Few-layer MoS2 films stay at the forefront of current research of two-dimensional materials. At present, continuous MoS2 films are prepared by chemical vapor deposition (CVD) techniques. Herein, we present a cost-effective fabrication of the large-area spatially uniform films of few-layer MoS2 flakes using a modified Langmuir–Schaefer technique. The compression of the liquid-phase exfoliated MoS2 flakes on the water subphase was used to form a continuous layer, which was subsequently transferred onto a submerged substrate by removing the subphase. After vacuum annealing, the electrical sheet resistance dropped to a level of 10 kΩ/sq, being highly competitive with that of CVD-deposited MoS2 nanosheet films. In addition, a consistent fabrication protocol of the large-area conductive MoS2 films was established. The morphology and electrical properties predetermine these films to advanced detecting, sensing, and catalytic applications. A large number of experimental techniques were used to characterize the exfoliated few-layer MoS2 flakes and to elucidate the formation of the few-layer MoS2 Langmuir film.

Nanocrystalline ZnO films were deposited onto glass substrates in the temperature range of 473-673 K using pulsed spray pyrolysis. The structural, substructural, and optical properties of the films were investigated by means of X-ray diffraction analysis, Raman scattering, and Fourier transform infrared (FTIR) spectroscopy. The effect of the substrate temperature (T s ) on the coherent scattering domain (CSD) sizes L, microstrains e, and microstress s grades, and the average density of dislocations r in the films were estimated through the broadening of X-ray lines using the Cauchy and Gauss approximations and the threefold function convolution method. The ZnO films grown at T s ¼ 623-673 K possessed the highest values of L, and the lowest of e, s, and r, indicating high-crystalline quality. The Raman spectra showed peaks located at 95-98, 333-336, 415, 439-442, 572, and 578-584 cm À1 , which were interpreted as E 2 low (Zn), (E 2 high ÀE 2 low ), E 1 (TO), E 2 high (O), A 1 (LO) and E 1 (LO) phonon modes of the ZnO wurtzite phase. The FTIR spectra showed relatively weak signals at 856, 1405, and 1560 cm À1 , corresponding to the C-H and C-O stretching modes, in addition to the main Zn-O mode at 475 cm À1 , indicating a low content of precursor residues.

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Recent advances in the liquid-phase exfoliation enabled large-scale production of two-dimensional (2D) materials, including few-layer graphene and transition metal dichalcogenides. The exfoliated flakes of 2D materials allow cost-effective deposition of continuous films for various applications ranging from optoelectronics to lubrication technology. The self-assembly of 2D materials on water subphase and subsequent transfer of such a Langmuir film onto a solid substrate offers an unprecedented layer quality in terms of spatial homogeneity as it proceeds in thermodynamic equilibrium. However, while the formation of conventional organic molecular Langmuir films has been widely studied, the application of the Langmuir technique to rigid inorganic 2D materials is still rather unexplored.Here, we study the underlying mechanism behind the formation and collapse at the critical surface pressure of the Langmuir film composed of few-layer MoS 2 flakes. The in situ wide-angle X-ray scattering measured in real time and other supportive techniques applied ex situ after the film transfer onto a Si/SiO 2 substrate were employed. We identify all principal compression stages up to the Langmuir monolayer collapse and beyond, relying on the texture, surface pressure, and elastic modulus temporal evolution. The results obtained and the conclusions drawn can be extended to a large family of the inorganic Langmuir films of other 2D materials to optimize the deposition process for envisaged application.

Abstract. We present the numerical optimization and the technological development progress of x-ray optics based on asymmetric germanium crystals. We show the results of several basic calculations of diffraction properties of germanium x-ray crystal monochromators and of an analyzer-based imaging method for various asymmetry factors using an x-ray energy range from 8 to 20 keV. The important parameter of highly asymmetric monochromators as image magnifiers or compressors is the crystal surface quality. We have applied several crystal surface finishing methods, including advanced nanomachining using single-point diamond turning (SPDT), conventional mechanical lapping, chemical polishing, and chemomechanical polishing, and we have evaluated these methods by means of atomic force microscopy, diffractometry, reciprocal space mapping, and others. Our goal is to exclude the chemical etching methods as the final processing technique because it causes surface undulations. The aim is to implement very precise deterministic methods with a control of surface roughness down to 0.1 nm. The smallest roughness (∼0.3 nm), best planarity, and absence of the subsurface damage were observed for the sample which was machined using an SPDT with a feed rate of 1 mm∕min and was consequently polished using a fine polishing 15-min process with a solution containing SiO 2 nanoparticles (20 nm).

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Nowadays hackers are able to find many software vulnerabilities, which can be exploited for malicious purposes such as to destroy the operating system, to steal users' private data, to demand a ransom not to affect the data and retain their validity. The majority of attacks use an Internet connection; therefore, the efforts should be directed to the way in which data packets are transmitted. The hardware-software complex, which is the main subject of the presented research, serves as a firewall for the devices on one subnetwork with access to the Internet, simultaneously analysing and filtering both downstream and upstream traffic at packet level, resolving scumware and securing the perimeter of each device in the subnet. The concept and the architecture of the developed hardware-software complex are described. The implemented complex will not allow malicious traffic to pass through, providing protection of all endpoint devices in a subnetwork. The experimental results of malware detected are presented, and the security related metrics are evaluated.