Green tea polyphenol-reduced graphene oxide: derivatisation, reduction efficiency, reduction mechanism and cytotoxicity

This paper reports on the derivatisation, reduction efficiency, reduction mechanism and cytotoxicity of green tea polyphenol-reduced graphene oxide (GTP-RGO). The reduction of graphene oxide (GO) at 90°C using a weight ratio (WR) of GTP/GO=1 resulted in the production of a stable GTP-RGO dispersion in aqueous media, as indicated by the results of ultravioletvisible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and the measurement of zeta potential and electrophoretic mobility. In addition, the results from UV-Vis spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis indicated the comparable reduction ability of GTP relative to the standard reducing agent, hydrazine (N2H4). The removal mechanism of epoxy group from GO via reduction reaction with GTP was investigated by implementing hybrid functional method of Becke-3-parameters-Lee-Yang-Parr (B3LYP)using Gaussian 09 software. The energy and frequency calculations showed that the GO reduction using GTP was more spontaneous and relatively took place faster than the reduction using N2H4, as evidenced by higher entropy change (ΔS) (0.039 kcal/mol·K) and lower Gibbs free energy (ΔG) barrier (58.880 kcal/mol).The cytotoxicities of GO and GTP-RGO samples were evaluated against human colonic fibroblasts cells (CCD-18Co). The GO sample was determined to be toxic even at low concentration (6.25 μg/mL), while the GTP-RGO sample possesses notably low toxicity at the same concentration. The cell culture experiments revealed that the incorporation of GTP led to a decrease in the toxicity of GTP-RGO samples

A mission synthesis algorithm for fatigue damage analysis

This paper presents a signal processing based algorithm, the Mildly Nonstationary Mission Synthesis (MNMS), which produces a short mission signal from long records of experimental data. The algorithm uses the Discrete Fourier Transform, Orthogonal Wavelet Transform and bump reinsertion procedures. In order to observe the algorithm effectiveness a fatigue damage case study was performed for a vehicle lower suspension arm using signals containing tensile and compressive preloading. The mission synthesis results were compared to the original road data in terms of both the global signal statistics and the fatigue damage variation as a function of compression ratio. Three bump reinsertion methods were used and evaluated. The methods differed in the manner in which bumps (shock events) from different wavelet groups (frequency bands) were synchronised during the reinsertion process. One method, based on time synchronised section reinsertion, produced the best results in terms of mission signal kurtosis, crest factor, root-mean-square level and power spectral density. For improved algorithm performance, bump selection was identified as the main control parameter requiring optimisation

Peranan Pembiyaan Murabahah dalam Pengembangan Usaha pada PT Bank Muamalat

The purpose of this study to determine how the role of murabahah financing in developing the business at PT. Bank Muamalat Branch Baubau Assistant. The population in this study is 268 number of customers in Murabahah Financing At PT. Bank Muamalat Branch Baubau Assistant. The method used is descriptive method of collecting data obtained and then interpret and analyze it so as to provide information that can be used to solve problems encountered. The data used are primary data and secondary data. This research concludes that the role of murabahah financing product in BMI has applied financing principle in accordance with Fatma Dewan Syariah Nasional. 04 / DSN MUI / IV / 2000. About Murabahah in every financing transaction by paying attention to contract, sale price, financing requirement, term of financing, way of mortgage financing, and also pay attention to murabahah financing role at bank muamalat. The authors suggest that PDD BIM should improve professionally delivered, in terms of products, services, and implementation in accordance with sharia principles

Pembelajaran dalam Perspektif Kreativitas Guru dalam Pemanfaatan Media Pembelajaran

Learning will work well without using media appropriate to the material to be taught, because apart from being an intermediary media is also useful to overcome the limitations of space, time, and power the senses, such as an object that is too large can be replaced with reality, image, or movie frame , In use in the learning process, the teacher must know and master as well as capable of using media in teaching and learning. This capability is an imaginative activity that result is the formation of a combination of information obtained from previous experiences into new, meaningful and useful. So therefore, the creativity of teachers in the use of instructional media can be concluded, namely: (1) The creativity of teachers in the use of instructional media in learning a subject usually, only teachers use media such as books, whiteboard and markers. The success of the learning process depends on the competence of teachers in mastering the material or subject matter. Schools seek help improve the facilities and means associated with school education in one facility and related instructional media to increase student achievement and quality of education in schools