The Bakerian Lecture, 1981 Natural Selection of the Chemical elements

1981 ◽  
Vol 213 (1193) ◽  
pp. 361-397 ◽  
Keyword(s):  
Spatial Organization ◽  
Chemical Elements ◽  
Spatial Separation ◽  
Electronic Charge ◽  
Biological Chemistry ◽  
Protein Ligands ◽  
Atomic Properties ◽  
Functional Specification ◽  
Chemical Combination ◽  
Selection Of

Biochemistry is the study of an intricate interwoven ‘designed’ use of many elements in cells. It can only be fully appreciated in terms of the patterns of flow of chemicals, of ionic and electronic charge, and of energy directed in space. This requires a knowledge of the selection of the elements not only in analytical terms of uptake and chemical combination but also in terms of their spatial separation and functional specification. Starting from the abundance and availability of the elements an attempt is made here to analyse the roles of the elements, showing that much of the ‘chosen’ chemistry is an inevitable consequence of atomic properties. Selection has played upon this chemistry, extracting the utmost value from it, as seen in the refinement of functions of individual elements so that each element plays a quite separate and distinct role. Unique qualities dominate comparative similarities through the use of evolved specific small molecule and protein ligands. Proteins provide the evolu­tionary media for the development of function. It was the recognition and separation of each element in their specific sites (proteins) that allowed elements to be positioned in space. In turn the spatial organization generates, through feedback, the flow of other elements. Biological chemistry is only understandable in terms of the symbiotic use of some 25 elements and should not be related to so-called organic rather than to so-called inorganic chemistry.

scholarly journals Biogeochemical peculiarities of accumulation of chemical elements by plants of the Svydovets Massif of the Ukrainian Carpathians

2021 ◽  
Vol 30 (1) ◽  
pp. 78-89
Author(s):  
Nataliya O. Kryuchenko ◽  
Edward Ya. Zhovinsky ◽  
Petr S. Paparyga
Keyword(s):  
Chemical Elements ◽  
Total Concentration ◽  
Abies Alba ◽  
Herbaceous Plants ◽  
Silver Fir ◽  
Field Surveys ◽  
Vaccinium Myrtillus L ◽  
Bog Bilberry ◽  
Selection Of

he objective of the paper was determining biogeochemical peculiarities of ac- cumulation of chemical elements (Mn, Ni, Сo, V, Cr, Zr, Cu, Pb, Zn, Ba, P) by wild-grow- ing shrubs (stems and leaves) – bog bilberry (Vaccіnium uliginоsum), European blueberry (Vaccinium myrtillus L.), alpine juniper (J. communis subsp. alpina); perennial herbaceous plants (flowers and leaves) – common tormentil (Potentіlla erecta (L.) Hampe), willow gentian (Gentiana asclepiadea), true sedges (Carex); and trees (needles) of European silver fir (Abies alba) on nine plots in the Svy- dovets Massif of the Ukrainian Carpathians. The results we obtained based on field surveys (selection of samples of soil and vegeta- tion) and interpretation of their analysis allowed us to determine the total regional background of chemical elements in soils and ash of plants using emission spectral analysis. We assessed the total concentration of chemical elements in soils of the plots (least to highest): the Apshynets Ridge – the Herashaska Polonyna – Drahobratske Lake – the Svydovets stream – Apshynets Lake – Herashaske Lake – the Zhuravlyne Bog – Vorozheske Lake (group of small lakes) – Vorozheske Lake (large) and determined the dependence on type of soil and pH. We determined that for wild-growing herbaceous plants the biogeochemical activity of species increases in the following sequence: true sedges - willow gentian - common tormentil; for wild-growing shrubs (bog bilberry, European blueberry, alpine juniper) such a sequence is impossible to determine due to the great difference between the values on different plots. We determined the role of each plant as medicinal for treating microelement deficiency in Cu, Zn, Co. We determined that in the plot of the Herashaska Polonyna, the needles of alpine juniper contain a maximum amount of Zn and Co, the needles and leaves of bog bilberry – Cu, Zn, Co; the flowers and leaves of common tormentil by Apshynets Lake and European silver fir near the area of the Svydovets stream – Cu. We calculated the daily dose of each element according to species of plants to overcome microelementosis. The results of biogeochemical surveys may be the basis for determining and recommending plants as medicinal, and also of geochemical and biogeochemical monitoring studies.

HYPOTHESIS ON THE SYNERGISM OF RADIATION AND WATER FILTERS IN THE FORMATION OF BIOOBJECTS

2019 ◽  
Vol 21 (1) ◽  
pp. 53-58
Author(s):  
B.L. Oksengendler ◽  
S.E. Maksimov ◽  
S.U. Norbaev ◽  
L.Yu. Akopyan ◽  
M.V. Konoplyova ◽  
...  
Keyword(s):  
Periodic Table ◽  
Chemical Elements ◽  
Electron Shell ◽  
Living Matter ◽  
Heavy Atoms ◽  
The Third ◽  
Water Filters ◽  
Selection Of ◽  
Electron Shells

The article contains a hypothesis on the dominance of chemical elements of top periods of the Periodic Table in living matter. The idea is that the elements of the third and next periods of the table, in contrast to the first two periods, have larger number of subvalent electron shells. Because of this, ionization of the k-electron shell by radiation (kosmic and terrestrial) in the heavy atoms always leads to the Auger cascade, which causes the destruction of molecular chains. This mechanism can play a role of the radiation filter in the selection of light chemical elements in living matter in addition to the mechanism of hydrolytic filter (G.R. Ivanitskii).

Quantitative X-Ray Emission Analysis of Magnesium Through Fluorine with X-Ray and Electron Excitation

1966 ◽  
Vol 10 ◽  
pp. 494-505 ◽  
Author(s):  
F. Bernstein ◽  
R. A. Mattson
Keyword(s):  
Matrix Effects ◽  
Electron Excitation ◽  
Emission Analysis ◽  
X Ray ◽  
Excitation Potential ◽  
Chemical Combination ◽  
Elemental Sensitivity ◽  
Powder Samples ◽  
Sensitivity Changes ◽  
Selection Of

AbstractThe analysis of dry powder samples for magnesium, sodium, and fluorine by X-ray and electron excitation has been studied. As in the case of heavier elements, the form of chemical combination influences the elemental sensitivity; sensitivity changes due to self-absorption can be adequately predicted using published absorption coefficients. Where both absorption and enhancement effects are possible, selection of X-ray target or excitation potential can. eliminate the enhancement problem. Matrix effects were found to be extremely variable and unpredictable. Finally, X-ray and electron excitation results are compared for the three elements in a series of geological samples. Efficiency of excitation was far better for electron excitation, but limits of detectability were lower for X-ray excitation due to significantly lower backgrounds.

scholarly journals Metals and non-metals in the periodic table

2020 ◽  
Vol 378 (2180) ◽  
pp. 20200213
Author(s):  
Benzhen Yao ◽  
Vladimir L. Kuznetsov ◽  
Tiancun Xiao ◽  
Daniel R. Slocombe ◽  
C. N. R. Rao ◽  
...  
Keyword(s):  
Periodic Table ◽  
Chemical Elements ◽  
Quantum Mechanical ◽  
Great Success ◽  
Ambient Conditions ◽  
Theme Issue ◽  
Atomic Properties ◽  
System A ◽  
Mechanical Approach ◽  
Quantum Mechanical Approach

The demarcation of the chemical elements into metals and non-metals dates back to the dawn of Dmitri Mendeleev's construction of the periodic table; it still represents the cornerstone of our view of modern chemistry. In this contribution, a particular emphasis will be attached to the question ‘Why do the chemical elements of the periodic table exist either as metals or non-metals under ambient conditions?’ This is perhaps most apparent in the p-block of the periodic table where one sees an almost-diagonal line separating metals and non-metals. The first searching, quantum-mechanical considerations of this question were put forward by Hund in 1934. Interestingly, the very first discussion of the problem—in fact, a pre-quantum-mechanical approach—was made earlier, by Goldhammer in 1913 and Herzfeld in 1927. Their simple rationalization, in terms of atomic properties which confer metallic or non-metallic status to elements across the periodic table, leads to what is commonly called the Goldhammer–Herzfeld criterion for metallization. For a variety of undoubtedly complex reasons, the Goldhammer–Herzfeld theory lay dormant for close to half a century. However, since that time the criterion has been repeatedly applied, with great success, to many systems and materials exhibiting non-metal to metal transitions in order to predict, and understand, the precise conditions for metallization. Here, we review the application of Goldhammer–Herzfeld theory to the question of the metallic versus non-metallic status of chemical elements within the periodic system. A link between that theory and the work of Sir Nevill Mott on the metal-non-metal transition is also highlighted. The application of the ‘simple’, but highly effective Goldhammer–Herzfeld and Mott criteria, reveal when a chemical element of the periodic table will behave as a metal, and when it will behave as a non-metal. The success of these different, but converging approaches, lends weight to the idea of a simple, universal criterion for rationalizing the instantly-recognizable structure of the periodic table where … the metals are here, the non-metals are there … The challenge of the metallic and non-metallic states of oxides is also briefly introduced. This article is part of the theme issue ‘Mendeleev and the periodic table’.

The chemical composition of the sun1This review is part of a Special Issue on the 10th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas.

2011 ◽  
Vol 89 (4) ◽  
pp. 327-331 ◽  
Author(s):  
N. Grevesse ◽  
M. Asplund ◽  
A.J. Sauval ◽  
P. Scott
Keyword(s):  
Chemical Elements ◽  
Molecular Data ◽  
Solar Neighborhood ◽  
Spectral Lines ◽  
Oscillator Strengths ◽  
Atomic Data ◽  
Solar Photosphere ◽  
International Colloquium ◽  
Laboratory Plasmas ◽  
Selection Of

We have very recently re-determined the abundances of nearly all the available chemical elements in the solar photosphere, from lithium to thorium (Asplund et al. Annu. Rev. Astron. Astrophys. 47, 481 (2009)). This new complete and homogeneous analysis results from a very careful selection of spectral lines of all the indicators of the abundances present in the solar photospheric spectrum, from a discussion of the atomic and molecular data, and from an analysis of these lines based on a new 3D model of the solar outer layers, taking non-LTE effects into account when possible. We present these new results, compare them with other recent solar data as well as with recent results for the solar neighborhood, and discuss some of their most important implications as well as some of the atomic data we still urgently need.

scholarly journals Sustainability of spatially distributed bacteria-phage systems

2018 ◽  
Author(s):  
Rasmus Skytte Eriksen ◽  
Namiko Mitarai ◽  
Kim Sneppen
Keyword(s):  
Spatial Organization ◽  
Spatial Separation ◽  
The Self ◽  
Transient Dynamics ◽  
Large Reduction ◽  
Spatial Structures ◽  
Bacterial Survival ◽  
Spatially Distributed ◽  
Final Survival ◽  
Self Protection

AbstractVirulent phages can expose their bacterial hosts to devastating epidemics, in principle opening for a complete elimination of their hosts. Although experiments indeed confirm large reduction of susceptible bacteria, there is no reports of complete extinctions. We here address this phenomenon from the perspective of spatial organization of bacteria and how this can influence the final survival of them. By modeling the transient dynamics of bacteria and phages when they are introduced into an environment with finite resources, we quantify how the spatial separation of initial bacterial positions and the self-protection of bacteria growing in spherical colonies favor bacterial survival. This suggest that spatial structures on the millimeter scale plays an important role in maintaining microbial diversity.

scholarly journals Investigating the dynamics of microbial consortia in spatially structured environments

2020 ◽  
Author(s):  
Sonali Gupta ◽  
Tyler D. Ross ◽  
Marcella M. Gomez ◽  
Job L. Grant ◽  
Philip A. Romero ◽  
...  
Keyword(s):  
Gene Expression ◽  
Spatial Organization ◽  
Expression Patterns ◽  
Interaction Network ◽  
Spatial Separation ◽  
Microbial Consortia ◽  
Ecosystem Functions ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Microfluidic Platform

ABSTRACTThe spatial organization of microbial communities arises from a complex interplay of biotic and abiotic interactions and is a major determinant of ecosystem functions. We design a microfluidic platform to investigate how the spatial arrangement of microbes impacts gene expression and growth. We elucidate key biochemical parameters that dictate the mapping between spatial positioning and gene expression patterns. We show that distance can establish a low-pass filter to periodic inputs, and can enhance the fidelity of information processing. Positive and negative feedback can play disparate roles in the synchronization and robustness of a genetic oscillator distributed between two strains to spatial separation. Quantification of growth and metabolite release in an amino-acid auxotroph community demonstrates that the interaction network and stability of the community are highly sensitive to temporal perturbations and spatial arrangements. In sum, our microfluidic platform can quantify spatiotemporal parameters influencing diffusion-mediated interactions in microbial consortia.

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