the adsorption process; and (ii) the enhanced potential of VTIR to be site specific in favorable cases.

Combustion-related studies using weakly-bonded complexes

Energy Technology Data Exchange (ETDEWEB)

Beaudet, R.A. [Univ. of Southern California, Los Angeles (United States)

1993-12-01

Binary van der Waals complexes involving species of interest to combustion research are prepared in supersonic free-jet expansions, and their photochemical and photophysical properties are probed by using IR tunable diode laser (TDL) spectroscopy. In the first phase, geometries and other molecular properties are being determined from vibration-rotational spectra. In the second phase, these complexes will be used as precursors to study photoinitiated reactions in precursor geometry limited environments. Two complementary classes of binary complexes are being investigated. The first involves molecular oxygen and hydrogen containing constituents (e.g. O{sub 2}-HCN, O{sub 2}-HF, O{sub 2}-HCl, O{sub 2}-HBr, O{sub 2}-HI and O{sub 2}-hydrocarbons). These species are interesting candidates for study since upon photodissociating the hydride portion, the reaction H and O{sub 2} via the vibrationally excited HO{sub 2} intermediate can conceivably be studied, (e.g. BrH-O{sub 2} + hv(193 nm) {yields} Br-H-O{sub 2} {yields} Br + HO{sub 2} {yields} Br + OH + O). High resolution IR spectroscopy of such complexes have not been obtained previously and the structural information deriving from IR spectra is certainly very useful for better designing and understanding photoinitiated reactions that occur in these complexes.

2D IR spectra of cyanide in water investigated by molecular dynamics simulations

Science.gov (United States)

Lee, Myung Won; Carr, Joshua K.; Göllner, Michael; Hamm, Peter; Meuwly, Markus

2013-01-01

Using classical molecular dynamics simulations, the 2D infrared (IR) spectroscopy of CN− solvated in D2O is investigated. Depending on the force field parametrizations, most of which are based on multipolar interactions for the CN− molecule, the frequency-frequency correlation function and observables computed from it differ. Most notably, models based on multipoles for CN− and TIP3P for water yield quantitatively correct results when compared with experiments. Furthermore, the recent finding that T 1 times are sensitive to the van der Waals ranges on the CN− is confirmed in the present study. For the linear IR spectrum, the best model reproduces the full widths at half maximum almost quantitatively (13.0 cm−1 vs. 14.9 cm−1) if the rotational contribution to the linewidth is included. Without the rotational contribution, the lines are too narrow by about a factor of two, which agrees with Raman and IR experiments. The computed and experimental tilt angles (or nodal slopes) α as a function of the 2D IR waiting time compare favorably with the measured ones and the frequency fluctuation correlation function is invariably found to contain three time scales: a sub-ps, 1 ps, and one on the 10-ps time scale. These time scales are discussed in terms of the structural dynamics of the surrounding solvent and it is found that the longest time scale (≈10 ps) most likely corresponds to solvent exchange between the first and second solvation shell, in agreement with interpretations from nuclear magnetic resonance measurements.

Improved designs of Si-based quantum wells and Schottky diodes for IR detection

Energy Technology Data Exchange (ETDEWEB)

Moeen, M., E-mail: moeen@kth.se [School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, 16640, Kista (Sweden); Kolahdouz, M. [School of Electrical and Computer Engineering, University of Tehran, Tehran (Iran, Islamic Republic of); Salemi, A.; Abedin, A.; Östling, M. [School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, 16640, Kista (Sweden); Radamson, H.H., E-mail: rad@kth.se [School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, 16640, Kista (Sweden)

2016-08-31

Novel structures of intrinsic or carbon-doped multi quantum wells (MQWs) and intrinsic or carbon-doped Si Schottky diodes (SD), individually or in combination, have been manufactured to detect the infrared (IR) radiation. The carbon concentration in the structures was 5 × 10{sup 20} cm{sup −3} and the MQWs are located in the active part of the IR detector. A Schottky diode was designed and formed as one of the contacts (based on NiSi(C)/TiW) to MQWs where on the other side the structure had an Ohmic contact. The thermal response of the detectors is expressed in terms of temperature coefficient of resistance (TCR) and the quality of the electrical signal is quantified by the signal-to-noise ratio. The noise measurements provide the K{sub 1/f} parameter which is obtained from the power spectrum density. An excellent value of TCR = − 6%/K and K{sub 1/f} = 4.7 × 10{sup −14} was measured for the detectors which consist of the MQWs in series with the SD. These outstanding electrical results indicate a good opportunity to manufacture low cost Si-based IR detectors in the near future. - Highlights: • SiGe (C)/Si(C) multi quantum wells (MQWs) are evaluated to detect IR radiation. • Schottky diodes (SDs), individually or in series with MQWs are also fabricated. • Detectors consisted of MQWs in series with SD show excellent thermal sensing. • The noise values are also extremely low for MQWs in series with SD.

Improved designs of Si-based quantum wells and Schottky diodes for IR detection

International Nuclear Information System (INIS)

Moeen, M.; Kolahdouz, M.; Salemi, A.; Abedin, A.; Östling, M.; Radamson, H.H.

2016-01-01

Novel structures of intrinsic or carbon-doped multi quantum wells (MQWs) and intrinsic or carbon-doped Si Schottky diodes (SD), individually or in combination, have been manufactured to detect the infrared (IR) radiation. The carbon concentration in the structures was 5 × 10 20 cm −3 and the MQWs are located in the active part of the IR detector. A Schottky diode was designed and formed as one of the contacts (based on NiSi(C)/TiW) to MQWs where on the other side the structure had an Ohmic contact. The thermal response of the detectors is expressed in terms of temperature coefficient of resistance (TCR) and the quality of the electrical signal is quantified by the signal-to-noise ratio. The noise measurements provide the K 1/f parameter which is obtained from the power spectrum density. An excellent value of TCR = − 6%/K and K 1/f = 4.7 × 10 −14 was measured for the detectors which consist of the MQWs in series with the SD. These outstanding electrical results indicate a good opportunity to manufacture low cost Si-based IR detectors in the near future. - Highlights: • SiGe (C)/Si(C) multi quantum wells (MQWs) are evaluated to detect IR radiation. • Schottky diodes (SDs), individually or in series with MQWs are also fabricated. • Detectors consisted of MQWs in series with SD show excellent thermal sensing. • The noise values are also extremely low for MQWs in series with SD.

Rapid, nondestructive estimation of surface polymer layer thickness using attenuated total reflection fourier transform infrared (ATR FT-IR) spectroscopy and synthetic spectra derived from optical principles.

Science.gov (United States)

Weinstock, B André; Guiney, Linda M; Loose, Christopher

2012-11-01

We have developed a rapid, nondestructive analytical method that estimates the thickness of a surface polymer layer with high precision but unknown accuracy using a single attenuated total reflection Fourier transform infrared (ATR FT-IR) measurement. Because the method is rapid, nondestructive, and requires no sample preparation, it is ideal as a process analytical technique. Prior to implementation, the ATR FT-IR spectrum of the substrate layer pure component and the ATR FT-IR and real refractive index spectra of the surface layer pure component must be known. From these three input spectra a synthetic mid-infrared spectral matrix of surface layers 0 nm to 10,000 nm thick on substrate is created de novo. A minimum statistical distance match between a process sample's ATR FT-IR spectrum and the synthetic spectral matrix provides the thickness of that sample. We show that this method can be used to successfully estimate the thickness of polysulfobetaine surface modification, a hydrated polymeric surface layer covalently bonded onto a polyetherurethane substrate. A database of 1850 sample spectra was examined. Spectrochemical matrix-effect unknowns, such as the nonuniform and molecularly novel polysulfobetaine-polyetherurethane interface, were found to be minimal. A partial least squares regression analysis of the database spectra versus their thicknesses as calculated by the method described yielded an estimate of precision of ±52 nm.

Protection of p+-n-Si Photoanodes by Sputter-Deposited Ir/IrOxThin Films

DEFF Research Database (Denmark)

Mei, Bastian Timo; Seger, Brian; Pedersen, Thomas

2014-01-01

Sputter deposition of Ir/IrOx on p+-n-Si without interfacial corrosion protection layers yielded photoanodes capable of efficient water oxidation (OER) in acidic media (1 M H2SO4). Stability of at least 18 h was shown by chronoamperomety at 1.23 V versus RHE (reversible hydrogen electrode) under 38...... density of 1 mA/cm2 at 1.05 V vs. RHE. Further improvement by heat treatment resulted in a cathodic shift of 40 mV and enabled a current density of 10 mA/cm2 (requirements for a 10% efficient tandem device) at 1.12 V vs. RHS under irradiation. Thus, the simple IrOx/Ir/p+-n-Si structures not only provide...

Novel cross-talk between IGF-IR and DDR1 regulates IGF-IR trafficking, signaling and biological responses

Science.gov (United States)

Sacco, Antonella; Morcavallo, Alaide; Vella, Veronica; Voci, Concetta; Spatuzza, Michela; Xu, Shi-Qiong; Iozzo, Renato V.; Vigneri, Riccardo; Morrione, Andrea; Belfiore, Antonino

2015-01-01

The insulin-like growth factor-I receptor (IGF-IR), plays a key role in regulating mammalian development and growth, and is frequently deregulated in cancer contributing to tumor initiation and progression. Discoidin domain receptor 1 (DDR1), a collagen receptor tyrosine-kinase, is as well frequently overexpressed in cancer and implicated in cancer progression. Thus, we investigated whether a functional cross-talk between the IGF-IR and DDR1 exists and plays any role in cancer progression. Using human breast cancer cells we found that DDR1 constitutively associated with the IGF-IR. However, this interaction was enhanced by IGF-I stimulation, which promoted rapid DDR1 tyrosine-phosphorylation and co-internalization with the IGF-IR. Significantly, DDR1 was critical for IGF-IR endocytosis and trafficking into early endosomes, IGF-IR protein expression and IGF-I intracellular signaling and biological effects, including cell proliferation, migration and colony formation. These biological responses were inhibited by DDR1 silencing and enhanced by DDR1 overexpression. Experiments in mouse fibroblasts co-transfected with the human IGF-IR and DDR1 gave similar results and indicated that, in the absence of IGF-IR, collagen-dependent phosphorylation of DDR1 is impaired. These results demonstrate a critical role of DDR1 in the regulation of IGF-IR action, and identify DDR1 as a novel important target for breast cancers that overexpress IGF-IR. PMID:25840417

Context processing in adolescents with autism spectrum disorder: How complex could it be?

Science.gov (United States)

Ben-Yosef, Dekel; Anaki, David; Golan, Ofer

2017-03-01

The ability of individuals with Autism Spectrum Disorder (ASD) to process context has long been debated: According to the Weak Central Coherence theory, ASD is characterized by poor global processing, and consequently-poor context processing. In contrast, the Social Cognition theory argues individuals with ASD will present difficulties only in social context processing. The complexity theory of autism suggests context processing in ASD will depend on task complexity. The current study examined this controversy through two priming tasks, one presenting human stimuli (facial expressions) and the other presenting non-human stimuli (animal faces). Both tasks presented visual targets, preceded by congruent, incongruent, or neutral auditory primes. Local and global processing were examined by presenting the visual targets in three spatial frequency conditions: High frequency, low frequency, and broadband. Tasks were administered to 16 adolescents with high functioning ASD and 16 matched typically developing adolescents. Reaction time and accuracy were measured for each task in each condition. Results indicated that individuals with ASD processed context for both human and non-human stimuli, except in one condition, in which human stimuli had to be processed globally (i.e., target presented in low frequency). The task demands presented in this condition, and the performance deficit shown in the ASD group as a result, could be understood in terms of cognitive overload. These findings provide support for the complexity theory of autism and extend it. Our results also demonstrate how associative priming could support intact context processing of human and non-human stimuli in individuals with ASD. Autism Res 2017, 10: 520-530. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Coexistence of Autism Spectrum Disorders Among Three Children with Tuberous Sclerosis Complex; Case reports and review of literature

Directory of Open Access Journals (Sweden)

Amna Al-Futaisi

2016-11-01

Full Text Available Tuberous sclerosis complex (TSC is a multisystem neurocutaneous disorder inherited in an autosomal dominant manner and characterised by benign tumours in the brain and other vital organs such as the heart, eyes, kidneys, skin and lungs. Links between autism spectrum disorder (ASD and TSC have been postulated for many decades, with TSC considered to be one of the main syndromic causes of ASD; however, precise confirmation of a relationship between these two disorders required validated diagnostic tools. Fortunately, accurate evaluation of this relationship is now possible with standardised criteria for ASD diagnosis. We report three children who presented to the Sultan Qaboos University Hospital, Muscat, Oman, between 2014 and 2015 with ASD and TSC. These cases demonstrate the spectrum of neuropsychiatric involvement in TSC and highlight the importance of screening children with TSC for ASD features in order to encourage the early enrolment of these children in educational and rehabilitation programmes.

HOMA1-IR and HOMA2-IR indexes in identifying insulin resistance and metabolic syndrome: Brazilian Metabolic Syndrome Study (BRAMS).

Science.gov (United States)

Geloneze, Bruno; Vasques, Ana Carolina Junqueira; Stabe, Christiane França Camargo; Pareja, José Carlos; Rosado, Lina Enriqueta Frandsen Paez de Lima; Queiroz, Elaine Cristina de; Tambascia, Marcos Antonio

2009-03-01

To investigate cut-off values for HOMA1-IR and HOMA2-IR to identify insulin resistance (IR) and metabolic syndrome (MS), and to assess the association of the indexes with components of the MS. Nondiabetic subjects from the Brazilian Metabolic Syndrome Study were studied (n = 1,203, 18 to 78 years). The cut-off values for IR were determined from the 90th percentile in the healthy group (n = 297) and, for MS, a ROC curve was generated for the total sample. In the healthy group, HOMA-IR indexes were associated with central obesity, triglycerides and total cholesterol (p 2.7 and HOMA2-IR > 1.8; and, for MS were: HOMA1-IR > 2.3 (sensitivity: 76.8%; specificity: 66.7%) and HOMA2-IR > 1.4 (sensitivity: 79.2%; specificity: 61.2%). The cut-off values identified for HOMA1-IR and HOMA2-IR indexes have a clinical and epidemiological application for identifying IR and MS in Westernized admixtured multi-ethnic populations.

IOT Overview: IR Instruments

Science.gov (United States)

Mason, E.

In this instrument review chapter the calibration plans of ESO IR instruments are presented and briefly reviewed focusing, in particular, on the case of ISAAC, which has been the first IR instrument at VLT and whose calibration plan served as prototype for the coming instruments.

Atom condensation on an atomically smooth surface: Ir, Re, W, and Pd on Ir(111)

International Nuclear Information System (INIS)

Wang, S.C.; Ehrlich, G.

1991-01-01

The distribution of condensing metal atoms over the two types of sites present on an atomically smooth Ir(111) has been measured in a field ion microscope. For Ir, Re, W, and Pd from a thermal source, condensing on Ir(111) at ∼20 K, the atoms are randomly distributed, as expected if they condense at the first site struck

Defining the diverse spectrum of inversions, complex structural variation, and chromothripsis in the morbid human genome.

Science.gov (United States)

Collins, Ryan L; Brand, Harrison; Redin, Claire E; Hanscom, Carrie; Antolik, Caroline; Stone, Matthew R; Glessner, Joseph T; Mason, Tamara; Pregno, Giulia; Dorrani, Naghmeh; Mandrile, Giorgia; Giachino, Daniela; Perrin, Danielle; Walsh, Cole; Cipicchio, Michelle; Costello, Maura; Stortchevoi, Alexei; An, Joon-Yong; Currall, Benjamin B; Seabra, Catarina M; Ragavendran, Ashok; Margolin, Lauren; Martinez-Agosto, Julian A; Lucente, Diane; Levy, Brynn; Sanders, Stephan J; Wapner, Ronald J; Quintero-Rivera, Fabiola; Kloosterman, Wigard; Talkowski, Michael E

2017-03-06

Structural variation (SV) influences genome organization and contributes to human disease. However, the complete mutational spectrum of SV has not been routinely captured in disease association studies. We sequenced 689 participants with autism spectrum disorder (ASD) and other developmental abnormalities to construct a genome-wide map of large SV. Using long-insert jumping libraries at 105X mean physical coverage and linked-read whole-genome sequencing from 10X Genomics, we document seven major SV classes at ~5 kb SV resolution. Our results encompass 11,735 distinct large SV sites, 38.1% of which are novel and 16.8% of which are balanced or complex. We characterize 16 recurrent subclasses of complex SV (cxSV), revealing that: (1) cxSV are larger and rarer than canonical SV; (2) each genome harbors 14 large cxSV on average; (3) 84.4% of large cxSVs involve inversion; and (4) most large cxSV (93.8%) have not been delineated in previous studies. Rare SVs are more likely to disrupt coding and regulatory non-coding loci, particularly when truncating constrained and disease-associated genes. We also identify multiple cases of catastrophic chromosomal rearrangements known as chromoanagenesis, including somatic chromoanasynthesis, and extreme balanced germline chromothripsis events involving up to 65 breakpoints and 60.6 Mb across four chromosomes, further defining rare categories of extreme cxSV. These data provide a foundational map of large SV in the morbid human genome and demonstrate a previously underappreciated abundance and diversity of cxSV that should be considered in genomic studies of human disease.

Suppression of superconductivity in Nb by IrMn in IrMn/Nb bilayers

KAUST Repository

Wu, B. L.; Yang, Y. M.; Guo, Z. B.; Wu, Y. H.; Qiu, J. J.

2013-01-01

Effect of antiferromagnet on superconductivity has been investigated in IrMn/Nb bilayers. Significant suppression of both transition temperature (Tc) and lower critical field (Hc1) of Nb is found in IrMn/Nb bilayers as compared to a single layer Nb

MTF measurement of IR optics in different temperature ranges

Science.gov (United States)

Bai, Alexander; Duncker, Hannes; Dumitrescu, Eugen

2017-10-01

Infrared (IR) optical systems are at the core of many military, civilian and manufacturing applications and perform mission critical functions. To reliably fulfill the demanding requirements imposed on today's high performance IR optics, highly accurate, reproducible and fast lens testing is of crucial importance. Testing the optical performance within different temperature ranges becomes key in many military applications. Due to highly complex IR-Applications in the fields of aerospace, military and automotive industries, MTF Measurement under realistic environmental conditions become more and more relevant. A Modulation Transfer Function (MTF) test bench with an integrated thermal chamber allows measuring several sample sizes in a temperature range from -40 °C to +120°C. To reach reliable measurement results under these difficult conditions, a specially developed temperature stable design including an insulating vacuum are used. The main function of this instrument is the measurement of the MTF both on- and off-axis at up to +/-70° field angle, as well as measurement of effective focal length, flange focal length and distortion. The vertical configuration of the system guarantees a small overall footprint. By integrating a high-resolution IR camera with focal plane array (FPA) in the detection unit, time consuming measurement procedures such as scanning slit with liquid nitrogen cooled detectors can be avoided. The specified absolute accuracy of +/- 3% MTF is validated using internationally traceable reference optics. Together with a complete and intuitive software solution, this makes the instrument a turn-key device for today's state-of- the-art optical testing.

Probing the spin multiplicity of gas-phase polycyclic aromatic hydrocarbons through their infrared emission spectrum: a theoretical study.

Science.gov (United States)

Falvo, Cyril; Calvo, Florent; Parneix, Pascal

2012-08-14

The anharmonic infrared emission spectrum following an optical excitation has been calculated for a variety of polycyclic aromatic hydrocarbon molecules in their ground singlet electronic state or in their triplet state. The computational protocol relies on second-order perturbation theory and involves a quartic vibrational Hamiltonian, the vibrational quantum numbers being sampled according to a Monte Carlo procedure. In the case of neutral naphthalene, the IR spectrum obtained in the (ground) singlet state differs significantly from the spectrum in the triplet state, especially for out-of-plane CH bending modes. Although not as prominent, spectral differences in larger molecules are still observable.

Exploring the complexity of intellectual disability in fetal alcohol spectrum disorders

Directory of Open Access Journals (Sweden)

Aniruddho eChokroborty-Hoque

2014-08-01

Full Text Available Brain development in mammals is long lasting. It begins early during embryonic growth and is finalized in early adulthood. This progression represents a delicate choreography of molecular, cellular and physiological processes initiated and directed by the fetal genotype in close interaction with environment. Not surprisingly, most aberrations in brain functioning including mental retardation are attributed to either gene(s, or environment or the interaction of the two. The ensuing complexity has made the assessment of this choreography, ever challenging. A model to assess this complexity has used a mouse model (C57BL/6J or B6 that is subjected to prenatal alcohol exposure. The resulting pups show learning and memory deficits similar to patients with fetal alcohol spectrum disorder (FASD, which is associated with life-long changes in gene expression. Interestingly, this change in gene expression underlies epigenetic processes including DNA methylation and miRNAs. This paradigm is applicable to ethanol exposure at different developmental times (binge at trimesters 1, 2 and 3 as well as continuous preference drinking (70% of 10% alcohol by B6 females during pregnancy. The exposure leads to life-long changes in neural epigenetic marks, gene expression, and a variety of defects in neurodevelopment and CNS function. We argue that this cascade may be reversed postnatally via drugs, chemicals and environment including maternal care. Such conclusions are supported by two sets of results. First, antipsychotic drugs that are used to treat mental disability including psychosis function via changes in DNA methylation, a major epigenetic mark. Second, post-natal environment may improve (with enriched environments or worsen (with negative and maternal separation stress the cognitive ability of pups that were prenatally exposed to ethanol as well as their matched controls. In this review, we will discuss operational epigenetic mechanisms involved in the

Synthesis, characterization and anti-fungal evaluation of Ni(II and Cu(II complexes with a derivative of 4-aminoantipyrine

Directory of Open Access Journals (Sweden)

Monika Tyagi

2017-01-01

Full Text Available Transition metal complexes of Ni(II and Cu(II metal ions with the general stoichiometry [M(LX]X and [M(LSO4], where M = Ni(II and Cu(II, L = (1E-N-((5-((E-(2,3-dimethyl-1-phenyl-4-pyrazolineiminomethylthiophen-2-ylmethylene-2,3-dimethyl-1-phenyl-4-pyrazolineamine and X = Cl−, NO3− and SO42−, have been synthesized and characterized. The synthesized ligand and metal complexes were characterized by 1H NMR, IR, mass spectrometry, UV–Vis spectra and EPR. In molecular modelling, the geometries of the Schiff's base and metal complexes were fully optimized with respect to the energy using the 6-31g(d,p basis set. The nickel(II complexes were found to have octahedral geometry, whereas the copper(II complexes were of tetragonal geometry. The covalency factor (β and orbital reduction factor (k suggest the covalent nature of the complexes. To develop broad spectrum new molecules against seed-borne fungi, the minimum inhibitory concentration (MIC of the ligand and its metal complexes was evaluated by the serial dilution method.

Luminescent Oxygen Gas Sensors Based on Nanometer-Thick Hybrid Films of Iridium Complexes and Clay Minerals

Directory of Open Access Journals (Sweden)

Hisako Sato

2014-01-01

Full Text Available The use of Ir(III complexes in photo-responsive molecular devices for oxygen gas sensing is reviewed. Attention is focused on the immobilization of Ir(III complexes in organic or inorganic host materials such as polymers, silica and clays in order to enhance robustness and reliability. Our recent works on constructing nanometer-thick films comprised of cyclometalated cationic Ir(III complexes and clay minerals are described. The achievement of multi-emitting properties in response to oxygen pressure is demonstrated.

Priorities for autism spectrum disorder risk communication and ethics.

Science.gov (United States)

Yudell, Michael; Tabor, Holly K; Dawson, Geraldine; Rossi, John; Newschaffer, Craig

2013-11-01

Autism spectrum disorders are an issue of increasing public health significance. The incidence of autism spectrum disorders has been increasing in recent years, and they are associated with significant personal and financial impacts for affected persons and their families. In recent years, a large number of scientific studies have been undertaken, which investigate genetic and environmental risk factors for autism, with more studies underway. At present, much remains unknown regarding autism spectrum disorder risk factors, but the emerging picture of causation is in many cases complex, with multiple genes and gene-environment interactions being at play. The complexity and uncertainty surrounding autism spectrum disorder risk factors raise a number of questions regarding the ethical considerations that should be taken into account when undertaking autism spectrum disorder risk communication. At present, however, little has been written regarding autism spectrum disorder risk communication and ethics. This article summarizes the findings of a recent conference investigating ethical considerations and policy recommendations in autism spectrum disorder risk communication, which to the authors' knowledge is the first of its kind. Here, the authors discuss a number of issues, including uncertainty; comprehension; inadvertent harm; justice; and the appropriate roles of clinicians, scientists, and the media in autism spectrum disorder risk communication.

Effect of Water on HEMA Conversion by FT-IR Spectroscopy

Directory of Open Access Journals (Sweden)

TS. Jafarzadeh Kashi

2007-09-01

Full Text Available Objective: The use of HEMA as a biocompatible material in dentin bonding systems and its potential for clinical applications has been well established. Excess water can affect conversion of bonding resins. The aim of this study was to survey the effect of water on the degree of conversion of HEMA by Fourier Transform Infra-red Spectroscopy (FT-IR.Materials and Methods: In this experimental study, distilled water was added in amounts of 0, 0.05, 0.1, 0.2, and 0.4 ml to 1 ml of curable HEMA solution. Six repetitions per wa-ter ratio were made and investigated. Each sample was polymerized for 60 seconds. De-gree of conversion was obtained from the absorbance IR-Spectrum of the materials before and after polymerization by FT-IR spectroscopy. One way ANOVA and Tukey-HSD were carried out to compare and detect any differences among groups.Results: Statistical analysis indicates highly significant difference between pairs of groups at level (P<0.001. The results showed a trend of decreasing in HEMA conversion with increasing water. Degree of conversion changes significantly within the 0.05 ml to 0.2 ml water range. However, degree of conversion did not change after reaching 0.02 ml and before 0.05.Conclusion: Degree of conversion of HEMA decreased by increasing water. The most dramatic effect of water on the polymerization process occurs within a range which exists under clinical conditions. The reason that the degree of conversion did not show signifi-cant result before 0.05 ml may be related to the hydrophilic nature of HEMA.

Density functional study of the L10-αIrV transition in IrV and RhV

International Nuclear Information System (INIS)

Mehl, Michael J.; Hart, Gus L.W.; Curtarolo, Stefano

2011-01-01

Research highlights: → The computational determination of the ground state of a material can be a difficult task, particularly if the ground state is uncommon and so not found in usual databases. In this paper we consider the alpha-IrV structure, a low temperature structure found only in two compounds, IrV and RhV. In both cases this structure can be considered as a distorted tetragonal structure, and the tetragonal 'L1 0 ' structure is the high temperature structure for both compounds. We show, however, that the logical path for the transition from the L1 0 to the alpha-IrV structure is energetically forbidden, and find a series of unstable and metastable structures which have a lower energy than the L1 0 phase, but are higher in energy than the alpha-IrV phase. We also consider the possibility of the alpha-IrV structure appearing in neighboring compounds. We find that both IrTi and RhTi are candidates. - Abstract: Both IrV and RhV crystallize in the αIrV structure, with a transition to the higher symmetry L1 0 structure at high temperature, or with the addition of excess Ir or Rh. Here we present evidence that this transition is driven by the lowering of the electronic density of states at the Fermi level of the αIrV structure. The transition has long been thought to be second order, with a simple doubling of the L1 0 unit cell due to an unstable phonon at the R point (0 1/2 1/2). We use first-principles calculations to show that all phonons at the R point are, in fact, stable, but do find a region of reciprocal space where the L1 0 structure has unstable (imaginary frequency) phonons. We use the frozen phonon method to examine two of these modes, relaxing the structures associated with the unstable phonon modes to obtain new structures which are lower in energy than L1 0 but still above αIrV. We examine the phonon spectra of these structures as well, looking for instabilities, and find further instabilities, and more relaxed structures, all of which have

Joint switched multi-spectrum and transmit antenna diversity for spectrum sharing systems

KAUST Repository

Sayed, Mostafa M.

2013-10-01

In spectrum sharing systems, a secondary user (SU) is allowed to share the spectrum with a primary (licensed) network under the condition that the interference observed at the receivers of the primary users (PU-Rxs) is below a predetermined level. In this paper, we consider a secondary network comprised of a secondary transmitter (SU-Tx) equipped with multiple antennas and a single-antenna secondary receiver (SU-Rx) sharing the same spectrum with multiple primary users (PUs), each with a distinct spectrum. We develop transmit antenna diversity schemes at the SU-Tx that exploit the multi-spectrum diversity provided by the existence of multiple PUs so as to optimize the signal-to-noise ratio (SNR) at the SU-Rx. In particular, assuming bounded transmit power at the SU-Tx, we develop switched selection schemes that select the primary spectrum and the SU-Tx transmit antenna that maintain the SNR at the SU-Rx above a specific threshold. Assuming Rayleigh fading channels and binary phase-shift keying (BPSK) transmission, we derive the average bit-error-rate (BER) and average feedback load expressions for the proposed schemes. For the sake of comparison, we also derive a BER expression for the optimal selection scheme that selects the best antenna/spectrum pair that maximizes the SNR at the SU-Rx, in exchange of high feedback load and switching complexity. Finally, we show that our analytical results are in perfect agreement with the simulation results. © 2013 IEEE.

PENDIDIKAN AKHLAK MUSLIMAT MELALUISYA’IR : ANALISIS GENDER ATAS AJARAN SYI’IR MUSLIMAT KARYA NYAI WANIFAH KUDUS

Directory of Open Access Journals (Sweden)

Nur Said

2016-03-01

Full Text Available Penelitian ini difokuskan pada tiga hal: (1 Apakah karakteristik lingkup isi Syi’ir Muslimat?, (2 Bagai-manakah kondisi sosial budaya pada saat naskah ditulis oleh penulis?, (3 Apa nilai-nilai pendidikan moral bagi perempuan Muslim di isi Syi’ir Muslimat dalam perspektif gender?. Penelitian ini menggunakan pendekatan filologi dengan meningkatkan penggunaan analisis gender. Hasil dari penelitian ini adalah: Pertama, Syi’ir Muslimat ditulis oleh Nyai Wanifah, seorang wanita yang hidup pada zaman kolonial Belanda dipesantren tradisi di Kudus, Jawa Tengah. Kedua, beberapa nilai pendidikan moral di Syi’ir Muslimatantara lain: (1 Pentingnya pendidikan moral, (2 Bahaya perempuan bodoh; (3 Pentingnya belajar bagi perempuan di usia dini, (4 Etika menghias diri; (5 Bahaya materialisme, (6 Etika hubungan keluarga; (7 Dari rumah untuk mencapai surga; (8 Berhati-hatilah dengan tipu iblis; (9 Hindari perzinahan; (10 yang penting dari penutupan aurot; (11 yang ditujukan kepada orang tua. Ketiga, meskipun ada beberapa senyawa yang bias gender dalam Syi’ir Muslimat misalnya: (a Ada penjelasan yang menunjukkan bahwa perempuan lebih rendah dibandingkan laki-laki dalam derajat, (2 Pernyataan bahwa wanita bicara dibandingkan laki-laki, (3 wanita hanya cocok di wilayah domestik; Namun secara umum nasihat di syi’ir masih sangat relafen dalam konteks sekarang, terutama untuk memberikan solusi alternatif dalam merespon krisis moral bangsa terutama pada wanita generasi muda. Kata kunci: Syi’ir Muslimat, Pendidikan Karakter, Analisis Gender. This study focused on three things: (1 What is the characteristics of the scope of contents of Syi’ir Muslimat?, (2 What is the socio-cultural conditions at the time the manuscript was written by the author?, (3 What are the moral education values for Muslim women in the content of Syi’ir Muslimat in the perspective of gender?. This research uses a philological approach with enhanced use of gender analysis. The

FT-IR spectroscopic studies of protein secondary structures for breast cancer diagnosis

International Nuclear Information System (INIS)

Karamancheva, I; Simonova, D.; Milev, A.

2013-01-01

Full text: Roughly 14 million new cancer cases and 8 million cancer deaths have occurred worldwide in 2012. At least 30 % of all cancer cases and 40 % of the cancer deaths should be avoided by improving the early detection. Fourier transform infrared (FT-IR) spectroscopy has shown many advantages as a tool for the detection of cancer over the traditional methods such as histopathological analysis, X-ray transmission, ultrasonic and computer tomography techniques. With the aim to establish the FT-IR spectroscopy as an alternative method for the diagnosis of human cancers, we have made several studies to examine in details the spectroscopic properties of normal and carcinomatous tissues. Human breast tissues were obtained immediately after surgical breast resection with the informed patient's consent. In our studies we made extensive use of Fourier self-deconvolution, second-order derivatization, difference spectra, curve-fitting procedures and quantitative determinations according to Beer's law. Cancer is a multi-step process. Characteristic differences in both the frequencies and the intensity ratios of several bands have been revealed. Considerable differences have been found in the spectral patterns. The most important and informative region in the mid-IR for determination of protein secondary structure is the amide I and amide II region. The bands between 1730 and 1600 cm -1 are highly sensitive to conformational changes. Considerable changes were observed in the A1735/A1652 absorbance ratio, which provides a measure for the content of a- helix and P-sheet domains. Our investigations have shown that the major biomarker peaks are in the amide I and amide II regions. In the so called 'fingerprint region' many molecular constituents such as lipids, phospholipids, proteins, DNA and RNA, carbohydrates and metabolites may overlap and the quantitative interpretation is impossible. The spectrum may therefore reflect only the average biochemical composition.; key words

Intramolecular hydrogen bonding in N-salicylideneaniline: FT-IR spectrum and quantum chemical calculations

Science.gov (United States)

Moosavi-Tekyeh, Zainab; Dastani, Najmeh

2015-12-01

FT-IR and FT-Raman spectra of N-salicylideneaniline (SAn) and its deuterated analogue (D-SAn) are recorded, and the theoretical calculations are performed on their molecular structures and vibrational frequencies. The same calculations are performed for SAn in different solutions using the polarizable conductor continuum model (CPCM) method. Comparisons between the spectra obtained and the corresponding theoretical calculations are used to assign the vibrational frequencies for these compounds. The spectral behavior of SAn upon deuteration is also used to distinguish the positions of OH vibrational frequencies. The hydrogen bond strength of SAn is investigated by applying the atoms-in-molecules (AIM) theory, natural bond orbital (NBO) analysis, and geometry calculations. The harmonic vibrational frequencies of SAn are calculated at B3LYP and X3LYP levels of theory using 6-31G*, 6-311G**, and 6-311++G** basis sets. The AIM results support a medium hydrogen bonding in SAn. The observed νOH/νOD and γOH/γOD for SAn appear at 2940/2122 and 830/589 cm-1, respectively.

Attenuated total reflectance-FT-IR spectroscopy for gunshot residue analysis: potential for ammunition determination.

Science.gov (United States)

Bueno, Justin; Sikirzhytski, Vitali; Lednev, Igor K

2013-08-06

The ability to link a suspect to a particular shooting incident is a principal task for many forensic investigators. Here, we attempt to achieve this goal by analysis of gunshot residue (GSR) through the use of attenuated total reflectance (ATR) Fourier transform infrared spectroscopy (FT-IR) combined with statistical analysis. The firearm discharge process is analogous to a complex chemical process. Therefore, the products of this process (GSR) will vary based upon numerous factors, including the specific combination of the firearm and ammunition which was discharged. Differentiation of FT-IR data, collected from GSR particles originating from three different firearm-ammunition combinations (0.38 in., 0.40 in., and 9 mm calibers), was achieved using projection to latent structures discriminant analysis (PLS-DA). The technique was cross (leave-one-out), both internally and externally, validated. External validation was achieved via assignment (caliber identification) of unknown FT-IR spectra from unknown GSR particles. The results demonstrate great potential for ATR-FT-IR spectroscopic analysis of GSR for forensic purposes.

The IRS-1 signaling system.

Science.gov (United States)

Myers, M G; Sun, X J; White, M F

1994-07-01

Insulin-receptor substrate 1 (IRS-1) is a principal substrate of the receptor tyrosine kinase for insulin and insulin-like growth factor 1, and a substrate for a tyrosine kinase activated by interleukin 4. IRS-1 undergoes multisite tyrosine phosphorylation and mediates downstream signals by 'docking' various proteins that contain Src homology 2 domains. IRS-1 appears to be a unique molecule; however, 4PS, a protein found mainly in hemopoietic cells, may represent another member of this family.

Synthesis, spectral, thermal studies and electrical conductivity of Co (II) and Ni (II) complexes 3-[4-dimethylaminophenyl]-1-(2-pyridyl) prop-2-en-1-one (DMAPP)

Energy Technology Data Exchange (ETDEWEB)

Gaber, Mohamed, E-mail: abuelazm@yahoo.com [Chemistry Department, Faculty of Science, Tanta University, 31527 Tanta (Egypt); Al-Daly, Samy; Fayed, Tarek [Chemistry Department, Faculty of Science, Tanta University, 31527 Tanta (Egypt); El-Sayed, Yousif [Department of Chemistry, Faculty of Science, Tanta University, Tanta (Egypt)

2015-01-15

Co(II) and Ni(II) complexes of 3-[4-dimethylaminophenyl]-1-(2-pyridyl)prop-2-en-1-one have been prepared and characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility measurements, IR, electronic spectra as well as thermal studies. The magnetic and spectral studies suggested the octahedral geometry for Co(II) and Ni(II) complexes. The kinetic parameters of the thermal decomposition stages have been evaluated using Coats–Redfern method. The electrical conductivity of the titled ligand and its Co(II) complexes was studied. The effects of different alcoholic solvents, pH and temperature on the complexation formation were considered. Also, the effect of Co(II) and Ni(II) ions on the emission spectrum of the free DMAPP was assigned. The stoichiometry of the metal complexes, the conditional formation constant, free energy, Beer{sup '}s law, molar extinction coefficient as well as specific absorptivity were evaluated. The ability of using the titled ligand as metalochromic indicator in complexometric titration was studied.

pH Mapping on Tooth Surfaces for Quantitative Caries Diagnosis Using Micro Ir/IrOx pH Sensor.

Science.gov (United States)

Ratanaporncharoen, Chindanai; Tabata, Miyuki; Kitasako, Yuichi; Ikeda, Masaomi; Goda, Tatsuro; Matsumoto, Akira; Tagami, Junji; Miyahara, Yuji

2018-04-03

A quantitative diagnostic method for dental caries would improve oral health, which directly affects the quality of life. Here we describe the preparation and application of Ir/IrOx pH sensors, which are used to measure the surface pH of dental caries. The pH level is used as an indicator to distinguish between active and arrested caries. After a dentist visually inspected and defined 18 extracted dentinal caries at various positions as active or arrested caries, the surface pH values of sound and caries areas were directly measured with an Ir/IrOx pH sensor with a diameter of 300 μm as a dental explorer. The average pH values of the sound root, the arrested caries, and active caries were 6.85, 6.07, and 5.30, respectively. The pH obtained with an Ir/IrOx sensor was highly correlated with the inspection results by the dentist, indicating that the types of caries were successfully categorized. This caries testing technique using a micro Ir/IrOx pH sensor provides an accurate quantitative caries evaluation and has potential in clinical diagnosis.

Polarised IR-microscope spectra of guanidinium hydrogensulphate single crystal.

Science.gov (United States)

Drozd, M; Baran, J

2006-07-01

Polarised IR-microscope spectra of C(NH(2))(3)*HSO(4) small single crystal samples were measured at room temperature. The spectra are discussed on the basis of oriented gas model approximation and group theory. The stretching nuOH vibration of the hydrogen bond with the Ocdots, three dots, centeredO distance of 2.603A gives characteristic broad AB-type absorption in the IR spectra. The changes of intensity of the AB bands in function of polariser angle are described. Detailed assignments for bands derived from stretching and bending modes of sulphate anions and guanidinium cations were performed. The observed intensities of these bands in polarised infrared spectra were correlated with theoretical calculation of directional cosines of selected transition dipole moments for investigated crystal. The vibrational studies seem to be helpful in understanding of physical and chemical properties of described compound and also in design of new complexes with exactly defined behaviors.

Polarized IR-microscope spectra of guanidinium hydrogenselenate single crystal.

Science.gov (United States)

Drozd, M; Baran, J

2005-10-01

The polarized IR-microscope spectra of C(NH2)3.HSeO4 small single crystal samples were measured at room temperature. The spectra are discussed with the framework of oriented gas model approximation and group theory. The stretching nuOH vibration of the hydrogen bond with the O...O distance of 2.616 A gives characteristic broad AB-type absorption in the IR spectra. The changes of intensity of the AB bands in function of polarizer angle are described. Detailed assignment for bands derived from stretching and bending modes of selenate anions and guanidinium cations were performed. The observed intensities of these bands in polarized infrared spectra were correlated with theoretical calculation of directional cosines of selected transition dipole moments for investigated crystal. The vibrational studies seem to be helpful in understanding of physical and chemical properties of described compound and also in design of new complexes with exactly defined behaviors.

Multiplexing of spatial modes in the mid-IR region

Science.gov (United States)

Gailele, Lucas; Maweza, Loyiso; Dudley, Angela; Ndagano, Bienvenu; Rosales-Guzman, Carmelo; Forbes, Andrew

2017-02-01

Traditional optical communication systems optimize multiplexing in polarization and wavelength both trans- mitted in fiber and free-space to attain high bandwidth data communication. Yet despite these technologies, we are expected to reach a bandwidth ceiling in the near future. Communications using orbital angular momentum (OAM) carrying modes offers infinite dimensional states, providing means to increase link capacity by multiplexing spatially overlapping modes in both the azimuthal and radial degrees of freedom. OAM modes are multiplexed and de-multiplexed by the use of spatial light modulators (SLM). Implementation of complex amplitude modulation is employed on laser beams phase and amplitude to generate Laguerre-Gaussian (LG) modes. Modal decomposition is employed to detect these modes due to their orthogonality as they propagate in space. We demonstrate data transfer by sending images as a proof-of concept in a lab-based scheme. We demonstrate the creation and detection of OAM modes in the mid-IR region as a precursor to a mid-IR free-space communication link.

Comparison of Fiber Optic and Conduit Attenuated Total Reflection (ATR) Fourier Transform Infrared (FT-IR) Setup for In-Line Fermentation Monitoring.

Science.gov (United States)

Koch, Cosima; Posch, Andreas E; Herwig, Christoph; Lendl, Bernhard

2016-12-01

The performance of a fiber optic and an optical conduit in-line attenuated total reflection mid-infrared (IR) probe during in situ monitoring of Penicillium chrysogenum fermentation were compared. The fiber optic probe was connected to a sealed, portable, Fourier transform infrared (FT-IR) process spectrometer via a plug-and-play interface. The optical conduit, on the other hand, was connected to a FT-IR process spectrometer via a knuckled probe with mirrors that had to be adjusted prior to each fermentation, which were purged with dry air. Penicillin V (PenV) and its precursor phenoxyacetic acid (POX) concentrations were determined by online high-performance liquid chromatography and the obtained concentrations were used as reference to build partial least squares regression models. Cross-validated root-mean-square errors of prediction were found to be 0.2 g L -1 (POX) and 0.19 g L -1 (PenV) for the fiber optic setup and 0.17 g L -1 (both POX and PenV) for the conduit setup. Higher noise-levels and spectrum-to-spectrum variations of the fiber optic setup lead to higher noise of estimated (i.e., unknown) POX and PenV concentrations than was found for the conduit setup. It seems that trade-off has to be made between ease of handling (fiber optic setup) and measurement accuracy (optical conduit setup) when choosing one of these systems for bioprocess monitoring. © The Author(s) 2016.

Synthesis, characterization and biological activity of symmetric dinuclear complexes derived from a novel macrocyclic compartmental ligand

Energy Technology Data Exchange (ETDEWEB)

Mruthyunjayaswamy, B.H.M.; Ijare, Omkar B.; Jadegoud, Y. [Gulbarga University (India). Dept. of Chemistry]. E-mail: bhmmswamy53@rediffmail.com

2005-07-15

A phenol based novel macrocyclic binucleating compartmental ligand N,N-bis(2,6-diiminomethyl-4-methyl-1-hydroxyphenyl)malonoyldicarboxamide was prepared. The complexes were prepared by template method by reacting 2,6-diformyl-4-methylphenol, malonoyl dihydrazide and the metal chlorides of Cu(II), Ni(II), Co(II), Cd(II), Zn(II) and Hg(II) in methanol to get a series of dinuclear complexes. The complexes were characterized by elemental analyses, conductivity measurements, magnetic susceptibility data, IR, UV-Vis, ESR, NMR and FAB mass spectral data. The dinuclear nature of the complexes was confirmed on the basis of elemental analyses, magnetic susceptibility, ESR and FAB mass spectral data. The ligand as well as Cu(II), Ni(II), Co(II) and Zn(II) complexes were tested for their antibacterial and antifungal properties against Escherichia coli, Staphyloccocus aureus, Aspergillus niger and Fusarium oxysporum. Magnetic susceptibility measurements of Cu(II), Ni(II) and Co(II) complexes reveal that these complexes exhibit antiferromagnetic coupling behavior due to the presence of two metal ions in close proximity. FAB mass spectrum of the Cu(II) complex gave a clear evidence for the dinuclear nature. The ligand and the complexes were found to be less active against the tested bacteria, but the ligand alone was found active against the fungus Fusarium oxysporum. (author)

Synthesis, characterization and biological activity of symmetric dinuclear complexes derived from a novel macrocyclic compartmental ligand

International Nuclear Information System (INIS)

Mruthyunjayaswamy, B.H.M.; Ijare, Omkar B.; Jadegoud, Y.

2005-01-01

A phenol based novel macrocyclic binucleating compartmental ligand N,N-bis(2,6-diiminomethyl-4-methyl-1-hydroxyphenyl)malonoyldicarboxamide was prepared. The complexes were prepared by template method by reacting 2,6-diformyl-4-methylphenol, malonoyl dihydrazide and the metal chlorides of Cu(II), Ni(II), Co(II), Cd(II), Zn(II) and Hg(II) in methanol to get a series of dinuclear complexes. The complexes were characterized by elemental analyses, conductivity measurements, magnetic susceptibility data, IR, UV-Vis, ESR, NMR and FAB mass spectral data. The dinuclear nature of the complexes was confirmed on the basis of elemental analyses, magnetic susceptibility, ESR and FAB mass spectral data. The ligand as well as Cu(II), Ni(II), Co(II) and Zn(II) complexes were tested for their antibacterial and antifungal properties against Escherichia coli, Staphyloccocus aureus, Aspergillus niger and Fusarium oxysporum. Magnetic susceptibility measurements of Cu(II), Ni(II) and Co(II) complexes reveal that these complexes exhibit antiferromagnetic coupling behavior due to the presence of two metal ions in close proximity. FAB mass spectrum of the Cu(II) complex gave a clear evidence for the dinuclear nature. The ligand and the complexes were found to be less active against the tested bacteria, but the ligand alone was found active against the fungus Fusarium oxysporum. (author)

Molecular structure, vibrational analysis (IR and Raman) and quantum chemical investigations of 1-aminoisoquinoline

Science.gov (United States)

Sivaprakash, S.; Prakash, S.; Mohan, S.; Jose, Sujin P.

2017-12-01

Quantum chemical calculations of energy and geometrical parameters of 1-aminoisoquinoline [1-AIQ] were carried out by using DFT/B3LYP method using 6-311G (d,p), 6-311G++(d,p) and cc-pVTZ basis sets. The vibrational wavenumbers were computed for the energetically most stable, optimized geometry. The vibrational assignments were performed on the basis of potential energy distribution (PED) using VEDA program. The NBO analysis was done to investigate the intra molecular charge transfer of the molecule. The frontier molecular orbital (FMO) analysis was carried out and the chemical reactivity descriptors of the molecule were studied. The Mulliken charge analysis, molecular electrostatic potential (MEP), HOMO-LUMO energy gap and the related properties were also investigated at B3LYP level. The absorption spectrum of the molecule was studied from UV-Visible analysis by using time-dependent density functional theory (TD-DFT). Fourier Transform Infrared spectrum (FT-IR) and Raman spectrum of 1-AIQ compound were analyzed and recorded in the range 4000-400 cm-1 and 3500-100 cm-1 respectively. The experimentally determined wavenumbers were compared with those calculated theoretically and they complement each other.

Spectroscopic and thermogravimetric study of nickel sulfaquinoxaline complex

International Nuclear Information System (INIS)

Tailor, Sanjay M.; Patel, Urmila H.

2016-01-01

The ability of sulfaquinoxaline (4-Amino-N-2-quinoxalinylbenzenesulfonamide) to form metal complexes are investigated. The nickel complex of sulfaquinoxaline is prepared by reflux method and characterized by CHN analysis and IR spectra. The results of IR spectral data suggest that the binding of nickel atom to the sulfonamidic nitrogen are in good agreement. The thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential thermogravimetric (DTG) analysis of nickel sulfaquinoxaline are carried out from ambient temperature to 750°C in inert nitrogen atmosphere. The activation energy, enthalpy, entropy and Gibbs free energy of nickel sulfaquinoxaline complex is determined from the thermal curves using Broido method. The results are reported in this paper.

Preparation and photoluminescence enhancement in terbium(III ternary complexes with β-diketone and monodentate auxiliary ligands

Directory of Open Access Journals (Sweden)

Devender Singh

2016-12-01

Full Text Available A series of new solid ternary complexes of terbium(III ion based on β-diketone ligand acetylacetone (acac and monodentate auxiliary ligands (aqua/urea/triphenylphosphineoxide/pyridine-N-oxide had been prepared. The structural characterizations of synthesized ternary compounds were studied by means of elemental analysis, infrared (IR, and proton nuclear magnetic resonance (NMR spectral techniques. The optical characteristics were investigated with absorption as well as photoluminescence spectroscopy. Thermal behavior of compounds was examined by TGA/DTA analysis and all metal complexes were found to have good thermal stability. The luminescence decay time of complexes were also calculated by monitoring at emission wavelength corresponding to 5D4 → 7F5 transition. A comparative inspection of the luminescent behavior of prepared ternary compounds was performed in order to determine the function of auxiliary ligands in the enhancement of luminescence intensity produced by central terbium(III ion. The color coordinates values suggested that compounds showed bright green emission in visible region in electromagnetic spectrum. Complexes producing green light could play a significant role in the fabrication of efficient light conversion molecular devices for display purposes and lightning systems.

Successful synthesis and thermal stability of immiscible metal Au-Rh, Au-Ir andAu-Ir-Rh nanoalloys

Science.gov (United States)

Shubin, Yury; Plyusnin, Pavel; Sharafutdinov, Marat; Makotchenko, Evgenia; Korenev, Sergey

2017-05-01

We successfully prepared face-centred cubic nanoalloys in systems of Au-Ir, Au-Rh and Au-Ir-Rh, with large bulk miscibility gaps, in one-run reactions under thermal decomposition of specially synthesised single-source precursors, namely, [AuEn2][Ir(NO2)6], [AuEn2][Ir(NO2)6] х [Rh(NO2)6]1-х and [AuEn2][Rh(NO2)6]. The precursors employed contain all desired metals ‘mixed’ at the atomic level, thus providing significant advantages for obtaining alloys. The observations using high-resolution transmission electron microscopy show that the nanoalloy structures are composed of well-dispersed aggregates of crystalline domains with a mean size of 5 ± 3 nm. Еnergy dispersive x-ray spectroscopy and x-ray powder diffraction (XRD) measurements confirm the formation of AuIr, AuRh, AuIr0.75Rh0.25, AuIr0.50Rh0.50 and AuIr0.25Rh0.75 metastable solid solutions. In situ high-temperature synchrotron XRD (HTXRD) was used to study the formation mechanism of nanoalloys. The observed transformations are described by the ‘conversion chemistry’ mechanism characterised by the primary development of particles comprising atoms of only one type, followed by a chemical reaction resulting in the final formation of a nanoalloy. The obtained metastable nanoalloys exhibit essential thermal stability. Exposure to 180 °C for 30 h does not cause any dealloying process.

DFT study of structure, IR and Raman spectra of the fluorescent "Janus" dendron built from cyclotriphosphazene core

Science.gov (United States)

Furer, V. L.; Vandyukova, I. I.; Vandyukov, A. E.; Fuchs, S.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

2011-11-01

The FTIR and FT-Raman spectra of the zero generation dendron, possessing five fluorescent dansyl terminal groups, cyclotriphosphazene core, and one carbamate function G0v were studied. The structural optimization and normal mode analysis were performed for G0v dendron on the basis of the density functional theory (DFT). The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that dendron molecule G0v has a concave lens structure with slightly non-planar cyclotriphosphazene core. The experimental IR and Raman spectra of G0v dendron were interpreted by means of potential energy distributions. Relying on DFT calculations a complete vibrational assignment is proposed. The frequency of ν(N-H) band in the IR spectrum reveal the presence of H-bonds in the G0v dendron.

Oxovanadium(IV) complexes of non-steroidal anti-inflammatory drugs: synthesis, spectroscopy, and antimicrobial activity

International Nuclear Information System (INIS)

Muhammad, N.; Ali, S.; Shahzadi, S.; Khan, A.N.

2008-01-01

Oxovanadium(IV) complexes with four different non-steroidal anti-inflammatory drugs have been synthesized. These complexes were characterized by different analytical techniques such as CHN, IR, UV-Vis spectroscopy, and mass spectrometry. The IR data show the bidentate nature of the ligands and reveal hexacoordinate geometry in the solid state. The complexes were tested for their biological activity against six different bacterial strains and plant pathogens, and all complexes showed good biological activity with few exceptions [ru

Characteristics of Ir/Au transition edge sensor

International Nuclear Information System (INIS)

Kunieda, Yuichi; Ohno, Masashi; Nakazawa, Masaharu; Takahashi, Hiroyuki; Fukuda, Daiji; Ohkubo, Masataka

2004-01-01

A new type of microcalorimeter has been developed using a transition edge sensor (TES) and an electro-thermal feedback (ETF) method to achieve higher energy resolution and higher count rate. We are developing a superconducting Ir-based transition edge sensor (TES) microcalorimeters. To improve thermal conductivity and achieve higher energy resolution with an Ir-TES, we fabricated an Ir/Au bilayer TES by depositing gold on Ir and investigated the influence of intermediate between superconducting and normal states at the transition edge for signal responses by microscopic observation in the Ir/Au-TES. (T. Tanaka)

ESR investigation of NR and IR rubber vulcanized with different cross-link agents

Directory of Open Access Journals (Sweden)

P. Posadas

2016-01-01

Full Text Available This study evaluates the formation of radical species in natural rubber (NR and poly-isoprene rubber (IR during the vulcanization process and the uniaxial deformation of the formed networks by means of Electron Spin Resonance (ESR. Vulcanization of NR and IR always shows a radical pathway, where the different vulcanization systems dictate the concentration of radical species in the course of this complex process. The greatest concentration of radicals were detected during the vulcanization with sulfur/accelerator based on efficient systems (EV, followed by conventional (CV and sulfur donor systems, whereas azide and organic peroxide agents showed smaller concentration of radicals. Independently of the vulcanization system, certain amount of radicals was detected on the vulcanized samples after the end of the vulcanization process. Comparison between different matrices demonstrates that NR always shows higher concentration of radicals than IR in the vulcanization process as well as during uniaxial deformation, fact that could be associated to the presence of nonrubber components in NR.

Changes in EEG complexity with electroconvulsive therapy in a patient with autism spectrum disorders: a multiscale entropy approach

Directory of Open Access Journals (Sweden)

Ryoko eOkazaki

2015-02-01

Full Text Available Autism spectrum disorders (ASD are heterogeneous neurodevelopmental disorders that are reportedly characterized by aberrant neural networks. Recently developed multiscale entropy analysis (MSE can characterize the complexity inherent in EEG dynamics over multiple temporal scales in the dynamics of neural networks. We encountered an 18-year-old man with ASD whose refractory catatonic obsessive–compulsive symptoms were improved dramatically after electroconvulsive therapy (ECT. In this clinical case study, we strove to clarify the neurophysiological mechanism of ECT in ASD by assessing EEG complexity using MSE. Along with ECT, the frontocentral region showed decreased EEG complexity at higher temporal scales, whereas the occipital region expressed an increase at lower temporal scales. Furthermore, these changes were associated with clinical improvement associated with the elevation of brain-derived neurotrophic factor, which is a molecular hypothesis of ECT, playing key roles in ASD pathogenesis. Changes in EEG complexity in a region-specific and temporal scale-specific manner we found might reflect atypical EEG dynamics in ASD. Although MSE is not a direct approach to measuring neural connectivity and the results are from only a single case, they might reflect specific aberrant neural network activity and the therapeutic neurophysiological mechanism of ECT in ASD.

Jaunesnių ir vyresnių klasių mokinių konfliktų ir jų sprendimų ypatumai

OpenAIRE

Stočkutė, Jovita

2012-01-01

Tyrimo objektas – jaunesnių ir vyresnių klasių mokinių konfliktai ir jų sprendimų ypatumai. Tyrimo tikslas – išanalizuoti jaunesnių ir vyresnių klasių mokinių konfliktus ir jų sprendimų ypatumus. Hipotezės – keliame prielaidas, kad - vyresnių klasių mokiniai konfliktuoti pamokose linkę labiau, nei jaunesnių klasių mokiniai. - vyresnių klasių mokiniai naudoja įvairesnes konflikto sprendimo strategijas nei jaunesnių klasių mokiniai. Tyrimo uždaviniai: 1. Atskleisti jaune...

Imaging with electromagnetic spectrum applications in food and agriculture

CERN Document Server

Jayasuriya, Hemantha

2014-01-01

This book demonstrates how imaging techniques, applying different frequency bands from the electromagnetic spectrum, are used in scientific research. Illustrated with numerous examples this book is structured according to the different radiation bands: From Gamma-rays over UV and IR to radio frequencies. In order to ensure a clear understanding of the processing methodologies, the text is enriched with descriptions of how digital images are formed, acquired, processed and how to extract information from them. A special emphasis is given to the application of imaging techniques in food and agriculture research.

Efficacy of a radiation safety education initiative in reducing radiation exposure in the pediatric IR suite

International Nuclear Information System (INIS)

Sheyn, David D.; Racadio, John M.; Patel, Manish N.; Racadio, Judy M.; Johnson, Neil D.; Ying, Jun

2008-01-01

The use of ionizing radiation is essential for diagnostic and therapeutic imaging in the interventional radiology (IR) suite. As the complexity of procedures increases, radiation exposure risk increases. We believed that reinforcing staff education and awareness would help optimize radiation safety. To evaluate the effect of a radiation safety education initiative on IR staff radiation safety practices and patient radiation exposure. After each fluoroscopic procedure performed in the IR suite during a 4-month period, dose-area product (DAP), fluoroscopy time, and use of shielding equipment (leaded eyeglasses and hanging lead shield) by IR physicians were recorded. A lecture and article were then given to IR physicians and technologists that reviewed ALARA principles for optimizing radiation dose. During the following 4 months, those same parameters were recorded after each procedure. Before education 432 procedures were performed and after education 616 procedures were performed. Physician use of leaded eyeglasses and hanging shield increased significantly after education. DAP and fluoroscopy time decreased significantly for uncomplicated peripherally inserted central catheters (PICC) procedures and non-PICC procedures after education, but did not change for complicated PICC procedures. Staff radiation safety education can improve IR radiation safety practices and thus decrease exposure to radiation of both staff and patients. (orig.)

Teaching IR to Medical Students: A Call to Action.

Science.gov (United States)

Lee, Aoife M; Lee, Michael J

2018-02-01

Interventional radiology (IR) has grown rapidly over the last 20 years and is now an essential component of modern medicine. Despite IR's increasing penetration and reputation in healthcare systems, IR is poorly taught, if taught at all, in most medical schools. Medical students are the referrers of tomorrow and potential IR recruits and deserve to be taught IR by expert IRs. The lack of formal IR teaching curricula in many medical schools needs to be addressed urgently for the continued development and dissemination of, particularly acute, IR services throughout Europe. We call on IRs to take up the baton to teach IR to the next generation of doctors.

Diphosphine- and CO-Induced Fragmentation of Chloride-bridged Dinuclear Complex and Cp*Ir(mu-Cl)(3)Re(CO)(3) and Attempted Synthesis of Cp*Ir(mu-Cl)(3)Mn(CO)(3): Spectroscopic Data and X-ray Diffraction Structures of the Pentamethylcyclopentadienyl Compounds [Cp*IrCl{(Z)-Ph2PCH = CHPPh2}][Cl]center dot 2CHCl(3) and Cp*Ir(CO)Cl-2

Energy Technology Data Exchange (ETDEWEB)

Hammons, Casey [University of North Texas; Wang, Xiaoping [ORNL; Nesterov, Vladimir [University of North Texas; Richmond, Michael G. [University of North Texas

2010-01-01

The confacial bioctahedral compound Cp*Ir(mu-Cl)(3)Re(CO)(3) (1) undergoes rapid fragmentation in the presence of the unsaturated diphosphine ligand (Z)-Ph2PCH = CHPPh2 to give the mononuclear compounds [Cp*IrCl {(Z)-Ph2PCH = CHPPh2}][Cl] (2) and fac-ClRe(CO)(3)[(Z)-Ph2PCH = CHPPh2] (3). 2 has been characterized by H-1 and P-31 NMR spectroscopy and X-ray diffraction analysis. 2 center dot 2CHCl(3) crystallizes in the monoclinic space group C2/c, a = 35.023 (8) angstrom, b = 10.189 (2) angstrom, c = 24.003 (6) angstrom, b = 103.340 (3), V = 8,335 (3) angstrom 3, Z = 8, and d(calc) = 1.647 Mg/m(3); R = 0.0383, R-w = 0.1135 for 8,178 reflections with I> 2 sigma(I). The Ir(III) center in 2 exhibits a six-coordinate geometry and displays a chelating diphosphine group. Compound 1 reacts with added CO with fragmentation to yield the known compounds Cp*Ir(CO)Cl-2 (4) and ClRe(CO)(5) (5) in near quantitative yield by IR spectroscopy. Using the protocol established by our groups for the synthesis of 1, we have explored the reaction of [Cp*IrCl2](2) with ClMn(CO)(5) as a potential route to Cp*Ir(mu-Cl)(3)Mn(CO)(3); unfortunately, 4 was the only product isolated from this reaction. The solid-state structure of 4 was determined by X-ray diffraction analysis. 4 crystallizes in the triclinic space group P-1, a = 7.4059 (4) angstrom, b = 7.8940 (4) angstrom, c = 11.8488 (7) angstrom, alpha = 80.020 (1), beta = 79.758 (1), gamma = 68.631 (1), V = 630.34 (6) angstrom(3), Z = 2, and d(calc) = 2.246 Mg/m(3); R = 0.0126, R-w = 0.0329 for 2,754 reflections with I> 2 sigma(I). The expected three-legged piano-stool geometry in 4 has been crystallographically confirmed.

Reducing the photo-bleaching effect of a new europium complex embedded in styrene butadiene copolymer

Science.gov (United States)

Jiménez, G. Lesly; Reyes-Rodríguez, J. L.; Padilla, Isela; Alarcón-Flores, G.; Falcony, C.

2018-02-01

A highly luminescent europium complex obtained with two different ligands, succinimide (SI) and 2-thenoyltrifluoroacetone (TTA) , was synthetized with different TTA concentrations. The photoluminescence (PL) emission from these materials corresponds to the characteristic inter-electronic energy level transitions of the Eu3+ ions. However, the excitation spectrum is strongly dependent on the presence of TTA, having an optimum response when 0.75 mmol of this compound is added to the EuL3(H2O)3 complex. The quantum yield obtained by these powders were around 72 % ± 1.7 % indicating an optimum sensitization of these complex. The EuL3 TTA complex with the best PL properties was embedded in a styrene butadiene copolymer (SBC) film, produced by the drop casting method, obtaining similar PL behavior at different concentrations, the highest intensity was observed at 1.2% (w/v) of EuL3 TTA complex and the quantum yield of these composite films was 60.5 % ± 2 % . These films were exposed to continuous UV irradiation and after 141 h no photo-bleaching effect was observed in contrast with the EuL3 TTA complex that exhibited a noticeable photoluminescence intensity degradation at much shorter exposure times. Both the Eu-complexes and the composite films were characterized by FT-IR, XRD, SEM and fluorescence spectroscopy.

Iridium Interfacial Stack - IrIS

Science.gov (United States)

Spry, David

2012-01-01

Iridium Interfacial Stack (IrIS) is the sputter deposition of high-purity tantalum silicide (TaSi2-400 nm)/platinum (Pt-200 nm)/iridium (Ir-200 nm)/platinum (Pt-200 nm) in an ultra-high vacuum system followed by a 600 C anneal in nitrogen for 30 minutes. IrIS simultaneously acts as both a bond metal and a diffusion barrier. This bondable metallization that also acts as a diffusion barrier can prevent oxygen from air and gold from the wire-bond from infiltrating silicon carbide (SiC) monolithically integrated circuits (ICs) operating above 500 C in air for over 1,000 hours. This TaSi2/Pt/Ir/Pt metallization is easily bonded for electrical connection to off-chip circuitry and does not require extra anneals or masking steps. There are two ways that IrIS can be used in SiC ICs for applications above 500 C: it can be put directly on a SiC ohmic contact metal, such as Ti, or be used as a bond metal residing on top of an interconnect metal. For simplicity, only the use as a bond metal is discussed. The layer thickness ratio of TaSi2 to the first Pt layer deposited thereon should be 2:1. This will allow Si from the TaSi2 to react with the Pt to form Pt2Si during the 600 C anneal carried out after all layers have been deposited. The Ir layer does not readily form a silicide at 600 C, and thereby prevents the Si from migrating into the top-most Pt layer during future anneals and high-temperature IC operation. The second (i.e., top-most) deposited Pt layer needs to be about 200 nm to enable easy wire bonding. The thickness of 200 nm for Ir was chosen for initial experiments; further optimization of the Ir layer thickness may be possible via further experimentation. Ir itself is not easily wire-bonded because of its hardness and much higher melting point than Pt. Below the iridium layer, the TaSi2 and Pt react and form desired Pt2Si during the post-deposition anneal while above the iridium layer remains pure Pt as desired to facilitate easy and strong wire-bonding to the Si

FT-IR microspectroscopy characterization of supports for enzyme immobilization in biosensing applications

Science.gov (United States)

Portaccio, M.; Della Ventura, B.; Gabrovska, K.; Marinov, I.; Godjevargova, T.; Mita, D. G.; Lepore, M.

2010-04-01

The investigation of materials suitable for enzyme immobilization in biosensing applications has a widespread interest. There are many studies on physico-chemical properties of these materials at macroscopic level but few studies have been devoted to examine and correlate these properties at microscopic level. FT-IR spectroscopy with Micro-Attenuated Total Reflection (Micro-ATR) approach can be extremely useful for understanding a variety of aspects of materials which can be used for optimising immobilization procedures. Moreover, this experimental approach is particularly simple to use (no sample preparation is required) and minimally invasive. Using a Perkin Elmer Spectrum One FT-IR spectrometer equipped with a mercury-cadmium-telluride detector and a micro-ATR element we investigated different materials used for immobilization procedures with various enzymes widely used for biosensing in environmental and clinical applications. In particular, composite membranes constituted by a chemically modified poly-acrylonitrile (PAN) membrane plus layers of tethered chitosan of different molecular weight have been examined. Also silica gel matrices without and with glucose oxidase have been investigated. Spectra have been analysed and the contribution of principal functional groups has been evidenced.

Investigation of radial propagation of electrostatic fluctuations in the IR-T1 tokamak plasma edge

Energy Technology Data Exchange (ETDEWEB)

Shariatzadeh, R; Ghoranneviss, M; Salem, M K [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University (IAU), PO Box 14665-678, Tehran (Iran, Islamic Republic of); Emami, M, E-mail: rezashariatzadeh@gmail.com [Laser and Optics Research School, NSTRI, AEOI, PO Box 14155-1339, Tehran (Iran, Islamic Republic of)

2011-01-15

The radial propagation of electrostatic fluctuation is considered extremely important for understanding cross-field anomalous transport. In this paper, two arrays of Langmuir probes are used to analyze electrostatic fluctuations in the edge of IR-T1 tokamak plasma in both the radial and the poloidal directions. The propagation characteristics of the floating potential fluctuations are analyzed by the two-point correlation technique. The wavenumber spectrum shows that there is a net radially outward propagation of turbulent fluctuations in the edge and scrape-off layer (SOL) regions. Hence, edge turbulence presumably originates from core fluctuations.

Investigation of radial propagation of electrostatic fluctuations in the IR-T1 tokamak plasma edge

International Nuclear Information System (INIS)

Shariatzadeh, R; Ghoranneviss, M; Salem, M K; Emami, M

2011-01-01

The radial propagation of electrostatic fluctuation is considered extremely important for understanding cross-field anomalous transport. In this paper, two arrays of Langmuir probes are used to analyze electrostatic fluctuations in the edge of IR-T1 tokamak plasma in both the radial and the poloidal directions. The propagation characteristics of the floating potential fluctuations are analyzed by the two-point correlation technique. The wavenumber spectrum shows that there is a net radially outward propagation of turbulent fluctuations in the edge and scrape-off layer (SOL) regions. Hence, edge turbulence presumably originates from core fluctuations.

OH/IR stars in the Galaxy

International Nuclear Information System (INIS)

Baud, B.

1978-01-01

Radio astronomical observations leading to the discovery of 71 OH/IR sources are described in this thesis. These OH/IR sources are characterized by their double peaked OH emission profile at a wavelength of 18 cm and by their strong IR infrared emission. An analysis of the distribution and radial velocities of a number of previously known and new OH/IR sources was performed. The parameter ΔV (the velocity separation between two emission peaks of the 18 cm line profile) was found to be a good criterion for a population classification with respect to stellar age

IR Observations of a Complete Unbiased Sample of Bright Seyfert Galaxies

Science.gov (United States)

Malkan, Matthew; Bendo, George; Charmandaris, Vassilis; Smith, Howard; Spinoglio, Luigi; Tommasin, Silvia

2008-03-01

IR spectra will measure the 2 main energy-generating processes by which galactic nuclei shine: black hole accretion and star formation. Both of these play roles in galaxy evolution, and they appear connected. To obtain a complete sample of AGN, covering the range of luminosities and column-densities, we will combine 2 complete all-sky samples with complementary selections, minimally biased by dust obscuration: the 116 IRAS 12um AGN and the 41 Swift/BAT hard Xray AGN. These galaxies have been extensively studied across the entire EM spectrum. Herschel observations have been requested and will be synergistic with the Spitzer database. IRAC and MIPS imaging will allow us to separate the nuclear and galactic continua. We are completing full IR observations of the local AGN population, most of which have already been done. The only remaining observations we request are 10 IRS/HIRES, 57 MIPS-24 and 30 IRAC pointings. These high-quality observations of bright AGN in the bolometric-flux-limited samples should be completed, for the high legacy value of complete uniform datasets. We will measure quantitatively the emission at each wavelength arising from stars and from accretion in each galactic center. Since our complete samples come from flux-limited all-sky surveys in the IR and HX, we will calculate the bi-variate AGN and star formation Luminosity Functions for the local population of active galaxies, for comparison with higher redshifts.Our second aim is to understand the physical differences between AGN classes. This requires statistical comparisons of full multiwavelength observations of complete representative samples. If the difference between Sy1s and Sy2s is caused by orientation, their isotropic properties, including those of the surrounding galactic centers, should be similar. In contrast, if they are different evolutionary stages following a galaxy encounter, then we may find observational evidence that the circumnuclear ISM of Sy2s is relatively younger.

Ultra-Low-Noise Sub-mm/Far-IR Detectors for Space-Based Telescopes

Science.gov (United States)

Rostem, Karwan

The sub-mm and Far-IR spectrum is rich with information from a wide range of astrophysical sources, including exoplanet atmospheres and galaxies at the peak star formation. In the 10-400 μm range, the spectral lines of important chemical species such H2O, HD, and [OI] can be used to map the formation and evolution of planetary systems. Dust emission in this spectral range is also an important tool for characterizing the morphology of debris disks and interstellar magnetic fields. At larger scales, accessing the formation and distribution of luminous Far-IR and sub-mm galaxies is essential to understanding star formation triggers, as well as the last stages of reionization at z 6. Detector technology is essential to realizing the full science potential of a next-generation Far-IR space telescope (Far-IR Surveyor). The technology gap in large-format, low-noise and ultra-low-noise Far-IR direct detectors is specifically highlighted by NASA's Cosmic Origins Program, and prioritized for development now to enable a flagship mission such as the Far-IR Surveyor that will address the key Cosmic Origins science questions of the next two decades. The detector requirements for a mid-resolution spectrometer are as follows: (1) Highly sensitive detectors with performance approaching 10^-19 - 10^-20 WHz 1/2 for background- limited operation in telescopes with cold optics. (2) Detector time constant in the sub- millisecond range. (3) Scalable architecture to a kilo pixel array with uniform detector characteristics. (4) Compatibility with space operation in the presence of particle radiation. We propose phononic crystals to meet the requirements of ultra-low-noise thermal detectors. By design, a phononic crystal exhibits phonon bandgaps where heat transport is forbidden. The size and location of the bandgaps depend on the elastic properties of the dielectric and the geometry of the phononic unit cell. A wide-bandwidth low-pass thermal filter with a cut-off frequency of 1.5 GHz and

Nearest neighbors EPR superhyperfine interaction in divalent iridium complexes in alkali halide host lattice

International Nuclear Information System (INIS)

Pinhal, N.M.; Vugman, N.V.

1983-01-01

Further splitting of chlorine superhyperfine lines on the EPR spectrum of the [Ir (CN) 4 Cl 2 ] 4 - molecular species in NaCl latice indicates a super-superhyperfine interaction with the nearest neighbors sodium atoms. (Author) [pt

First-principles study on cubic pyrochlore iridates Y2Ir2O7 and Pr2Ir2O7

International Nuclear Information System (INIS)

Ishii, Fumiyuki; Mizuta, Yo Pierre; Kato, Takehiro; Ozaki, Taisuke; Weng Hongming; Onoda, Shigeki

2015-01-01

Fully relativistic first-principles electronic structure calculations based on a noncollinear local spin density approximation (LSDA) are performed for pyrochlore iridates Y 2 Ir 2 O 7 and Pr 2 Ir 2 O 7 . The all-in, all-out antiferromagnetic (AF) order is stablized by the on-site Coulomb repulsion U > U c in the LSDA+U scheme, with U c ∼ 1.1 eV and 1.3 eV for Y 2 Ir 2 O 7 and Pr 2 Ir 2 O 7 , respectively. AF semimetals with and without Weyl points and then a topologically trivial AF insulator successively appear with further increasing U. For U = 1.3 eV, Y 2 Ir 2 O 7 is a topologically trivial narrow-gap AF insulator having an ordered local magnetic moment ∼0.5μ B /Ir, while Pr 2 Ir 2 O 7 is barely a paramagnetic semimetal with electron and hole concentrations of 0.016/Ir, in overall agreements with experiments. With decreasing oxygen position parameter x describing the trigonal compression of IrO 6 octahedra, Pr 2 Ir 2 O 7 is driven through a non-Fermi-liquid semimetal having only an isolated Fermi point of Γ 8 + , showing a quadratic band touching, to a Z 2 topological insulator. (author)

Radioluminescence dating: the IR emission of feldspar

International Nuclear Information System (INIS)

Schilles, Thomas.; Habermann, Jan

2000-01-01

A new luminescence reader for radioluminescence (RL) measurements is presented. The system allows detection of RL emissions in the near infrared region (IR). Basic bleaching properties of the IR-RL emission of feldspars are investigated. Sunlight-bleaching experiments as a test for sensitivity changes are presented. IR-bleaching experiments were carried out to obtain information about the underlying physical processes of the IR-RL emission

Copper(II) complex with 6-methylpyridine-2-carboxyclic acid: Experimental and computational study on the XRD, FT-IR and UV-Vis spectra, refractive index, band gap and NLO parameters.

Science.gov (United States)

Altürk, Sümeyye; Avcı, Davut; Başoğlu, Adil; Tamer, Ömer; Atalay, Yusuf; Dege, Necmi

2018-02-05

Crystal structure of the synthesized copper(II) complex with 6-methylpyridine-2-carboxylic acid, [Cu(6-Mepic) 2 ·H 2 O]·H 2 O, was determined by XRD, FT-IR and UV-Vis spectroscopic techniques. Furthermore, the geometry optimization, harmonic vibration frequencies for the Cu(II) complex were carried out by using Density Functional Theory calculations with HSEh1PBE/6-311G(d,p)/LanL2DZ level. Electronic absorption wavelengths were obtained by using TD-DFT/HSEh1PBE/6-311G(d,p)/LanL2DZ level with CPCM model and major contributions were determined via Swizard/Chemissian program. Additionally, the refractive index, linear optical (LO) and non-nonlinear optical (NLO) parameters of the Cu(II) complex were calculated at HSEh1PBE/6-311G(d,p) level. The experimental and computed small energy gap shows the charge transfer in the Cu(II) complex. Finally, the hyperconjugative interactions and intramolecular charge transfer (ICT) were studied by performing of natural bond orbital (NBO) analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Pamokslo ir eseistikos sąveika Juliaus Sasnausko ir Giedrės Kazlauskaitės eseistikoje

OpenAIRE

Skirmantienė, Daiva

2010-01-01

Jaunosios kartos rašytojų kunigo pamokslininko Juliaus Sasnausko ir pasaulietės Giedrės Kazlauskaitės kūrybos semantinį ir įdėjinį lauką padeda suprasti teologinės literatūros ir literatūrinės teologijos sąveika. Teologinių prasmių paieška jų tekstuose atliepia šiuolaikinio žmogaus pastangas per literatūrą, skelbiančią gyvenamojo laikotarpio aktualijas, rasti kelią į tam tikras krikščioniškąsias tiesas ir bandyti reflektuoti savo tikėjimą bei analizuoti išganymo istoriją. Autorių kūryo...

FAST VARIABILITY AND MILLIMETER/IR FLARES IN GRMHD MODELS OF Sgr A* FROM STRONG-FIELD GRAVITATIONAL LENSING

Energy Technology Data Exchange (ETDEWEB)

Chan, Chi-kwan; Psaltis, Dimitrios; Özel, Feryal; Marrone, Daniel [Steward Observatory and Department of Astronomy, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Medeiros, Lia [Department of Physics, Broida Hall, University of California, Santa Barbara, Santa Barbara, CA 93106 (United States); Sadowski, Aleksander [MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Narayan, Ramesh, E-mail: chanc@email.arizona.edu [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2015-10-20

We explore the variability properties of long, high-cadence general relativistic magnetohydrodynamic (GRMHD) simulations across the electromagnetic spectrum using an efficient, GPU-based radiative transfer algorithm. We focus on both standard and normal evolution (SANE) and magnetically arrested disk (MAD) simulations with parameters that successfully reproduce the time-averaged spectral properties of Sgr A* and the size of its image at 1.3 mm. We find that the SANE models produce short-timescale variability with amplitudes and power spectra that closely resemble those inferred observationally. In contrast, MAD models generate only slow variability at lower flux levels. Neither set of models shows any X-ray flares, which most likely indicates that additional physics, such as particle acceleration mechanisms, need to be incorporated into the GRMHD simulations to account for them. The SANE models show strong, short-lived millimeter/infrared (IR) flares, with short (≲1 hr) time lags between the millimeter and IR wavelengths, that arise from the combination of short-lived magnetic flux tubes and strong-field gravitational lensing near the horizon. Such events provide a natural explanation for the observed IR flares with no X-ray counterparts.

Pullulan-coated phospholipid and Pluronic F68 complex nanoparticles for carrying IR780 and paclitaxel to treat hepatocellular carcinoma by combining photothermal therapy/photodynamic therapy and chemotherapy

Directory of Open Access Journals (Sweden)

Wang D

2017-12-01

Full Text Available Dan Wang,1,* Sipei Zhang,1,* Tao Zhang,1 Guoyun Wan,1 Bowei Chen,1 Qingqing Xiong,2 Jie Zhang,3 Wenxue Zhang,4 Yinsong Wang1 1Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics (Theranostics, School of Pharmacy, Tianjin Medical University, 2Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, 3Surgery Department, 4Radiotherapy Department, Tianjin Medical University General Hospital, Tianjin, China *These authors contributed equally to this work Abstract: IR780, a near-infrared dye, can also be used as a photosensitizer both for photothermal therapy (PTT and photodynamic therapy (PDT. In this study, we designed a simple but effective nanoparticle system for carrying IR780 and paclitaxel, thus hoping to combine PTT/PDT and chemotherapy to treat hepatocellular carcinoma (HCC. This nanosystem, named PDF nanoparticles, consisted of phospholipid/Pluronic F68 complex nanocores and pullulan shells. IR780 and paclitaxel were loaded separately into PDF nanoparticles to form PDFI and PDFP nanoparticles, which had regular sphere shapes and relatively small sizes. Upon near-infrared laser irradiation at 808 nm, PDFI nanoparticles showed strong PTT/PDT efficacy both in vitro and in vivo. In MHCC-97H cells, the combined treatment of PDFI nanoparticles/laser irradiation and PDFP nanoparticles exhibited significant synergistic effects on inhibiting cell proliferation and inducing cell apoptosis and cell cycle arrest at G2/M phase. In MHCC-97H tumor-bearing mice, PDFI nanoparticles exhibited excellent HCC-targeting and accumulating capability after intravenous injection. Furthermore, the combined treatment of PDFI nanoparticles/laser irradiation and PDFP nanoparticles also effectively inhibited the tumor growth and the tumor angiogenesis in MHCC-97H tumor-bearing mice. In summary, we put forward a therapeutic

A high resolution photoemission study of surface core-level shifts in clean and oxygen-covered Ir(2 1 0) surfaces

Energy Technology Data Exchange (ETDEWEB)

Gladys, M.J.; Ermanoski, I.; Jackson, G.; Quinton, J.S.; Rowe, J.E.; Madey, T.E. E-mail: madey@physics.rutgers.edu

2004-04-01

High resolution soft X-ray photoemission electron spectroscopy (SXPS), using synchrotron radiation, is employed to investigate 4f core-level features of four differently-prepared Ir(2 1 0) surfaces: clean planar, oxygen-covered planar, oxygen-induced faceted, and clean faceted surfaces. Surface and bulk peak identifications are supported by measurements at different photon energies (thus probing different electron escape depths) and variable emission angles. Iridium 4f{sub 7/2} photoemission spectra are fitted with Doniach-Sunjic lineshapes. The surface components are identified with core levels positioned at lower binding energies than the bulk components, in contrast to previous reports of binding energy inversion on Ir(1 0 0) (1x1) and (5x1) surfaces. For clean planar Ir(2 1 0) three surface Ir 4f{sub 7/2} features are observed with core-level shifts of -765, -529, and -281 meV, with respect to the bulk; these are associated with the first, second and third layers of atoms, respectively, for atomically rough Ir(2 1 0). Adsorption of oxygen onto the planar Ir(2 1 0) surface is found to cause a suppression and shift of the surface features to higher binding energies. Annealing at T{>=}600 K in oxygen produces a faceted surface as verified by low energy electron diffraction (LEED). A comparison of planar and faceted oxygen-covered surfaces reveals minor differences in the normal emission SXPS spectra, while grazing emission spectra exhibit differences. The SXPS spectrum of the clean, faceted Ir(2 1 0) exhibits small differences in comparison to the clean planar case, with surface features having binding energy shifts of -710, -450, and -230 meV.

Complexity and wide range of neuromyelitis optica spectrum disorders: more than typical manifestations

Science.gov (United States)

Han, Jinming; Yang, Meng-ge; Zhu, Jie; Jin, Tao

2017-01-01

Neuromyelitis optica (NMO), considered to be mediated by autoantibodies, often cause severely disabling disorders of the central nervous system, and predominantly cause optic nerve damage and longitudinally extensive transverse myelitis. Remarkable progress has been made in deciphering NMO pathogenesis during the past decade. In 2015, the International Panel for NMO Diagnosis proposed the unifying term “NMO spectrum disorders” (NMOSD) and the updated NMOSD criteria reflects a wide range of disease and maintains reasonable specificity. Moreover, cumulative findings have indicated that NMOSD are frequently associated with multiple autoimmune diseases, thereby presenting complex clinical symptoms that make this disease more difficult to recognize. Notably, most neurologists do not heed these symptoms or comorbid conditions in patients with NMOSD. Whereas previous reviews have focused on pathogenesis, treatment, and prognosis in NMOSD, we summarize the present knowledge with particular emphasis on atypical manifestations and autoimmune comorbidities in patients with NMOSD. Furthermore, we emphasized the identification of these atypical characteristics to enable a broader and better understanding of NMOSD, and improve early accurate diagnosis and therapeutic decision making. PMID:29118581

β-Isocyanoalanine as an IR probe: comparison of vibrational dynamics between isonitrile and nitrile-derivatized IR probes.

Science.gov (United States)

Maj, Michał; Ahn, Changwoo; Kossowska, Dorota; Park, Kwanghee; Kwak, Kyungwon; Han, Hogyu; Cho, Minhaeng

2015-05-07

An infrared (IR) probe based on isonitrile (NC)-derivatized alanine 1 was synthesized and the vibrational properties of its NC stretching mode were investigated using FTIR and femtosecond IR pump-probe spectroscopy. It is found that the NC stretching mode is very sensitive to the hydrogen-bonding ability of solvent molecules. Moreover, its transition dipole strength is larger than that of nitrile (CN) in nitrile-derivatized IR probe 2. The vibrational lifetime of the NC stretching mode is found to be 5.5 ± 0.2 ps in both D2O and DMF solvents, which is several times longer than that of the azido (N3) stretching mode in azido-derivatized IR probe 3. Altogether these properties suggest that the NC group can be a very promising sensing moiety of IR probes for studying the solvation structure and dynamics of biomolecules.

Feeding of the 1 1/2- isomers in stable Ir and Au isotopes

Energy Technology Data Exchange (ETDEWEB)

Fotiadis, Nikolaos [Los Alamos National Laboratory; Nelson, Ronald O [Los Alamos National Laboratory; Devlin, Matthew [Los Alamos National Laboratory; Holloway, Shannon T [Los Alamos National Laboratory; Kawano, Toshihiko [Los Alamos National Laboratory; Talou, Patrick [Los Alamos National Laboratory; Chadwick, Mark B [Los Alamos National Laboratory; Becker, John A [LLNL; Garrett, Paul E [U GUELPH, CANADA

2008-01-01

Excited states were studied and absolute partial {gamma}-ray cross sections were measured using the ({eta}, {eta}'{gamma}) reaction in {sup 191}Ir, {sup 193}Ir and {sup 197}Au. A Compton-suppressed germanium-detector array (GEANIE) for {gamma}-ray spectroscopy and the broad-spectrum pulsed neutron source of the Los Alamos Neutron Science Center's WNR facility were used for the measurement. The energy of the incident neutrons was determined using the time-of-flight technique. Absolute partial {gamma}-ray cross sections were measured up to incident neutron energy of 20 MeV for several transitions feeding directly the 1 1/2- isomers and ground states in {sup 191}Ir, {sup 193}Ir and {sup 197}Au. The feeding of the 1 1/2- isomers, which originate from the odd proton occupying the h{sub 1 1/2} orbital, was found for the three targets to be very similar and increasing relative to the feeding of the corresponding ground state with increasing neutron energy up to E{sub n} {approx} 10 MeV. Above this neutron energy the opening of the (n, 2{sub n}) reaction channel strongly affects the population of the isomers and leads to a decrease of their relative population compared to the population of the ground states. The experimental results are compared with theoretical predictions from the GNASH reaction model calculation implementing a version of the spin distribution for the pre-equilibrium reaction piece with either a compound nucleus spin distribution (CN-GNASH) or a Feshbach-Kerman-Koonin (FKK-GNASH) quantum mechanical spin distribution. The effects of the spin cutoff parameter values on the population of states are examined. Evidence is presented that FKK-GNASH provides a description of the experimental data that mitigates the need for adjustment of the level density parameter to fit the data.

Synthesis, Molecular Structure and Cytotoxicity of Molecular Materials Based on Water Soluble Half-Sandwich Rh(III) and Ir(III) Tetranuclear Metalla-Cycles

Science.gov (United States)

Gupta, Gajendra; Murray, Benjamin S.; Dyson, Paul J.; Therrien, Bruno

2013-01-01

The neutral dinuclear complexes [(η5-C5Me5)2Rh2(μ-dhnq)Cl2] (1) and [(η5-C5Me5)2Ir2(μ-dhnq)Cl2] (2) (dhnqH2 = 5,8-dihydroxy-1,4-naphthoquinone) were obtained from the reaction of [(η5-C5Me5)M(μ-Cl)Cl]2 (M = Rh, Ir) with dhnqH2 in the presence of CH3COONa. Treatment of 1 or 2 in methanol with linear ditopic ligands L (L = pyrazine, 4,4′-bipyridine or 1,2-bis(4-pyridyl)ethylene), in the presence of AgCF3SO3, affords the corresponding tetranuclear metalla-rectangles [(η5-C5Me5)4M4(μ-dhnq)2(μ-L)2]4+ (L = pyrazine, M = Rh, 3; M = Ir, 4; L = 4,4′-bipyridine, M = Rh, 5; M = Ir, 6; L = 1,2-bis(4-pyridyl)ethylene, M = Rh, 7; M = Ir, 8). All complexes were isolated as their triflate salts and were fully characterized by infrared, 1H and 13C NMR spectroscopy, and some representative complexes by single-crystal X-ray structure analysis. The X-ray structures of 3, 5 and 6 confirm the formation of the tetranuclear metalla-cycles, and suggest that complexes 5 and 6 possess a cavity of sufficient size to encapsulate small guest molecules. In addition, the antiproliferative activity of the metalla-cycles 3–8 was evaluated against the human ovarian A2780 (cisplatin sensitive) and A2780cisR (cisplatin resistant) cancer cell lines and on non-tumorigenic human embryonic kidney HEK293 cells. All cationic tetranuclear metalla-rectangles were found to be highly cytotoxic, with IC50 values in the low micromolar range. PMID:28788394

Synthesis, Molecular Structure and Cytotoxicity of Molecular Materials Based on Water Soluble Half-Sandwich Rh(III and Ir(III Tetranuclear Metalla-Cycles

Directory of Open Access Journals (Sweden)

Gajendra Gupta

2013-11-01

Full Text Available The neutral dinuclear complexes [(η5-C5Me52Rh2(μ-dhnqCl2] (1 and [(η5-C5Me52Ir2(μ-dhnqCl2] (2 (dhnqH2 = 5,8-dihydroxy-1,4-naphthoquinone were obtained from the reaction of [(η5-C5Me5M(μ-ClCl]2 (M = Rh, Ir with dhnqH2 in the presence of CH3COONa. Treatment of 1 or 2 in methanol with linear ditopic ligands L (L = pyrazine, 4,4′-bipyridine or 1,2-bis(4-pyridylethylene, in the presence of AgCF3SO3, affords the corresponding tetranuclear metalla-rectangles [(η5-C5Me54M4(μ-dhnq2(μ-L2]4+ (L = pyrazine, M = Rh, 3; M = Ir, 4; L = 4,4′-bipyridine, M = Rh, 5; M = Ir, 6; L = 1,2-bis(4-pyridylethylene, M = Rh, 7; M = Ir, 8. All complexes were isolated as their triflate salts and were fully characterized by infrared, 1H and 13C NMR spectroscopy, and some representative complexes by single-crystal X-ray structure analysis. The X-ray structures of 3, 5 and 6 confirm the formation of the tetranuclear metalla-cycles, and suggest that complexes 5 and 6 possess a cavity of sufficient size to encapsulate small guest molecules. In addition, the antiproliferative activity of the metalla-cycles 3–8 was evaluated against the human ovarian A2780 (cisplatin sensitive and A2780cisR (cisplatin resistant cancer cell lines and on non-tumorigenic human embryonic kidney HEK293 cells. All cationic tetranuclear metalla-rectangles were found to be highly cytotoxic, with IC50 values in the low micromolar range.

Joint IAEA/NEA IRS guidelines

International Nuclear Information System (INIS)

1997-01-01

The Incident Reporting System (IRS) is an international system jointly operated by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD/NEA). The fundamental objective of the IRS is to contribute to improving the safety of commercial nuclear power plants (NPPs) which are operated worldwide. This objective can be achieved by providing timely and detailed information on both technical and human factors related to events of safety significance which occur at these plants. The purpose of these guidelines, which supersede the previous IAEA Safety Series No. 93 (Part II) and the NEA IRS guidelines, is to describe the system and to give users the necessary background and guidance to enable them to produce IRS reports meeting a high standard of quality while retaining the high efficiency of the system expected by all Member States operating nuclear power plants

Energetic mid-IR femtosecond pulse generation by self-defocusing soliton-induced dispersive waves in a bulk quadratic nonlinear crystal

DEFF Research Database (Denmark)

Zhou, Binbin; Guo, Hairun; Bache, Morten

2015-01-01

Generating energetic femtosecond mid-IR pulses is crucial for ultrafast spectroscopy, and currently relies on parametric processes that, while efficient, are also complex. Here we experimentally show a simple alternative that uses a single pump wavelength without any pump synchronization and with...... by using large-aperture crystals. The technique can readily be implemented with other crystals and laser wavelengths, and can therefore potentially replace current ultrafast frequency-conversion processes to the mid-IR....... and without critical phase-matching requirements. Pumping a bulk quadratic nonlinear crystal (unpoled LiNbO3 cut for noncritical phase-mismatched interaction) with sub-mJ near-IR 50-fs pulses, tunable and broadband (∼ 1,000 cm−1) mid-IR pulses around 3.0 μm are generated with excellent spatio-temporal pulse...... quality, having up to 10.5 μJ energy (6.3% conversion). The mid-IR pulses are dispersive waves phase-matched to near-IR self-defocusing solitons created by the induced self-defocusing cascaded nonlinearity. This process is filament-free and the input pulse energy can therefore be scaled arbitrarily...

Iridium complexes for electrocatalysis

Science.gov (United States)

Sheehan, Stafford Wheeler; Hintermair, Ulrich; Thomsen, Julianne M; Brudvig, Gary W; Crabtree, Robert H

2017-10-17

Solution-phase (e.g., homogeneous) or surface-immobilized (e.g., heterogeneous) electrode-driven oxidation catalysts based on iridium coordination compounds which self-assemble upon chemical or electrochemical oxidation of suitable precursors and methods of making and using thereof are. Iridium species such as {[Ir(LX).sub.x(H.sub.2O).sub.y(.mu.-O)].sub.z.sup.m+}.sub.n wherein x, y, m are integers from 0-4, z and n from 1-4 and LX is an oxidation-resistant chelate ligand or ligands, such as such as 2(2-pyridyl)-2-propanolate, form upon oxidation of various molecular iridium complexes, for instance [Cp*Ir(LX)OH] or [(cod)Ir(LX)] (Cp*=pentamethylcyclopentadienyl, cod=cis-cis,1,5-cyclooctadiene) when exposed to oxidative conditions, such as sodium periodate (NaIO.sub.4) in aqueous solution at ambient conditions.

CCD and IR array controllers

Science.gov (United States)

Leach, Robert W.; Low, Frank J.

2000-08-01

A family of controllers has bene developed that is powerful and flexible enough to operate a wide range of CCD and IR focal plane arrays in a variety of ground-based applications. These include fast readout of small CCD and IR arrays for adaptive optics applications, slow readout of large CCD and IR mosaics, and single CCD and IR array operation at low background/low noise regimes as well as high background/high speed regimes. The CCD and IR controllers have a common digital core based on user- programmable digital signal processors that are used to generate the array clocking and signal processing signals customized for each application. A fiber optic link passes image data and commands to VME or PCI interface boards resident in a host computer to the controller. CCD signal processing is done with a dual slope integrator operating at speeds of up to one Megapixel per second per channel. Signal processing of IR arrays is done either with a dual channel video processor or a four channel video processor that has built-in image memory and a coadder to 32-bit precision for operating high background arrays. Recent developments underway include the implementation of a fast fiber optic data link operating at a speed of 12.5 Megapixels per second for fast image transfer from the controller to the host computer, and supporting image acquisition software and device drivers for the PCI interface board for the Sun Solaris, Linux and Windows 2000 operating systems.

Įvairialyčiai lantano ir mangano oksido ir multiferoinio bismuto ferito heterodariniai

Directory of Open Access Journals (Sweden)

Bonifacas VENGALIS

2011-11-01

Full Text Available Pastaruoju metu naujų elektronikos prietaisų gamyboje buvo pasiekta didelė pažanga auginant, tyrinėjant ir pritaikant plonasluoksnes struktūras, sudarytas iš įvairių daugiakomponenčių funkcinių oksidų. Šiai oksidų grupei priklauso superlaidieji kupratai, mangano oksidai (manganitai, pasižymintys magnetovaržos reiškiniu, taip pat kiti feromagnetiniai, feroelektriniai, multiferoiniai oksidai. Manganitams (jų bendra formulė Ln1-xAxMnO3, kur Ln = La, Nd,..., o A - dvivalentis katijonas, toks kaip Ba, Sr ar Ca skiriama daug dėmesio dėl jų įdomių elektrinių savybių bei tinkamumo įvairiems spintronikos prietaisams kurti. Multiferoikai  (feroelektriniai feromagnetai pasižymi magnetoelektriniu efektu, duodančiu unikalią galimybę elektrinėms ir magnetinėms medžiagos savybėms valdyti panaudoti elektrinius ir magnetinius laukus. Bismuto feritas BiFeO3 (BFO, turintis romboedriškai deformuotą perovskito struktūrą, šiuo metu yra vienas labiausiai tyrinėjamų šios klasės junginių. Organiniai puslaidininkiai (OP taip pat atveria daug naujų galimybių elektronikai. Jų pranašumas yra didelė organinių junginių įvairovė ir palyginti paprasta ir pigi plonų sluoksnių gamybos technologija. Be to, OP pasižymi neįprastai didelėmis sukinių relaksacijos laiko vertėmis, todėl ateityje jie gali būti naudojami naujiems spintronikos prietaisams gaminti. Šiame straipsnyje apžvelgiami pastarųjų metų darbo autorių ir jų kolegų atlikti anksčiau minėtų medžiagų tyrimai. Daugiausia dėmesio skiriama magnetovaržinėmis savybėmis pasižyminčių lantano ir mangano oksidų (manganitų bei multiferoinio  BiFeO3 (BFO junginio plonųjų sluoksnių ir heterodarinių auginimui, tarpfazinių ribų tarp minėtų oksidų, laidžiojo SrTiO3 ir organinio puslaidininkio (Alq3 sudarymui, taip pat elektrinėms heterodarinių savybėms. Plonieji La2/3A1/3MnO3 (A = Ca, Sr, Ba, Ce sluoksniai, kurių storis d

Complexes of Sm(III) and Dy(III) with piperazines

Energy Technology Data Exchange (ETDEWEB)

Manhas, B S; Trikha, A K [Punjabi Univ., Patiala (India). Dept. of Chemistry; Singh, M [Guru Nanak Dev Univ., Amritsar (India). Dept. of Chemistry

1981-09-01

Complexes of SmCl/sub 3/, DyCl/sub 3/, Sm(NO/sub 3/)/sub 3/ and Dy(NO/sub 3/) with piperazine, N-methylpiperazine, 2-methylpiperazine, N-phenyl-piperazine and N, N'-dimethyl-piperazine have been prepared and characterized on the basis of elemental analyses, IR and electronic reflectance spectra and magnetic susceptibility measurements. IR data indicate that the ligands are coordinated in the chair conformation giving polymeric bridged complexes and that the nitrate group is bidentate. Coordination numbers from 6 to 12 are proposed for the lanthanide ions.

General report IRS-literature 1965-1976

International Nuclear Information System (INIS)

Schulz, W.

1976-12-01

The Institut fuer Reaktorsicherheit der TUeV e.V. (IRS) is of central importance in matters of licensing. It was jointly founded in 1965 by the eleven TUeVs of the Federal Republic of Germany and West-Berlin, by the Germanischer Lloyd and the then Federal Ministry for Scientific Research. After 12 sucsessful years the IRS will terminate its activities on December 31st, 1976, and together with the Laboratorium fuer Reaktorregelung und Anlagensicherung (LRA) at the TU Munich, Garching, it will be from January 1st, 1977 onwards part of the Gesellschaft fuer Reaktorsicherheit (GRS) mbH, a newly founded corporation. The activities of IRS and LRA will be continued by the GRS starting from January 1st, 1977. All IRS' report series and information services listed in this report are thus running out. The new corporation will build up its publications on the basis of the experience gained by IRS and LRA. (orig.) [de

High-efficiency red-light emission from polyfluorenes grafted with cyclometalated iridium complexes and charge transport moiety.

Science.gov (United States)

Chen, Xiwen; Liao, Jin-Long; Liang, Yongmin; Ahmed, M O; Tseng, Hao-En; Chen, Show-An

2003-01-22

We report a new route for the design of electroluminescent polymers by grafting high-efficiency phosphorescent organometallic complexes as dopants and charge transport moieties onto alky side chains of fully conjugated polymers for polymer light-emitting diodes (PLED) with single layer/single polymers. The polymer system studied involves polyfluorene (PF) as the base conjugated polymer, carbazole (Cz) as the charge transport moiety and a source for green emission by forming an electroplex with the PF main chain, and cyclometalated iridium (Ir) complexes as the phosphorescent dopant. Energy transfer from the green Ir complex or an electroplex formed between the fluorene main chain and side-chain carbazole moieties, in addition to that from the PF main chain, to the red Ir complex can significantly enhance the device performance, and a red light-emitting device with the high efficiency 2.8 cd/A at 7 V and 65 cd/m2, comparable to that of the same Ir complex-based OLED, and a broad-band light-emitting device containing blue, green, and red peaks (2.16 cd/A at 9 V) are obtained.

Power scaling of ultrafast mid-IR source enabled by high-power fiber laser technology

Energy Technology Data Exchange (ETDEWEB)

Zhou, Gengji

2017-11-15

Ultrafast laser sources with high repetition-rate (>10 MHz) and tunable in the mid-infrared (IR) wavelength range of 7-18 μm hold promise for many important spectroscopy applications. Currently, these ultrafast mid- to longwavelength-IR sources can most easily be achieved via difference-frequency generation (DFG) between a pump beam and a signal beam. However, current ultrafast mid- to longwavelength-IR sources feature a low average power, which limits their applications. In this thesis, we propose and demonstrate a novel approach to power scaling of DFG-based ultrafast mid-IR laser sources. The essence of this novel approach is the generation of a high-energy signal beam. Both the pump beam and the signal beam are derived from a home-built Yb-fiber laser system that emits 165-fs pulses centered at 1035 nm with 30-MHz repetition rate and 14.5-W average power (corresponding to 483-nJ pulse energy). We employ fiber-optic self-phase modulation (SPM) to broaden the laser spectrum and generate isolated spectral lobes. Filtering the rightmost spectral lobe leads to femtosecond pulses with >10 nJ pulse energy. Tunable between 1.1-1.2 μm, this SPM-enabled ultrafast source exhibits ∝100 times higher pulse energy than can be obtained from Raman soliton sources in this wavelength range. We use this SPM-enabled source as the signal beam and part of the Yb-fiber laser output as the pump beam. By performing DFG in GaSe crystals, we demonstrate that power scaling of a DFG-based mid-IR source can be efficiently achieved by increasing the signal energy. The resulting mid-IR source is tunable from 7.4 μm to 16.8 μm. Up to 5.04-mW mid-IR pulses centered at 11 μm are achieved. The corresponding pulse energy is 167 pJ, representing nearly one order of magnitude improvement compared with other reported DFG-based mid-IR sources at this wavelength. Despite of low pulse energy, Raman soliton sources have become a popular choice as the signal source. We carry out a detailed study on

Power scaling of ultrafast mid-IR source enabled by high-power fiber laser technology

International Nuclear Information System (INIS)

Zhou, Gengji

2017-11-01

Ultrafast laser sources with high repetition-rate (>10 MHz) and tunable in the mid-infrared (IR) wavelength range of 7-18 μm hold promise for many important spectroscopy applications. Currently, these ultrafast mid- to longwavelength-IR sources can most easily be achieved via difference-frequency generation (DFG) between a pump beam and a signal beam. However, current ultrafast mid- to longwavelength-IR sources feature a low average power, which limits their applications. In this thesis, we propose and demonstrate a novel approach to power scaling of DFG-based ultrafast mid-IR laser sources. The essence of this novel approach is the generation of a high-energy signal beam. Both the pump beam and the signal beam are derived from a home-built Yb-fiber laser system that emits 165-fs pulses centered at 1035 nm with 30-MHz repetition rate and 14.5-W average power (corresponding to 483-nJ pulse energy). We employ fiber-optic self-phase modulation (SPM) to broaden the laser spectrum and generate isolated spectral lobes. Filtering the rightmost spectral lobe leads to femtosecond pulses with >10 nJ pulse energy. Tunable between 1.1-1.2 μm, this SPM-enabled ultrafast source exhibits ∝100 times higher pulse energy than can be obtained from Raman soliton sources in this wavelength range. We use this SPM-enabled source as the signal beam and part of the Yb-fiber laser output as the pump beam. By performing DFG in GaSe crystals, we demonstrate that power scaling of a DFG-based mid-IR source can be efficiently achieved by increasing the signal energy. The resulting mid-IR source is tunable from 7.4 μm to 16.8 μm. Up to 5.04-mW mid-IR pulses centered at 11 μm are achieved. The corresponding pulse energy is 167 pJ, representing nearly one order of magnitude improvement compared with other reported DFG-based mid-IR sources at this wavelength. Despite of low pulse energy, Raman soliton sources have become a popular choice as the signal source. We carry out a detailed study on

Possibilities of the observation of the discrete spectrum of the water dimer at equilibrium in millimeter-wave band

International Nuclear Information System (INIS)

Krupnov, A.F.; Tretyakov, M.Yu.; Leforestier, C.

2009-01-01

Attempts of experimental observations of the water dimer spectrum at equilibrium conditions have lasted for more than 40 years since the dimeric hypothesis for extra absorption, but have not yielded any positive confirmed result. In the present paper a new approach is considered: using a high-resolution millimeter-wave spectrum of the water dimer at equilibrium, calculated by a rigorous fully quantum method, we show the potential existence of discernible spectral series of discrete features of the water dimer, which correspond to J+1 1 symmetry, already observed in cold molecular beam experiments and having, therefore, well-defined positions. The intensity of spectral series and contrast to the remaining continuum-like spectrum of the dimer are calculated and compared with the monomer absorption. The suitability of two types of microwave spectrometers for observing these series is considered. The collisional line-width of millimeter lines of the dimer at equilibrium is estimated and the width of IR dimer bands is discussed. It is pointed out that the large width of IR dimer bands may pose difficulties for their reliable observation and conclusive separation from the rest of absorption in water vapor. This situation contrasts with the suggested approach of dimer detection in millimeter-waves.

Dynamical versus diffraction spectrum for structures with finite local complexity

NARCIS (Netherlands)

Baake, Michael; Lenz, Daniel; van Enter, Aernout

2015-01-01

It is well known that the dynamical spectrum of an ergodic measure dynamical system is related to the diffraction measure of a typical element of the system. This situation includes ergodic subshifts from symbolic dynamics as well as ergodic Delone dynamical systems, both via suitable embeddings.

The structure of salt bridges between Arg(+) and Glu(-) in peptides investigated with 2D-IR spectroscopy: Evidence for two distinct hydrogen-bond geometries.

Science.gov (United States)

Huerta-Viga, Adriana; Amirjalayer, Saeed; Domingos, Sérgio R; Meuzelaar, Heleen; Rupenyan, Alisa; Woutersen, Sander

2015-06-07

Salt bridges play an important role in protein folding and in supramolecular chemistry, but they are difficult to detect and characterize in solution. Here, we investigate salt bridges between glutamate (Glu(-)) and arginine (Arg(+)) using two-dimensional infrared (2D-IR) spectroscopy. The 2D-IR spectrum of a salt-bridged dimer shows cross peaks between the vibrational modes of Glu(-) and Arg(+), which provide a sensitive structural probe of Glu(-)⋯Arg(+) salt bridges. We use this probe to investigate a β-turn locked by a salt bridge, an α-helical peptide whose structure is stabilized by salt bridges, and a coiled coil that is stabilized by intra- and intermolecular salt bridges. We detect a bidentate salt bridge in the β-turn, a monodentate one in the α-helical peptide, and both salt-bridge geometries in the coiled coil. To our knowledge, this is the first time 2D-IR has been used to probe tertiary side chain interactions in peptides, and our results show that 2D-IR spectroscopy is a powerful method for investigating salt bridges in solution.

Complex magnetism of the Fe monolayer on Ir(111)

International Nuclear Information System (INIS)

Bergmann, Kirsten von; Heinze, Stefan; Bode, Matthias; Bihlmayer, Gustav; Bluegel, Stefan; Wiesendanger, Roland

2007-01-01

The electronic and magnetic properties of Fe on Ir(111) have been investigated experimentally by spin-polarized scanning tunneling microscopy (SP-STM) and theoretically by first-principles calculations based on density functional theory. While the growth of an Fe monolayer is in-plane commensurate, deposition of a double-layer shows a rearrangement of atoms due to strain relief accompanied by local variations of the electronic structure. Both stackings of the monolayer, i.e. face centered cubic (fcc) and hexagonal closed packed (hcp), are observed experimentally. The magnetic structure of both types is imaged with SP-STM. From these experiments, we propose a nanoscale magnetic mosaic structure for the fcc-stacking with 15 atoms in the unit cell. For hcp-stacking, the tunneling spectra are similar to the fcc case, however, the magnetic contrast in the SP-STM images is not as obvious. In our first-principles calculations, a collinear antiferromagnetic (AFM) state with a 15 atom in-plane unit cell (AFM 7 : 8 state) is found to be more favorable than the ferromagnetic state for both fcc- and hcp-stacking. Calculated SP-STM images and spectra are also in good agreement with the experimental data for the fcc case. We performed spin spiral calculations which are mapped to a classical Heisenberg model to obtain the exchange-interaction constants. From these calculations, it is found that the AFM 7 : 8 state is energetically more favorable than all solutions of the classical Heisenberg model. While the obtained magnetic exchange constants are rather similar for the fcc and hcp stacking, a comparison with the experiments indicates that competing interactions could be responsible for the differences observed in the magnetically sensitive measurements

Complexity measures of music

Science.gov (United States)

Pease, April; Mahmoodi, Korosh; West, Bruce J.

2018-03-01

We present a technique to search for the presence of crucial events in music, based on the analysis of the music volume. Earlier work on this issue was based on the assumption that crucial events correspond to the change of music notes, with the interesting result that the complexity index of the crucial events is mu ~ 2, which is the same inverse power-law index of the dynamics of the brain. The search technique analyzes music volume and confirms the results of the earlier work, thereby contributing to the explanation as to why the brain is sensitive to music, through the phenomenon of complexity matching. Complexity matching has recently been interpreted as the transfer of multifractality from one complex network to another. For this reason we also examine the mulifractality of music, with the observation that the multifractal spectrum of a computer performance is significantly narrower than the multifractal spectrum of a human performance of the same musical score. We conjecture that although crucial events are demonstrably important for information transmission, they alone are not suficient to define musicality, which is more adequately measured by the multifractality spectrum.

Activation of carbon monoxide by (Me3tpa)Rh and (Me3tpa)Ir

NARCIS (Netherlands)

Dzik, W.I.; Smits, J.M.M.; Reek, J.N.H.; de Bruin, B.

2009-01-01

Cationic iridium and rhodium carbonyl complexes supported with the tetradentate N-donor ligand Me(3)tpa (Me(3)tPa = N,N,N-tri(6-methyl-2-pyridylmethyl)amine) were synthesized. Their structures were investigated using X-ray diffraction, NMR, and IR, and their redox properties were probed using cyclic

Laser Spectroscopic and Theoretical Studies of Encapsulation Complexes of Calix[4]arene

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Shohei; Inokuchi, Yoshiya; Ebata, Takayuki; Apra, Edoardo; Xantheas, Sotiris S.

2011-10-13

The complexes between the host calix[4]arene (C4A) and various guest molecules such as NH3, N2, CH4, and C2H2 have been investigated via experimental and theoretical methods. The S1-S0 electronic spectra of these guest-host complexes are observed by mass-selected resonant two-photon ionization (R2PI) and laser induced fluorescence (LIF) spectroscopy. The infrared (IR) spectra of the complexes formed in molecular beams are obtained by IR-UV double resonance (IR-UV DR) and IR photodissociation (IRPD) spectroscopy. The supramolecular structures of the complexes are investigated by electronic structure methods (density functional and second order perturbation theory). The current results for the various molecular guests are put in perspective with the previously reported ones for the C4A-Rare Gas (Rg) (Phys. Chem. Chem. Phys. 2007, 126, 141101) and C4A-H2O complexes (J. Phys. Chem. A, 2010, 114, 2967). The electronic spectra of the complexes of C4A with N2, CH4 and C2H2 exhibit red-shifts of similar magnitudes with the ones observed for the C4A-Rg complexes, whereas the complexes of C4A with H2O and NH3 show much larger red-shifts. Most of the IR-UV DR spectra of the complexes, except for C4A-C2H2, show a broad hydrogen bonded OH stretching band with a peak at ~3160 cm-1. The analysis of the experimental results, in agreement with the ones resulted from the electronic structure calculations, suggest that C4A preferentially forms endo-complexes with all the guest species reported in this study. We discuss the similarities and differences of the structures, binding energies and the nature of the interaction between the C4A host and the various guest species. This work was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy

Auditory spatial attention to speech and complex non-speech sounds in children with autism spectrum disorder.

Science.gov (United States)

Soskey, Laura N; Allen, Paul D; Bennetto, Loisa

2017-08-01

One of the earliest observable impairments in autism spectrum disorder (ASD) is a failure to orient to speech and other social stimuli. Auditory spatial attention, a key component of orienting to sounds in the environment, has been shown to be impaired in adults with ASD. Additionally, specific deficits in orienting to social sounds could be related to increased acoustic complexity of speech. We aimed to characterize auditory spatial attention in children with ASD and neurotypical controls, and to determine the effect of auditory stimulus complexity on spatial attention. In a spatial attention task, target and distractor sounds were played randomly in rapid succession from speakers in a free-field array. Participants attended to a central or peripheral location, and were instructed to respond to target sounds at the attended location while ignoring nearby sounds. Stimulus-specific blocks evaluated spatial attention for simple non-speech tones, speech sounds (vowels), and complex non-speech sounds matched to vowels on key acoustic properties. Children with ASD had significantly more diffuse auditory spatial attention than neurotypical children when attending front, indicated by increased responding to sounds at adjacent non-target locations. No significant differences in spatial attention emerged based on stimulus complexity. Additionally, in the ASD group, more diffuse spatial attention was associated with more severe ASD symptoms but not with general inattention symptoms. Spatial attention deficits have important implications for understanding social orienting deficits and atypical attentional processes that contribute to core deficits of ASD. Autism Res 2017, 10: 1405-1416. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Metal oxalate complexes as novel inorganic dopants: Studies on ...

Indian Academy of Sciences (India)

Unknown

UV-visible and IR spectral features not only confirmed the polyaniline doping by complex anions but also substantiated ... MoS3 dopant. Although inorganic metal complexes bear- ... distilled water and then with methanol and acetone until.

Synthesis, crystal structures, and urease inhibition of an acetohydroxamate-coordinated oxovanadium(V) complex derived from N'-(3-bromo-2-hydroxybenzylidene)-4-methoxybenzohydrazide.

Science.gov (United States)

Qu, Dan; Niu, Fang; Zhao, Xinlu; Yan, Ke-Xiang; Ye, Yu-Ting; Wang, Jia; Zhang, Mei; You, Zhonglu

2015-05-01

A new benzohydrazone compound N'-(3-bromo-2-hydroxybenzylidene)-4-methoxybenzohydrazide (H₂L) was prepared. Reaction of H₂L and acetohydroxamic acid (HAHA) with VO(acac)₂ in methanol gave the complex [VOL(AHA)]. Both H₂L and the oxovanadium complex were characterized by elemental analysis, IR, UV-vis and (1)H NMR spectra, and single crystal X-ray diffraction. H₂L was also characterized by high-resolution mass spectrum. Thermal analysis of the oxovanadium complex was carried out. The benzohydrazone ligand, in its dianionic form, coordinates to V atom through the phenolate oxygen, imino nitrogen and enolate oxygen. The acetohydroxamic acid coordinates to V atom through the carbonyl oxygen and deprotonated hydroxyl oxygen. The V atom is in octahedral coordination. H₂L, HAHA and the oxovanadium complex were tested for their urease inhibitory activities. The percent inhibition at concentration of 100 μmol·L(-1) on Helicobacter pylori urease is 78% for the oxovanadium complex. The IC₅₀ value for the complex is 36.5 μmol·L(-1). Molecular docking study was performed to study the inhibition. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optical and near-IR study of LMC HII region N11AB

International Nuclear Information System (INIS)

Lee, M.G.

1990-01-01

N11 (DEM 34), complex HII region located about 4 degrees from the center of the LMC bar, is a very interesting giant interstellar shell. It has a complicated structure and motion. It is located on the edge of an HI concentration. This is the progress report of the study of its two components, A and B at the optical and near-IR wavelengths to investigate stars, dust and ionized gas associated with them. N11A is a compact high-excitation blob and N11B is a bright HII region in this complex, which embeds OB association Lucke-Hodge 10

Mapping the spectral phase of isolated attosecond pulses by extreme-ultraviolet emission spectrum.

Science.gov (United States)

Liu, Candong; Zeng, Zhinan; Li, Ruxin; Xu, Zhizhan; Nisoli, Mauro

2015-04-20

An all-optical method is proposed for the measurement of the spectral phase of isolated attosecond pulses. The technique is based on the generation of extreme-ultraviolet (XUV) radiation in a gas by the combination of an attosecond pulse and a strong infrared (IR) pulse with controlled electric field. By using a full quantum simulation, we demonstrate that, for particular temporal delays between the two pulses, the IR field can drive back to the parent ions the photoelectrons generated by the attosecond pulse, thus leading to the generation of XUV photons. It is found that the generated XUV spectrum is notably sensitive to the chirp of the attosecond pulse, which can then be reliably retrieved. A classical quantum-path analysis is further used to quantitatively explain the main features exhibited in the XUV emission.

Complex compound polyvinyl alcohol-titanic acid/titanium dioxide

Science.gov (United States)

Prosanov, I. Yu.

2013-02-01

A complex compound polyvinyl alcohol-titanic acid has been produced and investigated by means of IR and Raman spectroscopy, X-ray diffraction, and synchronous thermal analysis. It is claimed that it represents an interpolymeric complex of polyvinyl alcohol and hydrated titanium oxide.

Synthesis, structure, electrochemistry, and photophysics of methyl-substituted phenylpyridine ortho-metalated iridium(III) complexes

International Nuclear Information System (INIS)

Garces, F.O.; King, K.A.; Watts, R.J.

1988-01-01

Synthetic, structural, photophysical, and electrochemical characterizations of ortho-metalated [Ir(NC) 2 Cl] 2 dimeric and [Ir(NC) 2 NN]Cl monomeric complexes, where NC = 2(p-tolyl)pyridine (ptpy) or 3-methyl-2-phenylpyridine (mppy) and NN = 2,2'-bipyridine (bpy) are described. Structural characterizations by 1 H and 13 C nuclear magnetic resonance (NMR) indicate the presence of symmetry elements in these complexes. The ultraviolet-visible absorption properties of these complexes are reported. The results of voltametric measurements of these complexes are included. 55 references, 10 figures, 6 tables

New bases for the evaluation of interaction energies: An ab initio study of the CO-Ne van der Waals complex intermolecular potential and ro-vibrational spectrum

International Nuclear Information System (INIS)

Bouzon Capelo, Silvia; Baranowska-Laczkowska, Angelika; Fernandez, Berta

2011-01-01

Graphical abstract: CO-Ne IPES. Highlights: → From the LPol, MLPol, and aug-pc-2 bases we obtained new bases for the evaluation of CO-Ne interaction energies. → We checked the bases on the evaluation of the rovibrational spectrum. → The results were satisfactory, being the new bases more efficient than those previously available. - Abstract: Recently we have derived new efficient basis sets for the evaluation of interaction energies in the X-Y (X, Y = He, Ne, Ar) van der Waals complexes. Here we extend the study to the CO-Ne complex. For this, we start with a systematic basis set study, where the LPol, MLPol and Jensen's aug-pc-2 basis sets are considered as starting point (for the Ne atom LPol bases are developed). As reference we take interaction energy results obtained with Dunning's augmented correlation consistent polarized valence basis sets. In all cases we test extensions with different sets of midbond functions. With the selected bases we evaluate CCSD(T) interaction potentials, and to check the potentials further, we obtain the ro-vibrational spectrum of the complex. The results are compared to the available experimental data.

Activity uniformity of Ir-192 seeds

International Nuclear Information System (INIS)

Ling, C.C.; Gromadzki, Z.C.

1981-01-01

A simple device that uses materials and apparatus commonly available in a radiotherapy department has been designed, fabricated and used in routine quality control relative to the activity uniformity of clinical Ir-192 seeds in ribbons. Detailed evaluation indicated that this system is easy to use and can yield relative activity measurements of individual Ir-192 seeds accurate to within 2%. With this device, activity uniformity of commercial Ir-192 seeds from two manufacturers has been assessed. For the seven shipments of Ir-192 seeds studied, the root mean square variations of individual seed strength from the average of each shipment ranged from 3.4 to 7.1%. Variation in seed activity by more than +- 10% from the average is not uncommon

Conversion of broadband IR radiation and structural disorder in lithium niobate single crystals with low photorefractive effect

Science.gov (United States)

Litvinova, Man Nen; Syuy, Alexander V.; Krishtop, Victor V.; Pogodina, Veronika A.; Ponomarchuk, Yulia V.; Sidorov, Nikolay V.; Gabain, Aleksei A.; Palatnikov, Mikhail N.; Litvinov, Vladimir A.

2016-11-01

The conversion of broadband IR radiation when the noncritical phase matching condition is fulfilled in lithium niobate (LiNbO3) single crystals with stoichiometric (R = Li/Nb = 1) and congruent (R = 0.946) compositions, as well as in congruent single crystals doped with zinc has been investigated. It is shown that the spectrum parameters of converted radiation, such as the conversion efficiency, spectral width and position of maximum, depend on the ordering degree of structural units of the cation sublattice along the polar axis of crystal.

Enhancing work outcomes of employees with autism spectrum disorder through leadership: leadership for employees with autism spectrum disorder.

Science.gov (United States)

Parr, Alissa D; Hunter, Samuel T

2014-07-01

The focus of this study was to identify leader behaviors that elicit successful engagement of employees with autism spectrum disorder, a population that is powerfully emerging into the workplace. The ultimate goal was to improve the quality of life of employees with autism spectrum disorder by facilitating an environment leading to their success. Through a series of interviews with 54 employees with autism spectrum disorder, results indicated that leadership has a great effect on employee attitudes and performance, and that the notion of leadership preferences is quite complex culminating in several important behaviors rather than one superior leadership theory. Implications and future research directions are discussed. © The Author(s) 2013.

Second Workshop on Supporting Complex Search Tasks

NARCIS (Netherlands)

Belkin, Nicholas J.; Bogers, Toine; Kamps, Jaap; Kelly, Diane; Koolen, Marijn; Yilmaz, Emine

2017-01-01

There is broad consensus in the field of IR that search is complex in many use cases and applications, both on the Web and in domain specific collections, and both professionally and in our daily life. Yet our understanding of complex search tasks, in comparison to simple look up tasks, is

WW Domain Folding Complexity Revealed by Infrared Spectroscopy

OpenAIRE

Davis, Caitlin M.; Dyer, R. Brian

2014-01-01

Although the intrinsic tryptophan fluorescence of proteins offers a convenient probe of protein folding, interpretation of the fluorescence spectrum is often difficult because it is sensitive to both global and local changes. Infrared (IR) spectroscopy offers a complementary measure of structural changes involved in protein folding, because it probes changes in the secondary structure of the protein backbone. Here we demonstrate the advantages of using multiple probes, infrared and fluorescen...

UNTANGLING THE NEAR-IR SPECTRAL FEATURES IN THE PROTOPLANETARY ENVIRONMENT OF KH 15D

Energy Technology Data Exchange (ETDEWEB)

Arulanantham, Nicole A.; Herbst, William; Gilmore, Martha S.; Cauley, P. Wilson [Astronomy Department, Wesleyan University, Middletown, CT 06459 (United States); Leggett, S. K., E-mail: nicole.arulanantham@colorado.edu [Gemini Observatory (North), Hilo, HI 96720 (United States)

2017-01-10

We report on Gemini/GNIRS observations of the binary T Tauri system V582 Mon (KH 15D) at three orbital phases. These spectra allow us to untangle five components of the system: the photosphere and magnetosphere of star B, the jet, scattering properties of the ring material, and excess near-infrared (near-IR) radiation previously attributed to a possible self-luminous planet. We confirm an early-K subgiant classification for star B and show that the magnetospheric He i emission line is variable, possibly indicating increased mass accretion at certain times. As expected, the H{sub 2} emission features associated with the inner part of the jet show no variation with orbital phase. We show that the reflectance spectrum for the scattered light has a distinctive blue slope and spectral features consistent with scattering and absorption by a mixture of water and methane ice grains in the 1–50 μ m size range. This suggests that the methane frost line is closer than ∼5 au in this system, requiring that the grains be shielded from direct radiation. After correcting for features from the scattered light, jet, magnetosphere, and photosphere, we confirm the presence of leftover near-IR light from an additional source, detectable near minimum brightness. A spectral emission feature matching the model spectrum of a 10 M {sub J}, 1 Myr old planet is found in the excess flux, but other expected features from this model are not seen. Our observations, therefore, tentatively support the picture that a luminous planet is present within the system, although they cannot yet be considered definitive.

Diiridium Bimetallic Complexes Function as a Redox Switch To Directly Split Carbonate into Carbon Monoxide and Oxygen.

Science.gov (United States)

Chen, Tsun-Ren; Wu, Fang-Siou; Lee, Hsiu-Pen; Chen, Kelvin H-C

2016-03-23

A pair of diiridium bimetallic complexes exhibit a special type of oxidation-reduction reaction that could directly split carbonate into carbon monoxide and molecular oxygen via a low-energy pathway needing no sacrificial reagent. One of the bimetallic complexes, Ir(III)(μ-Cl)2Ir(III), can catch carbonato group from carbonate and reduce it to CO. The second complex, the rare bimetallic complex Ir(IV)(μ-oxo)2Ir(IV), can react with chlorine to release O2 by the oxidation of oxygen ions with synergistic oxidative effect of iridium ions and chlorine atoms. The activation energy needed for the key reaction is quite low (∼20 kJ/mol), which is far less than the dissociation energy of the C═O bond in CO2 (∼750 kJ/mol). These diiridium bimetallic complexes could be applied as a redox switch to split carbonate or combined with well-known processes in the chemical industry to build up a catalytic system to directly split CO2 into CO and O2.

Thermal-to-visible transducer (TVT) for thermal-IR imaging

Science.gov (United States)

Flusberg, Allen; Swartz, Stephen; Huff, Michael; Gross, Steven

2008-04-01

We have been developing a novel thermal-to-visible transducer (TVT), an uncooled thermal-IR imager that is based on a Fabry-Perot Interferometer (FPI). The FPI-based IR imager can convert a thermal-IR image to a video electronic image. IR radiation that is emitted by an object in the scene is imaged onto an IR-absorbing material that is located within an FPI. Temperature variations generated by the spatial variations in the IR image intensity cause variations in optical thickness, modulating the reflectivity seen by a probe laser beam. The reflected probe is imaged onto a visible array, producing a visible image of the IR scene. This technology can provide low-cost IR cameras with excellent sensitivity, low power consumption, and the potential for self-registered fusion of thermal-IR and visible images. We will describe characteristics of requisite pixelated arrays that we have fabricated.

History of the study of the telluric spectrum of the sun. II - 1900-1970

Energy Technology Data Exchange (ETDEWEB)

Melnikov, O.A.; Khilov, E.D.

1981-01-01

Studies of the telluric bands and lines in the solar spectrum are reviewed which were carried out between 1900 to 1970. Telluric features observed in the IR, visible, and UV regions are examined in detail. Special attention is given to telluric absorption bands due to H2O, O2, O3, CH4, N2O, CO2, C2H4, (O2)2, and HDO.

Inclusion Mechanism and Heat Stability of the Complex of 4 ...

African Journals Online (AJOL)

The physicochemical properties of the complex were evaluated by Fourier transform infrared spectroscopy (FT-IR) and x-ray diffractometry (XRD) while the heat stability of the complex was measured by thermogravimetric/differential scanning calorimetry (TG/DSC). Results: The stability constants of the complexes were ...

Embracing Complexity: Using Technology to Develop a Life-Long Learning Model for Non-Working Time in the Interdependent Homes for Adults with Autism Spectrum Disorders

Science.gov (United States)

Chiang, I-Tsun; Chen, Mei-Li

2011-01-01

The purpose of this study was to employ complexity theory as a theoretical framework and technology to facilitate the development of a life-long learning model for non-working time in the interdependent homes for adults with Autism Spectrum Disorders (ASD). A "Shining Star Sustainable Action Project" of the ROC Foundation for Autistic…

Kinetics and evolved gas analysis for pyrolysis of food processing wastes using TGA/MS/FT-IR.

Science.gov (United States)

Özsin, Gamzenur; Pütün, Ayşe Eren

2017-06-01

The objective of this study was to identify the pyrolysis of different bio-waste produced by food processing industry in a comprehensible manner. For this purpose, pyrolysis behaviors of chestnut shells (CNS), cherry stones (CS) and grape seeds (GS) were investigated by thermogravimetric analysis (TGA) combined with a Fourier-transform infrared (FT-IR) spectrometer and a mass spectrometer (MS). In order to make available theoretical groundwork for biomass pyrolysis, activation energies were calculated with the help of four different model-free kinetic methods. The results are attributed to the complex reaction schemes which imply parallel, competitive and complex reactions during pyrolysis. During pyrolysis, the evolution of volatiles was also characterized by FT-IR and MS. The main evolved gases were determined as H 2 O, CO 2 and hydrocarbons such as CH 4 and temperature dependent profiles of the species were obtained. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reactivity of the parent amido complexes of iridium with olefins: C-NH2 bond formation versus C-H activation.

Science.gov (United States)

Mena, Inmaculada; García-Orduña, Pilar; Polo, Víctor; Lahoz, Fernando J; Casado, Miguel A; Oro, Luis A

2017-08-29

Herein we report on the different chemical reactivity displayed by two mononuclear terminal amido compounds depending on the nature of the coordinated diene. Hence, treatment of amido-bridged iridium complexes [{Ir(μ-NH 2 )(tfbb)} 3 ] (1; tfbb = tetrafluorobenzobarrelene) with dppp (dppp = bis(diphenylphosphane)propane) leads to the rupture of the amido bridges forming the mononuclear terminal amido compound [Ir(NH 2 )(dppp)(tfbb)] (3) in the first stage. On changing the reaction conditions, the formation of a C-NH 2 bond between the amido moiety and the coordinated diene is observed and a new dinuclear complex [{Ir(1,2-η 2 -4-κ-C 12 H 8 F 4 N)(dppp)} 2 (μ-dppp)] (4) has been isolated. On the contrary, the diiridium amido-bridged complex [{Ir(μ-NH 2 )(cod)} 2 ] (2; cod = 1,5-cyclooctadiene) in the presence of dppb (dppb = bis(diphenylphosphane)butane) allows the isolation of a mononuclear complex [Ir(1,2,3-η 3 -6-κ-C 8 H 10 )H(dppb)] (5), as a consequence of the extrusion of ammonia. The monitoring of the reaction of 2 with dppb (and dppp) allowed us to detect terminal amido complexes [Ir(NH 2 )(P-P)(cod)] (P-P = dppb (6), dppp (7)) in solution, as confirmed by an X-ray analysis of 7. Complex 7 was observed to evolve into hydrido species 5 at room temperature. DFT studies showed that C-H bond activation occurs through the deprotonation of one methylene fragment of the cod ligand by the highly basic terminal amido moiety instead of C-H oxidative addition to the Ir(i) center.

Isolated Gramicidin Peptides Probed by IR Spectroscopy

NARCIS (Netherlands)

Rijs, A. M.; Kabelac, M.; Abo-Riziq, A.; Hobza, P.; de Vries, M. S.

2011-01-01

We report double-resonant IR/UV ion-dip spectroscopy of neutral gramicidin peptides in the gas phase. The IR spectra of gramicidin A and C, recorded in both the 1000 cm(-1) to 1800 cm(-1) and the 2700 to 3750 cm(-1) region, allow structural analysis. By studying this broad IR range, various local

Braškių 'Senga Sengana' prisitaikymas prie diferencijuoto ir kompleksinio UV-B spinduliuotės ir ozono poveikio

OpenAIRE

Brazaitytė, Aušra; Sakalauskaitė, Jurga; Duchovskis, Pavelas; Šikšnianienė, Jūratė Bronė; Samuolienė, Giedrė; Ulinskaitė, Raimonda; Baranauskis, Kęstutis; Urbonavičiūtė, Akvilė; Šabajevienė, Gintarė; Gelvonauskis, Bronislovas; Uselis, Nobertas; Vagusevičienė, Ilona

2007-01-01

2005 m. Lietuvos sodininkystės ir daržininkystės instituto fitotrono komplekse nustatytas diferencijuotas ir kompleksinis UV-B spinduliuotės bei ozono poveikis braškių augimui ir fotosintezės pigmentų pokyčiams bei jų prisitaikymo prie šių stresorių galimybės. Poveikis stresą sukeliančiais veiksniais buvo skirstomas į du laikotarpius: adaptacijos ir pagrindinį. Ozono koncentracija adaptacijos laikotarpiu buvo 80 µg m-3, o pagrindinio poveikio – 240 µg m-3. Tokia koncentracija buvo palaikoma 7...

Experimental and theoretical studies on IR, Raman, and UV-Vis spectra of quinoline-7-carboxaldehyde.

Science.gov (United States)

Kumru, M; Küçük, V; Kocademir, M; Alfanda, H M; Altun, A; Sarı, L

2015-01-05

Spectroscopic properties of quinoline-7-carboxaldehyde (Q7C) have been studied in detail both experimentally and theoretically. The FT-IR (4000-50 cm(-1)), FT-Raman (4000-50 cm(-1)), dispersive-Raman (3500-50 cm(-1)), and UV-Vis (200-400 nm) spectra of Q7C were recorded at room temperature (25 °C). Geometry parameters, potential energy surface about CCH(O) bond, harmonic vibrational frequencies, IR and Raman intensities, UV-Vis spectrum, and thermodynamic characteristics (at 298.15K) of Q7C were computed at Hartree-Fock (HF) and density functional B3LYP levels employing the 6-311++G(d,p) basis set. Frontier molecular orbitals, molecular electrostatic potential, and Mulliken charge analyses of Q7C have also been performed. Q7C has two stable conformers that are energetically very close to each other with slight preference to the conformer that has oxygen atom of the aldehyde away from the nitrogen atom of the quinoline. Copyright © 2014 Elsevier B.V. All rights reserved.

The influence of different cyclometalated ligand substituents and ancillary ligand on the phosphorescent properties of iridium(III) complexes

Energy Technology Data Exchange (ETDEWEB)

Zhang, Qing; Li, Yuanyuan; Wang, Xin; Wang, Li, E-mail: chemwangl@henu.edu.cn; Zhang, Jinglai, E-mail: zhangjinglai@henu.edu.cn

2016-07-01

Four iridium(III) complexes, (dfpmpy){sub 2}Ir(pic), (1), (dfpmpy){sub 2}Ir(EO{sub 2}-pic) (2), (dfpmpy){sub 2}Ir(pic-N-O) (3), and (dfpmpy){sub 2}Ir(EO{sub 2}-pic-N-O) (4) (dfpmpy = 2-(2,4-difluorophenyl)-4-methylpyridine, pic = picolinic acid, EO{sub 2}-pic = 4-(2-ethoxyethoxy) picolinic acid, pic-N-O = picolinic acid N-oxide, and EO{sub 2}-pic-N-O = 4-(2-ethoxyethoxy) picolinic acid N-oxide) are investigated by means of the density functional theory/time-dependent density functional theory (DFT/TD-DFT) to explore the influence of the ancillary ligand on the electronic structures, phosphorescent properties, and organic light-emitting diode (OLED) performance. Employing pic-N-O and EO{sub 2}-pic-N-O as the ancillary ligands would decrease the vertical energy and result in the red-shifted wavelength. Then, other four iridium(III) complexes (2a-2d) (See Scheme 1) are designed by introduction of the phenyl and −CHO substituents on the pyridine ring and phenyl ring of complex 2, respectively. As compared with complex 2, theoretical results show that newly designed complexes 2a-2c might be potential candidates for blue-emitting phosphors with better/comparable quantum yield and Δλ. Moreover, the performance of complexes 2a and 2c, i.e., introducing phenyl on the para-position of pyridine ring and phenyl ring in dfpmpy ligand, are better than that of 2b. - Highlights: • The structure-property relationship of Ir(III) complexes are investigated. • The effect of different substituents/positions on properties is explored. • Do the emissions follow the Kasha or non-Kasha scenario? • Newly possible blue-emitting Ir(III) complexes are theoretically designed.

Vartotojų lojalumas : formavimas ir valdymas

OpenAIRE

Zikienė, Kristina

2010-01-01

Vienas iš esminių daugelio organizacijų tikslų, garantuojančių tolesnį sėkmingą konkuravimą nuolat besikeičiančiame verslo pasaulyje, yra vartotojų lojalumo įgijimas ir išlaikymas. Įvairios lojalumo formavimo ir valdymo problemos plačiai ir detaliai analizuojamos šioje mokomojoje knygoje. Knyga pradedama vartotojų lojalumo analize marketingo mokslo raidos kontekste. Tolesnis dėmesys skiriamas vartotojų lojalumo vadybinio aspekto analizei, atskleidžiant vartotojų lojalumo koncepcijos teorines ...

Broilerienos paklausa ir pasiūla Lietuvoje

OpenAIRE

Paškauskienė, Kristina

2008-01-01

Labai svarbu ir savalaikiškai ištirti vartotojų poreikį broilerienai, aktualu nustatyti vartotojų požiūrį į Lietuvoje užauginamą produkciją bei importuotą. ir kokia yra priklausomybė vyrų bei moterų tarpe, ir nuo gaunamo atlyginimo. Vartotojų tyrimai rodo, kad auga paklausa lengvai virškinamiems, greitai paruošiamiems, aukštos maistinės kokybės gyvulininkystės produktams. Darbo tikslas - Išsiaiškinti broilerienos paklausą ir pasiūlą Lietuvoje, įvertinti broilerienos suvartojimo tendencija...

Intersystem-crossing and phosphorescence rates in fac-Ir{sup III}(ppy){sub 3}: A theoretical study involving multi-reference configuration interaction wavefunctions

Energy Technology Data Exchange (ETDEWEB)

Kleinschmidt, Martin; Marian, Christel M., E-mail: Christel.Marian@hhu.de [Institute of Theoretical and Computational Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf (Germany); Wüllen, Christoph van [Fachbereich Chemie and Forschungszentrum OPTIMAS, Technical University of Kaiserslautern, Erwin-Schrödinger-Straße 52, 67663 Kaiserslautern (Germany)

2015-03-07

We have employed combined density functional theory and multi-reference configuration interaction methods including spin–orbit coupling (SOC) effects to investigate the photophysics of the green phosphorescent emitter fac-tris-(2-phenylpyridine)iridium (fac-Ir(ppy){sub 3}). A critical evaluation of our quantum chemical approaches shows that a perturbational treatment of SOC is the method of choice for computing the UV/Vis spectrum of this heavy transition metal complex while multi-reference spin–orbit configuration interaction is preferable for calculating the phosphorescence rates. The particular choice of the spin–orbit interaction operator is found to be of minor importance. Intersystem crossing (ISC) rates have been determined by Fourier transformation of the time correlation function of the transition including Dushinsky rotations. In the electronic ground state, fac-Ir(ppy){sub 3} is C{sub 3} symmetric. The calculated UV/Vis spectrum is in excellent agreement with experiment. The effect of SOC is particularly pronounced for the metal-to-ligand charge transfer (MLCT) band in the visible region of the absorption spectrum which does not only extend its spectral onset towards longer wavelengths but also experiences a blue shift of its maximum. Pseudo-Jahn-Teller interaction leads to asymmetric coordinate displacements in the lowest MLCT states. Substantial electronic SOC and a small energy gap make ISC an ultrafast process in fac-Ir(ppy){sub 3}. For the S{sub 1}↝T{sub 1} non-radiative transition, we compute a rate constant of k{sub ISC} = 6.9 × 10{sup 12} s{sup −1} which exceeds the rate constant of radiative decay to the electronic ground state by more than six orders of magnitude, in agreement with the experimental observation of a subpicosecond ISC process and a triplet quantum yield close to unity. As a consequence of the geometric distortion in the T{sub 1} state, the T{sub 1} → S{sub 0} transition densities are localized on one of the

Microdosimetric evaluation of relative biological effectiveness for 103PD, 125I, 241AM, and 192IR brachytherapy sources

International Nuclear Information System (INIS)

Wuu, C.S.; Kliauga, P.; Zaider, M.; Amols, H.I.

1996-01-01

Purpose: To determine the microdosimetric-derived relative biological effectiveness (RBE) of 103 Pd, 125 I, 241 Am, and 192 Ir brachytherapy sources at low doses and/or low dose rates. Methods and Materials: The Theory of Dual Radiation Action can be used to predict expected RBE values based on the spatial distribution of energy deposition at microscopic levels from these sources. Single-event lineal energy spectra for these isotopes have been obtained both experimentally and theoretically. A grid-defined wall-less proportional counter was used to measure the lineal energy distributions. Unlike conventional Rossi proportional counters, the counter used in these measurements has a conducting nylon fiber as the central collecting anode and has no metal parts. Thus, the Z-dependence of the photoelectric effect is eliminated as a source of measurement error. Single-event spectra for these brachytherapy sources have been also calculated by: (a) the Monte Carlo code MCNP to generate the electron slowing down spectrum, (b) transport of monoenergetic electron tracks, event by event, with our Monte Carlo code DELTA, (c) using the concept of associated volume to obtain the lineal energy distribution f(y) for each monoenergetic electron, and (d) obtaining the composite lineal energy spectrum for a given brachytherapy source based on the electron spectrum calculated at step (a). Results: Relative to 60 Co, the RBE values obtained from this study are: 2.3 for 103 Pd, 2.1 for 125 I, 2.1 for 241 Am, and 1.3 for 192 Ir. Conclusions: These values are consistent with available data from in vitro cell survival experiments. We suggest that, at least for these brachytherapy sources, microdosimetry may be used as a credible alternative to time-consuming (and often uncertain) radiobiological experiments to obtain information on radition quality and make reliable predictions of RBE in low dose rate brachytherapy

Determination of the absolute K through O conversion coefficients of the 80-keV M4 transition in /sup 193/Ir/sup m/

International Nuclear Information System (INIS)

Lindner, M.; Gunnink, R.; Nagle, R.J.

1987-01-01

We produced carrier-free, nearly isotopically pure /sup 193/Ir/sup m/ from thermal-neutron irradiation of /sup 192/Os. From studies of the conversion-electron spectrum, the photon spectrum, and the absolute counting rates, we determined the absolute K, L1, L2, L3, M1, M3, M5, N, and O+P conversion coefficients for the first time. With possibly one exception, these values agree closely with theoretical calculations. The value for the energy of the unconverted gamma ray was found to be 80.22 +- 0.02 keV. The half-life for /sup 193/Ir/sup m/ determined by absolute electron counting in a proportional counter of 100% counting efficiency (4πβ) was found to be 10.53 +- 0.04 d. We have determined the L 1 subshell fluorescence yield, ω 1 , to be 0.120 +- 0.003 for iridium. Based upon our measurements of initial and final L subshell vacancies together with a best-fit literature value for ω 2 , we have found a plausible value for the Coster-Kronig coefficient f/sub 12/ to be 0.091 +- 0.011

Single-crystal films of a combination of materials (co-crystal) involving DAST and IR-125 for electro-optic applications

Science.gov (United States)

Narayanan, A.; Titus, J.; Rajagopalan, H.; Vippa, P.; Thakur, M.

2006-03-01

Single-crystal film of DAST (4'-dimethylamino-N-methyl-4-stilbazolium tosylate) has been shown [1] to have exceptionally large electro-optic coefficients (r11 ˜ 770 pm/V at 633 nm). In this report, single crystal film of a combination of materials (co-crystal) involving DAST and a dye molecule IR-125 will be discussed. Modified shear method was used to prepare the co-crystal films. The film has been characterized using polarized optical microscopy, optical absorption spectroscopy and x-ray diffraction. The optical absorption spectrum has two major bands: one at about 350--600 nm corresponding to DAST and the other at about 600-900 nm corresponding to IR-125. The x-ray diffraction results show peaks involving the presence of DAST and IR-125 within the co-crystal film. Since the co-crystal has strong absorption at longer wavelengths it is expected to show higher electro-optic coefficients at longer wavelengths. Preliminary measurements at 1.55 μm indicate a high electro-optic coefficient of the co-crystal film. [1] Swamy, Kutty, Titus, Khatavkar, Thakur, Appl. Phys. Lett. 2004, 85, 4025; Kutty, Thakur, Appl. Phys. Lett. 2005, 87, 191111.

Uranyl tris-beta-diketonate complexes

International Nuclear Information System (INIS)

Sidorenko, G.V.; Adamov, V.M.; Shcherbakova, L.L.; Suglubov, D.N.

1986-01-01

Uranyl tris-pivaloyltrifluoroacetonates (M/IOTA/UO 2 L 3 ; M/IOTA/ = Na, K, Cs, 1/2Ba, NR 4 ; R = C 8 H 17 ) and tris-dipivaloylmethanate (M/IOTA/UO 2 L/IOTA/ 3 , M/IOTA/ = K) have been synthesized for the first time. The compounds were characterized by chemical analysis and IR, NMR, and mass spectra. NaUO 2 L 3 , KUO 2 L 3 , CsUO 2 L 3 and Ba(UO 2 ) 2 L 6 sublime in high vacuum with partial decomposition. Specifically, decomposition gives UL 4 , identified by mass spectrometry. All the tris-complexes except those with outer-sphere NR 4 cation are characterized by an asymmetric structure of the uranyl group, recorded by IR spectroscopy using isotopic substitution of 18 O in uranyl. NMR spectra of the tris-complexes indicate the equivalence of all beta-diketonate groups, i.e., a coordination number of six for uranyl

Studies on polymer electrolyte poly(vinyl) pyrrolidone (PVP) complexed with ionic liquid: Effect of complexation on thermal stability, conductivity and relaxation behaviour

Energy Technology Data Exchange (ETDEWEB)

Saroj, A.L. [Department of Physics, Banaras Hindu University, Varanasi, 221005 (India); Singh, R.K., E-mail: rksingh_17@rediffmail.com [Department of Physics, Banaras Hindu University, Varanasi, 221005 (India); Chandra, S. [Department of Physics, Banaras Hindu University, Varanasi, 221005 (India)

2013-03-01

Highlights: Black-Right-Pointing-Pointer PVP + IL based polymer electrolyte films have been prepared and studied. Black-Right-Pointing-Pointer The complexation/interaction of PVP with IL has been confirmed by FT-IR analysis. Black-Right-Pointing-Pointer The conductivity and relaxation frequency increases with increasing IL content. Black-Right-Pointing-Pointer Two relaxation peaks for complexed and uncomplexed PVP with IL have been observed. - Abstract: Polymer electrolyte films of PVP + x wt% ionic liquid (IL) (1-ethyl-3-methylimidazolium tetrafluoroborate [EMIM][BF{sub 4}]) for x = 0, 5, 10, 15, 20, 25 wt% have been prepared using solution cast technique. These films were characterized by TGA, DSC, FT-IR and ac impedance spectroscopy techniques. From XRD studies it is found that the inclusion of IL increases the amorphocity of polymeric membranes. DSC thermograms show that the glass transition (T{sub g}) and melting temperatures (T{sub m}) of PVP shift upon complexation with IL. FT-IR analysis shows the complexation of PVP with IL. Thermogravimetric studies show that PVP decomposes in a single step while PVP/IL membranes exhibit two step decomposition; lower value of decomposition temperature corresponds to the decomposition of PVP/IL complex while the higher decomposition temperature has been attributed to the decomposition of PVP. The decomposition temperature of PVP/IL complex decreases with the increasing amount of IL in the PVP membrane. Temperature dependence of conductivity and dielectric relaxation frequencies have also been studied for PVP and PVP/IL membranes. Both show thermally activated Arrhenius behaviour.

Uranyl complexes of glutathione

Energy Technology Data Exchange (ETDEWEB)

Marzotto, A [Consiglio Nazionale delle Ricerche, Padua (Italy). Lab. di Chimica e Tecnologia dei Radioelementi

1977-01-01

Dioxouranium(VI) complexes of the tripeptide glutathione having different molar ratios were prepared and studied by IR, PMR, electronic absorption and circular dichroism spectra. The results indicate that coordination occurs at the carboxylato groups, acting as monodentate ligands, whereas no significant interaction with the amino and sulfhydrylic groups takes place.

Using IR spectroscopy and multivariate curve resolution to elucidate mechanism of heat-induced decomposition of an organic complex

DEFF Research Database (Denmark)

Karpushkin, Evgeny; Gvozdik, Nataliya; Kucheryavskiy, Sergey V.

the opportunity to carry out simultaneous thermogravimetry/differential scanning calorimetry analysis and IR/Raman/mass spectrometry investigation of the evolving gaseous products. However, elucidation of the mechanism of the reactions occurring upon heat- ing is not completely straightforward, due to a number...

Molecular complexes of tungsten oxotetrachloride with azomethins

International Nuclear Information System (INIS)

Abramenko, Yu.V.; Garnovskij, A.D.; Abramenko, V.A.; Medvedeva, T.E.

1992-01-01

Series of new molecular complexes of tungsten oxotetrachloride with benza- and salicylalimines of equimolar compositions obtained. Substances are studied using element analysis, IR spectroscopy and conductometry. Octahedral structure of complexes with central atom coordination of benzalaniline molecules via azomethin nitrogen atom, and salicylalimines - via carbonyl oxygen atom of quinoid tantometric form of ligand is assumed

Quasinormal modes of a strongly coupled nonconformal plasma and approach to criticality

Science.gov (United States)

Betzios, Panagiotis; Gürsoy, Umut; Järvinen, Matti; Policastro, Giuseppe

2018-04-01

We study fluctuations around equilibrium in a class of strongly interacting nonconformal plasmas using holographic techniques. In particular, we calculate the quasinormal mode spectrum of black hole backgrounds that approach Chamblin-Reall plasmas in the IR. In a specific limit, related to the exact linear-dilaton background in string theory, we observe that the plasma approaches criticality and we obtain the quasinormal spectrum analytically. We regulate the critical limit by gluing the IR geometry that corresponds to the nonconformal plasma to a part of AdS space-time in the UV. Near criticality, the spectrum can still be computed analytically and we find two sets of quasinormal modes, related to the IR and UV parts of the geometry. In the critical limit, the quasinormal modes accumulate to form a branch cut in the correlators of the energy-momentum tensor on the real axis of the complex frequency plane.

Role of IRS-2 in insulin and cytokine signalling.

Science.gov (United States)

Sun, X J; Wang, L M; Zhang, Y; Yenush, L; Myers, M G; Glasheen, E; Lane, W S; Pierce, J H; White, M F

1995-09-14

The protein IRS-1 acts as an interface between signalling proteins with Src-homology-2 domains (SH2 proteins) and the receptors for insulin, IGF-1, growth hormone, several interleukins (IL-4, IL-9, IL-13) and other cytokines. It regulates gene expression and stimulates mitogenesis, and appears to mediate insulin/IGF-1-stimulated glucose transport. Thus, survival of the IRS-1-/- mouse with only mild resistance to insulin was surprising. This dilemma is provisionally resolved with our discovery of a second IRS-signalling protein. We purified and cloned a likely candidate called 4PS from myeloid progenitor cells and, because of its resemblance to IRS-1, we designate it IRS-2. Alignment of the sequences of IRS-2 and IRS-1 revealed a highly conserved amino terminus containing a pleckstrin-homology domain and a phosphotyrosine-binding domain, and a poorly conserved carboxy terminus containing several tyrosine phosphorylation motifs. IRS-2 is expressed in many cells, including tissues from IRS-1-/- mice, and may be essential for signalling by several receptor systems.

IR thermocycler for centrifugal microfluidic platform with direct on-disk wireless temperature measurement system

Science.gov (United States)

Burger, J.; Gross, A.; Mark, D.; Roth, G.; von Stetten, F.; Zengerle, R.

2011-06-01

The direct on-disk wireless temperature measurement system [1,2] presented at μTAS 2010 was further improved in its robustness. We apply it to an IR thermocycler as part of a centrifugal microfluidic analyzer for polymerase chain reactions (PCR). This IR thermocycler allows the very efficient direct heating of aqueous liquids in microfluidic cavities by an IR radiation source. The efficiency factor of this IR heating system depends on several parameters. First there is the efficiency of the IR radiator considering the transformation of electrical energy into radiation energy. This radiation energy needs to be focused by a reflector to the center of the cavity. Both, the reflectors shape and the quality of the reflecting layer affect the efficiency. On the way to the center of the cavity the radiation energy will be diminished by absorption in the surrounding air/humidity and especially in the cavity lid of the microfluidic disk. The transmission spectrum of the lid material and its thickness is of significant impact. We chose a COC polymer film with a thickness of 150 μm. At a peak frequency of the IR radiator of ~2 μm approximately 85 % of the incoming radiation energy passes the lid and is absorbed within the first 1.5 mm depth of liquid in the cavity. As we perform the thermocycling for a PCR, after heating to the denaturation temperature of ~ 92 °C we need to cool down rapidly to the primer annealing temperature of ~ 55 °C. Cooling is realized by 3 ventilators venting air of room temperature into the disk chamber. Due to the air flow itself and an additional rotation of the centrifugal microfluidic disk the PCR reagents in the cavities are cooled by forced air convection. Simulation studies based upon analogous electrical models enable to optimize the disk geometry and the optical path. Both the IR heater and the ventilators are controlled by the digital PID controller HAPRO 0135 [3]. The sampling frequency is set to 2 Hz. It could be further increased up

NaIrO3-A pentavalent post-perovskite

International Nuclear Information System (INIS)

Bremholm, M.; Dutton, S.E.; Stephens, P.W.; Cava, R.J.

2011-01-01

Sodium iridium (V) oxide, NaIrO 3, was synthesized by a high pressure solid state method and recovered to ambient conditions. It is found to be isostructural with CaIrO 3 , the much-studied structural analog of the high-pressure post-perovskite phase of MgSiO 3 . Among the oxide post-perovskites, NaIrO 3 is the first example with a pentavalent cation. The structure consists of layers of corner- and edge-sharing IrO 6 octahedra separated by layers of NaO 8 bicapped trigonal prisms. NaIrO 3 shows no magnetic ordering and resistivity measurements show non-metallic behavior. The crystal structure, electrical and magnetic properties are discussed and compared to known post-perovskites and pentavalent perovskite metal oxides. -- Graphical abstract: Sodium iridium(V) oxide, NaIrO 3 , synthesized by a high pressure solid state method and recovered to ambient conditions is found to crystallize as the post-perovskite structure and is the first example of a pentavalent ABO 3 post-perovskite. Research highlights: → NaIrO 3 post-perovskite stabilized by pressure. → First example of a pentavalent oxide post-perovskite. → Non-metallic and non-magnetic behavior of NaIrO 3 .

How to remedy Eurocentrism in IR?

DEFF Research Database (Denmark)

Bilgin, Pinar

2016-01-01

While IR's Eurocentric limits are usually acknowledged, what those limits mean for theorizing about the international is seldom clarified. In The Global Transformation, Buzan and Lawson offer a 'composite approach' that goes some way towards addressing IR's Eurocentrism, challenging existing myth...

Endurance test on IR rig for RI production

International Nuclear Information System (INIS)

Chung, Heung June; Youn, Y. J.; Han, H. S.; Hong, S. B.; Cho, Y. G.; Ryu, J. S.

2000-12-01

This report presents the pressure drop, vibration and endurance test results for IR rig for RI production which were desigened and fabricated by KAERI. From the pressure drop test results, it is noted that the flow rate through the IR rig corresponding to the pressure drop of 200 kPa is measured to be about 3.12 kg/sec. Vibration frequency for the IR rig ranges from 13 to 17 Hz. RMS(Root Mean Square) displacement for the IR rig is less than 30 μm, and the maximum displacement is less than 110μm. These experimental results show that the design criteria of IR rig meet the HANARO limit conditions. Endurance test results show that the appreciable fretting wear for the IR rig does not occur, however tiny trace of wear between contact points is observed

Use of HOMA-IR in hepatitis C.

Science.gov (United States)

Eslam, M; Kawaguchi, T; Del Campo, J A; Sata, M; Khattab, M Abo-Elneen; Romero-Gomez, M

2011-10-01

Chronic infection with hepatitis C virus (HCV) can induce insulin resistance (IR) in a genotype-dependent manner and contributes to steatosis, progression of fibrosis and resistance to interferon plus ribavirin therapy. Our understanding of HCV-induced IR has improved considerably over the years, but certain aspects concerning its evaluation still remain elusive to clinical researchers. One of the most important issues is elucidating the ideal method for assessment of IR in the setting of hepatitis C. The hyperinsulinaemic euglycaemic clamp is the gold standard method for determining insulin sensitivity, but is impractical as it is labour intensive and time-consuming. To date, all human studies except for four where IR was evaluated in the HCV setting, an estimation of IR has been used rather than direct measurements of insulin-mediated glucose uptake. The most commonly used estimation in the HCV population is the homeostasis model assessment of insulin resistance (HOMA-IR) which is calculated from a single measurement of fasting insulin and glucose. In this article, we review the use and reporting of HOMA in the literature and provide guidance on its appropriate as well as inappropriate use in the hepatitis setting. © 2011 Blackwell Publishing Ltd.

Probing the Diffuse Optical-IR Background with TeV Blazars Detected with the MAGIC Telescopes

Energy Technology Data Exchange (ETDEWEB)

Prandini, Elisa [Dipartimento di Fisica e Astronomia “G. Galilei”, University of Padova, Padua (Italy); Domínguez, Alberto [Departamento de Física Atómica, Universidad Complutense, Madrid (Spain); Fallah Ramazani, Vandad [Tuorla observatory, University of Turku, Turku (Finland); Hassan, Tarek [IFAE, The Barcelona Institute of Science and Technology, Bellaterra (Spain); Mazin, Daniel [Max Planck Institute for Physics, Munich (Germany); Institute for Cosmic Ray Research, University of Tokyo, Tokyo (Japan); Moralejo, Abelardo [IFAE, The Barcelona Institute of Science and Technology, Bellaterra (Spain); Nievas Rosillo, Mireia [Departamento de Física Atómica, Universidad Complutense, Madrid (Spain); Vanzo, Gaia; Vazquez Acosta, Monica, E-mail: prandini@pd.infn.it [Instituto de Astrofísica de Canarias, Tenerife (Spain); Departamento de Astrofisica, Universidad de La Laguna, Tenerife (Spain)

2017-11-22

Blazars are radio loud quasars whose jet points toward the observer. The observed emission is mostly non-thermal, dominated by the jet emission, and in some cases extends up to the very high energy gamma rays (VHE; E > 100 GeV). To date, more than 60 blazars have been detected at VHE mainly with ground-based imaging atmospheric Cherenkov telescopes (IACTs) such as MAGIC, H.E.S.S., and VERITAS. Energetic photons from a blazar may interact with the diffuse optical and IR background (the extragalactic background light, EBL) leaving an imprint on the blazar energy spectrum. This effect can be used to constrain the EBL, with basic assumptions on the intrinsic energy spectrum. Current generation of IACTs is providing valuable measurements of the EBL density and energy spectrum from optical to infrared frequencies. In this contribution, we present the latest results obtained with the data taken with the MAGIC telescopes: using 32 spectra from 12 blazars, the scale factor of the optical density predicted by the EBL model from Domínguez et al. (2011) is constrained to be 0.95 (+0.11, −0.12){sub stat} (+0.16, −0.07){sub sys}, where a value of 1 means the perfect match with the model.

Probing the Diffuse Optical-IR Background with TeV Blazars Detected with the MAGIC Telescopes

Directory of Open Access Journals (Sweden)

Elisa Prandini

2017-11-01

Full Text Available Blazars are radio loud quasars whose jet points toward the observer. The observed emission is mostly non-thermal, dominated by the jet emission, and in some cases extends up to the very high energy gamma rays (VHE; E > 100 GeV. To date, more than 60 blazars have been detected at VHE mainly with ground-based imaging atmospheric Cherenkov telescopes (IACTs such as MAGIC, H.E.S.S., and VERITAS. Energetic photons from a blazar may interact with the diffuse optical and IR background (the extragalactic background light, EBL leaving an imprint on the blazar energy spectrum. This effect can be used to constrain the EBL, with basic assumptions on the intrinsic energy spectrum. Current generation of IACTs is providing valuable measurements of the EBL density and energy spectrum from optical to infrared frequencies. In this contribution, we present the latest results obtained with the data taken with the MAGIC telescopes: using 32 spectra from 12 blazars, the scale factor of the optical density predicted by the EBL model from Domínguez et al. (2011 is constrained to be 0.95 (+0.11, −0.12stat (+0.16, −0.07sys, where a value of 1 means the perfect match with the model.

Hermann agreement updates IRS guidelines for incentives.

Science.gov (United States)

Broccolo, B M; Peregrine, M W

1995-01-01

The October 1994 agreement between the Internal Revenue Service (IRS) and Hermann Hospital of Houston, Texas, elucidates current IRS policy on physician recruitment incentives. The IRS distinguishes between the recruiting and the retention of physicians and perimts incentives beyond reasonable compensation in the former but not the latter circumstance. This new agreement, while not legally precedential, nevertheless provides guidance for healthcare organizations seeking safe harbor protection.

Synthesis, structure, redox and spectra of green iridium complexes ...

Indian Academy of Sciences (India)

Reactions of IrCl3 ⋅ H2O with the ligands, 2-[(phenylamino)phenylazo]pyridine (HL1a) and 2-[(-tolylamino)phenylazo]pyridine (HL1b) produce [Ir(L1)2]Cl (L1 = L1a, [1]Cl and L1 = L1b, [2]Cl) along with many unidentified products. The iridium complexes have been characterized by various techniques such as X-ray ...

Drift and transmission FT-IR spectroscopy of forest soils: an approach to determine decomposition processes of forest litter

International Nuclear Information System (INIS)

Haberhauer, G.; Gerzabek, M.H.

1999-06-01

A method is described to characterize organic soil layers using Fourier transformed infrared spectroscopy. The applicability of FT-IR, either dispersive or transmission, to investigate decomposition processes of spruce litter in soil originating from three different forest sites in two climatic regions was studied. Spectral information of transmission and diffuse reflection FT-IR spectra was analyzed and compared. For data evaluation Kubelka Munk (KM) transformation was applied to the DRIFT spectra. Sample preparation for DRIFT is simpler and less time consuming in comparison to transmission FT-IR, which uses KBr pellets. A variety of bands characteristics of molecular structures and functional groups has been identified for these complex samples. Analysis of both transmission FT-IR and DRIFT, showed that the intensity of distinct bands is a measure of the decomposition of forest litter. Interferences due to water adsorption spectra were reduced by DRIFT measurement in comparison to transmission FT-IR spectroscopy. However, data analysis revealed that intensity changes of several bands of DRIFT and transmission FT-IR were significantly correlated with soil horizons. The application of regression models enables identification and differentiation of organic forest soil horizons and allows to determine the decomposition status of soil organic matter in distinct layers. On the basis of the data presented in this study, it may be concluded that FT-IR spectroscopy is a powerful tool for the investigation of decomposition dynamics in forest soils. (author)

Thick-foils activation technique for neutron spectrum unfolding with the MINUIT routine-Comparison with GEANT4 simulations

Science.gov (United States)

Vagena, E.; Theodorou, K.; Stoulos, S.

2018-04-01

Neutron activation technique has been applied using a proposed set of twelve thick metal foils (Au, As, Cd, In, Ir, Er, Mn, Ni, Se, Sm, W, Zn) for off-site measurements to obtain the neutron spectrum over a wide energy range (from thermal up to a few MeV) in intense neutron-gamma mixed fields such as around medical Linacs. The unfolding procedure takes into account the activation rates measured using thirteen (n , γ) and two (n , p) reactions without imposing a guess solution-spectrum. The MINUIT minimization routine unfolds a neutron spectrum that is dominated by fast neutrons (70%) peaking at 0.3 MeV, while the thermal peak corresponds to the 15% of the total neutron fluence equal to the epithermal-resonances area. The comparison of the unfolded neutron spectrum against the simulated one with the GEANT4 Monte-Carlo code shows a reasonable agreement within the measurement uncertainties. Therefore, the proposed set of activation thick-foils could be a useful tool in order to determine low flux neutrons spectrum in intense mixed field.

Detection of metanil yellow contamination in turmeric using FT-Raman and FT-IR spectroscopy

Science.gov (United States)

Dhakal, Sagar; Chao, Kuanglin; Qin, Jianwei; Kim, Moon; Schmidt, Walter; Chan, Dian

2016-05-01

Turmeric is well known for its medicinal value and is often used in Asian cuisine. Economically motivated contamination of turmeric by chemicals such as metanil yellow has been repeatedly reported. Although traditional technologies can detect such contaminants in food, high operational costs and operational complexities have limited their use to the laboratory. This study used Fourier Transform Raman Spectroscopy (FT-Raman) and Fourier Transform - Infrared Spectroscopy (FT-IR) to identify metanil yellow contamination in turmeric powder. Mixtures of metanil yellow in turmeric were prepared at concentrations of 30%, 25%, 20%, 15%, 10%, 5%, 1% and 0.01% (w/w). The FT-Raman and FT-IR spectral signal of pure turmeric powder, pure metanil yellow powder and the 8 sample mixtures were obtained and analyzed independently to identify metanil yellow contamination in turmeric. The results show that FT-Raman spectroscopy and FT-IR spectroscopy can detect metanil yellow mixed with turmeric at concentrations as low as 1% and 5%, respectively, and may be useful for non-destructive detection of adulterated turmeric powder.

Design and Development of transducer for IR radiation measurement

International Nuclear Information System (INIS)

Pattarachindanuwong, Surat; Poopat, Bovornchoke; Meethong, Wachira

2003-06-01

Recently, IR radiation has many important roles such as for plastics industry, food industry and medical instrumentation. The consequence of exposed irradiation objects from IR can be greatly affected by the quantity of IR radiation. Therefore the objectively this research is to design and develop a transducer for IR radiation measurement. By using a quartz halogen lamp as a IR heat source of IR radiation and a thermopile sensor as a transducer. The thermal conductivity of transducer and air flow, were also considered for design and development of transducer. The study shows that the designed transducer can be used and applied in high temperature process, for example, the quality control of welding, the non-contact temperature measurement of drying oven and the testing of IR source in medical therapy device

INCA project for investigation of primary cosmic radiation spectrum

International Nuclear Information System (INIS)

Aleksandrov, K.V.; Erlykin, A.D.; Zhdanov, G.B.

2002-01-01

The scientific purposes of the INCA project and application of the ionization-neutron calorimeter for direct measurements of the cosmic rays spectrum and composition in the knee area and the primary electrons spectrum by 10 14 - 10 13 eV are discussed. The new effective method for the primary electrons and protons separation with the complex rejection coefficient of 10 -5 - 10 -6 is proposed for studying the primary electrons spectrum by E e > 1 TeV. The experimental and calculation data are in good agreement [ru

HOMA1-IR and HOMA2-IR indexes in identifying insulin resistance and metabolic syndrome - Brazilian Metabolic Syndrome Study (BRAMS)

OpenAIRE

Geloneze, B; Vasques, ACJ; Stabe, CFC; Pareja, JC; Rosado, LEFPD; de Queiroz, EC; Tambascia, MA

2009-01-01

Objective: To investigate cut-off values for HOMA1-IR and HOMA2-IR to identify insulin resistance (IR) and metabolic syndrome (MS), and to assess the association of the indexes with components of the MS. Methods: Nondiabetic subjects from the Brazilian Metabolic Syndrome Study were studied (n = 1,203, 18 to 78 years). The cut-off values for IR were determined from the 9011 percentile in the healthy group (n = 297) and, for MS, a ROC curve was generated for the total sample. Results: In the he...

Comparative study of potentially J{sub eff} = 0 ground state iridium(V) in SrLaNiIrO{sub 6}, SrLaMgIrO{sub 6}, and SrLaZnIrO{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Wolff, Klaus K.; Agrestini, Stefano; Tjeng, Liu Hao [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Tanaka, Arata [Department of Quantum Matter, AdSM, Hiroshima University, Higashi-Hiroshima (Japan); Jansen, Martin [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Max Planck Institute for Solid State Research, Stuttgart (Germany)

2017-12-13

A series of polycrystalline double perovskites SrLaBIrO{sub 6} (B = Ni, Mg, Zn) containing Ir{sup 5+} (5d{sup 4}) was synthesized by solid state reactions, and structural, magnetic and electronic properties were investigated. The isotypic fully ordered double perovskites crystallize in space group P2{sub 1}/n and show semiconducting behavior with estimated bandgaps of approximately 0.2 eV for SrLaNiIrO{sub 6} and SrLaZnIrO{sub 6}, and 0.4 eV for SrLaMgIrO{sub 6}. SrLaNiIrO{sub 6} is an antiferromagnet with a Neel temperature of 74 K (μ{sub eff} = 3.3 μ{sub B}, θ{sub W} = -90 K), whereas SrLaMgIrO{sub 6} and SrLaZnIrO{sub 6} are weakly paramagnetic. All title compounds exhibit a temperature-independent contribution to the measured magnetic susceptibility, which supports the notion for a van-Vleck-type response originating from the Ir{sup 5+} (5d{sup 4}, J{sub eff} = 0) ions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Mid-Infrared Spectral Properties of IR QSOs

International Nuclear Information System (INIS)

Xia, X. Y.; Cao, C.; Mao, S.; Deng, Z. G.

2008-01-01

We analyse mid-infrared (MIR) spectroscopic properties for 19 ultra-luminous infrared quasars (IR QSOs) in the local universe based on the spectra from the Infrared Spectrograph on board the Spitzer Space Telescope. The MIR properties of IR QSOs are compared with those of optically-selected Palomar-Green QSOs (PG QSOs) and ultra-luminous infrared galaxies (ULIRGs). The average MIR spectral features from ∼5 to 30 μm, including the spectral slopes, 6.2 μm PAH emission strengths and [NeII] 12.81 μm luminosities of IR QSOs, differ from those of PG QSOs. In contrast, IR QSOs and ULIRGs have comparable PAH and [NeII] luminosities. These results are consistent with IR QSOs being at a transitional stage from ULIRGs to classical QSOs. We also find the correlation between the EW (PAH 6.2 μm) and outflow velocities suggests that star formation activities are suppressed by feedback from AGNs and/or supernovae.

IGF-IR targeted therapy: Past, present and future

NARCIS (Netherlands)

J.A.M.J.L. Janssen (Joseph); A.J. Varewijck (Aimee)

2014-01-01

textabstractThe IGF-I receptor (IGF-IR) has been studied as an anti-cancer target. However, monotherapy trials with IGF-IR targeted antibodies or with IGF-IR specific tyrosine kinase inhibitors have, overall, been very disappointing in the clinical setting. This review discusses potential reasons

OGTT results in obese adolescents with normal HOMA-IR values.

Science.gov (United States)

Sahin, Nursel Muratoglu; Kinik, Sibel Tulgar; Tekindal, Mustafa Agah

2013-01-01

To investigate insulin resistance (IR) with OGTT in obese adolescents who have normal fasting insulin and homeostasis model assessment for insulin resistance (HOMA-IR). A total of 97 obese adolescents who had values of HOMA-IR IR using an insulin peak of ≥150 μU/mL (1041.8 pmol/L) and/or ≥75 μU/mL (520.9 pmol/L) 120 min after glucose charge and the sum of insulin levels >2083.5 pmol/L (300 μU/mL) in OGTT. IR risk factors were defined as family history of diabetes mellitus, acanthosis nigricans (AN), and hepatic steatosis. IR was detected in 61 (62.9%) patients. The IR group had significantly more frequent AN (p=0.0001). As the number of risk factors increased, the frequency of IR also increased (p=0.01). We advise to perform OGTT in obese adolescents with normal HOMA-IR, if they have risk factors for IR.

Preparation of a novel breviscapine-loaded halloysite nanotubes complex for controlled release of breviscapine

Science.gov (United States)

Gao, Min; Lu, Liqian; Wang, Xiaoyue; Lin, Houke; Zhou, Qingsong

2017-11-01

For sustain the release rate and prolong half-life of breviscapine in vivo, the breviscapine-loaded halloysite nanotubes complex was prepared. The breviscapine was encapsulated into halloysite nanotubes (HNTs) using a vacuum process. The complex were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), transmission electron microscope (TEM), X-ray diffraction (XRD) and fourier transform infrared spectroscopy(FT-IR). The formation of breviscapine-loaded HNTs complex was proved by the test results of SEM, DSC, TEM and IR analysise. The results confirmed that breviscapine was successfully loaded in the halloysite nanotubes. Additionally, the in vitro drug release of breviscapine from breviscapine-loaded HNTs complex was investigated, the result indicated this complex has apparent sustained-release effect.

4PS/insulin receptor substrate (IRS)-2 is the alternative substrate of the insulin receptor in IRS-1-deficient mice.

Science.gov (United States)

Patti, M E; Sun, X J; Bruening, J C; Araki, E; Lipes, M A; White, M F; Kahn, C R

1995-10-20

Insulin receptor substrate-1 (IRS-1) is the major cytoplasmic substrate of the insulin and insulin-like growth factor (IGF)-1 receptors. Transgenic mice lacking IRS-1 are resistant to insulin and IGF-1, but exhibit significant residual insulin action which corresponds to the presence of an alternative high molecular weight substrate in liver and muscle. Recently, Sun et al. (Sun, X.-J., Wang, L.-M., Zhang, Y., Yenush, L. P., Myers, M. G., Jr., Glasheen, E., Lane, W.S., Pierce, J. H., and White, M. F. (1995) Nature 377, 173-177) purified and cloned 4PS, the major substrate of the IL-4 receptor-associated tyrosine kinase in myeloid cells, which has significant structural similarity to IRS-1. To determine if 4PS is the alternative substrate of the insulin receptor in IRS-1-deficient mice, we performed immunoprecipitation, immunoblotting, and phosphatidylinositol (PI) 3-kinase assays using specific antibodies to 4PS. Following insulin stimulation, 4PS is rapidly phosphorylated in liver and muscle, binds to the p85 subunit of PI 3-kinase, and activates the enzyme. Insulin stimulation also results in the association of 4PS with Grb 2 in both liver and muscle. In IRS-1-deficient mice, both the phosphorylation of 4PS and associated PI 3-kinase activity are enhanced, without an increase in protein expression. Immunodepletion of 4PS from liver and muscle homogenates removes most of the phosphotyrosine-associated PI 3-kinase activity in IRS-1-deficient mice. Thus, 4PS is the primary alternative substrate, i.e. IRS-2, which plays a major role in physiologic insulin signal transduction via both PI 3-kinase activation and Grb 2/Sos association. In IRS-1-deficient mice, 4PS/IRS-2 provides signal transduction to these two major pathways of insulin signaling.

FT-IR reflection spectra of single crystals: resolving phonons of different symmetry without using polarised radiation

Directory of Open Access Journals (Sweden)

METODIJA NAJDOSKI

2000-07-01

Full Text Available Fourier-transform infrared (FT-IR reflection spectra, asquired at nearnormal incidence, were recorded from single crystals belonging to six crystal systems: CsCr(SO42.12H2O (alum, cubic, K2CuCl2·2H2O (Mitscherlichite, tetragonal, CaCO3 (calcite, hexagonal, KHSO4 (mercallite, orthorhombic, CaSO4·2H2O (gypsum, monoclinic and CuSO4·5H2O (chalcantite, triclinic. The acquired IR reflection spectra were further transformed into absorption spectra, employing the Kramers-Kronig transformation. Except for the cubic alums, the spectra strongly depend on the crystal face from which they were recorded; this is a consequence of anisotropy. Phonons of a given symmetry (E-species, in tetragonal/hexagonal and B-species, in monoclinic crystals may be resolved without using a polariser. The spectrum may be simplified in the case of an orthorhombic crystal, as well. The longitudinal-optical (LO and transversal-optical (TO mode frequencies were calculated in the case of optically isotropic and the simplified spectra of optically uniaxial crystals.

Characterisation of 1,3-diammonium propylselenate monohydrate by XRD, FT-IR, FT-Raman, DSC and DFT studies

Science.gov (United States)

Thirunarayanan, S.; Arjunan, V.; Marchewka, M. K.; Mohan, S.; Atalay, Yusuf

2016-03-01

The crystals of 1,3-diammonium propylselenate monohydrate (DAPS) were prepared and characterised X-ray diffraction (XRD), FT-IR, FT-Raman spectroscopy, and DFT/B3LYP methods. It comprises protonated propyl ammonium moieties (diammonium propyl cations), selenate anions and water molecule which are held together by a number of hydrogen bonds and form infinite chains. The XRD data confirm the transfer of two protons from selenic acid to 1,3-diaminopropane molecule. The DAPS complex is stabilised by the presence of O-H···O and N-H···O hydrogen bonds and the electrostatic interactions as well. The N···O and O···O bond distances are 2.82-2.91 and 2.77 Å, respectively. The FT-IR and FT-Raman spectra of 1,3-diammonium propyl selenate monohydrate are recorded and the complete vibrational assignments have been discussed. The geometry is optimised by B3LYP method using 6-311G, 6-311+G and 6-311+G* basis sets and the energy, structural parameters, vibrational frequencies, IR and Raman intensities are determined. Differential scanning colorimetry (DSC) data were also presented to analyse the possibility of the phase transition. Complete natural bonding orbital (NBO) analysis is carried out to analyse the intramolecular electronic interactions and their stabilisation energies. The electrostatic potential of the complex lies in the range +1.902e × 10-2 to -1.902e × 10-2. The limits of total electron density of the complex is +8.43e × 10-2 to -8.43e × 10-2.

Growth and phase transformations of Ir on Ge(111)

Science.gov (United States)

Mullet, C. H.; Stenger, B. H.; Durand, A. M.; Morad, J. A.; Sato, Y.; Poppenheimer, E. C.; Chiang, S.

2017-12-01

The growth of Ir on Ge(111) as a function of temperature between 23 °C and 820 °C is characterized with low energy electron microscopy (LEEM), low energy electron diffraction (LEED), scanning tunneling microscopy (STM), and x-ray photoemission spectroscopy (XPS). Deposition onto a substrate at 350 °C revealed a novel growth mode consisting of multilayer Ir islands with (√3 × √3)R30° (abbreviated as √3) structure interconnected by ;bridges; of single-layer Ir several atoms wide. For deposition onto substrates above 500 °C, the √3 Ir phase grows with dendritic morphology, and substrate step bunches act as barriers to √3 Ir growth. LEEM images showed Stranski-Krastanov growth for 650-820 °C: after the √3 phase covers the surface, corresponding to 2 monolayers (ML) Ir coverage, multilayer hexagonal-shaped Ir islands form, surrounded by regions of IrGe alloy. Hexagonal-shaped Ir islands also formed upon heating 1.2 ML of √3 Ir beyond 830 °C, which resulted in the elimination of √3 structure from the surface. The transformation from √3 to (1 × 1) structure upon heating to 830 °C was an irreversible surface phase transition. Annealing > 2.0 ML of Ir in the √3 phase above the 830 °C disorder temperature, followed by cooling, produced a (3 × 1) structure. Subsequent heating and cooling through 830 °C give evidence for a reversible (3 × 1) to (1 × 1) phase transition.

Using near infrared spectrum analysis to predict water and chlorophyll content in tomato leaves

Science.gov (United States)

Jiang, Huanyu; Ying, Yibin; Liu, Yande

2004-11-01

In this study, we developed a nondestructive way to analyze water and chlorophyll content in tomato leaves. A total of 200 leaves were collected as experimental materials, 120 of them were used to form a calibration data set. Drying chest, SPAD meter and NIR spectrometer were used to get water content, chlorophyll content and spectrums of tomato leaves respectively. The Fourier Transform Infrared (FTNIR) method with a smart Near-IR Updrift was used to test spectrums, and partial least squares (PLS) technique was used to analyze the data we get by normal experimentation and near infrared spectrometer, set up a calibration model to predict the leaf water and chlorophyll content based on the characteristics of diffuse reflectance spectrums of tomato leaves. Three different mathematical treatments were used in spectrums processing: different wavelength range, different smoothing points, first and second derivative. We can get best prediction model when we select full range (800-2500nm), 3 points for spectrums smoothing and spectrums by baseline correction, the best model of chlorophyll content has a root mean square error of prediction (RMSEP) of 8.16 and a calibration correlation coefficient (R2) value of 0.89452 and the best model of water content has a root mean square error of prediction (RMSEP) of 0.0214 and a calibration correlation coefficient (R2) value of 0.91043.

Biochemical applications of FT-IR spectroscopy

NARCIS (Netherlands)

Pistorius, A.M.A.

1996-01-01

This thesis describes the use of (FT-)IR spectroscopy in general biochemical research. In chapter 3, IR spectroscopy is used in the quantitation of residual detergent after reconstitution of an integral membrane protein in a pre-defined lipid matrix. This chapter discusses the choice of the

Future development of IR thermovision weather satellite equipment

Science.gov (United States)

Listratov, A. V.

1974-01-01

The self radiation of the surface being viewed is used for image synthesis in IR thermovision equipment. The installation of such equipment aboard weather satellites makes it possible to obtain cloud cover pictures of the earth's surface in a complete orbit, regardless of the illumination conditions, and also provides quantitative information on the underlying surface temperature and cloud top height. Such equipment is used successfully aboard the Soviet satellites of the Meteor system, and experimentally on the American satellites of the Nimbus series. With regard to surface resolution, the present-day IR weather satellite equipment is inferior to the television equipment. This is due primarily to the comparatively low detectivity of the IR detectors used. While IR equipment has several fundamental advantages in comparison with the conventional television equipment, the problem arises of determining the possibility for future development of weather satellite IR thermovision equipment. Criteria are examined for evaluating the quality of IR.

Irradiation characteristics of metal-cluster-complex ions containing diverse multi-elements with large mass differences

International Nuclear Information System (INIS)

Fujiwara, Yukio; Kondou, Kouji; Teranishi, Yoshikazu; Nonaka, Hidehiko; Saito, Naoaki; Fujimoto, Toshiyuki; Kurokawa, Akira; Ichimura, Shingo; Tomita, Mitsuhiro

2007-01-01

Tetrairidium dodecacarbonyl, Ir 4 (CO) 12 , is a metal cluster complex which has a molecular weight of 1104.9. Using a metal-cluster-complex ion source, the interaction between Ir 4 (CO) n + ions (n=0-12) and silicon substrates was studied at a beam energy ranging from 2keV to 10keV at normal incidence. By adjusting Wien-filter voltage, the influence of CO ligands was investigated. Experimental results showed that sputtering yield of silicon bombarded with Ir 4 (CO) n + ions at 10keV decreased with the number of CO ligands. In the case of 2keV, deposition tended to be suppressed by removing CO ligands from the impinging cluster ions. The influence of CO ligands was explained by considering changes in surface properties caused by the irradiation of Ir 4 (CO) n + ions. It was also found that the bombardment with Ir 4 (CO) 7 + ions at 2.5keV caused deposition on silicon target

Experimental techniques for the consolidation of the neutron spectrum

International Nuclear Information System (INIS)

Chiaraviglio, N.; Bazzana, S.

2013-01-01

Unfolding techniques are widely known but their use is not widespread due to their complexity. Such procedure consists in the adjustment of calculated quantities to experimental results by the modification of the neutron spectrum, getting correction factors for the calculated quantities. In this work we describe the general procedure that must be executed for a neutron spectrum unfolding. (author) [es

A Novel Approach for Transmission of 56 Gbit/s NRZ Signal in Access Network Using Spectrum Slicing Technique

DEFF Research Database (Denmark)

Spolitis, S.; Vegas Olmos, Juan José; Bobrovs, V.

2013-01-01

We present the spectrum slicing and stitching concept for high-capacity low optics complexity optical access networks. Spectrum slicing and stitching of a 56 Gbit/s NRZ electrical signal is experimentally demonstrated for the first time.......We present the spectrum slicing and stitching concept for high-capacity low optics complexity optical access networks. Spectrum slicing and stitching of a 56 Gbit/s NRZ electrical signal is experimentally demonstrated for the first time....

Piperazine complexes of some lanthanides and actinides

Energy Technology Data Exchange (ETDEWEB)

Manhas, B S; Trikha, A K [Punjabi Univ., Patiala (India). Dept. of Chemistry; Singh, M [Guru Nanak Univ., Amritsar (India). Dept. of Chemistry

1981-02-01

Complexes of piperazine with LaCl/sub 3/, CeCl/sub 3/, La(NO/sub 3/)/sub 3/, Ce(NO/sub 3/)/sub 3/, UO/sub 2/(OAc)/sub 2/, UO/sub 2/Cl/sub 2/, UO/sub 2/(NO/sub 3/)/sub 2/, UCl/sub 4/, ThCl/sub 4/ and Th(NO/sub 3/)/sub 4/ have been synthesized and characterized on the basis of elemental analyses, IR and electronic reflectance spectra and magnetic susceptibility measurements. IR data indicate (i) coordination of the ligand in the chair form (except in the case of uranyl chloride complex where at least some of the ligand molecules are present in boat conformation), (ii) coordination of the ethanol and methanol molecules and (iii) the presence of chelating bidentate acetate and nitrate groups.

Synthesis and study on complexes of some lanthanides to L-isoleucine

International Nuclear Information System (INIS)

Le Minh Tuan; Pham Minh Tuan; Tran The Dinh

2007-01-01

The formation of lanthanide (La, Pr and Nd) complexes with L-isoleucine have been studied as a function of pH values. The titrations were performed at 25 o C, and the ionic strength of the medium was maintained at 0.10 M by using potassium nitrate. The formation curves of their complexes (n-p[L]) were obtained by means of the titration data. Then the stability constants were determined in relation to these curves. The complexes were synthesized in the mixture of water-ethanol. The coordination of the complexes were determined by elements analysis, 13 C-NMR, 1 H-NMR and IR methods. These complexes are formulated as Ln(HIle) 3 .(NO 3 ) 3 .3H 2 O; (Ln: La, Pr and Nd,; L-Ile: L-isoleucine). Comparison of the IR, 13 C-NMR and 1 H-NMR spectra of the ligand with those of their complexes shows that isoleucine acts as a bidentate ligand bonding the lanthanide ions through the amino and carboxylate groups. (author)

Electrochemistry of transition metal complex catalysts. Part 9. One- and two-electron oxidation of iridium complexes with cyclohexane-derived tripod phosphine ligands

International Nuclear Information System (INIS)

Buchmann, Silke; Mayer, Hermann A.; Speiser, Bernd; Seiler, Michael; Feth, Martin P.; Bertagnolli, Helmut; Steinbrecher, Stefan; Plies, Erich

2003-01-01

The redox chemistry of Ir tripod-type tri-phosphine complexes in dichloromethane is investigated by cyclic voltammetry, hold-ramp experiments, and preparative electrolysis at Pt electrodes. Products are identified by spectroscopic data, as well as EDX and EXAFS results. Complexes with the Ir central atom in the oxidation states +I, +II and +III are detected and several follow-up reactions are possible from those. Most of the intermediates and products are characterized. In particular, experiments in the presence of CO contribute to the assignment of peaks in the cyclic voltammograms. The experimental results for the individual steps are summarized in a comprehensive redox reaction mechanism (mesh scheme) for which most steps are characterized by redox potentials

Investigation of a van der Waals complex with C 1 symmetry: the free-jet rotational spectrum of 1,2-difluoroethane-Ar

Science.gov (United States)

Melandri, Sonia; Velino, Biagio; Favero, Paolo G.; Dell'Erba, Adele; Caminati, Walther

2000-04-01

The van der Waals complex between Ar and 1,2-difluoroethane has been investigated by free-jet absorption millimeter-wave spectroscopy in the frequency range 60-78 GHz. The analysis of the spectroscopic constants derived from the rotational spectrum allowed the determination of the dimer's structure. 1,2-Difluoroethane is in the gauche conformation and the Ar atom is in a position stabilized by the interaction with one fluorine and the two carbon atoms. The distance between Ar and the center of mass (CM) of the monomer is 3.968 Å, the angle between the Ar-CM line and the C-C bond is 65° and the dihedral angle Ar-CM-C-C is 99°. From centrifugal distortion effects the dissociation energy of the complex has been estimated to be 2.1 kJ/mol.

Synthesis and X-ray crystal structure of a novel organometallic (µ(3)-oxido)(µ(3)-imido) trinuclear iridium complex

DEFF Research Database (Denmark)

Schau-Magnussen, Magnus; Malcho, Phillip; Herbst, Konrad

2011-01-01

Reaction of the organometallic aqua ion [Cp*Ir(H(2)O)(3)](2+) with tert-butyl(trimethylsilyl)amine in acetone yielded a novel trinuclear (µ(3)-oxido)(µ(3)-imido)pentamethylcyclopentadienyliridium(iii) complex, [(Cp*Ir)(3)(O)(N(t)Bu)](2+). Single crystal structure analyses show the complex can be ...... that a trinuclear (µ(3)-oxido)(µ(3)-imido) transition metal complex has been structurally characterized....

IR Cards: Inquiry-Based Introduction to Infrared Spectroscopy

Science.gov (United States)

Bennett, Jacqueline; Forster, Tabetha

2010-01-01

As infrared spectroscopy (IR) is frequently used in undergraduate organic chemistry courses, an inductive introduction to IR spectroscopy that uses index cards printed with spectra, structures, and chemical names is described. Groups of students are given an alphabetized deck of these "IR cards" to sort into functional groups. The students then…

Quantitative gas analysis with FT-IR

DEFF Research Database (Denmark)

Bak, J.; Larsen, A.

1995-01-01

Calibration spectra of CO in the 2.38-5100 ppm concentration range (22 spectra) have been measured with a spectral resolution of 4 cm(-1), in the mid-IR (2186-2001 cm(-1)) region, with a Fourier transform infrared (FT-IR) instrument. The multivariate calibration method partial least-squares (PLS1...

Validity and reproducibility of HOMA-IR, 1/HOMA-IR, QUICKI and McAuley's indices in patients with hypertension and type II diabetes.

Science.gov (United States)

Sarafidis, P A; Lasaridis, A N; Nilsson, P M; Pikilidou, M I; Stafilas, P C; Kanaki, A; Kazakos, K; Yovos, J; Bakris, G L

2007-09-01

The aim of this study was to evaluate the validity and reliability of homeostasis model assessment-insulin resistance (HOMA-IR) index, its reciprocal (1/HOMA-IR), quantitative insulin sensitivity check index (QUICKI) and McAuley's index in hypertensive diabetic patients. In 78 patients with hypertension and type II diabetes glucose, insulin and triglyceride levels were determined after a 12-h fast to calculate these indices, and insulin sensitivity (IS) was measured with the hyperinsulinemic euglycemic clamp technique. Two weeks later, subjects had again their glucose, insulin and triglycerides measured. Simple and multiple linear regression analysis were applied to assess the validity of these indices compared to clamp IS and coefficients of variation between the two visits were estimated to assess their reproducibility. HOMA-IR index was strongly and inversely correlated with the basic IS clamp index, the M-value (r=-0.572, PHOMA-IR and QUICKI indices were positively correlated with the M-value (r=0.342, PHOMA-IR was the best fit of clamp-derived IS. Coefficients of variation between the two visits were 23.5% for HOMA-IR, 19.2% for 1/HOMA-IR, 7.8% for QUICKI and 15.1% for McAuley's index. In conclusion, HOMA-IR, 1/HOMA-IR and QUICKI are valid estimates of clamp-derived IS in patients with hypertension and type II diabetes, whereas the validity of McAuley's index needs further evaluation. QUICKI displayed better reproducibility than the other indices.

Complexes of molybdenum(III) with 2-(2'-pyridyl)benzimidazole

International Nuclear Information System (INIS)

Ghosh, S.P.; Prasad, K.M.

1979-01-01

Molybdenum(III) forms with 2-(2'-pyridyl) benzimidazole(LH) the trischelated complexes, [Mo(LH) 3 ]X 3 as well as the cationic-anionic complexes, [Mo(LH) 3 X 2 ] + [Mo(LH)X 4 ] - (X=Cl - ,Br - or NCS - ), depending on pH. These complexes have been synthesised and characterised from elemental analyses, i.r. and electronic spectra, magnetic moments and molar conductance. (auth.)

IR sensor for monitoring of burner flame; IR sensor foer oevervakning av braennarflamma

Energy Technology Data Exchange (ETDEWEB)

Svanberg, Marcus; Funkquist, Jonas; Clausen, Soennik; Wetterstroem, Jonas

2007-12-15

To obtain a smooth operation of the coal-fired power plants many power plant managers have installed online mass flow measurement of coal to all burners. This signal is used to monitor the coal mass flow to the individual burner and match it with appropriate amount of air and also to monitor the distribution of coal between the burners. The online mass flow measurement system is very expensive (approximately 150 kEUR for ten burners) and is not beneficial for smaller plants. The accuracy of the measurement and the sample frequency are also questionable. The idea in this project has been to evaluate a cheaper system that can present the same information and may also provide better accuracy and faster sample frequency. The infrared sensor is a cheap narrow banded light emission sensor that can be placed in a water cooed probe. The sensor was directed at the burner flame and the emitted light was monitored. Through calibration the mass flow of coal can be presented. Two measurement campaigns were performed. Both campaigns were carried out in Nordjyllandsverket in Denmark even though the second campaign was planned to be in Uppsala. Due to severe problems in the Uppsala plant the campaign was moved to Nordjyllandsverket. The pre-requisites for the test plant were that online measurement of coal flow was installed. In Nordjyllandsverket 4 out of 16 burners have the mass flow measurement installed. Risoe Laboratories has vast experiences in the IR technology and they provided the IR sensing equipment. One IR sensor was placed in the flame guard position just behind the flame directed towards the ignition zone. A second sensor was placed at the boiler wall directed towards the flame. The boiler wall position did not give any results and the location was not used during the second campaign. The flame-guard-positioned-sensor- signal was thoroughly evaluated and the results show that there is a clear correlation between the coal mass flow and the IR sensor signal. Tests were