Changes In Crystallinity Research Articles

Polycaprolactone-Based Composite Electrospun Nanofibers as Hybrid Biomaterial Systems Containing Hydroxyl- or Carboxylic Acid-Functionalized Multiwall Carbon Nanotubes

Composite electrospun nanofibers based on polycaprolactone (PCL) have shown promise in various biomedical applications due to their unique properties. This study investigates the effects of incorporating hydroxyl (–OH)- or carboxylic acid (–COOH)-functionalized multiwall carbon nanotubes (MWCNTs) into PCL matrices. Two types of functionalized additives, MWCNT-OH and MWCNT-COOH, were used at different concentrations (0.06 and 0.12 wt%). Various characterization techniques including FTIR, XRD, AFM, SEM, water contact angle analysis, and tensile strength testing were employed to evaluate changes in nanofiber morphology, crystallinity, surface topography, wettability, and mechanical properties. In addition, in vitro cytotoxicity assays were conducted using HUVECs and L929 fibroblasts over 1-, 3-, and 5-day intervals. This study represents a novel examination of (–OH)- and (–COOH)-functionalized MWCNTs as additives in electrospun PCL biopolymer matrices. The findings indicate that incorporating small amounts of (–OH)- or (–COOH)-functionalized MWCNTs enhances the physicochemical characteristics of PCL nanofibers, making them more suitable for biomedical applications. While both types of functionalized MWCNT additives improved properties compared to pure PCL nanofibers, (–COOH)-functionalized MWCNT-incorporated nanofibers exhibited the most favorable features. In conclusion, this research highlights the potential of tailored PCL-based composite nanofibers containing functionalized MWCNTs as advanced biomaterial systems for biomedical applications, contributing to the development of innovative biomaterials for diverse biomedical contexts.

Investigation of radiation-induced aromatization in high-density polyethylene and the product formations mechanism using molecular spectroscopy

The effects of 1.75 MeV N5+ ion beam irradiation of varying ion fluences, ranging from 1 × 1012 to 3 × 1014 ions/cm2, on high-density polyethylene have been done to investigate the structural, optical and chemical properties using X-ray diffraction (XRD), UV–visible spectroscopy and Fourier transform infrared (FTIR) spectroscopic techniques. XRD patterns show no significant change in crystallinity in irradiated polymer samples. The lattice plane and crystallite size of the irradiated polymer have not changed noticeably. More than 50% decrease in optical band gap were found for higher ion fluences of 3 × 1014 ions/cm2. UV–visible spectra show a red shift in absorption maxima due to the formation of extended conjugation. FTIR peaks 3646, 1707 and 2170 cm−1 in irradiated polymer were observed. The reaction mechanism chemistry of radiation-induced product formations, including chain scission, molecular crosslinking and hydroxyl, carbonyl and alkyne functional groups have been discussed.

Enhanced solubility and biological activities of Flufenamic acid through β-Cyclodextrin derivatives inclusion complexes: A comprehensive study

This study explores the formation of inclusion complexes between the solubility enhancement of Flufenamic acid (FNA) and various β-Cyclodextrins (β-CD, Hβ-CD, Mβ-CD, and Sβ-CD) using ultrasonic probe sonication method. The investigation encompasses a multi-faceted analysis, employing UV–Visible, FTIR, XRD, FE-SEM, TGA-DSC techniques and molecular docking studies. The UV–Visible spectra reveal absorption peak shifts and binding constants (Ka) indicate interaction strength, and thermodynamic parameters suggest spontaneous and favorable inclusion processes of β-CDs:FNA. Solid inclusion complexes of β-CDs:FNA were further characterized using FTIR, revealing alterations in functional groups indicative of complex formation. XRD analysis elucidates changes in crystallinity, while FE-SEM provides insights into morphological variations. Thermal stability is assessed through TGA-DSC, demonstrate the impact of inclusion on the complexes stability. Phase solubility diagrams illustrate the improved solubility of FNA in the presence of β-CDs. Mβ-CD:FNA exhibits the highest stability constant (1204 M−1), emphasizing its potential as an effective carrier. The binding energy of Mβ-CD:FNA (−46.72 kcal/mol) was lower than that of β-CD:FNA (−39.03 kcal/mol), Hβ-CD:FNA (−46.40 kcal/mol), and Sβ-CD:FNA (−46.29 kcal/mol), indicating that the hydroxypropyl group substitution enhanced the inclusion ability of β-CDs. Antibacterial activity studies against S. aureus and E. coli highlight enhanced efficacy of inclusion complexes with Mβ-CD:FNA (92.3 ± 0.18 % and 94.2 ± 0.17 %) demonstrating superior antibacterial activity. Cytotoxicity evaluations on HCT-116 cells reveal the safety profile of the β-CDs:FNA inclusion complexes, with Mβ-CD:FNA showing lower toxicity and high cell internalization compared to other formulations. The findings hold promise for applications in drug delivery, antimicrobial packaging, and the broader pharmaceutical and biotechnological fields.

On the Role of Starchy Grains in Ice Nucleation Processes.

Little is known about the role of starchy food on climate change processes like ice nucleation. Here, we investigate the ice nucleation efficiency (INE) of eight different starchy food materials, namely, corn (CO), potato (PO), barley (BA), brown rice (BR), white rice (WR), oats (OA), wheat (WH), and sweet potato (SP), in immersion freezing mode under mixed-phase cloud conditions. Notably, among all these food materials, PO and BA exhibit the highest ice nucleation efficiency with ice nucleation temperatures as high as -4.3 °C (T50 ∼ -7.0 ± 0.5 °C) and -6.5 °C (T50 ∼ -7.2 ± 0.2 °C), respectively. We also explore the effect of environmentally relevant physicochemical conditions on ice nucleation efficiency, including different pH, temperature, UV/O3/NOx exposure, and various cocontaminants. The change in shape, size, surface properties, hydrophobicity, and crystallinity of materials accounted for the altered INE. The increase in shape, size, and hydrophobicity of the sample generally reduces the INE, whereas an increase in crystallinity enhances the INE of the sample under our experimental conditions. The results suggest that environmentally relevant concentrations slightly alter INE, indicating their role as catalysts in environmental matrices. The outcome of studies on the ice nucleation properties of these food-containing aerosols might help in the physicochemical understanding of other biomolecule-induced ice nucleation, which is still an underdeveloped research area.

Effects of photodegradation performance with PLA‐containing samples on double injection molding

AbstractThe influence of different overlay layers (ABS, PC, and PLA) is investigated on the photodegradation behavior of poly(lactic acid) (PLA)‐containing samples in double injection molding, and PLA/PLA samples serve as the control group. In terms of microstructure, an analysis is conducted on the chemical structure, thermal performance, crystallinity, and molecular weight of the base layer of samples. The carbonyl index and molecular weight of the base layer of PLA/PLA samples decrease rapidly, and the trend of crystallinity change is also fast. Among them, the number of molecular chain scissions decreases to 0.61, and the crystallinity increases to a maximum of 17.93%, which indicates that the photodegradation degree of the base layer of PLA/PLA samples is greater than that of the other two samples. The microscopic surface morphology change of the base layer of three PLA‐containing samples is analyzed. The base layer of PLA/PLA samples becomes rougher after 600 h of UV degradation. Meanwhile, compared with other PLA‐containing samples, the percentage of tensile strength loss of PLA/PLA samples is higher, decreasing by 16.64%. In summary, using acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) materials as overlay layers for double injection molding can mitigate the photodegradation of the base layer of PLA‐containing samples in double injection molding.

Effect of Ce2O3 phase transition on the catalytic oxidation for toluene over CeO2 catalysts

Cerium oxide was a potential replacement for precious metals as a catalyst for VOCs. Here, we prepared CeOx-350, CeOx-450, CeOx-550 and CeOx-650 catalysts by controlling the calcination temperature, the occurrence of Ce2O3 localized phase transitions at CeOx-350 and CeOx-550 was confirmed by XRD, HRTEM and TGA. This localized phase transition caused the change in specific surface area and crystallinity, and prolonged the Ce-O-Ce bond lengths at the heterogeneous interfaces, enhancing the redox capacity and activity of oxygen species. CeOx-550 exhibited the optimal low-temperature activity towards toluene due to the highest Ce3+ content, oxygen vacancy content and the best activity of reactive oxygen species. The oxidation of toluene experienced intermediates of benzyl alcohol, benzaldehyde, benzoate, maleic acid and carbonates. Among them, benzoic acid was the decisive step in the toluene oxidation pathway. Combined with the reaction pathway of toluene, the reaction stages of different oxygen species were determined. The active oxygen species located at the heterogeneous interface would serve as an adsorption site for toluene. The Ce2O3 phase would participate in the deep oxidation of toluene as an active site, which was equivalent to the oxygen vacancies. This study was conducted to explore the effect of local phase transition on catalytic activity, which provided a new strategy for the synthesis of highly active cerium oxide catalysts.

Effects of chlorine and nitro groups on the crystal structure of novel 4-quinolinone derivatives from sulfonamide chalcone

This study explores the impact of introducing chlorine and nitro groups into two novel quinolone derivatives, (E)-3-(4-nitrobenzylidene)-2-(3-nitrophenyl)-2,3-dihydro-1-(phenylsulfonyl)-quinolin-4(1H)-one (NPQ) and (E)-3-(4-chlorobenzylidene)-2-(3-nitrophenyl)-2,3-dihydro-1-(phenylsulfonyl)-quinolin-4(1H)-one (CPQ), using experimental techniques and density functional theory (DFT). The research focuses on crystalline packing, conformational changes, and intermolecular interactions. The investigation reveals that weak non-classical hydrogen interactions, hydrophobic, and CH···π interactions, predominantly stabilize the crystal structures. These interactions, quantified through a Hirshfeld surface analysis. Additionally, the Fukui function analysis indicates antioxidant potential in the crystals. NPQ and CPQ exhibit a small energy gap, implying low kinetic stability, high reactivity, and reduced resistance to charge transfer when compared. These findings provide valuable insights into the structural and electronic properties of these quinolone derivatives, aiding the design of novel compounds with desired characteristics and applications. The DFT analysis utiliazsed the M062-X functional and the 6–311++G(d,p) basis set in the Gaussian 09 package, and the result was visualized using the GaussView software.

Investigations on Impact of YSZ Nanoparticles on Morphology & Electrical conductivity of PEDOT: PSS

Conductive polymer nanocomposites, which combine the flexibility and conductivity of polymers with the unique properties of nanofillers, have generated interest in various fields such as energy storage, sensors, coatings, and corrosion protection. This study discusses the effect of Yttria-stabilized zirconium nanoparticles (YSZ NPs) on the morphology and electrical conductivity of poly(3,4-ethylenedioxythiophene): poly(4-styrenesulfonate) (PEDOT: PSS). Thin films of PEDOT: PSS and PEDOT: PSS: YSZ were fabricated using spin coating technique. FTIR and XRD characterizations confirmed the interaction between YSZ nanoparticles and the PEDOT: PSS matrix, leading to changes in chemical morphology and film crystallinity. The investigation of the current-voltage (I-V) relationship showed improved electrical conductivity in PEDOT: PSS films with the addition of YSZ nanoparticles, with respective conductivities of 0.028×10−6 S cm−1 and 0.0885×10−4 S cm−1 for pristine and YSZ-containing films. Additionally, the sensing properties of the PEDOT: PSS: YSZ film in detecting organic vapours were studied. These findings suggest that these conducting polymer nanocomposite thin films could potentially be used as electrolyte components in battery cells, supercapacitors, and fuel cells, as well as serve as sensors for certain organic vapours.

The Optimization of the Steam-Heat-Treated Process of Rattan (Calamus simplicifolius) Based on the Response Surface Analysis and Its Chemical Changes

The objective of this study is to investigate the impacts of steam heat treatment parameters (e.g., temperature, time, and pressure) on the impact toughness of rattan (Calamus simplicifolius). The Box–Behnken design response surface analysis was employed to optimize the steam heat treatment parameters. Impact toughness was selected as the evaluation index, with single-factor tests conducted as a baseline for comparison. Changes in chemical composition, cellulose crystallinity, and pyrolysis properties were analyzed using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectra, Thermogravimetry–Fourier transform infrared (TG-FTIR) spectra, and wet-chemistry methods for both untreated control samples and the heat-treated samples. The results show that a 1 h steam heat treatment at 160 °C under 0.1 MPa pressure has the optimal process parameters for the rattan. The achieved impact toughness value closely matches the predicted value at 71.29 kJ/m2. After the steam heat treatment, hemicellulose and cellulose contents decrease, whereas relative lignin content increases significantly, leading to improved toughness characteristics in Calamus simplicifolius samples. The TG results indicate that maximum weight loss occurs at temperatures of 352 °C, 354 °C, and 361 °C, respectively, for three different samples. This suggests that the thermal stability is enhanced as a result of the heat treatment. These findings will help optimize the heat treatments of the rattan material.

Comparative Analysis of the Effects of Incorporating Post-Industrial Recycled LLDPE and Post-Consumer PE in Films: Macrostructural and Microstructural Perspectives in the Packaging Industry.

In accordance with the Circular Economy Package of the European directive, the Spanish government compels manufacturers of plastic bags to include into their products a minimum of 70% of polyethylene (PE) waste. Following this mandate can be challenging and requires a deep knowledge of the alterations produced by the recycling in the main components of a plastic bag film: lineal low-density polyethylene (LLDPE), the LLDPE recycled post-industry, generated as waste from an industrial process (rLLDPE) and the PE recycled from post-consumer use (rPE), that has been picked up, cleaned, and reprocessed. This study provides insight in the macro and microstructural changes produced by several cycles of recycling in these materials. Specimens in the form of film for supermarket bags formed with these polymers have been subjected to several recycling sequences. The process closely mimics industrial processes. Four cycles have been applied to the samples. The evolution of mechanical properties, including tensile strength, elongation at break, and tear and impact tests, shows an obvious decrease due to degradation that is not an impediment for practical use after the four cycles of recycling according to the main specifications defined by the producer. Colorimetric measurements reveal no significant variations in the color of the films. The results of the FTIR and TGA analysis show degradation phenomena and changes in crystallinity in branching and the apparition of crosslinking that are in consonance with the mechanical data. There is also a difference between both types of recycled PE. In general, rLLDPE is more affected by the recycling than rPE. According to our findings, the limiting property would be the tearing. By comparing these values with bags available in the market, manufactured from 70-80% recycled material, we can infer that while two reprocessing cycles can lead to good results, a maximum of four cycles of recycling is advisable.

Topographical and crystalline change on surface by sandblasting improve flexural and shear bond strength of niobia-modified yttria-stabilized tetragonal zirconia polycrystal.

This study aimed to investigate the effects of sandblasting on the physical properties and bond strength of two types of translucent zirconia: niobium-oxide-containing yttria-stabilized tetragonal zirconia polycrystals ((Y, Nb)-TZP) and 5 mol% yttria-partially stabilized zirconia (5Y-PSZ). Fully sintered disc specimens were either sandblasted with 125 µm alumina particles or left as-sintered. Surface roughness, crystal phase compositions, and surface morphology were explored. Biaxial flexural strength (n=10) and shear bond strength (SBS) (n=12) were evaluated, including thermocycling conditions. Results indicated a decrease in flexural strength of 5Y-PSZ from 601 to 303 MPa upon sandblasting, while (Y, Nb)-TZP improved from 458 to 544 MPa. Both materials significantly increased SBS after sandblasting (p<0.001). After thermocycling, (Y, Nb)-TZP maintained superior SBS (14.3 MPa) compared to 5Y-PSZ (11.3 MPa) (p<0.001). The study concludes that (Y, Nb)-TZP is preferable for sandblasting applications, particularly for achieving durable bonding without compromising flexural strength.

Removable Additive Assists Blade‐Coated Large‐Area Organic Solar Cell Modules Fabricated with Non‐Halogenated Solvents Achieving Efficiency Over 16%

AbstractThe critical step in commercializing organic solar cells (OSCs) involves achieving high‐performance modules through environmentally friendly solvents. The incorporation of solid additives, recognized as an effective method for modulating the morphology of active layers through layer‐by‐layer (LBL) deposition, plays a significant role. Here, a novel volatile solid additive is introduced individually into the non‐halogenated solution of donor PM6 as a morphology‐modulating agent. The additive induces conformational and crystalline orientation change of PM6, resulting in enhanced and balanced charge transport in the active layer. With a focus on exciton dynamics, the optimized active layer inhibits the formation of low‐energy triplet states. It facilitates strong reverse hole transfer processes, leading to more efficient exciton dissociation. The final small‐area LBL blade‐coated OSCs fabricated under ambient conditions achieve a power conversion efficiency (PCE) of 18.42%. Furthermore, a large‐area module with an area of 28.82 cm2 is manufactured, achieving a PCE of 16.04% with a high geometric fill factor of 93.8%. This highlights the effective modulation of the active layer through the use of solid additives and provides a successful strategy for fabricating high‐performance OSC modules with non‐halogenated solvents.

Application of Response Surface Methodology Using Face-centered Central Composite Design for Studying Long-Term Stability of Gliclazide-Loaded Multiparticulate Systems

The appropriate design of experiments (DoE) could support post-approval lean-stability approaches. A three-factor three-level face-centered design was constructed to evaluate the long-term stability of gliclazide (GLZ) alginate-gelatin beads. The formulation variables were GLZ%(X1), alginate:gelatin ratio(X2), and glutaraldehyde%(X3). The studied responses included GLZ release at predefined intervals in 0.1 N HCl (2 h) followed by phosphate buffer (pH 7.4). Model-dependent and independent approaches were utilized for comparison. DoE-model validation and reduction were implemented. All the studied formulations showed non-significant changes in the particle size (p > 0.05) and most of them showed similar release profiles before and after storage. The directions of the relationships between the factors' main effects and the responses (Y1:Q0.5h, Y2:Q2h, and Y3:Q4h) remained unchanged after storage. The optimal factor settings based on the proposed optimization criteria were defined. The optimized formulations (OP-1 and OP-2) showed non-significant changes in the particle size after storage. The release profiles and kinetics of OP-1 and OP-2 remained unchanged after storage. No chemical change was indicated (FT-IR). DSC-thermograms of OP-1 indicated GLZ conversion to a more stable polymorph after storage. While OP-2 showed a change in GLZ crystallinity. The stored and fresh beads’ surfaces after GLZ release were almost similar. DoE could be utilized to evaluate, optimize, and predict the effects of different formulation variables on the long-term stability of GLZ alginate-gelatin beads.

Changes in the structure and enzyme binding of starches during in vitro enzymatic hydrolysis using mammalian mucosal enzyme mixtures

Starches are hydrolyzed into monosaccharides by mucosal α-glucosidases in the human small intestine. However, there are few studies assessing the direct digestion of starch by these enzymes. The objective of this study was to investigate the changes in the structure and enzyme binding of starches during in vitro hydrolysis by mammalian mucosal enzymes. Waxy maize (WMS), normal maize (NMS), high-amylose maize (HAMS), waxy potato (WPS), and normal potato (NPS) starches were examined. The order of the digestion rate was different compared with other studies using a mixture of pancreatic α-amylase and amyloglucosidase. NPS was digested more than other starches. WPS was more digestible than WMS. Hydrolyzed starch from NPS, NMS, WPS, WMS, and HAMS after 24 h was 66.4, 64.2, 61.7, 58.7, and 46.2 %, respectively. Notably, a significant change in the morphology, reduced crystallinity, and a decrease in the melting enthalpy of the three starches (NPS, NMS, and WPS) after 24 h of hydrolysis were confirmed by microscopy, X-ray diffraction, and differential scanning calorimetry, respectively. The bound enzyme fraction of NPS, NMS, and WPS increased as hydrolysis progressed. In contrast, HAMS was most resistant to hydrolysis by mucosal α-glucosidases in terms of digestibility, changes in morphology, crystallinity, and thermal properties.

Hydrothermal aging behavior of high‐performance polymeric fibers: Mechanical performance at the yarn scale and chemical analysis

AbstractHigh‐performance fibers are used in fire‐protective garments due to their exceptional thermal stability and mechanical performance. However, these garments suffer from a reduction in their performance over their lifetime. The purpose of this study was to investigate the hydrothermal aging of 15 yarns contained in eight fabrics made of different fiber blends. The accelerated hydrothermal aging was performed via immersion in reverse osmosis (RO) and acidic water at temperatures between 40 °C and 90 °C for up to 1200 h. The resulting mechanical, chemical, and physicochemical changes in the yarns and fabrics were assessed. The result showed a large drop in the breaking force of yarns made from para‐aramid/polybenzimidazole (PBI) fiber blends in all aging water conditions. For the other fabrics, aging in acidic water and a jar with the PBI‐containing fabrics generally caused a larger decrease in strength compared to aging in RO water in a separate jar. The results also showed that a change in crystallinity rather than in chemical structure appeared to be the cause for the changes in tensile strength after hydrothermal aging. The findings of this study will contribute to identifying strategies to improve the long‐term performance of fire‐protective fabrics.

Orbital Occupancy Modulation to Optimize Intermediate Absorption for Efficient Electrocatalysts in Water Electrolysis and Zinc-Ethanol-Air Battery.

Spin engineering is a promising way to modulate the interaction between the metal d-orbital and the intermediates and thus enhance the catalytic kinetics. Herein, an innovative strategy is reported to modulate the spin state of Co by regulating its coordinating environment. o-c-CoSe2 -Ni is prepared as pre-catalyst, then in situ electrochemical impedance spectroscopy (EIS)and in situ Raman spectroscopy are employed to prove phase transition, and CoOOH/Co3 O4 is formed on the surface as active sites. In hybrid water electrolysis, the voltage has a negative shift, and in zinc-ethanol-air battery, the charging voltage is lowered and the cycling stability is greatly increased. Coordinated atom substitution and crystalline symmetry change are combined to regulate the absorption ability of reaction intermediates with balanced optimal adsorption. Coordinated atom substitution weakens the adsorption while the crystalline symmetry change strengthens the adsorption. Importantly, the tetrahedral sites are introduced by Ni doping which enables the co-existence of four-coordinated sites and six-coordination sites in o-c-CoSe2 -Ni. The dz2 + dx2 -y2 orbital occupancy decreases after the atomic substitution, while increases after replacing the CoSe6 -Oh field with CoSe6 -Oh /CoSe4 -Td . This work explores a new direction for the preparation of efficient catalysts for water electrolysis and innovative zinc-ethanol-air battery.

Study of the surface, rheological and morphological characteristics of isotactic polypropylene microplastics aged in a photothermal oxidation chamber

The aim of this study was to investigate, in addition to degradation processes, the rheological, crystalline, and molecular dynamics changes in isotactic polypropylene microplastics with average sizes of 0.5 and 2 mm, aged in a photothermal oxidation chamber for 166 days. In addition to commonly used techniques in microplastics research, time-domain nuclear magnetic resonance (TD-NMR) in fast field cycling and fixed field modes, was employed for the first time in the study of these materials, providing non-destructive information that supports other results. Concurrently with X-ray diffractometry (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), rheometry, Fourier-transform infrared spectroscopy (FTIR), surface wettability, and scanning electron microscopy (SEM) techniques, two antagonistic phenomena were observed over the aging period. One associated with the surface degradation of microplastics and increased molecular mobility, and the other related to morphological changes in the internal layers, leading to increased rigidity. These phenomena occur slightly differently depending on the average particle size. Through multivariate data analysis with principal component analysis (PCA) and hierarchical cluster analysis (HCA), it was possible to determine that the degradation process intensifies after 62 days of simultaneous exposure to ultraviolet radiation, temperature, and oxidizing atmosphere. The obtained data highlight that even synthetic polymers with long degradation periods can undergo, in the form of microplastics, initial morphological changes in just 15 days and degradation processes within a few months of exposure to weathering conditions.

The impact of parboiling on physical structure, physicochemical properties and zinc status of Zn-fortified germinated brown rice

The structural and physicochemical properties, cooking quality and zinc retention ratio of Zn-fortified germinated brown rice were investigated with different parboiling times (4–20 min). The brown rice grains exhibited visually more yellowish-brown colour and cracks on the surface with the germination and longer parboiling, and the micrographs clearly displayed wrinkles after these processes. Germination and the increase of parboiling time exacerbated the disruption of microstructure and the decrease in relative crystallinity and enthalpy change. The relaxation time (T2) increased in Zn-fortified germinated brown rice and parboiled samples compared to brown rice. Cooking time of Zn-fortified germinated brown rice was reduced from 36 min to 27 min with longer parboiling. Parboiling treatment longer than 4 min improved the palatability. There was no significant difference of Zinc retention ratio at different parboiling times. Sixteen min parboiling was recommended to obtain the brown rice product, which requires a short cooking time with desired palatability, as well as acceptable colour and zinc content. Overall, parboiling is an effective technique to modify the physical structure and physicochemical properties and improve cooking quality of Zn-fortified germinated brown rice.

Influence of 3D printed surface micro-structures on molding performance and dental bonding properties of zirconia

ObjectivesTo investigate the influence of the 3D printed micro-structured surfaces on the bond strength of zirconia to resin cement. MethodsZirconia specimens were divided into five groups based on manufacturing technique and surface preparation: (1) milled zirconia (M group); (2) milled zirconia airborne abraded (MA group); (3) printed zirconia (M group); (4) printed zirconia airborne abraded (PA group); and (5) printed zirconia with micro-structured surface (PM group). The surface morphology, cross-sectional morphology, and elemental composition were observed using a scanning electron microscope (SEM). Surface roughness was measured using a laser scanning confocal microscope (SLCM). Shear bond strength (SBS) was measured using a universal testing machine after bonding resin cement (n = 10). The failure modes of the bonded fracture interfaces were observed and counted using a stereomicroscope and a SEM. In addition, boundary dimensional accuracy (n = 10) and micro-structural dimensional accuracy (n = 20) of printed zirconia specimens with micro-structured surfaces were measured using digital calipers and Fiji software. The crystalline phase changes before and after surface treatment were investigated using X-ray diffractometry. Data was analysed using one-way ANOVA and Tukey HSD post-hoc tests (α = 0.05). ResultThe surface micro-structures of the PM group had regular morphology and no obvious defects. The surface roughness results showed that the PM group had higher Sa (42.21±1.38 um) and Ra (21.25±1.80 um) values than the other four groups (p < 0.001). The SBS test showed that the bond strength of the PM group reached 11.23 ± 0.66 MPa, which was 55.97% (p < 0.001) higher than that of the P group (7.20 ± 1.14 MPa). The boundary dimensional accuracy of the PM group was proficient (diameter: 99.63 ± 0.31%, thickness: 98.05 ± 1.12%), and the actual fabrication dimensions of the hexagonal micro-structures reached 77.45%-80.01% of the original design. The micro-structured surface did not affect the crystalline phase of zirconia. ConclusionsThe current study illustrates that 3D-printed microstructured surfaces effectively improve the bond strength of zirconia to resin cements. Clinical significanceWith the advantage of 3D printing, this study provides a new idea for improving the bonding properties of zirconia.

Imidazole as a new strategy in the lignocellulosic pretreatment: An application in corn sub-products with a focus on bioenergy production

To enhance the efficiency of pretreatment processes for lignocellulosic biomass, this study utilized the green solvent imidazole to pretreat residual corn biomass (corn straw (CS) and corncob (CC)) with a focus on cellulose recovery for ethanol production. The pretreatment involved varying temperatures (ranging from 120 to 180 °C) and times (30 and 60 min) with biomass:imidazole ratio of 1:9 (w.w−1). The effects of imidazole pretreatment on the biomasses were examined by analyzing the chemical composition, surface morphology, cellulose crystallinity, and compositional changes. The results demonstrated a significant alteration of the lignocellulosic complex due to imidazole pretreatment, resulting in a reduction of the lignin content, reaching 81.47 % and 74 % for CS (180°C-60min) and CC (180°C-30min), respectively. Moreover, the cellulose content in the pretreated solids increased by approximately 1.5 times compared to the raw biomass. The pretreated biomasses were subjected to enzyme hydrolysis (after pretreated at a higher temperature (150–180 °C)), which led to a high glucose yield. CC achieved a glucose yield of 100 %, while CS yielded 77 %. Alcoholic fermentation was carried out using Saccharomyces cerevisiae CAT-1, resulting in an ethanol yield of 82 % in 12 h for CC (180 °C for 30 min) and 66 % for CS (150 °C for 1 h).