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Macro-evolution

Zhou et al. obtained nitrogen-doped titanium dioxide replicas via a two-step infiltration process with natural leaves as templates [220]. The replicas inherited the hierarchical structures of the natural leaf at the macro-, micro-, and nanoscales. These materials showed enhanced light-harvesting and photocatalytic hydrogen evolution activities. The photocatalytic water splitting activity of the artificial leaf structures was eight times higher than that of titanium dioxide synthesized without templates. [Pg.116]

From the results reported to date, it seems that the manner in which haptens are attached to carrier proteins leads to significant differences in certain cases. Clearly, haptens designed with aromatic moieties between the linkage to the immunogenic carrier protein and the TSA motif often have better antibody recognition. Recently, Hilvert pointed out that on both micro and macro levels, mechanistic improvements arise as a function of time. The differences in time scales for the evolution of natural enzymes and antibodies — millions of years versus weeks or months — also appear to be an explanation of the low efficiency of antibody catalysts. He also highlighted that the unique immunoglobulin fold has not been adopted by nature as one of the common scaffolds on which to build enzyme catalytic machinery. Therefore, antibody structure itself places limitations on the kind of reactions amenable to catalysis. [Pg.336]

The MFCs for a species are coefficients for real trends of plant traits during the period studied. Numerically, it can have a value from 0.00 to 1.00 and can also be interpreted, if needed, as a percentage. The lower the MFC, the weaker the rate of micro-evolution for the period of time studied. A maximum value (1.00) for the MFC signifies that a micro-evolution (trait change) has occurred in all the plants studied and, therefore, macro-evolution has occurred in the population. In this case, the new hypothetical constant coefficient is valid (no trends, no mutations, no trajectories). The MFCs can be positive or negative. Positive MFCs show that the traits are developing in a micro-evolutionary process, and negative MFCs indicate the reverse. The MFCs represent very useful parameters for measurement of micro-evolution in plant species. [Pg.218]

Let us try and understand this. As stated, Ni plating baths (as well as other acidic baths such as those of Cu and Zn) show poor throwing power. This is so because their CE values are =100% at the low and high current density values, and so macroscopic irregularities on a cathode will lead to nonuniform deposits. Alkaline baths, on the other hand, have a better macro throwing power. This is the case since, in order to remain in solution in such a bath, the metal ion, to be deposited, must be present in complex ions. These ions, in turn, encounter high concentration polarization. Also, in most complex baths the deposition potentials are amenable to hydrogen evolution, which competes with metal deposition such that CE falls as current density is increased. That kind of behavior results in a more uniform deposit on... [Pg.201]

With the exception of micro-organisms, the cells then and now are not the same they are separated by 3 billion years of genomic refinement. This genomic evolution, the development of the complexity that led to macro-organisms, was driven by the thermodynamics of DNA/RNA chemistry towards an equilibrium point which was stable enough to persist. [Pg.58]

The concept of entropy and its dependence on randomness, led to the interpretation of thermodynamic properties in terms of atomic or molecular arrangements. Earlier also, there were attempts to correlate, rather logically, the temperature with molecular motion. But till the evolution of entropy concept, thermodynamics studied properties of system at macro-level only. The latter interpretations with atomic and molecular arrangements came to be discussed under Statistical Thermodynamics. ... [Pg.17]

The contributions of Vulpiani s group and of Kaneko deal with reactions at the macroscopic level. The contribution of Vulpiani s group discusses asymptotic analyses to macroscopic reactions involving flows, by presenting the mechanism of front formation in reactive systems. The contribution of Kaneko deals with the network of reactions within a cell, and it discusses the possibility of evolution and differentiation in terms of that network. In particular, he points out that molecules that exist only in small numbers can play the role of a switch in the network, and that these molecules control evolutionary processes of the network. This point demonstrates a limitation of the conventional statistical quantities such as density, which are obtained by coarse-graining microscopic quantities. In other words, new concepts will be required which go beyond the hierarchy in the levels of description such as micro and macro. [Pg.561]

These studies have all shown the importance of hybrid technology. Antibodies have been used to elucidate the architecture of viruses and to identify receptor-binding regions. They have directly addressed the mechanism of antibody-mediated neutralization, which has greatly impacted the development of vaccines. Finally, they have improved our understanding about the forces that have driven the evolution of viral structure. It is likely that such studies will continue to help us understand the architecture of macro-macromolecular complexes and the dynamics of these viral capsids. [Pg.442]

This model is based on quasimolecular dynamics, in which the medium is assumed to be composed of an assembly of meso-scale discrete particles (i.e., finite elements). Tlie movement and deformation of the material system and its evolution are described by the aggregate movements of these elements. Two types of basic characteristics, geometrical and physical, are considered. In tlie geometrical aspect, sliapes and sizes of elements and tlie manner of their initial aggregation and arrangement are the important factors. In the physical aspect, mechanical, physical, and chemical characteristics, such as the interaction potential, phase transition, and chemical reactivity may be tlie important ones. To construct this model, many physical factors, including interaction potential, friction of particles, shear resistance force, energy dissipation and temperature increase, stress and strain at the meso- and macro-levels, phase transition, and chemical reaction are considered. In fact, simulation of chemical reactions is one of the most difficult tasks, but it is the most important aspect in shock-wave chemistiy. [Pg.216]


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