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101.
Akram Abi Anqi Wang Hans-Joachim Jördening 《Applied biochemistry and biotechnology》2018,186(4):861-876
The first continuous production system of laminaribiose from sucrose and glucose in a bienzymatic reaction is reported in this study. Immobilized laminaribiose phosphorylase and sucrose phosphorylase were used in a packed bed reactor system comprising of a 3-cm glass column at 35 °C with a steady feeding flow rate of 0.1 ml/min. Factors affecting product formation including enzyme ratio, peal concept (both enzymes in one pearl or in separate pearls), and pearl size were studied. An enzyme ratio of 2:1 of laminaribiose phosphorylase (LP) to sucrose phosphorylase (SP) when encapsulated separately in bigger size peals resulted in higher concentration of product. Laminaribiose (0.4 g/(L h)) is produced in the optimized system at steady state. The reaction system proved to be operationally stable throughout 10 days of continuous processing. A half-life time of more than 9 days was observed for both biocatalysts. 相似文献
102.
Malik Adnan Nafees Ayesha Ali Akram Butt Muhammad Naeem 《The European Physical Journal C - Particles and Fields》2022,82(2):1-12
The European Physical Journal C - Much theoretical effort and automatization are required to confront new physics models with experimental data for many types of particle reactions at future... 相似文献
103.
Using the Hubbard model in the framework of the tight-binding formulation, we studied the effects of the electron–electron (e–e) interaction on the indirect magnetic exchange coupling between the magnetic impurities embedded in triangular graphene nanoflakes. The results show that the magnitude of the coupling enhances in the presence of the e–e interaction and Rashba spin–orbit interaction (RSOI). The RKKY coupling magnitude depends on the impurity positions in nanoflake and the size of the system, as well. 相似文献
104.
Novel pyrimido[4,5-b]quinoline-tetraones were prepared by the three-component reaction of 2-hydroxynaphthalene-1,4-dione, 6-amino-uracils, and aromatic aldehydes in aqueous media and catalyzed by p-toluenesulfonic acid. This protocol provides a simple one-step procedure with the advantages of easy workup, good yield of products, and environmental friendliness. 相似文献
105.
In the present analysis, the influence of heat and mass transfer on the peristaltic flow of a hyperbolic tangent fluid in an asymmetric channel has been discussed. The highly nonlinear equations are simplified under lubrication approach. The perturbation and numerical solutions of the problem are not only discussed but the validity of the results is also being checked. The graphical results of the problem under discussion are also being brought under consideration to see the behavior of various physical parameters. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
106.
107.
Novel inorganic–organic yolk–shell microspheres based on Preyssler‐type NaP5W30O11014? polyoxometalate and MIL‐101(Cr) metal–organic framework (P5W30/MIL‐101(Cr)) were synthesized by reaction of K12.5Na1.5[NaP5W30O110], Cr(NO3)3·9H2O and terephthalic acid under hydrothermal conditions at 200°C for 24 h. The as‐prepared yolk–shell microspheres were fully characterized using various techniques. All analyses confirmed the incorporation of the Preyssler‐type NaP5W30O11014? polyoxometalate into the three‐dimensional porous MIL‐101(Cr) metal–organic framework. The results revealed that P5W30/MIL‐101(Cr) demonstrated rapid adsorption of cationic methylene blue (MB) and rhodamine B (RhB) with ultrahigh efficiency and capacity, as well as achieving rapid and highly selective adsorption of MB from MB/MO (MO = methyl orange), MB/RhB and MB/RhB/MO mixtures. The P5W30/MIL‐101(Cr) adsorbent not only exhibited a high adsorption capacity of 212 mg g?1, but also could quickly remove 100% of MB from a dye solution of 50 mg l?1 within 8 min. The effects of some key parameters such as adsorbent dosage, initial dye concentration and initial pH on dye adsorption were investigated in detail. The equilibrium adsorption data were better fitted by the Langmuir isotherm. The adsorption kinetics was well modelled using a pseudo‐second‐order model. Also, the inorganic–organic hybrid yolk–shell microspheres could be easily separated from the reaction system and reused up to four times without any change in structure or adsorption ability. The stability and robustness of the adsorbent were confirmed using various techniques. 相似文献
108.
The demand for nanoparticles is increasing day by day due to their wide range of applications in various areas including pharmaceutical industry. Nanoparticles are formally synthesized by chemical methods in which the toxic and flammable chemicals are used. Synthesis of nanoparticles from various biological systems has been reported, but among all, biosynthesis of nanoparticles from plants is considered as the most suitable method. The current study confirms the potential of aqueous extract of Melissa officinalis grown under in vitro condition for the green synthesis of silver nanoparticles (AgNPs). Also, we revealed the cytotoxicity, antioxidant, and anti-acute myeloid leukemia effects of AgNPs compared to mitoxantrone in a leukemic mouse model. The synthesized AgNPs were characterized using several techniques including UV–Vis., FT-IR, TEM, FE-SEM, and EDS. In vivo experiment, induction of acute myeloid leukemia was done by DMBA in 75 mice. The obtained results were fed into SPSS-22 software and analyzed by one-way ANOVA. By quantitative real-time PCR, S1PR1 and S1PR5 mRNA expression in lymphocytes were significantly (p ≤ 0.01) increased by treating the leukemic mice with the AgNPs and mitoxantrone. Also, AgNPs similar to mitoxantrone, significantly (p ≤ 0.01) enhanced the platelet, lymphocyte, and RBC parameters and the anti-inflammatory cytokines (IL4, IL5, IL10, IL13, and IFNα) and reduced the total WBC, blast, monocyte, neutrophil, eosinophil, and basophil counts and the pro-inflammatory cytokines (IL1, IL6, IL12, IL18, IFNY, and TNFα) as compared to the untreated mice. In vitro experiment, AgNPs similar to mitoxantrone had low cell viability dose-dependently against murine C1498, human HL-60/vcr, and 32D-FLT3-ITD cell lines without any cytotoxicity on HUVEC cell line. Furthermore, the DPPH assay showed similar antioxidant potentials for AgNPs and mitoxantrone. Above results approve the excellent anti-acute myeloid leukemia, cytotoxicity, and antioxidant properties of AgNPs compared to mitoxantrone. 相似文献
109.
110.
Overoxidized polypyrrole (OPPy) films templated with salicylate (SA) have been utilized as conducting molecular imprinted polymers (CMIPs) for potential-induced selective solid-phase micro-extraction processes. Various important fabrication factors for controlling the performance of the OPPy films have been investigated using fluorescence spectrometry. Several key parameters such as applied potential for uptake, release, pH of uptake and release solution were varied to achieve the optimum micro-extraction procedure. The film template with SA exhibited excellent selectivity over some interference. The calibration graphs were linear in the ranges of 5×10(-8) to 5×10(-4) and 1.2×10(-6) to 5×10(-4)mol mL(-1) and the detection limit was 4×10(-8) mol L(-1). The OPPy film as the solid-phase micro-extraction absorbent has been applied for the selective clean-up and quantification of trace amounts of SA from physiological samples. The results of scanning electron microscopy (SEM) have confirmed the nano-structure morphologies of the films. 相似文献