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1.
The synergistic interactions and corrosion protection properties of 2-amino 4-methyl benzothiazole, (AMBT) and 1, 2, 3-benzotriazole (BTZ) have been studied for mild steel in HCl at elevated temperatures. The extent of synergistic interaction increases with temperature. The methods of study include the conventional weight loss studies, computational screening, surface characterization and electrochemical studies. Quantum chemical approach was used to calculate some electronic properties of the molecules and to ascertain the synergistic interaction, inhibitive effect and molecular structures. The corrosion inhibition efficiencies and the global chemical reactivity relate to parameters like total energy, EHOMO, ELUMO and gap energy (ΔE). Condensed atom Fukui functions also calculated using DFT at B3LYP/6-31G* level, and were found to be correlating with the experimental results.  相似文献   
2.
A study on the “Biochemical changes in groundnut pods due to infestation of bruchid, Caryedon serratus (Olivier) under stored conditions” was conducted at Department of Entomology, College of Agriculture, SVPUA&T, Meerut during August 2018 to February 2019. Results of the study showed that there was significant increase in weight loss of the groundnut pods (test varieties) with the increase in storage period i.e. 30, 90, and 150 DAS (days after storage). This significant increase in weight loss was due to infestation of groundnut bruchid. In addition to the weight loss, distinct differences in the biochemical components such as sugars, proteins, tannins, phenols were found in between infested and uninfested groundnut pods. A significant reduction in sugars, tannins, phenol whereas increase in protein content was noticed with the increase in the storage period i.e. 30, 90 and 150 DAS. Correlation studies relating weight loss and biochemical components from different groundnut varieties (resistant and susceptible) due to bruchid infestation were also worked out in the study. Pod sugar and pod protein content showed significant positive correlation with weight loss (positive effect on the development of the bruchid). While, pod tannins and pod phenols content showed significant negative correlation with weight loss (exerted a negative effect on the development of the bruchid).  相似文献   
3.
For many-objective optimization problems, how to get a set of solutions with good convergence and diversity is a difficult and challenging work. In this paper, a new decomposition based evolutionary algorithm with uniform designs is proposed to achieve the goal. The proposed algorithm adopts the uniform design method to set the weight vectors which are uniformly distributed over the design space, and the size of the weight vectors neither increases nonlinearly with the number of objectives nor considers a formulaic setting. A crossover operator based on the uniform design method is constructed to enhance the search capacity of the proposed algorithm. Moreover, in order to improve the convergence performance of the algorithm, a sub-population strategy is used to optimize each sub-problem. Comparing with some efficient state-of-the-art algorithms, e.g., NSGAII-CE, MOEA/D and HypE, on six benchmark functions, the proposed algorithm is able to find a set of solutions with better diversity and convergence.  相似文献   
4.
本文讨论了水质污染评价中,模糊变换■三种数学模型的应用问题。这三种数学模型为:■当在模糊变换中使用了权重向量(?)时,应选用数学模型3。本文最后讨论了综合评价目的向量■的应用问题。  相似文献   
5.
层状粘弹性地基动力响应的样条半解析法   总被引:2,自引:1,他引:2       下载免费PDF全文
提出应用样条半解析法求解层状粘弹性地基的动力响应。首先将位移函数表示为一次样条函数与Fourier级数的乘积形式 ,并使其满足无穷远处的边界条件 ,根据复阻尼理论的拉格朗日方程 ,使问题归结为求解若干次低阶复代数方程。在此基础上求解了落锤式弯沉仪 (FWD)所记录的荷载作用下的层状粘弹性地基动力响应。数值结果表明 ,该方法具有较高的精度。从而为落锤式弯沉仪 (FWD)检测路面提供了理论基础。  相似文献   
6.
Compared to the traditional one-by-one method, a new high-efficiency method is used to characterize large numbers of regulations varying samples.Accordingly, bump-shaped electrodes are designed using the computational fluid dynamics model, and the effect of the height and placement of these electrodes is discussed.The experimental feasibility is certified by weight loss measurement.Results indicate that flow velocities of different bump-shaped electrode surfaces are significant differences.Thus, each surface can be analyzed independently; the thickness loss of each electrode surface is consistent with that using one-by-one method, which can effectively improve the experimental efficiency 12 times.  相似文献   
7.
简述一种液压驱动型可穿戴式负重外骨骼的整体结构设计;建立多目标优化模型,以膝关节液压缸受力最小和质量最小为目标,运用多目标优化方法中的线性加权和法对其进行优化处理,化多目标优化问题为单目标优化问题;分别利用MATLAB中的fmincon函数和遗传算法对该模型进行优化,使得液压缸的受力值和质量都大大降低,为负重外骨骼驱动系统节约了能耗,延长了使用寿命。  相似文献   
8.
简要回顾了汽车前端框架设计方案轻量化的演变历史,基于前端框架设计指标、虚拟仿真和材料方案三个方面轻量化现状的详细描述,论证了前端框架日趋精益轻量化的趋势。  相似文献   
9.
The fuzzy logical relationships and the midpoints of interval have been used to determine the numerical in-out-samples forecast in the fuzzy time series modeling. However, the absolute percentage error is still yet significantly improved. This can be done where the linguistics time series values should be forecasted in the beginning before the numerical forecasted values obtained. This paper introduces the new approach in determining the linguistic out-sample forecast by using the index numbers of linguistics approach. Moreover, the weights of fuzzy logical relationships are also suggested to compensate the presence of bias in the forecasting. The daily load data from National Electricity Board (TNB) of Malaysia is used as an empirical study and the reliability of the proposed approach is compared with the approach proposed by Yu. The result indicates that the mean absolute percentage error (MAPE) of the proposed approach is smaller than that as proposed by Yu. By using this approach the linguistics time series forecasting and the numerical time series forecasting can be resolved.  相似文献   
10.
Vegetable oils and biodiesel have emerged as strong alternative fuels worldwide. However use of new fuels in existing engines leads to issues such as wear of vital moving components, and fuel injection equipment (FIE). It is important to ensure that new alternative fuel does not affect the FIE adversely. In this experimental study, a non-firing engine FIE simulator test rig prototype was developed and 250 h endurance test of FIE was performed with an objective to ensure the long-term compatibility and durability of biofuel blends. The components of FIE such as plunger, nozzle needle, valve, and valve holder were investigated for wear. Test fuels used in this study were Karanja blends (K20, K5), Jatropha blends (J20, J5), Biodiesel blends (B20, B5) and baseline mineral diesel in a non-firing engine FIE simulator. The compatibility of FIE with test fuels in terms of dimensional loss, weight loss and surface texture variations using optical microscopy before and after the endurance test was compared. Biodiesel blends showed relatively lower wear compared to mineral diesel however SVO blends showed no definite trend of the wear results compared to baseline mineral diesel.  相似文献   
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