elementary constituent
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2020 ◽  
Vol 844 ◽  
pp. 65-76
Author(s):  
Olena Svietkina ◽  
Kostiantyn Bas ◽  
Jamil Haddad ◽  
Kyrylo Ziborov ◽  
Valentyna Olishevska

It has been demonstrated that shock-vibrating activation of minerals is a prospective method to impact the ore; it may be used to intensify chemical and physical-chemical processes of mineral raw material processing and preparation. Differences in the composition and phase properties, obtained both in terms of continuous and periodic modes, are in the fact that in the first case loadings deal with interlayer space preserving layered nature of the mineral. When the mode is continuous, then the disturbances cover the octahedral layer though elementary constituent – tetrahedrons – are preserved. It has emerged that the most important advantage of high reacting capability of activated minerals is in the fact that leaching of some ores may be performed in chlorhydric acid at the expense of transformation of some silicate components into a specific state – loose packing of basic silicate chain. Consequently, shock-vibrating activation has become a basis to develop a method of leaching process intensification as well as a method to control phase formation.


Author(s):  
José Capmany ◽  
Daniel Pérez

Programmable integrated photonics (PIP) relies on designing suitable basic building blocks (BBBs) able to carry elementary signal processing operations and interconnection hardware architectures that offer very high spatial regularity. The most popular BBBs proposed so far are based on elementary 2×2 tunable photonics coupling components capable of providing independent setting of the power coupling ratio. Additionally, they are based on the phase shift experienced by the incoming signals from two input waveguides in their transition to the two output waveguide ports of the device. This chapter deals primarily with these components. First, it considers the basic matrix methods required to describe their operation, either standalone or in combination with others to form more complex structures. Next, it describes the main technology approaches for the implementation of BBBs, including 3dB Mach–Zehnder tunable couplers, directional couplers, and beamsplitters, followed by how these BBBs are employed to build up a tunable basic unit (TBU), which is the elementary constituent of waveguide mesh circuits. It concludes by describing the devices and techniques relevant in multiport devices, and discusses the equivalence between mode conversion and linear optics matrix transformations and the universal linear combiner.


Vox Patrum ◽  
2015 ◽  
Vol 63 ◽  
pp. 77-93
Author(s):  
Mariusz Szram

The article expounds on the groundwork laid by the first Latin treaty De haeresibus by Philastrius, the fourth-century bishop of Brescia, analyzed on the background of writings of Irenaeus, Tertullian and Origen, how the rooted in Gnosticism representatives of early Christian heresies (Carpocratians, Saturninus, Valentinus, Apelles, Marcion, Manicheans) have comprehended the genesis of man’s body. After a general delivery of early Christian doubts regarding the value of human flesh, different varieties of heretical paradox – ensuing from Platonic and Gnostic cosmo-anthropological tendencies – are presented. The paradox could be formulated in the following manner: human body of the first man Adam – and correspondingly all of his descendants – is genetically and ontologically evil as being an elementary constituent of the material world. Hence the flesh of a new Adam, i.e. Christ, must come form another realm and be free of the earthly materiality in order to be good by nature and worthy of Saviour’s person. The presented mode of thinking instigated the rise of theological misconceptions, in particular the eschatological ones denying human body the possibility of resurrec­tion and recognizing – in a Gnostic fashion – the liberation of man from flesh, not his salvation alongside his body.


2011 ◽  
Vol 1301 ◽  
Author(s):  
Thomas K. Bader ◽  
K. Hofstetter ◽  
Ch. Hellmich ◽  
Josef Eberhardsteiner

ABSTRACTWood strength is highly anisotropic, due to the inherent structural hierarchy of the material. In the framework of a combined random-periodic multiscale poro-micromechanics model, we here translate compositional information throughout this hierarchy into the resulting anisotropic strength at the softwood level, based on “universal” elastic properties of cellulose, hemicelluloses, and lignin, and on the shear strength of the latter elementary constituent. Therefore, derivation of the elastic energy in a piece (representative volume element – RVE) of softwood, stemming from homogeneous macroscopic strains prescribed in terms of displacements at the boundary of the RVE and from pressure exerted by water filling the nanoporous space between the hemicelluloses-lignin network within the cell walls, with respect to the shear stiffness of lignin, yields higher order strains in the lignin phase, approximating micro-stress peaks leading to local lignin failure. Relating this (quasi-brittle) failure to overall softwood failure (or strictly speaking, elastic limit of softwood) results in a macroscopic microstructure-dependent failure criterion for softwood. The latter satisfactorily predicts the biaxial strength of spruce at various loading angles with respect to the grain direction. The model also predicts the experimentally well-established fact that uniaxial tensile and compressive strengths, as well as the shear strength of wood, depend quasi-linearly on the cell water content, but highly nonlinearly on the lumen porosity.


Author(s):  
Masataka Fukunaga ◽  
Nobuyuki Shimizu

Two types of models are proposed for describing nonlinear fractional derivative dynamical behavior of viscoelastic materials subject to impulse forces. The models are derived based on the thermodynamic elasticity in terms of entropy and on the “scale-free response of the material” under the basic assumption that the viscoelastic materials consist of stable coils of polymers, which we refer to as blobs. The blobs, which may be connected to each other by chemical bonds or physical bonds, are considered here as the elementary constituent of viscoelastic materials from which the nonlinear fractional derivative models are derived. Responses of individual blobs can determine the net collective response of the viscoelastic material to impulse forces. From the above consideration, two types of models are proposed in which the force elements or the stress elements are connected by the generalized Maxwell law.


1862 ◽  
Vol 152 ◽  
pp. 167-183 ◽  

The substitution of a compound organic radical for an elementary constituent in inorganic compounds has proved itself to be one of the most important and fertile fields of modern chemical investigation. The application of this species of substitution to the inorganic compounds of metals has called into existence an entirely new and extensive family of organic substances— the organo-metallic compounds, bodies never met with in nature, distinguished by their well-marked affinities, and capable in some instances of effecting, in their turn, numerous substitutions of a like character. The realization of a similar substitution in the case of certain inorganic compounds of nitrogen and phosphorus has, in the hands of Hofmann, not only enriched the science with a host of new and interesting compounds, but has also brought our knowledge of the organic bases to a degree of completeness, which cannot be rivalled in any other class of organic compounds. Lastly, attempts have not been wanting to extend these reactions to the oxygen com­pounds of the metalloids; and although this portion of the field presents difficulties of a somewhat more formidable character, yet these attempts have not unfrequently been attended with success. Thus nitric oxide has been transformed into dinitroethylic and dinitromethylic acids; sulphurous anhydride into ethylodithionic and methylotri-thionic acids; and carbonic anhydride into propionic and acetic acids. The last-named reaction, confirming, as it did, the view previously expressed by Kolbe and myself, that organic compounds in general are nothing more than substitutions of this nature effected in carbonic oxide, in carbonic acid, and possibly in other inorganic compounds of carbon, naturally awakened a desire to extend this inquiry to the oxygen compounds of boron and silicon, which are usually regarded as possessing certain im­portant analogies with carbonic anhydride. With this end in view, boracic ether was submitted to the action of zincethyl by Mr. Duppa and myself. W e found that the whole of the oxygen in boracic acid became replaced by ethyl, and in a short communi­cation to the Royal Society, we described some of the properties of the remarkable body, boric ethide, thus formed. In the further study of this substance, and the extenion of the research to the homologous methyl compound, I much regret having been deprived of the cooperation of my friend and fellow-labourer who had rendered me such valuable assistance at the commencement of the investigation, but who was reluctantly compelled to abandon its further prosecution.


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