Fractional differentiability for a class of double phase problems with measure data

Author(s):  
Sun-Sig Byun ◽  
Pilsoo Shin ◽  
Kyeong Song
Author(s):  
P.A. Crozier ◽  
M. Pan

Heterogeneous catalysts can be of varying complexity ranging from single or double phase systems to complicated mixtures of metals and oxides with additives to help promote chemical reactions, extend the life of the catalysts, prevent poisoning etc. Although catalysis occurs on the surface of most systems, detailed descriptions of the microstructure and chemistry of catalysts can be helpful for developing an understanding of the mechanism by which a catalyst facilitates a reaction. Recent years have seen continued development and improvement of various TEM, STEM and AEM techniques for yielding information on the structure and chemistry of catalysts on the nanometer scale. Here we review some quantitative approaches to catalyst characterization that have resulted from new developments in instrumentation.HREM has been used to examine structural features of catalysts often by employing profile imaging techniques to study atomic details on the surface. Digital recording techniques employing slow-scan CCD cameras have facilitated the use of low-dose imaging in zeolite structure analysis and electron crystallography. Fig. la shows a low-dose image from SSZ-33 zeolite revealing the presence of a stacking fault.


2019 ◽  
Author(s):  
Julio Ignacio Urzúa ◽  
Sandra Campana ◽  
Massimo Lazzari ◽  
Mercedes Torneiro

Tetraphenylmethane has emerged as a recurrent building block for advanced porous materials such as COFs, PAFs and hypercrosslinked polymers. Guided by a similar design principle, we have previously synthesized shape-persistent dendrimers with tetraphenylmethane nodes and ethynylene linkers. Here we report the generality of our approach by describing new dendritic architectures built from tetraphenylmethane. First, we prepared expanded dendrimers where the tetrahedral units are bonded through larger rigid rod spacers. Among the different synthetic strategies tested, the convergent route, with alternating steps of Pd-catalyzed Sonogashira coupling and alkyne activation by removal of TMS masking groups, efficiently afforded the first- and second-generation dendrimers. A second type of compounds having a linear diyne at the core is also described. The dendrimers of generations 1-2 were also synthesized by a convergent approach, with the diyne being assembled in the last step of the synthesis by a Glaser oxidative homocoupling of the corresponding dendrons bearing a terminal alkyne at the focal point. A third-generation dendrimer was also successfully prepared by a double-phase strategy.<br>


2008 ◽  
Vol 2 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Jung Sub Lee ◽  
Seong-Jang Kim ◽  
Kuen Tak Suh ◽  
In-Ju Kim ◽  
Yong-Ki Kim

1984 ◽  
Vol 1 (2) ◽  
pp. 21-23 ◽  
Author(s):  
David A. Gansner ◽  
Owen W. Herrick

Abstract People who have to make decisions about cost-effective management for gypsy moth need help in predicting and evaluating its effects. Field plot data collected during recent outbreaks in Pennsylvania are being used to develop guides for predicting forest stand losses to the pest Presented here are some of the more useful products of that effort to date. Easy-to-measure data for forest characteristics such as species composition and crown condition can be collected and applied in models that estimate potential stand and tree mortality and changes in timber value. North. J. Appl. For. 2:21-23, June 1984.


Author(s):  
Na Zhang ◽  
Jinqian Deng ◽  
Fayyaz Ahmad ◽  
Muhammad Umar Draz

Green development is an important way to meet the challenges of ecological and environmental protection and economic growth, as well as an inevitable choice to realize China’s sustainable development in the new era. The Chinese economic system is such that local government competition has become a key factor affecting regional green development under the current leadership. Based on the inter-provincial panel data of 30 provinces in mainland China from 1997 to 2017, this paper uses the total-factor non-radial directional distance function and slack-based measure data envelopment analysis (SBM-DEA) to measure the green development efficiency of the provinces. Additionally, it also uses the Malmquist–Luenberger (ML) index to decompose green development efficiency and analyzes its internal driving factors. Finally, taking environmental regulation as a mediating variable, this paper empirically analyzes the influence mechanism of local government competition on green development efficiency from three perspectives including growth competition, fiscal competition and investment competition. The study found that: the green development efficiency of Chinese regions showed a downward trend, with significant regional differences; technological progress is the key factor to improve the efficiency of green development, and its role gradually decreases from eastern to western and central regions; pure technical efficiency has become a bottleneck restricting the improvement of green development efficiency, while scale efficiency shows significant regional differences; the growth competition, fiscal competition and investment competition of local government all have a significant inhibitory effect on the efficiency of green development. This paper puts forward policy suggestions supporting enterprise technology research and development, optimizing energy conservation and emission reduction as well as improving the local government performance evaluation system for green development.


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