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101.
Srishti Shukla Dommati Anand Kumar Sanga Venkata Anusha 《Natural product research》2016,30(5):583-589
Effect of aqueous methanol extract of different colour sweet bell peppers (Capsicum annuum L.) on parameters of diabesity and carbonyl stress was analysed in vitro. Yellow pepper displayed significantly (p < 0.001) higher intestinal α-glucosidase inhibitory activity than green and red pepper. Porcine pancreatic lipase inhibitory activity was significantly (p < 0.01) high in yellow and red pepper than in green pepper. Green and red pepper inhibited vesperlysine-type advanced glycation end products (AGEs) more potently than yellow pepper; however, pentosidine-type AGEs were similarly inhibited by all three peppers. Yellow and red pepper inhibited lipid peroxidation more potently (p < 0.01) than green pepper. Total polyphenol content and free radicals scavenging activities in yellow and red bell peppers were higher than in green pepper. Total flavonoid content was high in green pepper than that present in yellow and red peppers. Green pepper displayed presence of proanthocyanins; however, oligomeric anthocyanins were detected in yellow and red peppers. 相似文献
102.
103.
Some new oscillation and nonoscillation criteria are given for linear delay or advanced differential equations with variable coefficients and not (necessarily) constant delays or advanced arguments. Moreover, some new results on the existence and the nonexistence of positive solutions for linear integrodifferential equations are obtained. 相似文献
104.
Yingtan Yu Ying Lyu Ting Zhang Lin Liu Bing Fan Jian Wang Chaoxing Zhang 《Molecules (Basel, Switzerland)》2021,26(21)
Iopromide (IOP), an iodinated X-ray contrast medium (ICM), is identified as a precursor to iodide disinfection byproducts that have high genotoxicity and cytotoxicity to mammals. ICM remains persistent through typical wastewater treatment processes and even through some hydroxyl radical-based advanced oxidation processes. The development of new technologies to remove ICMs is needed. In this work, mackinawite (FeS)-activated sulfite autoxidation was employed for the degradation of IOP-containing water. The experiment was performed in a 500 mL self-made temperature-controlled reactor with online monitoring pH and dissolved oxygen in the laboratory. The effects of various parameters, such as initial pH values, sulfite dosages, FeS dosages, dissolved oxygen, and inorganic anions on the performance of the treatment process have been investigated. Eighty percent of IOP could be degraded in 15 min with 1 g L−1 FeS, 400 μmol L−1 sulfite at pH 8, and high efficiency on the removal of total organic carbon (TOC) was achieved, which is 71.8% via a reaction for 1 h. The generated hydroxyl and oxysulfur radicals, which contributed to the oxidation process, were identified through radical quenching experiments. The dissolved oxygen was essential for the degradation of IOP. The presence of Cl− could facilitate IOP degradation, while NO3− and CO32− could inhibit the degradation process. The reaction pathway involving H-abstraction and oxidative decarboxylation was proposed, based on product identification. The current system shows good applicability for the degradation of IOP and may help in developing a new approach for the treatment of ICM-containing water. 相似文献
105.
Z. F. Zhou H. Huang N. C. Liu 《Journal of polymer science. Part A, Polymer chemistry》2001,39(4):486-494
The graft copolymerization of undecylenic acid onto acrylonitrile–butadiene–styrene terpolymer (ABS) was initiated with benzoyl peroxide (BPO) in a 1,2‐dichloroethane solution. IR spectra confirmed that undecylenic acid was successfully grafted onto the ABS backbone. The influence of the concentrations of undecylenic acid, BPO, and ABS on the graft copolymerization was studied. A reaction mechanism was proposed: the grafting most likely took place through the addition of poly(undecylenic acid) radicals to the double bond of the butadiene region of ABS. A monomer cage effect on the graft reaction was observed to depend on the 1.5 power of the monomer concentration from the experimental results of the initial rate of graft copolymerization. The initial rate of graft copolymerization was written as Rp = 1.77 × 10−3[P][I2][M]2.5/([P]+2.75[M]2.5)2. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 486–494, 2001 相似文献
106.
以ABS塑料为研究对象,采用微波消解法进行样品的前处理,使用电感耦合等离子体发射光谱法测定ABS塑料中Pb、Cd、Hg,结果表明,Pb、Cd、Hg加标回收率均在95~105%之间,测试精密度均小于3%,该方法在缩短样品前处理时间的同时得到较高的元素消解回收率和较为理想的精确度,适用于ABS塑料中重金属含量的快速测定。 相似文献
107.
Klaudia Stando Patrycja Kasprzyk Ewa Felis Sylwia Bajkacz 《Molecules (Basel, Switzerland)》2021,26(24)
Metronidazole (MET) is a commonly detected contaminant in the environment. The compound is classified as poorly biodegradable and highly soluble in water. Heterogeneous photocatalysis is the most promoted water purification method due to the possibility of using sunlight and small amounts of a catalyst needed for the process. The aim of this study was to select conditions for photocatalytic removal of metronidazole from aquatic samples. The effect of catalyst type, mass, and irradiance intensity on the efficiency of metronidazole removal was determined. For this purpose, TiO2, ZnO, ZrO2, WO3, PbS, and their mixtures in a mass ratio of 1:1 were used. In this study, the transformation products formed were identified, and the mineralization degree of compound was determined. The efficiency of metronidazole removal depending on the type of catalyst was in the range of 50–95%. The highest MET conversion (95%) combined with a high degree of mineralization (70.3%) was obtained by using a mixture of 12.5 g TiO2–P25 + PbS (1:1; v/v) and running the process for 60 min at an irradiance of 1000 W m−2. Four MET degradation products were identified by untargeted analysis, formed by the rearrangement of the metronidazole and the C-C bond breaking. 相似文献
108.
20世纪80年代至今,水处理技术中的高级氧化过程(AOP)已被广泛研究及应用。然而水体中的有机污染物仍因种类繁多和降解难易不同困扰着研究者们,因此对于AOP的机理过程需要更深入的分析认识,以利于技术的进一步发展及应用。AOP中的过硫酸盐氧化工艺近年来得到大量关注,其自由基机理的关键活性物种是·OH 和·SO4-。非自由基机理分为1O2氧化和PS直接氧化(也称电子转移),某些体系中高价态金属也直接或间接地参与氧化过程。但非自由基过程的发生机理及优势特点仍存在争议。本文综述了基于多相催化过硫酸盐高级氧化过程处理水中有机污染物的最新研究,阐述反应机理及其分析手段,并指出当前研究可能存在的问题。对于过硫酸盐高级氧化工艺中非自由基过程的未来研究方向及应用前景提出展望。 相似文献
109.
We derive rational solutions in Casoratian form for the Nijhoff-Quispel-Capel (NQC) equation by using the lattice potential Korteweg-de Vries (lpKdV) equation and two Miura transformations between the lpKdV and the lattice potential modified KdV (lpmKdV) and the NQC equation. This allows us to present rational solutions for the whole Adler-Bobenko-Suris (ABS) list except Q4. The known Miura transformation for soliton solutions between the NQC equation and Q3δ and the known degenerations for solitons from Q3δ to Q2, Q1δ, H3δ, H2 and H1 in the ABS list are used. We show that the Miura transformation and degenerations are valid as well for rational solutions which are usually considered as “long-wave-limit” of solitons. All the rational solutions can be expressed in terms of {z j} which are linear functions of (n, m). 相似文献
110.