On a Subposet of the Tamari Lattice

We explore some of the properties of a subposet of the Tamari lattice introduced by Pallo, which we call the comb poset. We show that three binary functions that are not well-behaved in the Tamari lattice are remarkably well-behaved within an interval of the comb poset: rotation distance, meets and joins, and the common parse words function for a pair of trees. We relate this poset to a partial order on the symmetric group studied by Edelman.Comment: 21 page

Gold in the past, today and future

This paper deals with gold, which is described as a chemical element. Special attention is paid to its physical-chemical properties and, furthermore, where or in what form it can be found in nature. We discuss the role it has played through history and we inform how gold has been developed to the level it has reached today's value. Still more, when gold is broken into nanoparticles, this form could be highly useful for a wide range of processes, including general nanotechnology, electronics manufacturing and the synthesizing of different functional materials. It is important that we know that gold is also used in industry in many engineering applications (contacts in micro-electronics) and medicine (dental alloys, implants)

Zlato u prošlosti, sadašnjosti i budućnosti

This paper deals with gold, which is described as a chemical element. Special attention is paid to its physical-chemical properties and, furthermore, where or in what form it can be found in nature. We discuss the role it has played through history and we inform how gold has been developed to the level it has reached today’s value. Still more, when gold is broken into nanoparticles, this form could be highly useful for a wide range of processes, including general nanotechnology, electronics manufacturing and the synthesizing of different functional materials. It is important that we know that gold is also used in industry in many engineering applications (contacts in micro-electronics) and medicine (dental alloys, implants).Ovaj članak govori o zlatu kao kemijskom elementu. Posebna pažnja posvećena je njegovim fizikalno-kemijskim svojstvima i gdje i u kojem obliku se može pronaći u prirodi. Razmatra se uloga koju je zlato odigralo u povijesti i donosi se informacije o tome kako je doseglo razinu vrijednosti koju ima danas. Zlato razlomljeno na nanočestice upotrebljivo je u širem spektru procesuiranja, uključujući opću nanotehnologiju, elektroničku prizvodnju i spajanju materijala raznih funkcionalnosti. Važno je znati da se zlato koristi i u industriji, mnogim inženjerskim procesima (kontakti u mikro-elektronici) i medicini (dentalne slitine, implatanti)

Microgravity Combustion Diagnostics Workshop

Through the Microgravity Science and Applications Division (MSAD) of the Office of Space Science and Applications (OSSA) at NASA Headquarters, a program entitled, Advanced Technology Development (ATD) was promulgated with the objective of providing advanced technologies that will enable the development of future microgravity science and applications experimental flight hardware. Among the ATD projects one, Microgravity Combustion Diagnostics (MCD), has the objective of developing advanced diagnostic techniques and technologies to provide nonperturbing measurements of combustion characteristics and parameters that will enhance the scientific integrity and quality of microgravity combustion experiments. As part of the approach to this project, a workshop was held on July 28 and 29, 1987, at the NASA Lewis Research Center. A small group of laser combustion diagnosticians met with a group of microgravity combustion experimenters to discuss the science requirements, the state-of-the-art of laser diagnostic technology, and plan the direction for near-, intermediate-, and long-term programs. This publication describes the proceedings of that workshop

Liquid metal/ceramic interfaces in dental practice and jewellery manufacturing

Metal-ceramic fusing has been the essential step in obtaining materials that benefit from both ceramic and metal constituents. i e where the combined properties of metal and ceramic layers are desirable When considering fusing methods. soldering and active metal brazing are the most effective These processes involve braze melting and flowing between the two pieces of material In the first part the phenomena occurring on the boundary between the ceramics and the active filler metal during the metal-ceramics joining are discussed Three interconnected sub-processes are considered (1) wetting of the ceramic surface. (2) chemical reactions at the Interlace and (3) diffusion with a moving interface Then, the appearances at the grain boundary grooves of the ceramic surface are presented as phenomena on the catalytic surface In the second pan, examples from dental practice and jewellery manufacturing are used for comparative analysis Finally we discuss the composition and properties of the soldering and brazing alloys used for dental practice and jewellery manufacturin

Deutes, torts i injúries d'una comtessa de Pallars. Reflexions sobre la mentalitat feudal

L'any 1350, el papa Climent VI va proclamar el jubileu per tota la cristiandat. Era el segon jubileu general que proclamava l'Església. El primer havia estat cinquanta anys abans, en temps del papa Bonifaci VIII, el qual va concedir just al començar el segle XIX 'El Gran Perdó Jubilar'. Aquest fet s'emmarcava en el context de la voluntat per part del papat de reafirmar la funció carismàtica de l'Església, i a la vegada recollia l'anhel de la salvació col.lectiva que havia inspirar tota l'experiència escatològica dels segles anteriors

Microwave sintering of BaTiO₃ ceramics

Barium titanate and BaTiO₃-based multilayer capacitors were sintered in a commercial microwave oven. The oven was equipped with a 2.45 GHz continuous-wave magnetron with a maximum power output of 650 watts. Microwave-absorbing setters made of SiC were used to offset thermal losses from the samples and allow sintering temperatures (\u3e1325°C) to be achieved. Pure samples were pressed from commercial BaTiO₃ powder and microwave sintered to about 90% of theoretical density. Multilayer capacitors were obtained from commercial manufacturers and used in all sintering experiments. A comparison between microwave sintered material and identical samples sintered in a conventional electric furnace revealed no difference in measured dielectric properties. The temperature uniformity within the microwave oven and the relative energy efficiency of the sintering process were also examined. An experimental design using a single-mode resonant cavity for heating was proposed --Abstract, page ii