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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124593, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-38865884

RESUMEN

Cohumulone and colupulone are representatives of α- and ß-acids, respectively. These compounds are important antimicrobial hop (Humulus lupulus) constituents, where cohumulone is an important source of the bitter taste of beer. In this study, we examined the pH dependence of UV/Vis spectra of both compounds while CD spectra of cohumulone were also measured at various wavelengths. This facilitated the examination of the protolytic equilibrium of both compounds, where the second pKa value of cohumulone was determined for the first time. Additionally, comparing experimental spectra with spectra calculated using time-dependent density functional theory (TD-DFT) enabled the determination of the most likely deprotonation positions and corresponding species most likely present in the aqueous solution at various pH values. Last but not least, comparing calculated and experimental CD spectra of cohumulone facilitated the determination of the absolute stereoconfiguration of cohumulone.

2.
Int J Mol Sci ; 25(11)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38891775

RESUMEN

One useful technique for increasing the efficiency of organic dye-sensitized solar cells (DSSCs) is to extend the π-conjugated bridges between the donor (D) and the acceptor (A) units. The present study used the DFT and TD-DFT techniques to investigate the effect of lengthening the polyene bridge between the donor N, N-dimethyl-anilino and the acceptor dicyanovinyl. The results of the calculated key properties were not all in line with expectations. Planar structure was associated with increasing the π-conjugation linker, implying efficient electron transfer from the donor to the acceptor. A smaller energy gap, greater oscillator strength values, and red-shifted electronic absorption were also observed when the number of polyene units was increased. However, some results indicated that the potential of the stated dyes to operate as effective dye-sensitized solar cells is limited when the polyene bridge is extended. Increasing the polyene units causes the HOMO level to rise until it exceeds the redox potential of the electrolyte, which delays regeneration and impedes the electron transport cycle from being completed. As the number of conjugated units increases, the terminal lobes of HOMO and LUMO continue to shrink, which affects the ease of intramolecular charge transfer within the dyes. Smaller polyene chain lengths yielded the most favorable results when evaluating the efficiency of electron injection and regeneration. This means that the charge transfer mechanism between the conduction band of the semiconductor and the electrolyte is not improved by extending the polyene bridge. The open circuit voltage (VOC) was reduced from 1.23 to 0.70 V. Similarly, the excited-state duration (τ) decreased from 1.71 to 1.23 ns as the number of polyene units increased from n = 1 to n = 10. These findings are incompatible with the power conversion efficiency requirements of DSSCs. Therefore, the elongation of the polyene bridge in such D-π-A configurations rules out its application in solar cell devices.


Asunto(s)
Colorantes , Polienos , Energía Solar , Polienos/química , Colorantes/química , Teoría Funcional de la Densidad , Compuestos de Anilina/química , Transporte de Electrón
3.
J Comput Chem ; 45(16): 1404-1418, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38436207

RESUMEN

Terthiophene derivatives attract interest due to their prospective applications in optoelectronic or sensor devices. Due to their nontoxicity they can be considered as suitable candidates in biological applications. Supramolecular organization of the matter is one of the most interesting topics in contemporary materials science. Amphiphilic chromophores based on substituted terthiophenes are capable of self-assembly into supramolecular architectures. In this work, we aim at simulation of the spectral properties of terthiophene with oligo(ethylene oxide) substituents by the methods of quantum chemistry and molecular dynamics (MD). The potential energy surface (PES) of this molecule was determined by the methods of density functional theory (DFT) for the ground state and time-dependent density-functional theory (TD-DFT) for the excited state. MD simulations in water than revealed the most frequented molecular conformations in both these states. Absorption and fluorescence spectra were determined for all these conformations, including the surrounding water molecules, using TD-DFT and averaged over the conformation space to obtain the final absorption and fluorescence spectrum. The calculated spectra were compared with their experimental counterparts and the differences were discussed in context of the supramolecular structure revealed by confocal microscopy. In spite of its simplicity, this approach provides a satisfactory approximation of absorption and fluorescent spectra of these molecules obtained by computational methods.

4.
Food Chem X ; 21: 101192, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38389575

RESUMEN

This study utilized a colorimeter to determine the color values of 23 beauty tea (BT) samples, the color and the taste characteristics were also quantitatively described through ultraviolet-visible (UV-Vis) spectroscopy and taste equivalent quantification. Furthermore, metabolomic analysis was conducted by using ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS). Correlation analysis was employed to preliminarily identify the compounds that contribute to the color and taste of BT infusion. Finally, the contributing compounds were further determined through verification experiment. The results showed that within a certain range, as the color of BT infusion deepened, the taste became stronger, more bitter and astringent, while on the contrary, it became sweeter and mellower. Theaflavins, kaempferol, astragalin, and 5-p-coumaroylquinic acid influenced both the color and taste of the BT infusion. Gallic acid was also determined as a contributor to the color. This study provides new insights into research on tea quality in infusion color and taste aspects.

5.
Anal Sci ; 40(3): 489-499, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38165524

RESUMEN

In our study, we present an innovative method for the analysis and real-time monitoring of peracetic acid (PAA) formation within the near-UV/Vis (visible) wavelength region. PAA's absorption spectrum, influenced by its presence in a complex quaternary equilibrium mixture with hydrogen peroxide (H2O2), acetic acid, and water, lacks discernible peaks. This inherent complexity challenges conventional analytical techniques like Beer's law, which rely on absorption intensity as a foundation. To address this challenge, we introduce a novel approach that centers on the analysis of blue shifts in absorption wavelengths, particularly at an absorbance of 0.8 a.u. This method significantly enhances the precision of calibration curves for both diluted PAA and H2O2, unveiling an exponential correlation between wavelength and the logarithm of concentration for both components. Significantly, our approach allows for real-time and accurate measurements, especially during the dynamic PAA formation reaction. Our results exhibit excellent agreement with data obtained from Fourier-transform infrared (FT-IR) spectroscopy, validating the reliability of our method. It's noteworthy that under stable PAA concentration conditions (after 12 h of solution interaction), both traditional absorption method and our approach closely align with the FT-IR method. However, in dynamic scenarios (0-12 h), the absorption method exhibits higher error rates compared to our approach. Additionally, the increased concentration of a catalyst, sulfuric acid (H2SO4), significantly reduces the errors in both methods, a finding that warrants further exploration. In summary, our study not only advances our understanding of PAA and its spectral behavior but also introduces innovative and precise methods for determining PAA concentration in complex solutions. These advancements hold the potential to revolutionize the field of chemical analysis and spectroscopy.

6.
Environ Technol ; : 1-9, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37183424

RESUMEN

We propose in this study to develop a rapid, reliable, and non-culture method to detect and estimate bacteriophage (phage) titre as an alternative to the routine use of the double agar overlay assay (DLA). The present method is based on the analysis of nanoparticle (NPs) dispersion/aggregation dynamic in interaction with the phage. Titanium dioxide nanoparticles (TiO2-NPs) were used as nanosensors to detect and monitor virions' titres in aqueous samples. Dispersion stability of TiO2-NPs in aqueous suspension was investigated using a UV-Visible spectrophotometer. The comparison of NP spectral profiles with and without phage elucidated the impact of phage's titre on NP dispersion/aggregation behaviour in an aqueous solution. Indeed, the increase of nanoparticle dispersion stability is correlated with the increase of phage titre. Thus, based on this result, the phage was considered as a bio-dispersant agent. The determination of area under spectral profiles limiting the UV region [200-400 nm] was allowed to quantify, and compare the NPs bio-dispersion rate, in relation with added phage at different titres. In this study, this method was applied to monitor the phage amplification cycle for the detection of bacteria in viable but non-culturable (VBNC) state after water treatment by photocatalysis. The analysis of NP bio-dispersion rate shows an increase of TiO2-NP dispersion stability correlated with an increase of free phage titration, mainly after the entry of target bacteria in VBNC state underestimated using a conventional method. Thus, this method could allow the establishment of new recommendations of wastewater treatment and assessment.

7.
Pharm Nanotechnol ; 11(3): 303-314, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36744688

RESUMEN

INTRODUCTION: Recent advancements in biomedicine have revolutionized nanomedicine as a therapeutic moderator in the management of both infectious and noninfectious diseases. PURPOSE: In the current study we demonstrated biosynthesis of gold nanoparticles using aqueous leaf extract of Lasiosiphon eriocephalus as a capping and reducing agent and evaluation of their antioxidant, antibacterial, and anticancer properties. METHODS: The biosynthesized LE-AuNPs were characterized by UV-Vis spectrophotometry, SEM, TEM, XRD, FTIR, DLS, and Zeta potential analysis. The antibacterial activity was checked by a minimum inhibitory concentration assay. The anticancer potential of biogenic LE-AuNPs was checked by cytotoxicity and genotoxicity assay against HeLa and HCT-15 cells. RESULTS: The characteristic surface plasmon resonance peak of the colloidal solution at 538 nm by UV-Vis spectrum confirmed the formation of LE-AuNPs in the solution. The SEM, TEM, and XRD revealed 20-60 sized hexagonal and crystalline LE-AuNPs. The LE-AuNPs displayed significant inhibition potential against DPPH and ABTS radicals in vitro. The LE-AuNPs demonstrated significant antibacterial potential. The results of cytotoxicity interpreted that biogenic gold nanoparticles exhibited strong dose and time-dependent cytotoxicity effect against selected cancer cell lines where IC50 of LE-AuNPs required to inhibit the growth of HeLa cells after 24 h and 48 h exposure were 5.65± 0.69 µg/mL and 4.37±0.23 µg/mL respectively and that of HCT- 15 cells was 6.46 ± 0.69 µg/mL and 5.27 ± 0.34 µg/mL, 24h and 48h post-exposure respectively. CONCLUSIONS: Findings from this study revealed that gold nanoparticles synthesized using L. eriocephalus, showed remarkable antioxidant, antimicrobial, and extensive cytotoxicity and genotoxicity activities.


Asunto(s)
Oro , Nanopartículas del Metal , Humanos , Oro/química , Células HeLa , Antioxidantes/farmacología , Antioxidantes/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 287(Pt 2): 122082, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36370632

RESUMEN

Gold nanostructures are used as catalysts in heterogeneous catalytic processes and have intrigued chemists and materials scientists. Isotropic spherical gold nanoparticles (AuNPs) are ideal for catalysis due to their simple preparation process, controllable surface-active site, tunable size, and composition-dependent catalytic activity. In this study, spherical AuNPs with different size, composition, and surface capping agents have been prepared, and their catalytic activity in reduction of 4-nitrophenol (4-NP) is evaluated. The catalytic activity of AuNPs decreases as their size increases. Meanwhile, the catalytic activity of AuNPs with tartrate as the reducing agent show no evident changes because of containing anisotropic AuNPs. Moreover, silver not only improves monodisperse and spherical AuNPs, but also increases the catalytic activity of small AuNPs. Since the molecular structures of tartrate and citrate are similar, there is no remarkable difference in the catalytic activity of AuNPs using tartrate and citrate as capping agents. These results demonstrate the influence of size, composition, and surface capping on the catalytic activity of AuNPs. Overall, this study facilitates the applicability of gold-based catalyst and AuNPs in plasmonics, nanophotonics, biomedical photonics, and photocatalysis.


Asunto(s)
Oro , Nanopartículas del Metal , Oro/química , Tartratos , Nanopartículas del Metal/química , Catálisis , Citratos , Tamaño de la Partícula
9.
Asian J Pharm Sci ; 17(4): 544-556, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36105314

RESUMEN

Amphotericin B (AmB) is an amphiphilic drug commonly formulated in liposomes and administered intravenously to treat systemic fungal infections. Recent studies on the liposomal drug product have shed light on the AmB aggregation status in the bilayer, which heat treatment (curing) modifies. Although toxicity was found related to aggregation status - loose aggregates significantly more toxic than tight aggregates - the precise mechanism linking aggregation and toxicity was not well understood. This study directly measured drug release rate from various AmB liposomal preparations made with modified curing protocols to evaluate correlations among drug aggregation state, drug release, and in vitro toxicity. UV-Vis spectroscopy of these products detected unique curing-induced changes in the UV spectral features: a ∼25 nm blue-shift of the main absorption peak (λmax) in aqueous buffer and a decrease in the OD346/OD322 ratio upon thermal curing, reflecting tighter aggregation. In vitro release testing (IVRT) data showed, by applying and fitting first-order release kinetic models for one or two pools, that curing impacts two significant changes: a 3-5-fold drop in the overall drug release rate and a ten-fold decrease in the ratio between the loosely aggregated and the tightly aggregated, more thermodynamically stable drug pool. The kinetic data thus corroborated the trend independently deduced from the UV-Vis spectral data. The in vitro toxicity assay indicated a decreased toxicity with curing, as shown by the significantly increased concentration, causing half-maximal potassium release (TC50). The data suggest that the release of AmB requires dissociation of the tight complexes within the bilayer and that the reduced toxicity relates to this slower rate of dissociation. This study demonstrates the relationship between AmB aggregation status within the lipid bilayer and drug release (directly measured rate constants), providing a mechanistic link between aggregation status and in vitro toxicity in the liposomal formulations.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 279: 121413, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35660652

RESUMEN

As one of the important factors in chemical production, catalyst content directly affects the process of reaction and the quality of products. The quantitative analysis of trace catalyst in homogeneous reaction system is still faced with great challenges. In this work, a simple and effective approach to the rapid determination of trace homogeneous catalyst (THC) was proposed based on UV-vis spectrophotometry. Wavelet transform and Tchebichef curve moment methods were combined with gray wolf algorithm to extract the feature information from the original UV-vis spectra of samples. Then the partial least-squares model was established. The predictive correlation coefficient (Rp2) was 0.9842, and the limit of quantification was 0.07 ‰. The intra-day and inter-day precision were 3.97 % and 4.36 %, respectively. The spiked recoveries of three different concentrations in actual samples were between 97.6 and 101.9 %. The results indicated that the obtained model was satisfactory and could be used in practical measurement. Compared with the conventional modeling methods, the proposed approach was more accurate and reliable, which provided a feasible new pathway for enterprise product quality control.


Asunto(s)
Algoritmos , Análisis de Ondículas , Análisis de los Mínimos Cuadrados , Control de Calidad
11.
Nanomaterials (Basel) ; 12(10)2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35630999

RESUMEN

Nowadays, the incorporation of nanoparticles into thermal fluids has become one of the most suitable strategies for developing high-performance fluids. An unconventional improvement of thermo-physical properties was observed with the addition of 1% wt. of nanoparticles in different types of fluids, such as molten salts, allowing for the design of more thermally efficient systems using nanofluids. Despite this, there is a lack of knowledge about the effect that nanoparticles produce on the thermal stability and the decomposition kinetics of the base fluid. The present study performs IR- and UV-vis spectroscopy along with thermogravimetric analysis (TGA) of pure nitrate and nitrate based nanofluids with the presence of SiO2 and Al2O3 nanoparticles (1% wt.). The results obtained support that nanoparticles accelerate the nitrate to nitrite decomposition at temperatures below 500 °C (up to 4%), thus confirming the catalytic role of nanoparticles in nanofluids.

12.
Molecules ; 27(7)2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35408638

RESUMEN

In 1996, we reported that silyl groups of 9,10-disilylanthracenes significantly affect the UV/Vis and fluorescence spectra. Although the results indicate that the silyl groups have strong electronic effects on anthracene, the details of the mechanisms responsible for this have not yet been clarified. This article describes the analysis of the UV/Vis and fluorescence spectra of 9,10-bis(diisopropylsilyl)anthracene by theoretical calculations. This study reveals that π conjugation of anthracene is extended by cooperation of σ-π and σ*-π* conjugation between the silyl groups and anthracene. This effect increases the transition moment of the π-π* transition of anthracene. As a result, the molecular extinction coefficient of the 1La band and the fluorescence quantum yield are increased.


Asunto(s)
Fluorescencia , Fenómenos Químicos
13.
Water Res ; 198: 117153, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33940502

RESUMEN

In this work, UV-vis absorption spectrum of the membrane integrity analysis based on slopes of log-transformed absorbance spectra, differential absorbance spectroscopy (DAS), and absorption coefficient α(254) were studied at different number of breakage fibers and filtration times. Moreover, we analyze the influence of Fe2+ and Ca2+concentration on UV spectrum detection results. Cluster analysis and the change ratio Rs were used to determine the dissolved organic matter (DOM) leakage stages. As a result, the correlation coefficient between slope280-350 value and the number of breakage fibers is 0.901. Seven gaussian bands were successfully model from the DAS, and A4 (312 nm), A5 (339 nm), A6 (367 nm) were chosen to indicate the extent of breakage fiber. Peak 4(A4) is minimally affected by ions concentration. The α(254) could be used as a good indicator for detecting industrial wastewater treatment process which correlation coefficient between the number of breakage fibers is 0.955. The DOM leakage process was divided into three stages which were bulk leakage stage, development stage and stabilization stage. The UV-vis absorption spectrum can effectively detect the membrane integrity more sensitive than particle counter and three analyse methods are suitable for different substance in feed water.


Asunto(s)
Purificación del Agua , Reactores Biológicos , Filtración , Iones
14.
Molecules ; 26(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33804233

RESUMEN

π-Electron systems of silicon have attracted attention because of their narrow HOMO-LUMO gap and high reactivity, but the structural diversity remains limited. Herein, new dialkylboryl-substituted disilenes were synthesized by the selective desilylation-borylation of the corresponding trimethylsilyl-substituted disilenes. The dialkylboryl-substituted disilenes were fully characterized by a combination of NMR spectroscopy, MS spectrometry, single-crystal X-ray diffraction analysis, and theoretical calculations. The longest-wavelength absorption bands of boryldisilenes were bathochromically shifted compared to the corresponding silyl-substituted disilenes, indicating a substantial conjugation between π(Si=Si) and vacant 2p(B) orbitals. In the presence of 4-(dimethylamino)pyridine (DMAP), the dialkylboryl groups in the boryl-substituted disilenes were easily converted to trimethylsilyl groups, suggesting the dialkylboryl-substituted disilenes in the presence of a base serve as the surrogates of disilenyl anions (disilenides).

15.
Huan Jing Ke Xue ; 42(4): 1889-1900, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742824

RESUMEN

Based on excitation emission matrix spectroscopy (EEMs) technology combined with the parallel factor analysis (PARAFAC) and UV-vis spectra, the spectral characteristics and sources of dissolved organic matter (DOM) from a landscape river were analyzed during different periods of the flood season in Suzou. Four fluorescent components were identified using the PARAFAC model, including two humus-like components (C1, C4) and two protein-like components (C2, C3), with a significant correlation coefficient (P<0.01) in C2 and C3/C4 and C3 and C4, respectively. During the early flood season, the total fluorescence intensity of the DOM in the river was relatively higher due to the influence of initial rainwater but reduced significantly towards the middle and late flood season. The fluorescence characteristic parameters indicated that the autochthonous contribution of DOM were substantial during the early stages of the flood season. On the contrary, there were increased levels of DOM largely from terrestrial origins during the middle flooding period. During the entire flood season, SUVA254, SUVA260, and E2/E3 exhibited the same trend, that is, decreasing first and then increasing. As a result of the continuous heavy rainfall during the flood season, the nitrogen and phosphorus nutrient content in the channel increased. The algae population did not proliferate in large quantities because of the strong hydrodynamic conditions experienced throughout the flood season. The fluorescence components C2, C3, and C4 exhibited a significant correlation coefficient (P<0.01) with the characteristic parameters (FI, HIX, BIX, and ß:α). All the fluorescence components had a high correlation (P<0.05) with DOC. There was a considerable correlation between fluorescence component C1 and Chla. The principal component analysis revealed that the DOM components in the landscape river during different periods of the flood season exhibited notable differences, and the continuous heavy rainfall during the flood season has a substantial influence on the content of C2, C3, and C4 components in the water body.

16.
Huan Jing Ke Xue ; 42(3): 1391-1402, 2021 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-33742936

RESUMEN

To explore the influence of storm runoff on reservoir organic matter during the flood season, the Lijiahe Reservoir was selected to analyze variations in the content and components of dissolved organic matter (DOM) during four periods (before runoff, flood peak period, 1 week after runoff, and 6 weeks after runoff) using three-dimensional fluorescence spectroscopy parallel factor analysis (EEMs-PARAFAC) and ultraviolet-visible (UV-Vis) spectra. The results showed that:① the turbidity and DOC content of the reservoir increased significantly during the flood peak period (P<0.01) and gradually decreased thereafter; ② the UV-Vis spectrum characteristics showed that a(254) and a(355) were significantly increased in the flood peak period (P<0.01) while E2/E3 and E3/E4 were significantly decreased (P<0.01), indicating that the concentration, relative molecular weight, and degree of DOM humification in the reservoir were increased by storm runoff; ③ four DOM components were identified as terrestrial humus (C1 and C2), microbial humus (C3), and a tryptophan-like component (C4). The fluorescence intensity of the C1-C3 components increased significantly during the flood peak period (P<0.05), indicating that the increase in the DOM humic-like component was caused by the storm runoff. At the same time, a decrease in the fluorescence intensity of the C1-C4 components was observed after the flood peak period, indicating that DOM continuously settled and degraded after runoff; and ④ Pearson's correlation analyses showed that DOM fluorescence intensity and turbidity were significantly correlated (r>0.467, P<0.05), indicating that the observed decrease in DOM content was related to the sedimentation of suspended solids. A principal component analysis (PCA) showed that the water quality in the reservoir reflected the observed characteristics during the different runoff periods. Overall, this study reveals the effects of the storm runoff on DOM content and its components over the short and long term, providing scientific support for the management of drinking water quality.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 244: 118827, 2021 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-32862077

RESUMEN

In this paper, a new method for simultaneous determination of nitrate, COD and turbidity in water based on UV-Vis absorption spectrometry combined with interval analysis was studied. By analyzing the spectral absorption characteristics of nitrate, COD, and turbidity standard solutions and the mixtures of them, the absorption spectra in the range of 225-260 nm, 260-320 nm and 320-700 nm were selected as the characteristic spectra of nitrate, COD and turbidity, respectively. Multiplicative scatter correction was employed to compensate turbidity of the absorption spectra of the mixture solutions in the wavelength range of 225-320 nm. Then, the spectra after turbidity compensation in the range of 225-260 nm was compensated for COD using the method of spectral difference. The original spectra in the range of 320-700 nm, the turbidity compensated spectra in the range of 260-320 nm, and the COD compensated spectra in the range of 225-260 nm were analyzed by PLS algorithm in order to calculate the concentrations of nitrate, COD and turbidity in the mixture solutions. The results showed that this method could simultaneously and accurately determine the concentrations of nitrate, COD and turbidity. After interval analysis, all the correlation coefficients (R2) between the predicted values and the true values of nitrate, COD and turbidity were higher than 0.9, and root mean square error (RMSE) of predicted values were between 0.696 and 2.337.

18.
J Mol Graph Model ; 102: 107798, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33181422

RESUMEN

New D-π-spacer-A model compound dye sensitizers (or dyes) are developed using digital structures for organic dyes sensitized solar cells (DSSCs) applications. Based on our previous studies, the model D-π-spacer-A dyes contain building blocks of a di(p-carboxy)-phenylamine as the electron donor and a perylene monoimide as the electron acceptor. The new D-π-spacer-A dyes are constructed through variations of a set of three model π-spacer units, fluorene, 3,4-ethylenedioxythiophene and thiophene. The new dyes are presented by digital structures of π(ijk) in a digital control Π-matrix. If the chromophore database of the π-units is arranged in a defined manner, the new dyes are therefore designed through selecting of the set of three integers (ijk). Properties such as the UV-vis spectra which are calculated using the time-dependent density functional theory (TD-DFT) determine if the new compounds are suitable for organic solar cell purposes. The same strategy can be applied to donors and acceptors in the D-π-spacer-A model compound in order to robust design and build new organic dyes for DSSCs. The digital structures of the organic compounds enhance the machine driven structure-property relationship establishment once the database is sufficiently comprehensive. The present study demonstrates that new compounds obtained through mixing the π-spacer units of fluorene, 3,4-ethylenedioxythiophene and thiophene, e.g. π121 and π211, result in better dyes in DSSC applications. The concise digital structures of the new dyes are able to achieve a more robust design of the organic dyes and other materials.


Asunto(s)
Energía Solar , Colorantes , Suministros de Energía Eléctrica , Modelos Moleculares , Tiofenos
19.
Huan Jing Ke Xue ; 41(6): 2635-2645, 2020 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-32608778

RESUMEN

The chromophoric dissolved organic matter (CDOM), the main component of dissolved organic matter, affects the morphological characteristics, migration, and conversion of pollutants in water. Based on UV-vis spectra and excitation emission matrix spectroscopy (EEMs) combined with the parallel factor analysis (PARAFAC), the spatial distribution and spectral characteristics were investigated and source analysis of CDOM was performed. Thus, the spatiotemporal differences in the CDOM in Gangnan Reservoir were analyzed. Results showed that a254, a260, a280, and a355 exhibited significant seasonal differences in Gangnan Reservoir, and the order of CDOM concentrations was summer > spring > autumn > winter. There are significant seasonal differences in the E2/E3, E3/E4, E4/E6, and SR of interstitial water CDOM. The concentrations of E2/E3, E3/E4, E4/E6, and SR were high in winter and low in summer. E2/E3 and E3/E4 in autumn and winter were significantly higher than those in spring and summer, and the E3/E4 in autumn and winter was greater than 3.5, which indicates that the CDOM of the autumn and winter sediments has a smaller molecular weight and a lower degree of humification. Protein-like substances (C1), short-wave fulvic acid (C2), and degraded humic substances (C3) were identified by the PARAFAC model, and there was a significant positive correlation among the three fluorescent components (P<0.001). The total fluorescence intensity of CDOM and the fluorescence intensity of each fluorescent component show significant seasonal differences. The total fluorescence intensity and the fluorescence intensity of each component show the highest levels in spring, followed by autumn and winter, and the lowest levels in summer. The proportion of each fluorescent component in autumn and winter and that of each fluorescent component in spring and summer showed no significant difference. There was a significant difference in the proportion of each fluorescent component between autumn/winter and spring/summer. The BIX and FI of CDOM for autumn and winter were higher than those for spring and summer, indicating that the autogenous source of CDOM in autumn and winter is stronger than that in spring and summer, which was consistent with the result of HIX. PCA and Adonis analysis showed that the spectral characteristics of CDOM exhibited obvious seasonal differences (P<0.001). Moreover, the C1, C2, and C3 and water quality parameters (NH4+, NO3-, NO2-, TDN, and TDP) exhibited significant correlation based on linear regression. The results could provide technical support for the control of organic carbon pollution sources and water quality management in Gangnan Reservoir.

20.
Data Brief ; 29: 105245, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32099877

RESUMEN

Lanthanide-containing polyoxometalate (POM) is one of the presently most active groups as the properties of POM can be modified by incorporated transition metal ions. There are several reported transition metal ion contained POMs such as one Ln ion-POM with Keggin POM frameworks and a novel sandwich"-type, which consists of two open Wells-Dawson anions and three Ln ions [1-3]. In this data article, UV-vis spectra and FTIR spectra as well as the elemental analysis are shown for prepared ß-K7H8[Er3O3(SiW9O34)2]·25H2O and ß-K12H5[Sm3O3(SiW9O34)2]·18H2O, these results are intended to provide support for lanthanide-containing POM due to the lack of information on lanthanide-containing POM. The UV-vis spectra and FTIR spectra as well as the elemental analysis are shown for prepared ß-K7H8[Er3O3(SiW9O34)2]·25H2O and ß-K12H5[Sm3O3(SiW9O34)2]·18H2O were not reported in the article [4] are given. The data is related to the research article "Enhancing Electrofluorochromic Efficiency through  C 30 H 31 N 6 + -Sensitized Layer-by-layer Polyoxometalate Films" [4].

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