selective heating
31Solar hot water — is water heated by the use of solar energy. Solar heating systems are generally composed of solar thermal collectors, a fluid system to move the heat from the collector to its point of usage. The system may use electricity for pumping the fluid,… …
32Solar energy — is the light and radiant heat from the Sun that powers Earth s climate and weather and sustains life. Since ancient times it has been harnessed for human use through a range of technologies. Solar radiation along with secondary solar resources… …
33Interstellar medium — Interstellar redirects here. For other uses, see Interstellar (disambiguation). The distribution of ionized hydrogen (known by astronomers as H II from old spectroscopic terminology) in the parts of the Galactic interstellar medium visible… …
34Thermochromism — is the ability of substance to change color due to a change in temperature. A mood ring is an excellent example of this, but it has many other uses. Thermochromism is one of several types of chromism.The two basic approaches are based on liquid… …
35food preservation — Any method by which food is protected against spoilage by oxidation, bacteria, molds, and microorganisms. Traditional methods include dehydration, smoking, salting, controlled fermentation (including pickling), and candying; certain spices have… …
36environmental works — ▪ civil engineering Introduction infrastructure that provides cities and towns with water supply, waste disposal, and pollution control services. They include extensive networks of reservoirs, pipelines, treatment systems, pumping stations …
37metamorphic rock — Any of a class of rocks that result from the alteration of preexisting rocks in response to changing geological conditions, including variations in temperature, pressure, and mechanical stress. The preexisting rocks may be igneous, sedimentary,… …
38Soldering — For the song, see Soldering (song). For the product, see Solder. Desoldering a contact from a wire. Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal (solder) into the joint, the… …
39Brazing — This article is about the metal joining process. For the cooking technique, see braising. Brazing practice Brazing is a metal joining process whereby a filler metal is heated above and distributed between two or more close fitting parts by… …
40Chlorpromazine — Systematic (IUPAC) name …
