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排序方式: 共有390条查询结果,搜索用时 15 毫秒
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Polyethersulfone was sulfonated by changing the reaction time with sulfuric acid. The degree of sulfonation and ion exchange capacity were determined. Sulfonation of polyethersulfone was confirmed by FT-IR analysis and a new peak at 1025 cm?1. Inorganic materials such as carbon nanotubes, graphene, and kaolinite nanoparticles were synthesized. The effects of three nanoparticles on thermal stability and water uptake of sulfonated polyethersulfone were investigated. The morphology of membranes were also altered due to the addition of inorganic materials. The proton conductivity of the modified membranes increased with respect to increase in relative humidity. 相似文献
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B. M. Praveen T. V. Venkatesha K. G. Chandrappa S. E. Nataraja M. K. Punith Kumara S. Ranganatha C. M. Praveen Kumar P. Sarala M. K. Pavithra 《Transactions of the Indian Institute of Metals》2012,65(3):297-302
The inhibition behavior of metol (N-methyl-p-aminophenol sulphate) on zinc in different corrosive solutions at room temperature was investigated by various techniques such as weight loss, polarization and linear polarization methods. The percentage inhibition efficiencies were evaluated at different concentrations of the inhibitors. The corrosion rate, inhibition efficiency and surface coverage were dependent on metol concentration. The electrochemical data indicated a basic modification of zinc surface resulting in a decrease in the corrosion rate. Corrosion inhibition was explained by considering an interaction between metal surface and the inhibitor. SEM images and FT-IR profiles confirmed the formation of passive film on the metal surface. 相似文献
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让周遭的系统能够自动感测环境变化并做出反应,势必将对于人类的生活造成重大改变。无线传感器网络是多个分布式传感器实作(节点)组成的系统,能够共同透过相互无线通信的方式响应实体变化。本文将重点介绍节点的最新进展,并推广对于系统层级设计方法的需求。 相似文献
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Sudhan A. L. Sriram Solomon A. Brusly Immanuel I. Darwin 《Journal of Mechanical Science and Technology》2021,35(11):5213-5223
Journal of Mechanical Science and Technology - A comparative heat transfer performance of an internally grooved anodized thermosyphon with eco-friendly refrigerants is presented in this study.... 相似文献
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G. Britto Joseph G. NarendraKumar G. Mageshwaran Jeya Jeevahan V. Sriram R. B. Durai Raj 《国际自然能源杂志》2013,34(8):863-867
Nowadays, refrigeration systems are important for industrial and domestic applications. The coefficient of performance of a vapour compression refrigeration system can be improved if a reduction in the work of compression can be achieved by a suitable technique for a specified heat removal rate. The present study investigates the effect of material coating of electroless nickel (EN) plating. The friction and wear experiments were performed using a four-ball machine tribo tester. Controlling the EN plating parameters plays an important role in the quality of coating. It depends on the wear scar rate of the coated material. So it is necessary to optimise the process parameters of EN plating. The experimental studies have been conducted under varying pressure, load and time on quality characteristics. In this paper, optimisation of process parameters using response surface methodology technique for EN plating was discussed. 相似文献
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Pavithra Shyamsunder Shree Pooja Sridharan Vikas Madan Pushkar Dakle Cao Zeya Deepika Kanojia Wee-Joo Chng S. Tiong Ong H. Phillip Koeffler 《International journal of molecular sciences》2022,23(3)
Multiple myeloma (MM) is a hematological disease marked by abnormal growth of B cells in bone marrow. Inherent chromosomal instability and DNA damage are major hallmarks of MM, which implicates an aberrant DNA repair mechanism. Studies have implicated a role for CDK12 in the control of expression of DNA damage response genes. In this study, we examined the effect of a small molecule inhibitor of CDK12–THZ531 on MM cells. Treatment of MM cells with THZ531 led to heightened cell death accompanied by an extensive effect on gene expression changes. In particular, we observed downregulation of genes involved in DNA repair pathways. With this insight, we extended our study to identify synthetic lethal mechanisms that could be exploited for the treatment of MM cells. Combination of THZ531 with either DNA-PK inhibitor (KU-0060648) or PARP inhibitor (Olaparib) led to synergistic cell death. In addition, combination treatment of THZ531 with Olaparib significantly reduced tumor burden in animal models. Our findings suggest that using a CDK12 inhibitor in combination with other DNA repair inhibitors may establish an effective therapeutic regimen to benefit myeloma patients. 相似文献
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Response surface methodology (RSM) based on a D-optimal design was employed to investigate the tribological characteristics of journal bearing materials such as brass, bronze, and copper lubricated by a biolubricant, chemically modified rapeseed oil (CMRO). The wear and friction performance were observed for the bearing materials tested with TiO2, WS2, and CuO nanoadditives dispersed in the CMRO. The tests were performed by selecting sliding speed and load as numerical factors and nano-based biolubricant/bearing materials as the categorical factor to evaluate the tribological characteristics such as the coefficient of friction (COF) and specific wear rate. The results showed that RSM based on a D-optimal design was instrumental in the selection of suitable journal bearing materials for a typical system, especially one lubricated by nano-based biolubricant. At a sliding speed of 2.0 m/s and load of 100 N, the bronze bearing material with CMRO containing CuO nanoparticles had the lowest COF and wear rate. In addition, scanning electron microscopy (SEM) examination of the worn bearing surfaces showed that the bronze bearing material lubricated with CMRO containing CuO nanoadditive is smoother than copper/brass bearing material. 相似文献