Increase In Ion Concentration Research Articles

Atomic-level insights into the mechanism of saline-regulated montmorillonite (001)-salt droplet interface wetting: A molecular dynamics study

Salinity regulation of the wettability of clay minerals plays an important role in many research fields, but the mechanism influencing the process is not fully understood. Molecular dynamics simulations were used with a NaCl solution and the montmorillonite (Mt) to explore the process by which salinity changes surface wettability. Additionally, the effects of salinity on ionic water cooperation, hydration layer formation, and the hydrogen bond network were analyzed. The results showed that the droplet contact angle increased almost linearly with increasing salt concentration. In an ionic droplet, the oxygen atom of a water molecule moves toward the Na ion and the hydrogen atom moves toward the Cl ion, and the Cl ion has more influence on the droplet structure. There are multiple hydration layers in the droplet, and the ion concentration impacts the hydrogen bond network density more than the water structure density. The main ionic component in the first hydration layer of the ionic droplet is the Cl ion, which changes the direction of the OH bond and leads to a decrease in the hydrogen bond density between the first layer of the water molecule and the hydration layer above, which reduces the adsorption of the Mt. (001) surface charge on the upper water molecule. With an increase in salt ion concentration, the spread range of the first layer of water molecules on the mineral surface is reduced, and ionic hydration results in destruction of the hydrogen bond network of the droplet. Specifically, the connection between hydration layers is weakened, so the adsorption of the upper water on the surface is shielded, leading to an increase in hydrophobicity. This research helps to reveal the mechanism underlying many physical processes or phenomena in nature.

Nickel ions release from orthodontic wires into the oral cavity during orthodontic treatment

The medical literature speaks about the influence of the oral cavity environment on the orthodontic archwires containing nickel (Ni) in their structure, causing corrosion of the archwires with the release of nickel ions into the patient’s oral fluids leading to its ingestion. If the nickel content in the body exceeds certain proportions, it is considered hazardous and can cause negative effects on the patient’s body.Aim. To assess whether the clinical application of round thermoactive nickel-titanium (NiTi) archwires will risk increasing the concentration of (Ni) ions in the patient’s oral fluids within first two months of the orthodontic treatment.Materials and methods. The Research was conducted on 17 patients, aged 14 to 27 years, fixed metallic orthodontic appliances were used for treatment. Using an atomic absorption spectrophotometer, oral fluid Samples were analyzed to determine the preliminary рН. Oral fluid samples were gathered from all participants of the study groups during different periods of time, observation was as follows: Before installation of fixed appliances, immediately after fixing the braces and tying up the thermoactive NiTi archwires, in 7 days, one month and two months after fixation.Results. There were no statistically significant differences in concentration of (Ni) ions in first two months of treatment. However, in (25 %) of samples taken from patients in 1-2 months after the beginning of treatment a small increase in concentration of Ni ions (by 7,5 %) was observed.Conclusions. It is improbable that a thermoactive NiTi archwire has a significant additional Ni load for patients undergoing orthodontic treatment.

Contributing Role of Mitochondrial Energy Metabolism on Platelet Adhesion, Activation and Thrombus Formation under Blood Flow Conditions

Platelets have an active energy metabolism mediated by mitochondria. However, the role of mitochondria in platelet adhesion, activation, and thrombus formation under blood flow conditions remains to be elucidated. Blood specimens were obtained from healthy adult volunteers. The consumption of glucose molecules by platelets was measured after 24 hours. Platelet adhesion, activation, and thrombus formation on collagen fibrils and immobilized von Willebrand factor (VWF) at a wall shear rate of 1,500 s−1 were detected by fluorescence microscopy with an ultrafast laser confocal unit in the presence or absence of mitochondrial functional inhibitors of carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (FCCP), antimycin A, and oligomycin. Consumption of glucose molecules within the first 24 h of 4.21 × 10−15 ± 4.46 x 10−15 (n = 6) increased to 13.82 × 10−15 ± 3.46 x 10−15 (n = 4) in the presence of FCCP, 12.11 × 10−15 ± 2.33 x 10−15 (n = 4) in the presence of antimycin A, and 11.87 × 10−15 ± 3.56 x 10−15 (n = 4) in the presence of oligomycin (p < .05). These mitochondrial functional blockers did not influence both surface area coverage by platelets and the 3-dimensional size of platelet thrombi formed on the collagen fibrils. However, a rapid increase in the intracellular calcium ion concentration ([Ca2+] i ) upon adhering on immobilized VWF decreased significantly from 405.5 ± 86.2 nM in control to 198.0 ± 79.2 nM in the presence of FCCP (p < .005). A similar decrease in the rapid increase in ([Ca2+] i ) was observed in the presence of antimycin A and oligomycin. Mitochondrial function is necessary for platelet activation represented by a rapid increase in [Ca2+] i after platelet adhesion on VWF. However, the influence could not be detected as changes in platelet adhesion or 3-dimensional growth of platelet thrombi on collagen fibrils.

Melatonin Mediates Osteoblast Proliferation Through the STIM1/ORAI1 Pathway.

Based on the positive correlation between bone mineral density and melatonin levels in blood, this study confirmed that melatonin supplementation prevents postmenopausal osteoporosis. We further confirmed that melatonin promotes an increase in intracellular calcium concentrations through the STIM1/ORAI1 pathway, thereby inducing the proliferation of osteoblasts. Introduction: Osteoporosis (OP) is a progressive, systemic bone disease that is one of the main causes of disability and death in elderly female patients. As an amine hormone produced by the human pineal gland, melatonin plays an important role in regulating bone metabolism. This study intends to investigate the relationship between melatonin levels in human blood and bone density and to suggest the efficacy of melatonin in treating osteoporosis by performing in vivo and in vitro experiments. Methods: We used liquid chromatography-tandem mass spectrometry to determine the serum melatonin levels in postmenopausal women with osteoporosis and young women with a normal bone mass. The bone density, BV/TV, Tb.Th, Tb.Sp and other indicators of postmenopausal osteoporosis and mice with a normal bone mass were detected by measuring bone density and micro-CT. The intracellular calcium ion concentration was detected using fluorescence microscopy and a full-wavelength multifunctional microplate reader, and the expression of SOCE-related genes and STIM1/ORAI1 proteins was detected using PCR and WB. Results: This study confirmed that bone density positively correlates with the melatonin level in human blood. In the animal model, melatonin supplementation reverses postmenopausal osteoporosis. We explored the internal mechanism of melatonin treatment of osteoporosis. Melatonin promotes an increase in intracellular calcium ion concentrations through the STIM1/ORAI1 pathway to induce osteoblast proliferation. Conclusions: This study provides an important theoretical basis for the clinical application of melatonin in patients with osteoporosis and helps to optimize the diagnosis and treatment of postmenopausal osteoporosis.

Optimization Analysis to Evaluate the Relationships between Different Ion Concentrations and Prymnesium parvum Growth Rate

The purpose of this study was to evaluate the optimum environmental condition required for reaching the maximum growth rate of P. parvum. Eight ions (Na+, K+, CO32−, HCO3−, Ca2+, Mg2+, Cl−, and SO42−) were divided into two groups with a uniform design of 4 factors and 10 levels. The results showed a rising trend in growth rate with increasing ion concentrations. However, concentrations that exceeded the threshold led to a slowdown in the growth rate. Therefore, adequate supply of ion concentrations promoted growth of P. parvum, whereas excessively abundant or deficient ion concentrations inhibited its growth rate. Specifically, the order of impact of the first four ion factors on the growth rate was Na+ &gt; HCO3− &gt; K+ &gt; CO32−. The growth rate of P. parvum reached the maximum theoretical 0.999 when the concentrations of Na+, K+, CO32−, and HCO3− ions were 397.98, 11.60, 3.37, and 33.31 mg/L, respectively. This theoretical growth maximum was inferred from the experimental results obtained in this study. For other ion factors, SO42− had the most influence on the growth rate of P. parvum, followed by Mg2+, Ca2+, and Cl− ions. The growth rate of P. parvum reached the maximum theoretical value of 0.945 when the concentrations of Ca2+, Mg2+, Cl−, and SO42− ions were 11.52, 32.95, 326.29, and 377.31 mg/L, respectively. The findings presented in this study add to our understanding of the growth conditions of P. parvum and provide a theoretical basis for dealing with the water bloom it produces in order to control and utilize it.

Effect of Native Reservoir State and Oilfield Operations on Clay Mineral Surface Chemistry.

An understanding of clay mineral surface chemistry is becoming critical as deeper levels of control of reservoir rock wettability via fluid–solid interactions are sought. Reservoir rock is composed of many minerals that contact the crude oil and control the wetting state of the rock. Clay minerals are one of the minerals present in reservoir rock, with a high surface area and cation exchange capacity. This is a first-of-its-kind study that presents zeta potential measurements and insights into the surface charge development process of clay minerals (chlorite, illite, kaolinite, and montmorillonite) in a native reservoir environment. Presented in this study as well is the effect of fluid salinity, composition, and oilfield operations on clay mineral surface charge development. Experimental results show that the surface charge of clay minerals is controlled by electrostatic and electrophilic interactions as well as the electrical double layer. Results from this study showed that clay minerals are negatively charged in formation brines as well as in deionized water, except in the case of chlorite, which is positively charged in formation water. In addition, a negative surface charge results from oilfield operations, except for operations at a high alkaline pH range of 10–13. Furthermore, a reduction in the concentrations of Na, Mg, Ca, and bicarbonate ions does not reverse the surface charge of the clay minerals; however, an increase in sulfate ion concentration does. Established in this study as well, is a good correlation between the zeta potential value of the clay minerals and contact angle, as an increase in fluid salinity results in a reduction of the negative charge magnitude and an increase in contact angle from 63 to 102 degree in the case of chlorite. Lastly, findings from this study provide vital information that would enhance the understanding of the role of clay minerals in the improvement of oil recovery.

Electrochemical Deposition of Fe–Co–Ni Samples with Different Co Contents and Characterization of Their Microstructural and Magnetic Properties

In this study, to explore the effect of Co contents on the electroplated Fe–Co–Ni samples, three different Fe–Co33–Ni62, Fe–Co43–Ni53, and Fe–Co61–Ni36 samples were electrochemically grown from Plating Solutions (PSs) containing different amounts of Co ions on indium tin oxide substrates. Compositional analysis showed that an increase in the Co ion concentration in the PS gives rise to an increment in the weight fraction of Co in the sample. In all samples, the co–deposition characteristic was described as anomalous. The samples exhibited a predominant reflection from the (111) plane of the face–centered cubic structure. However, the Fe–Co61–Ni36 sample also had a weak reflection from the (100) plane of the hexagonal close–packed structure of Co. An enhancement in the Co contents caused a strong decrement in the crystallinity, resulting in a decrease in the size of the crystallites. The Fe–Co33–Ni62 sample exhibited a more compact surface structure comprising only cauliflower–like agglomerates, while the Fe–Co43–Ni53 and Fe–Co61–Ni36 samples had a surface structure consisting of both pyramidal particles and cauliflower–like agglomerates. The results also revealed that different Co contents play an important role in the surface roughness parameters. From the magnetic analysis of the samples, it was understood that the Fe–Co61–Ni36 sample has a higher coercive field and magnetic squareness ratio than the Fe–Co43–Ni53 and Fe–Co33–Ni62 samples. The differences observed in the magnetic characteristics of the samples were attributed to the changes revealed in their phase structure and surface roughness parameters. The obtained results are the basis for the fabrication of future magnetic devices.

Effects of Ion Content on the Ion Aggregation Morphology and Glass Transition of Poly(styrene-ran-cinnamic acid) (SCA) Zn-Salt Ionomer

Poly(styrene-ran-cinnamic acid) (SCA) Zn-salt ionomers (SCA‒Zn) bearing increasing contents (0, 0.23, 0.55, 1.3, 3.0, and 5.5 mol%) of Zn2+ ions were successfully synthesized by solution neutralization of the SCA with Zn2+ ions at room temperature. As the ion content of the SCA‒Zn increased from 0 to 5.5 mol%, the size and the aggregation number of the ionic aggregates did not change significantly, because the increase in ion content led to a monotonic increase in the number density of ionic aggregates, while the number of ions participating in the aggregates to form ionic aggregates was essentially fixed. Furthermore, the T g values of the SCA‒Zn increased slowly as the Zn2+ ion content increased, and the linear increase rate with Zn2+ ion content was ∼0.8 °C mol−1, which was quite different from the reported increase rate in the T g values of the matrix phase with Na+ ion content of 3–6 °C mol−1. This appeared to be caused by the steric hindrance effect of the adjacent groups of –COO− ions in the SCA and the long-distance electrostatic attraction. In addition, the degree of ionization of the SCA‒Zn was too low to cause large changes in thermal stability.

Study the effects of dry-wet cycles and cadmium pollution on the mechanical properties and microstructure of red clay

In order to study the effect of cadmium ions on the mechanical properties and micro-structure characteristics of the red clay in Guilin, we have conducted triaxial test and the scanning electron microscope tests to analyze the effects of cadmium ion concentration and the number of dry and wet cycles on the mechanical properties and micro-structure changes of the red clay. The results showed the effects of cadmium ions and dry-wet cycles destroy the structure of red clay. The cohesive force of red clay decreases with the increase of cadmium ion concentration, and the internal friction angle first increases and then decreases. With the rise in the number of dry and wet cycles, the cohesive force of cadmium-contaminated red clay first increases and then decreases, and the angle of internal friction rises gradually. Under the action of different cadmium ion concentrations, the stress-strain curve is strain hardening. With the concentration of cadmium ions increases, the strain hardening becomes more apparent; the peak value reached faster. and the axial strain corresponding to the peak value of the line decreases. With the increase in the number of wet and dry cycles, the volume of cadmium-contaminated red clay shrinks and its compactness increases; it gets the peak shear strength faster during the shearing process, and its peak value becomes larger and larger. The main reason for the phenomenon is that cadmium ions destroy the cementation between the particles. The soil particles are mainly in point contact which loosens the structure of the soil; on the other hand, the thickness of the surface diffusion layer of the clay particles increases through chemical action, The exchange of cations increases the porosity of the soil and weakens its strength. The dry-wet cycle shrinks the volume of the red clay, and the soil particles are mainly in surface contact; as the number of dry-wet cycles increases, the soil particles connection is closer, the soil porosity decreases and the strength increases.

Evaluation of kinetic parameters for oxidation of thioacids by benzimidazolium dichromate: A mechanistic study

In a non-aqueous medium, oxidation kinetics of thioglycolic, thiolactic and thiomalic acids by benzimidazolium dichromate have been studied. In the temperature range of 20°C–50°C, oxidation kinetics were examined by spectrophotometry. In terms of oxidant, the reaction is dependent on the unitary order. In the case of thioacids, we find the Michaelis-Menten type kinetics. Hydrogen-ions act as catalyst in this process. The reaction rate slows down as the Mn2+ ion concentration increases. The reaction does not cause acrylonitrile to polymerize. The formation of a thioester into the pre-equilibrium followed by its progressive degradation was postulated as a mechanism.

Anti-diarrhoeal effect of methanol leaf fraction of Cola hispida Brenan and Keay in rats

Purpose: To evaluate the anti-diarrhoeal activity of 20 % methanol leaf fraction of Cola hispida (MLFC) using castor oil-induced diarrhoea model in rats.&#x0D; Methods: The activity of MLFC against castor oil-induced diarrhoea, intestinal fluid accumulation (enteropooling), and gastrointestinal motility were evaluated. The experimental animals were grouped into five, each with four animals. Group 1 received distilled water, while group 2 received loperamide and served as negative and standard control groups respectively. Groups 3 - 5 were administered 200, 400 and 600 mg/kg of MLFC respectively. One-hour post-treatment, castor oil (p.o.) was used to induce diarrhoea in all the groups. The activity of MLFC was tested against castor oil-induced looseness of stool, fluid accumulation in the intestine and intestinal motility of charcoal meal. Its effect on electrolyte concentration in the small intestinal content was assessed; furthermore, its effect on the electrolyte concentrations of Na+, Cl-, K+, and HCO3- in supernatants obtained from the intestinal loop effluents of the rats was evaluated.&#x0D; Results: The MLFC produced a significant (p &lt; 0.05) and dose-dependent decrease in the severity of diarrhoea and frequency of watery stool passed in castor oil-induced diarrhoea, enteropooling, gastrointestinal transit of charcoal meal in rats and serum concentrations of sodium and chloride ions, while significant (p &lt; 0.05) increase in potassium and bicarbonate ion concentrations were observed when compared with diarrhoeal control group. Similar inhibitory effects were obtained for loperamide control group.&#x0D; Conclusion: The results of the study indicate that methanol leaf fraction of Cola hispida possesses anti-diarrhoeal properties by inhibiting intestinal peristalsis and hypersecretion of water and electrolytes. Thus, the findings lend some support to the traditional use of the plant for the treatment of diarrhoea.

Anti-diarrhoeal effect of methanol leaf fraction of Cola hispida Brenan and Keay in rats

Purpose: To evaluate the anti-diarrhoeal activity of 20 % methanol leaf fraction of Cola hispida (MLFC) using castor oil-induced diarrhoea model in rats.&#x0D; Methods: The activity of MLFC against castor oil-induced diarrhoea, intestinal fluid accumulation (enteropooling), and gastrointestinal motility were evaluated. The experimental animals were grouped into five, each with four animals. Group 1 received distilled water, while group 2 received loperamide and served as negative and standard control groups respectively. Groups 3 - 5 were administered 200, 400 and 600 mg/kg of MLFC respectively. One-hour post-treatment, castor oil (p.o.) was used to induce diarrhoea in all the groups. The activity of MLFC was tested against castor oil-induced looseness of stool, fluid accumulation in the intestine and intestinal motility of charcoal meal. Its effect on electrolyte concentration in the small intestinal content was assessed; furthermore, its effect on the electrolyte concentrations of Na+, Cl-, K+, and HCO3- in supernatants obtained from the intestinal loop effluents of the rats was evaluated.&#x0D; Results: The MLFC produced a significant (p &lt; 0.05) and dose-dependent decrease in the severity of diarrhoea and frequency of watery stool passed in castor oil-induced diarrhoea, enteropooling, gastrointestinal transit of charcoal meal in rats and serum concentrations of sodium and chloride ions, while significant (p &lt; 0.05) increase in potassium and bicarbonate ion concentrations were observed when compared with diarrhoeal control group. Similar inhibitory effects were obtained for loperamide control group.&#x0D; Conclusion: The results of the study indicate that methanol leaf fraction of Cola hispida possesses anti-diarrhoeal properties by inhibiting intestinal peristalsis and hypersecretion of water and electrolytes. Thus, the findings lend some support to the traditional use of the plant for the treatment of diarrhoea.

Synthesis of ultrasonic assisted co-precipitated Ag/ZnO nanorods and their profound anti-liver cancer and antibacterial properties

The current cancer Survey reports liver cancer is the second leading cause of cancer related death worldwide. Active liver cancer research is underway as several new therapies are emerging to treat it, with more showing promise. Our present study aims at preparation of silver/zinc oxide nanocomposites for potential applications in antibacterial, anti-inflammatory, anti-cancerous, against human liver cancer cells (hepG2). Silver ions added Zinc oxide (Ag/ZnO) have been synthesized by ultrasonic assisted co-precipitation method. It is found that 3% of silver ions added ZnO were precipitated as nanoplates. And interestingly the observation shows when the concentration of the silver ions increased to 5%, it reduced as nanorods. X-Ray diffraction, SAED patterns and Fourier Transform Infrared Spectrum confirms that silver ions are well attached in ZnO lattice. Ag/ZnO possesses good absorption in the UV region. The reduction in average particle size due to the increase of silver ion concentration in ZnO lattice was confirmed by dynamic light scattering (DLS).SEM and TEM studies witnessed the micro structural transformation from nanoplates (3% Ag) to the rod-like structure on (5% Ag).Ag/ZnO displayed strong antibacterial activity against different pathogens. The obtained results are comparable with standard antibiotics against pathogenic bacteria. Anti-inflammatory study reveals that Ag/ZnO prevents inflammation. Dose dependent response of Ag/ZnO against human liver cancer cells (HepG2) indicates its greater efficacy in killing cancer cells. The selective silver ion concentration (5%) in ZnO have reduced its cross-sectional area with respect to volume. This property helps the silver ion/ZnO nanorods to penetrate efficiently into the affected cells and fight against bacteria, suppress cell inflammation, eradicate the growth of liver cancer cells; which shows feasibility of this composites in further research for therapeutic applications.

The physical and photocatalytic properties of thallium doped cobalt ferrites for efficient hydrogen fuel production

Herein, a series of CoFe2-xTlxO4 (0.03 ≤ x ≤ 0.15) nanoceramics were prepared via a meso-2,3-dimercaptosuccinic acid assisted solvothermal route. The influence of a thallium ion dopant on the structural, magnetoptical, electrical, and photocatalytic characteristics has been scrutinized. The X-ray diffraction demonstrated that CoFe2-xTlxO4 nanoceramics have a cubic structure at all Tl ions concentrations. The Raman scattering spectroscopy revealed the reshuffling of the iron cation between the tetrahedral and octahedral sites of the structure of ferrite due to the substitution with Tl ions. The magnetic properties showed an increase of the saturation magnetization from 59.5 emu/g to 67.4 emu/g and an increase of the coercive field from 344.2 Gauss to 583.1 Gauss with increasing the amount of Tl cations. The optical band gap decreases with the increase of Tl ion concentration. The activation energy decreases from 0.44 eV to 0.26 eV with increasing the Tl ion concentration. These unique physical properties gave rise to the outstanding capability of the as-synthesized CoFe2-xTlxO4 nanoceramics for the photocatalytic production of hydrogen fuel.

Sanguinarine induces apoptosis in Eimeria tenella sporozoites via the generation of reactive oxygen species

Eimeria tenella (E. tenella) is the most pathogenic genus in Eimeria and can lead to a huge number of deaths of chickens, causing significant economic losses in the poultry industry worldwide. As a natural alkaloid, sanguinarine has many medicinal effects; to a certain extent, it can replace antibiotics and has good application prospects in veterinary medicine. To evaluate the effect of sanguinarine on sporozoites of E.tenella, we used flow cytometry and immunofluorescence staining to detect reactive oxygen species (ROS), mitochondrial membrane potential (MMP), calcium ion (Ca2+), and caspase-3 activation in E.tenella sporozoites treated with different concentrations of sanguinarine. The results of flow cytometry showed that sanguinarine could inhibit the invasion of sporozoites of E.tenella in vitro (P < 0.05) and increase the reactive oxygen species and calcium ions in the sporozoites (P < 0.05). The results of immunofluorescence staining showed that sanguinarine could decrease the mitochondrial membrane potential of sporozoites. Our analysis suggests that sanguinarine can induce apoptosis of E. tenella sporozoites through reactive oxygen species-mediated reduction of the mitochondrial membrane potential and an increase in calcium ion concentration. It follows that sanguinarine is likely to be a novel type of anticoccidiosis drug with good research and clinical application prospects.

3D gel-printed porous magnesium scaffold coated with dibasic calcium phosphate dihydrate for bone repair in vivo.

Background/Objective: The treatment of bone defect has always been a difficult problem in orthopedic clinic. The search for alternative biodegradable implants is a hot topic. The development of biodegradable magnesium scaffolds for the treatment of bone defects has long been a goal of the public.MethodsIn this study, we proposed a porous magnesium scaffold prepared by 3D gel printing and surface modification with an additional calcium phosphate coating and use of its strength, degradability and slow degradation rate in a bone graft substitute material. The porous magnesium granular scaffold was prepared by 3D gel printing technology and modified by DCPD (Dibasic Calcium Phosphate Dihydrate) coating. The biocompatibility, degradation rate, and osteogenic ability of the scaffold were evaluated in vitro and in vivo.ResultsThe biocompatibility, in vivo degradation and bone defect healing response of the implants were investigated. Porous magnesium scaffolds were successfully prepared, and the strength of sintered scaffolds reached 5.38 ​MPa. The degradation rates of scaffolds were significantly reduced after coating with DCPD. The cell compatibility evaluation showed that DCPD-coated Mg scaffold was suitable for cell proliferation. In vivo biosafety monitoring showed that scaffold implantation did not cause an increase in Mg ion concentration in vivo, and no toxic damage was detected in the liver or kidney. Micro-CT and pathological results showed that a large amount of new bone was formed at 6 weeks. At 12 weeks, approximately 52% of the scaffold volume remained. At 24 weeks, osteogenesis, which was stimulated by some residual scaffold, still can be observed. In summary, this study suggests that 3D gel-printed DCPD-coated porous magnesium scaffolds have great potential as bone graft alternatives.ConclusionIn summary, this study suggests that 3D gel-printed DCPD-coated porous magnesium scaffolds have great potential as bone graft alternatives.The Translational potential of this articleThe translational potential of this article is to make use of the advantages of 3D gel printing technology with higher efficiency and lower cost compared with SLM and SLS technologies, and use pure magnesium powder as raw material to prepare degradable porous magnesium metal scaffolds, opening up a new technical route for the preparation of degradable porous magnesium scaffolds which are made for bone defect regeneration in the future.

Production of Cr3+ substituted Li–Zn nanocrystalline ferrite by citrate method: Studies on structure, cation occupancy, elastic, optical and magnetic performance

The structural, elastic, optical and magnetic characteristics of Li0.4Zn0.2CrxFe2.4-xO4 (0.0 ≤ x ≤ 0.5; step 0.1) produced using a citrate precursor were studied. X-ray powder diffraction data indicate that all of the generated samples are single-phase spinel structures with no additional phases. The lattice parameter reduces from 8.355 Å to 8.333 Å when the chromium content rises. The crystallite sizes of the compositions were assessed by Scherrer's and Williamson-Hall (W–H) approaches. Infrared (IR) spectroscopy revealed two significant absorption bands generated by vibrations at the tetrahedral and octahedral sites. The elastic moduli (bulk modulus ‘B’, rigidity modulus ‘G’ and Young's modulus ‘E’) as well as the Debye temperature (θD) assessed by IR spectroscopy rise as the Cr3+ ions concentration increases. Chromium addition inhibits grain growth and enhances the mechanical strength of Li–Zn nanoferrites. Diffuse reflectance spectra (DRS) were utilized to evaluate the optical band gap (Eg) of Li–Zn–Cr nanoferrite, which was found to drop from 1.96 to 1.84 eV. The vibrating sample magnetometer (VSM) was used to perform the magnetic analysis, and various magnetic parameters were derived using the M − H curves results. Acceptable values of saturation magnetization (78.6–44.05 emu/g) and coercivity (30.87–44.65 G) were found in this system, making these nanoferrites ideal for high-density recording medium and electromagnets applications. Based on the experimental results of lattice parameters, and magnetization, a quite reasonable cation distribution was postulated for all samples. Theoretically predicted lattice parameters and magnetic moments derived from the suggested cation distribution agree with those determined empirically from XRD and VSM results, respectively. The switching field distribution curves were schemed utilizing the first derivative of magnetization data from M − H loops. The Curie temperature decreases significantly with Cr3+ substitution.

Ion Sensitivity of Hygroscopic Insulator Field Effect Transistors

Given the many and varied roles of ions in living organisms, biocompatible organic ion sensors are a matter of considerable interest. In this work, simple, low-voltage, solid-state hygroscopic insulator field effect transistors (HIFETs) have been tested to characterise their ion-sensitive properties. Two biologically relevant salt solutions, sodium chloride (NaCl) and potassium chloride (KCl), were tested. To assess pH sensitivity, solutions of hydrochloric acid (HCl) and sodium hydroxide (NaOH) were also tested. The salts and acidic solutions caused similar, concentration-dependent changes in HIFET performance from 10 mM to 1 M, consistent with an increase in ion concentration in the hygroscopic insulator, increasing device capacitance. By contrast, basic solutions caused an overall decrease in device performance, consistent with a net removal of ions due to acid-base reactions between the insulator and the analyte. These results show that HIFETs exhibit promising sensitivity to a range of ions, and can therefore serve as platforms for future ion-selective devices.

Effect of Copper Nanoparticles and Ions on Epididymis and Spermatozoa Viability of Chinese Soft-Shelled Turtles Pelodiscus sinensis

Copper nanoparticles (CuNPs) have been widely used in various industrial and commercial applications, which become a potential threat to aquatic organisms. Nevertheless, their potential toxicity to the epididymis and sperm remains little known. In this study, we evaluated the effect of CuNPs and copper ions (CuSO4) on the spermatozoa viability, epididymal structure, antioxidant enzyme activity, and inflammatory cytokines in cauda epididymis of the Chinese soft-shelled turtle. Results showed that the spermatozoa viability of Chinese soft-shelled turtles decreased significantly with an increase in CuNPs or Cu ions concentrations. The epithelial cells of the epididymal duct of the Chinese soft-shelled turtles with the treatment of 5 mg kg−1 CuNPs were slightly swollen, and the connective tissue between the epididymal ducts was loose. The epithelial structure of the epididymal tube was severely damaged with an increase in Cu ion concentrations. Compared to the control, the antioxidative enzymes activities and the expression of IL-1β, TNF-α, and IL-6 mRNA in the epididymis significantly increased with the treatment of CuNPs or CuSO4. The present study revealed that Cu ions exert more harmful effect on the epididymis and spermatozoa viability of Chinese soft-shelled turtles than copper nanoparticles.

Double-layer structure of the Pt(111)–aqueous electrolyte interface

We present detailed measurements of the double-layer capacitance of the Pt(111)-electrolyte interface close to the potential of zero charge (PZC) in the presence of several different electrolytes consisting of anions and cations that are considered to be nonspecifically adsorbed. For low electrolyte concentrations, we show strong deviations from traditional Gouy-Chapman-Stern (GCS) behavior that appear to be independent of the nature of the electrolyte ions. Focusing on the capacitance further away from PZC and the trends for increasing ion concentration, we observe ion-specific capacitance effects that appear to be related to the size or hydration strength of the ions. We formulate a model for the structure of the electric double layer of the Pt(111)-electrolyte interface that goes significantly beyond the GCS theory. By combining two existing models, namely, one capturing the water reorganization on Pt close to the PZC and one accounting for an attractive ion-surface interaction not included in the GCS model, we can reproduce and interpret the main features the experimental capacitance of the Pt(111)-electrolyte interface. The model suggests a picture of the double layer with an increased ion concentration close to the interface as a consequence of a weak attractive ion-surface interaction, and a changing polarizability of the Pt(111)-water interface due to the potential-dependent water adsorption and orientation.