scholarly journals An equation to calculate internuclear distances of covalent, ionic and metallic lattices

2015 ◽  
Vol 17 (5) ◽  
pp. 3355-3369 ◽  
Author(s):  
Peter F. Lang ◽  
Barry C. Smith
Keyword(s):  
Metallic Structure ◽  
Ionic Radii ◽  
Internuclear Distances ◽  
Simple Equations

Simple equations calculating accurately internuclear distances of ionic (radii derived from metallic structure), covalent and metallic lattices are proposed.

Electronic polarizabilities, ionic radii, and repulsive potential parameters for diatomic alkali halide molecules

1980 ◽  
Vol 58 (7) ◽  
pp. 950-956 ◽  
Author(s):  
Jai Shanker ◽  
H. B. Agrawal
Keyword(s):  
Alkali Halide ◽  
Dipole Moments ◽  
Inverse Power ◽  
Exponential Dependence ◽  
Molecular Constants ◽  
Repulsive Potential ◽  
Ionic Radii ◽  
Internuclear Distances ◽  
Potential Parameters ◽  
Level Analysis

The electronic polarizabilities of ions in diatomic alkali halide molecules calculated using the Seitz–Ruffa energy level analysis are found to agree closely with those recently estimated by Brumer and Karplus utilizing the exchange perturbation theory. A sensible test of these polarizabilities has been presented by calculating the molecular properties like dipole moments. Ionic radii for alkali and halogen ions appropriate to diatomic molecules are determined using the relation between size and effective nuclear charges. The radii thus evaluated are found to be nearly additive and reproduce the internuclear distances within about ± 0.10 Å for all the alkali halide molecules except for RbF and CsF. An analysis of interaction energies in alkali halide molecules is presented by adopting two potential forms for the repulsive energy showing, respectively, the inverse power dependence and exponential dependence on internuclear distance. The additivity of repulsive potential parameters is discussed in the light of recent investigations. The results for the molecular constants obtained from the exponential form are in much better agreement with experiment than those estimated from the inverse power form.

Optimal Experimental Design With Nesting of Persons in Organizations

2013 ◽  
Vol 221 (3) ◽  
pp. 145-159 ◽  
Author(s):  
Gerard J. P. van Breukelen
Keyword(s):  
Repeated Measures ◽  
Optimal Number ◽  
Health Centers ◽  
Randomized Experiments ◽  
Optimal Sample ◽  
Treatment Conditions ◽  
Sampling Cost ◽  
Nested Designs ◽  
Simple Equations ◽  
Number Of Individuals

This paper introduces optimal design of randomized experiments where individuals are nested within organizations, such as schools, health centers, or companies. The focus is on nested designs with two levels (organization, individual) and two treatment conditions (treated, control), with treatment assignment to organizations, or to individuals within organizations. For each type of assignment, a multilevel model is first presented for the analysis of a quantitative dependent variable or outcome. Simple equations are then given for the optimal sample size per level (number of organizations, number of individuals) as a function of the sampling cost and outcome variance at each level, with realistic examples. Next, it is explained how the equations can be applied if the dependent variable is dichotomous, or if there are covariates in the model, or if the effects of two treatment factors are studied in a factorial nested design, or if the dependent variable is repeatedly measured. Designs with three levels of nesting and the optimal number of repeated measures are briefly discussed, and the paper ends with a short discussion of robust design.

scholarly journals Structure of Nanobody Nb23

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3567
Author(s):  
Mathias Percipalle ◽  
Yamanappa Hunashal ◽  
Jan Steyaert ◽  
Federico Fogolari ◽  
Gennaro Esposito
Keyword(s):  
Nmr Spectroscopy ◽  
Chemical Shift ◽  
Solution Structure ◽  
Chemical Shifts ◽  
Molecular Size ◽  
Side Chain ◽  
3D Nmr ◽  
Target Antigen ◽  
Internuclear Distances ◽  
2D And 3D

Background: Nanobodies, or VHHs, are derived from heavy chain-only antibodies (hcAbs) found in camelids. They overcome some of the inherent limitations of monoclonal antibodies (mAbs) and derivatives thereof, due to their smaller molecular size and higher stability, and thus present an alternative to mAbs for therapeutic use. Two nanobodies, Nb23 and Nb24, have been shown to similarly inhibit the self-aggregation of very amyloidogenic variants of β2-microglobulin. Here, the structure of Nb23 was modeled with the Chemical-Shift (CS)-Rosetta server using chemical shift assignments from nuclear magnetic resonance (NMR) spectroscopy experiments, and used as prior knowledge in PONDEROSA restrained modeling based on experimentally assessed internuclear distances. Further validation was comparatively obtained with the results of molecular dynamics trajectories calculated from the resulting best energy-minimized Nb23 conformers. Methods: 2D and 3D NMR spectroscopy experiments were carried out to determine the assignment of the backbone and side chain hydrogen, nitrogen and carbon resonances to extract chemical shifts and interproton separations for restrained modeling. Results: The solution structure of isolated Nb23 nanobody was determined. Conclusions: The structural analysis indicated that isolated Nb23 has a dynamic CDR3 loop distributed over different orientations with respect to Nb24, which could determine differences in target antigen affinity or complex lability.

scholarly journals On analysis of thermodynamic properties of cuboctahedral bi-metallic structure

2021 ◽  
Vol 44 (1) ◽  
pp. 117-128
Author(s):  
Muhammad Kamran Siddiqui ◽  
Yu-Ming Chu ◽  
Muhammad Nasir ◽  
Murat Cancan
Keyword(s):  
Thermodynamic Properties ◽  
Porous Materials ◽  
Gas Adsorption ◽  
Topological Indices ◽  
Metallic Structure

Abstract Porous materials, for example, metalnatural structures (MOFs) and their discrete partners metalnatural polyhedra (MOPs), that are built from coordinatively unsaturated inorganic hubs show incredible potential for application in gas adsorption/partition cycles, catalysis, and arising openings in hardware, optics, detecting, and biotechnology. A well-known hetero-bimetallic metalorganic polyhedra of this discrete partners metalnatural polyhedra (MOPs) class is cuboctahedral bi-metallic stricture. In this paper, we discuss the stricture of Hetero-bimetallic metalorganic polyhedra (cuboctahedral bi-metallic). Also, we computed the topological indices based on the degree of atoms in this cuboctahedral bi-metallic structure.

scholarly journals Simple Equations Pertaining to the Particle Number and Surface Area of Metallic, Polymeric, Lipidic and Vesicular Nanocarriers

2021 ◽  
Vol 89 (2) ◽  
pp. 15
Author(s):  
M. R. Mozafari ◽  
E. Mazaheri ◽  
K. Dormiani
Keyword(s):  
Drug Delivery ◽  
Surface Area ◽  
Particle Number ◽  
Analytical Techniques ◽  
Metallic Particles ◽  
Nutraceutical Compounds ◽  
Mathematical Formulas ◽  
Simple Equations

Introduction: Bioactive encapsulation and drug delivery systems have already found their way to the market as efficient therapeutics to combat infections, viral diseases and different types of cancer. The fields of food fortification, nutraceutical supplementation and cosmeceuticals have also been getting the benefit of encapsulation technologies. Aim: Successful formulation of such therapeutic and nutraceutical compounds requires thorough analysis and assessment of certain characteristics including particle number and surface area without the need to employ sophisticated analytical techniques. Solution: Here we present simple mathematical formulas and equations used in the research and development of drug delivery and controlled release systems employed for bioactive encapsulation and targeting the sites of infection and cancer in vitro and in vivo. Systems covered in this entry include lipidic vesicles, polymeric capsules, metallic particles as well as surfactant- and tocopherol-based micro- and nanocarriers.

scholarly journals Design of Wideband Bandpass Filter Based on Corrugated Disk Resonator with Multiple Resonant Modes

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2614
Author(s):  
Qian Yang ◽  
Shuangyang Liu ◽  
Hongyu Shi ◽  
Kai-Da Xu ◽  
Xinyue Dai ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Bandpass Filter ◽  
Design Method ◽  
Center Frequency ◽  
Localized Surface Plasmons ◽  
Metallic Structure ◽  
Disk Resonator ◽  
Resonant Frequencies ◽  
Resonant Modes ◽  
Via Holes

A corrugated disk resonator with eight grooves is proposed for wideband bandpass filter (BPF) design. Due to the spoof localized surface plasmons resonances of the corrugated metallic structure, the dipole, quadrupole, hexapole modes, and a fundamental mode excited by the introduced short-circuited via holes are employed to realize four transmission poles (TPs) in the passband. The theoretical analysis is described by the electric field and current distributions on the resonator. The resonant frequencies can be tuned easily by the parameters of the structure, which can be used to adjust the center frequency and bandwidth of the BPF freely. Furthermore, two resonators are cascaded to obtain eight TPs to improve the selectivity performance. Finally, three fabricated filters demonstrate the design method.

Simple equations method (SEsM) and its particular cases: Hirota method

2021 ◽  
Author(s):  
Nikolay K. Vitanov ◽  
Zlatinka I. Dimitrova
Keyword(s):  
Hirota Method ◽  
Simple Equations

scholarly journals Transport, functions, and interaction of calcium and manganese in plant organellar compartments

2021 ◽  
Author(s):  
Jie He ◽  
Nico Rössner ◽  
Minh T T Hoang ◽  
Santiago Alejandro ◽  
Edgar Peiter
Keyword(s):  
Molecular Mechanisms ◽  
Metal Tolerance ◽  
Essential Elements ◽  
Natural Resistance ◽  
Ionic Radii ◽  
Bivalent Cation ◽  
Cyclic Nucleotide Gated Channels ◽  
Complex Processes ◽  
Open Questions ◽  
Golgi Network

Abstract Calcium (Ca2+) and manganese (Mn2+) are essential elements for plants and have similar ionic radii and binding coordination. They are assigned specific functions within organelles, but share many transport mechanisms to cross organellar membranes. Despite their points of interaction, those elements are usually investigated and reviewed separately. This review takes them out of this isolation. It highlights our current mechanistic understanding and points to open questions of their functions, their transport, and their interplay in the endoplasmic reticulum (ER), vesicular compartments [Golgi apparatus, trans-Golgi Network (TGN), prevacuolar compartment (PVC)], vacuoles, chloroplasts, mitochondria, and peroxisomes. Complex processes demanding these cations, such as Mn2+-dependent glycosylation or systemic Ca2+ signaling, are covered in some detail if they have not been reviewed recently or if recent findings add to current models. The function of Ca2+ as signaling agent released from organelles into the cytosol and within the organelles themselves is a recurrent theme of this review, again keeping the interference by Mn2+ in mind. The involvement of organellar channels [e.g., Glutamate-Receptor-Likes (GLRs), Cyclic-Nucleotide-Gated Channels (CNGCs), Mitochondrial Conductivity Units (MCUs), Two-Pore Channel1 (TPC1)], transporters [e.g., Natural-Resistance-Associated Macrophage Proteins (NRAMPs), Calcium Exchangers (CAXs), Metal-Tolerance Proteins (MTPs), Bivalent-Cation Transporters (BICATs)] and pumps [Autoinhibited Ca2+-ATPases (ACAs), ER Ca2+-ATPases (ECAs)] in the import and export of organellar Ca2+ and Mn2+ is scrutinized, whereby current controversial issues are pointed out. Mechanisms in animals and yeast are taken into account where they may provide a blueprint for processes in plants, in particular with respect to tunable molecular mechanisms of Ca2+-versus-Mn2+ selectivity.

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