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To investigate the effect of the interaction between protocatechuic acid (PCA) and gelatin on the functional properties and stability of gelatin-PCA complexes. Gelatin-PCA complexes were prepared by non-covalent and covalent binding. Afterward, the interaction between PCA and gelatin was analyzed using UV-Vis spectroscopy, fluorescence spectroscopy, and Fourier transform infrared spectroscopy. Meanwhile, an analysis was also performed on the antioxidant activity, antibacterial activity, and stability of the complexes. The findings showed a higher PCA binding rate for the covalent complexes than the non-covalent complexes. Additionally, the interaction between PCA and gelatin resulted in the fluorescence quenching of gelatin, with a higher level of fluorescence quenching observed for the covalent binding. Moreover, in addition to excellent DPPH and ABTS+ radical scavenging abilities. Compared with GPCA-2, the noncovalent complex GPCA-1 showed more significant (P<0.05) scavenging abilities against DPPH and ABTS+ free radicals, with clearance rates of 49.71%±2.9% and 38.39%±0.57%, respectively. Gelatin-PCA complexes also exhibited antibacterial activity against Escherichia coli, Listeria monocytogenes, and Salmonella. Moreover, the antibacterial effect of GPCA-1 was more significant (P<0.05), with inhibition zone diameters of 11.31±0.91, 12.57±0.93 and 8.83±0.35 mm for E. coli, L. monocytogenes and Salmonella, respectively. Despite reducing the antioxidant and antibacterial activities of PCA to some extent, the interaction between PCA and gelatin significantly (P<0.05) improved the photostability and thermal stability of PCA. Specifically, the retention rates of PCA in gelatin-PCA covalent complexes after 80 min of UV and heat treatment were 92.58%±0.62% and 90.30%±0.97%, respectively. In conclusion, these findings provide a theoretical basis for the development and utilization of functional gelatin-PCA complex products. [ABSTRACT FROM AUTHOR]

Ink as an important part of documents is a key material evidence in the field of forensic science. Its in-depth study and accurate identification are of great significance for the detection and trial of cases. Different inks may have different volatile components, so these volatile components play an important role in the identification of ink and the judgment of the writing age. According to the different application fields and components, the types and components of ink are sorted out, and various instrument methods for the identification of volatile components are introduced, mainly including UV-Vis spectroscopy, Raman spectroscopy, infrared spectroscopy, fluorescence spectroscopy, gas chromatography，gas-liquid combination method, mass spectrometry，etc. These methods have their own advantages and disadvantages, and are suitable for different inks. In addition, the development of ink volatile component testing methods is prospected, and the existing defects in the current methods are pointed out, in order to provide reference for forensic science document testing workers. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive experiment within the interdisciplinary field of chemical biology, closely aligned with the cutting-edge of the discipline, deeply integrating science and education. Utilizing both chemical and biological methods within an in vitro biochemical reaction system, this study investigates effects of the natural antioxidant quercetin on the redox cycle of myeloperoxidase (MPO) within biological organisms. The mechanism of quercetin affecting the chlorination activity of MPO is clarified through molecular docking techiniques and a series of UV-Vis absorption spectroscopy. The implementation of this experiment aids in broadening students’ perspectives, igniting their interest in scientific research, and enhancing their comprehensive experimental abilities. It offers valuable insights and examples for the development of multidisciplinary innovative talents in chemistry-related majors. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bench-scale experimental study intends to explore the degradation mechanism of methyl orange (MO) using an advanced oxidation system which combines UV with acetylacetone (AA). As a result, the experimental study presented that the UV/AA system was much better than the UV/H2O2 system with respect to the effectiveness of decolorizing MO, as the initial concentration of MO in the wastewater was 15 mg/L and the dosage of AA was 0.5 mmol/L, the degradation rate of MO could be as high as 98.4% after photolysis of 12 min, and in the UV/AA system the degradation of MO was in compliance with the zero-order-kinetic model (R²>0.990) regardless the initial mass concentration. When the value of pH was approximately 2.0, the degradation rate of MO in 6 min. could reach up to 99.3%, an increase of 58.1% higher than that the pH of 9.0 or so. On the other hand, the inorganic anion HCO3- had a significantly inhibitory effect on the system, low concentration of Cl- slightly promoted it, while high concentrations, and SO42- made almost no effects on the degradation rate, and the printing/dyeing auxiliary sodium citrate also exerted notable adverse effect on the degradation of MO. Furthermore, the results of free-radical-capture experiment and the electron paramagnetic resonance (EPR) test indicated that the most of the active-oxides in the UV/AA system was ¹O2. The result of treating printing/dyeing wastewater in terms of TOC indicated that this UV/AA advanced system had a certain degree of mineralization ability; UV-Vis absorption spectroscopy analysis showed that the azo bond was basically broken down in 12 min; and AA concentration decreased as the reaction being in progression. According to the results of analysis using LC-MS, it was speculated the conversion pathway of MO in the degradation process of UV/AA advanced oxidation system. [ABSTRACT FROM AUTHOR]

Synergistic therapeutic effect through the intracellular co-delivery of chemotherapy and biomacromolecule drugs is a novel strategy for improving tumor treatment effectiveness. A triblock copolymer, poly(acrylic acid)-poly(N, Ndiisopropylaminoethyl methacrylate)-poly(N-vinylcaprolactam) (PAA-PDPA-PNVCL), was designed and synthesized for the construction of smart responsive drug carriers. The structure of the polymers was verified by nuclear magnetic resonance spectroscopy (¹H-NMR) and fluorescence spectrophotometer (FL). The transmittances of the polymer solutions under different pH values or temperatures were measured by ultraviolet-visible spectroscopy (UV-Vis). Results showed that the polymer had excellent pH responsiveness and a low critical solution temperature (LCST), which could self-assemble into vesicles with PAA as hydrophilic shell, PDPA as hydrophobic intermediate layer and PNVCL as hydrophilic cavity. Then, the PAA shell layer was crosslinked with disulfide bonds through amide reaction, to improve the structural stability of vesicles and meanwhile introduce the reduction sensitivity. The changes of the particle size, Zeta potential, and morphology of the vesicle under different conditions were studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Results showed that the shell-crosslinked vesicles were uniformly sized spherical structure with good pH value and reduction responsiveness. Their drug encapsulation effect and in-vitro release behavior under different pH values and glutathione (GSH) concentrations were studied by UV-Vis and FT-IR. Results showed that the carriers could achieve zoned and co-loading of hydrophobic small molecule drug (doxorubicin (DOX)) and hydrophilic macromolecular protein drug model (bovine serum protein (BSA)). The hydrophobic layer of PDPA and the crosslinked layer of PAA provided dualblockade for drug leakage. The leakage of drugs under normal physiological conditions was low, and the release of DOX and BSA could only be triggered under simulated tumor microenvironment, that is, weak acid and high concentration of GSH conditions. The smart responsive drug carriers constructed in this paper are expected to achieve co-delivery of chemotherapy and biomacromolecule drugs, which have potential application value to the clinical treatment of tumors. [ABSTRACT FROM AUTHOR]

The leaching of spent lithium-ion battery (LIBs) cathode materials with non-aqueous systems has received widespread attention. In this paper, a binary non-aqueous system of glycerin(Gly)-formic acid(FA)and a ternary non-aqueous system of Gly-FA-choline chloride (ChCl) were used for the leaching of LiCoO2 cathode materials. The effects of leaching time, leaching temperature and liquid-to-solid ratio conditions on leaching rates were investigated. The results indicated that the addition of ChCl was able to significantly improve the leaching rates of the metals. Under the optimal conditions of time 210 min, temperature 120 °C and liquid-solid ratio 100 mL/g, the ternary non-aqueous system achieved leaching efficiencies of 99.77% and 89.09% for Li and Co respectively, higher than the 67.94% and 67.11% for the binary non-aqueous system. The leachate was analyzed by UV-Vis and FT-IR spectroscopy to reveal the leaching mechanism. The results showed that FA was able to reduce Co3+ to Co2+ in LiCoO2. However, Co2+ was present in different forms in the two non-aqueous systems, where the binary system was present as a hexa-coordination and the ternary system as a tetra-coordination. [ABSTRACT FROM AUTHOR]

To improve the utilization rate of pesticides and reduce the economic losses and environmental hazards caused by pesticide loss, the self-assembly layer of poly (octadecylsiloxane) (PODS) was prepared by hydrolysis, self-assembly and polycondensation of octadecyltrichlorosilane (OTS) on the surface of rapeseed meal (RSM) with octadecyltrichlorosilane (OTS) and p-aminoazobenzene (AAB) as modifiers. At the same time, AAB with photoisomerism was attached to RSM surface to synthesize RSM-PODS/AAB pesticide carrier with photoresponsiveness. Its structure and composition were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), UV-Vis spectroscopy and contact angle measurement device. The results showed that the loading rate of modified RSM was 21.4% higher than that of original RSM, and the cumulative release rate of pinoxaden was 83% in 72 h in the dark. The cumulative release rate of RSM-PODS/AAB was 95% after UV-Vis irradiation for 4 h and 92% after sunlight irradiation for 6 h. The application results showed that RSM-PODS/AAB loaded with pesticides had good UV-Vis and sunlight controlled release performance. The light responsive lipophilic pesticide carrier could effectively control the drug release behavior through UV-Vis and sunlight response. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There were various problems with chromogenic agent-based UV-Vis spectroscopic detection, such as a large selection range and an insufficient molar absorption coefficient. This study highlighted the research application of UV-Vis spectroscopy technology in industrial heavy metal detection as well as the detection mechanism. Chromogenic agent-based detection techniques were often utilized in product assessment, wastewater monitoring, and industrial production process control. Due to the limitations of UV-Vis spectroscopy, the combination of the UV-Vis spectrum and other stoichiometry technologies will expand its applications to the detection of industrial heavy metals. [ABSTRACT FROM AUTHOR]

The organic semiconductor poly(3-hexylthiophene) (P3HT) film prepared by the spin-coating method is optimized by dichlorobenzene (o-DCB) solvent added with chloroform (CF). The organic electrochemical transistor (OECT) is obtained using the optimized P3HT film as the channel layer and ion gel as the electrolyte layer. The effect of CF on the roughness and molecular order of P3HT film is inverstigated by atomic force microscopy, UV-visible spectroscopy and Raman spectroscopy. The effect of CF optimization on the electrical properties of the material is studied with a semiconductor parametric analyzer. Results show that CF introduction reduces the roughness of P3HT film and improves the order degree of P3HT molecular arrangement. The CF-optimized OECT exhibits significant synaptic excitatory pulse current characteristics under the stimulation of −0.5 V and −1.0 V electric pulses. Compared to the device without CF optimization, the amplitude of conductance regulation is increased by about twice and 16 times, respectively, along with the improved retention performance. The simulation results show that the accuracy of the neural network based on the CF-optimized OECT in recognizing MNIST（Modified National Institute of Standards and Technology） handwritten digits is increased from 73.6% to 92.7%. This device is expected to play an important role in large-scale neuromorphic computing applications. [ABSTRACT FROM AUTHOR]

Monodisperse carbon nanospheres (CNs-APAM) with different APAM incorporation amounts were prepared by an assisted hydrothermal method using glucose, anionic polyacrylamide (APAM) as raw material. The samples were characterized and tested using SEM, FTTR, XRD, TG, and ultraviolet-visible spectrophotometer (UV-vis). The effects of APAM addition on the dispersion and yield of carbon nano spheres (CNs) and the adsorption performance of CNs on methylene blue (MB) with different APAM additions were investigated. Tt was shown that the best dispersion and highest yield of CNs were achieved at the addition of APAM at 1 20 mg, with the yield up to 21.5 %• The adsorption results showed that CNs-APAM had the best adsorption effect on MB with the maximum adsorption amount of 124.26 mg • g-1 when the addition amount of APAM was 1 20 mg, the adsorption time was about 2 h, the concentration of MB solution was 30 mg/L, and the initial pH of the solution was 100. The fitting results of the adsorption model showed that the process of MB adsorption by CNs-APAM was consistent with Langmuir model with quasi-secondary kinetic model. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Flavonoids have good pharmacological activity and are widely used, but the yield of extracted flavonoids is low and the price is high. In order to explore the new technology of artificial synthesis of flavonoids and synthesis of new flavonoids, natural product paeonol was used as the raw material, and alkali catalyzed condensation reaction between m-hydroxybenzaldehyde and paeonol was carried out to construct intermediate product Ⅰ. Then, at high temperature, dimethyl sulfoxide (DMSO) was used as a solvent, and iodine was catalyzed to induce its oxidation and cyclization to obtain the target product Ⅱ. The structure of the product was determined through comprehensive analysis such as UV, IR, elemental analysis, and nuclear magnetic resonance. The changes in UV spectra of product Ⅰ and product Ⅱ in different concentrations of acid, alkali, and salt solutions were investigated and the reasons were analyzed. The results show that product Ⅰ is 2′,3-dihydroxy-4′-methoxychalone, with a yield of 82.2%. Its UV spectrum varies in different concentrations of acid, alkali, and salt solutions, and it could react with low concentrations of NaOH solution. The product could exist stably within 30 minutes and also easily interact with KNO3 solution, resulting in unstable products. Product Ⅱ is 7-methoxy-3′- hydroxyflavone, with a yield of 92. 0% . It can exist stably for a long time in HCl (4.0 mol / L), NaOH, and KNO3 solutions. This synthesis process overcomes the problem of protecting hydroxyl groups in condensation reactions and achieves efficient synthesis of 7- methoxy-3′-hydroxyflavones. Product Ⅰ failed to form a 4-chromone structure, with one phenolic hydroxyl group on each AB ring. Its stability is greatly affected by the environment, especially in alkaline environments. When using product Ⅰ, the storage environment should be controlled, and the pH should not be higher than 7. Product Ⅱ has a stable conjugated structure, which is less affected by the environment and can also exist stably in strong acid environments. This study has guiding and reference value for the production and application of flavonoids. [ABSTRACT FROM AUTHOR]

An indoor simulation test system with a mud (sediment) water mass ratio of about 1:1 and a period of 56 days was adopted. Six concentration gradient test groups, including the control group, were set up to study the change characteristics of total organic carbon (TOC) content in sediments caused by different levels of exogenous phosphorus input. At the same time, UV-Vis absorption spectroscopy was used to study the effect of phosphorus containing substances on the structural changes of dissolved organic matter in sediments. The experimental results showed that the TOC content in the sediment of each experimental group decreased by 3.60%, 7.08%, 8.09%, 9.33% and 11.80% respectively compared with the control group on the 56th day, indicating that the decomposition of TOC in the sediment of the Yangtze Estuary accelerated with the increase of exogenous phosphorus input. During the test period, the maximum humification degree and aromatization degree of dissolved organic matter in sediments were positively correlated with the input of phosphorus. The molecular weight and aromatic ring structure of dissolved organic matter were positively correlated with the input of exogenous phosphorus, indicating that the increase of exogenous phosphorus input could accelerate the change of dissolved organic matter in sediments. With the increase of test time, the humification degree and aromatization degree of dissolved organic matter with different phosphorus levels increased first, and then began to decline; The molecular weight of dissolved organic matter gradually decreased with the increase of time, and the substituents on its aromatic ring substituents were gradually replaced by more active functional groups. It shows that humus is formed during the reduction of organic carbon content in sediments. As humus continues to decompose, the degree of humification decreases, and the degree of humification is the same as that of aromatization. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chemistry laboratory training is an integral part of chemistry teaching. However, outdated experimental protocols present limitations and can hinder students’ initiative and innate inclination toward exploration. In this study, novel scientific concepts were translated into experimental chemistry teaching. Small fluorescent molecules with aggregation-induced emission and excited-state intramolecular proton transfer properties were prepared using a carbonyl nucleophile addition reaction. The basic photophysical properties of the molecules and their fluorescence response to acid-base stimulation were evaluated experimentally. The non-toxic and non-noxious reagents used for the experiments were refluxed in ethanol for 0.5 h to implement green organic synthesis principles. The experiment was compact and the fluorescence and color changes of the as-synthesized molecules were conspicuous and remarkable. This can stimulate students’ enthusiasm for experimental chemistry. In addition to the basic organic synthesis reaction, this experiment included several modern analysis and characterization methods, such as nuclear magnetic resonance, Fourier-transform infrared spectroscopy, ultraviolet-visible absorption spectroscopy, and fluorescence spectroscopy. We are confident that this intuitive and effective basic experiment can effectively stimulate and cultivate the innate curiosity of students. [ABSTRACT FROM AUTHOR]

Interaction between epigallocatechin gallate (EGCG) and millet bran protein under conditions that simulate human physiological conditions was investigated by Endogenous fluorescence spectroscopy synchronous fluorescence spectroscopy, Three-dimensional fluorescence spectroscopy and ultraviolet-visible spectroscopy. The results indicated that EGCG can greatly quench the endogenous fluorescence of millet bran protein in the mixed of static mode and dynamic mode. Synchronous fluorescence spectroscopy, ultraviolet-visible spectroscopy and three-dimensional fluorescence spectroscopy indicated that EGCG changed the protein peptide backbone and microenvironment of aromatic amino acid residues of millet bran protein. The synchronous fluorescence results showed that they mainly affected the microenvironment around tryptophan residues and reduced the hydrophobicity of the surrounding microenvironment. The binding constants (KA) and site numbers (n) between EGCG and millet bran protein obtained at different temperatures were 8.691 6×104 L/moL, 1.084 8 (290 K); 1.317 0×106 L/moL, 1.300 9 (298 K); 7.868 6×106 L/moL, 1.489 3 (310 K), respectively. According to the thermodynamic parameters, EGCG and millet bran protein were combined by hydrophobic interaction to form a complex. The binding distance (r) between EGCG and millet bran protein was calculated to be about 2.341 8 nm based on the theory of Föster’s non-radiation energy transfer. The theoretical model of the binding ratio between EGCG and millet bran protein at different temperatures was established, and the binding ratio between EGCG and millet bran protein decreased as concentration of EGCG increased, while the temperature had effect on the binding ratio.

Soil dissolved organic carbon (DOC) is the most active part in forest soil carbon pool, the responses of which to climate warming has profound effects on forest carbon cycling. Based on a manipulative soil warming experiment in subtropical evergreen broad-leaved forests, we collected soil solutions in situ and used ultraviolet-visible, infrared and three-dimensional fluorescence spectroscopy analyses to explore the effects of soil warming (+4 °C, 1 year) on soil DOC quantity and quality along the soil profile. The results showed that soil DOC flux remained constant along the soil profile. Soil DOC mainly included two humic-like fractions and one microbial metabolite. Warming significantly decreased soil DOC flux and the abundance of aromatic and hydrophobic components, and increased the amount of low molecular weight carbohydrates. Furthermore, soil warming increased the relative proportion of humic-like fractions in the surface soil layer (0-10 cm) and microbial metabolite in the deep soil layer (30-40 cm), indicating that warming might accelerate microbial turnover in the deep layer. Overall, soil warming not only decreased soil DOC content' but also simplified the composition of soil DOC in subtropical evergreen broad-leaved forests. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the most effective methods for improving the storage density of resistive random access memories (RRAMs) is to fabricate 3D vertical stacking devices. By using BP-DDAT(DDAT: S-1-dodecyl-S ′-(α,α′-dimethyl-α′ ′- aceticacid)trithiocarbonate) as a key 2D template and reversible addition-fragmentation chain transfer (RAFT) reagent, a novel poly(N-vinylcarbazole) covalently functionalized black phosphorus derivative (BP-PVK) is successfully synthesized and well-characterized by infrared spectroscopy, X-ray electron spectroscopy and UV-Vis absorption spectroscopy. The environmental stability and solubility of BP nanosheets are greatly improved. Using BP-PVK as active layer, a double-layer vertically stacked RRAM memory device (17×17 stripe array) with a configuration of Al/BP-PVK/Al/BP-PVK/Al is fabricated. The as-fabricated device shows good bistable electrical switching and non-volatile rewritable performance at room temperature, with an ON/OFF current ratio exceeding 10³, higher production yield of the memory devices and structural uniformity. [ABSTRACT FROM AUTHOR]

Poly(3,4-ethylenedioxythiophene) (PEDOT) is used in organic-inorganic heterojunction based ultraviolet (UV) photodetector due to its good environmental stability, high conductivity and special photoelectric characteristics. The commonly used methods for depositing PEDOT films include solution spin coating, electrochemical polymerization, vacuum evaporation and immersion. In this paper, PEDOT film on the surface of fluorine doped tin oxide (FTO) coated glass conductive glass is obtained by solid-state polymerization, using 2,5-dibromo-3,4-ethylenedioxythiophene (DBEDOT) as monomer. The PEDOT film modified FTO was combined with zinc oxide nano arrays (ZnO NRs) modified FTO to fabricate the organic-inorganic heterojunction based UV photodetector, and the performance of UV photodetection ability was studied. The materials were characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier-transfer infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray powder diffractometry (XRD). The photo-responsivity, response speed and stability of the UV photodetector were examined in detail through current-voltag (I-V), current-time (I-t) and Tafel curves at zero bias voltage under UV irradiation (365 nm, 0.32 mW/cm²). Results showed that the PEDOT film had a large flake structure, which was conducive to the good contact of ZnO NRs to build a better p-n heterojunction. Furthermore, the introduction of PEDOT film effectively solved the problems of short carrier life, high recombination rate of hole-electrons and slow light response speed of ZnO NRs. In a word, the PEDOT film enhanced the optoelectronic performance of ZnO NRs, which possessed high responsivity of 15.34 mA/W, fast response time of 0.159 s/0.162 s (rise time/fall time) under UV irradiation (365 nm, 0.32 mW/cm²) and good stability. [ABSTRACT FROM AUTHOR]

CsPbBr3-Cs4 PbBr6 perovskite composite nanocrystals (NCs) were successfully prepared by mechanochemistry method at room temperature, introducing trace amounts of methanol and oleylamine as ligands. The nanocrystals were tested by powder X-ray diffraction (XRD), elemental content analysis (EDS), ultraviolet-visible spectroscopy (UV-Vis), photoluminescence (PL) spectroscopy and transmission electron microscopy (TEM). Compared with the samples without methanol, the luminescence intensity of the samples with 0.85 mL methanol increases by 58%, and the quantum yield (PLQY) increases from 11% to 55%. Moreover, the presence of Cs4 PbBr6 in the composite NCs improves the stability of the samples at room temperature. This experiment confirm that the introduction of methanol in the mechanochemistry preparation process could adjust the composition of the complex nanocrystals, thus significantly improving the luminescence intensity and stability of the products, which provides a new idea for the synthesis of luminescent nanocrystals at room temperature. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND There are differences in the production characteristics, chemical composition, coloration mechanism and formation conditions of green tourmaline from different producing areas. At present, the mineral species and coloration mechanism of Tanzanian green tourmaline have not been solved, which makes it difficult for its scientific identification and quality rating. OBJECTIVES To study the mineralogical characteristics and coloration mechanism of Tanzanian green tourmaline. METHODS The mineral component was analyzed by infrared spectroscopy and Raman spectroscopy. Microtexture was characterized by polarized light microscopy. Electron probe microanalyzer, and ultraviolet-visible (UV-Vis) spectroscopy were applied to analyze the chemical composition. RESULTS The main mineral component of tourmaline in Tanzania was MgO tourmaline, which was characterized by single crystal, small grain, no cleavage, and split development, and can be used as a gemstone. The main chemical component of green tourmaline was SiO2, Al2O3, MgO and B2O3, with average contents of 37.52%, 36.26%, 9.65% and 8.42%, respectively. In addition, it contained a small amount of FeO, Cr2O3 and TiO2. Combined with the absorption spectrum in the ultraviolet region of 440nm, 600nm and 680nm in UV-Vis spectroscopy, it was concluded that the tiny amounts of Cr3+ replacing Al3+ into the crystal lattice was the main cause of the green color. CONCLUSIONS The mineralogical characteristics and coloration mechanism of green tourmaline in Tanzania was confirmed, which provides a theoretical basis for the scientific identification, further quality evaluation and utilization.

Two novel stigmasterol derivatives as gelators are synthesized，and named as compounds 1 and 2， respectively. The structure and properties of gels are studied by scanning electron microscopy（SEM），Fourier transform infrared spectroscopy（FT-IR）and UV-Vis spectrophotometer. The results of the gelation properties of compounds 1 and 2 show that they could gelate in DMSO and methanol. Compound 1 also forms a stable gel in DMSO/water mixed solvents at a volume ratio of 9∶1，8∶2，and 7∶3，respectively. In addition，when compounds 1 and 2 are gelated at a mass concentration of 12 mg/mL in DMSO，the gel-sol phase transition temperatures（Tgel）of the two compounds are 51 and 46 ℃，respectively，indicating that the thermal stability of their gelation decreases significantly with the increase of steroidal structural units in the gelator. With the increase of steroid structural units in the gelators，the thermal stability of the gel formation decreases significantly. On this basis，the gel prepared by compound 1 is used as the carrier，and its encapsulation and release in rhodamine B and methylene blue，as well as the anticancer drug doxorubicin are studied by UV-Vis spectroscopy. The results show that the prepared gels could be used as a drug carrier，and the maximum release value reaches 84% in water at 240 min. Furthermore，this study may provide a useful idea for the preparation of stigmasterol derivative gels and its application as a drug carrier in drug delivery. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: There are differences in the production characteristics, chemical composition, coloration mechanism and formation conditions of green tourmaline from different producing areas. At present, the mineral species and coloration mechanism of Tanzanian green tourmaline have not been solved, which makes it difficult for its scientific identification and quality rating. OBJECTIVES: To study the mineralogical characteristics and coloration mechanism of Tanzanian green tourmaline. METHODS: The mineral component was analyzed by infrared spectroscopy and Raman spectroscopy. Microtexture was characterized by polarized light microscopy. Electron probe microanalyzer, and ultraviolet-visible (UV-Vis) spectroscopy were applied to analyze the chemical composition. RESULTS: The main mineral component of tourmaline in Tanzania was MgO tourmaline, which was characterized by single crystal, small grain, no cleavage, and split development, and can be used as a gemstone. The main chemical component of green tourmaline was SiO2, Al2O3, MgO and B2O3, with average contents of 37.52%, 36.26%, 9.65% and 8.42%, respectively. In addition, it contained a small amount of FeO, Cr2O3 and TiO2. Combined with the absorption spectrum in the ultraviolet region of 440 nm, 600 nm and 680 nm in UV-Vis spectroscopy, it was concluded that the tiny amounts of Cr3+ replacing Al3+ into the crystal lattice was the main cause of the green color. CONCLUSIONS: The mineralogical characteristics and coloration mechanism of green tourmaline in Tanzania was confirmed, which provides a theoretical basis for the scientific identification, further quality evaluation and utilization. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For sensitive and rapid detection of iodine ions (I-), citric acid and ethylenediamine were used as raw materials to synthesize carbon dots(CDs) with blue emission through a one-step hydrothermal method. The structure and optical properties of CDs were characterized by transmission electron microscopy (TEM), ultraviolet-visible absorption spectroscopy(UV-vis), Fourier transform infrared spectroscopy (FTIR) and fluorescence spectroscopy, and the CDs were used to detect I- in water samples to investigate the detection effect and quenching mechanism. The results showed that I- can specifically recognize and quench the fluorescence of CDs, and the quenching mechanism is static quenching. The concentrations of I- and the fluorescence intensity of CDs have a good linear response in the range of 20-90 µmol/L, and the detection limit is 1.743 µmol/L. In addition, the recovery experiment shows that this method can be successfully applied to the detection of I- in real water samples. [ABSTRACT FROM AUTHOR]

BACKGROUND As a new kind of jade, yellow-green alunite jade is difficult to positively identify and evaluate due to the lack of research. Yellow-green alunite jade is a new type of jade that has appeared on the market in recent years. At present, there is relatively insufficient research on its gemological mineralogical characteristics, which makes it difficult for its scientific identification and quality evaluation. OBJECTIVES To study the mineralogical characteristics and coloration mechanism of yellow-green alunite jade. METHODS Infrared spectroscopy, X-ray diffraction, Raman spectroscopy, scanning electron microscope, laser ablation-inductively coupled plasma-mass spectrometry and ultraviolet-visible spectroscopy were applied to analyze the mineral component, microtexture, and chemical composition. RESULTS The main mineral component of yellow-green alunite jade was alunite with a cryptocrystalline texture and grain size of less than 5μm. The very fine texture identified it as a delicate jade, but due to lack of interwoven fibric or scaly texture, its toughness was relatively poor. The alunite jade was composed of O, Al, S and K. The contents of transition metals such as V, Fe, Cr were relatively high, with average contents of 23591.52μg/g, 4717.99μg/g and 2077.67μg/g, respectively. Combined with the absorption spectrum in the ultraviolet region of 500nm and 826nm in the ultraviolet-visible spectroscopy, it was concluded that the isomorphous substitution of Al3+ by V3+, Cr3+ and Fe3+ was the main cause of the yellow-green color. The texture of weathering crust of alunite jade was relatively coarse. The mineral components were alunite, quartz, goethite with minor anatase. Yellowish-brown color of weathering crust was due to the serious pigmentation by limonite, and especially goethite. CONCLUSIONS The study confirmed the mineralogical characteristics and coloration mechanism of yellow-green alunite jade, which provides a theoretical basis for the scientific identification and further quality evaluation.

Polyvinylidene fluoride (PVDF) and tetrabutyl titanate (TBOT) are dissolved in a mixed solvent of N, N'- dimethylformamide (DMF) and acetone to electrospun into a fiber membrane. Then, TBOT contained in the electrospun fiber membrane was reduced to titanium dioxide (TiO2) by a one-step hydrothermal method at 150 °C. The PVDF fiber membrane material with TiO2 grown in situ on the surface and inside of the fiber was obtained. The morphology and structure of TiO2 grown on PVDF fibers in situ were determined by scanning electron microscopy (SEM), thermal gravity (TG), X-ray diffractometer (XRD) and Fourier infrared absorption spectroscopy (FT-IR). Then, the degradation effect of the composite film on the three organic dyes (rhodamine B, methyl orange and methylene blue) was tested by UV-visible spectroscopy. Finally, the gravity-driven method was used to separate the oil-water mixture, and the contact angle of the composite membrane to water and oil was tested to explore the oil-water separation effect of the composite membrane. Results show that the composite membrane has a good degradation effect on organic dyes such as rhodamine B, methyl orange, methylene blue. The composite membrane also has good lipophilic and hydrophobic properties. It is separated by a mixture of carbon tetrachloride and water. The composite membrane can effectively realize oil-water separation, and the oil-water separation efficiency can be as high as 98.2%. [ABSTRACT FROM AUTHOR]

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Organic filters in conventional sunscreens generally have poor photo stability and can easily penetrate through stratum corneum and dermis into the blood vessel, thus causing potential health-threatening issues. Polydopamine (PDA) nanoparticles can be formed by self-polymerization of dopamine. Inspired by its excellent anti-ultraviolet, free radical scavenging and adhesion properties, the titanium dioxide (TiO2) precursor is prepared by the sol-gel method and blended with dopamine hydrochloride to prepare PDA-TiO2 hybrid nanoparticles. Infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible absorption spectroscopy (UV-Vis), thermogravimetric analysis (TGA) and skin penetration experiments were used to characterize the basic structures and properties of nanoparticles. Under the synergistic effect of PDA and TiO2, the particles have highly efficient UV protection. By simply adjusting the reaction material ratio, it was found that the more dopamine content, the better UV absorption effect was obtained, and it showed better UV absorption performance than small particle size PDA. Therefore, PDA-TiO2 (1/10) (m (DA)∶m(TiO2)=1∶10) had the best UV absorption effect. The PDA-TiO2 (1/10) was introduced as the sole active ingredient to formulating sunscreen, whose sun protection factor (SPF) values could reach 33.7, which can meet daily sun protection needs. Most importantly, PDA had good bioadhesion and can effectively prevent the penetration of PDA-TiO2 hybrid nanoparticles. The thickness of the stratum corneum of the human body was about 15—20 μm. Upon comparing the PDA-TiO2 with commercially available benzophenone small molecule sunscreens, it was found that the skin permeability of PDA-TiO2 was significantly reduced. The penetration depth was 9 —17 μm, mainly distributed in the upper and middle parts of the stratum corneum of the skin. It is not easy to enter the human body and will not pose a potential threat to skin health. The commercially available benzophenone sunscreen small molecules had a skin penetration of 18 —35 μm, indicating that they penetrate the stratum corneum to reach the living epidermis and enter the human body. Therefore, the prepared nanoparticles have excellent UV resistance and biocompatibility, ensuring their excellent performance and safe use in sunscreens. [ABSTRACT FROM AUTHOR]

In this article, the research works combing spectroscopy analysis with molecular docking calculations to explain the interaction between protein, DNA, and viral nudec acid with Ligands on molecular level were summarized. The changes in the intensity and position of spectra signals obtained by spectroscopy Instruments including UV-visible spectroscopy, fluorescence spectrum, circular dichotic spectrum, Fousier transform infrared spectrometer and three-dimensional fluorescence spectrum were discussed, witch could directly or indirectly obtain information about the structure changes of the macromolecule, the influence on specific groups, and the thermodynamic parameters when macromolecules interact with probes. Meanwhile, molecular docking calculations can sinus[ate the interactions between Ligands and receptor, such as docking position, binding energy, type and distance of the interactions, etc. Combining molecular docking with spectroscopy makes the analysis of binding mechanism between receptor and Ligands more accurate and rehab. Finally, the research works in thus field were summarized and there developments in the future were also prospected. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Quaternized chitosan/nano-zinc oxide (QAC/ZnO) hybrid colloidal particles were prepared by the self-assembly of quaternized chitosan (QAC), L-cysteine (L-cys) and the precursor of nano-zinc oxide Zn(CH3COO)2·2H2O. The chemical composition of QAC/ZnO hybrid colloidal particles was determined by Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and thermogravimetic analysis(TG). The morphology and particle size of the hybrid colloidal particles were investigated in detail by means of Zeta potential analyzer, nanoparticle size analyzer and transmission electron microscopy (TEM). The ultraviolet transmittance, oxidation resistance, photocatalytic activity and cytotoxicity of the hybrid colloidal particles were studied by UV-Vis spectroscopy and the in vitro cell experiments. The results show that spherical QAC/ZnO hybrid colloidal particles can be successfully prepared by the selfassembly of QAC, L-cys and the precursor of nano-zinc oxide, and the size of the hybrid colloidal particles can be controlled by the concentration of nano-zinc oxide precursor. QAC/ZnO hybrid colloidal particles have good ultraviolet shielding property, excellent antioxidant property and low cytotoxicity. Moreover, the photocatalytic activity of the QAC/ZnO hybrid colloidal particles are significantly reduced in comparison with ZnO. It is expected to be used in cosmetics as an ultraviolet absorbent. [ABSTRACT FROM AUTHOR]