Wichita State University

About: Wichita State University is a education organization based out in Wichita, Kansas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 4988 authors who have published 9563 publications receiving 253824 citations. The organization is also known as: WSU & Fairmount College.

On the structure of spectra of periodic elliptic operators

Abstract: The paper discusses the problem of absolute continuity of spectra of periodic elliptic operators. A new result on absolute continuity for a matrix operator of Schrodinger type is obtained. It is shown that all types of operators for which the absolute continuity has previously been established can be reduced to this one. It is also discovered that some natural generalizations stumble upon an obstacle in the form of non-triviality of a certain analytic bundle on the two-dimensional torus.

Revealing nitrogen-containing species in commercial catalysts used for ammonia electrosynthesis

Abstract: Stimulated by the growing demand for sustainable and/or economical distributed ammonia synthesis, the electrochemical nitrogen reduction reaction has attracted considerable interest. The nitrogen-containing impurities in commercial metal-based nitrogen reduction reaction catalysts such as metal oxides and metallic irons have, however, been overlooked. Herein we report the presence of nitrogen-containing species in NOx− or nitrides at substantial levels revealed from many commercial catalysts. We call attention to the necessity to screen the NOx−/nitrides impurities in commercial catalysts, as the nitrogen impurities are not commonly listed in vendors’ assay documents. A simple two-step procedure (alkaline/acidic treatment followed by HPLC/UV–vis analysis) is recommended as a reliable protocol for screening NOx−/nitrides impurities in catalyst materials. A case analysis is also carried out on the previously reported H2O–NaOH–KOH system with both 15N-isotopic labelling and nitrogen elemental tracking, reassigning the true nitrogen source of the electrochemically produced NH3 from gaseous N2 to nitrogen-containing impurities in catalysts. The electrochemical nitrogen reduction reaction has recently attracted significant interest, but the true source of ammonia formation remains sometimes unclear. This Analysis reports a systematic investigation of the presence of nitrogen-containing species in a number of commercial catalysts, revealing substantial levels of NOx− and nitrides impurities for some of them.

Individual Characteristics and Creativity in the Marketing Classroom: Exploratory Insights:

Abstract: This study explores student characteristics that affect creativity skills. Students from three marketing classes were included in the study. Using the Torrance Tests of Creative Thinking, compariso...

Recent developments on the construction of spatio-temporal covariance models

Abstract: This paper briefly surveys some recent advances on how to construct spatio-temporal covariance functions, with the emphasis on the methods which can be used to derive covariance functions but not on a summary list of particular closed-form covariance functions. The advantages and shortcomings of some methods are discussed, and a number of proposals for future research are also suggested.