Philosophical Foundations of Physics by Rudolf Carnap Rudolph Carnap (1966) Philosophical Foundations of Physics Source: Philosophical Foundations of Physics (1966) publ. Basic Books Inc. ONE OF THE most important distinctions between two types of laws in science is the distinction between what may be called (there is no generally accepted terminology for them) empirical laws and theoretical laws. Here, a warning must be issued. A philosopher might object that the intensity of an electric current is not really observed. The physicist would reply that this was true enough, but the inference was not very complicated. There is no question here of who is using the term “observable” in a right or proper way. Empirical laws, in my terminology, are laws containing terms either directly observable by the senses or measurable by relatively simple techniques. There is no commonly accepted term for the second kind of laws, which I call theoretical laws. Theoretical laws are, of course, more general than empirical laws. Chapter 24Correspondence Rules
Oxygen (O) and water Oxygen is the most abundant element on earth. Oxygen exists as O2 and O3 (ozone), and is present in a number of compounds including water molecules. It can be found dissolved in water as O2 molecules. Consequently, the oxygen content of seawater is 85.7%. In what way and in what form does oxygen react with water? Gaseous oxygen does not react with water. O2 + 2 H2O + 4 e- -> 4 OH- Oxygen may oxidize organic matter. Fe2+ + 0,25 O2 -> Fe(OH)3 + 2,5 H+ Mn2+ + O2 -> MnO2 + 2 H+ NH4+ + 2 O2 -> NO3- + 6 H+ CH4 + 2 O2 -> CO2 + 4 H+ These mechanisms show that ammonium and methane apply large amounts of oxygen, and the resulting oxidation reactions form higher or lower amounts of acid. Solubility of oxygen and oxygen compounds Water solubility of oxygen at 25oC and pressure = 1 bar is at 40 mg/L water. Why is oxygen present in water? As was described earlier, oxygen dissolves naturally when water comes in contact with air. What are the environmental effects of oxygen in water?
Sagittarius Constellation: Facts, Mythology, Stars, Location, Star Map | Constellation Guide Sagittarius constellation lies in the southern sky. It is one of the constellations of the zodiac. The constellation represents the archer in Greek mythology and is usually depicted as a centaur holding a bow and arrow. Sagittarius’ location is easy to find because the constellation lies on the Milky Way. Its symbol is ♐. Like other zodiac constellations, Sagittarius was originally catalogued by the Greek astronomer Ptolemy in the 2nd century. The constellation contains the luminous Pistol Star, the galactic centre, the radio source Sagittarius A, and a number of very famous deep sky objects, including the Sagittarius Dwarf Elliptical Galaxy, the Sagittarius Dwarf Irregular Galaxy, Barnard’s Galaxy, the Bubble Nebula, and as many as 15 Messier objects, among them the Omega Nebula, the Lagoon Nebula, and the Trifid Nebula. Sagittarius Constellation Map, by IAU and Sky&Telescope magazine Sagittarius is the 15th largest constellation in the sky. Nunki – σ Sagittarii (Sigma Sagittarii)
This stunning animal looks like a glitch in reality's programming Isn't there a butterfly with similar properties? SExpand Morpho butterfly? There was a clothing company called Biomimetic Design that claimed to have been able to duplicate the effect, but I think they're defunct or something now. Photon Nomenclature[edit] In 1900, Max Planck was working on black-body radiation and suggested that the energy in electromagnetic waves could only be released in "packets" of energy. In his 1901 article [4] in Annalen der Physik he called these packets "energy elements". The word quanta (singular quantum) was used even before 1900 to mean particles or amounts of different quantities, including electricity. Physical properties[edit] The cone shows possible values of wave 4-vector of a photon. A photon is massless,[Note 2] has no electric charge,[13] and is stable. Photons are emitted in many natural processes. The energy and momentum of a photon depend only on its frequency (ν) or inversely, its wavelength (λ): where k is the wave vector (where the wave number k = |k| = 2π/λ), ω = 2πν is the angular frequency, and ħ = h/2π is the reduced Planck constant.[17] Since p points in the direction of the photon's propagation, the magnitude of the momentum is Experimental checks on photon mass[edit]
Hierochloe odorata Characteristics[edit] Hierochloe odorata is a very hardy perennial. Its leaves do not have rigid stems, so only grow to about 20 cm (7.9 in) in height, and then the leaves grow outward horizontally to 100 cm (39 in) long or more, by late summer. The bases of the leaves, just below the soil surface are broad and white, without hairs; the underside of the leaves are shiny, without hairs. In the wild, the bases of the leaves are frequently purple-red colored, this indicates a phosphorus-deficient soil. There are several strains of sweetgrass—a regular strain that can be harvested once or twice a year, and a naturally occurring polyploid strain, which is much faster growing and can be harvested three to five times a year. [3] Taxonomy[edit] The name Hierochloe odorata is from the Greek, literally "holy fragrant grass". Propagation[edit] Easiest by cutting out plugs from established plants. Distribution[edit] Uses[edit] European traditions[edit] Native American traditions[edit] References[edit]
Chinese Beautyberry - Wikipedia In den Blattachseln der gegenständigen Laubblätter die Blütenstände von Callicarpa giraldii var. giraldii 'Profusion'. Die Chinesische Schönfrucht (Callicarpa giraldii), auch einfach Schönfrucht, Purpur-Schönfrucht oder Liebesperlenstrauch genannt, ist eine Pflanzenart, die zur Familie der Lippenblütler (Lamiaceae) gehört. Sie wird in Parks und Gärten der Gemäßigten Klimazonen als Zierpflanze verwendet. Hauptsächlich wird die Sorte 'Profusion' der Varietät Callicarpa giraldii var. giraldii angepflanzt. Beheimatet ist diese Pflanzenart in Mittel- bis Westchina, in Höhenlagen von 200 bis 3400 Meter. Beschreibung[Bearbeiten] Sehr zierend sind die sich sehr zahlreich am zweijährigen Holz bildenden, beerenartigen Steinfrüchte. Systematik[Bearbeiten] Es werden drei Varietäten unterschieden: Von manchen Autoren wird die Gattung Callicarpa in die Familie der Eisenkrautgewächse (Verbenaceae) gestellt. Bilder[Bearbeiten] Quellen[Bearbeiten] Shou-liang Chen und Michael G. Weblinks[Bearbeiten]