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1-Phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. UV-Vis spectra and fluorescence spectra were measured. Density functional theory calculations on the structure of the title compound were performed at the B3LYP/6-311G** level of theory. NPA atomic charge distributions indicate that, although the S atom in the thienyl ring loses coordination capacity, the title compound still may be used as a potential multi-dentate ligand to coordinate with metallic ions. The calculation of the second order optical nonlinearity was carried out. Natural bond orbital analyses indicate that the electronic absorption bands are mainly derived from the contribution of nâπ* and πâπ* transitions. Fluorescence spectra determination shows that the title compound is a potential orange-light emitting material.
Assuntos
Elétrons , Pirazóis/química , Cristalografia por Raios X , Fluorescência , Pirazóis/síntese química , Teoria Quântica , TermodinâmicaRESUMO
Rational design of layered double hydroxide (LDH) electrodes is of great significance for high-performance supercapacitors (SCs). Herein, ultrathin cobalt-nickel-magnesium layered double hydroxide (CoNiMg-LDH) nanosheets with plentiful oxygen vacancies are synthesized via sacrificial magnesium-based replacement reaction at room temperature. Self-doping and mild reduction of magnesium can significantly increase the concentration of oxygen vacancies in CoNiMg-LDH, which promotes the electrochemical charge transfer efficiency and enhances the adsorption ability of electrolytes. Density functional theory (DFT) calculations also indicate that Mg2+ doping can decrease the formation energy of oxygen vacancies in CoNiMg-LDH nanosheets, which increases the concentration of oxygen vacancies. Thus, the assembled asymmetric supercapacitor CoNiMg-LDH//Actived Carbon accomplishes a superior capacity of â¼ 333 C g-1 (208 F g-1) at 1 A g-1 and presents a gravimetric energy density of 73.9 Wh kg-1 at 0.8 kW kg-1. It presents only 13% capacity loss at 20 A g-1 after 5000 cycles. This discovery emphasizes the positive role of magnesium in regulating oxygen vacancies to improve the performance of supercapacitors, which should be beneficial for extending the scope of superior SCs active materials.
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A co-fermentation process involving Yarrowia lipolytica and Trichoderma reesei was studied, using distillers grains (DGS) as feedstocks for erythritol production. DGS can be effectively hydrolyzed by cellulase in the single-strain culture of T. reesei. One-pot solid state fermentation for erythritol production was then established by co-cultivating Y. lipolytica M53-S with the 12 h delay inoculated T. reesei Rut C-30, in which efficient saccharification of DGS and improved production of erythritol were simultaneously achieved. The 10:1 inoculation proportion of Y. lipolytica and T. reesei contributed to the maximum erythritol production of 267.1 mg/gds under the optimal conditions including initial moisture of 55%, pH of 5.0, NaCl addition of 0.02 g/gds and DGS mass of 200 g in 144 h co-cultivation. Being compared with the attempts to produce erythritol from other raw materials, the one-pot SSF with DGS is proposed to be a potential strategy for efficient and economical erythritol production.
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Celulase , Hypocreales , Trichoderma , Yarrowia , Eritritol , FermentaçãoRESUMO
In the crystal of the title compound, 2C(5)H(7)N(2) (+)·C(4)N(4)S(6) (2-)·H(2)O, inter-molecular N-Hâ¯S and N-Hâ¯N hydrogen bonds link four cations and two dianions into a centrosymmetric cluster. The crystal packing is further consolidated by π-π inter-actions between the five- and six-membered rings of neighbouring clusters [centroid-centroid distances = 3.692â (3), 3.718â (3), 3.660â (3) and 3.696â (3)â Å] and via O-Hâ¯N, O-Hâ¯S and N-Hâ¯O hydrogen bonds involving the uncoordinated water mol-ecules.
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An efficient Z-scheme Co3O4/g-C3N4 heterojunction photocatalyst was developed via in-situ forming Co3O4 nanocubes on the g-C3N4 nanosheet in the hydrothermal process. The obtained photocatalyst exhibited high photocatalytic activity for the visible-light-driven catalytic reduction of Cr(VI) and catalytic oxidation of tetracycline (TC). Among the as-synthesized catalysts, Co3O4/g-C3N4-0.04 (the mass ratio of g-C3N4 to Co3O4 is 0.04) sample exhibits the most efficient catalytic activities. The photocatalytic reduction and photocatalytic oxidation efficiencies of Co3O4/g-C3N4-0.04 can obtain 81.3 and 92.6 %, respectively. Moreover, the TC is mineralized in the course of photocatalytic degradation, 72.2% of TOC is removed from the reaction system. In addition, the apparent quantum efficiency for the removal of Cr(VI) was also obtained and the the Co3O4/g-C3N4-0.04 could achieve the highest apparent quantum efficiency among the samples. The enhancing photocatalytic activities originated from the efficient interfacial charge migration and separation obtained in Co3O4/g-C3N4-0.04, which is preliminarily confirmed by the photoluminescence spectra, time-resolved photoluminescence spectra and the photoelectrochemical characterizations. Finally, we speculate that the Co3O4/g-C3N4 heterostructures follow a more reasonable Z-scheme charge transfer in this study, which is confirmed by analyzing the results of electron paramagnetic resonance, radical scavenging experiments, and theoretical calculations.
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In the title compound, C(25)H(20)Br(2)N(2) (2+)·2NO(3) (-), the cation lies on a twofold rotation axis which imposes disorder of the dibromo-fluorene unit. In addition, the unique nitrate anion is disordered over two general sites of equal occupancy. The crystal structure is stabilized by inter-molecular N-Hâ¯O hydrogen bonds.
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Biomass porous carbon materials are ideal supercapacitor electrode materials due to their low price, rich source of raw materials and environmental friendliness. In this study, an ultrasonic-assisted method was applied to synthesize the rice-straw-based porous carbon (UPC). The obtained UPC exhibited a two-dimensional structure and high specific surface area. In addition, the electrochemical test results showed that the UPC with a 1 hour ultrasonic treatment and lower activation temperature of 600 °C (UPC-600) demonstrated optimal performance: high specific capacitances of 420 F g-1 at 1.0 A g-1 and 314 F g-1 at a high current of 10 A g-1. Significantly, the symmetric supercapacitors showed a high energy density of 11.1 W h kg-1 and power density of 500 W kg-1. After 10 000 cycles, 99.8% of the specific capacitance was retained at 20 A g-1. These results indicate that UPC-600 is a promising candidate for supercapacitor electrode materials.
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Biochar is increasingly considered in addressing bioprocess issues due to its strong adsorbability and excellent compatibility to microbes. Here, biochar was first applied in aerobic solid-state fermentation (SSF) for erythritol production. Biochars derived from different agricultural wastes under various pyrolysis temperatures were evaluated, and wheat straw pyrolyzed at 300 °C (WSc) performed the best in enhancing fermentative erythritol production, with a dosage of 4% (w/w). In this procedure, cell-biochar-substrate "microzones" were formed, which was conductive to cell growth and attachment, and hence contributed enhanced enzyme activities, oil consumption, and erythritol production. The resultant erythritol productions of batch and fed-batch fermentations were 207.3 and 222.5 mg/gds, respectively. In repeated-batch fermentation, high cell viability and robust erythritol synthesis were maintained throughout seven cycles. This study demonstrates that SSF can be remarkably facilitated by biochar addition, suggesting a new perspective of biochar application in microbiological processes.
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The title compound, 5-ethoxycarbonly-6-methyl-4-phenyl-2-thioxo-1,2,3,4-tetrahydropyrimidine, has been synthesized and characterized by elemental analysis, IR, UV-vis and X-ray single crystal diffraction. Ab initio calculations have been carried out for the title compound by using B3LYP and HF methods at 6-31G* basis set. The calculated results show that the predicted geometries can reproduce the structural parameters, although the intermolecular interactions have some influences on the molecular geometry in the solid state. Predicted vibrational frequencies by two methods are consistent with each other. They have been assigned and compared with experimental IR spectra. The theoretical electronic absorption spectra have been calculated by both TD-DFT and HF-CIS methods, and the results indicate that only the former can approximately predict the electronic spectra for the title compound. Molecular orbital coefficients analyses suggest that the electronic transitions are mainly assigned to n-->pi* and pi-->pi* electronic transitions. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between C(p,m)(0), S(m)(0), H(m)(0) and temperatures.
Assuntos
Modelos Químicos , Pirimidinas/química , Pirimidinas/síntese química , Tionas/química , Tionas/síntese química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Espectrofotometria Infravermelho , Termodinâmica , VibraçãoRESUMO
3-Phenylamino-4-phenyl-1,2,4-triazole-5-thione was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. Density functional theory calculations of the structure, natural bond orbitals, atomic charge distributions and thermodynamic functions of the title compound were performed at B3LYP/ 6-311G** and PBE1PBE/6-311G**levels of theory, respectively. NPA atomic charge distributions indicate that the title compound can be used as a potential multi-dentate ligand to coordinate with various metallic ions. Calculation of the second order optical nonlinearity was also carried out. The thermodynamic properties of C(0)(p,m), S(0)(m) and H(0)(m) were calculated and correlative equations between the thermodynamic properties and temperatures were also obtained.
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Tionas , Triazóis , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Cristalografia por Raios X , Fungos/efeitos dos fármacos , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana , Modelos Químicos , Estrutura Molecular , Termodinâmica , Tionas/síntese química , Tionas/química , Triazóis/síntese química , Triazóis/químicaRESUMO
The title compound, C(16)H(13)FO(2), was prepared from 4-methoxy-hypnone and 4-fluoro-benzophenone by Claisen-Schmidt condensation. All the bond lengths and bond angles are in normal ranges. The dihedral angle formed by the two benzene rings is 33.49â (2)°. The crystal packing is stabilized by inter-molecular C-Hâ¯O hydrogen-bonding inter-actions.
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In the title compound, C(16)H(10)O(6), the complete mol-ecule is generated by a crystallographic centre of symmetry. In the crystal, O-Hâ¯O hydrogen bonds link the mol-ecules into (100) sheets and C-Hâ¯O links also occur.
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Responsive molecular chromic materials have shown potential applications in molecular optical switches and sensor devices as they undergo reversible colour changes upon application of external stimuli. Herein, six host-guest coordination polymers 1-6 and one organic supramolecular compound 7 containing viologens have been synthesized under hydrothermal conditions. Compound 1 shows thermochromic behavior with a colour change from green to blue upon heating at 150 °C in air. Compounds 3, 4 and 7 display photochromic behaviors with a colour change from pale yellow to green under UV light, visible light or sunlight. The relationship between their structures and chromic behaviors has been discussed. Thermo/photochromic mechanisms have been investigated by infrared spectroscopy, powder X-ray diffraction analysis, UV-vis absorption spectroscopy, electron paramagnetic resonance spectroscopy, and X-ray photoelectron spectroscopy. The results demonstrate the generation of viologen radicals caused by thermo/photo-induced electron transfer. It is found that compound 4 can be used as an inkless and erasable printing medium. In addition, compounds 3, 4, and 7 can be used as anti-counterfeiting materials for QR codes. Our findings demonstrate the possibility of applying thermo/photochromic coordination polymers in molecular devices.
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Oil crop wastes are attractive feedstocks in microbial processes due to their low cost. However, the product yields can be limited by their undesirable nitrogen surplus. Present study proposed a one-step solid state fermentation (SSF) method for producing erythritol from unrefined oil crop wastes using a modified strain Y. lipolytica M53-S. Enhanced erythritol production (185.4â¯mg/gds) was obtained from peanut press cake mixed with 40% sesame meal and 10% waste cooking oil. The process was performed at pH 4.0 in 5â¯L flasks, with initial moisture content, NaCl addition, and inoculum size of 70%, 0.02â¯g/gds, and 7.5â¯×â¯104â¯cells/gds, respectively. This procedure showed advantages in terms of lower material cost than that of submerged fermentation and shorter culture cycle (96â¯h) than other SSF processes. In repeated-batch fermentation, erythritol was continuously produced for seven cycles. This study presents a feasible approach in developing an efficient erythritol cultivation from nitrogen-rich wastes.
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Eritritol , Yarrowia , Fermentação , Glicerol , NitrogênioRESUMO
Mg-substituted α- and ß-phase nickel hydroxides with high specific capacitance and good stability have been synthesized via sacrificial metal-based replacement reaction. 2D α- and ß-phase nickel-magnesium hydroxide (NiMg-OH) have been synthesized by sacrificing magnesium (Mg) powder with nickel salt aqueous solutions. Interestingly, the phase of the obtained NiMg-OH can be controlled by adjusting the nickel precursor. As well, the Mg powder is used not only as Mg source but also alkali source to form NiMg-OH. The α-phase nickel-magnesium hydroxide sample (α-NiMg-OH) exhibits lager surface area of 290.88 m2 g-1. The electrochemical performances show that the α-NiMg-OH presented a superior specific capacitance of 2602 F g-1 (1 A g-1) and ß-phase nickel-magnesium hydroxide sample (ß-NiMg-OH) exhibits better stability with 87% retention after 1000 cycles at 10 A g-1. The hybrid supercapacitor composed of α-NiMg-OH and activated carbon (AC) display high storage performance and cycle stability, it presents 89.7 F g-1 (1 A g-1) and of 0-1.6 V potential window and it maintains capacitance retention of 84.6% subsequent to 4000 cycles.
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The title compound, 1-acetyl-3-(2,4-dichloro-5-fluoro-phenyl)-5-phenyl-pyrazoline, has been synthesized and characterized by elemental analysis, IR, UV-vis and X-ray single crystal diffraction. Density functional (DFT) calculations have been carried out for the title compound by using B3LYP method at 6-31G* basis set. The calculated results show that the predicted geometry can well reproduce the structural parameters. Predicted vibrational frequencies have been assigned and compared with experimental IR spectra and they are supported each other. The theoretical electronic absorption spectra have been calculated by using TD-DFT method. Molecular orbital coefficients analyses suggest that the above electronic transitions are mainly assigned to n-->pi* and pi-->pi* electronic transitions. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between C(p,m)(0),S(m)(0),H(m)(0) and temperatures.
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Cristalografia por Raios X/métodos , Pirazóis/análise , Pirazóis/síntese química , Elétrons , Modelos Moleculares , Estrutura Molecular , Pirazóis/química , Espectrofotometria Infravermelho , Temperatura , Termodinâmica , VibraçãoRESUMO
1-Acetyl-3-(4-chlorophenyl)-5-(4-methylphenyl)-2-pyrazoline has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. Density functional (DFT) calculations have been carried out for the title compound by using the B3LYP method at the 6-311G** basis set level. The calculated results show that the predicted geometry can reproduce well the structural parameters. Predicted vibrational frequencies have been assigned and compared with experimental IR spectra and they are supported each other. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between C(0)(p, m), S(0)(m), H(0)(m) and temperatures.
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Pirazóis/química , Pirazóis/síntese química , Espectrofotometria Infravermelho/métodos , Algoritmos , Cristalografia por Raios X/métodos , Modelos Moleculares , Estrutura Molecular , TermodinâmicaRESUMO
The title compound, [Cu(2)(C(13)H(14)N(3))(2)Cl(2)], is a neutral dimeric copper(II) complex. The two Cu(II) atoms are asymmetrically bridged by two chloride ions. Each Cu(II) atom is also bound to the three N atoms of a deprotonated tridentate Schiff base ligand, giving a distorted square-pyramidal N(3)Cl(2) coordination environment overall. The dinuclear complex lies across an inversion centre in the space group P1. This work demonstrates the effect of ligand flexibility and steric constraints on the structures of copper(II) complexes.
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The potential tridentate Schiff base ligand 2-[1-(2-pyridyl-methyl-imino)eth-yl]pyrrole (HL) was synthesized from the condensation of 2-acetyl-pyrrole with 2-amino-methyl-pyridine. The title compound, [Cu(C(12)H(12)N(3))Cl], was synthesized from HL and copper(II) chloride using triethyl-amine as a base to deprotonate the pyrrole NH group. The title compound is a monomer and the central copper(II) ion is bound to three N atoms of the deprotonated tridentate ligand and to one chloride ion in a square-planar N(3)Cl coordination.
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The Fourier transform Raman and Fourier transform infrared spectra of 3,4-dichlorobenzyl alcohol were recorded in the solid phase. The equilibrium geometry, harmonic vibrational frequencies, infrared intensities and Raman scattering activities, depolarization ratios, reduced masses were calculated by HF and density functional B3LYP method with the 6-311 G** basis set. The scaled theoretical wavenumbers showed very good agreement with the experimental values. The thermodynamic functions of the title compound were also performed at HF/6-311G** and B3LYP/6-311G** levels of theory. A detailed interpretations of the infrared and Raman spectra of 3,4-dichlorobenzyl alcohol is reported. The theoretical spectrograms for FT-IR spectra of the title molecule have been constructed.