Shell filling

Gelbkreuz-geschoss, n. (MU.) "yellow cross projectile or shdl. -kampfstoff, -stoff, m. yellow cross shell filling (mustard gas or other vesicant). [Pg.177]

Granat-fullung, /. shell filling, -gestein, n. garnet rock. [Pg.193]

Only if shells filled sequentially, which they do not, would the theoretical relationship between the quantum numbers provide a purely deductive explanation of the periodic system. The fact the 4s orbital fills in preference to the 3d orbitals is not predicted in general for the transition metals but only rationalized on a case by case basis as I have argued. Again, I would like to stress that whether or not more elaborate calculations finally succeed in justifying the experimentally observed ground state does not fundamentally alter the overall situation.12... [Pg.100]

The proposed new table retains most of the feature of the Janet left-step table but does not commit one to placing helium in the alkaline earths. The regular form of the table represents an advantage over the medium-long form and the closer connection with electron-shell filling that the left-step table offers is maintained with the small disadvantage that two values of n + i, namely I and 2, appear in the same first row. [Pg.122]

The new proposed version does not alleviate the concern that some authors voice in wanting to maintain the metals on the left and non-metals on the right of the table. We suggest that such a desideratum does not necessarily reflect the most fundamental aspects of the elements as basic substances whereas the left-step and its new variant do. The latter two forms aim to represent elements as basic substances as well as establishing a closer connection with fundamental aspects of electron-shell filling, and consequently with quantum mechanics, than the medium-long form table does. Finally, we have recently published another new table that differs only in shape from the one proposed here (10). [Pg.122]

ABSTRACT This article concerns various foundational aspects of the periodic system of the elements. These issues include the dual nature of the concept of an "element" to include element as a "basic substance" and as a "simple substance." We will discuss the question of whether there is an optimal form of the periodic table, including whether the left-step table fulfils this role. We will also discuss the derivation or explanation of the [n + , n] or Madelung rule for electron-shell filling and whether indeed it is important to attempt to derive this rule from first principles. In particular, we examine the views of two chemists, Henry Bent and Eugen Schwarz, who have independently addressed many of these issues. 2008 Wiley Periodicals, Inc. Int J Quantum Chem 109 959-971, 2009... [Pg.131]

Currently, breast cancer is the most frequently diagnosed cancer in both white and African-American women. According to latest reports, of the 662,870 cancer cases reported for women in 2005, 32% were breast cancer. The incidence of breast cancer increased from 1 in 20 in 1960 to 1 in 8 today. More than 100,000 women per year require mastectomy for treatment, and every year 75% decide to have reconstmction. About half the number of these women select prostheses made of silica-reinforced silicone-rubber shell filled with silicone gel, while the other half have the same shell filled with physiological saline. Reportedly, gel-fiUed prostheses feel more natural, but are associated with true or perceived health problems and remain highly controversial. [Pg.199]

EXAMPLE 3.10. (a) How many electrons could fit in the first seven shells of an atom if the shells filled to their capacity in numeric order (b) Why does this not happen ... [Pg.50]

The Group II elements each have two electrons in their outer energy shells, and the larger ones have an empty shell deep inside them. The transition series added electrons to the inner shell until it was completely filled. So, these last three transition elements are like Group II in construction, with the inner shell filled instead of empty, and two electrons in the outer shell. Those elements with filled shells and those with empty ones are the most stable. [Pg.59]

Chandler, R. E. Houtepen, A. J. Nelson, J. Vanmaekelbergh D. 2007. Electron transport in quantum dot solids Monte Carlo simulations of the effects of shell filling, Coulomb repulsions, and site disorder. Phys. Rev. B 75 085325-085335. [Pg.344]

Laboratory procedures are presented for two divergent approaches to covalent structure controlled dendrimer clusters or more specifically - core-shell tecto(dendrimers). The first method, namely (1) the self assembly/covalent bond formation method produces structure controlled saturated shell products (see Scheme 1). The second route, referred to as (2) direct covalent bond formation method , yields partial filled shell structures, as illustrated in Scheme 2. In each case, relatively monodispersed products are obtained. The first method yields precise shell saturated structures [31, 32] whereas the second method gives semi-controlled partially shell filled products [30, 33],... [Pg.619]

Figure 27.2 (a) Symmetry properties for core-shell structures where r,/r2 < 1.20 (b) sterically induced stoichiometry (SIS) based on respective radii (r,) and (r2) core and shell dendrimers respectively (c) Mansfield-Tomalia-Rakesh equation for calculation of maximum shell filling when r,/r2 < 1.20... [Pg.620]

The second method referred to as the direct covalent bond formation method , produces semi-controlled, partial shell filled structures. It involves the reaction of a limited amount of nucleophilic dendrimer core reagent with an excess of... [Pg.624]

Scheme 2 Reaction scheme for partial shell filled model, step (A) step (B) describes surface capping reactions...

Molecular weights for the final products were determined by MALDI-TOF-MS or (polyacrylamide) gel electrophoresis (PAGE). They were corroborated by calculated values from AFM dimension data and were found to be in relatively good agreement within this series (Table 27.2). Calculations based on these experimentally determined molecular weights allowed the estimation of shell filling levels for respective core-shell structures within this series. A comparison with mathematically predicted shell saturated values reported earlier [34], indicates these core-shell structures are only partially filled (i.e. 40-66% of fully saturated shell values, see Table 27.2). [Pg.626]

Although this method is essentially restricted to a particular sub-set of lattice stabilities, it nevertheless provides an additional experimental input, especially in cases where it is not possible to access the metastable phase by other methods. It is therefore disappointing that there are no experimental values of the SEE available for Ru or Os, which could provide confirmation of G p obtained by other methods. High SEE values have, however, been both observed and predicted for Rh and Ir, which is indirect confirmation for a larger variation of g " p with (/-shell filling than proposed by Kaufinan and Bernstein (1970). [Pg.158]

By the time Bohr turned his attention to the problem, significant advances had been made. Physicists working with the old quantum theory had developed a number of rules about the manner in which electrons interacted with one another. Bohr realized that these rules could be used to confirm Kossel s hypothesis and to make informed guesses about the atomic structure of the elements. For example, hydrogen has one electron, placed in the innermost shell. Helium, having two electrons, has this shell filled up. Thus lithium, the third element, has to have two electrons in an inner shell and one with an... [Pg.191]

To summarize this subsection one can state that i) The role of second-order shell-effect terms can be determined by investigating the discrepancies between the discrete second derivatives of the functions 8E (Z) and 8 Ehfr(Z,Y(,). ii) For the second row of elements these terms determine the whole pattern of the oscillating part of the energy iii) They also play an important role in critical regions of shell filling (i.e., around shells fully, half, or irregularly filled). [Pg.71]

The variation of 6E and 6iE as a function of the atomic number Z manifests the saw-tooth pattern, well-known in atomic nuclei and metal clusters [13]- [15], having sharp minima at atoms with filled or half-filled shells in accordance with the shell-filling process. [Pg.160]

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