Results 61 to 70 of about 21,534 (315)

Geometric Properties of Partial Sums of Univalent Functions [PDF]

, 2012
The $n$th partial sum of an analytic function $f(z)=z+\sum_{k=2}^\infty a_k z^k$ is the polynomial $f_n(z):=z+\sum_{k=2}^n a_k z^k$. A survey of the univalence and other geometric properties of the $n$th partial sum of univalent functions as well as ...
Ravichandran, V.
core  

Emergence of Light‐Transforming Layered Hybrid Halide Perovskites

Advanced Functional Materials, EarlyView.
The emerging class of light‐transforming layered halide perovskite materials is reviewed, outlining challenges for their development and perspectives toward application in the future. Abstract Layered hybrid halide perovskites (LHPs) have attracted considerable attention in optoelectronics.
Ghewa AlSabeh, Jovana V. Milić
wiley   +1 more source

Some Subclasses of Univalent and Bi-Univalent Functions Related to K-Fibonacci Numbers and Modified Sigmoid Function

مجلة بغداد للعلوم, 2023
            This paper is interested in certain  subclasses of univalent and bi-univalent functions concerning  to shell- like curves connected with k-Fibonacci numbers involving modified Sigmoid activation function θ(t)=2/(1+e^(-t) ) ,t ≥0 in unit disk
Amal Madhi Rashid, Abdul Rahman S. Juma
doaj   +1 more source

Product of univalent functions [PDF]

Mathematical and Computer Modelling, 2013
Abstract Let S denote the class of functions f analytic and univalent in the unit disk | z | 1 normalized such that f ( 0 ) = 0 = f ′ ( 0 ) − 1 . In this article the authors discuss the radius of univalence of F ( z ) = g ( z ) h ( z ) / z when g and h belong ...
Obradović, Milutin, Ponnusamy, Saminathan   +1 more
openaire   +1 more source

Modelling Thermal Halide Exchange of Perovskite Powders With and Without BMIMBF4 From an Interdiffusion Perspective

Advanced Functional Materials, EarlyView.
Halide diffusion limits the stability of hybrid halide perovskites for optoelectronic applications and thus needs to be quantified. This study presents an effective interdiffusion model to obtain time‐dependent diffusion coefficients for I− and Br− diffusion from in situ X‐ray diffraction data during the formation of a solid solution MAPbIxBr3‐x from ...
Tobias Siegert, Prerna Pahwa, Markus Griesbach, Frank‐Julian Kahle, Harald Oberhofer, Anna Köhler, Helen Grüninger   +6 more
wiley   +1 more source

Magnetic‐Field Tuning of the Spin Dynamics in the Quasi‐2D Van der Waals Antiferromagnet CuCrP2S6

Advanced Functional Materials, EarlyView.
This study reveals 2D character of the spin dynamics in CuCrP2S6, as well as complex field dependence of collective excitations in the antiferromagnetically ordered state. Their remarkable tuning from the antiferromagnetic to the ferromagnetic type with magnetic field, together with the non‐degeneracy of the magnon gaps favorable for the induction of ...
Joyal John Abraham, Yaqian Guo, Yuliia Shemerliuk, Sebastian Selter, Saicharan Aswartham, Kranthi Kumar Bestha, Laura T. Corredor, Anja U. B. Wolter, Olga Kataeva, Luka Rogić, Noah Somun, Damjan Pelc, Oleg Janson, Jeroen van den Brink, Bernd Büchner, Vladislav Kataev, Alexey Alfonsov   +16 more
wiley   +1 more source

Enhancing the Photocatalytic Performance of Carbon Nitrides Through Controlled Local Structure Modification

Advanced Functional Materials, EarlyView.
This work utilizes poly(heptazine imides) as a model system to demonstrate how fine‐tuning the crystal structure influences the photocatalytic properties of layered carbon nitrides in the hydrogen evolution reaction. In particular, the nature of rotational defects and the hydration shell of cations are key contributors to enhanced hydrogen evolution ...
Diana V. Piankova, Hannes Zschiesche, Alexander P. Tyutyunnik, Erik Svensson Grape, Caio Vinícius C. R. da Silva, Walber G. Guimarães Junior, Andre. F. de Moura, Izadora F. Reis, Gabriel Ali A. Diab, José Balena G. Filho, Ivo F. Teixeira, Nadezda V. Tarakina   +11 more
wiley   +1 more source

On the definition of a close-to-convex function

International Journal of Mathematics and Mathematical Sciences, 1978
The standard definition of a close-to-convex function involves a complex numerical factor eiβ which is on occasion erroneously replaced by 1. While it is known to experts in the field that this replacement cannot be made without essentially changing the ...
A. W. Goodman, E. B. Saff
doaj   +1 more source

Ionic Control of Microstructure and Lubrication in Charged, Physically Cross‐Linked Hydrogels

Advanced Functional Materials, EarlyView.
Here, charged, physically cross‐linked poly(methacrylamide‐co‐methacrylic acid) hydrogels stabilized by a short‐range attractive, long‐range repulsive potential is investigated. This work uncovers how salt addition alters not only swelling, but also the microstructure and dynamics, near‐surface stiffness and charge, and ultimately, its lubricity. Salts
Alexander Deptula, Rosa M. Espinosa‐Marzal   +1 more
wiley   +1 more source

Self‐Assembled Membranes for High Ion Selectivity and Proton Blocking in Electrochemical Applications

Advanced Functional Materials, EarlyView.
Phase‐separated alkyl poly(vinylimidazolium) membranes exhibit exceptional ionic conductivity, counter‐ion selectivity, and proton‐blocking ability by forming stable micro/macrophase‐separated domains. This design overcomes the conductivity–selectivity trade‐off in conventional ion‐exchange membranes (IEMs), offering a new paradigm for high‐performance
Min Gyu Shin, José C. Díaz, Jovan Kamcev   +2 more
wiley   +1 more source