Machining and Characterization of Multidirectional Hybrid Silica Glass Fiber Reinforced Composite Laminates Using Abrasive Jet Machining

Silicon - Machining of multidirectional Hybrid Fiber Reinforced Composite (HFRC) is a challenging task because of defects like matrix cracking, fiber pullouts, delamination, burr formation, and...     

Experimental Investigation for Generation of Micro-Holes on Silicon Wafer Using Electrochemical Discharge Machining Process

Silicon - Electrochemical discharge machining (ECDM) is a versatile machining process due to its applicability to machine different materials regardless to their properties. In this work, machining...     

A Novel Approach on Reusing Silicon Wafer Kerf Particle as Potential Filler Material in Polymer Composite

Silicon - In solar panel production stage, it is unavoidable to neglect the huge amount of solar grade silicon particles displaced during the slicing of silicon ingot operation. A subject of the...     

Effect of Microstructure on Material-Removal Mechanisms and Damage Tolerance in Abrasive Machining of Silicon Carbide

Effects of microstructural heterogeneity on material-removal mechanisms and damage-formation processes in the abrasive machining of silicon carbide are investigated. It is shown that the process of material removal in a conventional silicon carbide material with equiaxed-grain micro-structure and strong grain boundaries consists of the formation and propagation of transgranular cracks which results in macroscopic chipping. However, in a silicon carbide material, containing 20 vol% yttrium aluminum garnet (YAG) second phase, with elongated-grain micro-structure and weak grain boundaries, intergranular micro-cracks are formed at the interphase boundaries, leading to dislodgment of individual grains. These different mechanisms of material-removal affect the nature of machining-induced damage. While in the conventional silicon carbide material the machining damage consists of transgranular median/radial cracks, in the heterogeneous silicon carbide material, abrasive machining produces interfacial micro-cracks distributed within a thin surface layer. These two distinct types of machining damage result in a different strength response in the two forms of silicon carbide materials. In the case of the conventional silicon carbide, grinding damage results in a dramatic decrease in strength relative to the as-polished specimens. In contrast, the ground heterogeneous silicon carbide specimens show no strength loss at all.     

Grape Seed Oil Characterization: A Novel Approach for Oil Quality Assessment

The amount of organic pomace, left behind agricultural processes, is continuously rising in accordance with industrial progress. Grape pomace, generated in the wine industry all over the world, represents a raw material for obtaining valuable products. Grape seeds are especially rich in oil containing bioactive compounds that can have various health‐related effects. The aim of the study is to compare the quality of seed oils obtained from six white grapes, including two Serbian autochthonous varieties. Linoleic acid, associated with numerous health benefits, is the major fatty acid in all samples (≈66% of total); α‐tocopherol is the main tocopherol homologue. Total polyphenol content ranges from 73.4 to 104.3 mg of gallic acid equivalents per 100 g. In order to provide comprehensive information about antioxidant capacity of grape seed oil (GSO), three tests are performed (ferric ion reducing antioxidant power; 2,2’‐diphenyl‐1‐picrylhydrazyl, and 2,2’‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulphonic acid) radical scavenging). Antimicrobial activity is investigated against different strains; however, GSO inhibits the growth of Staphylococcus aureus and Candida albicans. Obtained results are used to develop a novel approach for oil quality assessment. Calculated oil quality scores (OQS) reveal no significant difference between international and autochthonous varieties, although Smederevka stands out as the most potent one. Practical applications : Considering the progressive waste increase in the wine industry and keeping in mind all health‐promoting effects of grape seed oil (GSO), it is clearly observed that oil production represents a profitable and sustainable utilization of grape seeds. The results of the present study show that GSO is a rich source of compounds with antioxidant and antimicrobial properties. In addition, this work provides deeper insight into a quality of Serbian autochthonous grape varieties that are still insufficiently explored. Furthermore, the proposed oil quality score could be used as a comprehensive and unbiased method that enables quality assessment of oils. This tool can find practical application in comparing different plant oils regarding their compositional and functional properties. Finally, it would contribute to making some general oil intake recommendations.     

Abrasive Water Jet Machining of Al6063/B4C/ZrSiO4 Hybrid Composites: a Study of Machinability and Surface Characterization Analysis

Silicon - This paper reports the machinability studies on aluminium hybrid composites of different compositions by using abrasive water jet machining process. In this study, aluminum hybrid metal...     

Machinability of Silicon and German Silver in Micro Electrical Discharge Machining: a Comparative Study

Silicon - This paper introduces an experimental investigation of micro hole drilling on two different categories of material such as silicon and german silver using micro electrical discharge...     

Optimization of SiC Abrasive Parameters on Machining of Ti-6Al-4V Alloy in AJM Using Taguchi-Grey Relational Method

Silicon - In this research, multi response Taguchi-grey relational approach was employed to optimize the machining parameters of Ti-6Al-4V alloy in abrasive water jet process. The main aim of this...     

Investigation on Slicing Behavior of Single Crystal Silicon Wafer in AWJM and Influence of Micro Dimple Textured Surface for Solar Applications

Silicon - The current investigation focuses on the slicing characteristics of silicon, a hard and brittle solid that is very difficult to cut, with abrasive water jet machining (AWJM) process by...     

Silicon Carbide: A Novel Catalyst Support for Heterogeneous Catalysis

Progress in developing a new class of support materials based on silicon carbide (SiC)is reviewed. Silicon carbide has superior mechanical and thermal properties which, coupled to chemical inertness,avoids several of the problems inherent in the use of commercial oxide and carbon based supports and catalysts. High surface area SiC can now be prepared easily in a commercially viable shape,with good mechanical properties,and at reasonable cost.I t can be shaped directly into monolith or honeycomb forms including some catalytically active material, rendering fabrication simple and cost effective. Furthermore, it can be modified for specific catalytic applications through the addition of metals. In many respects, it combines the best properties of oxide and carbon based supports without suffering many of their disadvantages.     

Novel Fast-Curing Electrically Conductive Adhesives from a Functional Epoxy and Micro Silver Flakes: Preparation,Characterization, and Humid-Thermal Aging

In this study, novel fast-curing electrically conductive adhesives were prepared from a functional epoxy, a reactive diluent, a silane coupling agent, a curing agent, and micro silver flakes. Differential scanning calorimetry, Fourier transform infrared spectroscopy, four-probe method, shear test, impact test, scanning electron microscopy, and energy dispersive spectroscopy revealed the physical, electrical, mechanical, and thermal properties of these electrically conductive adhesives. They were cured at 120°C and 150°C for 15 min, and had low bulk resistivity, high shear strength, and low water absorption. They can be used in the electronic packaging and improve the related production efficiency greatly.     

基于B样条的五轴联动加工刀轴运动的优化

依据建立的刀轴表面双重B样条曲线,用格式相同的B样条将刀轴运动路径和刀尖曲线参数化,根据运动方向派生出的最大角速度、角加速度调整刀轴的运动,从而提出了一种调整刀轴运动的优化方法,使五轴联动加工在整个高速加工过程中刀轴运动地更加合理、准确。     

A Novel Approach for Minimization of Tool Vibration and Surface Roughness in Orthogonal Turn Milling of Silicon Bronze Alloy

Silicon - The advanced manufacturing system is aimed to produce components at right quantity, quality and cost. Turnmilling is one of the advanced machining techniques that combines turning and...     

A Novel Polymeric Precursor for Boron Nitride Ceramics: Synthesis,Characterization, and Ceramic Conversion

A new polymeric boron nitride (BN) precursor poly[(phenylamino)borazine] (PPAB) with good melt‐processing performance was successfully synthesized by reaction of B‐trichloroborazine (TCB), aniline, and N‐methylaniline under mild conditions. The as‐synthesized PPAB as well as its structural evolution during the ceramic conversion was studied by means of various complementary techniques. The effect of process parameters including monomer ratio, reaction time, and reaction temperature on the properties of polymers was investigated, and the optimized parameters were obtained. Gel permeation chromatography (GPC) analysis of typical PPAB revealed that the number‐average molecular weight (M_n) was 30,520 Da and the polymerization degree was 319. The polymer could be converted to BN ceramics under ammonia atmosphere at 1200°C with carbon content as low as 0.9wt%. The PPAB polymer could be melt‐spun into continuous polymer fibers by hand drawing, which could be further transformed into BN ceramic fibers with good quality. The PPAB polymer is promising for applications that require BN precursor with stable melt processability.     

Characterization and Investigation of Mechanical Properties of Aluminium Hybrid Nano-composites: Novel Approach of Utilizing Silicon Carbide and Waste Particles to Reduce Cost of Material

Silicon - In the past few decades, lightweight materials were become a global concern due to effective and sustainable are evidence most popular utilizing in industrial sectors. This research would...     

A Novel Approach to Investigate Analog and Digital Circuit Applications of Silicon Junctionless-Double-Gate (JL-DG) MOSFETs

Silicon - The double gate junctionless transistor (DG-JLT) has become the most promising device in sub nano-meter regime. DGJLT based circuits have improved performance and simpler fabrication than...     

Characterization and Discrimination of Ancient Grains: A Metabolomics Approach

Hulled, or ancient, wheats were the earliest domesticated wheats by mankind and the ancestors of current wheats. Their cultivation drastically decreased during the 1960s; however, the increasing demand for a healthy and equilibrated diet led to rediscovering these grains. Our aim was to use a non-targeted metabolomic approach to discriminate and characterize similarities and differences between ancient Triticum varieties. For this purpose, 77 hulled wheat samples from three different varieties were collected: Garfagnana T. turgidum var. dicoccum L. (emmer), ID331 T. monococcum L. (einkorn) and Rouquin T. spelta L. (spelt). The ultra high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-QTOF) metabolomics approach highlighted a pronounced sample clustering according to the wheat variety, with an excellent predictability (Q²), for all the models built. Fifteen metabolites were tentatively identified based on accurate masses, isotopic pattern, and product ion spectra. Among these, alkylresorcinols (ARs) were found to be significantly higher in spelt and emmer, showing different homologue composition. Furthermore, phosphatidylcholines (PC) and lysophosphatidylcholines (lysoPC) levels were higher in einkorn variety. The results obtained in this study confirmed the importance of ARs as markers to distinguish between Triticum species and revealed their values as cultivar markers, being not affected by the environmental influences.     

Synthesis,Structure Investigation,DFT Analysis And Dielectric Characterization of Substituted Pyridinylidenepropanedinitrile (CMHQCPP) Nanostructure: Novel Approach

Journal of Inorganic and Organometallic Polymers and Materials - For the first time, a novel...     

Synthesis,Characterization and Adsorption of Bisphenol A Using Novel Hybrid Materiel Produced from PANI Matrix Reinforced by Kieselguhr

Journal of Inorganic and Organometallic Polymers and Materials - This study investigated the preparation of new adsorbent based PANI and Kieselguhr (KG). The produced materials were characterized...     

硅晶片抛光用高纯度大粒径硅溶胶的研究

本文采用硅粉水解-胶粒整理法制备硅晶片抛光所用硅溶胶,考察了单质硅粉的加入量、反应时间、反应温度、硅溶胶底液浓度、催化剂种类及用量对硅溶胶胶粒平均粒径增长的影响,得到最佳工艺条件:单质硅粉的最佳加入量为25 g、反应时间7h、反应温度80℃、硅溶胶底液的质量浓度为8％、选稀氨水为催化剂、用量为12 mL,在此条件下可制备得到平均粒径为20 nm的硅溶胶产品.经过多次粒子生长可以制备得到适用于硅晶片抛光产业的高纯度大粒径硅溶胶.