Flat Glass Research Articles

UTHP spectrometer: an ultra-thin and high-performance imaging spectrometer for ocean color remote sensing in broadband

The principle of ocean color detection involves using satellite sensors to capture variations in received signals, which are subsequently analyzed to infer the concentrations of various components responsible for ocean color changes. In recent years, significant research advancements have been achieved, centered on the development of ocean color detectors and the analysis of the resulting data. We have developed an innovative ultra-thin high-performance (UTHP) scanning imaging spectrometer for ocean color remote sensing across the near ultraviolet-visible-near infrared (NUV-VIS-NIR) spectrum. This spectrometer overcomes the bulkiness of conventional equipment by integrating a waveguide platform that replaces traditional optical elements with a single flat glass panel, featuring curved surfaces and high-reflectivity coatings to perform essential optical functions. We believe this to be a novel design that greatly reduces the size and weight of the device, making it highly suitable for deployment on various platforms, including aircraft and satellites. The optical system underwent extensive testing, including simulations using Zemax software and physical prototyping, achieving a spectral resolution of less than 3 nm across the 400-1000 nm waveband while maintaining low distortion. The UTHP spectrometer’s compactness, lightweight design, and exceptional performance mark a significant advancement in imaging spectrometry, with the potential to transform remote sensing by providing more efficient, accessible methods for studying expansive oceanic regions.

Non-Circular Cross-Section Fibres for Composite Reinforcement—A Review with a Focus on Flat Glass Fibres

Glass fibre reinforcements form the backbone of the composites industry. Today, glass fibre products account for more than 95% of the fibre reinforcements used in the composites industry. Since the first commercialisation of glass fibres for composite reinforcement in the 1930s, the cross-sectional shape of glass fibres has remained exclusively circular. However, many of the other types of fibre reinforcement have a non-circular cross section (NCCS). This paper reviews the available knowledge on the production of NCCS glass fibres and some of the possibilities that such fibres offer to enhance the performance of glass reinforced polymer composites. The three parts of the review focus on early research work on different shapes of glass fibre, the developments leading to industrial-level production of NCCS glass fibres, and the more recent data available on the influence of the available commercially produced NCCS flat glass fibres on composite performance. It Is concluded that the continued development of NCCS glass fibres may offer interesting potential to generate composites with increased performance and may also enable further tailoring of composite performance to enable new applications to be developed.

The Acoustic Emission Testing in the Evaluation of Fracture Toughness of Brittle Materials.

Evaluating the fracture resistance of dental ceramics is essential for assessing their behavior. This study aimed to validate a custom load-to-fracture test for assessing fracture strength compared to a conventional method. Acoustic emission testing, a non-destructive (ND) lab test, was employed to evaluate the fracture toughness (FT) of brittle materials by capturing sound waves generated by crack formation in failing samples. A total of 130 samples, divided into three types (glass sheets, zirconia sheets, and monolithic zirconia crowns), were tested. The fracture loads were measured using both custom and conventional methods. The mean fracture loads for glass sheets were 650.46 N ± 110.38 (custom) compared to 691.41 N ± 155.92 (conventional). For zirconia sheets, the values were 95.25 N ± 7.78 (custom) vs 112.75 N ± 31.26 (conventional). Monolithic zirconia crowns showed mean fracture loads of 1108.99 N ± 327.89 (custom) compared to 1292.52 N ± 271.42 (conventional). Statistically significant differences were evident in all three types, indicating lower values with custom testing for all samples. The custom testing demonstrated an advantage in identifying cracks at lower loads, thereby enhancing the accuracy of fracture load values. Despite its limitations, the study suggests that the custom setup could be a viable alternative to conventional fracture load testing of brittle materials. However, further testing with more materials is recommended to enhance the results' accuracy and generalizability. The findings indicate that the custom load-to-fracture test can provide more accurate measurements of FT in dental ceramics, which is crucial for predicting their clinical performance and longevity. How to cite this article: Haddad C, Eng JG, Zoghbi AE. The Acoustic Emission Testing in the Evaluation of Fracture Toughness of Brittle Materials. J Contemp Dent Pract 2024;25(7):617-623.

Mechanical and micro-structural characterization of biodegradable coir fiber–glass sheet–charcoal reinforced polymer composite: an experimental approach

In the present investigation, the combined influence of coir, glass fibers and charcoal content on the mechanical properties of epoxy-based hybrid composites has been explored, providing insights for the potential development of advanced materials with tailored performance characteristics. Through a systematic analysis of the mechanical properties (tensile strength, Young's modulus, flexural strength, flexural modulus, and Brinell hardness number), various composite formulations were evaluated to discern their performance characteristics. The study reveals significant variations in mechanical properties across different composite configurations, highlighting the critical role of fiber type and charcoal content in determining the materials’ performance. Notably, composites featuring alternating layers of glass and coir fibers exhibit superior tensile and flexural strengths, underscoring the synergistic effects of hybridization. Conversely, the introduction of charcoal as a reinforcement agent leads to deterioration in the mechanical properties, indicating a trade-off between the reinforcement and other desirable attributes. These findings offer valuable insights for the strategic design and engineering of advanced materials tailored to specific applications, paving the way for the development of high-performance epoxy-based hybrid composites with enhanced mechanical properties and durability.

Explosion disaster at a pharmaceutical facility in Visakhapatnam, India

An industrial accident at a red category Escientia Advanced Sciences Pharmaceutical Company at Anakapalli district on 21st August claimed 17 lives due to blast injuries and 36 others sustained various degrees of thermal injuries. A Methyl-tert butyl ether (MTBE) heavy solvent leak while transiting from the second floor to the storage tank on the ground floor resulted in a vapour cloud around the power panel located there and ignited. The fire then spread through the ducts of the air handling unit to four other modules in the production block. Thick smoke and flames engulfed the facility, hampering rescue operations. 14 fire tenders and 50 fire personnel fought the blaze for an hour before arresting the blaze and preventing it from reaching the higher floors. Skylift, boom lifts and cranes were deployed by firefighters to break the plate glass windows and extricate 13 trapped workers. Around 380 employees work two shifts at the plant and most of them escaped because they were on lunch break when the explosion started the conflagration. The injured were treated at the NTR and private hospital at Anakapalli and the evacuated to tertiary hospital in the city and the Government Medical College at Visakhapatnam. No trauma or burns centre are available at the special economic zone housing the pharma city where 120 industrial accidents and equivalent number of deaths have been reported over the past five years. A detailed enquiry has been ordered into the incident by the State Government.

Investigation of an Innovative Roll-to-Plate (R2P) Hot-Embossing Process for Microstructure Arrays of Infrared Glass

The roller-to-plate (R2P) hot-embossing process is an effective, low-cost method for producing high-quality micro-/nano-optical components. In the field of night vision applications, the fabrication of chalcogenide glass microstructures is emerging as a promising alternative to traditional infrared glass. This trend is driven by the potential of chalcogenide glass to surpass conventional materials in terms of performance. However, the development of R2P hot embossing faces challenges, such as the high cost of curved mold manufacturing, the reliance on roll-to-roll processes for nano hot embossing, the limitations of plastic materials, and the unclear viscoelastic properties of infrared glass. In this study, a novel R2P hot-embossing process was developed to fabricate flat chalcogenide glass structures. The key parameters, such as roller temperature, speed, and embossing pressure, were investigated to understand their impact on the glass-filling performance. The deformation mechanism of the glass microstructures was also analyzed. The experimental results show that the R2P hot-embossing method offers excellent reproducibility, achieving a maximum filling rate of 96% and an average roughness deviation of 8.36 nm. The increase in the roller temperature and embossing force increased the filling height of the glass microstructure arrays, while an increase in the roller speed decreased the filling height. Different embossing methods, including variations in speed, temperature, and force, are summarized to analyze the structural changes during embossing. This study provides a foundation and a basis for future research on the roller-to-plate hot embossing process.

Z-Scheme Ag2S-Ag-In2O3 Heterostructure with Efficient Antibiotics Removal under Natural Sunlight.

The widespread distribution of antibiotics in natural waters is a great threat to human health. Photocatalytic degradation is an environmentally friendly technology to remediate antibiotic-polluted waters, driven by endless solar energy. Herein, a Z-scheme Ag2S-Ag-In2O3 heterostructure photocatalyst is prepared to remove antibiotics under environmental conditions. Under natural sunlight (light intensity: ∼78 mW/cm2) irradiation, the optimal Ag2S-Ag-In2O3 (10-ASAIO) exhibits considerable performance for decomposing diverse antibiotics, including norfloxacin (NOR), tetracycline hydrochloride, sulfisoxazole, ciprofloxacin, chlortetracycline hydrochloride, and ofloxacin. The NOR photodegradation rate constant of 10-ASAIO reaches 0.025 min-1, which is 12.50, 5.00, and 6.25 times higher than that of In2O3 (0.002 min-1), Ag-In2O3 (0.005 min-1), and Ag2S-In2O3 (0.004 min-1), respectively. This performance of the 10-ASAIO photocatalyst for decomposing NOR under natural sunlight exceeds most of the previously reported photocatalysts under a xenon lamp. Particularly, due to the intermittency of natural sunlight, a light-emitting diode (LED) lamp (light intensity: 5.1 mW/cm2) is also used as a light source, and 72.20% of NOR can be degraded with irradiation for 12 h. The effects of many water characteristics (water bodies, coexisting inorganic anions, pH, and humic acid) on the degradation performance of 10-ASAIO have been investigated, which exhibits stable degradation efficiency in variable aquatic environments. A 10-ASAIO catalyst-coated frosted glass sheet is fabricated to settle the problem of recovery of powder photocatalysts, and the immobilized catalyst shows outstanding activity and stability to decompose NOR. The photocatalytic mechanism and pathway of degrading NOR over 10-ASAIO have also been systemically investigated and proposed. The ecotoxicity (phytotoxicity and biotoxicity) of the 10-ASAIO photocatalyst and treated NOR solution have been tested by their toxic effects on cabbage seeds and Staphylococcus aureus (S. aureus). This work provides a feasible photocatalytic system for environmental pollutant remediation under natural sunlight or an LED lamp.

Blocking of Gas–Liquid Coalescing Filters with Accumulated Oil during the On–Off Operation of a Filtration System

The study aims to eliminate the effect of coalescing filter blocking due to on–off operation by changing the wetting properties of the non-woven fiberglass filter media through their chemical modification with the use of a polydimethylsiloxane (PDMS) solution in hexane and a few commercial products that give the surface oleophobic properties. The best results—high separation efficiency, no redispersion of droplets at the outlet, and low flow resistance—were obtained for materials coated by immersion in a 0.2% PDMS solution, for which a reduction in oleophilicity was found, but the material was not oleophobic and still moderately wetted with the test liquid. The corresponding static contact angle with the VG-46 rotary compressor oil measured on the flat borosilicate glass wafer made of the same material as the fiberglass media was equal to 54° for the PDMS dip-coated surface. Moreover, the good stability of the applied polymer on the material surface was confirmed by the SEM imaging, the FTIR analysis, and maintaining a high performance in multiple tests run for a single coalescing element.

Highly efficient photocatalysis-Fenton degradation of antibiotics and phenol over sulfidated FeOCl under natural sunlight illumination

Sulfidated FeOCl is prepared as a heterogeneous photo-Fenton catalyst. And the surface sulfidation of FeOCl can remarkably accelerate the photoinduced charge separation and transfer, while also increase Fe2+/Fe3+ atomic ratio, leading to the boosted photo-Fenton activity in the presence of H2O2. Under irradiation of natural sunlight (light intensity: ∼80 mW·cm−2), over 10 mg sulfidated FeOCl catalyst with using 20 μL 15 % H2O2, 91.2 % of ofloxacin solution (50 mg·L−1) and 97.5 % of sulfisoxazole solution (60 mg·L−1) can be degraded in 80 min, and 99.6 % of phenol solution (625 mg·L−1) is decomposed in 4 h. Under irradiation of a white Light-Emitting Diode (LED) lamp (light intensity: 5 mW·cm−2), 99.8 % of ofloxacin solution is decomposed after treatment for 4 h. Moreover, this photo-Fenton degradation system displays a stable activity in a wide range of pH (1−10), diverse water bodies, and various coexisting ions with concertation from 1 mM to 500 mM. Moreover, sulfidated FeOCl catalyst coated on a frosted glass sheet exhibits excellent stability for degrading ofloxacin even in seven continuous cycles. Particularly, the non-toxicity of the treated ofloxacin, sulfisoxazole, and phenol solution, have been proven by testing their toxic effects on cabbage seed, bacteria, and human embryonic kidney cell, respectively.

Anti‐glare performance of sol‐gel‐derived spray coatings prepared with various water‐to‐alkoxide ratios

AbstractWe fabricated anti‐glare (AG) coatings on glass sheets by spraying alkoxide‐derived silica sols and demonstrated that the water‐to‐alkoxide ratio is one of the key factors for improving AG performance and sol stability. We synthesized silica sols using tetraethylorthosilicate (TEOS), water, nitric acid, and denatured ethanol and sprayed them on sheets of chemically strengthened glass. The molar ratios of water to TEOS (r) were 3, 7, and 14. The sol with r = 7 provided a higher arithmetic‐mean height (Sa), smaller autocorrelation length (Sal), and better optical properties (lower gloss, higher haze, and lower sparkle level) than the sol with r = 3. An excessive amount of water at r = 14 yielded a large Sal and a high sparkle level. As the storage time of the sols increased, higher r values caused a more pronounced increase in Sa. Although none of the sols showed noticeable temporal changes during dynamic light scattering measurements, solutions with higher r values exhibited a more remarkable reduction in the retention time during liquid chromatography with a styrene‐divinylbenzene matrix. Hence, an excessive amount of water was thought to cause hydrophilization of the polymerized species during storage.

Novel Retrofitting Technique for Beam by External Wrapped with Glass Fiber and Internally Embedded Damper System for Sustainable Construction

Abstract Reinforced concrete structures are often exposed to extreme loads, such as those from sudden and accidental impacts. This has led to an increasing interest in strengthening these structures, improving their fatigue performance, and extending their service life, particularly for components like beams. A more sustainable approach to maintaining their functionality involves strengthening and repairing damaged components. Therefore, glass fiber polymers are ideal reinforcements for retrofitting due to their high tensile strength and low cost compared to other polymer substitutes This paper presents the performance of plain concrete beams reinforced externally with glass fiber sheets (GFS) and dampers embedded internally. A unique methodology has been adopted to improve the adhesion between the fiber glass sheets (GFS) and the concrete surface. Two adhesive components utilized are epoxy resin (ER) and epoxy hardener (EH), mixed in a ratio of 9:1. Internally embedded dampers are devices used to resist lateral forces on structures, particularly during impact or sudden loading. The adopted damper technique involves incorporating chopped Glass Fiber during the casting process of the dampers. These dampers are subsequently embedded into beams at point of failure. After the curing of 28 days, all the cast beam compositions undergo flexural test, and dampers are tested for compressive strength. After the dampers have undergone compression testing, a microstructural analysis is conducted using SEM (Scanning Electron Microscope). For further details on stress formation in beams, finite element analysis of Ansys is used to model beams for all beam compositions. Also, sustainability goals are addressed by reducing cement usage in construction by introducing retrofitting in older buildings and using this system to improve the design of newer buildings by reducing overall section sizes

Dynamics of a single cavitation bubble near an oscillating boundary

Cavitation and its effects are well investigated, especially single bubble cavitation and its collapse near rigid and elastic boundaries. In our current article, we investigated novel experiments of a single cavitation bubble near an oscillatory boundary. We generated the cavitation bubble by laser focusing in water. A flat glass plate was fixed to the shaft of the magnetostriction oscillator coil. We investigated the dynamics of bubbles at two relative wall distances (ratio of the distance between the bubble center and plate surface to the maximum radius of the bubble) of the bubble from the glass plate in combination with four modes of oscillation. Each mode has specific frequency and amplitude of oscillation. The high-speed camera captured the dynamics of the bubble using the back-illumination method with a framing rate of 120Kfps and simultaneously we used an optical CMOS sensor to measure the oscillation of the glass plate. We presented a clear comparison among the bubble dynamics near stationary and oscillating plates with parameters such as oscillating modes and direction. We correlated the dynamics of the bubble with the motion of the plate. In addition, we highlighted the differences including the characteristics of bubble shape and jetting that occurred during the collapse phase. The comparison of the time histories of the bubble’s equivalent size postulated that the bubble’s collapse times vary significantly in some cases compared to the bubble’s dynamics near the stationary plate. In all cases, we noticed the shortening of the bubble’s collapsing time, i.e. accelerated collapses. In our findings, we noticed a collapse times reduction of about 4–15%. Our finding signifies the importance of introducing the oscillation of the boundaries to obtain effective energy concentration over the time during the collapse. Our study also suggests that forced oscillation of boundaries is undesirable for destructive cavitation effects. The method we suggested for the manipulation of bubble dynamics holds potential for enhancing the efficiency of applications such as lithotripsy in biomedical devices, actuation and micro pumping in microfluidic devices, and effective semiconductor surface cleaning. Not but least, obtained results can be used as benchmark in future for validating numerical methods.

Enhancing glass-ionomer cements with flake-shaped glass: A new frontier in dental restoration.

This study aims to investigate whether the combined use of thin sheet glass (FSG) and polyurethane acrylate (PUA) can enhance the mechanical properties and biocompatibility of glass ionomer cements (GICs) to improve the overall performance of commercial GICs. In this study, an innovative approach was employed by incorporating diluents and photoinitiators into PUA to develop a novel light-curable PUA material. The PUA was then used to modify the GIC to obtain PUA-modified GIC. Subsequently, physical and chemical methods were employed to corrode and chemically modify the glass fiber surface to acquire dried thin sheet glass (FSG). Different proportions of FSG (10%, 20%, and 30% by mass) were mixed with PUA-GIC to obtain FSG-PUA modified GIC. Mechanical and biocompatibility tests were conducted on regular GIC, PUA-GIC, resin-modified glass ionomer cement (RMGIC), and various proportions of FSG-PUA-GIC materials, including flexural strength, surface hardness, water absorption rate, solubility, shear strength, compressive strength (CS), in vitro cytotoxicity, as well as short-term oral toxicity and subcutaneous implantation trials. A novel FSG-PUA modified GIC was successfully prepared, which not only retained the excellent biocompatibility and fluoride ion release capacity of the original GIC but also significantly enhanced its mechanical strength and durability. The application of this innovative method provides a new direction for the development of dental restorative materials, particularly in addressing the shortcomings of GICs in terms of mechanical performance. The addition of FSG notably increased the flexural strength and surface hardness of GICs, especially at a 20% additive level, demonstrating superior performance compared with standard Fuji IX (F9) and slightly better than RMGIC. Water absorption rate and solubility initially decreased and then increased with an increase in FSG content, and significantly outperformed F9 and RMGIC at 10% and 20% additive levels. Shear strength and CS decreased with an increase in FSG content but remained superior to commercial groups. Material incubation with cells in vitro for 24-48 h showed no significant impact on cell viability, with cell viability exceeding 90%. Short-term oral toxicity tests demonstrated good biocompatibility of the material, and subcutaneous implant trials did not observe any significant inflammation or pathological changes within 12 weeks of observation. The use of FSG-PUA materials effectively enhances the mechanical properties of GIC materials, demonstrating excellent biocompatibility and significant potential as dental restorative materials. Among them, the 20% FSG-PUA modified GICs exhibited significantly superior flexural strength, surface hardness, shear strength, water absorption, and solubility compared with F9 and slightly surpassing RMGIC, showcasing the best mechanical performance.

Hybridizing Shear-Stiffening Gel and Chemically-Strengthened Ultrathin Glass Sheets for Flexible Impact-Resistant Armor.

Traditional anti-impact armors and shields are normally made of stiff and hard materials and therefore deficient in flexibility. This greatly limits their applications in protecting objects with complex geometries or significant deformability. Flexible armors can be developed with the application of hard platelets and soft materials, but the lower rigidity of the flexible armors renders them incapable of providing sufficient resistance against impact attacks. To address the inherent conflict between flexibility and impact resistance in traditional armors, here, a composite is developed by hybridizing a shear-stiffening gel as the matrix and chemically-strengthened ultrathin glass sheets (CSGS) as the reinforcement. The resulting laminate, termed PCCL, exhibits both high flexibility and high impact resistance. Specifically, at low strain rates, the high ductility of the gel combined with the high flexural strength of the CSGS enables the PCCL to undergo considerable deformation; at high strain rates, on the other hand, the shear stiffening behavior of the gel matrix endows the PCCL with excellent impact resistance manifested by its high performance in energy absorption and high rigidity. With the combination of high flexibility and high impact resistance, the PCCL is demonstrated to be an ideal armor for protecting curved vulnerable objects from impact attacks.

Optical Interferometric Device for Rapid and Specific Detection of Biological Cells.

Here, we report a rapid and accurate optical method for detecting cells from liquid samples in a label-free manner. The working principle of the method is based on the interference of parts of a conical laser beam, coming from a single-mode optical fiber directly, and reflected from a flat glass surface. The glass is functionalized by antibodies against the cells to be detected from the liquid sample. Cells bound to that surface modify the reflected beam, and hence, change the resulting interference pattern, too. By registering and interpreting the variation in the image, the presence of cells from the sample can be detected. As for a demonstration, cell suspensions from a U937 cell line were used in glass chambers functionalized by antibodies (TMG6-5 (mIgG1)) to which the cells specifically bind. The limit of detection (LOD) of the method was also estimated. This proof-of-concept setup offers a cost-effective and easy-to-use way of rapid and specific detection of any type of cells (including pathogens) from suspensions (e.g., body fluids). The possible portability of the device predicts its applicability as a rapid test in clinical diagnostics.

A novel interferometry-based optical sensor to study the coagulation of human plasma

We propose and demonstrate a Twin-interferometry (TIM) based optical approach for studying and exploring anisotropy and directional dependent coagulation kinetics in human plasma under isothermal condition. Human plasma is obtained by centrifuging blood samples collected in Ethylenediamine tetra acetic acid (EDTA) coated vials at 6000 RPM in a laminar flow unit. 0.5 ml of plasma is collected in an optically flat disposable glass cuvette and subjected to induced coagulation by adding equal amounts of CaCl2 solution as coagulant at seven different concentrations. A Twin-interferometer is designed to record the rate of shift in Michelson’s fringes caused by rate of change of optical path difference of coagulating plasma in two orthogonal directions. A pair of interferograms, referred to as the Twin- interferogram (TIG), are recorded for all plasma samples with different CaCl2 concentration during its coagulation. A new approach for extracting various coagulation parameters from TIG, such as anisotropy, half coagulation time, constants governing the rate and dimensionality of coagulation, and their variation along distinct direction is demonstrated. TIG results are validated using polarizing optical microscopic (POM) and optical extinction techniques.

Acoustofluidic Diversity Achieved by Multiple Modes of Acoustic Waves Generated on Piezoelectric-Film-Coated Aluminum Sheets.

Excitation of multiple acoustic wave modes on a single chip is beneficial to implement diversified acoustofluidic functions. Conventional acoustic wave devices made of bulk LiNbO3 substrates generally generate few acoustic wave modes once the crystal-cut and electrode pattern are defined, limiting the realization of acoustofluidic diversity. In this paper, we demonstrated diversity of acoustofluidic behaviors using multiple modes of acoustic waves generated on piezoelectric-thin-film-coated aluminum sheets. Multiple acoustic wave modes were excited by varying the ratios between IDT pitch/wavelength and substrate thickness. Through systematic investigation of fluidic actuation behaviors and performances using these acoustic wave modes, we demonstrated fluidic actuation diversities using various acoustic wave modes and showed that the Rayleigh mode, pseudo-Rayleigh mode, and A0 mode of Lamb wave generally have better fluidic actuation performance than those of Sezawa mode and higher-order modes of Lamb wave, providing guidance for high-performance acoustofluidic actuation platform design. Additionally, we demonstrated diversified particle patterning functions, either on two sides of acoustic wave device or on a glass sheet by coupling acoustic waves into the glass using the gel. The pattern formation mechanisms were investigated through finite element simulations of acoustic pressure fields under different experimental configurations.

Large-Area Film Thickness Identification of Transparent Glass by Hyperspectral Imaging.

This study introduces a novel method for detecting and measuring transparent glass sheets using hyperspectral imaging (HSI). The main goal of this study is to create a conversion technique that can accurately display spectral information from collected images, particularly in the visible light spectrum (VIS) and near-infrared (NIR) areas. This technique enables the capture of relevant spectral data when used with images provided by industrial cameras. The next step in this investigation is using principal component analysis to examine the obtained hyperspectral images derived from different treated glass samples. This analytical procedure standardizes the magnitude of light wavelengths that are inherent in the HSI images. The simulated spectral profiles are obtained using the generalized inverse matrix technique on the normalized HSI images. These profiles are then matched with spectroscopic data obtained from microscopic imaging, resulting in the observation of distinct dispersion patterns. The novel use of images coloring methods effectively displays the thickness of the glass processing sheet in a visually noticeable way. Based on empirical research, changes in the thickness of the glass coating in the NIR-HSI range cause significant changes in the transmission of infrared light at different wavelengths within the NIR spectrum. This phenomenon serves as the foundation for the study of film thickness. The root mean square error inside the NIR area is impressively low, calculated to be just 0.02. This highlights the high level of accuracy achieved by the technique stated above. Potential areas of investigation that arise from this study are incorporating the proposed approach into the design of a real-time, wide-scale automated optical inspection system.

Removal of fiber post under the guidance of digital guide plate and one-piece glass fiber posts-and-cores repair: a clinical report.

This study explores the potential application of computer aided design (CAD)/computer aided manufac-turing (CAM) for one-piece glass fiber posts and cores in restoring tooth defects post-removal of a broken fiber post using a digital guide plate. This paper reports a fractured left upper incisor fiber post removed using a customized needle and digital guide plate. Following root canal retreatment, CAD/CAM integrated fiber post-core and zirconia full crown restoration were completed. The occlusion testing was conducted using the T-Scan Ⅲ system. This study offers insights for managing secondary repair after fiber post fractures.

Preparation and characterization of chitosan and hydroxyapatite composite

Chitosan and hydroxyapatite (HAp) composites were prepared at different ratios (60% chitosan & 40% HAp, 50% chitosan & 50% HAp, 40% chitosan & 60% HAp). The mixtures are dissolved in a 2% acetic acid solution and heated to about 60°C-70°C with continuous stirring for about 1 hour. After that, the solutions are naturally dried on heat-sealing paper placed above a glass sheet. After about 24 hours, chitosan and hydroxyapatite composite films are prepared. Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that Hydroxyapatite is mainly found at lower wave numbers in the range 400–600 cm-1. X-ray diffraction patterns were showed, the crystalline properties of the composites increase with Hydroxyapatite. Differential Thermal Gravimetry (DTG) analysis of the composites indicated that the material is thermally stable up to 300°C. This paper aims to review the literature concerning chitosan-hydroxyapatite composites for bone restoration and discuss the primary methods of preparation and mechanical properties of these materials.