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Teclu Burner
The Teclu burner is an ambient air laboratory gas burner, that was created by Romanian chemist Nicolae Teclu in 1882. The burner is most commonly used to heat substances in a laboratory, can be used for sterilisation and sometimes it is used for soldering or glasswork. It is commonly made from brass or iron.The burner physically consists of a round base, a tube connected to it providing the gas to the flame and a vertical metal tube that directs the flame upwards. The tube has a conical shape closer to the base. The burner was created on the basis of Nicolae Teclu's previous studies on flame spectroscopy and specifically, his experiments including flames positioned at different levels in a tube. Teclu was able to conclude that changing the position of the flame in a vertical tube can effect the splitting of the flame and optimize the heat produced by the flame. As a result of this alteration, this burner compared with the Bunsen burner is able to produce higher flame temperature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicolae Teclu
Nicolae Teclu (); (11 October 1839, Kronstadt, Austrian Empire (today Brașov, Romania) – 13 July 1916, Vienna, Austria-Hungary) was a Romanian chemist, who gave his name to the worldwide-used "Teclu burner". He studied engineering and architecture, and then chemistry, continuing his career by becoming professor for general and analytical chemistry in Vienna. He also contributed substantially to the worldwide development of chemistry. Biography He studied chemistry at the Vienna Polytechnic Institute and later changed to architecture at the Academy of Fine Arts in Munich. After a short time in Romania he went back to Vienna becoming a professor for general and analytical chemistry in Vienna. In 1892 he published his invention of the gas burner with a mechanism to control the respective amounts of methane gas and air. His burner produces a hotter flame than the Bunsen Burner, thus making it superior. The usage of Teclu burners is very common not only in Romania, but also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burners
Burning Man is an event focused on community, art, self-expression, and self-reliance held annually in the western United States. The name of the event comes from its culminating ceremony: the symbolic burning of a large wooden effigy, referred to as the Man, that occurs on the penultimate night of Burning Man, which is the Saturday evening before Labor Day. The event has been located since 1991 at Black Rock City in northwestern Nevada, a temporary city erected in the Black Rock Desert about north-northeast of Reno. As outlined by Burning Man co-founder Larry Harvey in 2004, the event is guided by ten principles: radical inclusion, gifting, decommodification, radical self-reliance, radical self-expression, communal effort, civic responsibility, leaving no trace, participation, and immediacy. The event originated on June 22, 1986, on Baker Beach in San Francisco as a small function organized by Larry Harvey and Jerry James, the builders of the first Man. It has since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Needle Valve
A needle valve is a type of valve with a small port and a threaded, needle-shaped plunger. It allows precise regulation of flow, although it is generally only capable of relatively low flow rates. Construction and operation An instrument needle valve uses a tapered pin to gradually open a space for fine control of flow. The flow can be controlled and regulated with the use of a spindle. A needle valve has a relatively small orifice with a long, tapered seat, and a needle-shaped plunger on the end of a screw, which exactly fits the seat. As the screw is turned and the plunger retracted, flow between the seat and the plunger is possible; however, until the plunger is completely retracted, the fluid flow is significantly impeded. Since it takes many turns of the fine-threaded screw to retract the plunger, precise regulation of the flow rate is easily possible. The virtue of the needle valve is from the vernier effect of the ratio between the needle's length and its diameter, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meker–Fisher Burner
A Meker–Fisher burner, or Meker burner, is an ambient air laboratory burner that produces multiple open gas flames, used for heating, sterilization, and combustion. It is used when laboratory work requires a hotter flame than attainable using a Bunsen burner, or used when a larger-diameter flame is desired, such as with an inoculation loop or in some glassblowing operations. The burner was introduced by French chemist Georges Méker in an article published in 1905.G. Meker. Nouveaux bruleurs de laboratoire et leur application au chauffage a temperature elevee. ''J. Phys. Theor. Appl.'', 1905, 4 (1), pp. 348–35Deposited copy at l'archive ouverte HAL/ref> The Meker–Fisher burner heat output can be in excess of per hour (about 3.5 k W) using LP gas. Flame temperatures of up to are achievable. Compared with a Bunsen burner, the lower part of its tube has more openings with larger total cross-section, admitting more air and facilitating better mixing of air and gas. The tube i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemist
A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms. Chemists carefully measure substance proportions, chemical reaction rates, and other chemical properties. In Commonwealth English, pharmacists are often called chemists. Chemists use their knowledge to learn the composition and properties of unfamiliar substances, as well as to reproduce and synthesize large quantities of useful naturally occurring substances and create new artificial substances and useful processes. Chemists may specialize in any number of subdisciplines of chemistry. Materials scientists and metallurgists share much of the same education and skills with chemists. The work of chemists is often related to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Spectroscopy
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functional groups in solid, liquid, or gaseous forms. It can be used to characterize new materials or identify and verify known and unknown samples. The method or technique of infrared spectroscopy is conducted with an instrument called an infrared spectrometer (or spectrophotometer) which produces an infrared spectrum. An IR spectrum can be visualized in a graph of infrared light absorbance (or transmittance) on the vertical axis vs. frequency, wavenumber or wavelength on the horizontal axis. Typical units of wavenumber used in IR spectra are reciprocal centimeters, with the symbol cm−1. Units of IR wavelength are commonly given in micrometers (formerly called "microns"), symbol μm, which are related to the wavenumber in a reciprocal way. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near-infrared Spectroscopy
Near-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum (from 780 nm to 2500 nm). Typical applications include medical and physiological diagnostics and research including blood sugar, pulse oximetry, functional neuroimaging, sports medicine, elite sports training, ergonomics, rehabilitation, neonatal research, brain computer interface, urology (bladder contraction), and neurology (neurovascular coupling). There are also applications in other areas as well such as pharmaceutical, food and agrochemical quality control, atmospheric chemistry, combustion research and astronomy. Theory Near-infrared spectroscopy is based on molecular overtone and combination vibrations. Such transitions are forbidden by the selection rules of quantum mechanics. As a result, the molar absorptivity in the near-IR region is typically quite small. (NIR absorption bands are typically 10–100 times weaker than the corre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crucible Swelling Number
A crucible is a ceramic or metal container in which metals or other substances may be melted or subjected to very high temperatures. While crucibles were historically usually made from clay, they can be made from any material that withstands temperatures high enough to melt or otherwise alter its contents. History Typology and chronology The form of the crucible has varied through time, with designs reflecting the process for which they are used, as well as regional variation. The earliest crucible forms derive from the sixth/fifth millennium B.C. in Eastern Europe and Iran. Chalcolithic Crucibles used for copper smelting were generally wide shallow vessels made from clay that lacks refractory properties which is similar to the types of clay used in other ceramics of the time. During the Chalcolithic period, crucibles were heated from the top by using blowpipes.Hauptmann A., 2003, ''Developments in copper Metallurgy During the Fourth and Third Millennia B.C. at Feinan'', Jorda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schlenk Line
The Schlenk line (also vacuum gas manifold) is a commonly used chemistry apparatus developed by Wilhelm Schlenk. It consists of a dual manifold with several ports. One manifold is connected to a source of purified inert gas, while the other is connected to a vacuum pump. The inert-gas line is vented through an oil bubbler, while solvent vapors and gaseous reaction products are prevented from contaminating the vacuum pump by a liquid-nitrogen or dry-ice/acetone cold trap. Special stopcocks or Teflon taps allow vacuum or inert gas to be selected without the need for placing the sample on a separate line. Schlenk lines are useful for safely and successfully manipulating moisture- and air-sensitive compounds. The vacuum is also often used to remove the last traces of solvent from a sample. Vacuum and gas manifolds often have many ports and lines, and with care, it is possible for several reactions or operations to be run simultaneously. When the reagents are highly susceptible t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beryllium
Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with other elements to form minerals. Notable gemstones high in beryllium include beryl ( aquamarine, emerald) and chrysoberyl. It is a relatively rare element in the universe, usually occurring as a product of the spallation of larger atomic nuclei that have collided with cosmic rays. Within the cores of stars, beryllium is depleted as it is fused into heavier elements. Beryllium constitutes about 0.0004 percent by mass of Earth's crust. The world's annual beryllium production of 220 tons is usually manufactured by extraction from the mineral beryl, a difficult process because beryllium bonds strongly to oxygen. In structural applications, the combination of high flexural rigidity, thermal stability, thermal conductivity and low density (1.85 times that of water) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
