International Journal of Nanomanufacturing (5 papers in press)

Regular Issues

• Research on Non-contact Ultrasonic Vibration Assisted Rotating Electrical Discharge Machining?EDM? Machine Tool  
  by Yinghuai Dong, Song Jianbao, Li Guangyan, Wang Yan, Xue Wei 
  Abstract: EDM is a nontraditional machining method by using pulsed spark discharge between workpiece and electrode to melt and remove metal. The traditional power supply method uses carbon brush and slip ring. This contact type has power supply at the contact point. Problems such as carbon deposition, leakage, and easy generation of electric sparks restrict the improvement of the rotation speed of the electrode and pose a safety hazard. The non-contact power supply technology based on the principle of electromagnetic induction can effectively solve the above problems, which can provide conditions for high-speed rotation of the electrode. In order to improve the processing quality and efficiency, this study aimed to design a small ultrasonic vibration assisted EDM machine, which can effectively avoid spark concentration and abnormal arc generation.
  Keywords: EDM; electromagnetic induction; non-contact; ultrasonic vibration; EDM machine.
  
  
• Spectrophotometric determination of buspirone HCl and doxazosin mesylate using citrate-capped silver nanoparticles.  
  by Magda Ayad, Hisham Ezzat, Mervat Hosny, Naglaa Kabil 
  Abstract: A simple and rapid spectrophotometric method was developed for determination of buspirone HCl and doxazosin mesylate in bulk and pharmaceutical formulations. In this article silver nanoparticles (Ag-NPs) were prepared chemically using sodium citrate as reducing and stabilizing agent. Silver nanoparticles showed an absorption band at 420 nm. Aggregation of citrate stabilized silver nanoparticles (Ag NPs) were used for quantitative determination of the studied drugs with formation of a new red shifted band at 545, 690 nm for buspirone HCl and doxazosin mesylate respectively. Different experimental factors were optimized and the calibration curves were linear with concentrations of (0.10-0.60 ?g/mL), (5.0-14.0 ?g/mL) for buspirone HCl and doxazosin mesylate respectively. Validation of the analytical performance of the method was carefully investigated, and the results were satisfactory.
  Keywords: silver nanoparticles; buspirone HCl and doxazosin mesylate.
  
  
• Carbon microsphere anchored g-C3N4 for enhanced photocatalytic properties
  by Qingbo Yu, Kuan Yang, Huiqin Li 
  Abstract: Graphitic carbon nitride (g-C3N4) is a new type of semiconductor material with highly physicochemical stability. In this paper, carbon microsphere anchored g-C3N4 composites were prepared by blending g-C3N4 with polyvinyl alcohol at high temperature. The structure and morphology of the composites were characterized by X-ray diffraction, infrared spectroscopy, ultraviolet spectroscopy, scanning electron microscopy, and so on. Their properties were tested by electrochemical and photocatalytic experiments. The results show that carbon microspheres can be loaded on the surface of g-C3N4 without changing the basic structure of g-C3N4 with a proper ration between polyvinyl alcohol and g-C3N4. Compared with the pure g-C3N4, the photocurrent after modification is increased by 1000 times and the photocatalytic degradation rate is increased by 2.8 times.
  Keywords: Carbon nitride; Polyvinyl alcohol; Carbon microsphere; Photocatalytic
  
  
• Construction C/g-C3N4 with synergistic performance toward high photocatalytic performance
  by Qingbo Yu, Huiqin Li, Kuan Yang, Qixiang Xu, Xianhua Li 
  Abstract: Aromatic carbon (C) doped graphitic carbon nitride (g-C3N4) is one of the effective strategies to improve the photocatalytic performance of g-C3N4. The present work developed a feasible method to construct C/g-C3N4 through carbonizing the mixture of g-C3N4 and phenol-formaldehude (PF) obtained in suit polymerization. This synthesis method not only improves the interaction of PF and g-C3N4, but also promotes aromatic carbon doped g-C3N4 in the subsequent calcinations process. The resulted C/g-C3N4-600 catalysts show developing optoelectronic properties, superior photocatalytic activity and higher surface area (1336 cm2 g-1), owning to improve the π-conjugation system and distinctive morphology.
  Keywords: C/g-C3N4; Optoelectronic properties; Surface area; Photocatalytic properties
  
  
• Influence of rake angle and nose radius on optical silicon nanomachining feed rate and surface quality – A modelling, prediction and Optimization study
  by Lukman N. Abdulkadir 
  Abstract: Silicon is widely used in infrared (IR) optics due to its high transmissive ability at wavelength (?) ranging from 1.2 - 6.0 µm. However, optical components of high quality require surface roughness (Ra) below or equal to 8 nm. Ultra-high precision single-point diamond turning of optical silicon has filled this gap due to enhanced chip removal, well-defined grain structure and low coefficient of friction of diamond tool. To attain both high form accuracy and optical surface integrity, appropriate choice of cutting conditions and tool geometry that would facilitate predictive accuracy needs be made. This study aimed at reducing optical silicon Ra value by varying feed rate, nose radius and rake angle while keeping cutting speed, clearance angle and depth of cut constant. Using Box Behnken (BBD) design of experiment, regression analysis and analysis of variance were used to find parameter influence on the response variable for accurate model formulation. The model was afterward optimized by setting desired goal for each factor and response using composite desirability function approach. It was observed that the recommended Ra value of less than 8 nm was achieved with standard runs 5, 6, 8, 9, and 10 with their Ra values ranging from 1.8 - 7 nm. Furthermore, at high tool negative rake angle and nose radius, surface roughness increase due to high feed rate was noted to be greatly reduced. Additionally, with increase in tool nose radius at 0° rake angle, poor surface quality known to result from high feed rate also reduced.
  Keywords: Optical silicon; surface roughness; subsurface damage; response surface methodology; Box Behnken design; desirability function