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"In this paper, two highly sensitive photonic crystal fiber (PCF) structures with microstructure core and cladding have been demonstrated for Ethanol sensing. The microstructure core of both proposed PCFs is designed with supplementary holes in an octagonal formation. We have investigated the relative sensitivity and the confinement loss of the proposed PCF structures employing a full vectorial finite element method (FEM). The proposed PCFs work at a wide transmission band covering 0.8 µm to 2 µm and exhibit high sensitivity and low confinement loss simultaneously. The numerical analysis shows that the circular shape of air holes in the first ring is a more salient attribute for increasing sensitivity and the presence of the square shape of air holes in the first ring shows better performance to reduce confinement loss."

"In this paper, two highlysensitive photonic crystal fiber (PCF) structures with microstructure core and claddinghave been demonstrated for Ethanol sensing. Themicrostructure core of both proposedPCFs is designed with supplementary holes in an octagonal formation. We have investigated therelative sensitivity and the confinement loss of the proposed PCF structuresemploying a fullvectorial finite element method (FEM). The proposed PCFs work at a widetransmission band covering 0.8 µm to 2 µm and exhibit high sensitivity and lowconfinement loss simultaneously. The numerical analysis shows that the circular shape of air holes in the first ring is a moresalient attribute forincreasing sensitivity and the presence of the square shape of air holes in the first ring showsbetter performance to reduce confinement loss."

"ABSTRAKFiber kristal fotonik adalah satu jenis Fiber baru yang tersusun dari susunan periodik hole-udara pada struktur silika. Fiber jenis ini mempunyai sifat-sifat optik yang tidak dimiliki oleh fiber konvensional seperti sifat propagasi endlessly single mode, rendah attenuasi, dan diameter mode medannya lebih kecil dari diameter intinya. Sifat-sifat optik fiber jenis ini telah dipelajari pada simulasi dengan bantuan software COMSOL. Berdasarkan hasil simulasi, untuk panjang gelombang 1,064 μm, fiber kristal fotonik LMA-20 memiliki numerical aperture sebesar 0,0572, diameter modal medan sebesar 16,2 μm, dan birefringence nol. Untuk memvalidasi sifat-sifat optiknya, khususnya perubahan polarisasi pada fiber kristal fotonik LMA-20 dan ESM-12-01, dilakukan analisis menggunakan vektor dan matrik Jones. Hasil eksperimen memperkuat dan selaras dengan hasil yang didapat dalam simulasi bahwa birefringence pada fiber LMA-20 dan ESM-12-01 adalah nol jika tidak ada pertubasi pada fiber tersebut.

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ABSTRACTThe photonic crystal fiber is a new class of fiber that consists of periodic arrangement of air-holes in a structure of silica. This fiber has optical properties that does not exist in the conventional optical fiber such as the propagation endlessly single mode singlemode, low attenuation, and a mode field diameter smaller than its core. The properties of this fiber are studied in simulation by using software COMSOL. According to the simulation, for a wavelength of 1.064 μm, the PCFLMA-20 has a numerical aperture equal to 0.0572, the diameter of the mode field is 16.2 μm and birefringence is zero. In addition, it is not singlemode even at wavelength of 1.55 μm. Otherwise, the PCF ESM-12-01 is singlemode for wavelength greater than 0.45 μm. To validate the optical properties, in particular the evolution of the state of polarization in the PCF LMA-20 and ESM-12-01, used the Jones vector and matrices to analyze the experimental results. The experimental results confirm those obtained in the simulation that: birefringence LMA-20 and ESM-12-01 is zero if there is no disturbance of the fiber."

"The present work aims to improve the microstructure and hardness related properties of age hardened Al6061-SiC reinforced composites produced by a two stage stir casting method. Three composites with 2, 4, and 6wt. % (35-40?m) of SiC reinforcement are subjected to microstructural examination and hardness test at different locations to analyse the uniform distribution of the reinforcements in the matrix. As-cast composites are solution-treated at 558°C, followed by an aging treatment conducted at 100, 150, and 200°C, during which peak hardness values are noted. The peak aged samples are subjected to hardness and wear tests. In line with the objectives, ranges from 80-100% and 120-145% additional increase in hardness values are observed over as-cast alloy during the aging treatment conducted at 100, 150 and 200°C, respectively. Lower temperature aging shows substantial improvement in hardness and wear resistance over high temperature aging in each respective group. Also higher weight percentages of reinforced composites show excellent wear resistance, due to the presence of eroded iron particles from the counter surface which is regarded as a beneficial effect during the wear test. The presence of SiC particles provides more sites for the nucleation of fine precipitates. These fine precipitates hinder the movement of dislocation and thus increases hardness as well as wear resistance after the precipitation hardening treatment."

"The present study investigated the mechanical properties and microstructure of ultrafine grained (UFG) brass processed by four passes of equal channel angular pressing (ECAP) and annealed at elevated temperatures. The mechanical properties of all samples were assessed using tensile and micro-hardness tests. Microstructure analysis was performed using optical microscopy (OM) and scanning electron microscopy (SEM). Ultimate tensile strengths (UTS) and yield strengths (YS) of 878 and 804 MPa, respectively, ductility of 15%, and hardness of 248 HV were obtained for samples processed by four passes of ECAP with equivalent true strain of 4.20. Annealing at 300°C caused UTS and YS to decrease significantly, to 510 and 408 MPa, respectively, ductility to increase to 28%, and hardness to decrease to 165 HV. Fractography analysis of un-annealed samples after four ECAP passes showed small brittle fractures with shallow dimpling. Ductile failures were found on annealed samples. After four ECAP passes, the microstructure of un-annealed samples was UFG and dominated by lamellar grain with shear band. In contrast, after annealing, the microstructure changed due to recrystallization, showing nucleation and grain growth."

"The aim of this handbook is to provide a comprehensive summary of sensing and measurement in precision manufacturing, which is essential for process and quality control. The importance of precision sensing and measurements lies not only in the ability to distinguish whether the manufactured part meets the assigned tolerances through inspection but also, in many cases, reduce the deviation of the manufactured part from the designed values through improvement of the process or compensation manufacturing based on the sensing and measurement results. The information provided in the book will be of interest to industrial practitioners and researchers in the field of precision manufacturing sensing and measurements."

"This book about preparation of liquid crystalline elastomers, applications of liquid crystalline elastomers, liquid crystal elastomers and light, electro-opto-mechanical effects in swollen nematic elastomers, the isotropic-to-nematic conversion in liquid crystalline elastomers, and order and disorder in liquid-cystalline elastomers."

"Latar Belakang: Polymer Induced Liquid Precursor (PILP) merupakan remineralisasi biomimetik dengan menggunakan bahan polimer anionik sintetik yang dapat menggantikan peran protein non kolagen dalam remineralisasi intrafibrillar. Asam poliaspartik merupakan salah satu material analog protein non kolagen yang penting dalam proses PILP. Nanodroplet yang terbentuk dalam proses PILP mampu berdifusi ke dalam intrafibrillar kolagen ataupun gap zone yang memiliki ukuran 40 nanometer dan mengalami kristalisasi. Tujuan: Menganalisis remineralisasi intrafibrillar dan ukuran kristal hidroksiapatit yang terbentuk. Metode: Evaluasi efek asam poliaspartik dalam proses PILP pada remineralisasi intrafibrillar selama 3, 7 dan 14 hari melalui TEM dan ukuran kristal hidroksiapatit yang terbentuk melalui XRD. Hasil: Ada perbedaan signifikan secara evaluasi deskriptif antar kelompok remineralisasi 3, 7 dan 14 hari terhadap kelompok demineralized dentin pada remineraliasi intrafibrillar. Tidak terdapat perbedaan bermakna antar kelompok remineralisasi maupun kelompok demineralized dentin terhadap ukuran kristal hidroksiapatit. Kesimpulan: Asam poliaspartik dalam proses PILP memiliki potensi dalam remineralisasi intrafibrillar.

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Background: Polymer Induced Liquid Precursor (PILP) is a biomimetic remineralization using synthetic anionic polymer material that can replace the role of non-collagen proteins in intrafibrillar remineralization. Polyaspartic acid is one of the non collagen protein analog materials that is important in the PILP process. Nanodroplet formed in the PILP process is able to diffuse into intrafibrillar collagen or gap zones that have a size of 40 nanometers and crystallize. Purpose: To analyze the intrafibrillar remineralization and the size of hydroxyapatite crystal formed.

Methods: Evaluation of the effect of polyaspartic acid in PILP process on intrafibrillar remineralization for 3, 7 and 14 days through TEM and the size of hydroxyapatite crystal formed through XRD.

Result: There was a significant difference in descriptive evaluation between remineralization groups of 3, 7 and 14 days against the demineralized dentin group in intrafibrillar remineralization. There were no significant differences between the remineralization group and the demineralized dentin group to the size of hydroxyapatite crystals.

Conclusion: Polyaspartic acid within PILP process has potential ability in intrafibrillar remineralization."