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The use of tacrolimus (FK506) as an immunosuppressant is limited by its low aqueous solubility and bioavailability. The self-microemulsifying drug delivery system (SMEDDS) has successfully improved the solubility of FK506 in our previous study. This study focused on the solidification of liquid SMEDDS to capture the benefits of both liquid SMEDDS and solid dosage forms. Among several porous silica adsorbents evaluated, Aeroperl® 300 Pharma showed the best performance in terms of droplet size, in vitro dissolution, adsorbent-drug compatibility, and tabletabilities. And precoating the adsorbent with polyvinylpyrrolidone K30 resulted in complete drug release. Hydroxypropyl methylcellulose based matrix tablet was developed to achieve a sustained release of FK506. Differential scanning calorimetry and X-ray powder diffraction indicated that FK506 was present in a molecular or amorphous state in the solidified SMEDDS and tablets. In vivo pharmacokinetic studies showed that the self-prepared tablet had improved bioavailability (179.02%) compared to the marketed product Advagraf®. This study provided a promising candidate with improved dissolution and bioavailability for FK506 and a prospective platform for SMEDDS development. [ABSTRACT FROM AUTHOR]

Inorganic membranes are used to effectively capture particulate matter in dust without causing secondary pollution. However, fine dust particles accumulate on the surface and penetrate the structure of inorganic membranes, thereby degrading their performance. This study investigated the influence of the precoating of inorganic membranes with needle‐shaped wollastonite particles on their regeneration efficiency. The filter‐cake‐curing technique was employed, and the results were obtained by characterization methods, including scanning electron microscopy and energy‐dispersive spectroscopy. The mechanism for controlling membrane fouling was examined based on the quantity and depth of particle penetration to the filtration medium and pore structure of the filter cake. The results demonstrated that precoating can prevent fine particles from penetrating the membrane pores, thereby alleviating pore blocking in inorganic membranes. Furthermore, this increased the porosity and decreased the fractal dimension of the pore in the cake, thereby reducing the structural complexity and resistance during cake removal. The regeneration efficiency of the inorganic membrane increased from 59.4% without a precoating to 94.1% when wollastonite particles with an aspect ratio of 10 were used for precoating. [ABSTRACT FROM AUTHOR]

A smooth and dense surface of the base paper is advantageous when the goal is to apply a liquid coating as a barrier layer. For such a base paper, non-wood fibers derived from wheat straw could be an alternative to wood fibers. In this research paper, wheat straw pulp was refined with different beating levels (up to 600 revolutions) followed by different calendering pressure loads (up to 50 N/mm) to test its influence on mechanical and surface properties. Alkyl ketene dimer (AKD) was used as sizing agent with concentrations up to 0.2 wt% followed by a mineral-based precoating to test its influence on the smoothness. Eucalyptus pulp was chosen as a benchmark. After beating, the initial Schopper-Riegler degrees of 28 °SR increased to 56 °SR. Beating also increased the tensile index from 24 to 49 Nm/g, the burst index from 1.2 to 2.8 kPa·m²/g, and the tear index decreased from 3.3 to 2.8 mN·m²/g. Calendering reduced the initial roughness of 370 mL/min to 30 mL/min. When precoated and calendered again, the value was lowered to 15 mL/min. In summary, wheat straw paper is a relevant alternative to wood-derived base paper to produce barrier papers. Compared to eucalyptus, wheat straw paper showed better smoothness and much lower air permeability indicating excellent suitability for barrier coating. [ABSTRACT FROM AUTHOR]

A smooth and dense surface of the base paper is advantageous when the goal is to apply a liquid coating as a barrier layer. For such a base paper, non-wood fibers derived from wheat straw could be an alternative to wood fibers. In this research paper, wheat straw pulp was refined with different beating levels (up to 600 revolutions) followed by different calendering pressure loads (up to 50 N/mm) to test its influence on mechanical and surface properties. Alkyl ketene dimer (AKD) was used as sizing agent with concentrations up to 0.2 wt% followed by a mineral-based precoating to test its influence on the smoothness. Eucalyptus pulp was chosen as a benchmark. After beating, the initial Schopper-Riegler degrees of 28 °SR increased to 56 °SR. Beating also increased the tensile index from 24 to 49 Nm/g, the burst index from 1.2 to 2.8 kPa·m²/g, and the tear index decreased from 3.3 to 2.8 mN·m2/g. Calendering reduced the initial roughness of 370 mL/min to 30 mL/min. When precoated and calendered again, the value was lowered to 15 mL/min. In summary, wheat straw paper is a relevant alternative to wood-derived base paper to produce barrier papers. Compared to eucalyptus, wheat straw paper showed better smoothness and much lower air permeability indicating excellent suitability for barrier coating.

Particle emissions into the atmosphere can cause extensive damage to the environment and human health. To improve the efficiency in the collection of submicronic particles, new filtration media appeared on the market due to new textile technologies and equipment, such as filter media developed with polytetrafluoroethylene (PTFE) membranes; however, these are more expensive. A filter coating technique called precoating is a more economical alternative that could enhance filtration efficiency. This paper aimed to evaluate the operational parameters of precoating for micro- and nanoparticle filtration and compare the results with those obtained from the PTFE membrane. For this purpose, filtration cycles were performed, using precoated polyester with hydrated lime and dolomitic limestone, polyester with a PTFE membrane, and steel industry ultrafine dust. The results showed that the precoated polyester had a longer cycle duration and lower pressure drop than the polyester with a PTFE membrane. Therefore, precoating was shown to be a great alternative to be used in bag filters in steel mills because it presented high collection efficiency for submicronic particles, in addition to increasing the bag lifespan with less energy expenditure. [ABSTRACT FROM AUTHOR]

The influence of precoating colors on the dynamic water penetration behavior of double-coated paper was investigated using a laboratory coater equipped with two coating heads. Emphasis was placed on the effects of the pigment combination and binder type on dynamic water penetration. In addition, the latex content on the surface of the coating layer was examined by UV absorbance analysis. The amount of water that penetrated the base paper was found to be proportional to the square root of the contact time between the coating color and the base paper, regardless of the pigments and binders used. When a large amount of pigment with a fine particle size was used, or the starch binder content was increased, the low shear viscosity of the coating color increased, and the amount of water penetration into the base paper decreased. The UV absorbance analysis showed that higher water holding in the coating color increased the latex content on the surface of the coating layer. Increasing the viscosity or water retention of the coating color was found to reduce the amount of binder migration into the base paper. [ABSTRACT FROM AUTHOR]

N,N'-bis (salicylaldehyde)-1,3-diaminopropane (Salpn) has been evaluated as corrosion inhibition for iron in 0.1 M HCl when the films of Salpn were self-assembled on the surface of iron to improve anticorrosion property of the substrate. Monolayer formation takes place when carbon steel is precoated in hot ethanolic/aqueous 1 mM Salpn solution for 10, 20 and 30 min, and rinsing the physisorbed molecules in distilled water and heating in a hot air oven. The films of Salpn inhibitor were characterized by weight loss method and electrochemical impedance spectroscopy, electrochemical polarization curves. Results revealed that Salpn performed excellently as a corrosion protection for iron in HCl solution. The formations of monolayers were confirmed by SEM study and ATR-FTIR spectra. Taken together, the outcomes of present study exhibited that precoating of Salpn on the substrate surface is able to provide protection efficiency up to 95% and escalating of the soaking time in corrosive environment up to 24 h only reduces slightly protection efficiency (around 6%) implying this layer act as effective corrosion inhibitors. [ABSTRACT FROM AUTHOR]

Filtration of dust nanoparticles emitted from metallurgical processes is currently problematic, due to a rapid increase of the pressure drop and an inefficient filter cleaning, inducing high maintenance costs. This paper investigates the use of precoating technique to overcome the cleaning difficulties caused by the metallic nanoparticles. It consists of protecting the filter surface with a dust layer composed of micron-sized particles that is easily discharged upon cleaning. In this study, the pulse-jet cleaning of flat filters with and without precoating is evaluated. The aim is to determine the effect of operating conditions on the cleaning efficiency and provide guidelines on the application of precoating. Different precoating materials are tested, to determine whether the material choice is of influence. Experimental results highlighted the increase of the collection efficiency and dust holding capacity using precoating. The cleaning efficiency was significantly improved from 10 % without precoating to 90 % with precoating. Clogging/unclogging cycles showed that the use of precoating allowed stabilizing the filtration process. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon-coated LiZnTiO (NC-LZTO) anode material was fabricated with chitin as a carbon source by precoating process via a facile solid-state reaction method. The effects of nitrogen-doped carbon layer on the crystal structure, surface morphology, and electrochemical performances were studied. The NC-LZTO samples show the significant improvement in rate capability compared with carbon-coated LiZnTiO (C-LZTO) sample derived from glucose and naked LiZnTiO (LZTO) sample. At the current rates of 0.5, 1, 2, 5, and 10 C, the discharge-specific capacities of the NC-LZTO sample are 275.6, 262.8, 244.8, 217, and 190.6 mAh g, respectively. After 200 cycles at 2 C, its capacity retention is 98.7%. The increased electrochemical performance of NC-LZTO can be ascribed to the larger specific surface, smaller particle size, and better electronic conductivity. [ABSTRACT FROM AUTHOR]

• An epoxy-acetone solution was employed to repair and improve random defects on concrete surfaces. • The fracture properties of the interface was investigated using DIC technology and the four-point bending test. • An appropriate resin concentration could effectively delay crack formation and markedly improve the fracture properties. • SEM revealed the influence mechanism of the precoating technique with various epoxy resin concentrations. • An appropriate resin concentration could enhance the interfacial connection performance between epoxy mortar and concrete. Random defects on concrete surfaces are a key factor affecting the bonding property of concrete–epoxy mortar interfaces. In this study, an epoxy–acetone solution was employed to pretreat such defects on concrete surfaces, and resin concentrations of 20, 40, 60, and 80 wt% diluted by acetone were used. The fracture mechanical properties and propagations of the fracture process zone (FPZ) of 14 concrete–epoxy mortar composite specimens were analysed using digital image correlation technology and the four-point bending test. The results revealed that there was a great influence of resin concentration on the fracture properties of the concrete-epoxy mortar interface. Precoating solution with an appropriate resin concentration (20 ∼ 40 wt%) could effectively delay crack formation at the interface and markedly improve the bearing capacity, stiffness, ductility, FPZ length, and energy release rate of the specimens. The precoating solution with a resin concentration of 40 wt% exhibited the optimal repair effect on the concrete surfaces. However, the improvement from the pretreatment with high resin concentrations (60 ∼ 80 wt%) on the fracture properties was less than satisfactory. The toughening mechanism of this precoating solution was analysed through scanning electron microscopy, which revealed that the concrete surface could be effectively repaired and improved by the precoating treatment with an appropriate resin concentration, which in turn enhanced the interfacial connection performance between epoxy mortar and concrete. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the Bi2212 superconductor and Cu–Ni metal were soldered with In–Bi alloy at low temperature. In order to improve the contact properties of the solder Cu/Ag precoating layers were applied on the surface of the superconductor by electroplating process. The shear strength of the contact was correlated with the electroplating current density and the Ag layer thickness. The strength increased as the electroplating current density and the Ag layer thickness increased. In the case of Cu/Ag multi-precoating, the contact strength was higher than that of the single Ag precoating layer case. The contact strength also increased when the Ag precoated layer was annealed at the temperature range of 500°C due to better connectivity at the interface layers. [Copyright &y& Elsevier]

Abstract: Polyhydridomethylsilazane was used as a preceramic polymer to fabricate three-dimensional quartz fiber reinforced silicon nitride-based composites, and the effects of precoating process on the mechanical properties and microstructures of the composites were mainly investigated. The composite without precoating process exhibited a brittle fracture surface without fiber pull-out, leading to a low flexural strength of 56.3MPa, while the composite with precoating treatment showed a non-brittle fracture behavior with long fiber pull-out in the fracture surface, resulting in a high flexural strength of 114.5MPa. It was the controlled fiber/matrix interface due to the precoating of the quartz fiber preform that contributed to the high mechanical property of the composite. [Copyright &y& Elsevier]

In this investigation, a comparative study among different types of coating materials to improve the wear resistance of steel was conducted. There were three types of coating material, magnesium zirconate, aluminium bronze, and molybdenum, and mixtures of different percentages of them were used. The influences of load, velocity and counter surface roughness on each type were also determined. It was found that the addition of molybdenum to magnesium zirconate in a sufficient amount helped to increase its wear resistance in comparison to the wear behaviour of pure magnesium zirconate. Scanning electron microscopy and microhardness testing of longitudinal cross-sections of each of the materials were used to explore the reasons behind the interesting behaviour of these composites after abrasive wear testing. It was found that the reason behind the high wear resistance and high microhardness of the magnesium zirconate matrix after the addition of 10% molybdenum was the prevention of the pull out of magnesium zirconate particles. The abrasive wear mechanisms for the spray coated steel appear to be microcracking and microploughing. [ABSTRACT FROM AUTHOR]

Background: The use of alloplastic materials such as polypropylene and polyester has reduced the recurrence of abdominal wall hernias. Concomitantly, new problems have arisen such as inflammatory response against the implanted material and the development of enteric fistulas in case of direct contact of the bowel to polypropylene and polyester. A precoating of the PP with collagen and other absorbable materials seems to reduce the incidence of adhesions and fistulas. The aim of this study was to show the technical feasibility of a precoating of polypropylene with living human fibroblasts and to investigate the growth properties of the cells under these conditions in vitro.Methods: The textile structure of three different alloplastic materials is described (SurgiPro), TycoHealthcare; Parietene3 PP1510, Dallhausen; VIPRO II, Ethicon Endosurgery). Enhanced Green Fluorescence Protein (EGFP) transduced human foreskin fibroblasts (KiF5) were seeded onto these different alloplastic materials. Proliferation was analyzed by FACS analysis of Ki67 expression. The coating process of the whole mesh area was observed over time with UV-light microscopy, immunostaining, and scanning electron microscopy (SEM). The expression of collagen type I and III was investigated by immunostaining.Results: The three alloplastic materials used were knitted fabrics with different textile structures. KiF5 colonized the entire alloplastic material within 4-6 weeks. Cells were proliferating, as detected by Ki67 expression. SEM showed surface ruffles and long cellular extensions, indicating an active cell metabolism. Light microscopy and SEM suggested that the cells modify the apolar surface by deposition of extracellular matrix components before colonization.Conclusion: Our study shows the feasibility of precoating of polypropylene meshes with living human fibroblasts and opens the possibility for clinical use in the future. [ABSTRACT FROM AUTHOR]

Coagulation with only rapid mixing in a separate tank (ordinary coagulation) and coagulation with no mixing tank (in-line coagulation) were applied prior to ultrafiltration with an inside-out type hollow fiber membrane. In result the filterability at the former conditions was superior in both the crossflow and dead-end modes. Thus the relative importance of the removal rate of DOMs was investigated. Precoating the surface of the membranes with metal hydroxide particles of coagulants was also examined. This method of utilizing coagulants resulted in a smaller consumption of coagulant in the coagulation-UF system. [Copyright &y& Elsevier]

• A precoating treatment for concrete–epoxy resin mortar adhesion was proposed. • The failure process at the interface was investigated using the DIC technology. • The precoating treatment changed the failure mode of the interface to quasi-brittle. • The precoating treatment delayed initial cracking of the interface. • SEM revealed the precoating increased the toughness of the interface. The method employed to bond concrete and epoxy mortar determines the strength of the interface in the resulting concrete composite structure. This paper presents a method for improving concrete–epoxy resin mortar adhesion through the precoating of concrete surfaces with resin. Resin concentrations of 10, 20, and 30 wt% were diluted in acetone. The failure process, interface strength, and crack propagation at the interface were investigated using a four-point bending test and digital image correlation technology. Increasing the amount of epoxy resin in the precoating solution improved the load-bearing capacity of the concrete–epoxy resin mortar interface by approximately 15% and changed the failure mode of the interface from near brittle to quasibrittle. Equivalent linear elastic fracture mechanics and double-K criteria analysis of the fracture toughness of the interface revealed that surface precoating considerably delayed initial cracking and improved surface toughness. Scanning electron microscopy of treated and nontreated specimens revealed that the toughness of the interface increased because the resin precoating on the concrete surface increased the area of contact between the epoxy resin mortar and concrete, which enhanced the interlocking effect and improved the strength of the interface. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cyclic RGDyK peptide (cRGD) modified bovine serum albumin (BSA) was designed as a precoating protein corona. • BSA-cRGD (Bc) form steady corona on chitosan-based nano-carriers. • Bc corona enhanced tumor cell targeting and reduced plasma proteins adsorption. • Precoating of Bc corona improved the delivery efficiency of the carriers and therapeutic effect of siVEGF. • Bc precoating provided an effective way to weaken the influence of plasma protein corona on chitosan-based nano-carriers. Spontaneous formation of protein corona on chitosan-based nano-carriers is inevitable once they enter the blood, which is considered to be an important factor that weakens the delivery efficiency and therapeutic effect of nucleic acid drugs. For this, cyclic RGDyK peptide (cRGD) modified bovine serum albumin (BSA) was designed as a corona to precoat on redox-responsive chitosan-based nano-carriers (TsR NPs) before administration. The effects of the precoating corona on the pharmaceutical properties and delivery efficiency of the nano-carriers and the therapeutic effect of model siRNA (siVEGF) were investigated. The results showed that BSA-cRGD formed steady corona around TsR NPs, which enhanced targeting ability to cancer cells and reduced serum proteins adsorption. The Bc corona improved the stability and biocompatibility of TsR NPs, increased the intracellular uptake, facilitated the lysosomal escape and maintained their redox-sensitive responsiveness, resulting in enhanced gene silencing efficiency and anti-tumor proliferation effects both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

• (1) Additions of TPS can improve the consistency, high-temperature stability and viscosity of SBS binder. • (2) Effects of TPS on SBS binder were demonstrated which can provide references for bitumen design. • (3) Two-phase mixing method improves some of the mechanical and functional properties of the modified SBS/TPS porous asphalt. A two-phase mixing method was developed to improve the mechanical properties of hot mix asphalt. The coarse aggregate was precoated with an optimal amount of binder, followed by mixing with fine aggregate, filler, and the remaining amount of bitumen was added. Styrene-butadiene-styrene (SBS) (4%) and Tafpack super (TPS) (6%, 8%, and 10%) were used as bitumen modifiers. The results showed that the two-phase mixing method improved the mechanical properties of the porous asphalt, including splitting, fatigue, and rutting performances. The effects of the method on noise absorption and drainage of the porous asphalt concrete were negligible. [ABSTRACT FROM AUTHOR]

This paper aims to evaluate the effect of pre-coating of forged parts on decarburization in the die forging process. The studies consisted of three stages. In the first instance, different coatings were tested under laboratory conditions by heating steel samples to the temperature of 1200 °C for over five minutes to model the preheating conditions of the induction. Next, testing continued in a commercial forging stand where we tested the effects of different coatings on the rods decarburization during the induction heating process, usually performed before forging. Once completed testing, the measurements and observations of the decarbonized layer were made. The third stage involved analysis of the decarburization of the forged parts after forging. The forged parts were made using precoating of pre-forging elements; pieces cut off a metal rod. Based on tests results, the possibility of using this solution in the technique of industrial hot forging was evaluated. The results of laboratory tests have confirmed that lubrication of metal pieces is sufficient, as well as proved it to be effective in reducing decarburization of the surface layer. Research works conducted in an induction heater showed differences in decarburization depending on a substance and concentration of lubricants that were used. These differences become more apparent when observing the surface layer of the forged parts. Results indicate that decarburization may be reduced to a minimum when we use Bonderite product in a concentration of 66% and 50%. Another lubricant, Berulit 913, may also be used. However, due to burning graphite in high temperatures, reduction of decarburization goes only as far as half of the thickness of the decarbonized layer. Condursal has no significant effect; nevertheless, it protects over the induction heating stage. [ABSTRACT FROM AUTHOR]

Polyborosilazane, a low viscosity preceramic polymer with good infiltration efficiency and high char yield, was used to prepare amorphous composites with polymer derived nitride matrix reinforced by 2·5-dimentional silica fibre, and the mechanical properties and microstructures were investigated. The composites without fibre coating showed typical brittle fracture behaviour with a smooth fracture surface and a longitude flexural strength of just 46·3 MPa whereas the composites with fibre coating exhibited non-brittle fracture behaviour with distinct fibre pull-out on the fracture surface and a high longitude flexural strength of 129·5 MPa. It was the controlled fibre/matrix interface by precoating treatment that contributed to the high mechanical property of the composites. [ABSTRACT FROM AUTHOR]

Phosphor-converted light-emitting diodes (LEDs) were fabricated by precoating blue/green/red phosphors onto near ultraviolate (n-UV) LED chips prior to package into LED lamps. With a 20-mA injection current, it was found that the color temperature Tc was around 5900 K and the color-rendering index Ra was around 75 for the "n-UV+blue/green/red" white LED lamps. It was also found that no changes in color temperature Tc and color-rendering index Ra could be observed when we increased the injection from 20 to 60 mA. These results indicate that such "n-UV+blue/green/red" white LEDs are much more optically stable than the conventional "blue+yellow" LEDs. [ABSTRACT FROM PUBLISHER]

• Solve the fast termination of filtration caused by the rapid increase of the specific resistance of filter cake. • Detection of the particles of trajectory with surface-enhanced Raman spectroscopy. • Analysis of the filtration performance of different precoated material parameters and precoating thickness. • Pilot scale test is considered based on lab scale test. The factors affecting a precoating filtration process and its regulation are studied through lab scale and pilot scale tests combined with surface-enhanced Raman spectroscopy. In the classic filtration process, the diatomite filter aids are introduced for precoating to regulate the specific resistance of the filter cake during the filtration process. This approach solves the fast termination of filtration caused by the rapid increase of the specific resistance of filter cake in classic filtration process. Moreover, surface-enhanced Raman spectroscopy is introduced to detect the trajectory of the filter particles moving with the filtrate in different precoating. The key factors, such as median particle size, thickness, and suspension mass concentration of precoating in the filter aids, are determined using lab scale and pilot scale tests. This study provides a foundation for industrial application of precoating filtration processes. [ABSTRACT FROM AUTHOR]