Electrical Resistivity Values Research Articles

Electrical properties of the base film heterosystem Al/ITO/polyimide/Al2O3 for capacitive converter

On the basis of the conducted structural studies of thin films, a structural and technological solution was developed and a thin film capacitive transducer was created for acoustic monitoring of metal products by a capacitive method. It was determined that along with the crystalline structure of the layers, it is also necessary to control the surface electrical resistance of the conductive ITO layer, the values of which determine the possibility of using such a structure as a coating of a capacitive converter without significant losses of the useful signal, and the dielectric permeability of the Al2O3 layer, which significantly affects the value of the useful signal With the help of the four-probe method, it was established that the surface electrical resistance (R□) of ITO layers under optimal deposition conditions is equal to 8–15 Ohm/□. The study of electric power Hall results indicate that the obtained value of specific electrical resistance is determined by the concentration of the main charge carriers from about 8.3·1020 cm–3 and the mobility of the main charge carriers at the level of 44 cm2/(V·s). The results of studies of dielectric properties indicate an increase in the value of the dielectric constant of the polyimide/Al2O3 structure, which is 8.5–11.5 relative to units, relative to the polyimide film (3–3.9 relative units) by approximately 3 times at frequencies of the exciting signal in the range of 10 Hz–10 MHz. This fact confirms the assumption about the possibility of increasing the dielectric constant of the interlayer due to the application of a thin layer of Al2O3 on the polyimide film. To confirm the possibility of increasing the sensitivity of the method due to the use of a capacitive transducer based on the Al/ITO/polyimide/Al2O3 structure, in comparison with classical transducers, a series of aluminium samples was studied at an oscillation frequency of 2.5 MHz. The value of the received signal when using a thin-film converter increases by 7.6 times compared to a classic converter, which correlates well with the measurements of dielectric permeability of dielectric layers and taking into account the decrease in the thickness of the dielectric layer. Thus, the increase in the sensitivity of the capacitive method in the case of using thin-film capacitive converters based on the Al/ITO/polyimide/Al2O3 structure is experimentally confirmed. The maximum amplitude of the acoustic displacement occurs at the edge of the plate, so studies were conducted on electrodes with cutouts, which made it possible to increase the acoustic signal twice for a large internal cutout.

Синтез токопроводящих серебряных чернил с низкой температурой спекания для применения в струйной печати

Transparent silver ink based on silver amino complex for inkjet printing has been developed. 1,2-diaminopropane, which acts as a solvent and complexing agent, significantly lowered the decomposition temperature of the silver salt and ensured the chemical stability of the resulting ink at room temperature. The annealed films were characterized by close packing and low electrical resistance values (8.5 μOhm·cm at an annealing temperature of 150°C). The ink provides productive inkjet printing while maintaining stable operation of the print head nozzles.

Vibration control of flexible rotors using a passive magnetic device working on the principle of electromagnetic shunt damping

Excessive rotor vibration can propagate the micro-cracks and hence the premature failure of the rotor system. A passive magnetic device working on the principle of electromagnetic shunt damping (EMSD) is proposed to passively control the rotor vibrations. Although, these EMSD-based damping systems are quite common in the literature, however, there is not even a single article available in the literature, showing the application of such a device passively controlling the rotor vibrations from a distance. Due to the flow of flux between the rotor, stator, and air gap, the modeling procedure for such an EMSD-based system changes completely and is not available in the literature. Due to rotor movement, there is a variation in the magnetic flux provided by the permanent magnets placed in the device. Due to electromagnetic interactions, electric currents are induced in the windings provided in the device. When these currents are allowed to pass through electrical resistance, damping forces are generated. In this way, vibration energy is converted into heat energy. In this research, it is observed that the damping effect is maximum for an optimal value of electrical resistance. The effect of several turns in the windings and permanent magnet thickness is also investigated in terms of the production of damping forces. The efficiency of the device is mathematically proved through simulations. Further, experimental results verify the effectiveness of the proposed device.

DETERMINATION OF INTERVALS REGARDING POSSIBLE VALUES OF CHARGE PARAMETERS WHEN PRODUCING FERROALLOYS

The energy performance of the ore-thermal furnace is affected by the electrical and thermal parameters of the charge, which vary depending on its composition and heating temperature. Namely: specific electrical resistance (SER), mass heat capacity, specific density and coefficient of thermal conductivity. Many scientists experimentally established the mathematical dependence of these parameters on temperature. However, in order to ensure the adequacy of the complex model of the ore-thermal furnace in the mode of its adjustment for a specific process, it is necessary to determine the intervals of possible values of the specified parameters of the charge loaded into it. In the future, the optimization problem considers all possible combinations of their discrete values within the previously mentioned limits, and the one of them that provides the minimum prediction error of the model is determined. If we consider the charge as a whole, then the intervals of the value of the specific electrical resistance depending on the temperature range from 2.055 to 9.249 Ohm·m at low temperatures and from 0.002 to 0.018 Ohm·m in the range of 1200-13000С, depending on the percentage composition of its components. The largest fluctuations in the thermal conductivity values of the charge are present in the temperature range from 500 оС to 900 оС and are 0.754—1.93 W/m·оС. The largest fluctuations in the heat capacity values of the charge are characteristic of high temperatures. Among other input parameters of the complex model of the operation of the ore-thermal furnace, there is also the bulk density of the charge, which also has its fluctuation limits, but only the limits of its components are known. The formula for calculating the density of the charge as a whole is proposed and its maximum and minimum values are established. The obtained information is sufficient to carry out more accurate technological calculations regarding the specified properties at different temperatures and components of the charge from which certain grades of ferroalloys are smelted. Therefore, in order to set an optimization problem regarding the minimization of the possible forecast error of the proposed model, it is possible to determine their specific oscillation intervals. In the further selection of the parameter values, they will be used as input data in the complex mathematical model of the ore-thermal furnace operation, which makes it possible to dynamically monitor the electrical and thermal processes that are directly related to each other and occur during the smelting of ferroalloys.

Protective effects of Bifidobacterium bifidum FL-228.1 on dextran sulfate sodium-induced intestinal damage in mice.

Numerous studies have found that probiotics benefit the intestinal barrier. However, the prophylactic effects of probiotics on the intestinal barrier, i.e., if probiotics exert protective effects in healthy individuals to defend them against harmful elements, have seldomly been reported. The present study aimed to investigate the possible mechanisms of potential strains with the function of preventing intestinal barrier damage. This study investigated nine potential probiotic strains using in vitro and in vivo models on their intestinal barrier-protecting properties. Transcriptomic was then employed to decipher the underlying mechanisms of action of the strains. The results showed that the strains, to varying degrees, regulated the ratio of interleukin (IL)-10 and IL-12 in peripheral blood mononuclear cells (PBMCs), increased the transepithelial electrical resistance (TEER) values, and decreased Caco-2 cell monolayers permeability. Correspondingly, the strains showed different prophylactic efficacies in protecting mice from dextran sulfate sodium (DSS)-induced intestinal barrier damage. Remarkably, Bifidobacterium bifidum FL-228.1 (FL-228.1) showed the best prophylactic efficacies in protecting mice from DSS-induced intestinal barrier damage. Further research suggested that FL-228.1 exerted its prophylactic effects by enhancing mucin 2 (Muc2) production and Claudin (Cldn)-4 in the colon. Furthermore, the transcriptomic and protein-protein interactions (PPI) analyses indicated that the inhibition of NLRP3 and the activation of PPARγ and TLR2 could be involved in protecting the intestinal barrier by FL-228.1. Bifidobacterium bifidum FL-228.1 may be developed as a promising probiotic for the prevention of intestinal barrier damage via PPARγ/NLRP3/ TLR2 pathways by enhancing Muc2 and Cldn-4.

Gold Leaf-Based Microfluidic Platform for Detection of Essential Oils Using Impedance Spectroscopy.

Drug delivery systems are engineered platforms for the controlled release of various therapeutic agents. This paper presents a conductive gold leaf-based microfluidic platform fabricated using xurography technique for its potential implication in controlled drug delivery operations. To demonstrate this, peppermint and eucalyptus essential oils (EOs) were selected as target fluids, which are best known for their medicinal properties in the field of dentistry. The work takes advantage of the high conductivity of the gold leaf, and thus, the response characteristics of the microfluidic chip are studied using electrochemical impedance spectroscopy (EIS) upon injecting EOs into its micro-channels. The effect of the exposure time of the chip to different concentrations (1% and 5%) of EOs was analyzed, and change in electrical resistance was measured at different time intervals of 0 h (the time of injection), 22 h, and 46 h. It was observed that our fabricated device demonstrated higher values of electrical resistance when exposed to EOs for longer times. Moreover, eucalyptus oil had stronger degradable effects on the chip, which resulted in higher electrical resistance than that of peppermint. 1% and 5% of Eucalyptus oil showed an electrical resistance of 1.79 kΩ and 1.45 kΩ at 10 kHz, while 1% and 5% of peppermint oil showed 1.26 kΩ and 1.07 kΩ of electrical resistance at 10 kHz respectively. The findings obtained in this paper are beneficial for designing suitable microfluidic devices to expand their applications for various biomedical purposes.

Application of Resistivity and Seismic Refraction Tomography for Landslide Stability Assessment in Vallcebre, Spanish Pyrenees

Geophysical surveys are a noninvasive reliable tool to improve geological models without requiring extensive in situ borehole campaigns. The usage of seismic refraction tomography (SRT), electrical resistivity tomography (ERT) and borehole data for calibrating is very appropriate to define landslide body geometries; however, it is still only used occasionally. We present here the case of a Spanish Pyrenees slow-moving landslide, where ERT, SRT and lithological log data were integrated to obtain a geological three-dimensional model. The high contrasts of P-wave velocity and electrical resistivity values of the upper materials (colluvial debris and clayey siltstone) provided accurate information on the geometry of the materials involved in the landslide body, as well as the sliding surface. Geophysical prospecting allowed us to identify the critical sliding surface over a large area and at a reduced cost and, therefore, gives the geophysical method an advantage over borehole data. The three-dimensional model was used to carry out stability analyses of a landslide in 2D and 3D, which, coherently with previous studies, reveal that the lower part is more unstable than the upper units.

Composite Based on Multi-Walled Carbon Nanotubes and Manganese Oxide with Rhenium Additive for Supercapacitors: Structural and Electrochemical Studies

The structure and electrochemical characteristics of composites based on multi-walled carbon nanotubes (MWCNTs) and manganese oxide with the addition of rhenium oxide has been studied. It has shown that the decorating of the MWCNT surface with layers or nanoparticles of manganese oxide (Mn(III) + Mn(IV)) provides more than a twofold increase in the value of the specific capacitance at low potential scan rates. However, composites based only on manganese oxide exhibit poor electrochemical behavior and the value of the specific capacitance decreases rapidly with increasing potential scan rate due to the limitation of diffusion processes. The addition of rhenium oxide to composites significantly increases their electrochemical properties due to changes in the chemical composition and morphology of composites. Studies of the structure and chemical state have shown that an improvement in the specific capacitance is provided by increasing in the proportion of Mn(IV) oxide in such composites, which has the ability to rapidly and completely reverse redox reactions and has lower electrical resistance values, compared to Mn(III) oxide. A detailed analysis of the voltammetric data showed that an increase in the rate capability in composites with the addition of rhenium oxide can also be provided by increasing the availability of the electrode surface for electrolyte ions and increasing the amount of charge stored due to the formation of a double electric layer.

Fabrication and Performance Analysis of AZO and MCCO as Thin Film-Thermoelectric Generator Materials

The purpose of this research was to determine the performance of AZO and MCCO materials as constituents of the thin film-thermoelectric generator module. The method used for fabrication is DC Magnetron Sputtering. The electrode material used is Ag and the substrate used is SiO2 glass. The arrangement of the thin film used for the fabrication of the thermoelectric module is P-N-P-N-P-N-P-N-P-N (5 couples of p-n junctions). Based on the test results, the thickness of the thin film type N is 74.72 nm and type P is 90.34 nm. At the highest test temperature (300 oC), the AZO Seebeck coefficient value is -108 µV/K while the MCCO Seebeck coefficient value is 350 µV/K, and the AZO electrical resistivity value is 0.07 Ω.m while the MCCO electrical resistivity value is 0.36 Ω.m. The highest temperature difference given in the test of the AZO and MCCO thin film thermoelectric module is 1.538 °C and the thermoelectric module can produce a voltage of 1,842 ± 0.047 mV, a Seebeck coefficient of 4 µV/K, and an efficiency of 0.44%. Based on this research, it can be concluded that the performance of AZO and MCCO thin film-thermoelectric modules will have better performance at temperatures around 300 - 350 °C.

Study of Electrical and Magnetic Properties of Zn-Co-Ferrite Nanocomposites

The ferromagnetic material exhibits better magnetic properties as compared to other magnetic materials. Cobalt and ferrites have superior soft magnetic properties such as high permeability and magnetic susceptibility. A nanocomposite is prepared using Zinc, Cobalt and Ferrite by combustion synthesis method and the composition is Fe0.5Co0.25Zn0.25. The morphological properties are studied using FESEM images and XRD. The electrical and magnetic properties are studied from 10 Hz to 8 MHz frequency range using LCR meter at ambient temperature. The results show that with increase in frequency, the resistivity as well as permeability decreases. The values of electrical resistivity and dielectric constant suggest the suitability of the nanocomposites in power electronics devices.

Influence of permeability enhancers on the paracellular permeability of metformin hydrochloride and furosemide across Caco-2 cells.

Permeability enhancers can affect absorption of paracellularly transported drugs. This study aims to evaluate effects of permeability enhancers (chitosan, methyl-β -cyclodextrin, sodium caprate, sodium lauryl sulfate, etc.) on the permeability of paracellularly absorbed furosemide and metformin hydrochloride. Methyl thiazole tetrazolium bromide test was carried out to determine the drug concentrations in permeability study. Trans-epithelial electrical resistance (TEER) values determined to assess the integrity of tight junctions. Permeability enhancers were applied at different concentrations alone, in dual/triple combinations. Permeability was determined using human colorectal adenocarcinoma (Caco-2) cells (TEER>400Ω·cm2). Permeability enhancers have no significant effect (<2-fold; p>0.05) on the permeability of furosemide (1.80×10-5±4.55×10-7cm/s); however, metformin permeability (1.36×10-5±1.25×10-6cm/s) increased significantly (p<0.05) with 0.3% and 0.5% (w/v) chitosan (2.0- and 2.7-fold, respectively), 1% methyl-β -cyclodextrin (w/v) (3.5-fold), 10 and 20µmol/L sodium caprate (2.2- and 2.8-fold, respectively), and 0.012% sodium lauryl sulfate (w/v) (1.9-fold). Furosemide permeability increased significantly (p<0.05) with chitosan-sodium lauryl sulfate combination (1.7-fold), and all triple combinations (1.4- to 1.9-fold). Chitosan containing dual/triple combinations resulted in significant increase (p<0.05) in metformin permeability (1.7 to 2.8-fold). All results indicated that absorption of furosemide and metformin can be improved by the combination of permeability enhancers. Therefore, it can be evaluated for the formulation of development strategies containing furosemide and metformin by the pharmaceutical industry.

Effect of plastic deformation on the phase composition and electromagnetic characteristics of the 321N austenitic steel (08Kh18N10T)

The changes in the phase composition and electromagnetic properties of the 321N chromium-nickel austenitic steel under plastic deformation by uniaxial tension are studied. As strain increases from 0 to 0.37, the content of ferromagnetic α′-martensite in the steel increases monotonically to 60%. The electrical resistivity and the initial magnetic permeability increase monotonically by factors of 1,25 and 18, respectively. To monitor the strain state and the content of α'-martensite in products made of the 321N steel, it is preferable to use initial magnetic permeability rather than electrical resistance. The skin layer thickness of the deformed 321N steel for frequencies from 5 to 1000 kHz is calculated from the experimental values of initial magnetic permeability and electrical resistivity. Eddy current diagnostics of the state of the surface of products made of this steel, hardened by surface plastic deformation, is proposed to be performed at frequencies ranging between 100 and 200 kHz.

Engineering of Optical and Electrical Properties of Electrodeposited Highly Doped Al:ZnO and In:ZnO for Cost-Effective Photovoltaic Device Technology.

Resistivity and transparency of zinc-oxide layers (ZnO) for chalcopyrite photovoltaic technology applications were engineered by activation of the Burstein-Moss (BM) effect at high concentrations of aluminium (Al) and indium (In) dopant. The Al:ZnO and In:ZnO layers were processed by cost-effective, large-area, fast-rate electrochemical deposition techniques from aqueous solution of zinc nitrate (Zn(NO3)2) and dopant trichlorides, at negative electrochemical potential of EC = (-0.8)-(-1.2) V, moderate temperature of 80 °C, and solute dopant concentrations of AlCl3 and InCl3 up to 20 and 15 mM, respectively. Both Al:ZnO and In:ZnO layers were deposited on Mo/glass substrates with ZnO and ZnO/ZnSe buffers (Al:ZnO/ZnO/Mo/glass, In:ZnO/ZnO/ZnSe/Mo/glass), respectively. Based on the band-gap energy broadening of Al:ZnO and In:ZnO originated by the BM effect, maximum carrier concentrations of the order 1020 and 1021 cm-3, respectively, were determined by optical characterization techniques. The (electrical) resistivity values of Al:ZnO calculated from optical measurements were commensurate with the results of electrical measurements (10-4 Ohm·cm). In both cases (Al:ZnO and In:ZnO), calibration of carrier density in dependence of solute dopant concentration (AlCl3 and InCl3) was accomplished. The p-n junctions of Au/In:ZnO/ZnO/ZnSe/CIGS/Mo on glass substrate exhibited current-voltage (I-V) characteristics competing with those of crystalline silicon (c-Si) solar cells.

Wildfire Effects on Cryosols in Central Yakutia Region, Russia

Forest fires are one of the most significant types of disturbance on a global scale, affecting biodiversity and biogeochemical cycles and playing an important role in atmospheric chemistry and the global carbon cycle. According to a remote monitoring information system, forest fires in Yakutia were the largest wildfires in the world in 2021. In this regard, mature pale-yellow soils unaffected by fire were investigated in comparison with the same soils that were strongly affected by surface fire in 2021 in the area surrounding Yakutsk, Yakutia region. Data obtained showed an intensive morphological transformation of the topsoil layers, increase of total organic matter and slight increase of pH, and apparent decrease of basal respiration and content of microbial biomass. A slight accumulation of Zn and Ni in soils due to wildfires was recorded, as well as alteration in the distributions of heavy metals in the soil profile. Moreover, an electric resistivity study was carried out during field studies. An influence of forest fire on the electrical resistivity value was not reliably found, but the vertical electrical resistivity sounding provided precise data regarding the degree of soil-permafrost layer homogeneity and/or heterogeneity.

Epitaxial electrodeposition of Cu2O on Ag substrates in sulfate baths

A series of Cu2O samples were electrodeposited on polycrystalline Ag substrates in an electrolyte containing 0.4 M cupric sulfate and 1.3 M lactic acid at different electrolyte temperatures, pH values, and current densities. The electron backscatter diffraction technique was used to characterize the epitaxial orientation relationship (OR) between the deposited Cu2O films and underlying Ag grains. Epitaxial growth was mostly prohibited for the films deposited at pH 9 and 25 °C, whereas epilayers consisting of crystals of a single orientation were deposited on most of the substrate grains at conditions of pH 12/25 °C, pH 9/60 °C, and pH 12/60 °C. In addition to the expected cube-on-cube OR, four more ORs were identified. The existence of multiple ORs was probably a result of coincidence site lattice matching. The adoption of the epitaxial OR for Cu2O films strongly depended on the orientations of the substrate grains. Finally, transmission electron microscopy analysis indicated that the epilayer deposited at 60 °C contained a relatively low density of threading dislocations on the order of 109 cm−2 and thus exhibited low electrical resistivity values of 1–3 × 103 Ω·cm.

Persentase keberhasilan inseminasi buatan dosis ganda pada sapi persilangan Limousin dengan karakter lendir serviks yang berbeda

Objective: The aim of the study was to find out the successful pregnancy in Limousin crossbreed cattle using double-dose AI method on different characters of cervical mucus. Methods: The material used in this study were 45 female cattle with BCS criteria 3-6 on a scale of 1-9 and aged 1.8-6 years. The parameters observed were the condition of the mucus, the pH of the mucus and the electrical resistance of the mucus. AI method uses a double dose method with 4+ semen deposition (cornua utery). Results : The results showed that the highest percentages of NRR 1 and NRR 2 were shown by cattle with the criteria for mucus conditions being present and abundant. It has a pH value of 8 and an electric current resistance is in the range of 20-29 Ω with a percentage of NRR 1 of 62.22%, 53.33% and 71.11%, while the NRR 2 has a percentage of respectively 60.00%, 51.11% and 68.89%. The highest percentage of CR was also shown by cattle with the mucus character, which had percentages of 33.33%, 33.33% and 42.22%, respectively. Conclusions: It was concluded that the highest percentage of pregnancy was shown by cattle with the criteria of mucus being present and abundant, having a pH value of 8 and having an electric current resistance value in the 20-29 Ω category.

Tannic acid attenuates intestinal oxidative damage by improving antioxidant capacity and intestinal barrier in weaned piglets and IPEC-J2 cells.

Tannic acid (TA) has received widespread attention for its beneficial biological function with antioxidant capacity. This study investigated the protective role of TA on the intestinal antioxidant capacity and intestinal barrier in weaned piglets and porcine intestinal epithelial cells (IPEC-J2). A total of 18 weaned piglets were randomly allocated into two groups (n = 9) and fed with a basal diet (control, CON) and a basal diet containing 1,000 mg/kg TA for two weeks. The in vivo results showed that treatment with TA increased both glutathione peroxidase (GSH-PX) activity and the protein expression of ZO-1 in the jejunum of weaned piglets, and reduced the level of malondialdehyde (MDA) in the serum and the mRNA and protein expression of Keap1 in the jejunum of weaned piglets. Furthermore, in vitro results indicated that TA treatment effectively alleviated tert-butyl hydroperoxide (TBH)-induced oxidative stress in IPEC-J2 cells, improved the antioxidant capacity by elevating the cell redox state and activating the Nrf2 pathway, and improved the intestinal barrier by upregulating the mRNA and protein expression of intestinal tight junction proteins and increasing the transepithelial electrical resistance (TEER) value. In conclusion, these results confirmed that TA relieves oxidative injury and improves intestinal barrier function and intestinal antioxidant capacity by activating the Nrf2 signaling pathway. These findings suggest that TA has the potential application in alleviating oxidative stress in the intestine of weaned piglets.

Protective Effect of Sweetpotato (Ipomoea batatas L.) Leaf Phenolic Acids Extract on IL-1β-Induced Barrier Injury of Caco-2 Monolayers

The status quo of a high-fat diet can impair the integrity of the intestinal barrier and promote inflammatory bowel diseases. The exploration of natural products as sources of new lead compounds that control such diseases becomes essential. Sweetpotato leaves (SPLs) have strong biological activity, and their phenolic acids were recently reported to be able to impart antioxidative, anti-inflammatory, and neuroprotection. The aim of this study was to investigate the effects and mechanisms of sweetpotato leaf phenolic acids (SPLPAs) extract on interleukin 1 beta (IL-1β)-induced barrier injury of Caco-2 monolayers. The safety from 0.02 to 0.2 mg/mL SPLPA extracts were demonstrated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) method and Trypan blue staining. The 0.2 mg/mL SPLPA extract significantly decreased the release of Nitric oxide (NO) generation and its contribution to the expression of inflammation-related nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and nuclear factor kappa B (NF-κB) were evaluated. Further investigation suggested that the SPLPA extract inhibited the IL-1β-induced decrease in the transepithelial electrical resistance (TEER) value and could upregulate the IL-1β induced decline in tight junction protein levels. The results suggested that the SPLPA extract could enhance the integrity of Caco-2 monolayers. These results clarified the beneficial effects of SPLPA extract on inflammatory Caco-2 monolayers, indicating that the application of SPLPA extract in medicine and functional food has great potential for exploration.

Crystal structure and properties of layered compounds Fe0.75TiS2–ySey

Layered compounds Fe0.75TiS2–ySey (0 ≤ y ≤ 1) with a metal-to-chalcogen ratio of 7:8 and a monoclinic crystal structure were obtained for the first time by a three-stage solid-phase method and studied by x-ray diffraction and by measuring electrical resistivity, magnetic susceptibility, and magnetization. The substitution of Se for S in the compounds results in an enhancement of the anisotropy of the crystal lattice deformations apparently due to an increase in the covalency of chemical bonds. An increase in the Se content in Fe0.75TiS2–ySey to y = 1.0 leads to a decrease in the magnetic critical temperature Tcrit from 145 K to ∼100 K and to a change in the magnetic behavior from ferrimagnetic toward antiferromagnetic. The higher values of electrical resistivity of Fe0.75TiS2–ySey in magnetically ordered state compared to those observed in the disordered paramagnetic state have been attributed to the inhomogeneity of the magnetic state in this compound below Tcrit due to the mixing of Fe and T atoms in cationic layers.

Preparation and Characterization of Aprepitant Solid Dispersion with HPMCAS-LF.

This study focused on improving the physicochemical characteristics of aprepitant with poor water solubility by preparing solid dispersion (SD). To prepare the SD with HPMCAS-LF, the solvent evaporation method was applied. Based on dissolution analysis, the dissolution rate of SD increased by five times compared with aprepitant. In addition, scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), and differential scanning calorimetry (DSC) results suggested the presence of amorphous-form aprepitant inside SD. According to Fourier transform infrared (FTIR) spectroscopy, intermolecular hydrogen bonds were detected between polymer and aprepitant. The Caco-2 cell experiment proved that SD did not lower the transepithelial electrical resistance (TEER) values but improved the permeation amount of aprepitant. Additionally, the SD of aprepitant displayed excellent stability.