108 research outputs found
Hydrido complexes of iridium with a tertiary arsine
α-​and β-​IrHX2(Ph2AsMe)​3 (X = Cl, Br, I) were prepd. and characterized. The α-​compds. were prepd. by treating the IrX3 in the arsine in alc. with Zn and the corresponding HX; while the β-​compds. were prepd. by refluxing IrX3 and the arsine in alc. in the presence of KOH. The compds. were characterized by m.p. and ir spectra
Reactions of rhodium and iridium salts with multidentate N-heterocycles
Complexes of rhodium and iridium of the types MX3L, MX(CO)2L and MX3(CO)L (X = halide) containing multidentate N-heterocycles (L), 2,6-bis(benzimidazolyl)pyridine (bBzlH2py) and 2,6-bis(N-methyl-benzimidazolyl)pyridine (bBzlMe2py) have been prepared and characterized by IR, electronic and 1H and 13C NMR spectral data. RhX(CO)2L, on treatment with alcoholic solvents or DMF undergoes reversible decarbonylation to produce RhXL·2H2O. Passage of NO or O2 through the carbonyl suspended in hot 2-methoxyethanol releases CO2. Copyright © 1997 Elsevier Science Ltd
Cyclometallation of bis-benzimidazole derivatives with rhodium(III) halides
Treatment of rhodium(III) halides with the N-heterocycles (LH), 1,3-bis(benzimidazolyl)benzene (bBzlH2bzH; Ia) and its N-methyl derivative (bBzlMe2bzH; Ib) in methanol gave halobridged binuclear cyclometallated products of the composition RhX2L2 (X=Cl, Br or I). The chloro complex undergoes halobridge cleavage reactions to yield several new mononuclear complexes of the types RhCl2(bBzlH2bz)(AsPh3), RhCl(bBzlH2bz)(OClO3)(Lâ²/N-N) (Lâ²=AsPh3; N-N=2,2â²-bipyridine or 1,10-phenanthroline) and the heterocycle bridged binuclear complexes of the composition RhCl2(bBzlH2bz)2(μ-N-N) (N-N=pyrazine or 4,4â²-bipyridine). Passage of CO through RhCl2(bBzlH2bz)2 in DMF yielded mononuclear carbonyl complex RhCl2(CO)(bBzlH2bz)·2H2O. Treatment of carbonylated solution of rhodium trichloride with Ia produced non-cyclometallated mononuclear complex of the type Rh(CO)2(bBzlH2bzH)Cl. The complexes are characterised by 1H, 13C NMR, IR, Far-IR, electronic and FAB-mass spectral studies. © Elsevier Science Ltd
Complexes of osmium with tertiary arsines and carbonmonoxide
Osmium halides (Cl and Br) react with monotertiary arsines Ph2RAs (R=Me, Et, Pr and Bu) in alcoholic medium to give paramagnetic octahedral complexes of the type OsX3L3 (X=Cl, Br; L=Ph2RAs) which further react with carbonmonoxide to give dihalo dicarbonyl complexes of osmium(II) of the type OsX2 (CO)2 L2. Similarly, osmium halides react with tertiary arsines in the presence of formaldehyde to give monocarbonyl complexes of osmium(II) of the type OsX2 (CO)L3. Structures have been assigned to all these compounds on the basis of IR and NMR studies. © 1980 Indian Academy of Sciences
Enhancement of Exon Regions Recognition in Gene Sequences Using a Radix -4 Multi-valued Logic with DSP Approach
Numerous levels of concepts perform logical designand logical representations in an efficient manner. In typical and quantum theories of
computation, Binary logic and Boolean algebra occupies an imperative place. But they havethe limitation of representing signals or sequences by using either
binary ‘1’ or ‘0’. This has major drawbacks that the neutralities or any intermediate values are ignored which are essential in most of the applications.
Because of the occurrence of such situations it is the need of the hour to look into other alternative logics in order to fulfill the necessities of the user
in their respective applications. The binary logic can be replaced by Multi-Valued Logic (MVL), which grabs the positions of the major applications because
of the ability to provide representation by using more than two values.As most of the significant applications are based on the logical sequences, the
multi-valued logic shines because of its thriving feature. Genomic signal processing, a novel research area in bioinformatics,is one of the foremost
applications which involve the operations of logical sequences. It is concerned with the digital signal representations and analysis of genomic
data.Determination of the coding region in DNA sequence is one of the genomic operations.This leads to the identification of the characteristics of the gene
which in turn finds out an individual’s behavior. In order to extract the coding regions on the basis of logical sequences a number of techniques have been
proposed by researchers. But most of the works utilized binary logic, which lead to the problem of losing some of the coding regions and incorrectly
recognizing non-coding regions as the coding regions. Hereby,we are proposing an approach for recognizing the exon regions from a gene sequence based on the
multi-valued logic. In this approach, we have utilized fourlevel logical system, termed as quaternary logic for the representation of gene sequences and so that we recognize theexon regions from the DNA sequence
Spectroscopic Coronal Observations during the Total Solar Eclipse of 11 July 2010
The flash spectrum of the solar chromosphere and corona was measured with a
slitless spectrograph before, after, and during the totality of the solar
eclipse, of 11 July 2010, at Easter Island, Chile. This eclipse took place at
the beginning of the Solar Cycle 24, after an extended minimum of solar
activity. The spectra taken during the eclipse show a different intensity ratio
of the red and green coronal lines compared with those taken during the total
solar eclipse of 1 August 2008, which took place towards the end of the Solar
Cycle 23. The characteristic coronal forbidden emission line of forbidden Fe
XIV (5303 {\AA}) was observed on the east and west solar limbs in four areas
relatively symmetrically located with respect to the solar rotation axis.
Subtraction of the continuum flash-spectrum background led to the
identification of several extremely weak emission lines, including forbidden Ca
XV (5694 {\AA}), which is normally detected only in regions of very high
excitation, e.g., during flares or above large sunspots. The height of the
chromosphere was measured spectrophotometrically, using spectral lines from
light elements and compared with the equivalent height of the lower
chromosphere measured using spectral lines from heavy elements.Comment: 14 pages, 8 figures, 1 table; Solar Physics, 2012, Februar
Reproducibility in the absence of selective reporting : An illustration from large-scale brain asymmetry research
Altres ajuts: Max Planck Society (Germany).The problem of poor reproducibility of scientific findings has received much attention over recent years, in a variety of fields including psychology and neuroscience. The problem has been partly attributed to publication bias and unwanted practices such as p-hacking. Low statistical power in individual studies is also understood to be an important factor. In a recent multisite collaborative study, we mapped brain anatomical left-right asymmetries for regional measures of surface area and cortical thickness, in 99 MRI datasets from around the world, for a total of over 17,000 participants. In the present study, we revisited these hemispheric effects from the perspective of reproducibility. Within each dataset, we considered that an effect had been reproduced when it matched the meta-analytic effect from the 98 other datasets, in terms of effect direction and significance threshold. In this sense, the results within each dataset were viewed as coming from separate studies in an "ideal publishing environment," that is, free from selective reporting and p hacking. We found an average reproducibility rate of 63.2% (SD = 22.9%, min = 22.2%, max = 97.0%). As expected, reproducibility was higher for larger effects and in larger datasets. Reproducibility was not obviously related to the age of participants, scanner field strength, FreeSurfer software version, cortical regional measurement reliability, or regional size. These findings constitute an empirical illustration of reproducibility in the absence of publication bias or p hacking, when assessing realistic biological effects in heterogeneous neuroscience data, and given typically-used sample sizes
Prevenção de injúrias causadas por glyphosate em soja RR por meio do uso de aminoácido
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