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901.
以天然产物α蒎烯为原料,经多步反应合成了9个新型α-蒎烯基苯磺酰胺类化合物(7a~7i),其结构经1H NMR、 13C NMR、 FT-IR和MS(ESI)表征。采用离体法测试了化合物的抗真菌活性。结果表明:在50 μg·mL-1浓度下,目标化合物对黄瓜枯萎病菌、花生褐斑病菌、苹果轮纹病菌、小麦赤霉病菌以及番茄早疫病菌等5种植物病原菌有一定的抑制活性,其中化合物α-蒎烯基p-氯苯基磺酰胺(7d, R=p-Cl)和α-蒎烯基o-硝基苯基磺酰胺(7h, R=o-NO2)对苹果轮纹病菌的抑制率分别为83.9%和79.6%(B级活性水平),优于阳性对照百菌清(75.0%);化合物α-蒎烯基m-甲基苯基磺酰胺(7b, R=m-Me)对番茄早疫病菌的抑制率为82.2%(B级活性水平),优于阳性对照百菌清(73.9%)。- 相似文献
902.
采用乙醇浸提法来提取地锦草中的有效成分,并对其生物活性进行研究。探讨了地锦草总黄酮的最佳提取工艺;通过体外抗氧化实验,对地锦草提取物的抗氧化活性进行研究;同时考察了提取物对大肠杆菌、枯草芽孢杆菌、青霉、曲霉的抗菌性能,并对地锦草提取物对α-淀粉酶的抑制活性进行研究。实验结果表明:地锦草总黄酮最佳提取工艺为乙醇体积分数为85%,料液比为1∶15,提取次数为3次;体外抗氧化实验表明,地锦草具有抗氧化活性,且在浓度为8 mg/mL最为明显;抗菌性能实验表明,地锦草具有抗菌性能,且对青霉、曲霉的抗菌效果比较显著;α-淀粉酶的抑制活性的实验表明,地锦草提取物对α-淀粉酶的活性有抑制能力,在pH 6.8、浓度为4.8 mg/mL、温度为70℃时,其对α-淀粉酶的抑制效果达到最大。 相似文献
903.
Guangjian WANG Hao XU Kai LU Zhihao DING Liancheng BING 《Turkish Journal of Chemistry》2020,44(1):112
Vanadium oxides, as highly efficiently catalysts, are widely applied in various catalytic reactions, such as the dehydrogenation of light alkanes and epoxidation of alkenes. In this paper, a series of VO x /Al 2 O 3 catalysts were fabricated by the 1-pot method for catalytic propane dehydrogenation. The results indicated that the VO x /Al 2 O 3 catalysts with loading of 10 wt.% vanadium exhibited optimized catalytic performance. The as-prepared catalysts were characterized by N 2 adsorption-desorption, XRD, TEM, H 2 -TPR, and XPS to explore the texture properties, morphology, and electronic environment of vanadium. In addition, several vanadium catalysts were also prepared by the incipient wetness impregnation (IWI) method to compare their catalytic performance with the 1-pot synthesized catalysts. The catalysts synthesized by the 1-pot method exhibited higher selectivity of propylene and longer catalyst lifetime at high propane conversion when compared to the counterpart synthesized by the IWI method. 相似文献
904.
Bünyemin OUT Burcu TOPALOLU AKSOY Süreyya Ouz TÜMAY Ahmet ENOCAK Serkan YELOT 《Turkish Journal of Chemistry》2020,44(1):48
Phenoxy- and naphthoxy-substituted bisphenol-bridged cyclic phosphazenes were synthesized in 2 steps and their thermal, photophysical, and electrochemical properties were investigated. The structures of the cyclic phosphazene compounds were determined by ESI-MS mass spectrometry and 1 H, 13 C, and 31 P NMR spectroscopies. The photophysical studies of phenoxy- and naphthoxy-substituted bridged cyclophosphazenes were investigated by means of absorption and fluorescence spectroscopies in different solvents. Thermal and electrochemical properties of the target compounds were also studied. Furthermore, the excimer emissions through intramolecular interactions in solution and in solid state were investigated by fluorescence spectroscopy and the theoretical calculations were performed in detail using DFT. 相似文献
905.
In this study, nanofiber structures were obtained with convenient polymers (PVA [polyvinyl alcohol] and PCL [poly o-caprolactone]) derived from the herbal extracts of olive leaves, fumitory, and terebinth plants. Optimum nanofiber structures were identified by measuring viscosity and conductivity values and performing morphological analysis, characterization, and mechanical tests of the prepared solutions. The potential use for wound healing at the most efficient level was determined as a result of antibacterial analysis of the structures obtained. APT (PVA/terebinth) and BFO (PCL/fumitory) nanofibers had the thinnest diameter range and the highest strength values. In terms of the determination of antibacterial effects, nanofiber structures of all 3 plant species proved to be effective against bacteria. The greatest effect was observed against Escherichia coli in the nanofiber structure containing olive leaves, with a zone diameter of 32 mm. In addition, APT and BFO nanofibers had the highest values of thinness and strength. In these 2 samples, using BFO against Staphylococcus aureus and APT against Candida albicans increased their areas of activity. In the literature review, no study was available about obtaining nanofibers, especially from fumitory and terebinth plants. This study aimed to increase knowledge on obtaining nanofiber structures, including various polymers derived from olive leaves, fumitory, and terebinth plants. 相似文献
906.
Armaan GÜNSEL Aye USLUOLU Ahmet Turgut BLGL TOSUN Büra Gülnur ARABACI Meryem Nilüfer YARAIR 《Turkish Journal of Chemistry》2020,44(4):923
This work reports on dyeing of nylon/elastane fabric with water-soluble phthalocyanines ( 1-4 ) bearing quinoline 5-sulfonic acid substituents on the peripheral or nonperipheral positions and determining the antibacterial efficiency of the phthalocyanine compounds and the dyed nylon/elastane fabrics. The light, washing, water, perspiration, and rubbing fastness properties of nylon/elastane fabrics dyed with phthalocyanines were also determined. The results showed that all dyed fabrics showed very good wet fastness values. The lightfastness value of the nylon/elastane fabric dyed with phthalocyanine dye ( 1 ) showed a much better value than the others. Also, the antibacterial efficiencies of the dyed nylon fabrics and the dye compounds were investigated against a gram-negative ( Escherichia coli ) and a grampositive ( Staphylococcus aureus ) bacteria by using disc diffusion method. The results showed that the dyed nylon/elastane fabrics and the compounds exhibited antibacterial activities against both bacteria. 相似文献
907.
shak ERK Gzde KILI Elif
ZTÜRK engül Alpay KARAOLU Nurettin YAYLI 《Turkish Journal of Chemistry》2020,44(6):1655
The volatile components of essential oil (EO), SPME, and SPME of solvent extracts ( n -hexane, methanol, and water) obtained from fresh Serapias orientalis subsp. orientalis ( Soo ) were analyzed by GC-FID/MS. EO of Soo gave 11 compounds in the percentage of 99.97%; capronaldehyde (37.01%), 2-( E )-hexenal (23.19%), and n -nonanal (19.05%) were found to be major constituents. SPME GC-FID/MS analyses of fresh plant and solvent extracts of Soo revealed 7, 12, 7, and 4 compounds within the range of 99.7% to 99.9%. Limonene (76.5%, 41.7%, and 61.3%) was the major compound in SPMEs of the n -hexane and methanol extracts. α -Methoxy- p -cresol (52.9%) was the main component in its water extract. The antimicrobial activity of EO and the solvent extracts of Soo were screened against 9microorganisms. EO showed the best activity against Mycobacterium smegmatis , with 79.5 µg/mL MIC value. The n -hexane, methanol, and water extracts were the most active against the Staphylococcus aureus within the range of 81.25–125.0 µg/mL (MIC). IC 50 values for the lipase enzyme inhibitory activity of EO and solvent extracts ( n -hexane, methanol, and water) were determined to be 59.87 µg/mL, 64.03 µg/mL, 101.91 µg/mL, and 121.24 µg/mL, respectively. 相似文献
908.
水下核爆作用下混凝土重力坝模型破坏试验 总被引:1,自引:0,他引:1
采用落锤冲击模拟水下核爆的一次冲击波对混凝土重力坝的作用.试验遵循弹性-重力联合相似准则,并以冲量相似条件确定冲击摆的质量与悬挂高度.对两种坝体和坝基接触条件,即一种在平滑基底上筑坝,一种在锚固基底上筑坝,开展模型坝的冲击试验,得到模型坝体的动力特性.试验结果表明,坝体破坏模式包括贯穿性断裂、滑移、碎裂、层裂和抛掷等.并初步研究了核爆输入能量和大坝耗散能量之间的平衡关系. 相似文献
909.
一种有利于提高DHCR比例的热轧批量计划编制方法 总被引:1,自引:1,他引:0
针对一体化生产过程中连铸出坯顺序与热轧轧制顺序的协调问题,提出了计划顺序协调因子,并在此基础上建立了有利于提高直接热装(DHCR)比例的热轧批量计划优化模型.模型在满足热轧轧制工艺的基础上充分考虑了铸坯连铸出坯计划与热轧轧制计划的协调.采用改进遗传算法——两交换启发交叉算法对模型进行了求解.最后,针对大批量少品种和小批量多品种两组板坯对某钢厂2250 mm和1580 mm轧线进行了仿真,仿真结果表明模型可以大大减少铸坯因顺序不协调而引起的在进入加热炉前的等待时间,进而提高板坯DHCR比例. 相似文献
910.
为解决算法生成纹理地图时时间耗费量大的问题,提出采用KD-tree算法对数据结构进行划分、减小KNN算法搜索复杂度、提高搜索速度的方法.针对基于纹理基元的分类算法无法准确检测室外某些纹理相似性较高的自然场景,提出加入颜色特征、设置相应权值构建混合模型的方法.实验结果表明,基于KD-tree的KNN算法可缩短分类时间、满足实时性的要求,基于纹理基元与颜色的分类算法在室外自然场景中能够获得较高的分类精确度. 相似文献