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111.
《Journal of Saudi Chemical Society》2022,26(4):101488
Increase in the number of infections caused by pathogenic microbes in cancer patients has prompted the searcher to invest in the development of agents having dual anticancer and antimicrobial properties. The present study is concerned with synthesis and screening for anticancer and antimicrobial activity of a series of 5-hydrazinyl-2-(2-(1-(thien-2-yl)ethylidene)hydrazinyl)thiazole derivatives. The structure elucidation of the synthesized hydrazinyl thiazole derivatives was illustrated by spectroscopic and elemental analysis. All the newly synthesized compounds 5a-p were evaluated for in-vitro cytotoxic activity against breast carcinoma (MCF-7 cell line), hepatocellular carcinoma (HePG-2) and colorectal cancer (HCT-116) cell lines using MTT assay method. Compounds 5 g, 5h showed broad spectrum activity against three cancer cell lines with IC50 ranged from 3.81 to 11.34 µM in compared to the reference drug Roscovitine (IC50 = 9.32 to 13.82 µM), while compounds 5 l and 5 m were found to be more selective against HePG-2 and HCT-116 cell line (IC50 = 9.29 and 8.93 µM respectively) and compound 5j was more selective against HePG-2 and MCF-7 cell lines (IC50 = 6.73 and 10.87 µM respectively). The inhibitory activity of the most promising compounds was tested against the EGFR and ARO enzymes and were further tested for apoptosis and Annexin V/PI staining. The results of enzyme-based tests revealed that the tested compound 5j has a dual inhibitory effect on the EGFR and ARO enzymes with IC50 = 82.8 and 98.6 nM respectively in compared to the reference drugs Erlotinib and Letrozole (IC50 = 62.4 and 79 nM respectively). Furthermore, the majority of the tested hydrazinyl thiazole derivatives exhibited significant antimicrobial activity against the used pathogenic microbes species. Compounds 4b, 5h, 5j and 5 m exerted a good antibacterial and antifungal activity against all tested pathogenic microbes. Therefore, it was concluded that compounds 5 h, 5j and 5 m proved to possess dual anticancer and antimicrobial agent and may serves as a useful lead compounds in search for further modification or derivatization to give more potent and selective agents. 相似文献
112.
摩托车传动用滚子链磨损特性的研究 总被引:5,自引:1,他引:5
道路行驶磨损试验结果表明,摩托车传动用滚子链套筒和销轴零件的主要磨损形式是磨粒磨损,并伴随有疲劳磨损的特征.由微观分析和链条的磨损伸长量可知:套筒和销轴的初始表面硬度较高,有利于改善其磨损表面形貌状态和耐磨性;在磨粒磨损机制下,套筒和销轴零件的表面硬度较低,容易产生“犁切”,表面层的循环硬化现象比较明显,磨损严重;在油池润滑条件下,套筒和销轴零件的表面硬度较高,裂纹的扩展速率较快,循环软化现象也较明显,当表面硬度较低时发生循环硬化.循环软化与循环硬化是导致磨损严重的原因之一. 相似文献
113.
应用基于压电超声疲劳试验技术开发的20kHz轴向振动疲劳试验系统,完成了室温下TC4钛合金超高周疲劳试验,获得了TC4合金在107~109周次范围内的轴向振动疲劳寿命曲线(S-N曲线);运用C.Paris推导公式预测了TC4合金材料的寿命,得到各应力水平下破坏率为50%、95%、99%的安全寿命.结果表明:在疲劳循环大于107周次时,试件仍会发生疲劳断裂,疲劳强度随循环次数的增加而下降,并不存在明显的疲劳极限.TC4合金的S-N曲线在107~109周次的范围内呈连续下降型.在轴向振动超高周疲劳试验中,试件的裂纹扩展寿命只占其在50%破坏率下疲劳安全寿命的一小部分,其疲劳寿命主要由试件的裂纹萌生寿命决定. 相似文献
114.
Saeed Khojaste Effatpanah Mohammad Hossein Ahmadi Seyed Hamid Delbari Giulio Lorenzini 《Entropy (Basel, Switzerland)》2022,24(2)
In recent decades, there has been an increasing trend toward the technical development of efficient energy system assessment tools owing to the growing energy demand and subsequent greenhouse gas emissions. Accordingly, in this paper, a comprehensive emergy-based exergoeconomic (emergoeconomic) method has been developed to study the biomass combustion waste heat recovery organic Rankine cycle (BCWHR-ORC), taking into account thermodynamics, economics, and sustainability aspects. To this end, the system was formulated in Engineering Equation Solver (EES) software, and then the exergy, exergoeconomic, and emergoeconomic analyses were conducted accordingly. The exergy analysis results revealed that the evaporator unit with 55.05 kilowatts and the turbine with 89.57% had the highest exergy destruction rate and exergy efficiency, respectively. Based on the exergoeconomic analysis, the cost per exergy unit , and the cost rate of the output power of the system were calculated to be 24.13 USD/GJ and 14.19 USD/h, respectively. Next, by applying the emergoeconomic approach, the monetary emergy content of the system components and the flows were calculated to evaluate the system’s sustainability. Accordingly, the turbine was found to have the highest monetary emergy rate of capital investment, equal to , and an output power monetary emergy of . Finally, a sensitivity analysis was performed to investigate the system’s overall performance characteristics from an exergoeconomic perspective, regarding the changes in the transformation coefficients (specific monetary emergy). 相似文献
115.
116.
当一种突发传染病开始流行时,政府、媒体会以各种形式告知民众,有防范意识的民众将采取一定的防范措施来降低感染率.考虑面对一种突发传染病,将易感群体划分为具有防范意识和不具有防范意识两种群体,利用生命周期理论,分析网络媒体信息报道对传染病传播的影响,以此为依据建立一种改进的传染病传播模型(MSI).利用网络大数据得到对传染病有防范意识群体的观测值信息,利用神经网络技术对模型MSI的参数进行反演.然后对模型MSI数值仿真得到传染病传播过程,提出了相应的控制措施. 相似文献
117.
Tony Huynh Andrew D. King Sang‐il Oum Maryam Verdian‐Rizi 《Journal of Graph Theory》2017,84(2):158-175
A graph is strongly even‐cycle decomposable if the edge set of every subdivision with an even number of edges can be partitioned into cycles of even length. We prove that several fundamental composition operations that preserve the property of being Eulerian also yield strongly even‐cycle decomposable graphs. As an easy application of our theorems, we give an exact characterization of the set of strongly even‐cycle decomposable cographs. 相似文献
118.
An m-cycle system of order ν and index λ, denoted by rn-CS(ν, λ), is a collection of cycles of length m whose edges partition the edges of λκ_v. An m-CS(ν, λ) is α-resolvable if its cycles can be partitioned into classes such that each point of the design occurs in precisely α cycles in each class. The necessary conditions for the existence of such a design are m|λν(ν-1)/2,2|λ(ν-1), m|αν,α|λ(ν-1)/2 It is shown in this paper that these conditions are also sufficient when m = 4. 相似文献
119.
In this paper, we study the explicit expansion of the first order Melnikov function near a double homoclinic loop passing through a nilpotent saddle of order m in a near-Hamiltonian system. For any positive integer , we derive the formulas of the coefficients in the expansion, which can be used to study the limit cycle bifurcations for near-Hamiltonian systems. In particular, for , we use the coefficients to consider the limit cycle bifurcations of general near-Hamiltonian systems and give the existence conditions for 10, 11, 13, 15 and 16 (11, 13 and 16, respectively) limit cycles in the case that the homoclinic loop is of cuspidal type (smooth type, respectively) and their distributions. As an application, we consider a near-Hamiltonian system with a nilpotent saddle of order 2 and obtain the lower bounds of the maximal number of limit cycles. 相似文献
120.
结合5种混凝土延性柱耗能器在低周期反复荷载作用下的试验数据研究,利用神经网络的工作原理,通过建立神经网络的输入层、隐含层、输出层,确定输入单元、输出单元和隐含层节点数,从而建立了BP神经网络的模型,并根据已有的部分试验数据数据.对网络进行训练,对各种混凝土延性柱耗能器骨架曲线进行了预测拟合,实现混凝土延性柱耗能器骨架曲线的数字化,使其成为具有分析和判断的拟合曲线功能,完整的描绘混凝土延性柱耗能器的骨架曲线,为后续混凝土延性柱耗能器性能研究的仿真模拟提供了可靠的数据模型.结果表明,这种方法是可行的. 相似文献