Complex Films Research Articles

Preparation of orally disintegrated membranes from liquorice inclusion complexes

Objective: to prepare and evaluate orally disintegrating films of liquorice inclusion complexes. Methods: the active components of Chinese liquorice were extracted by pressurised extraction technique, and the inclusion complexes were prepared by antisolvent method, while the buccal disintegration films of liquorice inclusion complexes were prepared by solvent casting method, and the prepared buccal disintegration films were evaluated. Results: the home-made liquorice inclusion complexes orally disintegrated films formed better films, had good hardness and toughness, the thickness was around 0.1 mm and could disintegrate within 40 s, and the dissolution was rapid, the cumulative release reached 80.1% within 10 min, reaching the immediate release effect. Conclusion: the prepared buccal disintegrating membranes of liquorice inclusion complexes, which are expected to provide new ideas for the development and study of other drugs in the future, deserve further investigation.

9-Borafluoren-9-yl and diphenylboron tetracoordinate complexes of F- and Cl-substituted 8-quinolinolato ligands: synthesis, molecular and electronic structures, fluorescence and application in OLED devices.

Six new four-coordinate tetrahedral boron complexes, containing 9-borafluoren-9-yl and diphenylboron cores attached to orthogonal fluorine- and chlorine-substituted 8-quinolinolato ligand chromophores, have been synthesised, characterised, and applied as emitters in organic light-emitting diodes (OLEDs). An extensive steady-state and time-resolved photophysical study, in solution and in the solid state, resulted in the first-time report of delayed fluorescence (DF) in solid films of 8-quinolinolato boron complexes. The DF intensity dependence on excitation dose suggests that this emission originates from triplet-triplet annihilation (TTA). Density functional theory (DFT) and time-dependent density functional theory (TDDFT) studies give insight into the ground and excited state geometries, electronic structures, absorption energies, and singlet-triplet gaps in these new organoboron luminophores. Finally, given their highly luminescent behaviour, organic light-emitting diode (OLED) devices were produced using the synthesised organoboron compounds as emissive fluorescent dopants. The best OLED displays green-blue (λmaxEL = 489 nm) electroluminescence with an external quantum efficiency (EQE) of 3.3% and a maximum luminance of 6300 cd m-2.

Chemical synthesis of complex oxide thin films and freestanding membranes.

Oxides offer unique physical and chemical properties that inspire rapid advances in materials chemistry to design and nanoengineer materials compositions and implement them in devices for a myriad of applications. Chemical deposition methods are gaining attention as a versatile approach to develop complex oxide thin films and nanostructures by properly selecting compatible chemical precursors and designing an accurate cost-effective thermal treatment. Here, upon describing the basics of chemical solution deposition (CSD) and atomic layer deposition (ALD), some examples of the growth of chemically-deposited functional complex oxide films that can have applications in energy and electronics are discussed. To go one step further, the suitability of these techniques is presented to prepare freestanding complex oxides which can notably broaden their applications. Finally, perspectives on the use of chemical methods to prepare future materials are given.

Interface-related phenomena in epitaxial complex oxide ferroics across different thin film platforms: opportunities and challenges.

Interfaces in complex oxides give rise to fascinating new physical phenomena arising from the interconnected spin, lattice, charge and orbital degrees of freedom. Most commonly, interfaces are engineered in epitaxial superlattice films. Of growing interest also are epitaxial vertically aligned nanocomposite films where interfaces form by self-assembly. These two thin film forms offer different capabilities for materials tuning and have been explored largely separately from one another. Ferroics (ferroelectric, ferromagnetic, multiferroic) are among the most fascinating phenomena to be manipulated using interface effects. Hence, in this review we compare and contrast the ferroic properties that arise in these two different film forms, highlighting exemplary materials combinations which demonstrate novel, enhanced and/or emergent ferroic functionalities. We discuss the origins of the observed functionalities and propose where knowledge can be translated from one materials form to another, to potentially produce new functionalities. Finally, for the two different film forms we present a perspective on underexplored/emerging research directions.

Intrinsic giant magnetoresistance due to exchange-bias-type effects at the surface of single-crystalline NiS2 nanoflakes.

The coexistence of different properties in the same material often results in exciting physical effects. At low temperatures, the pyrite transition-metal disulphide NiS2 hosts both antiferromagnetic and weak ferromagnetic orders, along with surface metallicity dominating its electronic transport. The interplay between such a complex magnetic structure and surface-dominated conduction in NiS2, however, is still not understood. A possible reason for this limited understanding is that NiS2 has been available primarily in bulk single-crystal form, which makes it difficult to perform studies combining magnetometry and transport measurements with high spatial resolution. Here, NiS2 nanoflakes are produced via mechanical cleaving and exfoliation of NiS2 single crystals and their properties are studied on a local (micron-size) scale. Strongly field-asymmetric magnetotransport features are found at low temperatures, which resemble those of more complex magnetic thin film heterostructures. Using nitrogen vacancy magnetometry, these magnetotransport features are related to exchange-bias-type effects between ferromagnetic and antiferromagnetic regions forming near step edges at the nanoflake surface. Nanoflakes with bigger steps exhibit giant magnetoresistance, which suggests a strong influence of magnetic spin textures at the NiS2 surface on its electronic transport. These findings pave the way for the application of NiS2 nanoflakes in van der Waals heterostructures for low-temperature spintronics and superconducting spintronics.

«Киноатлас СССР»: концепция М. В. Налетного. По архивным материалам 1920-х гг.

The 1920s saw an increased general release of documentaries about life of peoples and regions in the USSR, opening an opportunity for mass audience to make virtual trips through multinational and diverse country. It was within the frameworks of the project “Cinema-Atlas of the USSR,” an ambitious state program launched under the auspices of the Central Executive Committee, which involved creation of a 150-episode thematic film almanac. The article is to introduce into scientific use the archival documentary film “To the shores of the Pacific Ocean” (1927) directed by M. V. Naletny, created during complex film expedition along the Trans-Siberian railway from Moscow to the Far East. To achieve this goal, not only the film itself is analyzed, but also socio-political, cultural, and ideological context of its creation, in line with the state program for creation of the Soviet Cine-Atlas. Little-known visual and text archives, as well as data from the Soviet periodical press of the 1920s, are used as a source base for the study. Due to specifics of silent cinema, this film is a film text of a kind, consisting of approximately equal number of alternating film frames and text captions. One can tell that, in accordance with general recommendations for film making in the USSR, based on Marxist theory, the director designed his full-length film as a series of visual essays suitable for the “Cinema-Atlas” developed at the time. The study makes it obvious that M. V. Naletny sought in his film to overcome the format of superficial “tourist” narrative, widespread at the time, detailing geographical features of regions, types of population, their economic structures, etc. M. V. Naletny’s methodological developments, which are considered cocurrently, clearly demonstrate party requirements to capacious resources of cinematography as a means of information and agitation, textbook, and means for popularization of scientific knowledge. It is concluded that M. V. Naletny’s legacy is of multi-layered popular science significance, having become a contribution to the on-screen chronicle of Soviet transformations on the ground. The studied complex of materials is a significant example of visual and anthropological searches of the early Soviet period, as well as an informative historical source that has not lost its relevance for modern scientific study.

Preparation of DNA Ion Complex Films Using a Hot-Press Molding and Their Antibacterial Functions

Preparation of DNA Ion Complex Films Using a Hot-Press Molding and Their Antibacterial Functions

Edible pH sensitive polysaccharide-anthocyanin complex films for meat freshness monitoring

One of the innovative methods for real-time determination of food freshness is the application of pH-indicator sensors, where the color change can be used for the visual detection of acidic/basic volatile compounds formed during product storage due to microbial growth. The aim of the present study is to develop a pH-responsive freshness indicator based on anthocyanins from chokeberry (Aronia melanocarpa Elliot) and black carrot (Daucus carota ssp. sativus var. atrorubens Alef.), incorporated into an alginate/pectin/arabic gum composite film. The resulting films show distinct color changes as the pH varies. The color changes from red (pH 2.0 - 3.0) through pink and pale pink (pH 4.0, 5.0 and 6.0) to purple and blue (pH 7.0 - 8.0). The most distinct is the color transition between pH 6.0 and 7.0 for the black carrot extract and the chokeberry: black carrot mixture (1:3). The applicability of the developed pH-indicator films was demonstrated in chicken meat by tracking the changes during its storage at 4°C for 7 d. The observed results show a distinct color change from pink (day 1-3) to violet and blue on day 7. The developed pH- sensitive films have potential for use in a smart packaging system as a sensor for meat freshness monitoring.

Incorporation of cinnamon essential oil-loaded Pickering emulsion for improving antimicrobial properties and control release of chitosan/gelatin films

In this research, cinnamon essential oil (CEO) loaded Pickering emulsion was incorporated into chitosan (CS)/gelatin (GEL) complex films. These antimicrobial functionalizations of biobased packaging films containing different contents (5, 7.5, and 10 mL) of CEO-loaded Pickering emulsion were evaluated on the microstructure, physicochemical, mechanical, barrier and antimicrobial properties. CEO-loaded Pickering emulsion was herein prepared with zein nanoparticles as a stabilizer showed an average size of 113.37 nm and exhibited excellent physical stability. Fourier transform infrared spectroscopy (FTIR) and wide-angle X-ray scattering (WAXS) analyses revealed that the CEO-loaded Pickering emulsion showed compatibility with CS/GEL matrix. Not only mechanical properties but also barrier properties of the prepared films were significantly improved (P < 0.05) by incorporating CEO-loaded Pickering emulsion. Furthermore, incorporating CEO-loaded Pickering emulsion with CS/GEL led to the formation of high antimicrobial against Pseudomonad paralactis MN10 and Lactobacillus sakei VMR17 with slow-release behavior of CEO. These results suggested that Pickering emulsion is a promising antimicrobial agent delivery system for biopolymer based active packaging, notably for the conception of novel active packaging biobased polymers.

The Simultaneous Removal of Ammonium and Manganese from Surface Water in South China by Manganese Co-Oxide Film.

Exceeding the permitted manganese (Mn2+) and ammonium (NH4+-N) levels is a frequent seasonal occurrence in a water treatment plant in south China. An iron Fe-Mn complex oxide film was found capable of removing more than 95% of Mn2+ and NH4+-N at a water temperature of 20 °C and an alkalinity level of 30 mg/L. It could remove up to 5.5 mg/L of Mn2+ and up to 3.5 mg/L of NH4+-N in a stable manner. Alkalinity is a crucial factor in the removal process. The morphology, elemental composition, and micro-structure of the oxide film were investigated using a scanning electron microscope, an energy-dispersive spectrometer, a Brunauer-Emmett-Teller specific surface-area analyzer, an X-ray diffractometer, and a Fourier-transform infrared spectrometer. The capacity of the Fe-Mn complex oxide film on the surface of the filter medium increased appreciably as its content and specific surface area increased. This research, which provides a theoretical basis for simultaneous manganese and NH4+-N removal by catalytic oxidation, demonstrates an engineering reference value.

Transfer of media characteristics in Preston Sturges’s screwball comedy Unfaithfully Yours (1948)

Unfaithfully Yours (Preston Sturges, 1948) is a complex film with an intricate play on the transfer of media characteristics among dissimilar media. In this article, the source of the theoretical approach is mainly Lars Elleström’s (2014); its presentation in Bruhn and Schirrmacher (2022) is also used as a reference. The case study focuses on the performance of two Overtures of operas and a tone poem for a concert. In the film, they are used both in the representation of the concert, and as film music, the main character being an orchestra conductor who eventually imagines secret revenge dramas and becomes the sound recorder of three fiction films. The four modalities of media interact in Sturges’s film with great variety, during the rehearsal of Rossini’s Overture before the concert, or during the concert as we share the conductor’s mind busy satisfying his secret obsessions, and even, after the concert, when the material and sensorial modalities of sounds appear in the screening of objects. The main point of the transfer of these media characteristics is how they interact in the spectator’s mind; moreover, they either arouse emotions that are shared with the characters, or laughter owing to burlesque effects thus created.

Machine Learning-Based Characterization of the Nanostructure in a Combinatorial Co-Cr-Fe-Ni Compositionally Complex Alloy Film.

A novel artificial intelligence-assisted evaluation of the X-ray diffraction (XRD) peak profiles was elaborated for the characterization of the nanocrystallite microstructure in a combinatorial Co-Cr-Fe-Ni compositionally complex alloy (CCA) film. The layer was produced by a multiple beam sputtering physical vapor deposition (PVD) technique on a Si single crystal substrate with the diameter of about 10 cm. This new processing technique is able to produce combinatorial CCA films where the elemental concentrations vary in a wide range on the disk surface. The most important benefit of the combinatorial sample is that it can be used for the study of the correlation between the chemical composition and the microstructure on a single specimen. The microstructure can be characterized quickly in many points on the disk surface using synchrotron XRD. However, the evaluation of the diffraction patterns for the crystallite size and the density of lattice defects (e.g., dislocations and twin faults) using X-ray line profile analysis (XLPA) is not possible in a reasonable amount of time due to the large number (hundreds) of XRD patterns. In the present study, a machine learning-based X-ray line profile analysis (ML-XLPA) was developed and tested on the combinatorial Co-Cr-Fe-Ni film. The new method is able to produce maps of the characteristic parameters of the nanostructure (crystallite size, defect densities) on the disk surface very quickly. Since the novel technique was developed and tested only for face-centered cubic (FCC) structures, additional work is required for the extension of its applicability to other materials. Nevertheless, to the knowledge of the authors, this is the first ML-XLPA evaluation method in the literature, which can pave the way for further development of this methodology.

In Situ Release of Ulvan from Crosslinked Ulvan/Chitosan Complex Films and Their Evaluation as Wound Dressings.

When a wound forms due to any injuries, it should be covered with a functional wound dressing for accelerating wound healing and reducing infection. In this study, crosslinked ulvan/chitosan complex films were prepared with or without the addition of glycerol and chlorophyll, and their wound healing properties were evaluated for potential application in wound dressing. The results showed that the tensile strength and elongation at break of the prepared ulvan/chitosan complex films were 2.23-2.48 MPa and 83.8-108.5%, respectively. Moreover, their water vapor transmission rates (WVTRs) were in the range of 1791-2029 g/m2-day, providing suitable environment for wound healing. Particularly, these complex films could release ulvan in situ in a short time, and the film with chlorophyll added had the highest release rate, reaching 62.8% after 20 min of releasing. In vitro studies showed that they were biocompatible toward NIH 3T3 and HaCaT cells, and promoted the migration of NIH 3T3 cells. These complex films could protect HaCaT cells from oxidative damage and reduce the production of reactive oxygen species (ROS); the addition of chlorophyll also effectively reduced the inflammatory response induced by LPS as found in the reduction in both NO and IL-6. Animal models showed that the complex films added with glycerol and chlorophyll could promote wound healing in the early stage, while accelerating the regeneration of dermal glands and collagen production. Briefly, these ulvan/chitosan complex films had good physiochemical properties and biological activity, and could accelerate wound healing both in vitro and in vivo.

Towards improved performance of waterborne polymer dispersions through creation of dense ionic interparticle network within their films

To overcome the main challenge of low performance of the waterborne polymer coatings due to the particulate nature of the polymer dispersions and the complex film formation process, in this work we implemented the strategy of ionic complexation between oppositely charged waterborne polymer particles. For that aim, doubled charged ionic monomers ithaconic acid (IA) and styrenic 1,4-diazabicyclo[2.2.2]octane (DABCO) were used to densely functionalize (meth)acrylic film forming polymer particles, synthesized by seeded semi-batch emulsion polymerization to produce high solids content anionically and cationically charged polymer dispersions, respectively. The main advantage of the double charges in the selected ionic monomers is that they provide high ionic charge density onto charged particles at lower content of ionic monomers.The blending of these oppositely, densely charged and concentrated dispersions resulted in instantaneous coagulation. To postpone the immediate complexation, water-soluble non-ionic polymeric stabilizing species as steric obstacles around the colloids were employed, which allowed to prepare colloidally stable blends and to prepare ionic complexed films. Certainly, the established ionic complexes between carboxylic acids of IA anionic monomer and quaternary ammonium groups of DABCO units within the films improved substantially the mechanical properties and the water sensitivity of the ionic complexed polymeric films with respect to individual films and the reference blend, in which ionic bonding was prevented by pH control. Moreover, the dense ionic network formed within the film actuated as a strong barrier to the leakage of all the water-soluble species during film immersion in water. Beside simple strategy towards improved performance of waterborne coatings, these results offer further extension of their application potential.

Reflections on the healing power of collaborative filmmaking

Reflections on the healing power of collaborative filmmaking

FABRICATION A NEW FILM SCINTILLATOR BASED ON (8-HYDROXYQINOLATE) LITHIUM

Thin luminescent films of the organometallic complex of lithium 8-hydroxyquinolate (Liq) on glass substrates were fabricated by capillary deposition and lithography. A study of the spectral-luminescent properties of the obtained film structures was carried out. The analysis of the surface of the films was carried out. The light yield and the kinetics of scintillation emission of the obtained film structures are estimated.

Protection of galvanized steel using benzotriazole as a corrosion inhibitor in simulated concrete pore solution and alkali-activated fly ash solution

In this study, the natural passivation ability and chloride-induced subsequent increased levels of corrosion behaviour of galvanized steel in simulated concrete pore (SCP) solution and alkali-activated fly ash (AAFA) solution, with and without benzotriazole (BTA), were evaluated using corrosion potential (Ecorr), linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS) and cyclic potentiodynamic polarization (CPP). In addition, scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDS) were used to observe the morphologies of passive layers and corrosion products of galvanized steel. It was highlighted that the hydrogen evolution could be prevented by AAFA solution to some extent, thus providing a new insight on the inhibition of hydrogen evolution for galvanized steel in concrete. Moreover, due to the formation of a complex protective film, galvanized steel in AAFA solution exhibited significantly higher corrosion resistance to chloride attack than that exposed to SCP solution, which could be further enhanced by the addition of BTA.

Comprehensive demonstration of spin Hall Hanle effects in epitaxial Pt thin films

We demonstrate a nonlinear Hall effect due to the boundary spin accumulation in Pt films grown on Al2O3 substrates. This Hall effect and the previously demonstrated Hanle magnetoresistance provide a complete picture of the spin-precession control of the spin and charge transport at the boundary of a spin-orbit coupled material, which we refer to as spin-Hall Hanle effects (SHHE). We also show that the SHHE can be employed to measure the spin diffusion length, the spin-Hall angle, and the spin relaxation time of heavy metal without the need of magnetic interface or the input from other measurements. The comprehensive demonstration of SHHE in such a simple system suggests they may be ubiquitous and needs to be considered for unravelling the spin and charge transport in more complex thin film structures of spin-orbit coupled materials.

Superior wear resistance in a TaMoNb compositionally complex alloy film via in-situ formation of the amorphous-crystalline nanocomposite layer and gradient nanostructure

Metallic alloys with exceptional wear resistance have long been an attractive prospect for their enhanced safety, reliability, and service duration. Herein, we propose a strategy to achieve superior wear resistance via the in-situ formation of an amorphous-crystalline nanocomposite layer and gradient nanostructure during wear at elevated temperatures. This strategy was demonstrated in a compositionally complex alloy TaMoNb film with a columnar grain structure upon sliding wear at 300 °C. In contrast to the surface layer formed at room temperature (RT), which consists of irregularly shaped TaMoNb nanograins with non-uniform size and distribution in the amorphous oxide matrix, a dense 300 nm-thick nanocomposite layer comprising equiaxed nanograins of only ∼6 nm embedded in the amorphous oxide matrix is formed during wear at 300 °C, below which is a 600 nm-thick plastic-deformation region that exhibits gradient nanostructure. The microstructure induced by wear at 400 °C shows the presence of a 30 nm-thick amorphous layer below the nanocomposite surface layer but no appreciable plastic deformation in the base film. Consequently, the TaMoNb film exhibits a remarkably low wear rate upon wear at 300 °C that is less than 25% of those at RT and 400 °C. Such superior wear resistance is attributed to the specific wear-induced microstructure generated at 300 °C, which has high strength and large homogeneous deformation. Thus, this work offers a new strategy for designing self-adaptive wear-resistant alloys for application in extreme thermo-mechanical service environments.

Design of experiments to investigate multi-additive cellulose nanocrystal films.

Cellulose nanocrystal (CNC) suspensions can self-assemble into chiral nematic films upon the slow evaporation of water. These films are brittle, as indicated by their fracturing instead of plastically deforming once they are fully elastically deformed. This aspect can be mediated to some extent by plasticizing additives, such as glucose and glycerol, however, few reports consider more than one additive at a time or address the influence of additive content on the homogeneity of the self-assembled structure. In this work, design of experiments (DoE) was used to empirically model complex film compositions, attempting to relate additive concentrations in dilute suspension to film properties, and to understand whether outcome specific predictions are possible using this approach. We demonstrate that DoE can be used to predict film properties in multi-additive systems, without consideration given to the different phenomena that occur along the drying process or to the nature of the additives. Additionally, a homogeneity metric is introduced in relation to chiral nematic organization in CNC films, with most of the additive-containing compositions in this work found to reduce the homogeneity of the self-assembly relative to pure CNC films.