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Feverfew is a well-known medicinal plant as a source of the sesquiterpene lactones, the main one is a parthenolide (about 85%). Owing to the parthenolide, feverfew herb has anti-inflammatory activity and it is widely used for prevention of migraine. The aim was to study the qualitative composition and quantitative content of the parthenolide in the samples of the feverfew herb cultivated in Ukraine and to study the influence of environmental factors on the accumulation of parthenolide.

17G1S steel is widely used in pipelines. Change in the physical properties of this material with time depends on the conditions of gas pipeline operation and pipe environment. Material damage due to operating time by far not always leads to a change of such standard characteristics of the material as σt, σy, К1C and a number of others. At the same time, such material can be significantly damaged, but the traditional methods do not allow determining it. The objective of this work is to demonstrate the sensitivity of acoustic emission method to changes in 17G1S steel properties after 15 years of the main gas pipeline operation. Testing results show that the analyzed acoustic emission parameters change essentially under the impact of operating time, and they can be the characteristics for evaluation of the current state of the damaged material. [ABSTRACT FROM AUTHOR]

The paper deals with the main provisions of the new standard DSTU 9118:2022 «Technical diagnostics. Diagnosing the technical condition of structure materials. General requirements». The standard covers industrial facilities: pipelines, pipeline systems, and technological equipment (boilers, containers, tanks, etc.) of power, oil processing, petrochemical and chemical productions, lifting equipment and facilities and other high-risk welded structures. The standard defines the main provisions on technical diagnostics, its indices and characteristics, and requirements to diagnostic support of the facility. The standard is designed for personnel, specialists, and executives, involved in assessment of the technical conditions of the facilities. Application of AE method in the mode of continuous monitoring to ensure fulfillment of the Standard provisions is considered. 5 Ref., 2 Tabl., 3 Fig. [ABSTRACT FROM AUTHOR]

The majority of existing structures contain welded joints. Questions of monitoring service characteristics of welded joints, using acoustic emission method, are considered. Attention is given to a change in material properties of operating structures with welded elements after long-term service, taking into account the time and probable violation of service conditions. Examples of evaluation of the change in properties of welded structure materials by the data of acoustic emission, determination of their damage and residual service life, are given. 17 Ref., 5 Tables, 24 Figures. [ABSTRACT FROM AUTHOR]

The majority of existing structures have welded joints. It is of considerable interest to determine the differences in acoustic emission for various types of welded joints and change of the properties of materials in operating structures, which have welded elements, after long-term service, taking into account the time and probable violation of service conditions. The data of testing samples from such materials demonstrate the high sensitivity of acoustic emission method to welded joint type, and to changes of weld service properties. [ABSTRACT FROM AUTHOR]

In this paper, we study the second-order quasilinear elliptic equations with slow-increasing coefficients on the Euclidean space R¹ , , l ≤ 3. We significantly broaden the concept of equation by introducing the weak coercitivity instead of the strong one. Our results show that this equation doesn't satisfy the existence conditions of the solution "in the small". [ABSTRACT FROM AUTHOR]

We consider the smoothness of solutions of quasilinear elliptic partial differential equations. In this paper we develop the form method for proving the conditions of Minty-Browder's theorem, as well as for obtaining the research results on the smoothness of the solutions. [ABSTRACT FROM AUTHOR]

The paper outlines the investigation of the linear elliptic equations on the whole Euclidean space R¹ ,l ⩾ 3 . We obtain some results on the existence and uniqueness of the solutions of these equations. [ABSTRACT FROM AUTHOR]

The paper under consideration is devoted to investigation of the second-order quasi-linear elliptic equations with slowly increasing coefficients on the euclidean space R¹, l ≥ 3. [ABSTRACT FROM AUTHOR]

This paper deals with the connection between elliptic equations with Gilbarg-Serrin matrix and the generalized parabolic problems. [ABSTRACT FROM AUTHOR]

The paper under consideration addresses the problem of studying the connection between elliptic equations with matrix of Gilbarg-Serrin and a generalized parabolic problem. [ABSTRACT FROM AUTHOR]

The present paper articulates the second-order quasilinear elliptic equations with slow increasing coefficients in the whole Euclidean space Rl , l ⩾ 3 . Furthermore, we deviate from the traditional point of view on the admissible class of the generalized solutions of the second-order elliptic equations, where the uniqueness theorem of Dirichlet problem is not exploited "in the small". Instead, we prove the probability of the solution of the elliptic equations with Gilbarg-Serrin matrix. [ABSTRACT FROM AUTHOR]

The work is devoted to investigation of the second-order quaisi-linear elliptic equations with slow-increasing coefficients on the Euclidean space R l , l ? 3. There, authors reject a traditional point of view at the admissible class of generalized solutions of the second-order elliptic equations in which the uniqueness theorem for Dirichlet problem "in the small" is not held. [ABSTRACT FROM AUTHOR]

The work is devoted to investigation of the second-order quasi-linear elliptic equations with slow-increasing coefficients on the Euclidean space R¹, 1 ≥ 3. The authors reject a traditional point of view at the admissible class of generalized solutions of the second-order elliptic equations in which the uniqueness theorem for Dirichlet problem "in the small" is not held. In the next part of the paper a nonlinear analogue of the Hille-Josida-Phillips theorem is proved in Lp(R¹,d¹x). [ABSTRACT FROM AUTHOR]

The equation was considered in numerous works of well-known mathematicians, as an example for which the uniqueness theorem for the Dirichlet problem ‘in the small’ is not held. The equation global solvability in R1 was established, proven theorem-analogue of the Minti-Brauder theorem was proved. [ABSTRACT FROM AUTHOR]