Haber and Bosch


Cyclone Problems. Problems may be encountered in cyclone appHcation because of fouling and caking, or from erosion, or when using multiple cyclones. Multiple cyclones are designed so that each cyclone handles a prorated share of gas and dust and the overall efficiency of the system is the same as that calculated for an individual unit. This is the case, however, only when each cyclone receives identical dust fractions (size and loading) and gas flow. Since cyclone efficiency increases with flow and dust loading and is affected by particle-size distribution, the design of the inlet gas distribution system must accomplish the proper distribution. Otherwise, those cyclones with lower gas flow and dust concentration (and perhaps finer dust) will have much poorer efficiency. When multiple cyclones share a common dust hopper, it is important that all cyclones have essentially uniform pressures at the cone apex. Wall caking, unequal gas flow or dust distribution resulting from pressure drop decreases that occur with increases in dust loading, or partial plugging of cone or cyclone inlets can all cause unequal apex pressures. Unequal pressures will cause gas from higher pressure cyclones to flow into the dust hopper and back into the cyclones having lower apex pressure. This short-circuiting can result in heavy dust reentrainment and decreased efficiency.  [c.397]

In 1838, Frederic Kuhlmann discovered die formation of nitrogen oxide (NO) during die catalytic oxidation of ammonia. Wilhelm Ostwald developed die production mediods in 1902 and established die base for today s major commercial processes. However, industrial production began only after Haber and Bosch developed the synthesis of ammonia around 1916.  [c.86]

J. Bagg, M. B. Abramson, M. Fishman, M. D. Haber, and H. P Gregor, J. Am. Chem. Soc., 86, 2759 (1964).  [c.167]

Doses range from 6 to 33 ppm ia the diet, but very htde if any ionophore can be measured ia the circulation after feeding. Monensia is absorbed from the gut, metabolized by the Hver, and excreted iato the bile and back iato the gut. Thus tissue and blood concentrations are very low. Over 20 metabohtes of monensia, which have Htde or ao biological activity, have beea ideatified (47,55).  [c.410]

Fig. 1-1. Lead smelting furnace. Source G. Agricola, "De Re Metallica," Book X, p. 481, Basel, Switzerland, 1556. Translated by H. C. Hoover and L. H. Hoover, Mining Magazine, London, 1912. Reprinted by Dover Publications, New York, 1950. Fig. 1-1. Lead smelting furnace. Source G. Agricola, "De Re Metallica," Book X, p. 481, Basel, Switzerland, 1556. Translated by H. C. Hoover and L. H. Hoover, Mining Magazine, London, 1912. Reprinted by Dover Publications, New York, 1950.
By contrast with the elusive though isolable HOF, the history of HOCl goes back over two centuries to the earliest experiments of C. W. Scheele with CI2 in 1774 (p. 792), and the bleaching and sterilizing action of hypochlorites have long been used both industrially and domestically. HOCl, HOBr and HOI are all highly reactive, relatively unstable compounds that are known primarily in aqueous solutions. The most convenient preparation of such solutions is by perturbing the hydrolytic disproportionation equilibrium (p. 856)  [c.857]

RC0)3N (tertiary). The amides are crystalline solids soluble in alcohol and ether some are also soluble in water. Primary amides are prepared by the action of ammonia or amines on acid chlorides, anhydrides, or esters. Some amides are prepared by distillation of the ammonium salt of the appropriate acid. Secondary and tertiary amides are formed by treating nitriles or primary amides with organic acids or their anhydrides. Primary amides react with nitrous acid to give carboxylic acids in many cases, healing with mineral acids or alkalis has the same effect. Primary amides are weakly basic. Compounds are formed with metals such as sodium, potassium, and mercury. HCIO and HBrO react to give N-chlor- or bromamides these give amines when treated with alkali. Alkylated amides, particularly dimethylacetamide and dimethylformamide are good solvents for conducting replacement reactions involving ionic reagents (e.g. replacement of a chlorine atom by fluorine using K.F).  [c.27]

This section provides an overview and review of quantum mechanics calculations. The information can help you use Hyper-Chem to solve practical problems. For quantitative details of quantum mechanics calculations and how HyperChem implements them, see the second part of this book. Theory and Methods.  [c.31]

The first basic approximation of quantum chemistry is the Born-Oppenheimer Approximation (also referred to as the clamped-nuclei approximation). The Born-Oppenheimer Approximation is used to define and calculate potential energy surfaces. It uses the heavier mass of nuclei compared with electrons to separate the  [c.161]

A mechanized, submerged-arc-welding system requites a power source, control system, and wine-feed provisions. Granulated flux is fed into the weld joint from a flux hopper, which travels ahead of the welding arc as part of the electrode carriage. Control of the welding torch along the seam of the base metal can be accompHshed by a motorized electrode carriage moving along a straight beam, or by a positioner capable of placing the welding torch at any position over a base metal that is itself continually changing position.  [c.343]

Flammability Acrolein is very flammable its flash point is <0° C, but a toxic vapor cloud will develop before a flammable one. The flammable limits in air are 2.8% and 31.0% lower and upper explosive limits, respectively by volume. Acrolein is only partly soluble in water and will cause a floating fire, so alcohol type foam should be used in firefighting. The vapors are heavier than air and can travel along the ground and flash back from an ignition source.  [c.128]

Reverse or backflow bag filters are rather similar in appearance to shaker filters except that the shaking mechanism is eliminated. The stockings are clamped to a tube sheet at the bottom and are closed at the upper end with a metal cap from which they are suspended. Dirty gas enters below the tube sheet and passes upward through the bag. When the bag cleaning cycle begins, the flow of dirty gas is shut off, and a fan forces cleaned gas backward through the bags. A series of rings, sewn into the bags at intervals, prevent the complete coUapse of the bag under the reverse-flow conditions. Dust dislodged by the backflow falls down through the bag to a dust hopper below the tube sheet. The quantity of back-flush gas is usually sufficient to produce a reverse-flow superficial velocity of 0.5—0.6 m /min through the bag. Woven fabrics are generally used for reverse-flow bag filters. The small reverse-flow pressures generally used would be insufficient to back-flush felt bags. The principal appHcation for reverse-flow cleaning is in bag-houses using fiberglass bags that handle gas at temperatures above 150°C such as boiler flue gas containing flyash. Bag coUapse and reinflation must be sufficiently gentle that excessive stress is not appHed to the fiberglass fabric.  [c.404]

Endless belt percolation extractors (Fig. 5) such as the uncompartmented de Smet belt extractor and the compartmented Lurgi frame belt extractor are similar in principle and closely resemble a belt filter, and are probably the simplest type of percolation extractor from a mechanical point of view. These are fitted with a slow-moving perforated belt. The belt is made from steel mesh cloths when the soHds are fine, or coarser screens when the soHds are larger, and is attached to chains which pass over sprockets at each end of the extractor. The soHd is fed from a hopper at one end of the extractor to the moving belt, and the bed height is controlled by an adjustable damper at the oudet of the feed hopper. The two side walls of the extractor provide support for the bed on the moving belt. Fresh solvent is fed by spraying it onto the bed close to the discharge end of the belt, but leaving sufficient distance for adequate drainage of the bed prior to discharge. MisceUa draining from the bed is collected in a pan below the belt and circulated back to be sprayed onto the bed at a point closer to the soHds-feed end of the belt this process is repeated to achieve extraction operating with a countercurrent flow. The top of the bed is scraped by a hinged rake which has two functions (/) it prevents a layer of fine soHds from accumulating at the top of the bed thereby reducing permeabihty, and (2) it form a soHds pile which helps to prevent intermingling of misceUa from different feed points at the surface of the bed. The belt is effectively washed twice once by fresh solvent just after the soHds discharge point, and then at the other end of the belt return by misceUa. The extraction time and percolation rate determine the belt speed and the amount of drainage area, and hence linear length of belt, requited. These parameters control the plant capacity as the bed height is fixed by the mechanical design of the extractor.  [c.92]

Automatic molding permits high speed mass production it is preferable to machining finished material. Automatic presses can be operated mechanically, pneumatically, or hydraulically. The mold is filled by means of a special metering system from a storage hopper containing a free-flowing resin. Loading buckets that shutde back and forth over the single-cavity mold are also used. Because automatic molding requires short cycles, the powder is usually compressed at high speed with a high preform pressure. Small articles such as rings, bushings, washers, gaskets, and baH-valve seats can be molded by this technique.  [c.353]

In the process, finely cmshed coal is gasified at atmospheric pressure in a fluidized state oxygen and steam are introduced at the base of the gasifier. The coal is fed by lockhoppers and a screw feeder into the bottom of the fuel bed. Sintered ash particles settle on a grate, where they are cooled by the incoming oxygen and steam a rotating, cooled rabble moves the ash toward a discharge port. The ash is then conveyed pneumatically to a disposal hopper.  [c.68]

Natural-gas components include water vapor, carbon dioxide (qv), sometimes hydrogen sulfide, heavier hydrocarbons (qv), methane, nitrogen, small amounts of argon, traces of neon and hydrogen, and helium. The production of pure helium from natural gas requires three basic processing steps (73).  [c.10]

Density is a particularly important characteristic of alloys used in rotating machinery, because centrifugal stresses increase with density. Densities of the various metals in Table 1 range from 6.1 to 19.3 g/cm. Those of iron, nickel, and cobalt-base superaHoys fall in the range 7-8.5 g/cm. Those alloys which contain the heavier elements, ie, molybdenum, tantalum, or tungsten, have correspondingly high densities.  [c.109]

With this type of burner, a wide variety of raw materials, ranging from propane to naphtha, and heavier hydrocarbons containing 10—15 carbon atoms, can be used. In addition, the pecuhar characteristics of the different raw materials that can be used enable the simultaneous production of acetylene and ethylene (and heavier olefins) ia proportioas which can be varied within wide limits without requiring basic modifications of the burner.  [c.388]

Only a small (ca 3%) fraction of ingested or inhaled manganese is absorbed, which occurs primarily by the intestines (209). Once absorbed, manganese is regulated by the Hver, where it is excreted into the bile and passes back into the intestine, where some reabsorption may occur (210). Manganese is elirninated almost exclusively (>95%) by the bile in the gastrointestinal tract.  [c.526]

Water. The dehydration of natural gas and air was the first of the gas-purification appHcations of molecular sieves. Because of their high adsorptive selectivity for water and high capacity at low water partial pressures, molecular sieves were an obvious choice for water removal from natural gas and air before cryogenic extraction of helium and cryogenic separation of oxygen, nitrogen, and the rare gases, respectively. Molecular-sieve dehydration is used in the cryogenic production of Hquifted natural gas (LNG), for smaH-peak demand-type storage faciHties and giant base-load faciHties. In addition, molecular sieves have proved to be the most effective dehydration technique for the cryogenic recovery of ethane and heavier Hquids from natural gas.  [c.456]

The value of nitrogen compounds as an ingredient of mineral fertilizers was recognized ia 1840. Nitrogen is an essential element to plant growth and ammonia is the primary nitrogen source used ia fertilizers (qv). Until the early 1900s, the nitrogen source ia farm soils was entirely derived from natural sources from mineral resources such as CtuleaQ nitrates, from manure and the putrefaction of vegetable wastes and from ammonium sulfate from coal coking, seed meals, sewage sludges, and food processiag by-products. The synthesis of ammonia directiy from hydrogen [1333-74-0] (qv) and nitrogen [7727-37-9] (qv) on a commercial scale was pioneered by Haber and Bosch ia 1913, for which they were awarded Nobel prizes. Further developments ia economical, large scale ammonia production for fertilizers have made a significant impact on iacreases ia the world s food supply.  [c.335]

For example, if the user requests a molecular dynamics calculation using the AMBER force field, HyperChem starts a copy of Hyper-Newton running and sends it a copy of the chosen AMBERparam-eter set. It then sends it a copy of the current molecular system in the work space and the appropriate parameters for the molecular dynamics run. The back end runs the dynamics trajectory periodically sending back results to the front end to update the display of the molecule, plot structural or energetic values, etc. The front end and back end communicate via messages that are as appropriate to a distributed computing environment as they are to the single machine configuration.  [c.157]

Effects of repeated ethylene glycol peroral overexposure in treated rats and mice can result in kidney, Hver, and nervous system damage. The most sensitive indicators of ethylene glycol toxicity are disturbances in acid—base balance and nephrotoxic (kidney) effects. Effects of repeated chronic peroral overexposure of diethylene glycol in treated rats result in kidney and Hver damage (48).  [c.361]

Future space missions of long duration and long distance, eg, flights to Mars and back, would need a soHd-core nuclear rocket. The key measure of effectiveness of a rocket for propulsion is the specific impulse, defined as the ratio of thmst to mass flow rate of propeUant. Whereas a nuclear reactor cannot produce a gas temperature as high as a chemical fuel can, the former can use the light element hydrogen as coolant—propeUant, iastead of the heavier products of combustion.  [c.223]

Leather Dyes. The main classes of dyes employed ia the coloring of leather are the acid, acid/direct, direct, and basic types. On chrome leather, the direct dyes usually have greater affinity and produce fuller or heavier shades than do acid or chrome dyes. Acid/direct dyes as well as the meta11i2ed-type dyestuffs may be classified for the purpose of leather dyeiag as the maia types ia use. Basic dyes color chrome leather weakly and unevenly, unless the leather is first mordanted or retanned with suitable materials, such as vegetable tannin, syntans, or previously appHed acid and/or direct dyes. They may be used alone on vegetable-tanned leather to produce full shades or, as is done more frequendy, foUowiag a preliminary coloring with acid or acid/direct dyes. In the latter case, basic dyes are used to impart fullness of shade with minimum coloring matter and cost.  [c.375]

Another popular approach to the isothennal (canonical) MD method was shown by Nose [25]. This method for treating the dynamics of a system in contact with a thennal reservoir is to include a degree of freedom that represents that reservoir, so that one can perform deterministic MD at constant temperature by refonnulating the Lagrangian equations of motion for this extended system. We can describe the Nose approach as an illustration of an extended Lagrangian method. Energy is allowed to flow dynamically from the reservoir to the system and back the reservoir has a certain thermal inertia associated with it. However, it is now more common to use the Nose scheme in the implementation of Hoover [26].  [c.59]

The principal industries associated with the production of air pollution in the centuries preceding the Industrial Revolution were metallurgy, ceramics, and preservation of animal products. In the bronze and iron ages, villages were exposed to dust and fumes from many sources. Native copper and gold were forged, and clay was baked and glazed to form potterv and bricks before 4000 bc Iron was in common use and leather W as tanned before 1000 bc. Most of the methods of modern metallurgy were known before ad 1. They relied on charcoal rather than coal or coke. However, coal was mined and used for fuel before ad 1000, alfhough it was not made into coke until about 1600 and coke did not enter metallurgical practice significantly until about 1700. These industries and their effluents as they exisfed before 1556 are best described in the book "De Re Metallica" published in that year by Georg Bauer, known as Georgius Agricola (Fig. 1-1). This book was translated into English and published in 1912 by Herbert Clark Hoover and his wife (2).  [c.4]

Health Hazards Information - Recommended Personal Protective Equipment-. Chemical-type respirator rubber gloves chemical Goggles and face shield Symptoms Following Exposure-. May be absorbed through skin, lungs, or intestinal tract. Symptoms include salivation, leg and back muscle spasms, nausea, vomiting, hyper excitability, tremors, shivering, clonic convulsions, then titanic contraction of all skeletal muscles. Lethal doses cause respiratory failure. Respiration, affected as a result of the exertion from vomiting or convulsions, is first arrested because of titanic muscular contraction, then increased in both amplitude and rate as the muscles relax General Treatment for Exposure If symptoms of poisoning appear, promptly remove the unabsorbed pesticide from the stomach by inducing vomiting with warm salty or soapy water (if the patient is conscious) or from the skin with soap and water. Keep patient warm and quiet. Call a physician Toxicity by Inhalation (Threshold limit Value) Not pertinent Short-Term Exposure limits Not pertinent Toxicity by Ingestion Grade 4, LDjqbelow 50 mg/kg (dot) Late Toxicity Data not available Vapor (Gas) Irritant Characteristics The solid is non-volatile. For solutions, see meta-xylene Liquid or Solid Irritant Characteristics Minimum hazard. If spilled on clothing and allowed to remain, may cause smarting and reddening of the skin Odor Threshold Not pertinent.  [c.370]

Rabe and his collaborators have also effected the re-conversion of cinchonicine, quinicine and dihydroquinicine into cinchonine, quinine and dihydroquinine respectively, by treating them with sodium hypobromite, forming the 2i -bromo-derivative (VII) or the 8-bromo-derivative (Vila) as first employed by Kaufmann and Huber and produced by the action of bromine in hydrobromic acid. Either bromo-derivative is converted by alkali hydroxide into the corresponding quina-ketone (VIII), which is then reduced to the mixture of stereoisomerides of the dihydro-cinchona base (IX) by means of aluminium powder and sodium ethoxide solution. Later it was found that reduction can also be effected by catalytic hydrogenation with palladium in the case of the dihydro-bases, but when the latter process is applied to the vinyl-containing qu,ina-ketones the side-chain is reduced as well as the carbonyl group.  [c.460]

However, solubility, depending as it does on the rather small difference between solvation energy and lattice energy (both large quantities which themselves increase as cation size decreases) and on entropy effects, cannot be simply related to cation radius. No consistent trends are apparent in aqueous, or for that matter nonaqueous, solutions but an empirical distinction can often be made between the lighter cerium lanthanides and the heavier yttrium lanthanides. Thus oxalates, double sulfates and double nitrates of the former are rather less soluble and basic nitrates more soluble than those of the latter. The differences are by no means sharp, but classical separation procedures depended on them.  [c.1236]

These processes remained batch-type operations. As such they reached capacities in the range of 1,000—3,000 barrels per day (BPD). A truly novel approach to thermal cracking emerged from the facilities of the Universal Oil Products company in the late 1920s. To a greater extent than the other thermal cracking technologies, the so-called Dubbs Process approached continuous operations. Important elements of this technology were the continuous recycling of heavier byproducts back into the cracking section for further processing and the so-called bottom draw-off technique that continuously removed heavy liquid from the bottom portion of the soaking drum. This procedure reduced the rate of carbon buildup ill the system and so increased the time over which the still could operate before being shut down for cleaning.  [c.990]

The first industrial synthesis of NH3 from H2 and N2 started up in 1913 ( ) and was known as the Haber-Bosch process. Essentially the same catalyst is used today, with improvements. The catalyst is prepared by fusing Fe304 with a few percent of added K2O and AI2O3 and then heating in a N2-H2 mixture, whereby the iron oxide is reduced to mainly metallic iron. The AI2O3 acts as a structural promoter in ensuring that a high surface area, porous mass is obtained, with the iron present as small crystallites (the manner in which these crystallites form and sinter is important—note Ref. 254). The K2O acts as an electronic promoter, covering most of the internal surface [255] and changing its electronegativity. Poisons include CO2 (probably due to adsorption on the K2O), CO (probably due to adsorption on iron sites), and H2 and O2. Some useful general discussions are those by Ertl [256], Sinfelt [257], and Weinberg et al. [258]. Important older work is that of Emmett (see Ref. 259 and also Ref. 260). Boudart [261] gives a personalized discussion emphasizing Temkin s contributions.  [c.729]

Figure B3.4.5. Schematic plot of a two-dimensional potential surface for D + H2 restricted by an absorbing potential (shaded area). The absorbing potential i Vj (R, r) (shaded region) rises gently outward towards the edges of the grid. In practice, the grid needs to be extended only by =0.5-l A, or less for heavier mass systems. The absorbing potential imposes the correct boundary condition on the wavefiinction in the inner region. This basic paradigm of a small grid (denoted by dots), used in the strong-interaction region to describe the main part of the wavefiinction, applies in several different fomuilations time-independent arrangement-decouplmg scattering, where the time-mdependent wavefiinction r, ) is placed on this grid (supplemented by a fiinction describing the initial wavefiinction) time-dependent scattering (where it is used to describe the non-elastic part of the wavefiinction, and the elastic part is Figure B3.4.5. Schematic plot of a two-dimensional potential surface for D + H2 restricted by an absorbing potential (shaded area). The absorbing potential i Vj (R, r) (shaded region) rises gently outward towards the edges of the grid. In practice, the grid needs to be extended only by =0.5-l A, or less for heavier mass systems. The absorbing potential imposes the correct boundary condition on the wavefiinction in the inner region. This basic paradigm of a small grid (denoted by dots), used in the strong-interaction region to describe the main part of the wavefiinction, applies in several different fomuilations time-independent arrangement-decouplmg scattering, where the time-mdependent wavefiinction r, ) is placed on this grid (supplemented by a fiinction describing the initial wavefiinction) time-dependent scattering (where it is used to describe the non-elastic part of the wavefiinction, and the elastic part is
Bag filters may be woven or felted, an envelope ("pillow case") supported with an internal wire cage, or a long cylinder or stocking hung freely or containing an internal wire cage, and subject to either shaking or reverse flow for dust removal. Older filter installations employed woven cloth bags and the coUected dust was generally removed by shaking. Newer bag cleaning methods such as reverse flow utilize nonwoven felted bags. The avadabiHty of fibers is somewhat more limited with felts and one cannot choose a type of weave as with woven fabrics. Three main types of bag filters are illustrated in Figure 14. A fourth type uses backflow of gas, thus essentially providing back-flushing of the cloth. In most baghouse designs, there is some means of slowing the entering gas and deflecting it downward so that coarse dust particles drop out into the hopper. This may be as simple as routing the gas around an inlet baffle. In passing through the filter media, the majority of the dust coUects in a dust precoat built up on the bag surface and the cleaned air then flows to the gas oudet. Deposited dust is removed at intervals to prevent excessive pressure drop. In shaker-cleaning filters (envelope and stocking types), automatically controUed dampers shut off the air flow through the bag compartment when the bags are to be shaken. In filters designed for continuous use, a number of parallel compartments are provided to handle flow when one compartment is shut off for cleaning.  [c.403]

Because double-base propeUants cannot be directly bonded to the waUs of a rocket motor to maximize the propeUant weight in the motor, an adhesive resin is sprayed into the interior while the motor is rotated. A smaU amount of casting powder may also be sprayed into the tacky resin. The liner is cured and becomes an integral part of the propeUant charge after casting. The motor is fitted with the requited casting attachments, placed in a casting pit if necessary, and the casting powder dispenser and associated equipment are instaUed. The casting powder flows from a hopper through a distributor screen and a screen plate to disperse the powder uniformly into the motor. A high velocity air stream may also be used to carry the powder into the motor.  [c.47]

Ammonia and Hydrogen Production. The earliest route for manufacture of ammonia from nitrogen was the cyanamide process commercialized in Italy in 1906. In this process calcium carbide manufactured from coal was treated with nitrogen at 1000°C to form calcium cyanamide, CaCN2. The cyanamide was hydrolyzed with water affording ammonia and calcium carbonate. Production reached 140,000 t/yr in Germany in 1915, but this process was energy intensive and soon was displaced by the more efficient Bosch-Haber process. This process was developed by BASE and commercialized in 1913 and involves the high pressure reaction of nitrogen and hydrogen over an iron catalyst. Most of the world s hydrogen production is used in ammonia synthesis by the Bosch-Haber process. The hydrogen for ammonia synthesis generally is obtained from synthesis gas produced by steam  [c.164]

Essentially all the processes employed for ammonia synthesis are variations of the Haber-Bosch process developed in Germany from 1904—1913. One of the all-time breakthroughs of chemical technology, the synthesis process involves the catalytic reaction of a purified hydrogen—nitrogen mixture under high (14 to 70 MPa (2,030 to 10,150 psi)) pressure and temperature (400 to 600°C). The preferred catalysts consist of specially activated iron. The ammonia that forms is condensed by cooling with Hquefied ammonia the unreacted gases are recycled to the synthesis loop. In over 80% of the ammonia plants of the 1990s, the hydrogen—nitrogen feed mixture is prepared by a series of reactions known as steam reforming, for which the raw materials are steam, natural gas (methane), and air. Commercial plants have also been based on use of naphtha or coal (coke) as feedstock. AH facets of ammonia production are highly sophisticated engineering processes requiring both a high level of technical know-how and a large capital investment.  [c.216]

The U.S. industry sold about 2.92 biUion in 1992. More than 60% of these sales were made by the top 10 producers. In order of size these were SunChemical, Elint Ink, INX, BASE, Zeneca, The Ink Co., Huber, Superior, Siegwerk, and Crown ZeUerbach. These companies represent only 4% of the total number of ink companies in the United States.  [c.254]

The large values of maximum energy product and coercivity of the rare-earth magnets permit use in devices where small size and superior performance are desired (62). Magnets for electronic wristwatches and for traveling-wave tubes are largely made of rare-earth alloys. There are medical device appHcations which make use of the RCo and R2Co2y-base alloys. The temperature coefficient of polarization, which is typically —0.04%/°G, is too high for precision appHcations, such as gyros and accelerometers. However, polarization of the heavy RCo compounds, eg, Co Dy, increases with temperature at ca 25°C. When these rare earths are mixed with Sm, the temperature coefficient can be reduced by partially replacing the Sm with a heavier rare earth such as Dy.  [c.381]

SpiralTlevator Materials are moved upward by the centrally located spiral-type conveyor in a cylindrical or cone-shaped Nautamix vessel (Fig. 37c and d). Blending occurs by the downward movement at the outer walls of the vessel. The vessel serves the dual purposes of blending and storage. In these mixers the screw impeller actively agitates only a small portion of the mixture and natural circulation is used to ensure all the mixture passes through the impeller zone. In the case of Nautamix, an Archimedian screw lifts powder from the base of a conical hopper while progressing around the hopper wall.  [c.439]


See pages that mention the term Haber and Bosch : [c.67]    [c.269]    [c.150]    [c.497]    [c.74]    [c.157]    [c.161]    [c.37]    [c.37]    [c.407]   
Turboexpanders and Process Applications (0) -- [ c.86 ]