Formation Mechanism Of Crystals Research Articles

Research Progress on the Effect and Mechanism of Superchilling Preservation Technology on Meat Quality Control.

During storage and transportation, meat is susceptible to the effects of microorganisms, endogenous enzymes, and oxygen, leading to issues such as moisture loss, spoilage, and deterioration. Superchilling, as a preservation method that combines the benefits of refrigeration and freezing, can effectively slow the growth and reproduction of microorganisms, control protein and lipid oxidation, reduce water loss, and maintain the quality and sensory properties of meat. This paper reviews the current application status of superchilling technology in meat preservation, focusing on the mechanisms of ice crystal formation, water retention, tenderness preservation, protein and fat oxidation control, and microbial growth inhibition under superchilling conditions. Additionally, it summarizes the research progress on the combined application of superchilling with emerging technologies such as electric fields, magnetic fields, and electron beams in meat preservation and explores its potential and future prospects for improving meat quality. The aim is to provide scientific evidence and technical support for the application of superchilling technology in enhancing meat quality.

Palaeobiological and geochemical aspects of reptilian coprolites from a Maastrichtian Deccan volcano-sedimentary intertrappean deposit of central India

Cretaceous-Paleogene coprolite (fossilized faecal matter) records are significant in terms of providing direct palaeobiological evidence (from inclusions) in order to understand the diet of producer animal(s). In the past >150 years, research investigations (in India) have focussed on the Maastrichtian Type-A coprolite morphotype. Consequently, little information is available on the overall assemblage of Indian Maastrichtian vertebrate coprolites in terms of their morphological diversity, chemical composition, biotic-abiotic inclusions in the context of producer linkage(s) and geographic distribution within the Deccan volcano-sedimentary infra- and intertrappean deposits of India. Therefore, we present a detailed record of a coprolite assemblage from the Maastrichtian intertrappean deposits of Lotkheri, central India. This coprolite assemblage comprises five morphotypes based on their geometry, surface, and internal textures. Morphological considerations and biotic inclusions suggest that reptiles were the most likely producers of these ichnofossils. The associated faunal remains of reptiles (mainly chelonians and crocodilians) support this hypothesis. Dentalites or bite traces of Garfish (genus Lepisosteus) observed on the external surface of a few coprolite specimens (studied herein) are a rarity in the global fossil records. The analytical evidence confirm the phosphatic composition of the coprolites with the unique presence of three distinct morphologies (i.e. spherical, rods, and needles) of apatite crystals. Finally, we provide the chemical nature and plausible mechanism of apatite crystal formation via the chemical processes undergoing during the biomineralization of these crystals observed within coprolites.

Use of magnetic fields to impact glass-transition and crystallization during manufacturing of ZBLAN optical fibers

ZBLAN (ZrF4-BaF2-LaF3-AlF3-NaF) is the most stable glass among the Heavy Metal Fluoride (HMF) family and has a wide range of applications in medical industry, telecommunication, IR transmission, among others. But, due to crystal formation while manufacturing of ZBLAN fiber its theoretical minimum loss has not been achieved yet. Some techniques such as high cooling rate and microgravity conditions have been utilized to reduce the crystal formation but are challenging to implement during manufacturing of these fibers. Alternatively, magnetic field (MF), also a body force like gravity, is expected to influence the crystal formation mechanism and glass kinetics. In this work, ZBLAN glass is processed under magnetic fields of various intensities while simulating fiber drawing manufacturing process conditions. Then, the processed ZBLAN is analyzed using Differential Scanning Calorimetry (DSC) at varying scanning rates. Various glass kinetics parameters such as activation energy, fragility, and preferred crystallization mechanism in terms of Avrami parameter (n) have been analyzed. The glass transition temperature (Tg) increases for a given sample as scanning rate (β) increases. Samples processed under varying magnetic fields, at the same scanning rate, displayed higher glass transition temperatures. Also, when the magnetic field increases, the activation energy required for glass transition decreases, and the fragility index (m) decreases. There is also a preference for surface crystallization over volume crystallization. These results encourage application of magnetic fields for reducing crystal formation while processing ZBLAN glass.

Basic Theory of Ice Crystallization Based on Water Molecular Structure and Ice Structure.

Freezing storage is the most common method of food preservation and the formation of ice crystals during freezing has an important impact on food quality. The water molecular structure, mechanism of ice crystal formation, and ice crystal structure are elaborated in the present review. Meanwhile the methods of ice crystal characterization are outlined. It is concluded that the distribution of the water molecule cluster structure during the crystallization process directly affects the formed ice crystals' structure, but the intrinsic relationship needs to be further investigated. The morphology and distribution of ice crystals can be observed by experimental methods while simulation methods provide the possibility to study the molecular structure changes in water and ice crystals. It is hoped that this review will provide more information about ice crystallization and promote the control of ice crystals in frozen foods.

Single-point substitution F97M leads to in cellulo crystallization of the biphotochromic protein moxSAASoti

To enhance the photoconversion performance of biphotochromic moxSAASoti protein, a substitution F97 M was introduced. In addition to enhancing the target properties, this substitution also resulted in the crystallization of the recombinant protein within living HeLa cells (also referred to as in cellulo crystallization). The phenomenon of protein crystallization in living cells is not unique, yet the mechanisms and application of in cellulo crystallization remain significant for further research. However, in cellulo crystallization is atypical for fluorescent proteins and detrimental for their biotechnological application. The objective of this study was to elucidate the underlying mechanisms responsible for the crystallization of moxSAASotiF97Min cellulo. For this purpose, the crystal structure of the green form of biphotochromic protein moxSAASotiF97M was determined at high resolution, which surprisingly has a space group, different from those of parent mSAASotiC21N. The analysis provided allowed to propose a mechanism of new crystal contacts formation, which might be a cause of in cellulo protein crystallization.

Impurity formation mechanism of silicon carbide crystals smelted by Acheson process

Impurity formation mechanism of silicon carbide crystals smelted by Acheson process

Study on the mechanism of second phase formation in high-purity fused silica materials for semiconductor application

Gas bubble is a common defect in high-purity fused silica materials, but the formation of the second phase particles related to gas bubble and its mechanism remain unclear till now. In this work, we have presented a method for characterization of colored gas bubbles in high-purity fused silica crucibles for Czochralski silicon by the means of TEM and EDX. Based on it, the origin of the coloring of the gas bubbles is demonstrated to be induced by the gathering of Fe impurity and then, the formation of high-density second phase—ferric oxide (Fe2O3) crystals around the gas bubbles. Moreover, our results provide insight into the formation mechanism of second phase crystals which can be induced by stress field variations around gas bubbles during the cooling process that probably promoted by volume shrinkage effect and increasing solubility of gas from gas bubbles into fused silica substrate. The understanding of the second phase particle formation mechanism in high-purity fused silica materials is valuable for its further controlling.

(H3O)Li2(IO3)3: crystal structure and IR spectrum

The synthesis, IR spectroscopy, thermal and UV-Vis transmittance of the new lithium iodate crystal: (H3O)Li2(IO3)3, were studied. The crystal structure of (H3O)+·2(Li)+· 3(IO3)- was determined by single-crystal X-Ray diffraction analysis at 100(2) K. It crystallizes in the monoclinic system (P21/n) with the parameters: a = 8.3266(12) Å, b = 10.9893(17) Å, c = 11.2472(17) Å, α = γ = 90°, β = 111.360(4)° and Z(Z') = 4(1). The structure contains a hydronium cation (H3O)+, three crystallographic independent trigonal pyramidal IO3 anions, and two independent cations (Li)+ coordinated each by four oxygen atoms 3(IO3)- at the apices of strongly deformed tetrahedrons. The research results have revealed the mechanisms of crystal formation and the characteristic absorption bands of functional groups, which are of scientific importance. The possibility of the existence of certain properties is also discussed.

Pressure Shift Freezing: An Alternate Method of Freezing for Meat and Marine Products and Their Quality Characteristics

The comprehensive demand for meat and seafood in the global market has raised a severe need for processing and preservation strategies to conserve their inherent quality. It is widely perceived that the present conventional meat production system engages freezing as the primary preservation technique, and reports have documented several challenges associated with existing freezing approaches, like the creation of ice crystals during phase transition, which causes deterioration of the tissue membrane, destruction of the cell wall, and textural damage to the foods. Thus, interest in alternative food freezing methodologies, such as pressure shift freezing (PSF), has emerged as a matter of immense approaches and commercial interest owing to its massive benefits. This review delivers the fundamentals of PSF, including the mechanisms of ice crystal formation and microbial inactivation. Further, this review briefly states the applications of PSF in meat processing and preservation by compiling recent works. This provides insight into emerging trends and research requirements. High‐pressure freezing creates rapid and homogenous ice crystal development all over the food sample. Moreover, the impact of pressure on the quality aspect of PSF‐treated food was discussed. Also, the changes in functional characteristics of PSF‐treated foods like colour, texture, and WHC have been highlighted. Finally, aspects that can be further notably analysed, the obstruction that confines the implementation of this innovation on a large scale, and opportunities have been presented.

High temperature Raman spectroscopic analysis of the crystal growth of Bi2ZnOB2O6

Micromechanism of crystal growth has received considerable attention as a fundamental subject. However, in situ observation of the crystal growth process remains challenging. In this study, high-temperature Raman spectroscopy has been utilized to investigate the growth pattern of Bi2ZnOB2O6 crystals via in situ exploration of the starting solution structure near the crystal–solution interface. The experimental results show that the solution primarily consists of ZO4 and BO3 units corresponding to 370, 539, 664, and 1293 cm−1 vibration frequencies. These units connect with each other forming longer chains in the area close to the crystal, and they are related to the presence of low-wavenumber vibrations in the Raman spectrum. Furthermore, a loose embryonic structure of the Bi2ZnOB2O6 crystal is observed near the crystal–solution interface owing to the formation of Bi–O bonds. Therefore, this study successfully provides a clear understanding of the formation mechanism of Bi2ZnOB2O6 crystals.

Preparation and formation mechanism of colorful photonic crystals on rough yarns

The environmentally friendly dyeing of textiles combining regular photonic crystals (PCs) has shown remarkable promise for application. However, the surface is rough and undulating and contains many harnesses due to full-curved structure of yarns. All these factors increase the difficulty of assembling colloidal microspheres into regular PCs on yarns. Therefore, relevant studies on the preparation methods and fundamental theories for constructing bionic structural colors on conventional flexible yarns are few. This study contains two main parts: first, regular PC-based yarns were produced by the dip coating method with poly (styrene–butyl acrylate–methacrylate) (P(St–BA–MAA)) as building block. Specifically, the softness and surface flatness of acrylic yarns were improved using silicone-modified polymer solution and cationic acrylate solution. The results indicated that assembling of PC with vivid structural color was easier when the base color of yarns was black and the concentration of P(St–BA–MAA) colloidal microspheres was about 60 wt%. Second, the self-assembling mechanism of microspheres on acrylic yarns was further studied by untwisting and slicing. The results showed that colloidal microspheres would fill the surfaces and voids of the outer fibers of acrylic yarns to form regular PCs, and they would also enter the inner fibers of yarns by capillary forces. However, the structure of yarns was tight inside and loose outside due to twisting and other reasons. Therefore, the colloidal microspheres had more difficulty entering the fibers on the inner side of the yarn to form an ordered PC structure when the fibers were closer to the yarn axis. The PC-based colored yarn also remained bright after the rubbing test. The color phase of the structured colored yarns based on PC could be adjusted as well by regulating the particle size and the observation angle. The prepared structured colored yarns were woven into fabrics, which were named yarn-structure colored fabrics. This research provides theoretical support and technical guidance for the preparation and practical application of flexible structured colored yarns based on PC.

Preparation and performance study of sedum multiceps-like biomimetic structure TKX-50 with various particle sizes

Biomimetic structures often endow materials with excellent performance. In order to explore the impact of biomimetic structures on the performance of energetic materials, the sedum multiceps-like bionic structure dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) was constructed by self-assembly technology, and controllable particle size adjustment was achieved. Moreover, the effects of solvent ratio, solute content, stirring flow field, and temperature on the quality of sedum multiceps-like TKX-50 crystals were explored, and the formation mechanism of sedum multiceps-like TKX-50 crystals was analyzed. Then, the crystal morphology, crystal form and particle size distribution of sedum multiceps-like TKX-50 were characterized, furthermore, the thermal properties and mechanical sensitivity of sedum multiceps-like TKX-50 were emphatically studied. The results showed that the sedum multiceps-like biomimetic structure TKX-50 was assembled from needle shaped or sheet shaped small particle crystals, and the sedum multiceps-like structure did not change the explosive crystal form of TKX-50. What's more, the thermal decomposition activation energy of the prepared sedum multiceps-like TKX-50 crystal was at least 157.30 kJ⋅mol−1 and at most 185.27 kJ⋅mol−1, and the thermal energy was greatly affected by particle size. In addition, the minimum and maximum ultimate impact energy of the sedum multiceps-like TKX-50 crystals are 20 J and 55 J. The ultimate impact energy of the sedum multiceps-like TKX-50 crystal with different particle sizes is higher than that of the raw TKX-50 (15 J). As a consequence, the sedum multiceps-like bionic structure effectively improves the energy release of TKX-50, reduces the impact sensitivity, and improves the uniformity of particle size distribution.

Some problem questions in studying the properties of dynamically vulcanized polymer systems based on ethylene/1-hexene copolymer and nitrile butadiene rubber

The article presents the results of a study of the influence of the type and concentration of nitrile butadiene rubber on the main physical and mechanical properties of polymer compositions based on compatibilized ethylene/1-hexene copolymer (EHC*). SKN-18, SKN-26, and SKN-40 were used as nitrile butadiene rubber. The compatibilizer – polyethylene-graft-methacrylic acid was used to improve the compatibility of the mixed components of the mixture. At the first stage, the task of the study was to investigate the effect of the concentration of the considered nitrile rubbers on such properties of the compositions as yield strength, tensile strength, elongation at break, flexural strength, melt flow rate and heat resistance. It was found that, regardless of the type of used nitrile butadiene rubber, with an increase in its content in the composition of the ethylene/1-hexene copolymer, a regular decrease in strength parameters, heat resistance, and melt fluidity is observed. It is shown that with the loading of 30 wt% SKN-18 or 40 wt% SKN-26 and SKN-40 into the composition of the ethylene/1-hexene copolymer phase inversion occurs in the composite materials, according to which the dispersed phase becomes a dispersed medium. The thermomechanical properties of the considered samples were studied. It was found that in those samples in which phase inversion occurred, a region of a highly elastic plateau is formed, which increases with an increase in the content of the rubber component. This area indicates the formation of elastomer with rubber properties. The regularities of crystallization of the compositions depending on the content of the amorphous component were studied by the method of stepwise dilatometry. The mechanism of crystal formation was studied depending on the content of the amorphous component. The influence of the crosslinking agent concentration – dicumyl peroxide on the main properties of dynamically vulcanized elastomers has been studied.

Study on Crystallization Mechanism of Asphalt Mixture in Bridge Deck Pavement

This study focuses on unknown crystal precipitates from an asphalt mixture used in bridge deck pavement layers. X-ray fluorescence spectroscopy was used to analyze the composition and source of crystals in the asphalt mixture used in bridge deck pavement, and infiltration tests, porosity tests, splitting tests and multi-wheel rutting tests were carried out to determine the precipitation area and non-precipitation area to explain the influence of crystals on the road performance of an asphalt pavement. A nuclear-free densitometer and 3D ground-penetrating radar (3D GPR) were used to detect the porosity and thickness uniformity of the whole section to study the formation mechanism of crystals. The results showed that the main components of crystals were water molecules, while the rest mainly came from machine-made sand, and there was no significant difference in pavement performance in the areas where crystals precipitated. The crystals were mainly caused by rainwater penetrating into the pavement through coarse segregation areas and collecting in the depression of the lower bearing layer. Under high temperature, the solution precipitated out of the pavement and formed crystals.

E062 Calcium pyrophosphate dihydrate crystal in operated rheumatoid arthritis of the knee

Abstract Background/Aims Calcium pyrophosphate dihydrate (CPPD) crystals are also one of the common types of crystals causing crystal-induced inflammatory arthritis. Several studies have elucidated important aspects of the molecular and cellular mechanisms of CPPD crystal formation. CPPD crystal deposition disease is a common arthritic disorder in mainly elderly patients. CPPD crystals are found in multiple joints (e.g. knee, wrist joints) in association with severe cartilage degeneration in osteoarthritis. However, there are few reports concerning about CPPD crystals in patients with rheumatoid arthritis (RA). In this study, I investigated the relationship between CPPD crystal and operated RA of the knee. Methods Seventy-seven total knee arthroplasties were performed for RA knees from January 2016 to September 2021. I defined the lower extremity alignment (LEA) base on the femorotibial angle (FTA) as valgus (FTA<170°), neutral (170°≤FTA<180°), and varus (FTA≥180°). I also defined the osteophyte formation degree (OFD) in the knee (grade 0-3). At the operation, joint fluids were collected from 70 knees (average age 71.6; male 8; female 72 body mass index (BMI) 24.4kg/m2,; C-reactive protein (CRP) 1.20mg/dL; erythrocyte sedimentation rate (ESR) 49.5mm/h; matrix metalloprotease (MMP)-3 289.5ng/dL; OFD (0/1/2/3) 0/38/25/7; FTA 177.9°; LEA: varus 35; neutral 22; valgus 13). We evaluated the relationship between CPPD crystals and age, gender, FTA, BMI, CRP, ESR, MMP-3, OFD and LEA. When I analyzed the risk factors using the logistic regression method, LEA were defined as valgus (FTA<175°) and varus (FTA≥176°). Results CPPD crystals were detected from 19 RA knees (27.1%). There were no significant differences between CPPD(+) and (-) groups about age, gender, FTA, BMI, CRP, ESR and MMP-3. The more severe osteophyte formation showed higher CPPD(+) rate tendency; however, there was no significance. CPPD(+) rates were 34.2% in varus knees, 23.1% in valgus knees and 18.2% in neutral knees, respectively. We reported that age, valgus knee, severe osteophyte and low BMI were the risk factors of CPPD(+) in operated osteoarthritis (OA) knees, previously. In this study, there was no difference between CPPD(+) and (-) groups about these factors. Especially, CPPD(+) rate in RA valgus knees was one third of that of OA valgus knees. Conclusion It may be suggested that CPPD production mechanism in RA knees is different from that in OA knees. Disclosure M. Nishikawa: None.

General behavior and mechanisms of dendritic crystal formation in evaporated biological solutions and their significance for solution analysis

By studying the evaporated crystallization of 1640 solutions and some protein + salt solutions, we revealed for the first time the onset and dynamic process, the behavior, and general rules of the dendritic crystal growth as a function of temperature, pH value, and the concentrations of their major components (NaCl, KCl, NaHCO₃, and d-glucose). We proposed the crystallization mechanism for each of them at various conditions and indicated the factors that control the formation of dendritic crystals. We showed that at a temperature ranging from 20 to 40 °C, only the solution mixed with crystalline and amorphous substances could form dendritic crystals. The rise in temperature and decreasing pH from the neutral value would reduce the pattern divergence induced by different components and concentrations. Increasing the content of the crystalline substances would make the dendritic crystals thicker and have less branching. The dendritic crystals are mainly composed of the salt with the highest ratio R of concentration/solubility. The crystal structure of the salt also determines the shape of the dendrites. The amorphous substances mainly distribute at the edge of the dried spot to form a ring and deposit in the gaps between the dendritic crystals or the growing tips of the dendrites. This study suggests that based on the behavior of the dendrite growth, it is possible to use the methods of dendrite formation and pattern analysis to replace analytical instruments for some solution physicochemical tests or grow dendritic crystals with desired patterns for various applications.

Identification of the precursor cluster in thermolysin crystallization solution by molecular dynamics methods

An analysis of the crystal structure of thermolysin revealed four possible precursor clusters (hexamers) of its crystal. Using the method of molecular dynamics and plots of root mean square fluctuation, root mean square deviation and radius of gyration, the most stable hexamer, which is a precursor cluster,was determined. The importance of the established structure of the thermolysin precursor cluster for determining the mechanism of crystal formation is shown.

Amaranth calcium oxalate crystals are associated with chloroplast structures and proteins

Calcium oxalate (CaOx) crystals in plants are formed in crystal idioblasts cells and have specific geometric shapes. Their proposed functions include calcium homeostasis and carbon source, among others. Amaranth is a plant that presents high tolerance to abiotic stresses and accumulates considerable amounts of CaOx crystals; however, few studies have focused on characterizing the crystals ultrastructure and none is related to identifying proteins bound to them. This information is of great interest to understand the mechanisms related to CaOx crystal formation and to support their proposed functions. Thus, this work aimed to characterize CaOx crystals in amaranth leaves. Crystals were purified and the proteins bound to them were isolated and identified by nLC-MS/MS. Leaf sections were analyzed by light and electron microscopy. The identified proteins were related to the chloroplast such as ATPb synthase, RuBisCO large subunit, and cell wall-related proteins, which were validated by immunohistochemistry and immunogold labeling. In addition, it was observed that CaOx crystal idioblasts were formed from parenchyma cells associated with mesophyll and veins, in which the thylakoid membranes of degraded chloroplasts turned into crystal chambers. These results significantly advance our understanding of the mechanisms of CaOx crystal formation and the potential function as an alternative carbon source in leaves.

Modeling of a Continuous Carbonation Reactor for CaCO3 Precipitation

To stop global warming well below 2°C, a rapid decarbonization of our economy, including the industrial sector is required—reaching net-zero GHG emissions in 2050. CO2 mineralization processes, capturing CO2 from industrial point sources and trapping it as carbonate minerals, have the potential to store climate-relevant amounts of CO2. To get there, the potential processes have to be designed and developed, with the help of a process model that can support the process scale-up and optimization. In this work, a process model describing a gas-liquid-solid continuous cristallizer for CO2 absorption into an aqueous ammonium nitrate solution and CaCO3 precipitation has been developed. It consists of the relevant material balances, of a speciation model, and a population balance equation. While several of the model parameters can be obtained from the literature, a few have been estimated by fitting a comprehensive set of experimental data presented earlier. In particular, the process quantities used for parameter estimation are the CO2 mass transfer rate, the calcium carbonate crystallization rate, and the average particle size of the CaCO3 product crystals. The accuracy of the model, particularly in reproducing mass transfer rates and average particle sizes, has been assessed. Interestingly, it has been shown that the dominating mechanism for crystal formation is primary rather than secondary nucleation. The validated model has been used to explore the effect of the different operating conditions on various key performance indicators so as to gain a deeper insight into the process performance and potential. It has been shown that the CO2 absorption efficiency is mainly affected by the feed stoichiometry and the gas feed rate, whereas the CO2 capture and precipitation efficiency are controlled by the liquid phase composition and the residence time; increasing the calcium concentration in the feed is obviously one way to improve the efficiency. Moreover, we could show that the particle size tends to increase with calcium concentration and to decrease with liquid feed rate and supersaturation of the solution.

Medium-range structure motifs of complex iron oxides

Natural occurring iron oxides, such as Fe2O3, Fe3O4, and FeO, are abundant on Earth's surface and feature many implications in our daily life since the Iron Age, the final epoch of the prehistory of humanity. The physics of iron oxides is at the frontier of physical research due to their complicated magnetic and electronic properties. What makes it even more intriguing is the introduction of pressure, which not only regulates the crystal structures and physical properties, but also creates new iron-oxide stoichiometry. Recent studies discovered several novel iron-oxygen compounds under various pressure–temperature conditions. Despite different Fe/O ratios, those iron oxides are built upon similar structural units including FeO6 octahedra and trigonal prisms. Complex stoichiometry of pressurized iron oxides is built up by stacking layers of those FeO6 units, and in the medium-range, they are organized by certain structural motifs. In this perspective, we go beyond conventional iron-oxygen binary compounds and reveal the general formation mechanism of complex iron oxide crystals under high-pressure conditions. The results will be helpful for summarizing literary works of iron oxides and exploring novel stoichiometry with optimal physical properties.