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A novel chemiluminescence immunoassay (CLIA) of Bisphenol A (BPA) with the acridinium ester of NSP-SA-NHS-labeled has been developed. In this study, BVA and NSP-SA-NHS had been coupled with BSA, the UV spectrum results indicated the conjugates which were successfully synthesized. Basing on these luminescence data the inhibition curve of BPA was established, then the linear arrang of the curve was between 0.4 ng/ml and 5 ng/ml, the 50% inhibitory concentration (IC50) was 2.3ng/ml, the lowest limit of detection was 0.1ng/ml, which showed it’s an efficient and highly sensitive method.

Objective To investigate whether sunscreens provide optimal protection by exhibiting a uniform spectral absorption profile throughout the ultraviolet spectrum or by having a spectral profile in which absorption in the UVB waveband is greater than in the UVA region. Methods A sunscreen with a flat spectral absorption profile was compared with one of the same SPF in which the SPF to UVA protection was in the ratio of 3 : 1 in terms of protecting against erythema and chronic effects with different action spectra, as well as the total UV burden to the skin. Results A sunscreen with spectral profile in which absorption in the UVB waveband is greater than in the UVA region confers no benefit in terms of erythema (and endpoints with similar action spectra) than a sunscreen with the same SPF that exhibits uniform absorption at all wavelengths throughout the UV spectrum. More importantly, the ‘3 : 1 profile’ offers inferior protection when endpoints with other action spectra are considered, as well as resulting in a total UV burden to the skin that is about 5 times higher than sunscreen products showing a flat spectral absorption profile. Conclusion It may be tempting to believe that it is beneficial to increase the absorption of sunscreens in the UVB region relative to the UVA to reflect the fact that skin damage is associated more with UVB than UVA exposure. However, this belief is a fallacy and consumers are best served with sunscreens in which the spectral protection profile is uniform at all wavelengths throughout the UV spectrum.

An experimental and theoretical study of the UV spectrum of CT was carried out and the vibrationally resolved HOMO→LUMO transition is presented for the first time. The fluorescence spectrum has also been recorded. Furthermore, preparative photolysis in acetonitrile allowed a detailed study of the photoproducts formed with recognition of different isomers. In the presence of oxygen only the first reductive dechlorination-decyanation occurred, while in its absence a successive dechlorination-decyanation takes place. Fil: Cooke, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Oviedo, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Peláez, Walter José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Argüello, Gustavo Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina

Appearing in the early 1980s, at a time when UVA was considered as relatively safe, the tanning industry has substantially developed in occidental countries, especially in Northern European countries. In Europe, the erythemally-weighted irradiance of a modern sunbed should not exceed 0.3 W/m2, equivalent to an UV index of 12, i.e. to a tropical midday sun, but increased in recent years, the UV spectrum emitted by sunbeds had evolved towards higher UVA irradiance and solariums UV had become even less similar to natural sun.

The sharp-line spectrum of the Bp star HR 6000 has peculiarities that distinguish it from those of the HgMn stars with which it is sometimes associated. The position of the star close to the center of the Lupus 3 molecular cloud, whose estimated age is on the order of 9.1 +/- 2.1 Myr, has lead to the hypothesis that the anomalous peculiarities of HR 6000 can be explained by the young age of the star. Observational material from HST provides the opportunity to extend the abundance analysis previously performed for the optical region and clarify the properties of this remarkable peculiar star. Our aim was to obtain the atmospheric abundances for all the elements observed in a broad region from 1250 to 10000 A. An LTE synthetic spectrum was compared with a high-resolution spectrum observed with STIS equipment in the 1250-3040 A interval. The adopted model is an ATLAS12 model already used for the abundance analysis of a high-resolution optical spectrum observed at ESO with UVES. The stellar parameters are Teff=13450K, logg=4.3, and zero microturbulent velocity. Abundances for 28 elements and 7 upper limits were derived from the ultraviolet spectrum. Adding results from previous work, we have now quantitative results for 37 elements, some of which show striking contrasts with those of a broad sample of HgMn stars. The analysis has pointed out ionization anomalies and line-to-line variation in the derived abundances, in particular for silicon. The inferred discrepancies could be explained by non-LTE effects and with the occurrence of diffusion and vertical abundance stratification. In the framework of the last hypothesis, we obtained, by means of trial and error, empirical step functions of abundance versus optical depth log(tau_5000) for carbon, silicon, manganese, and gold, while we failed to find such a function for phosphorous., Accepted by Astronomy & Astrophysics for publication

We report on a study focusing on UV exposure conditions in three different types of chambers used for accelerated ageing of materials. The first chamber is equipped with four 300-W UVA/UVB mercury vapour lamps (Ultra-Vitalux/Osram). The second chamber uses four 40-W UVA fluorescent lamps (QUV-340/Q-Lab). The third chamber is Weather-Ometer Ci3000+ from Atlas with a 4500-W xenon arc lamp. UV irradiance prevailing in each chamber was measured using Bentham DM150 double monochromator spectroradiometer. The results were compared to measurements of solar spectral UV irradiance at Jokioinen, Finland, with a Brewer MkIII double monochromator spectrophotometer. The spectral shapes of the exposing UV radiation in the different chambers were found to notably differ from each other and from the solar UV spectrum. Both spatial inhomogeneities and temporal variability caused by various factors, like the ageing of the lamps, were detected. The effects were found to strongly depend on wavelength of the exposing UV radia...

Ultraviolet cameras are becoming well used, with their applications in botany, dermatology, and recently in photography. In this paper, we develop a novel method of light field estimation from an ultraviolet image. Our UV light field imaging model is obtained by exploiting the radiometry, the optic, and the acquisition geometry. First, we develop an optic simulation model for an UV camera with a thin lens. That model permits to reconstruct a scene image from the correspondent light field. Then, we define a variational formalism that integrates an image of a scene acquired by an UV camera, the depth map of that scene, and the optic simulation model in order to estimate the light field. The experimental results show that it is possible to estimate the light field in the UV spectrum with accuracy.

Structures and electronic excitation energies of the benzophenone–water (Bp–H2O) and benzophenone–methanol (Bp–CH3OH) complexes have been investigated by means of density functional theory calculations. The CAM-B3LYP/6-311++G(d,p) and higher level calculations were carried out for the system. The calculations indicate that free Bp has a nonplanar structure with twist angle of 54.2° for two phenyl rings (referred to as ϕ). In the case of the Bp–H2O system, the twist angle of the phenyl rings and structure of the Bp skeleton were hardly changed by hydration (ϕ = 55.1° for Bp–H2O). However, the excitation energies of Bp were drastically changed by this solvation. The time-dependent density functional calculations show that the n–π* transition (S1 state) is blue-shifted by the solvation, whereas two π–π* transitions (S2 and S3) were red-shifted. The origin of the specific spectral shifts is discussed on the basis of the theoretical results.

Thirty-one samples of 3,4′/4,3′-disubstituted benzylideneanilines (XBAY) with specified UV–Vis absorption maximum wavelength (λmax) were designed and synthesized by applying the equation (Eqn (1)) which was abstracted from the UV–Vis absorption maximum wavelength energy (νmax = 1/λmax) of 4,4′-disubstituted benzylideneanilines. Then, the UV–Vis data (λmax) of the designed compounds were measured in anhydrous ethanol. The predicted UV–Vis data of designed compounds are in agreement with the experimental ones, in which the mean absolute error is 2.9 nm. The results show that Eqn (1) is applicative for the prediction of UV–Vis absorption λmax values of both 4,4′-disubstituted benzylideneanilines and 3,4′/4,3′-disubstituted benzylideneanilines. For a same pair of groups (X and Y), one can at least get four disubstituted benzylideneaniline compounds which have different λmax values. It perhaps provides a convenient method to design an optical material for benzylideneaniline compounds. Copyright © 2014 John Wiley & Sons, Ltd.

Vitamin B12(vB12) was coupled to cBSA by N,N'-Carbonyldiimidazole (CDI) method. The result was confirmed by UV spectrum analysis. It showed that vB12conjugates (vB12-cBSA) were successfully synthesized. By using UV scanning the coupling ratio of artificial antigen was determined which was 6:1. The successful synthesis of vitamin B12artificial antigen is important to establish immunoassay for determining vitamin B12

PCB (Printed Circuit Board) is the backbone of electronics fabrication industry. Tremendous research in PCB fabrication technique has contributed in the reliable and accurate PCB fabrication. There are numerous PCB fabrication techniques available for PCB prototyping. The technique used here to fabricate PCB is UV lithography; the lithography is worldwide accepted technique by semiconductor industry for IC (Integrated Chip) fabrication. Lithography technique uses photosensitive material (Photoresist) coated subject to transfer the required pattern. It is kind of pattern transfer technique with the help of radiation source having wavelength in the range of UV spectrum. The aim of this work is to fabricate low cost PCB fabricating unit for research and educational use. The low cost PCB prototyping equipment is fabricated and tested for its performance. The unit is evaluated, calibrated and automated for its optimum performance to make precise PCBs with better resolution and accuracy. Overviews of Different PCB fabrication techniques for electronics product prototyping are also highlighted.

Most of the spectrometer has the advantages of large volume, inconvenient carrying, slow data reading, long development cycle and high cost. In view of this situation, this paper presents a raspberry based portable spectrum analyzer. The general structure, working principle and data reading principle of the portable ultraviolet spectrum analyzer system based on raspberry faction are introduced in detail. And the raspberry sent a brief introduction, and finally introduced the raspberry pie to the development of the environment configuration, and the use of Python-Qt prepared control software for data read. The final test shows that the system interface is simple and friendly, stable operation, you can quickly read the data from the spectrometer, to meet the actual requirements.

We present absorption properties of colored dissolved organic matter (CDOM) sampled in six different water bodies along extreme altitudinal, latitudinal, and trophic state gradients. Three sites are in Norway: the mesotrophic Lysefjord (LF), Samnangerfjord (SF), and R&oslash, st Coastal Water (RCW), two sites are in China: the oligotrophic Lake Namtso (LN) and the eutrophic Bohai Sea (BS), and one site is in Uganda: the eutrophic Lake Victoria (LV). The site locations ranged from equatorial to subarctic regions, and they included water types from oligotrophic to eutrophic and altitudes from 0 m to 4700 m. The mean CDOM absorption coefficients at 440 nm [ a CDOM ( 440 ) ] and 320 nm [ a CDOM ( 320 ) ] varied in the ranges 0.063&ndash, 0.35 m &minus, 1 and 0.34&ndash, 2.28 m &minus, 1 , respectively, with highest values in LV, Uganda and the lowest in the high-altitude LN, Tibet. The mean spectral slopes S 280 &minus, 500 and S 350 &minus, 500 were found to vary in the ranges of 0.017&ndash, 0.032 nm &minus, 1 and 0.013&ndash, 0.015 nm &minus, 1 , respectively. The highest mean value for S 280 &minus, 500 as well as the lowest mean value for S 350 &minus, 500 were found in LN. Scatter plots of S 280 &minus, 500 versus a CDOM ( 440 ) and a CDOM ( 320 ) values ranges revealed a close connection between RCW, LF, and SF on one side, and BS and LV on the other side. CDOM seems to originate from terrestrial sources in LF, SF, BS, and LV, while RCW is characterized by autochthonous-oceanic CDOM, and LN by autochthonous CDOM. Photobleaching of CDOM is prominent in LN, demonstrated by absorption towards lower wavelengths in the UV spectrum. We conclude that high altitudes, implying high levels of UV radiation and oligotrophic water conditions are most important for making a significant change in CDOM absorption properties.

The present study was undertaken to develop and validate a simple, sensitive, accurate, precise and reproducible UV spectrophotometric method for cefuroxime axetil using methanol as solvent. In this method the simple UV spectrum of cefuroxime axetil in methanol was obtained which exhibits absorption maxima (?max) at 278 nm. The quantitative determination of the drug was carried out at 278 nm and Beer’s law was obeyed in the range of (0.80-3.60) µg/ml. The proposed method was applied to pharmaceutical formulation and percent amount of drug estimated (95.6% and 96%) was found in good agreement with the label claim. The developed method was successfully validated with respect to linearity, specificity, accuracy and precision. The method was shown linear in the mentioned concentrations having line equation y = 0.05x + 0.048 with correlation coefficient of 0.995. The recovery values for cefuroxime axetil ranged from 99.85-100.05. The relative standard deviation of six replicates of assay was less than 2%. The percent relative standard deviations of inter-day precision ranged between 1.45-1.92% and intra-day precision of cefuroxime axetil was 0.96-1.51%. Hence, proposed method was precise, accurate and cost effective. Keywords: UV-Vis spectrophotometer; Method validation; Cefuroxime axetil; Recovery studies. © 2013 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: http://dx.doi.org/10.3329/jsr.v6i1.14879 J. Sci. Res. 6 (1), 133-141 (2013)

Public awareness regarding the risks of prolonged skin exposure to the sun light and more specifically to the UV spectrum part is increased during the last decades. Clothing is the most natural and suitable way of protecting the human body, thus the market interest in clothes that can offer adequate UV protection is growing continuously. Previous research works have revealed the main factors that influence the ability of fabrics to block harmful UV radiation. However, the variability of these factors and the versatility of their combined effect make UV protection factor prediction difficult and hence the design of fabrics with high performance against UV radiation becomes a complicated task. Hopefully, the most critical and predictable among all factors is the fabric structure itself. Expectedly, closer and tighter structures offer higher UV protection. Due to this fact, the majority of previous research concern woven structures which generally are less porous and offer a higher UV protection. However, the possibility to obtain knitted fabrics with adequate UV protection factor is of great interest, since knitted fabrics are more appropriate for sports as well as for casual summer fashion garments. Current literature regarding the UV protection factor of knitted fabrics is very limited and concerns mostly fabrics produced in machines of relative large gauges. In the present work the UV protection factor of various typical weft-knitted structures, produced in a flat knitting machine with 7 gauge and by using grey 100% Organic Cotton yarns, Ne 30/2, 330 TPM (twists per meter) is studied. The yarn has been selected due to the increasing market interest for Organic Cotton products.

An organic–inorganic hybrid phosphotungstate-based CuII–LaIII heterometallic derivative [Cu(dap)2(H2O)][Cu(dap)2]4.5 [La(α-PW11O39)2].4H2O (1) (dap = 1,2-diaminopropane) has been prepared and characterized by elemental analysis, IR spectra, UV spectrum, optical diffuse reflectance spectrum, thermogravimetric analysis, and X-ray crystallography. Complex 1 exhibits a 2-D CuII–LaIII heterometallic sheet architecture with a 4-connected topology established by dimeric [Cu(dap)2(H2O)]2[Cu(dap)2]9[La(α-PW11O39)2]2 building units via [Cu(dap)2]2+ bridges. The optical diffuse reflectance spectrum indicates that 1 possesses the semiconductor characteristic. The thermogravimetric curve of 1 shows two steps of weight loss.

In the present study, augmented antifungal activity of Gandhaka Rasayana in the presence of biosynthesized silver nanopa rticles against selected Candida spp. has been demonstrated. Silver nanoparticles were biologically synthesized from the leaf extract of Couroupita guianensis. The stable silver nanoparticles were characterized by means of UV - Vis spectrophotometer, XRD, TE M, EDX and FTIR; the nanoparticles exhibited maximum absorbance at 415 nm in the UV spectrum. The presence of proteins and functional group was identified by FTIR. TEM micrograph revealed the formation of poly dispersed nanoparticles and the presence of ele mental silver was confirmed by EDS analysis. The antifungal activity of Gandhaka R asayana drastically increased in the presence of lower concentration of bio logically synthesized silver nanoparticles. This would be help ful in reducing the side effects caus ed by the excess use of the drug.

The UV spectrum of octadecyl p-coumarates gives a peak at λmax(MeOH) = 308.6 nm (log e = 4.13). On addition of alkali, the peak undergoes a bathochromic shift to 358.2 nm with a hyperchromic effect. A linear relationship found between the concentration of octadecyl p-coumarates and the hyperchromic effect can be used to quantitatively estimate octadecyl p-coumarates in samples devoid of other compounds exhibiting the similar hyperchromic effect. The method may also be useful for quantitative comparison of total alkyl coumarates in plant samples.

B3LYP, MP2, CCSD(T), and MP4/MP2 in the 6-311G(d, p), 6-311++G(d, p), cc-pVTZ, aug-cc-pVTZ bases used to calculate the transition frequencies of torsional vibration of trans- and cis-isomers of acrolein in the ground electronic state (S 0) are analyzed. It is found that for trans-isomers, all methods of calculation except for B3LYP in the cc-pVTZ basis yield good agreement between the calculated and experimental values. It is noted that for the cis-isomer of acrolein, no method of calculation confirms the experimental value of the frequency of torsional vibration (138 cm−1). It is shown that the calculated and experimental values for obertones at 273.0 cm−1 and other transitions of torsional vibration are different for this isomer in particular. However, it is established that in some calculation methods (B3LYP, MP2), the frequency of the torsional vibration of the cis-isomer coincides with another experimental value of this frequency (166.5 cm−1). It is concluded that in analyzing the vibrational structure of the UV spectrum, the calculated and experimental values of its obertone (331.3 cm−1) coincide, along with its frequency. It is also noted that the frequency of torsional vibration for the cis-isomer (166.5 cm−1) can also be found in other experimental works if we change the allocation of torsional transition 18 1 1 .

Nowadays water pollution is a major problem facing our country, how to detect the water quality anomalies quickly is a major issue which needs to be solved urgently. In this paper, using PCA and cluster analysis methods, the similarities and differences of different water samples are analyzed. Meanwhile, two water samples belonging to the same river can be classified into different clusters due to different pollution degrees. It is promising that detecting the abnormal events based on the ultraviolet spectrum of water is possible. The research and results of this paper provide theoretical support and feasibility roadmap of the technology.

Here, we demonstrate the field applicability of the Ag-TiO2 Schottky diodes for environmental UV level measurements. The device is visible-blind and it is shown that its maximum sensitivity coincides the environmental UV spectrum (UV-A). These features, along with its low voltage and biasing insensitivity of its operation, simplify the electronic circuit required for the fabrication of a hand-held UV monitoring system.

A new accelerated weathering protocol has been developed which closely replicates the performance of automotive and aerospace coating systems exposed in South Florida. IR spectroscopy was used to verify that the chemical composition changes that occurred during accelerated weathering in devices with a glass filter that produced a high fidelity reproduction of sunlight’s UV spectrum matched those that occurred during natural weathering. Gravimetric water absorption measurements were used to tune the volume of water absorption during accelerated weathering to match that which occurred during natural weathering in South Florida. The frequency of water exposure was then scaled to the appropriate UV dose. A variety of coating systems were used to verify the correlation between the physical failures observed in the accelerated weathering protocol and natural weathering in South Florida. The new accelerated weathering protocol correctly reproduced gloss loss, delamination, cracking, blistering, and good performance in a variety of diverse coating systems. For automotive basecoat/clearcoat paint systems, the new weathering protocol shows significant acceleration over both Florida and previous accelerated weathering tests. For monocoat aerospace systems, the new weathering protocol showed less acceleration than for automotive coatings, but was still an improvement over previous accelerated tests and was faster than Florida exposure.

N-butyl Pyridine Nitrate ionic liquid is prepared by the double decomposition reaction of BPC and NaNO3. The ionic liquid at room temperature used in the experiment has a significant absorption determined by UV spectrum within the range of 200-400nm, the maximum absorption wavelength of BP-NO3ionic liquid is 256nm. The standard working curve of BP-NO3ionic liquid is y= 0.06848x + 0.04427(R=0.99913). The recovery rate of BP-NO3ionic liquid which is between 100.2% and 102.4%, is measured by standard addition method in water.

N-butyl Pyridine Nitrate ionic liquid is prepared by the double decomposition reaction of BPC and NaNO3. The ionic liquid at room temperature used in the experiment has a significant absorption determined by UV spectrum within the range of 200-400nm, the maximum absorption wavelength of BP-NO3 ionic liquid is 259nm. The standard working curve of BP-NO3 ionic liquid is y=0.04555x+0.05604 (R=0.99922). The recovery rate of BP-NO3 ionic liquid which is between 99.8% and 103.4%, is measured by standard addition method in ethanol.

Zn(II)meso-tetra(α,β,α,β-o-pivalamidophenyl)-porphyrin was synthesized as a sensing material. It indicated an excellent film performance and significant optical response ability, which can be used for gas detection, such as: NO2, SO2and NH3.This material was characterized by IR, NMR, and AES, and its Langmuir-Blodgett films properties were also studied by means of UV-Vis-spectroscopy. The results showed that the zinc porphyrin’s UV spectrum and LB films properties occurred a great change compared with protoporphyrin, and it also had a good film forming capability and stability.

The spectrum-integral Talbot lithography (STIL) was introduced into the fabrication of one-dimensional micro gratings using the broad-band UV illumination in this paper. In the process of spectrum-integral Talbot lithography, the self-images and π-phase-shifted images generated by different wave lengths overlap and integrate collectively to enormously extend the continuous depth-of-focus area since a certain distance away from the mask. As a result, the route of STIL proves to be of great potential for periodic frequency-doubling in good contrast without any complex improvement and operation to the traditional proximity lithographic system of UV mask aligner.

Compared to coating on the photosensitive surface of the thinned back-illuminated CCD, the coating on the surface of the front-illuminated (FI) CCD is relatively simple, controllable and cheaper which shows great market value. The ultraviolet (UV) response enhancement technology of the FI CCD is studied based on a spin-coating method. After the fluorescent powder is coated on the photosensitive surface of the CCD, the CCD is assembled in the micro UV spectrometer prototype. The UV responses of the CCD are compared before and after coating. The results indicate that the UV spectrum response of CCD is greatly enhanced at the range of 200∼313 nm after coating. Moreover, the intensity of discrete spectrum is improved but the resolution of the spectrometer is not changed.

Self-doped polyanilines are polyaniline derivatives that the functional groups, such as sulfonic, boronic and carboxylic acid, bound to the polymer backbones. In our studies, we had an experiment about the phosphonic acid as a dopant for polyaniline, and synthesized the self-doped polyaniline bearing phosphonic acid, poly (3-aminophenyl phosphonic acid), in different surrounding solvents. In addition, the self-doped polyaniline bearing phosphonic acid was analyzed it's qualitative and morphology by UV spectrum and scanning electron microscope (SEM).

Based on characteristic UV spectrum of the ene-diyne chromophore, one new polyacetylene glucoside and three known polyacetylene glucosides have been isolated from the EtOH extract of Coreopsis tinctoria. Their chemical structures were determined by detailed spectroscopic analysis and by comparison with literature data. Compounds 1-2 were tested for their antiadipogenic effects on 3T3-L1 adipocytes, and both of them reduced lipid accumulation dose-dependently in 3T3-L1 adipocytes.

This work presents the analysis of the deterministic part of human colour perception at the computational, algorithmic and implementation levels. At the computational and algorithmic levels, we invoke the theory of Fuzzy sets. At the implementation level, we present Biologically Inspired Photochromic Fuzzy Logic (BIPFUL) systems that are useful to discriminate between the three regions of the UV spectrum (UV-A, UV-B and UV-C). Such BIPFUL systems have been devised by imitation of the human photosensitive system on retina. After transforming the absorption spectra, originated by the BIPFUL systems under UV-A, UV-B and UV-C, in chromaticity coordinates and vectors in CIE L*a*b* spaces, we have compared their performances through the determination of two parameters: The Colourability and the Eucledian distance. Finally, the guiding principles for the design of new BIPFUL systems are outlined.

An ultraviolet (UV) absorption method has a difficulty to analyze ClO2(aq) in solutions containing various chlorine species because UV spectrum of ClO2(aq) overlaps with other chlorine-containing species. This study has proposed the deconvolution method of UV spectrum to analyze ClO2(aq) concentration quantitatively in solution containing various chlorine species. We compared results obtained from UV deconvolution method with titration method. Good agreement of ClO2(aq) concentration between them has been shown in about 10%. This result informs us that the deconvolution method of UV spectrum could be a feasible for the analysis of ClO2(aq) in solution containing various chlorine species.

An organic–inorganic hybrid paratungstate [enH2]2[Cu(en)2]3[H2W12O42]·6H2O (1) (en = ethylenediamine) has been hydrothermally synthesized by reaction of Na2WO4·2H2O with CuCl2·2H2O in the presence of en and structurally characterized by elemental analyses, IR spectroscopy, UV spectrum, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and X-ray single-crystal diffraction. It is worth pointing out that 1 exhibits the 6-connected 3-D framework with the long topological (O'Keeffe) vertex symbol 4·4·64·4·4·4·4·64·4·4·4·64·4·4·4 for the [Cu(en)2]3[H2W12O42]4 − node, which gives the short vertex (Schlafli) symbol of 41263. To the best of our knowledge, such 6-connected 3-D open-framework constructed from paratungstate clusters is for the first time observed in polyoxometalate chemistry.

Background: Repaglinide is a miglitinide class of antidiabetic drug used for the treatment of type 2 diabetes mellitus. A fast and reliable method for the determination of repaglinide was highly desirable to support formulation screening and quality control. Objective: UV spectrophotometric and reversed-phase high performance liquid chromatography (RP-HPLC) methods were developed for determination of repaglinide in the tablet dosage form. Materials and Methods: The UV spectrum recorded between 200 400 nm using methanol as solvent and the wavelength 241 nm was selected for the determination of repaglinide. RP-HPLC analysis was carried out using Agilent TC-C18 (2) column and mobile phase composed of methanol and water (80:20 v/v, pH adjusted to 3.5 with orthophosphoric acid) at a flow rate of 1.0 ml/min. Parameters such as linearity, precision, accuracy, recovery, specificity and ruggedness are studied as reported in the International Conference on Harmonization (ICH) guidelines. Results: The developed methods illustrated excellent linearity (r2 > 0.999) in the concentration range of 5-30 μg/ml and 5-50 μg/ml for UV spectrophotometric and HPLC methods, respectively. Precision (%R.S.D < 1.50) and mean recoveries were found in the range of 99.63-100.45% for UV spectrophotometric method and 99.71-100.25% for HPLC method which shows accuracy of the methods. Conclusion: The developed methods were found to be reliable, simple, fast, accurate and successfully used for the quality control of repaglinide as a bulk drug and in pharmaceutical formulations.

By employing thiamine (vitamin B1) as the catalyst, the synthesis of furoin from furfuraldeyde has been developed. Furoin is oxidized to furil by Cu(OAc)2-NH4NO3 as an oxidant. The reaction condition is optimized and the reaction mechanism is discussed in this paper. The synthesized furoin and furil are characterized by means of Mass, IR and UV spectrum.

The objective of this study was to determine the regiospecificity of the important uridine diphosphate glucuronosyltransferase (UGT) isoforms responsible for the glucuronidation of flavones and flavonols. We systematically studied the glucuronidation of 13 flavonoids (7 flavones and 6 flavonols, with hydroxyl group at C-3, C-4’, C-5, and/or C-7 positions in flavonoid structure) at a substrate concentration of 10μM by 8 recombinant human UGT isoforms mainly responsible for metabolism of flavonoids, UGT 1A1, 1A3, 1A6, 1A7, 1A8, 1A9, 1A10 and 2B7. At 10μM substrate concentration, different UGT isoforms gave different regiospecific glucuronidation patterns. UGT1A1 equally glucuronidated 3-O (glucuronic acid substituted at C-3 hydroxyl group), 7-O and 4’-O, whereas UGT1A8 and 1A9 preferably glucuronidated only 3-O and 7-O positions. UGT1A1 usually showed no regiospecificity for glucuronidating any position, whereas, UGT1A8 and UGT1A9 showed dominant, moderate or weak regiospecificity for 3-O or 7-O position, depending on the structure of the compound. UGT1A3 showed dominant regiospecificity for 7-O position, whereas 1A7 showed dominant regiospecificity for 3-O position. We also showed that the glucuronidation rates of 3-O and 7-O positions in flavones and flavonols were affected by the addition of multiple hydroxyl groups at different positions as well as by the substrate concentrations (2.5, 10 and 35μM). In conclusion, regiospecific glucuronidation of flavonols was isoform- and concentration- dependent, whereas flavones were dominantly glucuronidated at 7-O position by most UGT isoforms. We also concluded that UGT1A3 and UGT1A7 showed dominant regiospecificity for only 7-O and 3-O position, respectively. UGT1A8 and UGT1A9 showed moderate or weak preference on glucuronidating position 3-O over 7-O position, whereas other UGT isoforms did not prefer glucuronidating any particular positions.

Because of their photo-optical distinctiveness and biocompatibility, gold nanoparticles have proven to be powerful tools in various nanomedical applications. In this article, we discuss the advantage of gold nanoparticles in image diagnostic application of melanoma. It has demonstrated the potential role of gold nanoparticles in the study of tumour tissue architecture and the utility of gold nanoparticles in the hystopathological exam of B16 melanoma with the benefit of fluorescence emission of gold nanoparticles in UV spectrum. The optical properties of colloidal gold nanoparticles allow spectroscopic detection and identification of melanoma cells. The method proposed is easy, inexpensive and reliable for hystopathological analysis of melanoma. The fluorescence images in the cryosections of tissues depicted a strong luminescence property of gold nanoparticles uptaken in melanoma, results that confirm the role of the gold nanoparticles in biological labelling and imaging applications. To emphasize the AuNPs influence over the biological tissues, a study of the chemical bonds configuration was performed using Raman spectrometry.

The UV spectrum of the cross-conjugated compound 2,3-diphenyl-1,3-butadiene, which can occur in both an s-gauche and s-trans conformation, is reported. The spectrum is interpreted with the use of ZINDO/S calculations and compared to the spectrum of styrene. In both conformations the difference in electronic transition energy with styrene is negligible, despite a shift in HOMO and LUMO energy. This is the consequence of the decrease of Coulomb and exchange energies by which extension of the π-system is accompanied. As such, the UV spectrum of 2,3-diphenylbutadiene, as compared to that of styrene, does not reflect extension of the π-system.

A new chrome free tanning system of rare earth (RE)-THPS has been developed in this study. It has been proved by UV spectrum that THPS and RE (CeCl3) can coordinate under certain conditions. The influence of CeCl3and THPS’s ratio, pH and ligands on the shrinkage temperature (Ts) was studied. Higher Ts was obtained while the tannage was processed in the sequence of THPS followed by CeCl3. The alkaline pH should be controlled between 5.5 and 6.0 to give ideal tanning effect. It was also found that employing of 0.5% tartaric acid in this combination tanning system can give high Ts of 89°C.

The photochemistry and complexation with alkaline-earth metal cations of two crown-containing naphthopyrans and their crownless analogues are reported. Two types of photoreactions occur in the system, namely, the reversible formation of the open form, which is responsible for the photochromism of these compounds, and the geometric isomerization of the closed form. The photochromic properties (UV spectrum and lifetime) of the naphthopyrans do not change upon complexation with metal cations. This is explained by the specific features of the structure of the open form and by the kinetic parameters of the processes.

Measurements of the diffuse reflection coefficients of organic and inorganic materials and media in solid, granular and liquid forms were made in the UV field of 230–400 nm. A single channel spectrometer with an integrating sphere was used. Relation between diffuse reflection coefficients and the structure and composition of the samples is discussed. These data allow us to estimate the prospect of machine vision systems application for the UV range in such areas as biology, geology, remote control of materials and media.

In this article, we describe general trends to be expected at short times when an excess electron is generated or injected in different room-temperature ionic liquids (RTILs). Perhaps surprisingly, the excess electron does not localize systematically on the positively charged cations. Rather, the excess charge localization pattern is determined by the cation and anion HOMO/LUMO gaps and, more importantly, by their relative LUMO alignments. As revealed by experiments, the short-time (ps/ns) transient UV spectrum of excess electrons in RTILs is often characterized by two bands, a broad band at low energies (above 1000 nm) and another weaker band at higher energies (around 400 nm). Our calculations show that the dry or presolvated electron spectrum (fs) also has two similar features. The broad band at low energies is due to transitions between electronic states with similar character on ions of the same class but in different locations of the liquid. The lower-intensity band at higher energies is due to transitions in which the electron is promoted to electronic states of different character, in some cases on counterions. Depending on the chemical nature of the RTIL, and especially on the anions, excess electrons can localize on cations or anions. Our findings hint at possible design strategies for controlling electron localization, where electron transfer or transport across species can be facilitated or blocked depending on the alignment of the electronic levels of the individual species.

The performance of Time-Dependent Density Functional Theory (TD-DFT) in the prediction of the low-energy region of the electronic absorption spectrum of a model aromatic endoperoxide (anthracene-9,10-endoperoxide, APO) has been assessed against accurate MS-CASPT2//CASSCF transition energies and oscillator strengths for comparison. This survey includes functionals belonging to one of the four main categories: GGA, meta-GGA, Global Hybrids and Range-Separated Hybrids. Our results show that the absorption spectrum of APO is strongly functional-dependent. In general, GGA and meta-GGA functionals poorly describe charge transfer (CT) excitations but reasonably reproduce local π * σ * and ππ * transitions. The incorporation of a fixed or increasing fraction of exact exchange along interelectronic distances improves the description of CT states. A functional, which combines a 32% of exact exchange, 72% of non-local B88 exchange and LYP correlation is found to be the best choice, with an average error of 0.75 eV. Despite this relatively large error, this functional is able to reproduce correctly the order of the lowest π * σ * and ππ * excited states of the UV spectrum of APO.

An inexpensive and simple approach using ultraviolet-spectroscopy to distinguish vinegar samples was developed. Vinegar samples were diluted with distilled water(water/vinegar was 6/1, v/v), then distilled with rotary evaporator at 45°C. The distilled liquid was introduced into the UV-Vis 2550 spectrophotometer to scan the UV spectrum from 245 nm to 330 nm, distilled water was used as reference solution. Once spectra were collected, principal components analysis (PCA) and artificial neural network (ANN) were employed for the exploratory analysis and the development of classification models, respectively. The criteria for discrimination were various raw materials and the different fermentation process of vinegars. The correct rate of the classification according to the production process was more than 90% and it was 100% according to the raw materials. The ANN model also could be used to class vinegar samples according to the raw materials, the correct rate was 80.95% in this research.