Resistive switching behavior and improved multiferroic properties of Bi0.9Er0.1Fe0.98Co0.02O3/Co1-xMnxFe2O4 bilayered thin films

Bilayered Bi_0.9Er_0.1Fe_0.98Co_0.02O₃/Co_1-xMn_xFe₂O₄ (BEFCO/CM_xFO) thin films were deposited by the sol-gel method. Structural variations between the triclinic-P1 and trigonal-R3c:H (two-phase coexistence) phases in the BEFCO layer were observed owing to the trigonal-R-3m:H phase existing in the CM_xFO layer. The oxygen vacancy concentrations of the BEFCO/CM_xFO bilayered films are reduced by Mn-doping in the bottom CFO layer. The BEFCO/CFO films showed high oxygen vacancy concentrations with a high leakage current. This induced changes of the significant potential barrier at the interface between the BEFCO and CM_xFO layers in the processes of electron capture and release. Thus, the BEFCO/CFO film exhibited obvious resistive switching (RS) effect. The high leakage current also caused a fake polarization phenomenon with a blow up of the P-E loop in the BEFCO/CFO films. However, the real and outstanding ferroelectric properties, which resulted from the fewer oxygen vacancies and the 38% triclinic-P1 structure, were obtained in the BEFCO/CM_0.3FO films (P_r~156.3?μC?cm^?2). In addition, the typical capacitance-voltage curve further confirmed its superior ferroelectric performance. The RS effect almost disappeared in the BEFCO/CM_0.3FO bilayered films. Moreover, the enhanced ferromagnetic properties (M_s~100.36?emu?cm^?3, M_r~55.38?emu?cm^?3) were obtained for the BEFCO/CM_0.1FO films, which was attributed to the magnetic properties of BEFCO (a more triclinic-P1 phase and numerous Fe²⁺ ions), in addition to the CM_xFO layer. The introduction of the doped magnetic layer into the bilayered films thus represented a highly effective method for enhancing the multiferroic properties of BFO.     

Exogenous Melatonin Enhances Photosynthetic Capacity and Related Gene Expression in A Dose-Dependent Manner in the Tea Plant (Camellia sinensis (L.) Kuntze)

The enhancement of photosynthesis of tea leaves can increase tea yield. In order to explore the regulation mechanism of exogenous melatonin (MT) on the photosynthetic characteristics of tea plants, tea variety ‘Zhongcha 108’ was used as the experimental material in this study. The effects of different concentrations (0, 0.2, 0.3, 0.4 mM) of melatonin on the chlorophyll (Chl) content, stomatal opening, photosynthetic and fluorescence parameters, antioxidant enzyme activity, and related gene expression of tea plants were detected and analyzed. The results showed that under 0.2-mM MT treatment, chlorophyll (Chl) content, photosynthetic rate (P_n), stomatal conductance (G_s), intercellular CO₂ concentration (C_i), and transpiration rate (T_r) improved, accompanied by a decrease in stomata density and increase in stomata area. Zero point two millimolar MT increased Chl fluorescence level and superoxide dismutase (SOD) activity, and reduced hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) contents, indicating that MT alleviated PSII inhibition and improved photochemical efficiency. At the same time, 0.2 mM MT induced the expression of genes involved in photosynthesis and chlorophyll metabolism to varying degrees. The study demonstrated that MT can effectively enhance the photosynthetic capacity of tea plants in a dose-dependent manner. These results may promote a comprehensive understanding of the potential regulatory mechanism of exogenous MT on photosynthesis in tea plants.     

Splice-Variant Knock-Out of TGFβ Receptors Perturbates the Proteome of Ovarian Carcinoma Cells

The aim of this study was to analyze the biological role of different transforming growth factor-β (TGFβ) receptor splice variants in ovarian carcinoma (OC). Specific receptor variant knockouts (KO) were prepared using the CRISPR/Cas9 genome editing system in two OC cell lines, TβRI variant 1 (TβRIv1) KO in ES-2 cells and TβRII variant 1 (TβRIIv1) KO in OVCAR-8 cells. Control and KO cells were compared by proteomic analysis, functional tests, analysis of epithelial–mesenchymal transition (EMT) drivers, and Western blot of signaling proteins. Proteomic analysis revealed significant changes in protein pathways in the KO cells. TβRIv1 KO resulted in a significant reduction in both cellular motility and invasion, while TβRIIv1 KO significantly reduced cellular motility and increased Reactive Oxygen Species (ROS) production. Both receptor variant KOs reduced MET protein levels. Of the EMT drivers, a significant decrease in TWIST protein expression, and increase in SNAIL protein and MALAT1 mRNA levels were observed in the TβRIIv1 KO compared to control. A significant decrease in JNK1 and JNK2 activation was found in the TβRIv1 KO compared to control cells. These findings provide new insight regarding the biological role of the TGFβ receptor variants in the biology and potentially the progression of OC.     

Trichodermin Induces G0/G1 Cell Cycle Arrest by Inhibiting c-Myc in Ovarian Cancer Cells and Tumor Xenograft-Bearing Mice

Ovarian cancer is a fatal gynecological cancer because of a lack of early diagnosis, which often relapses as chemoresistant. Trichodermin, a trichothecene first isolated from Trichoderma viride, is an inhibitor of eukaryotic protein synthesis. However, whether trichodermin is able to suppress ovarian cancer or not was unclear. In this study, trichodermin (0.5 µM or greater) significantly decreased the proliferation of two ovarian cancer cell lines A2780/CP70 and OVCAR-3. Normal ovarian IOSE 346 cells were much less susceptible to trichodermin than the cancer cell lines. Trichodermin predominantly inhibited ovarian cancer cells by inducing G0/G1 cell cycle arrest rather than apoptosis. Trichodermin decreased the expression of cyclin D1, CDK4, CDK2, retinoblastoma protein, Cdc25A, and c-Myc but showed little effect on the expression of p21^Waf1/Cip1, p27^Kip1, or p16^Ink4a. c-Myc was a key target of trichodermin. Trichodermin regulated the expression of Cdc25A and its downstream proteins via c-Myc. Overexpression of c-Myc attenuated trichodermin’s anti-ovarian cancer activity. In addition, trichodermin decelerated tumor growth in BALB/c nude mice, proving its effectiveness in vivo. These findings suggested that trichodermin has the potential to contribute to the treatment of ovarian cancer.     

Melatonin as a Signaling Molecule for Metabolism Regulation in Response to Hypoxia in the Crab Neohelice granulata

Melatonin has been identified in a variety of crustacean species, but its function is not as well understood as in vertebrates. The present study investigates whether melatonin has an effect on crustacean hyperglycemic hormone (CHH) gene expression, oxygen consumption (VO₂) and circulating glucose and lactate levels, in response to different dissolved-oxygen concentrations, in the crab Neohelice granulata, as well as whether these possible effects are eyestalk- or receptor-dependent. Melatonin decreased CHH expression in crabs exposed for 45 min to 6 (2, 200 or 20,000 pmol·crab⁻¹) or 2 mgO₂·L⁻¹ (200 pmol·crab⁻¹). Since luzindole (200 nmol·crab⁻¹) did not significantly (p > 0.05) alter the melatonin effect, its action does not seem to be mediated by vertebrate-typical MT1 and MT2 receptors. Melatonin (200 pmol·crab⁻¹) increased the levels of glucose and lactate in crabs exposed to 6 mgO₂·L⁻¹, and luzindole (200 nmol·crab⁻¹) decreased this effect, indicating that melatonin receptors are involved in hyperglycemia and lactemia. Melatonin showed no effect on VO₂. Interestingly, in vitro incubation of eyestalk ganglia for 45 min at 0.7 mgO₂·L⁻¹ significantly (p < 0.05) increased melatonin production in this organ. In addition, injections of melatonin significantly increased the levels of circulating melatonin in crabs exposed for 45 min to 6 (200 or 20,000 pmol·crab⁻¹), 2 (200 and 20,000 pmol·crab⁻¹) and 0.7 (200 or 20,000 pmol·crab⁻¹) mgO₂·L⁻¹. Therefore, melatonin seems to have an effect on the metabolism of N. granulata. This molecule inhibited the gene expression of CHH and caused an eyestalk- and receptor-dependent hyperglycemia, which suggests that melatonin may have a signaling role in metabolic regulation in this crab.     

Preparation and electromagnetic properties of the BaFe12O19/multiwall carbon nanotubes/poly(3‐methyl‐thiophene) composites

The BaFe₁₂O₁₉/multiwall carbon nanotubes/poly(3‐methyl‐thiophene) (BaFe₁₂O₁₉/MCNTs/P(3MT)) composites were synthesized through an in situ chemical polymerization of 3‐methyl‐thiophene (3MT) in the presence of BaFe₁₂O₁₉/MCNTs composite powders. The BaFe₁₂O₁₉/MCNTs/P(3MT) composites were characterized by the fourier transform infrared spectrometry (FTIR) and X‐ray diffraction (XRD). The morphologies of the composites were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electric conductive properties were tested by a four‐probe conductivity tester and the magnetic properties were measured by vibrating sample magnetometer (VSM). The electromagnetic performance tests showed that when the mass ratio of BaFe₁₂O₁₉ to MCNTs was 0.4, and the BaFe₁₂O₁₉/MCNTs to P(3MT) was 0.15, the conductivity, saturation magnetization (M_s) and residual magnetization (M_r) of the BaFe₁₂O₁₉/MCNTs/P(3MT) composites achieved 166.740 S/m, 29.884 emu/g, and 17.581 emu/g, respectively. POLYM. COMPOS., 34:1801–1808, 2013. © 2013 Society of Plastics Engineers     

Synthesis of CaO·2MgO·8Al2O3 (CM2A8) and its slag resistance mechanism

CM₂A₈ is a solid solution of MA and CA₆. As a component in the ternary phase diagram of CaO-Al₂O₃-MgO, it was not reported in detail. So in this work, analytically pure CaO, MgO and Al₂O₃ were adopted as starting materials and batched stoimotrically according to CM₂A₈. The raw materials were ground, mixed, shaped and reaction-sintered at different temperatures (1550 °C, 1650 °C, 1700 °C, and 1750 °C) to synthesize CM₂A₈. The synthesized specimens were analyzed by XRD, SEM, and TEM and the corrosion mechanism against LF slag was also researched. The results show that high-purity CM₂A₈ can be synthesized by reaction sintering at 1750 °C. During synthesis, granular MA and flake CA₆ form and grow together; at 1650 °C, they solid-solve together to form C₂M₂A₁₄. As the temperature rises, solid solution reaction goes on, which results in the disappearance of CA₆, C₂M₂A₁₄, and MA in succession and forms high-purity CM₂A₈ growing towards hexagonal column crystals. In the high temperature reaction between CM₂A₈ and steel slag, Ca²⁺ in the slag reacts with CM₂A₈ to form CA₂, damaging the structure of CM₂A₈ and releasing excessive Mg²⁺ and Al³⁺ which move towards the molten slag. As the reaction between Ca²⁺ and CM₂A₈ proceeds, a dense CA₂ coating forms on the surface of CM₂A₈. The slag viscosity increases as well because of the entrance of Mg²⁺ and Al³⁺. Thus, the formation of the CA₂ coating and the enhancement of the slag viscosity restrain the penetration and corrosion of slag towards CM₂A₈.     

Melatonin Suppresses the Growth of Ovarian Cancer Cell Lines (OVCAR-429 and PA-1) and Potentiates the Effect of G1 Arrest by Targeting CDKs

Melatonin is found in animals as well as plants. In animals, it is a hormone that anticipates the daily onset of darkness and regulates physiological functions, such as sleep timing, blood pressure, and reproduction. Melatonin has also been found to have anti-tumor properties. Malignant cancers are the most common cause of death, and the mortality rate of ovarian tumor is the highest among gynecological diseases. This study investigated the anti-tumor effects of melatonin on the ovarian cancer lines, OVCAR-429 and PA-1. We observed the accumulation of melatonin-treated cells in the G₁ phase due to the down-regulation of CDK 2 and 4. Our results suggest that in addition to the known effects on prevention, melatonin may also provide anti-tumor activity in established ovarian cancer.     

Melatonin Receptor Genes in Vertebrates

Melatonin receptors are members of the G protein-coupled receptor (GPCR) family. Three genes for melatonin receptors have been cloned. The MT1 (or Mel1a or MTNR1A) and MT2 (or Mel1b or MTNR1B) receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype, Mel1c (or MTNR1C), has been identified in fish, amphibians and birds. Another melatonin related orphan receptor, GPR50, which does not bind melatonin, is found exclusively in mammals. The hormone melatonin is secreted primarily by the pineal gland, with highest levels occurring during the dark period of a circadian cycle. This hormone acts systemically in numerous organs. In the brain, it is involved in the regulation of various neural and endocrine processes, and it readjusts the circadian pacemaker, the suprachiasmatic nucleus. This article reviews recent studies of gene organization, expression, evolution and mutations of melatonin receptor genes of vertebrates. Gene polymorphisms reveal that numerous mutations are associated with diseases and disorders. The phylogenetic analysis of receptor genes indicates that GPR50 is an outgroup to all other melatonin receptor sequences. GPR50 may have separated from a melatonin receptor ancestor before the split between MTNR1C and the MTNR1A/B ancestor.     

Lactose hydrolyzed milk powder: Thermodynamic characterization of the drying process

Industrial production of lactose hydrolyzed milk powder (LHMP) remains challenging. Due to the presence of the monosaccharides glucose and galactose, lactose-free powders tend to suffer stickiness, caking, and browning during drying and storage. We sought to find ideal conditions spray dryer inlet air temperature (θ_air,in) and concentrated milk flow rate (m_CM) for LHMP production. We tested θ_air,in settings of 115–160°C and m_CM of 0.3–1.5?kg?·?h^?1, and also applied mass and energetic balances. LHMP generally exhibited higher mass and energetic losses than the control (milk powder containing lactose), as a consequence of the relatively low dryability of LHMP. For a lab scale spray dryer, the ideal conditions settings for LHMP production were θ_air,in?=?145?±?2°C and m_CM?=?1.0?kg?·?h^?1, taking into account the mass yield and energetic cost (kJ?·?kg^?1 of powder) of the process. These ideal conditions are a potential tool for the industrial development of lactose-free dairy powders.     

Melatonin Positively Regulates Both Dark- and Age-Induced Leaf Senescence by Reducing ROS Accumulation and Modulating Abscisic Acid and Auxin Biosynthesis in Cucumber Plants

Melatonin (MT), as a signaling molecule, plays a vital role in regulating leaf senescence in plants. This study aimed to verify the antioxidant roles of MT in delaying dark- or age-induced leaf senescence of cucumber plants. The results showed that endogenous MT responds to darkness and overexpression of CsASMT, the key gene of MT synthesis, and delays leaf senescence stimulated by darkness, as manifested by significantly lower malonaldehyde (MDA) and reactive oxygen species (ROS) contents as well as higher activities and gene expression of antioxidant enzymes compared to the control. Moreover, MT suppressed both age- or dark-induced leaf senescence of cucumber, as evidenced by a decrease in senescence-related gene SAG20 and cell-death-related gene PDCD expression and ROS content and an increase in antioxidant capacity and chlorophyll biosynthesis compared with the H₂O-treated seedlings. Meanwhile, the suppression of age-induced leaf senescence by melatonin was also reflected by the reduction in abscisic acid (ABA) biosynthesis and signaling pathways as well as the promotion of auxin (IAA) biosynthesis and signaling pathways in cucumber plants in the solar greenhouse. Combining the results of the two separate experiments, we demonstrated that MT acts as a powerful antioxidant to alleviate leaf senescence by activating the antioxidant system and IAA synthesis and signaling while inhibiting ABA synthesis and signaling in cucumber plants.     

Effect of oxygen vacancies on the microstructure and multiferroic behavior of Bi4.25La0.75Fe0.5Co0.5Ti3O15 ceramics

In order to reveal the solid relationship between oxygen vacancies and multiferroic properties, polycrystalline Bi_4.25La_0.75Fe_0.5Co_0.5Ti₃O₁₅ (BLFCT) ceramics were sintered in argon (BLFCT-Ar), air (BLFCT-air) and oxygen (BLFCT-O₂) by conventional solid state reaction, respectively. Their microstructures, ferroelectric, magnetic properties and valence states of magnetic ions were investigated and compared. X-ray diffraction patterns confirmed a single phase crystal structure in all samples. The lattice constants were calculated and the minor variation of the lattice constants is attributed to the different oxygen vacancy concentration. Furthermore, different oxygen vacancy concentration may be responsible for the different values of RT-recorded remanant magnetization (2M_r), remanent polarization (2P_r) as well as magnetic phase transition temperatures (T_CM). The magnetic response of sample sintered in argon (2M_r =0.52 emu/g, T_CM=392 K) is significantly superior to that of the others, while the sample sintered in oxygen exhibits a better remnant polarization (2P_r =11.6 µC/cm²) at an applied electric field of 160 kV/cm. The BLFCT-Ar sample was then annealed in oxygen to further justified the dependence of 2P_r and 2M_r on oxygen vacancies. Finally, outcome of the XPS measurement manifested the ratios of Fe²⁺/Fe³⁺ and Co²⁺/Co³⁺, and reconfirmed the different oxygen vacancy concentration in three samples.     

Tunable structural transition and multiferroic properties of the composite thin films through the structural transition of magnetic layer

The Bi_0.9Er_0.1Fe_0.96Mn_0.02Co_0.02O₃/Co_1-xMn_xFe₂O₄ (BEFMCO/CM_xFO) thin films have been deposited by sol-gel method. Structural distortion is observed in the BEFMCO with the appearance of trigonal-R-3m: H in the CM_xFO. The enhanced multiferroic properties, well electrically writable and ferroelectric switching properties are obtained in BEFMCO/CM_xFO thin films. The investigation indicates that the structural transformation of the CM_xFO influences the structure and multiferroic properties of BEFMCO and the interfacial effects between BEFMCO and CM_xFO layers. This transformation and Mn-doping cause the change of carriers, which solves the problem that the magnetic layer exacerbates the ferroelectric properties. It promotes to form the weak local electric field, which causes the weak interface effect, and brings out the weak resistive switching in the BEFMCO/CM_xFO thin films. Therefore, it is believed that the BEFMCO/CM_xFO films can offer a potentially tunable structural transformation of composite films for practical applications.     

Elastic behavior of concentrated solutions of acrylonitrile copolymers

The elastic behavior of concentrated solution of acrylonitrile copolymer was investigated by the capillary end correction method. The results were as follows. (1) The shear stress is proportional to recoverable shear strain in accordance with Hooke's law below critical concentration; above a critical concentration, however, the shear modulus depends on shear stress. (2) The log–log plots of zero shear modulus against polymer concentration and molecular weight fall on two straight lines with different slopes. The intersection of lines is considered to be the onset of elastically deformable entanglement network. We denote this inflection point as (C_c)_e or (M_c)_e. (3) The log–log plot of viscosity against polymer concentration does not show a change of slope at the critical concentration (C_c)_e. (4) By the application of the kinetic theory of rubberlike elasticity to the pseudo-network structure of concentrated polymer solution, in the range of C_c < C < (C_c)_e or M_c < M < (M_c)_e, the number of chain entanglement per molecule is kept one; moreover, in the range of C > (C_c)_e, or M > (M_c)_e, the number of chain entanglement increases to three.     

Melatonin Enhances Drought Tolerance in Rice Seedlings by Modulating Antioxidant Systems,Osmoregulation, and Corresponding Gene Expression

Rice is the third largest food crop in the world, especially in Asia. Its production in various regions is affected to different degrees by drought stress. Melatonin (MT), a novel growth regulator, plays an essential role in enhancing stress resistance in crops. Nevertheless, the underlying mechanism by which melatonin helps mitigate drought damage in rice remains unclear. Therefore, in the present study, rice seedlings pretreated with melatonin (200 μM) were stressed with drought (water potential of −0.5 MPa). These rice seedlings were subsequently examined for their phenotypes and physiological and molecular properties, including metabolite contents, enzyme activities, and the corresponding gene expression levels. The findings demonstrated that drought stress induced an increase in malondialdehyde (MDA) levels, lipoxygenase (LOX) activity, and reactive oxygen species (ROS, e.g., O₂⁻ and H₂O₂) in rice seedlings. However, the melatonin application significantly reduced LOX activity and the MDA and ROS contents (O₂⁻ production rate and H₂O₂ content), with a decrease of 29.35%, 47.23%, and (45.54% and 49.33%), respectively. It activated the expression of ALM1, OsPOX1, OsCATC, and OsAPX2, which increased the activity of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), respectively. Meanwhile, the melatonin pretreatment enhanced the proline, fructose, and sucrose content by inducing OsP5CS, OsSUS7, and OsSPS1 gene expression levels. Moreover, the melatonin pretreatment considerably up-regulated the expression levels of the melatonin synthesis genes TDC2 and ASMT1 under drought stress by 7-fold and 5-fold, approximately. These improvements were reflected by an increase in the relative water content (RWC) and the root-shoot ratio in the drought-stressed rice seedlings that received a melatonin application. Consequently, melatonin considerably reduced the adverse effects of drought stress on rice seedlings and improved rice’s ability to tolerate drought by primarily boosting endogenous antioxidant enzymes and osmoregulation abilities.     

Copolymerization of N-(4-carboxyphenyl)maleimide with acrylonitrile and the properties of its membrane

N-(4-Carboxyphenyl)maleimide (N-4-CPMI, M₁) was copolymerized with acrylonitrile (AN, M₂) to prepare the copolymer. The monomer reactivity ratios and Alfrey-Price Q, e values were determined as r₁ = 0.56, r₂ = 0.84, Q ₁ = 2.0, Q ₂ = 0.6 and e ₁ = 2.06, e ₂ = 1.2. The membrane of copolymer containing 0.25% CPMI had a good tensile property (67.3 MPa). The 0.75 mole% membrane had an excellent selectivity factor (α = 45.3).     

Transport of Europium through Supported Liquid Membrane Containing Dihexyl-N,N-diethylcarbamoylmethylphosphonate

Abstract

The transport of europium has been studied through a supported liquid membrane (SLM) impregnated with dihexy-N,N-diethylcarbamoylmethylphosphonate (CMP). Europium was effectively extracted from the perchlorate solution into SLM, but was insufficiently stripped to a dilute acid solution. The addition of 1-decanol improved the stripping process, and quantitative transport of europium was achieved. By the combination of two SLM systems consisting of diiso-decylphosphoric acid and CMP, europium was transported from the feed solution (0.1 M HNO₃) through the intermediate solution (1 M HclO₄ + 4 M NaClO₄) to the product solution (0.1 M HNO₃) and effectively concentrated by a factor of about 20.     

Effects of Melatonin on the Proliferation and Apoptosis of Sheep Granulosa Cells under Thermal Stress

The cross-talk between oocyte and somatic cells plays a crucial role in the regulation of follicular development and oocyte maturation. As a result, granulosa cell apoptosis causes follicular atresia. In this study, sheep granulosa cells were cultured under thermal stress to induce apoptosis, and melatonin (MT) was examined to evaluate its potential effects on heat-induced granulosa cell injury. The results demonstrated that the Colony Forming Efficiency (CFE) of granulosa cells was significantly decreased (heat 19.70% ± 1.29% vs. control 26.96% ± 1.81%, p < 0.05) and the apoptosis rate was significantly increased (heat 56.16% ± 13.95%vs. control 22.80% ± 12.16%, p < 0.05) in granulosa cells with thermal stress compared with the control group. Melatonin (10⁻⁷ M) remarkably reduced the negative effects caused by thermal stress in the granulosa cells. This reduction was indicated by the improved CFE and decreased apoptotic rate of these cells. The beneficial effects of melatonin on thermal stressed granulosa cells were not inhibited by its membrane receptor antagonist luzindole. A mechanistic exploration indicated that melatonin (10⁻⁷ M) down-regulated p53 and up-regulated Bcl-2 and LHR gene expression of granulosa cells under thermal stress. This study provides evidence for the molecular mechanisms of the protective effects of melatonin on granulosa cells during thermal stress.     

Functional polyethylene composites prepared via polymerization of ethylene with opal‐immobilized zirconocene complex

An opal‐supported zirconocene complex (OC) was prepared and employed to prepare functional polyethylene composite for the first time through in situ polymerization of ethylene. The formation mechanism of anion relating to opal was explained and the values of anions released from pristine opal and that contained in the as‐fabricated polyethylene composites were detected. The OC exhibited high catalytic activities in ethylene polymerization with methylaluminoxane (MAO) the cocatalyst. In addition to higher viscosity‐average molecular weights (M_η), experimental results also showed that the resulting polyethylene composites possessed improved anion‐releasing capacity in comparison with pristine opal in addition to increased tensile strength, Young's modulus, and onset decomposition temperature (T_onset) relative to neat polyethylene due to highly uniform dispersion of opal in polyethylene matrix. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers