Types Of Crystals Research Articles

Glows to Breakdown Characteristic of ZnO Crystal Growth Using Electric Current Heating Method

Zinc oxide (ZnO) crystals form are various applications could be created like in manufacturing ultraviolet laser and photodetectors. Zinc oxide (ZnO) crystals are synthesized by applying electric current on ZnO ceramic bar which are made using powder metallurgy method. By using Scanning Electron Microscope (SEM) and X-Ray Diffractometer (XRD) could be characterized of ZnO sintered bars easily. The different types of crystal are produced such as polygonal, broken stick, flowers, trunks and many more when applied the DC heating until the sample of ZnO will be glows and breaks apart. The loads or pressure and heating method to the sample of ZnO will be affected to the types of crystal growth. The optimum load is 3 metric tonne and will ease the ignition during DC heating due to less porosity of the samples.

Determination of the process effect on cocoa butter crystallization by rheometer: Kinetic modeling by Gompertz equation.

In this study, the effects of temperature (22, 24, 26, 28, and 30°C) and strain (0.1%, 1%, and 5%) on cocoa butter (CB) crystallization were investigated by oscillatory test, and the four-parameter Gompertz model was used to interpret the effect of parameters on pre-crystallization, nucleation, and crystal growth stages of CB. Lag time and growth rate were calculated using the Gompertz model using time-dependent storage modulus (G') data. According to the results, CB crystallization at 26°C with a 1% strain value had the highest growth rate value, the shortest lag time, and the formation of βv polymorph type. Followingly, polymorphic types of the CB crystals were determined based on the melting points of polymorphs via the temperature ramp step, and the results obtained were correlated with a polarized light microscope. In conclusion, using a rheometer in both the observation of the pre-crystallization process and the determination of polymorph types is very important for research and development studies in the chocolate industry for process and formulation optimization. PRACTICAL APPLICATION: This study demonstrates the feasibility of a novel approach for investigating crystallization and oscillatory shear of CB using a rheometer, both for observing crystallization kinetics and determining polymorph type, accompanied by the Gompertz equation to model the crystallization kinetics. According to the results, the effect of process parameters (temperature and shear) on the crystallization behavior of CB can be observed by rheometer, which can provide a detailed perspective for chocolate manufacturers and researchers in research and development studies.

Machine learning classification methods for battery cathode material crystal system

The optimization of lithium-ion battery material design is becoming increasingly pivotal in the context of the transition to new energy sources. This research delves into the classification of the crystal structures of 339 sets of lithium silicate cathode materials, depending on the chemical and physical parameters of the materials to classify the crystal system type. Five classification algorithms were employed in this study, and the classification accuracy was enhanced through algorithm optimization. Notably, the accuracy of the random forest model with PCA (Principal component analysis) =5 reached 74% accuracy with 80% of the data used for training. Simultaneously, this study optimized the model accuracy by fine-tuning parameters such as depth, k-fold, and learning rate. Through this research, the classification accuracy of cathode materials in batteries was further elevated, bearing significant implications for the development of new, suitable battery materials. This research aids in expediting the screening process for researchers and facilitating industrial-scale experimentation, thereby accelerating the application of next-generation batteries.

The Emergence of the Hexagonal Lattice in Two-Dimensional Wigner Fragments.

At very low density, the electrons in a uniform electron gas spontaneously break symmetry and form a crystalline lattice called a Wigner crystal. But which type of crystal will the electrons form? We report a numerical study of the density profiles of fragments of Wigner crystals from first principles. To simulate Wigner fragments, we use Clifford periodic boundary conditions and a renormalized distance in the Coulomb potential. Moreover, we show that high-spin restricted open-shell Hartree-Fock theory becomes exact in the low-density limit. We are thus able to accurately capture the localization in two-dimensional Wigner fragments with many electrons. No assumptions about the positions where the electrons will localize are made. The density profiles we obtain emerge naturally when we minimize the total energy of the system. We clearly observe the emergence of the hexagonal crystal structure, which has been predicted to be the ground-state structure of the two-dimensional Wigner crystal.

Enhanced Red Emission of Na5Lu9F32: Eu3+ Single Crystal by Introducing of GdF3

AbstractThe bulk Na5Lu9F32 single crystals with high quality serial Eu3+/Gd3+ co‐doped were grown by an ameliorative Bridgman technique. The measurement of X‐ray diffraction (XRD) and analysis of Rietveld refinement were implemented to validate the crystal phase. The Eu3+ doped Na5Lu9F32 single crystal emits intense red emission at 611 nm excited by 394 nm light. The intensity of 1.8 mol % Gd3+ doped sample is boosted by 3.56 times compared with the un‐doped one. The doping of Gd3+ ions replace competitively Lu3+ lattice sites with Eu3+ ions. Thus, they cause the lattice distortion and reduction of symmetry, enabling Eu3+ ions to overcome their 4f forbidden transitions. The change of Eu3+ ion local environment induced by Gd3+ ion doping was explored by the Eu3+ emission spectra and the variations of ratios between red and orange emission intensities (R/O). The fluorescence lifetime indicates that the introduction of GdF3 decreases the probability of non‐radiative transitions and increases the fluorescence lifetime. These results demonstrated that the Na5Lu9F32: Eu3+ single crystal doped with an appropriate concentration of GdF3 is a type of promising red emission single crystal for related optical devices of detector and laser due to its strong red emission, high transparency and high physico‐chemical stability.

Exploration of detection methods for free silica with different crystal forms in dust

Objective: To investigate the differences and applicability of free silica detection methods of different crystal forms in dust, and to provide a basis for the selection of various methods. Methods: From December 2021 to June 2022, dust samples from 20 enterprises in different industries in 18 cities in Henan Province were randomly selected as the investigation objects. X-ray diffraction (XRD) method was used to analyze the samples and classify the samples. Based on GBZ/T 192.4-2007 "Determination of Dust in the Air of Workplace-Part 4: Content of Free Silica in Dust", pyrophosphate method and infrared spectrophotometry were used for quantitative determination. The measured results were analyzed by paired sample t test to evaluate the advantages and disadvantages of the two methods and their applicable scope. Results: The XRD results of 20 dust samples could be divided into α, β, γ crystal types and the mixed type of α and γ. There was no significant difference between pyrophosphate method and infrared spectrophotometry (P=0.180). The pyrophosphate method results of β, γ and α, γ mixed crystalline free silica were significantly higher than those of infrared spectrophotometry, and the difference was statistically significant (P<0.001) . Conclusion: Pyrophosphate method and infrared spectrophotometry are suitable for α-type free silica, while pyrophosphate method is suitable for β, γ and α, γ mixed crystalline free silica.

Crystal scatter effects in a large-area dual-panel Positron Emission Mammography system.

Positron Emission Mammography (PEM) is a valuable molecular imaging technique for breast studies using pharmaceuticals labeled with positron emitters and dual-panel detectors. PEM scanners normally use large scintillation crystals coupled to sensitive photodetectors. Multiple interactions of the 511 keV annihilation photons in the crystals can result in event mispositioning leading to a negative impact in radiopharmaceutical uptake quantification. In this work, we report the study of crystal scatter effects of a large-area dual-panel PEM system designed with either monolithic or pixelated lutetium yttrium orthosilicate (LYSO) crystals using the Monte Carlo simulation platform GATE. The results show that only a relatively small fraction of coincidences (~20%) arise from events where both coincidence photons undergo single interactions (mostly through photoelectric absorption) in the crystals. Most of the coincidences are events where at least one of the annihilation photons undergoes a chain of Compton scatterings: approximately 79% end up in photoelectric absorption while the rest (<1%) escape the detector. Mean positioning errors, calculated as the distance between first hit and energy weighted (assigned) positions of interaction, were 1.70 mm and 1.92 mm for the monolithic and pixelated crystals, respectively. Reconstructed spatial resolution quantification with a miniDerenzo phantom and a list mode iterative reconstruction algorithm shows that, for both crystal types, 2 mm diameter hot rods were resolved, indicating a relatively small effect in spatial resolution. A drastic reduction in peak-to-valley ratios for the same hot-rod diameters was observed, up to a factor of 14 for the monolithic crystals and 7.5 for the pixelated ones.

Comparative Study of the Performances of Octenyl Succinic Anhydride‐Modified Agriophyllum squarrosum and Quinoa Starches to Stabilize Pickering Emulsions

AbstractVery small granule starch is a good source for effective Pickering emulsion stabilizers. In this study, native Agriophyllum squarrosum (A. squarrosum) starch (N‐AS) and native quinoa starch (N‐QS) are modified by octenyl succinic anhydride (OSA), and the physicochemical as well as the emulsifying characteristics of two modified starches are evaluated. Fourier transform infrared spectroscopy (FTIR) shows that the esterification reactions between OSA and the two starches are successful, and the substitution effect of OSA‐modified A. squarrosum starch (OSA‐AS) is better than that of OSA‐modified quinoa starch (OSA‐QS). X‐ray diffraction (XRD) analysis shows that OSA modification does not alter the crystal type of the starch particles. OSA modification increases the particle size and hydrophobicity of both starches, and the particles of OSA‐AS are smaller than that of OSA‐QS, which corresponded to the fact that N‐AS possesses a smaller particle size compared to native N‐QS. OSA‐modified starches are arranged at the interface of oil–water to stabilize the emulsion. The OSA‐AS displays better performance of stabilizing emulsion than OSA‐QS. The Pickering emulsions formed by all OSA‐modified starch samples are mainly elastic gel‐like emulsions. In summary, OSA‐AS is more suitable for Pickering emulsion stabilizer than OSA‐QS.

Preparation of CaWO4-based glass-ceramics with uniform crystal distribution and enhanced luminous property by thermoelectric coupling treatment

To address the issue of crystal aggregation in CaWO4-based glass-ceramics under high temperature or prolonged durations, while also aiming to enhance the luminescent properties, a thermoelectric coupling treatment is introduced during the preparation process of glass-ceramics. In this study, the influence of applying an external DC electric field on the nucleation and crystallization was examined. Techniques such as DSC, XRD, and SEM are utilized to investigate the crystal types and microstructure of the glass-ceramics. Furthermore, the luminescent performance under ultraviolet and X-ray is characterized, with PL, PLE, and XEL spectra being measured. The findings reveal that thermoelectric coupling treatment augments the crystallization content, refines crystal distribution, and enhances luminescent properties. The applied DC electric field provides energy for thermodynamic reactions, reduces activation energy for bond breaking, accelerates ion migration, and facilitates crystal nucleation precipitation. Crucially, it induces polarization of Ti and Zr ions within crystal nuclei, generating electrostatic repulsion between nuclei. These effects mitigate crystal aggregation, refine distribution, and amplify crystal count. This underscores the potential of thermoelectric coupling treatment in synthesizing optical materials utilizing glass-ceramics as luminescent base materials, offering insights for similar researches endeavors.

Kristjánite, KNa2H(SO4)2, a new fumarolic mineral from Iceland containing the [SO4–H–SO4]3– anion in the crystal structure

Abstract Kristjánite, KNa2H(SO4)2, is a new mineral (IMA2022–131) found in a high-temperature fumarole on Fimmvörðuháls, Iceland. It is monoclinic, P21/n, a = 6.9625(1), b = 9.9953(1), c = 11.0928(2) (Å), β = 105.637(2)° and V = 743.40(2) Å3. Kristjánite forms colourless transparent crystals up to ~100 μm in size in compact aggregates with metathénardite, belomarinaite, aphthitalite, ivsite and an unknown mineral with tentative composition K2NaH(SO4)2, or grows in white globules of smaller grains on their surface. The eight strongest maxima in a powder X-ray diffraction diagram are [d, Å (Intensity)] 4.37 (59), 3.65 (32), 3.48 (78), 3.36 (100), 3.18 (76), 2.83 (43), 2.73 (38) and 2.405 (23). The mineral represents a novel crystal structure type. In it, K is coordinated by eight O atoms, and two symmetrically independent Na atoms by seven O atoms. Two symmetrically independent S atoms are in tetrahedral coordination by O atoms. A close to linear, very short hydrogen bond (2.44 Å), connects the two to a SO4–H–SO4 dimer. K and Na coordination polyhedra share vertices, edges and even faces forming with sulfate tetrahedra a tight structure with narrow [100] channels lined on two opposite sides by hydrogen bonds.

Nano‐Calcium Carbonate with Core–Shell Structure was Prepared by Dopamine Chelation Using Pluronic F‐127 as Template

AbstractHerein, a new template carbonization method is used to prepare calcite‐type nano‐calcium carbonate (CaCO3) with a core–shell structure using calcium hydroxide as a solute and Pluronic F‐127 as a templating and pore‐forming agent. Dopamine hydrochloride is added to control the size of calcium hydroxide particles. The morphology, particle size, and crystal type of CaCO3 are characterized via transmission electron microscopy, X‐ray diffraction, nanoparticle size, and zeta potentiometer. The creation of core–shell calcium carbonate nanoparticles is examined in relation to reaction circumstances (i.e., additive sequence, additive amount, and additive mixing time), carbonization temperature, liquid flow rate, and templates with varying chain lengths. Furthermore, a discussion is held regarding the formation mechanism of spherical core–shell calcium carbonate that is created using the innovative template carbonization method. The results show that the order, amount, liquid flow rate, and template type of additives have a significant effect on the crystal shape of calcium carbonate nanoparticles. The mixing time of additives has a significant effect on the particle size of calcium carbonate nanoparticles. Interestingly, the thickness of the shell depends on the carbonization temperature, and too slow or too fast flow rate will lead to the formation of cyclic calcium carbonate nanoparticles.

Effect of a 10-Methacryloyloxydecyl Dihydrogen Phosphate-treated Bioceramic Sealer on the Bond Strength of an Endodontic Fiber Post: Multilayer Composite Disk Models and Ultra-highspeed Imaging Analysis.

Multiple materials are found in the root canal after fiber-post cementation. The layer of a bioceramic-based (BC) sealer may affect the bond strength (σBS) of the fiber post in the root canal. The purpose of this study was to employ multilayer composite-disk models in diametral compression to investigate whether the bond strength between a fiber post and root dentin can be increased by the application of a primer on the BC sealer. The multilayers of materials in the root canal required 3D finite-element (FE) stress analyses (FEA) to provide precise σBS values. First, BC sealer was characterized using x-ray powder diffraction (XRD) to determine when the sealer completely set and the types of crystals formed to select which primer to apply to the sealer. We selected a 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP)-based primer to treat the BC sealer before post cementation. Ultra-highspeed (UHS) imaging was utilized to analyze the crack initiation interface. The obtained failure force was used in FE analysis to calculate σBS. UHS imaging validated the fracture interface at the post-dentin junction as FEA simulations predicted. σBS values of the fiber posts placed with various material combinations in the root canal were 21.1 ± 3.4 (only cement/ post), 22.2 ± 3.4 (BC sealer/cement/post) and 28.6 ± 4.3 MPa (10-MDP primer treated BC sealer/cement/post). The 10-MDP-treated BC sealer exhibited the highest σBS (p < 0.05). The multilayer composite disk model proved reliable with diametral compression testing. The presence of BC sealer in the root canal does not reduce σBS of the fiber post. Conditioning the BC sealer layer with 10-MDP primer before fiber-post cemen-tation increases σBS.

Insight into the structure and crystallization of SiO2-Al2O3-P2O5-Na2O-MgO-CaO glass system with Mg-Ca substitution: A molecular dynamics study

Transparent glass ceramics (TGCs) have shown great prospects in many application fields. Understanding the effect of oxides on glass network structure and crystallization is essential for designing TGCs. A series of 18Na2O-(16-x)CaO-xMgO-3P2O5-2.5Al2O3-60.5SiO2 (mol%, x = 0, 4, 8, 12, 16) glass-ceramics were studied with Molecular dynamics (MD) simulations, and the effect of CaO substituted by MgO on the glass structure and crystallization was analyzed in details. The results show that MgO statistically behaves as a network former, and the overall network connectivity increases with the substitution of MgO for CaO. Further structure analysis shows that the complex glass system consists of Si-rich and P-rich phases, which respectively contain Si-Mg-rich regions with 2Mg1Si-related tricluster oxygens (TBOs) and P-Mg-rich regions. The energetically unfavorable TBOs and Mg4-O-Mg4 linkages provide favorable nucleation sites for homogeneous nucleation, and the so-called ‘Coordination matching’ principles are proposed to explain the type of crystals. These results help us understand the crystallization of Mg-containing glass ceramics and benefit the future design of novel spontaneous TGCs.

Preparation and properties of polyvinylidene fluoride dielectric nanocomposites for energy storage applications through synergistic addition of ionic liquid‐modified graphene oxide nanosheets and functionalized barium titanate hybrid fillers

AbstractTo tackle the challenge of filler agglomeration and low interfacial bonding strength during manufacturing filled polymer dielectric nanocomposites containing graphene oxide (GO) nanosheets, the author proposed an interface design strategy based on the synergistic hybridization of ionic liquid (IL) modification and different dimensional fillers. GO nanosheets were functionalized by IL, and then polyvinylidene fluoride (PVDF) dielectric nanocomposites (GO‐g‐IL/PVDF) were prepared and evaluated. Based on this, hydroxylated barium titanate BT‐OH@GO‐g‐IL/PVDF ternary nanocomposites were further prepared. A comprehensive analysis of the morphology, mechanical, thermal, electrical, and dielectric properties of the PVDF dielectric nanocomposites was systematically conducted. The results showed that IL was successfully grafted on GO, benefiting an increase in the filler dispersion and interfacial bonding strength. GO‐g‐IL also promoted β‐crystal formation of PVDF and increment of crystallinity. DSC test further revealed that the inclusion of BT‐OH@GO‐g‐IL as dielectric nanofillers promoted the formation of multiple crystal types in PVDF and accelerated the crystallization process. The incorporation of GO‐g‐IL facilitated the formation of localized conductive networks within the PVDF matrix, leading to enhanced electronic displacement polarization and an improved dielectric constant. The dielectric constants of the GO‐g‐IL/PVDF composites containing 2% and 8% of GO‐g‐IL were measured to be 24.28 and 78.46, which were found to be 2.6 and 8.4 times higher than that of pure PVDF. However, the dielectric loss also increased sharply at high nanofiller loading. The dielectric constant and loss of the BT‐OH@GO‐g‐IL/PVDF nanocomposites were found to be 40.32 and 0.38, with a content of 2% for GO‐g‐IL and 20% for BT‐OH.Highlights A facile interface design strategy based on ionic liquid (IL) integrating GO nanosheets and hydroxylated barium titanate (BT‐OH) to form BT‐OH@GO‐g‐IL compounding nanofiller has been proposed. PVDF dielectric nanocomposites containing BT‐OH@GO‐g‐IL compounding nanofiller were systematically investigated and compared. The effects of interfacial interactions between BT‐OH@GO‐g‐IL and PVDF contribute to the uniform dispersion and comprehensive property improvements of PVDF dielectric nanocomposites. This work provides a novel strategy for the fabrication of PVDF dielectric nanocomposites, inspiring the research and development of PVDF in the energy storage applications areas in the future.

Failure Mechanism and Residual Stress Analysis of Crystal Materials for the Thermal Battery

This paper investigates the thermal battery as a research topic. We conducted an in-depth analysis of various thermal battery aspects, such as the cathode material CoS2 and electrolyte material morphology, crystal type, and interface state changes before and after service. The aim was to explore the core reaction and main failure mechanisms of the thermal battery. Prior to the reaction, the thermal battery cathode and electrolyte material consisted of pure-phase CoS2 and a composition of MgO-LiF/LiBr/LiCl. After service, the cathode and electrolyte of the single thermal battery exhibited significant morphological alterations caused by the presence of a molten state. The cathode transformed from CoS2 to Co3S4 and Co9S8 together with the presence of a marginal quantity of Co monomers visible throughout the discharge process, which was confirmed by means of XRD and XPS analyses. After the reaction, the electrolyte material was primarily made up of LiF, LiBr, and LiCl while the crystal components remained largely unaltered, albeit with apparent morphological variations. As was deduced from the thermodynamic analysis, the cathode material’s decomposition temperature stood at 655 °C, exceeding the working temperature of the thermal battery (500 °C) by a considerable margin, which is indicative of outstanding thermal durability within the thermal battery’s operational temperature range. Furthermore, the discharge reaction of the positive electrode was incomplete, resulting in reduced CoS2 residue in the thermal battery monomer after service. The reaction yielded a combination of Co3S4, Co9S8, and small amounts of Co monomers, indicating possible inconsistencies in the phase composition of the pole piece during the reaction process. In this study, we examine the distribution of residual stress in the thermal battery under various operating conditions. The simulation results indicate that exposure to a 70 °C environment for 2 h causes the maximum residual stress of the battery, which had an initial temperature of 25 °C, to reach 0.26 GPa. The thermal battery subjected to an initial temperature of 25 °C exhibited a maximum residual stress of 0.42 GPa subsequent to a 2-hour exposure to a temperature of −50 °C.

Enhancing fluorescence properties in transparent glass ceramics via optimized Gd2O3/Ga2O3 ratios and crystallization conditions

In this study, Gd2O3–Ga2O3-GeO2-Nd2O3 glasses and glass ceramics were synthesized, and their structural, thermal, and crystallization characteristics were analyzed. Our findings indicate that substituting Gd2O3 for Ga2O3 positively influences the enhancement of bridge oxygen content and network structure stability. Heat treatments at different temperatures showed no significant impact on the crystal phase type but did alter the crystallization rate. Optimal conditions were identified: a Gd2O3/Ga2O3 ratio of 0.6 facilitated the production of transparent glass ceramics containing a single-phase GdGaGe2O7 nano-crystal. Notably, the glass ceramic nucleated at 780 °C for 24 h and crystallized at 840 °C for 5 min exhibited superior performance. Despite a 6% reduction in transmission rate, the emission intensity at 1060 nm increased by 1.5 times. This material holds promise for various applications in solid-state lasers operating within the 1.06 μm region.

Preparation of Silicon Carbide Powder from Amorphous Silica and Investigation of Synthesis Mechanism

An innovative process for preparing silicon carbide (SiC) from acid leaching residue of ferronickel slag through a carbon–thermal reduction process was proposed in this study. The results indicate that the acid leaching residue is an ideal silicon source for SiC preparation according to its high amorphous silica content of 84.20% and fine particle size of d50 = 29.16 μm. Compared with carbon black, activated carbon, and graphite, coke is the more appropriate carbon source for SiC preparation. A micron-size SiC powder with grade of 88.90% and an average particle size (d50) of 44.68 μm can be obtained under the following conditions: the mass ratio of coke to leaching residue as 1.2:1, in an air atmosphere, reducing at 1600 °C for 3 h, following by decarbonizing at 700 °C for 4 h. The XRD, SEM and FTIR analyses show that the prepared powder is 3C-SiC and belongs to the β-SiC crystal type. Based on thermodynamic analysis and micromorphology observation, it can be concluded that with amorphous silica as the silicon source, the carbon–thermal synthesis of SiC powder follows both the solid–solid reaction mechanism and the gas–solid mechanism. The SiC created through solid–solid reaction is primarily nucleated in situ on amorphous SiO2, with a size close to that of the original acid-leaching slag, while the SiC generated according to the gas–solid mechanism mainly nucleates heterogeneously on the surface of carbon particles, resulting in a smaller particle size and mostly adhering to the surface of solid–solid nucleated SiC particles. This study provides a feasible method for the effective utilization of amorphous silica, which is also significant for the efficient consumption of the vast acid leaching residue.

Alterations in magnetic properties of crystals of trinuclear copper complexes: isolated entities versus one-dimensional chains

Abstract We obtained two types of crystals of a complex under different crystallization conditions, each exhibiting distinct molecular arrangements and magnetic interactions: one type consists of isolated complexes, while the other forms one-dimensional chains without extra bridging ligands. This approach provides a new avenue for tuning the magnetic properties of metal-complex-based materials.

A new ex vivo human model of osteoarthritis cartilage calcification.

Cartilage pathologic calcification is a hallmark of osteoarthritis (OA). Here, we aimed to describe a new ex vivo human model to study the progression of cartilage calcification. Cartilage explants (n = 11), as well as primary chondrocytes (n = 3), were obtained from OA patients undergoing knee replacement. Explants and chondrocytes were cultured in control (NT) or calcification (CM) medium (supplemented with ascorbic acid and β-glycerophosphate). Calcification was evaluated by micro-CT scan at day 0 and 21 in explants, and by Alizarin red staining in chondrocyte monolayers. Raman spectrometry allowed characterization of the crystal type. Interleukin-6 (IL-6) secretion in explant and cell supernatants was measured by ELISA. Finally, matrix degradation was evaluated by Safranin-O staining of explant sections and by glycosaminoglycans (GAG) release in supernatants. Micro-CT scan showed calcifications in all explants at baseline (day 0), which in the CM group increased significantly in number and size after 21 days compared with the NT group. Raman spectrometry revealed that crystals were exclusively basic calcium phosphate crystals (carbonated hydroxyapatite) both in NT and CM. IL-6 secretion was significantly increased in calcifying conditions. Finally, CM significantly increased cartilage catabolism as assessed by decreased Safranin-O staining of tissue explants and increased GAG release in supernatants. CM effects (enhanced calcification, IL-6 secretion and proteoglycans turn-over) were recapitulated in vitro in OA chondrocytes. We have described a new ex vivo human model of cartilage calcification that can summurize the triad of events seen during osteoarthritis progression, i.e. calcification, inflammation, and cartilage degradation. This model will allow the identification of new anti-calcification compounds.

Effect of angle of incidence on defect modes of symmetric and asymmetric one-dimensional photonic crystals

The impact of the angle of incidence on defect modes within a one-dimensional photonic crystal (PC) containing a central defect has been thoroughly examined. We have considered two distinct types of photonic crystals, each featuring a solitary defect: symmetric PCs and asymmetric PCs. Our findings reveal that in the case of asymmetric PCs, a defect mode emerges precisely at the central wavelength. Conversely, for symmetric PCs, two distinct defect modes appear in the proximity of the central wavelength. By widening the defect layer, these two defect modes can be merged into a single central defect mode. However, it's worth noting that the intensities of these merged defect modes differ from those observed in the asymmetric case. We have analyzed the propagation characteristics of the proposed structure using the transfer matrix method.