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В статье рассматриваются основные проблемы здоровьесберегающей деятельности в системе образования: низкий уровень профессиональной компетентности педагогических работников, научно-методической, материально-технической, информационной базы; неудовлетворительное использование здоровьесберегающего потенциала ряда образовательных программ; отсутствие механизма ведомственного и межведомственного сотрудничества, неразвитость нормативно-правовой базы. Ставятся неотложные задачи по решению этих проблем и определяются основные направления деятельности созданного координационного совета по вопросам здоровья обучающихся и педагогов в рамках современной системы образования. The article discusses the main problems of health-saving activities in the education system: low level of professional competence of teaching staff, scientific and methodological, material and technical, information base; unsatisfactory use of health-saving potential of a number of educational programs; lack of a mechanism of departmental and interdepartmental cooperation, underdevelopment of the regulatory framework. Urgent tasks are set to solve these problems and the main activities of the created coordinating council on the health of students and teachers within the framework of the modern education system are determined.

Electric arc furnaces and ladle furnaces have an important role in the future of steelmaking where CO₂ emissions have to be mitigated to an acceptable level. One way to address this goal is to optimize and improve the current practices by adjusting the chemistry and reactions with material additions or gas injections. These procedures would greatly benefit from on-line slag composition analysis. Since the electric arcs radiate throughout the melting, optical emission spectroscopy is a potential method for such analysis. In this study, optical emissions from the electric arc are measured in a laboratory environment. Dozens of atomic emission lines were correlated with Cr₂O₃, Fe₂O₃, Al₂O₃, SiO₂, MnO, MgO, CaO, CaF₂, V₂O₅, and Ni content of the slag together with correlation between CaF₂ and molecular optical emission bands of CaF. Optimal spectral resolution for industrial applications was deducted to be between 0.022 and 0.179 nm.

Photosensors, photodetectors, or color sensors are key components for various optical and optoelectronic applications. Semiconductor-based photodetection has been a dominator which is excellent at measuring the photon intensity of incident light. However, the wavelength of the incident light to be measured must be known beforehand and it mostly depends on auxiliary methods to filter unknown wavelengths. Herein, an alternative but simple mechanism that is using a monolithic, bandgap-engineered photoferroelectric ceramic to blindly determine the wavelength and intensity of incident light at the same time is demonstrated. The photoferroelectric compound is Ba- and Ni-codoped (K,Na)NbO₃ exhibiting a direct bandgap of ≈2 eV and a spontaneous polarization of ≈0.25 C m⁻². The band–band charge carrier transition is confirmed by multiple characterization methods of photoluminescence, photodielectric spectroscopy, and photoconductivity. The existent optoelectrical cumulative effect enabled by the simultaneous narrow bandgap and strong ferroelectricity allows to reliably distinguish the wavelengths of 405, 552, and 660 nm as well as the power density ranging from ≈0.1 to 10 W cm⁻², with the photoresponsivity of up to 60 μA W⁻¹. Consequently, this work proposes an alternative to semiconductor-based counterparts for filterless, wavelength-selective photodetection and color sensing.

Phase-matching the non-degenerate sum-frequency process to a large sideband order is demonstrated to be the key factor allowing to generate the repetition-rate locked two-color bright-soliton frequency combs in chi-2 microresonators with the otherwise large difference of the group velocities, i.e., the walk-off parameter, between the fundamental and 2nd harmonic pulses.

Sm²⁺ and Sm³⁺ co-doped SrB₄O₇ could be utilized in several high-level optical devices and fundamental knowledge about the optical behavior of these materials benefits the development of luminescent applications. Herein, we report luminescence and its vacuum ultraviolet (VUV) excitation spectra in samarium doped SrB₄O₇. Both, Sm²⁺ and Sm³⁺ luminescence centers have been examined and distinguished in the emission and the excitation spectra investigated under synchrotron radiation. The contribution of either Sm²⁺ or Sm³⁺ emission lines into the emission spectra heavily depended on the excitation energy, and strong f-f transitions of both Sm²⁺ and Sm³⁺ were detected. At 10 K, a broad intrinsic luminescence in the UV range was detected and attributed to the radiative transition of either bound or self-trapped exciton in SrB₄O₇. The optical behavior, including e.g. inter-configurational f-d transitions of Sm(n+) were elucidated with first-principles calculations. Partial density of states well represents the changes of the electronic states that are related to the samarium doping, which in turn explains the emerging features in excitation spectra. In summary, the obtained results clarify the excitation and emission behavior of samarium doped SrB₄O₇.

Synchrotron radiation is applied to study visible and UV luminescence spectra and their excitation spectra of undoped as well as In and Sb doped cadmium iodide crystals at 10 K. The origin of principal luminescence bands and the role of impurities in the formation of emission centers are discussed. The luminescence properties have been explained based on the electronic structure of CdI$_2$ crystals.