ball lightning is an unexplained and potentially dangerous atmospheric electrical phenomenon. the term refers to reports of luminescent, spherical objects that vary from pea-sized to several meters in diameter.though usually associated with thunderstorms, the phenomenon lasts considerably longer than the split-second flash of a lightning bolt. two reports from the nineteenth century claim that .
in 1984, artichoke fields were reported to have been infected with powdery mildew for the first time. in the ensuing years the disease continued to reappear with each year the disease becoming more widespread than in the past. the fungus colonizes the underside of leaves and the wind carries spores between fields.
a cactus plural: cacti, cactuses, or less commonly, cactus is a member of the plant family cactaceae, a family comprising about 127 genera with some 1750 known species of the order caryophyllales. the word 'cactus' derives, through latin, from the ancient greek κάκτος, kaktos, a name originally used by theophrastus for a spiny plant whose identity is not certain.
gauge symmetry was generalized mathematically in 1954 by chen ning yang and robert mills in an attempt to describe the strong nuclear forces. this idea, dubbed yang–mills theory, later found application in the quantum field theory of the weak force, and its unification with electromagnetism in the electroweak theory.
over 7,500 cultivars of the culinary or eating apple malus pumila are known. some are extremely important economically as commercial products, though the vast majority are not suitable for mass production. in the following list, use for 'eating' means that the fruit is consumed , rather than cooked.
millipedes are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class diplopoda, the name being derived from this feature. each double-legged segment is a result of two single segments fused together. most millipedes have very elongated cylindrical or flattened bodies with more than 20 segments, while pill millipedes are shorter and can roll into a ball. although the name 'millipede' derives from the lati
the car would be rolled up two checkered ramps, to a raised platform a few feet above the ground. in 1986, a new victory lane was constructed, which was a hydraulic lift in the pit lane. in 1994, after the pit lane was reconstructed, victory lane was moved back to the horseshoe area, this time on a large cylindrical platform.
iso 4371:1984 measurement of liquid flow in open channels by weirs and flumes – end depth method for estimation of flow in non-rectangular channels with a free overfall approximate method iso 4373:2008 hydrometry – water level measuring devices
research in lithium-ion batteries has produced many proposed refinements of lithium-ion batteries. . in 1984, researchers at bell . anode with an energy density above 1,100 mah/g and a durability of 600 cycles that used porous silicon particles using ball-milling and stain-etching. .
the sydney observatory is a heritage-listed meteorological station, astronomical observatory, function venue, science museum, and education facility located on observatory hill at upper fort street, in the inner city sydney suburb of millers point in the city of sydney local government area of new south wales, australia.it was designed by william weaver plans and alexander dawson .
in attrition, macro- or micro-scale particles are ground in a ball mill, a planetary ball mill, or other size-reducing mechanism. the resulting particles are air classified to recover nanoparticles. in pyrolysis, a vaporous precursor liquid or gas is forced through an orifice at high pressure and burned. the resulting solid a version of soot .
this is a list of issue covers of tv guide magazine from the decade of the 1980s, from january 1980 to december 1989. the entries on this table include each cover's subjects and their artists photographer or illustrator . this list is for the regular weekly issues of tv guide; any one-time-only special issues are not included.