Schiff base condensation of benzil bis(hydrazone) with formaldehyde, acetone and benzaldehyde and its nickel(II) complexes were synthesised. Preparation of the free ligands was accomplished by refluxing benzil with hydrazine derivatives in 1:10 mole ratios in ethylene glycol. The spectral characterisation of hydrazone based 14-membered octaaza macrocyclic complexes of nickel(II) was undertaken. The ligand, benzil bis(hydrazone) and complexes were characterized by FTIR, UV-visible, 1 H NMR, Mass spectroscopy. The results of the investigations support the formulation of each of the complexes as a metal ion surrounded by a planar, quadradentate ligand. Thus, the data provide strong support for the conclusion that the macrocyclic complexes were actually prepared.
In conclusion, the synthesis and spectroscopic investigation of Schiff base transition metal complexes have been reported herein. The spectral data concluded the tetradentate nature of the Schiff base ligand and the complexes are four coordinated and the complexes were found to be non-electrolyte. The in-vitro investigation of the synthesized complex revealed that all the complexes showed very good results against the selected micro organisms under investigation. The experimental result regarding Inhibition Efficiency of the Schiff base metal complexes under study reveals that the compounds have inhibition property. They inhibit the oxidation of metal in acid medium. The inhibition of metal corrosion may be due to adsorption of added the ligand and metal chelates.
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presence of a penta-coordinated heme NO complex. The minor variations in these spectra can be attributed to differences in protein conformation or pigment concen- tration, and to a different degree of hydration, which is higher for cooked, brine-cured ham compared to dry- cured Serrano ham. Likewise, substantial differences in low-temperature ESR spectra of MbFe(II)NO in either raw or heat-treated bacon have previously been reported . It is accordingly safe to conclude from the ESR spectra that the myoglobin derivative present in fully matured Parma ham is not a nitrosylated form of myoglobin, as has been suggested to be formed as a result of microbial activity . It should also be noted that if bacteria were responsible for colour formation, the colour hue and intensity in the centre of the ham most likely would be different from the hue and intensity at the surface zone, in contrast to what is observed for Parma ham. Given the increasing amounts of salt and reduced moisture content during processing of dry-cured hams, the formation of hemichrome (a denatured low-spin form of ferric myoglobin) could occur, in which the 6th ligand most likely is histidine or another amino acid from globin, e.g. methionine. These inactivated complexes of myoglo- bin are paramagnetic and thus detectable by ESR spectroscopy. The applied temperature is especially critical and in order to obtain a signal it should be at least 77 K or below . Therefore, based on the present ESR experiments, it cannot be ruled out that hemichrome is absent in matured Parma ham. However, as will be observed later, the absorption spectral characteristics of pigments isolated from Parma ham show no resemblance to purified hemichromes .
This Letter evaluates, for the first time, the power spectral density (PSD) of n k -PPM. By making use of the cyclostationary properties of the modulation format, original expressions are derived for predicting both the continuous and discrete spectrum and these are verified numerically by taking the Fast Fourier Transform of the n k -PPM pulse stream.
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Conventionally, EEG analysis mostly relies on visual inspection of relevant EEG signals. In many cases, however, visual inspection of EEG signals may be subjective and insufficient because statistical information contained in EEG signals may not be adequately exploited and utilised. To obtain more relatively objective and reliable analysis results, several methods have been proposed for quantitative analysis of EEG signals. Among these, the Fourier transform based algorithms are the most commonly used tool for revealing the frequency components of EEG signals. The Fourier transform, however, has some disadvantages for dealing with non-stationary EEG signals. Therefore, other parametric and non-parametric spectral estimation methods have been proposed for EEG signal analysis (Gersch and Yonemoto, 1977; Isaksson, 1981; Pascualmarqui et al., 1988; Tseng et al., 1995; Pardey et al., 1996; Muthuswamy and Thakor, 1998; Quiroga et al., 1997, 2002, Guler et al., 2001; Panzica et al., 2003; Subasi, 2007; Zhou et al., 2008).
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9,10-Phenanthrenequinone and benzylamine were purchased from Sigma Aldrich and used as such. Co(II), Ni(II), Cu(II) and Zn(II) metal salts were of analytical grade from Merck. All other reagents and solvents were purchased from commercial sources and were of analytical grade and were purified by distillation. Elemental analysis was recorded on a Carlo Erba model 1106 elemental analyzer. The infrared spectra of the solid samples were recorded in Perkin Elmer spectrometer in the range of 4000-400 cm -1 . Potassium bromide disc method was employed for sample preparation. Electronic spectra were recorded using Perkin Elmer Lambda-35 UV-Vis. spectrometer using DMSO as solvent in the range of 200-800 nm. The molar conductivity measurements of the metal complexes were carried out in ~10 -3 M DMSO solutions using a Coronation digital conductivity meter. The 13 C NMR was recorded on a JEOL GSX-400 spectrometer employing CDCl 3 as solvent at ambient temperature. The mass spectral analysis was carried
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With v 1 giving the value of Δ or 10Dq directly. In some of eth Ni(II) Oh complexes, a weak spin-forbidden absorption (triplet → singlet ¹E g ← ³A 2g ) may be found due to the influence of spin-orbit coupling in mixing of a spin singlet (¹Eg) with the spin triplet [³T 1g (F)] term. The spectra of all Ni(II) complexes show three absoroption with any shoulder around two absorption. The spectral data has been used to evaluate the parameters using the relationship 18,19 . To calculate the energies of the
Azomethine group (–C=N–) containing compounds typically known as Schiff bases have been synthesised by the condensation of primary amines with active carbonyls. Schiff bases form a significant class of compounds in medicinal and pharmaceutical chemistry with several biological applications that include antibacterial, antifungal [1- 6] and antitumor activity [7,8]. 4-Oxo-thiazolidinones are synthesised either by cyclisation of acyclic compounds or by interconversation among appropriately substituted thiazolidine derivatives. The 4-oxo-thiazolidine ring system comprises the broad spectrum for a number of biologically active compounds. In recent years, 4-oxo-thiazolidine are the most extensively investigated class of compounds, which exhibit various biological activities, such as antimicrobial, anti-inflammatory, anti-HIV, anti-toxoplasma, gondii, antitubercular, antioxidant, and analgesic [9– 17]. Different method for the preparation of 4-oxo-thiazolidines have been reported [18-19]. In continuation of our works on 4-thiazolidinone derivatives [20-23], we have undertaken the synthesis of 4-oxo-thiazolidines of type (3a- e) by the condensation of schiff-bases (2a-e) with thioglycolic acid. Cyclocondensation of schiff-bases (2a-e) with thiolactic yielded 4-oxo-thiazolidines of type (4a-e). All the synthesised compounds were confirmed on the basis of their spectral data and physical data.
www.wjpr.net Vol 7, Issue 8, 2018. 317 the binuclear complexes. The binding sites are the azomethine nitrogen atoms and the phenolic oxygen atoms respectively. The bonding of ligand to metal ion is confirmed by elemental analyses, spectral studies like UV–Vis, FT-IR, NMR, ESR and conductance measurements. The molar conductance values reveal that the complexes were 1:1 electrolytic nature of the complexes. The cyclic voltammogram of the complexes confirmed the redox property. From the analytical and spectral data, all the copper(II) complexes were shown to exhibit a square planar geometry. The binding behaviour of metal complexes with DNA was studied by UV absorption spectra which indicate that all the three synthesized complexes can strongly bind to CT-DNA via an intercalation mode. Antibacterial and antifungal studies of the ligand and complexes have also been studied which indicate that activity increases on chelation. Based on the results obtained from the spectral data, the structure of the ligand and its complexes are proposed as follows.
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COMA and COMA++ are implementation frameworks and do not include a process covering the entire ontology mapping lifecycle. COMA++ does support some activities of a management phase of the lifecycle. However, COMA++ does not support the core of the characterisation phase where the difficulty expected in mapping is evaluated. The original COMA system has shown however that a flexible matching architecture can be employed successfully to the schema-matching problem. Research has shown how the COMA system compares very favourably in terms of accuracy of match results, with respect to seven other schema-matching systems in an evaluation of authors’ claims (Do et al. 2002), and with respect to Cupid (Madhavan et al. 2001) and Similarity Flooding (Melnik et al. 2002) in an independent evaluation (Yatskevich 2003). COMA++ promises an equally flexible matching architecture for ontologies but with additional features for mapping manipulation. In particular the clear separation between match and mapping generation offers the possibility for these steps to be done at separate times, resulting in more relevant mappings. However, the claim of the developers of the system, that it solves most problems of the EON 2004 ontology alignment contest with high accuracy, has yet to be independently verified. No evaluation has been published showing how the system compares in terms of reduction of effort and/or error rates of users. It is difficult to evaluate the substitutability features of the system as it has not been made publicly available for use. From the literature it is difficult to assess whether the Graphical User Interface incorporates any particular features beyond numeric similarity metrics that aid the user in evaluating whether suggested candidate matches or mappings should be altered or discarded.
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A drive towards leaner engineering has seen the use of physical prototypes become a limiting factor in the development of new products. Consequently, alternative pro- totyping methods are of interest. With their ability to reduce cost, accelerate time to market, and optimize products to higher levels of performance and reliability, vir- tual methods oer an attractive alternative. Methods for virtual prototyping with respect to visual design and engineering (i.e CAD and CAE) are particularly well developed. Unfortunately, the same cannot be said in the realm of acoustics. Al- though numerical methods, such as nite and boundary element analysis, are able to predict, with some accuracy, the passive properties of simple assembly components, they currently lack the ability to accurately model more complex vibro-acoustic com- ponents, for example vibration sources and their associated vibratory mechanisms. Consequently, the adoption of any virtual acoustic prototyping (VAP) methodol- ogy will require some element of experimental work. As such, this Thesis concerns the development and implementation of experimental methods for the independent characterisation of assembly components, with particular emphasis on in-situ ap- proaches. The methods discussed in this work will focus on the determination of active and passive sub-structure properties that may be recombined virtually within a dynamic sub-structuring framework so as to construct a VAP. A well constructed VAP will allow for an engineer to `listen' to a product without it having to phys- ically exist. With the growing importance of product sound quality, this oers a considerable advantage, particularly in the early stages of product development. Work begins by developing an in-situ method for the independent characterisation of resilient coupling elements. The approach holds a number of advantages over current methods as it may be applied to arbitrary structures and over a wide frequency range. In order to provide a exible and workable method that may be used in a practical scenario three experimental extensions are provided. These extensions concern; the nite dierence approximation for rotational degrees of freedom, the round trip identity for remote measurement positions, and generalised transmissibility for the use of operationally determinable quantities. Experimental studies show that the proposed method, and its extensions, are capable of determining the independent
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Production and characterisation of porous hydroxyapatite Suzanne Calicut phosphate based glass at high temperatures. The liquid phase acted on the hydroxyapatite by reducing the interfacial energy and promoting the kinetics of the sintering process through faster atomic diffusion. As a result of chemical reactions TCP phases were formed and porosity eliminated. There was also an improvement in mechanical properties at 1250°C. However, micro-structural coarsening took place at 1350°C, which explained the decrease in fracture toughness that was seen at 1350°C. No difference in mechanical properties was found between the 2.5 and the 5 wt% additions of glass. The 2.5wt% therefore seemed to be the optimal glass addition required to minimise the reactive liquid phase present at the grain boundary but at the same time be sufficient to fully sinter the hydroxyapatite.
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Please cite this article as: Spencer, C.S., Yunta, C., Gomes de Lima, G.P., Hemmings, K., Lian, L.-Y., Lycett, G., Paine, M.J.I., Characterisation of Anopheles gambiae heme oxygenase and metalloporphyrin feeding suggests a potential role in reproduction, Insect Biochemistry and Molecular Biology (2018), doi: 10.1016/j.ibmb.2018.04.010.
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Risk characterisation combines the data on hazard and exposure in order to assess the likely risk to human health. Default factors are often used to provide an appropriate margin of safety in relation to any uncertainties involved (generally 10x for inter-species and 10x for intra-species variability are employed for extrapolating animal observations to the human situation). The adequacy of the testing procedures for different life stages, or sensitive sub-groups, depending on the intended uses of the materials is also considered. The risk characterisation takes into account the probable extent, nature and duration of the exposure. Guidance values, such as an Acceptable Daily Intake (ADI) for humans might be developed against which expected human exposure from the food applications is then assessed. If the projected exposure exceeds the guidance values, risk management decisions may lead to, for example, restrictions in use levels and/or food categories.
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in the spectral range of the Cimel sun photometers that are used in the AERONET project. This approach allowed us to compare the results obtained by the GRASP-AOD inversion with the standard AERONET inversion. Consequently, the simulation tests proposed in Sect. 3 are done using the wave- lengths in the AERONET network, and the main analysis with real measurements in Sect. 4 corresponds to AERONET data. However, we emphasise that the code is not restricted to AERONET measurements, and some example applica- tions of the code to moon-photometer data are also shown in Sect. 4. Finally we present some retrievals from data ob- tained at different heights during the ChArMEx campaign (Mallet et al., 2016) with the new airborne sun-tracking pho- tometer PLASMA (Karol et al., 2013) fully designed at the LOA (Laboratoire d’Optique Atmosphérique, University of Lille).
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Metal complexes of manganese (II) and cobalt (II) have been synthesized with active hypoglycemic agent (glimepiride), an oral antidiabetic drug. The elemental analyses of the ligand as well as metal complexes indicate that complexes having 2:1 stoichiometry of the type (C 24 H 34 N 4 O 5 S) 2 M.2H 2 O, where M= Mn(II) and Co(II). The complexes have been characterized by IR spectra, electronic spectral and molar conductance data. Infrared spectral studies confirm the co-ordination of sulphonyl oxygen on one side and enolic oxygen attached from other side with the metal ion. On the basis of electronic spectral values the complexes are proposed to have octahedral geometry. The molar conductivity also reveals that the complexes are non-ionic in nature.
not considered here as it is believed that spectral properties alone, if shown suﬃcient, will provide a robust method for cleanness measurement. The paper shows that a multispec- tral vision technique shows good promise to solve the dis- crimination problem and shows how feature extraction from clean and nonclean surfaces can e ﬀ ectively be used to char- acterise, with high probability, areas of a surface that need intensive cleaning. The paper shows how statistical classifi- cation methods can be adopted to this application and used with promising results. The remainder of this paper is organ- ised as follows.
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