scholarly journals Heavy metals as indicators of dynamics of the circulation of substances on recultivated lands of the Western Donbass

2018 ◽  
Vol 47 ◽  
pp. 69-74
Author(s):  
V. M. Zverkovsky ◽  
M. V. Shamray
Keyword(s):  
Normal Development ◽  
Physicochemical Characteristics ◽  
Donets Basin ◽  
Biological Cycle ◽  
Variation Range ◽  
Ground Types ◽  
Growing Conditions ◽  
Forest Rehabilitation ◽  
Copper Lead ◽  
Wide Variation Range

The biological cycle of matter in artificial plantations of forest rehabilitation sites of the Western Donets Basin was studied. The content and patterns of microelements’ migration in plants, tree waste, litter and soils are determined. Manganese, copper, lead, chromium, nickel and titanium were under investigation. The dependence between the microelements content in tree waste, litter and soil and their main physicochemical characteristics as well as the correspondence of forest growing conditions to the optimal limits of the elements’ content in soil for plants normal development are characterized. The factors influencing the trace elements content in the fill-up reclaiming layer are analyzed. The reasons for the wide variation range of the microelements content in the leaves of experimental trees, and the possibility of using different ground types and plantation patterns are explained. It makes possible to estimate the importance of the biological stage of rehabilitation for the preventing technogenic influence on the environment.

scholarly journals PHYSICAL AND COMPOSITIONAL CHARACTERISTICS OF CHESTNUT FRUITS

2020 ◽  
Vol 1 (1) ◽  
pp. 51-58
Author(s):  
Sina Cosmulescu ◽  
Ion Trandafir ◽  
Violeta Nour ◽  
Mihai Botu
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
High Variability ◽  
Fresh Matter ◽  
Primary And Secondary Metabolites ◽  
Positive Effects ◽  
Variation Range ◽  
The Individual ◽  
Physical And Chemical ◽  
Wide Variation Range

The objective of this study was investigationofphysical and compositional fruits characteristics of six chestnut cultivars. The fruits belonging to these cultivars were subjected to physical and chemical composition determinations, and the obtained results were comparatively analysed. It can be noticed that there are significant differences between cultivars for all the analysed traits. A high variability was found between cultivars in terms of nutrients content. The moisture content of chestnuts analysed in this study ranged from 51.63% to 58.42%. The protein content recorded values between 5.40 and 7.18% fresh matter. The polyphenols content in cultivars taken under analysis was between 1.65 and 19.60 mg GAE/g, which is a very large variation range between different cultivars. The obtained values of antioxidant activity of chestnuts are high, ranging from 0.73 to 9.90 mg Trolox/g of fresh substance, revealing also a wide variation range. Among the individual phenolic compounds, elagic and gallic acids were determined in higher amounts. The results of this study have shown that chestnut fruits contain significant concentrations of primary and secondary metabolites that are known for their positive effects on human health.

scholarly journals Physicochemical characteristics of seeds from wild and cultivated castor bean plants (Ricinus communis L.)

2018 ◽  
Vol 38 (1) ◽  
pp. 24-30
Author(s):  
Jose Daniel Mosquera ◽  
Jose Fernando Vasco-Leal ◽  
Ismael Hernandez-Rios ◽  
Santiago De Jesus Mendez-Gallegos ◽  
Maria De Jesus Perea-Flores ◽  
...  
Keyword(s):  
Ricinus Communis ◽  
Chemical Properties ◽  
Physicochemical Characteristics ◽  
Industrial Sector ◽  
Low Fertility ◽  
Ricinus Communis L ◽  
Growing Conditions ◽  
Castor Seeds ◽  
Physical And Chemical

The castor (Ricinus communis L.) is an oilseed plant whose main features are its drought resistance, and its adaptation to eroded, polluted, and low fertility soils. Its oil has a great demand in the industrial sector and it has recently attracted considerable interest for its use in the production of biodiesel and jet fuel. In this study, morphological, physical and chemical characterizations were performed to ascertain the quality of wild (VQ-1) and under cultivation (VQ-7) oil castor seeds. The results showed that there are differences in the morphological and physicochemical characteristics regarding oil content (44,95 vs 33,84%), ash (3,20 vs 2,42%), and 100-seed-weight (45,87 vs 54,23g); similar behavior was recorded when characterizing the oil: kinematic viscosity (269,67 vs 266,44mm2 /s), density (0,9389 vs 0,9465g/cm3 ), and acidity index (0,9918 vs 0,5440mg KOH/g) for VQ-1 and VQ-7, respectively. Growing conditions to which castor plants were subjected may influence both the final quality of seeds and chemical properties of the oil.

Hypersonic Cruise Vehicle Attitude Control Based on NESO

2013 ◽  
Vol 427-429 ◽  
pp. 913-920
Author(s):  
Cheng Bin Lian ◽  
Chen Bai ◽  
Zhang Ren ◽  
Xing Yue Shao
Keyword(s):  
Attitude Control ◽  
Backstepping Method ◽  
Attitude Control System ◽  
First Order ◽  
Signal Correction ◽  
Variation Range ◽  
Aerodynamic Parameters ◽  
Backstepping Controller ◽  
Nonlinear Extended State Observer ◽  
Wide Variation Range

Hypersonic cruise vehicles traverse abroad flight envelope, severe interference and aerodynamic parameters of great uncertainty. Aiming at these problems, the attitude control system is divided into two first-order subsystem based on the backstepping, which improved by introducing the command filter and the error signal correction. simplifies the solution of pseudo control of derivative, and considering the attenuation and noise on the system state. The aerodynamic parameters wide variation range and disturbances were classified into two subsystems uncertainties, and two sets of nonlinear extended state observer (NESO) were used to estimate them. The backstepping controller based on NESO was designed with combined estimated value and backstepping method. Additionally used fuzzy logic to tuning the NESO parameters. Simulation results show that the method can track the control signal accurately, and has good robustness against parameter uncertainty.

Electron Microscopy of Silicon Deposits in Foliar Idioblasts of Magnolia Grandiflora

1976 ◽  
Vol 34 ◽  
pp. 374-375
Author(s):  
Michael T. Postek
Keyword(s):  
Electron Microscopy ◽  
Water Loss ◽  
Normal Development ◽  
Magnolia Grandiflora ◽  
Plant Body ◽  
Normal Metabolism ◽  
Hydrated Oxide

Silicon occurs naturally in plants in the form of its hydrated oxide (SiO2.nH2O) commonly called silica. Silica has been shown to be a necessary element in the normal development of many plants, playing an array of roles including strengthening, protection, and reduction of water loss. Deposition of silica in various portions of the plant body, especially the leaves, may also be viewed as a way for the plant to dispose of any excess silica taken up beyond that necessary for normal metabolism.Studies of this “opaline” silica have thus far been limited to species of the Cyperaceae and Gramineae known to possess significant quantities of silica. Within the Magnoliaceae, certain “glistening” idioblast cells at the foliar veinlet termini and vein sheaths of Magnolia grandiflora (1) have been suspected to be siliceous in nature.

Applications of SEM/EDXA in cement clinker investigation

1990 ◽  
Vol 48 (4) ◽  
pp. 870-871
Author(s):  
Arezki Tagnit-Hamou ◽  
Shondeep L. Sarkar
Keyword(s):  
Mineralogical Composition ◽  
Physicochemical Characteristics ◽  
Cement Clinker ◽  
Accurate Information ◽  
Phase Identification ◽  
History Of ◽  
Bulk Chemical ◽  
Resolution Imaging ◽  
Proven Method ◽  
Instantaneous Chemical

All the desired properties of cement primarily depend on the physicochemical characteristics of clinker from which the cement is produced. The mineralogical composition of the clinker forms the most important parameter influencing these properties.Optical microscopy provides reasonably accurate information pertaining to the thermal history of the clinker, while XRDA still remains the proven method of phase identification, and bulk chemical composition of the clinker can be readily obtained from XRFA. Nevertheless, all these microanalytical techniques are somewhat limited in their applications, and SEM/EDXA combination fills this gap uniquely by virtue of its high resolution imaging capability and possibility of instantaneous chemical analysis of individual phases.Inhomogeneities and impurities in the raw meal, influence of kiln conditions such as sintering and cooling rate being directly related to the microstructure can be effectively determined by SEM/EDXA. In addition, several physical characteristics of cement, such as rhcology, grindability and hydraulicity also depend on the clinker microstructure.

Localization of Intracisternal a Particle Antigens in Neoplastic Cells and Preimplantation Mouse Embryos

1980 ◽  
Vol 38 ◽  
pp. 696-697
Author(s):  
Thomas T.F. Huang ◽  
Patricia G. Calarco
Keyword(s):  
Endoplasmic Reticulum ◽  
Normal Development ◽  
Mouse Embryos ◽  
Neoplastic Cells ◽  
Large Numbers ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Intracisternal A Particle ◽  
Normal Feature

The stage specific appearance of a retravirus, termed the Intracisternal A particle (IAP) is a normal feature of early preimplantation development. To date, all feral and laboratory strains of Mus musculus and even Asian species such as Mus cervicolor and Mus pahari express the particles during the 2-8 cell stages. IAP form by budding into the endoplasmic reticulum and appear singly or as groups of donut-shaped particles within the cisternae (fig. 1). IAP are also produced in large numbers in several neoplastic cells such as certain plasmacytomas and rhabdomyosarcomas. The role of IAP, either in normal development or in neoplastic behavior, is unknown.

Common modifications of selenocysteine in selenoproteins

2019 ◽  
Vol 64 (1) ◽  
pp. 45-53 ◽  
Author(s):  
Elias S.J. Arnér
Keyword(s):  
Amino Acids ◽  
Covalent Binding ◽  
Physicochemical Characteristics ◽  
Redox Active

Abstract Selenocysteine (Sec), the sulfur-to-selenium substituted variant of cysteine (Cys), is the defining entity of selenoproteins. These are naturally expressed in many diverse organisms and constitute a unique class of proteins. As a result of the physicochemical characteristics of selenium when compared with sulfur, Sec is typically more reactive than Cys while participating in similar reactions, and there are also some qualitative differences in the reactivities between the two amino acids. This minireview discusses the types of modifications of Sec in selenoproteins that have thus far been experimentally validated. These modifications include direct covalent binding through the Se atom of Sec to other chalcogen atoms (S, O and Se) as present in redox active molecular motifs, derivatization of Sec via the direct covalent binding to non-chalcogen elements (Ni, Mb, N, Au and C), and the loss of Se from Sec resulting in formation of dehydroalanine. To understand the nature of these Sec modifications is crucial for an understanding of selenoprotein reactivities in biological, physiological and pathophysiological contexts.

Lexical Comprehension in Young Children With Developmental Delays

1994 ◽  
Vol 3 (1) ◽  
pp. 79-88 ◽  
Author(s):  
Theresa A. Kouri
Keyword(s):  
Young Children ◽  
Developmental Delays ◽  
Normal Development ◽  
Clinical Applications ◽  
Group Status ◽  
Novel Object ◽  
Related Information ◽  
Comprehension Skills ◽  
Lexical Items ◽  
Lexical Concepts

Lexical comprehension skills were examined in 20 young children (aged 28–45 months) with developmental delays (DD) and 20 children (aged 19–34 months) with normal development (ND). Each was assigned to either a story-like script condition or a simple ostensive labeling condition in which the names of three novel object and action items were presented over two experimental sessions. During the experimental sessions, receptive knowledge of the lexical items was assessed through a series of target and generalization probes. Results indicated that all children, irrespective of group status, acquired more lexical concepts in the ostensive labeling condition than in the story narrative condition. Overall, both groups acquired more object than action words, although subjects with ND comprehended more action words than subjects with DD. More target than generalization items were also comprehended by both groups. It is concluded that young children’s comprehension of new lexical concepts is facilitated more by a context in which simple ostensive labels accompany the presentation of specific objects and actions than one in which objects and actions are surrounded by thematic and event-related information. Various clinical applications focusing on the lexical training of young children with DD are discussed.

Sign in / Sign up

Export Citation Format

Share Document