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The paper presents results on femtosecond laser irradiation-induced modification of the optical properties of a composite material – gold nanoparticles embedded into a borosilicate glass host. The process is initiated by laser pulses delivered by a Ti:sapphire laser system with pulse duration of 35 fs. The glass samples are prepared by melt quenching with gold added as hydrogen tetrachloroaurate (III) hydrate to the initial composition. Post-fabrication annealing leads to a homogeneous formation of nanoparticles in the glass; varying the annealing parameters results in producing nanoparticles with different sizes and shapes. The laser irradiation of the samples induces significant modification of the optical spectra of the glass through changes of the nanoparticles characteristics. The effects are studied of the laser fluence, laser wavelength and laser pulses number. The heat diffusion equation is applied to estimate the temperature evolution and explain the modifications observed. The results demonstrate this technique’s efficiency in modifying the nanoparticles properties with a high 3D spatial resolution, which can be useful in fabrication of integrated optical systems.

The inspection of radiation shielding specimens in the composition xBaO : (40-x)SiO2 : 25ZnO : 30B2O3 : 5Al2O3, where x = 10, 15, 20, 25, 30, 35, and 40 mol % of borosilicate glasses went on to radiation shielding parameters, found that the MAC, the Zeff, the atomic cross-section, and the electronic cross-section have the same trends when added BaO increase, but when the energy increases, all values of the four parameters decreased with increasing of the energy ranges. The result of Ne was described as the atomic radius of BaO that affects the probability of interactions in the Compton scattering ranges. The results of HVL and MFP demonstrated that the lower both parameters affected volume requirement and decreased the average distance when photon traveled in the material, which can design the physical characteristic of the radiation shielding specimens.

Hydroxyapatite Ca10 (PO4) 6 (OH) 2 is a calcium compound whose chemical composition is similar to human bone minerals. In this study, hydroxyapatite was formed into a composite material by adding borosilicate (borax and silica). For the formation of this composite material, the Hydroxyapatite borosilicate composition has been adjusted, namely: 90:10, 85:15, 80:20, 75:25, 70:30 wt.%. The samples were made with different compacting forces, namely 5 KN, 15 KN, and 25 KN with a sintering temperature of 800 ° C. 0.003734 gr / mm3. While the lowest density value is found in the composition 75:25 Wt.%, The compacting force is 5 KN with a value of 0.002436 gr / mm3. The decrease in the density value is influenced by the composition and compaction force applied. The greater the borosilicate composition, the lower the density. Meanwhile, the greater the compacting force applied, the density will increase.

© 2020 IOP Publishing Ltd. In this work, it is shown that controllable increases in chemical reactivity of borosilicate glass can be induced through spatially resolved femtosecond laser irradiation at fluence values significantly lower than the damage threshold. The hydrofluoric acid etch rate has been found to be closely correlated to the reduction in optical transmission of the glass at 488 nm, which is, in turn, governed by the production of boron-oxygen hole centers. The combination of laser irradiation below the ablation threshold followed by chemical etching is shown to yield surfaces that have a roughness lower than those achieved by either laser or chemical etching alone. Application of this effect to the manufacture of freeform Laplacian optics is demonstrated.

Mixed alkali borosilicate glasses doped with 2% vanadium oxide were synthesized by conventional melt-quench method. The Micro structure of the materials was analysed using XRD, SEM and EDX spectrum. Optical nature of glasses was studied by computing optical bandgaps with absorption spectral data. Covalent nature of glasses was estimated correlating optical bandgap energy with EPR spectral data. The metallization criterion of glasses was evaluated from the physical parameters. FTIR and Raman spectral techniques were used to identify the structural groups of the borates and silicates that are formed with addition of modifiers. Emission spectra were recorded at excitation wavelength of 350 nm and their thermal nature was also studied using TGA/DTA techniques.

Uniform and well-adherent SnO2 thin films, with thickness ranging from 60 nm to 6 μm, were deposited on borosilicate glass substrate by Successive Ionic Layer Adsorption and Reaction (SILAR) technique. A micro-controlled SILAR unit was employed to precisely monitor the deposition conditions. The effect of precursor concentration and post-deposition annealing on the micro-structural and optical properties of SnO2 thin films were studied in detail. The films were found to possess tetragonal rutile structure. The crystallite size of the films increased with solution molarity. Microstructural properties were analyzed using Scherrer, Modified Scherrer, Williamsons-Hall and Size-Strain plot techniques. Different optical properties such as band gap, skin depth, extinction coefficient, Urbach energy etc were determined. The post-deposition annealing at a moderate temperature of 573 K was found to enhance the crystallite size of the films while the density of the defect energy states reduced.

Different compositions (x) of lead-bismuth titanate borosilicate (PBTB) glasses have been synthesized using a conventional melt-quenching method in the compound 55[(PbxBi1−x)TiO3]−44[2SiO2.B2O3], (x = 0.0, 0.3, 0.5, 0.7 and 1.0) mixed with 1 mol % of graphene nanoplatelets (GNPs). XRD analysis exhibited the synthesis of clear PBTB glasses which confirmed the amorphous nature. Synthesized glasses have been converted into glass-ceramics (GCs) using a differential thermal analysis (DTA) results to understand the crystallization mechanism. XRD results described the crystalline behavior of GC samples and distinct phase formation. The surface morphology of the GCs was analyzed using a scanning electron microscope (SEM). Energy dispersive X-ray analysis (EDAX) have been also performed to verify the elemental composition of the GC sample, PBTG0.5735 F (x = 0.5). The variation in relative dielectric constant (ε r) and dissipation factor (D) by increasing temperatures was obtained at different frequencies. The GC sample PTG1.0746 F (x = 1.0) showed a maximum value of dielectric constant among all glass ceramic samples.

This paper reports surface nanostructuring of borosilicate glass covered with a water layer and the production of ~150 nm diameter pits using SiO2/Au core/shell microparticles under excitation with 50 fs pulses (? = 780 nm) using the optical scheme of an inverted microscope with a 100?, NA = 1.4 objective. We compare the thresholds for hole formation in glass with the use of SiO2/Au and uncoated SiO2 microparticles. The threshold is 0.7 J cm-2 for SiO2/Au and 2.9 J cm-2 for SiO2 microparticles, which coincides with the threshold for nanostructuring by a focused femtosecond pulse without microparticles: 3 J cm-2. Femtosecond pump ? probe spectroscopy has been used to study the relaxation dynamics of laser pulse energy absorbed in a Au nanoparticle and the dynamics of energy dissipation to the ambient medium. The threshold for cavitation bubble formation in water with SiO2/Au has been determined to be 0.06 mJ cm-2, which is a factor of 30 lower than the bubble formation threshold in the case of uncoated SiO2 microparticles.

Glass has unique properties for micro fluidic, MEMS and optical applications. However, poor machinability of glass materials limit its applications. ECDM process is one of the most utilized micro machining process for fabrication of glass micro products. In ECDM thermal energy of discharges utilizes to provide thermal loading for removal of material. However, controlled thermal loading requires for machining of glass materials owing to its poor thermal conductivity. High thermal stresses may develop at high thermal loading, which leads to uncontrolled facture of glass material. Therefore, a thorough discussion is needed to understand the effect of thermal loading on glass materials. In this study, the experiments are conducted to investigate the thermal loading effect on borosilicate glass during ECDM process. Also, an analytical model is developed to estimate the induced thermal stress during ECDM process. Theses thermal stresses are discussed during drilling of micro hole on work material. After discussion three zones are identified for machining of borosilicate glass using ECDM process, wherein zone-II (i.e. from 44 V to 52 V applied voltage) is identified for safe machining.

The color conversion glass ceramics which were made of borosilicate matrix co-doped (SrBaSm)Si2O2N2: (Eu3+Ce3+) blue–green phosphors were prepared by two-step method in co-sintering. The change in luminescence properties and the drift of chromaticity coordinates (CIE) of the (SrBaSm)Si2O2N2: (Eu3+Ce3+) blue–green phosphors and the color conversion glass ceramics were studied in the sintering temperature range from 600 °C to 800 °C. The luminous intensity and internal quantum yield (QY) of the blue–green phosphors and glass ceramics decreased with the sintering temperature increasing. When the sintering temperature increased beyond 750 °C, the phosphors and the color conversion glass ceramics almost had no peak in photoluminescence (PL) and excitation (PLE) spectra. The results showed that the blue–green phosphors had poor thermal stability at higher temperature. The lattice structure of the phosphors was destroyed by the glass matrix and the Ce3+ in the phosphors was oxidized to Ce4+, which further caused a decrease in luminescent properties of the color conversion glass ceramics.

The detection of neutrons above background levels is an indication of nuclear materials, creating significant applications for handheld neutron detectors in homeland security. For such applications, a 10B and 6Li enriched, scintillating glass neutron detector was designed. The model is compact enough to be used as a handheld detector and is equipped with machine learning capabilities to determine the location of the source and discriminate a neutron from a gamma. Lithium Borosilicate glass samples, with up to 70% 10B and 6Li content, and doped with Tb and Eu, were engineered to optimize the performance of the detector. The scintillation properties and neutron/gamma detection capabilities of the glass samples were tested. The model detector's performance was simulated in Geant4 and the simulation data was utilized for machine learning to predict the location of the source with an Artificial Neural Network (ANN). The reported handheld neutron detector design with the implemented artificial intelligence capability can achieve 99.9% accuracy in neutron/gamma discrimination, 8.9% error in radial angle estimates, and 2.9% error in azimuthal angle estimates.

We demonstrate the simultaneous polymerization of 3,4-ethylenedioxythiophene (EDOT) monomer stock solution ink and printing of the resulting poly(3,4-ethylenedioxythiophene) (PEDOT) via plasma-assisted inkjet printing. The plasma-induced polymerization of EDOT is confirmed via Raman and Fourier-transform infrared (FT-IR) spectroscopies of the printed line. Furthermore, we also achieve plasma-induced polymerization of PEDOT with poly(styrenesulfonate) (PSS) for the synthesis of an electrically conductive film from EDOT. Consequently, we fabricate a PEDOT/PSS film with conductivity of the order of 10−2 Scm−1 on a borosilicate glass substrate. Our approach achieves (i) direct patterning with PEDOT polymerization and (ii) doping with PEDOT polymerization as separate processes, and our results suggest that on-site printing of conductive PEDOT/PSS with polymerization is possible through the use of an inkjet system with resistance to even the strong acidity of PSS.

In this contribution we present the first results devoted to studies of structure, morphology and magnetic properties of magnetic alkali-borosilicate glasses prepared by induction melting. This procedure permits to fabricate a large amount of two-phase glasses with magnetic properties due to self-assembled magnetite (Fe3O4) nanoparticles and with branched dendrite-like structure of channels formed by a chemical unstable phase. After withdrawal of this phase we have obtained the porous matrices with two different average pore diameters: ~6 nm and ~60 nm. The empty pore spaces in these matrices were filled by ferroelectrics KH2PO4 from water solution. It is shown that application of external magnetic fields above B=1 T results in a linear growth of the ferroelectric phase transition temperature TC on 6 K at B=10 T due to magnetostrictive properties of porous matrices.

Er3+/Yb3+ codoped BaGdF5 glass ceramics have been prepared and used to develop a portable all-fiber temperature sensor based on fluorescence intensity ratio technique. XRD and TEM results affirm the generation of BaGdF5 nanocrystals in the borosilicate glass. Eu3+ ions are used as spectral probe to investigate external environment around rare earth (RE) ions. Intense green upconversion emissions from Er3+ ions are detected in the BaGdF5 glass ceramics and their intensity are enhanced about three orders of magnitude after heat treatment, which is attributed to the enrichment of RE ions in the BaGdF5 phase. Based on green upconversion emission from Er3+ ions, the temperature sensing property of the portable all-fiber temperature sensor is studied. The maximum absolute sensitivity is 15.5 × 10−4 K−1 at 567 K and the relative sensitivity is 1.28% K−1 at 298 K, respectively.

In this paper we report on ultra flat supercontinuum generation in dual core photonic crystal fiber pumped in the normal dispersion regime. The fiber cladding is fabricated from custom NC21 borosilicate glass while the fiber cores is made of commercially available F2 high index lead-silicate glass from Schott Corp. We investigated the supercontinuum characteristics for single and double core excitation by a Ti:Sapphire oscillator delivering 100 fs pulses centered at 800 nm with an energy of 4.2 nJ. Dual core pumping resulted in appreciable flattening of the supercontinuum spectra in the range 875 – 950 nm.

The hot embossing of glass with a size on the submicron or micron level is a target of interest for the industrial production of products such as microdevices. For fluidic micro chip applications, polymer materials have been used with the advantage of a relatively low cost of fabrication. However, glass is suitable for high-temperature applications such as in microreactors. Although glass is also a good candidate material for optical devices because of its enhanced optical properties, the development of mold materials has not been established for the hot embossing of glass. In this study, we used Ni–W as a mold material for the hot embossing of glass. A plated Ni–W film has a high heat resistance and a linear expansion coefficient, properties that are similar to those of glass materials. Focused ion beam (FIB) machining was employed for the micron and submicron structurings of a Ni–W mold material. Borosilicate glass, D263, was used as glass material. Glass patterns of 0.4 µm width were obtained by hot embossing with the Ni–W mold.

During high repetition rate (>200 kHz) ultrafast laser waveguide writing, visible heat modified zones surrounding the formed waveguide occur as a result of heat accumulation. The radii of the heat-modified zones increase with the laser net fluence, and were found to correlate with the formation of low-loss and cylindrically symmetric optical waveguides. A numerical thermal model based on the finite difference method is applied here to account for cumulative heating and diffusion effects. The model successfully shows that heat propagation and accumulation accurately predict the radius of the 'heat modified' zones observed in borosilicate glass waveguides formed across a wide range of laser exposure conditions. Such modelling promises better control of thermal effects for optimizing the fabrication and performance of three-dimensional optical devices in transparent materials.

Laser swelling of borosilicate and soda-lime glass is shown for wavelengths of 193 and 248 nm. Very smooth patterns up to 45 nm high were generated by KrF laser (248 nm) irradiation of borosilicate glass at a fluence of 1.5 J/cm2. At 193 nm laser wavelength, lower heights (up to 13 nm) and lower swelling threshold fluences (0.1 J/cm2) were observed due to higher material absorption. For the less absorbing soda-lime glass higher fluences than for the borosilicate glass are needed to establish elevated structures. Gratings in borosilicate glass with sub-micron periodicity demonstrate the high resolution of the method. The results can be explained by a thermo-physical model based on the change of the glass transition temperature due to fast cooling after the pulsed laser irradiation.

We study the formation mechanism of rims created around femtosecond laser ablated craters on glass. Experimental studies of the surface morphology reveal that a thin rim is formed around the smooth craters and is raised above the undamaged surface by about 50–100 nm. To investigate the mechanism of rim formation following a single ultrafast laser pulse, we perform a one-dimensional theoretical analysis of the thermal and fluid processes involved in the ablation process. The results indicate the existence of a very thin melted zone below the surface and suggest that the rim is formed by the high pressure plasma producing a pressure-driven fluid motion of the molten material outwards from the centre of the crater. The numerical solutions of pressure-driven fluid motion of the thin melt demonstrate that the melt can flow to the crater edge and form a rim within the first nanoseconds of the ablation process. The possibility that a tall rim can be formed during the initial stages of the plasma is suggestive that the rim may tilt outwards towards the low pressure region creating a resolidified melt splash as observed in the experiments. The possibility of controlling or suppressing the rim formation is discussed also.

Electrochemical discharge machining (ECDM) involves the electrolytic formation of a gas film at a tool electrode with high current density discharges and Joule heating for local material heating and removal. The ECDM process is ideally suited for low density glass through-hole machining for applications such as fluidic interconnection. In this paper, we describe a simple and robust ECDM cell arrangement and present optimum conditions for rapid and reproducible through-hole machining in both 500 mu m thick and fragile 180 mu m thin borosilicate glass substrates. Both anodic and cathodic methods were evaluated and the results offer additional insight into the complex and polarity-dependent mechanisms involved in the ECDM process. The anodic process produces unique spherical cavity microstructures, presenting a new capability for glass microfabrication.

The need for a flexible, low-cost and high-throughput process for the fabrication of a nano/micro glass-based micro fluidic device is becoming increasingly acute as the bio-MEMS industry is expanding very fast. In this study, repetitive-pass milling with a focused ion beam (FIB) was used for maskless and resistless fabrication of glassy carbon (GC) molds, which will then be the primary elements in the mass production of nano/micro glass devices by mold replication processes. The aim of the study is to establish basic process conditions and to investigate possible problems that occur during both FIB milling of GC and thermal imprint of glasses. First, the milled depth–beam dwell time curve for GC was investigated experimentally, and the relationship between the areal ion dose and the milled depth was formulated for application to the design of mold parts using FIB milling. Then, GC molds were produced and used for imprinting glasses to make micro fluidic parts. Surface contamination due to the FIB milling could be eliminated by a vacuum heat treatment at 1400 °C for 10 min. Finally, a dimensional mismatch arising from a thermal expansion coefficient mismatch between the GC mold and the glass materials was discussed.

Perylene molecules have been successfully implanted onto borosilicate glass plates, forming fluorescent features of 420 nm in diameter, using a method involving laser induced molecular micro-jet ejection through a water layer. The technique utilises a polymer source film in which perylene molecules are dispersed, a borosilicate glass substrate as a target and a pulsed laser. The space gap between the source film and the target is filled with liquid water. Perylene molecules dispersed in the polymer source films are photo-excited using 4-ns laser pulses resulting in the ejection of the molecules from the source matrix after which they become implanted into the target after passing through the water layer. This new advanced implantation method, using a laser induced molecular micro-jet through water, gives fine spatial control for fixing functional organic molecules in a designated region on hard dielectric materials and will have application in the fabrication of molecular devices, molecular sensors, and opto-electronics.

The scope of this work is to report the results of microwave insertion loss measurements as a function of frequency and composition of some selected phosphate glasses containing transition metal oxide. Borosilicate glasses are commonly used in microwave travelling wave tubes, microwave windows, etc. They present very high microwave transmittance (low microwave insertion loss) in a certain frequency domain, which must be a very important feature for microwave power applications. The works regarding microwave insertion loss studies in glass systems are found to be very scarce at present. The results show that there is a possibility of our glasses being used in windows for high-power microwave tubes, once the microwave signal insertion loss at the frequencies of 8.3 and 11.8 GHz attains values nearly 0 dB. The results show that it is possible to control the 9.7 GHz absorption peak, by increasing the transition metal oxide concentration in the glass, above a certain value. The transmittance technique can also be used for the study of a greatest variety of materials.

Optical waveguides were prepared by the incorporation of silver or copper ions into soda-lime silicate and borosilicate glass substrates using a classical staining process. The waveguides were colorless and optically clear, indicating that silver and copper metal nanoparticles and Cu2O nanoparticles that cause coloration of glasses were not formed. The increase in the refractive index at 633 nm reached 4×10-2 and 1×10-2 for the silver-doped and copper-doped waveguide layers, respectively. The ion distribution measured by energy dispersion X-ray analysis showed that the silver and copper ions reached depths of 5 and 20 µm, respectively, in the substrates. Single-mode propagations at 633 nm and 1.54 µm were observed for both silver-doped and copper-doped waveguides.

High size dispersion, large average radius of quantum dot and low-volume ratio has been a major hurdle in the development of quantum dot based devices. In the present paper, we have grown CdTe quantum dots in a borosilicate glass matrix using a two-step annealing method. Results of optical characterization and the theoretical model of absorption spectra have shown that quantum dots grown using two-step annealing have lower average radius, lesser size dispersion, higher volume ratio and higher decrease in bulk free energy as compared to quantum dots grown conventionally.

Two glass samples were prepared according to the molar formula (20%X–40%B2O3–40%SiO2), where X = CaO or CaF2. The glass was melted at 1300°C for 3 h until homogenous glass was obtained. The glass samples were heat-treated at 700°C for 2 h and at 850°C for different times. The green glass obtained has low dielectric constant and positive magnetic susceptibility. The molar volume, scanning electron microscope and differential thermal analysis studies showed that the crystallization rate increases with an increase in the sintering time. The replacement of CaO by CaF2 improves the physical properties of the glass. The existence of fluorine ions increases the electrical conductivity, magnetic susceptibility, molar volume, dielectric constant and effective overall reaction rate (κ). All measured properties have a random behaviour with sintering time due to phase separation and asymmetry of crystallization.

Atomic force microscopy (AFM) was used to study the morphology and coagulation of human blood cells in contact with solid surfaces. Blood was extracted from the veins of healthy adult donors and the samples were used immediately after extraction, deposited either on borosilicate glass or diamond substrates. Some blood samples were anti-coagulated by adding heparin for single cell AFM imaging. No chemicals were used for attaching or immobilizing the cells. The diamond substrates were produced by chemical vapour deposition (CVD diamond) using a hot-filament CVD system fed with ethanol highly diluted in hydrogen. AFM imaging of isolated cells (anti-coagulated by heparin) was only possible on the glass substrates due to the lack of adherence of the cells to the diamond surface. The coagulation results suggest that blood clotting on diamond produces a less rough surface than blood clotting on glass.

Planar waveguides have been formed by the electric field assisted diffusion of copper ions from a metallic copper film into a borosilicate glass (Corning 7740). The waveguides have been analysed using conventional prism coupling techniques and have been compared with the electric field assisted diffusion of silver into the same glass type. The measured refractive index profiles for copper guides are shown to have nearly Fermi function shapes, which are consistent with the theory of field assisted ion diffusion in glass. It is shown, however, that the guide depth formed by copper or silver ions is larger than that predicted by calculations based on the nominal composition, possibly indicating that only a fraction of the sodium ions within the glass are mobile. Annealing experiments have been performed on the guides in order to determine the copper self-diffusion coefficient in the glass. The coefficients are extracted from the data by fitting a non-linear diffusion equation model of ion motion in glass to the experimental profiles.

This paper reports on a new model to investigate the femtosecond laser ablation of dielectrics by considering the time and space dependent optical properties of highly ionized dielectrics. A quantum treatment is employed to determine the free electron heating and the free electron relaxation time in the dense plasma. The proposed model greatly improves the prediction precision of ablation depth and can predict the crater shape of femtosecond laser ablation of dielectrics. The predicted ablation depths are in agreement with published experimental data for the example of barium aluminium borosilicate. Some interesting phenomena observed experimentally can be well explained by the proposed model.

Reversible tubing connections for glass micro-fluidic systems are realized using electro-chemical discharge machining of three-dimensional glass vias. The connections reversibly connect standard sized plastic tubing to holes in borosilicate microscope slides. Tubing connections are demonstrated on a sealed, micro-fluidic channel which is fabricated between two glass slides using SU-8. The connections are experimentally tested to withstand up to 30 psi (~206 kPa) of air pressure without leaking.

A quick and easy method for monitoring phase separation in glasses based on transmittance spectra is described. The spectra are recorded after different intervals during heat treatment of doped or undoped glass samples and chromaticity x-and y-values are obtained from them. The results can be depicted graphically in x/y chromaticity diagrams for various doping levels and/or exposure times. The influence of dopant ions on the phase separation becomes readily evident when the results for doped and undoped samples of the same host glass composition are compared. The glass samples presented are ternary sodium borosilicate glasses; the effect of doping with Nd3+ and P5+ is discussed.

We report on our work on determining the structure of oxide glasses using laser ionization time of flight mass spectrometry. This technique is especially suitable for investigation of the intermediate-range order in glasses, where it can measure the presence and relative abundance of mesounits composed of 7–20 or more atoms. After introducing the experimental aspects and caveats of this new spectroscopy, we discuss the application of the instrument to a variety of heavy-metal oxide glass families. We separate our networks into those that have superstructural networks and those that show highly fragmented ones, including our studies of lead and bismuth borates, lead silicates, lead vanadates, and bismuth gallates. We also analyse our spectra for evidence of mixing in lead borosilicates, and to clarify the sharing of cations in sodium-doped lead borosilicates.

Commercial thick-film resistor pastes were printed on and embedded in cordierite+borosilicate glass low-temperature co-firable ceramic (LTCC) substrates. The electrical properties of the resistors were found to depend on the final microstructure. Anorthite crystals were produced by the interaction between the substrates and glass composition of the resistor films at boundaries. The anorthite crystals grown into the substrate and the resistor layer increased the overall resistance. Sedimentation of the conductive particles and glass migrating to the substrates decreased the resistor thickness during sintering. Conductive particles in the resistor films flocculated after firing at 850° and 900°C. Formation of anorthite crystals, conductive particle sedimentation, glass migration, and inter-diffusion were determined to be three major factors determining film resistivity.

Lead borosilicate glasses having general formulae (PbO)0.5 −x(SiO2)0.5(B2O3)x with 0.0 ≤ x ≤ 0.4 and (PbO)0.5(SiO2)0.5 −y(B2O3)y with 0.0 ≤ y ≤ 0.5 have been prepared by a conventional melt–quench method and characterized by 29 Si, 11 B magic angle spinning (MAS) NMR techniques and infrared spectroscopy, as regards their structural features. From 29 Si NMR results, it has been inferred that with increasing concentration of boron oxide, (PbO)0.5 −x(SiO2)0.5(B2O3)x glasses exhibit a systematic increase in the number of Q4 structural units of Si at the expense of Q2 structural units, along with the formation of Si–O–B linkages. On the other hand, for (PbO)0.5(SiO2)0.5−y(B2O3)y glasses, there is no direct interaction between SiO2and B2O3 in the glass network, as revealed by the 29 Si MAS NMR studies. Boron exists in both trigonal and tetrahedral configurations for these two series of glasses and for the (PbO)0.5(SiO2)0.5−y(B2O3)y series of glasses; the relative concentration of these two structural units remains almost constant with increasing B2O3 concentration. In contrast, for (PbO)0.5−x(SiO2)0.5(B2O3)x glasses, there is a slight increase in the number of BO3 structural units above x = 0.2, as there is a competition between SiO2 and B2O3 for interaction with Pb2+, thereby leading to the formation of BO3 structural units. For both series of glasses, the thermal expansion coefficient is found to decrease with increasing B2O3 concentration, the effect being more pronounced for the (PbO)0.5 −x(SiO2)0.5(B2O3)x series of glasses due to the increased concentration of Q4structural units of silicon and better cross-linking as a result of the formation of Si–O–B-type linkages.

Owing to the interaction between lead borosilicate glass and AlN, the commercial resistor pastes which were developed for Al2O3 substrates are not applicable to AlN substrates. The conventional solution is to develop alternate glass compositions such as alkaline earth borosilicate glass to optimize compatibility with the AlN substrates. In this study, an additive-doping method was adopted to solve the problem of incompatibility between AlN substrates and resistor pastes. The Al2O3 and MnO2 powders were deliberately introduced into the as-received resistor pastes, and the interaction between AlN and glass was thus reduced or avoided. With the optimal control of sintering conditions, it is possible to produce stable thick film resistors on AlN substrates with the temperature coefficient of resistance values of less than ±100 ppm/°C.

Glasses doped with Sm2O3 were prepared by conventional melt-quench technique. The glasses were characterized by XRD, density and glass transition temperature. These glasses were converted into glass-ceramic by two stage heat treatment schedule. Photoluminescence measurement was carried out for glasses and glass-ceramics. The glass samples when excited with 402 nm as an excitation wavelength, the luminescence spectra gives three bands at 562 nm, 601 nm and 647 nm due to 4G5/2 → 6H5/2, 4G5/2 → 6H7/2 and 4G5/2 → 6H9/2 transitions, respectively. The current study indicates that these sodium borosilicate glasses show apparent change in emission intensity when they are converted into glass ceramics. The overall study suggests that these glasses can be used for LED application.

The addition of Gadolinium (Gd)-based salt, specially GdCl3, in the Water Cherenkov Detectors (WCDs) enhances the sensitivity to neutrino detection. However, the unwanted Cl-based byproducts, significantly reduces the transparency of water and sensitivity of WCDs. An alternative method, to introduce Gd-ions in the WCDs, is through Gd-release from a custom designed Gd-doped glass, when in contact with water. This can potentially eliminate the use of Gd-based salts and byproducts. In this work, we report the Gd-ions release for a Gd-doped peralkaline (Na/Al > 1) borosilicate glass, which closely represents photomultiplier tube (PMT) glass composition used in WCDs. The purpose of the paper is to show that the Gd-ion release from a custom designed glass in the form of beads or powders is feasible and could be used as a controlled Gd-source in future WCDs to enhance neutrino detection. In addition, we present our results of Gd-solubility in the base glass composition.

Thinning of silicon wafers and reduction of kerf loss can minimize the manufacturing costs of semiconductor products. Currently, the volume of kerf loss is about the same as the volume of the wafer itself. Therefore, we study slicing techniques for silicon wafers that result in reduced kerf loss by using an ultrafine wire tool and fine abrasive grains. As a first step, grooving characteristics using an ultrafine tungsten wire tool and fine abrasive grains are investigated in this paper. A borosilicate glass is used as the work material. The main conclusions are as follows: Precision machining using ultrafine wire tool is possible and the kerf loss decreases because the groove width decreases. However, a larger diameter of the wire tool results in a deeper groove. A faster relative speed produces a shorter wire tool lifetime, but a deeper groove. To supply enough abrasive grains to the machined portion, it is necessary to use abrasive grains having a suitable particle size for the specific diameter of the ultrafine wire tool.

Glass nanoneedles are important tools for injecting drugs and other materials into living cells. Although we know a great deal about the mechanical properties of glass structures at the millimeter scale, relatively little is known at the nanoscale. Here we investigate the mechanical performance of hollow glass nanoneedles by nanorobotic in situ manipulation inside SEM. Quartz and borosilicate nanoneedles fabricated from glass capillaries are assembled on the nanorobotic characterization system inside SEM and their behaviors during bending and recovery are studied in situ. The result indicates the glass nanoneedle could present a large elastic bending deformation (>90°). Specifically, the quartz nanoneedle takes on larger bending strength and its deformation can recover totally. In contrast, the borosilicate nanoneedle presents more flexible and still 20% of deformation is remained after 3 months. These results not only enhances our basic understanding on nanoglass materials but also provides references for practical nanomanipulation applications.

Functionally glass materials have been widely applied in various technological applications remarkably due to their optoelectric properties. In this present study, the glass was prepared from leaching product of local silica sands. Bi2O3 and Na2CO3 were added to reduce the melting point of silica sand to form silica glass and Fe2O3/B2O3 was incorporated to examine its effect on the crystal structure, morphology, and light-induced dielectric properties of the borosilicate-based fuctional glass. The characterizations were conducted by means of Differential Thermal Analyses (DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and capacitance meter under the influence of light intensity. The XRD pattern shows the absence of any sharp diffraction peak indicates the amorphous state of the borosilicate glass. While the SEM image shows that the borosilicate glass exhibited amorphous characteristic. Furthermore, the increasing of Fe2O3 tends to reduce the dielectric constant. On the other hand, the increase of light intensity increase the dielectric constant with a step like properties.

Recently, it was found that the multi-component glass a-BaO-Al2O3-SiO2 exhibits unusual magnetic properties at very low temperatures. Thus the question arises whether this is a specialty of that particular glass or a more general phenomenon. We report here on our studies of the magnetic-field dependence of the dielectric properties of the borosilicate glass BK7 which contains only a negligible amount of magnetic impurities. Since this glass also responds sensitively to magnetic fields, our investigations demonstrate that the reaction of glasses to magnetic fields is not caused by magnetic impurities but reflects a more general phenomenon. In addition, we have observed that the variation of the dielectric constant and the loss angle with magnetic field depend on the amplitude of the electric field that is used to measure the glass capacitance. We present the data and discuss possible origins of the magnetic-field phenomena in non-magnetic glasses.

The nucleation and growth of Cd1-xZnxS and CdSxSe1-x nanocrystals in borosilicate glass are investigated through optical absorption and resonant Raman scattering measurements. The optical absorption spectra are interpreted with the help of a quantized-state effective-mass model applied for heterogeneous and homogeneous nucleation of nanocrystals. Stoichiometry changes of the particles during the growth stage are monitored by resonant Raman measurements. The findings indicate that the formation of Cd1-xZnxS particles involves a stage of homogeneous nucleation and then a rapid transition to ripening. No growth is observed. CdSxSe1-x particles undergo heterogeneous nucleation and growth simultaneously with a gradual transition into the ripening stage.

A recent study identified boron, sodium, aluminium and silicon as the dominant impurities in triple point of water (TPW) cells. These results suggest that borosilicate glass is a less than ideal container as it is the most likely source of the contaminating elements. An estimate for the rate of change of the equilibrium temperature of TPW cells is presented using results recently obtained at the National Research Council of Canada (NRC) and supplemented by those reported in 1982 by Furukawa and Bigge of the US National Institute of Standards and Technology (NIST). An analysis of the two data sets suggests that a decrease of 4 µK per year is appropriate in describing the average behaviour of TPW cells. The conclusion is speculative in that the behaviour of the various cells has not been monitored over a period of time to track the nature of the changes. Rather, the analysis assumes that the changes have occurred continuously and linearly with time.