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For modern information, measuring, and optoelectronic systems based on micro- and nanomechanical sensors of angular velocity and linear acceleration, it is important to ensure their stable functioning in the presence of external factors. The paper presents the results of a study of the effect of a random vibration on the characteristics of micromechanical accelerometers (MMAs) obtained using the LDS V455 vibration bench. The dependence of the spectral density of vibration acceleration on the frequency of one of the samples, intended for acceleration measurements in the range up to ±1.2 g, has a noticeable shift from its predetermined profile. To establish the reasons for this discrepancy, the design of the MMAs’ sensitive element (SE) under the effect of a random vibration is studied. Calculations and simulations are performed in the ANSYS program. The deformations of the MMAs’ SE along the sensitivity axis Z and the capacitance changes due to the acceleration and random vibration along the X, Y, and Z axes, taking into account the crystallographic orientation of the SE’s material (silicon) are determined. The effect of the crystallographic orientation of silicon used to manufacture the MMAs’ SE on the deformation (deflection) of the rotor is considered. The presented results of the theoretical and experimental studies, as well as computer modeling, coincide, which allows us to improve the design of the MMAs’ SE.

A micromechanical accelerometer (MMA) is used to measure the acceleration based on the change in frequency of the resonator when the acceleration is caused by the displacement of the inertial mass. Its sensitivity can be influenced by factors such as vibration noise and temperature. In this study, using the calculation and modeling in the ANSYS program, the influence of the temperature on the natural oscillation frequency of resonators of various designs has been studied. It is shown that in a number of the studied designs of frequency MMA resonators, the frequency change ∆f0 caused by an increase in temperature is comparable and even exceeds the change in the frequency due to the acceleration effect. It is shown that the known designs of resonators whose operation is based on the oscillations of a beam fixed at both ends do not ensure the stability of oscillations at their natural frequency with a change in temperature. For resonators based on the oscillations of a cantilever beam, the frequency barely changes due to the increase in temperature. The best result from the point of view of the temperature’s stability is obtained for a resonator in the form of a cantilever beam with the beam resonator inside it, for which the frequency change ∆f0 with the temperature increasing up to 70°C was only 4 Hz. The study of the basic MMA construction, consisting of an inertial mass with a resonator made in the form of a cantilever beam with a resonator inside shows that the natural oscillation frequency of this construction is stable when the temperature increases up to 70°C. In this case, the sensitivity is 130 Hz/g and does not depend on temperature.

Two previously obtained, full-size, fully human antibodies that reversibly bind the active form of an enzyme belonging to the subtype EC 3.2.1, which is used for substitutive enzymatic therapy in lysosomal storage diseases, have been characterized by surface plasmon resonance and biolayer interferometry methods. It was shown under normal physiological conditions that the designed antibodies specifically bound with the antigen (KD ~ 10–8 M) and rapidly dissociated at neutral pH in 60% ethylene glycol while leaving the enzymatic activity unchanged. Dan ue to their properties, the developed antibodies can be used in industry as affinity ligand in the isolation of therapeutic substances of the enzyme.

IR spectroscopic techniques widely used to determine the thickness and refractive index of layers and thin films of various materials are adapted for determining those of hydrogenated silicon layers. Based on a literature analysis, three formulas are chosen which enable the refractive index and thickness of such layers to be determined from reflection and transmission spectra. The formulas are applicable, with some restrictions, to other samples in the form of relatively transparent layers (films) on transparent substrates. Experimental data are presented that illustrate the use of the formulas.

Effect of nitrosomethylurea on the embryonic and larval development of two carp Cyprinus carpio strains (Angelinskii mirror and Angelinskii scaled) is studied. The ambiguous effect of the toxicant on the survival of the eggs and offspring is revealed. Dynamics of morphotype variation is analyzed by the methods of multivariate statistics. In the conditions of ecological risk, a stable development and a large adaptation potential are proposed for Angelinskii scaled carp in comparison to Angelinskii mirror carp.

Proton-implanted (100) KEF-4.5 (phosphorus-doped) silicon wafers 460 μm in thickness have been studied by IR spectroscopy in an on-axis geometry. The implantation process has been run at increased proton energies and current densities to rather high implant doses, up to 7.1 × 1017 H+/cm2. The results are used to identify the structure of chemical bonds in the hydrogen centers produced by the implantation and subsequent annealing at 550°C. We show that the assignment of absorption bands to particular Si-H x (x = 1–3) bonds must take into account the substrate temperature during the implantation process and the annealing temperature.

The results on the application of the research technique developed for measuring micromechanical element parameters are reported. This technique was used in combination with calculation results to determine the parameters of micromirror prototypes.