Jack bean


Urease soya bean, jack bean urea ammonium carbonate 7-2-7 9  [c.511]

Urease is one of the enzymes which have been obtained in the crystalline state. This has been done by stirring jack bean meal with 30°o aqueous acetone, filtering and allowing the filtrate to remain at o for several hours. The urease which crystallises out is separated by centrifuging and is then recrystallised. Like crystalline pepsin and trypsin, it is a protein.  [c.519]

Place about 0 2 g. of jack-bean meal in a test-tube, add 2 ml. of water and about 5 drops of phenol-red. Mix thoroughly and allow the faintly yellow solution to stand while the urea solution is being made up.  [c.519]

Urease solution. Place about 5 g. of jack-bean meal in a mortar and grind up with about 10 ml. of water, t hen add about 90 ml. of water, mix thoroughly and allow to stand for some time in order to deposit starch and other insoluble substances. Decant off the supernatant liquid into a conical flask and cork the latter.  [c.520]

Crease soya bean, jack bean urea ammonium carbonate 7 2-7 9  [c.511]

Urease is one of the enzymes which have been obtained in the crystalline state. This has been done by stirring jack bean meal with 30°i aqueous acetone, filtering and allowing the filtrate to remain at 0° for several hours. The urease which crystallises out is separated by centrifuging and is then recrystallised. Like crystalline pepsin and trypsin, it is a protein.  [c.519]

Place about 0-2 g. of jack-bean meal in a test-tube, add 2 ml. of water and about 5 drops of phenol-red. Mix thoroughly and allow the faintly yellow solution to stand while the urea solution is being made up.  [c.519]

Urease solution. Place about 5 g. of jack-bean meal in a mortar and grind up with about 10 ml. of water. I hen add about 90 ml. of water, mix thoroughly and allow to stand for some time in order to deposit starch and other insoluble substances. Decant off the supernatant liquid into a conical flask and cork the latter.  [c.520]

Until the discovery in 1975 of nickel in jack bean urease (which, 50 years previously, had been the first enzyme to be isolated in crystalline form and was thought to be metal-free) no biological role for nickel was known. Ureases occur in a wide variety of bacteria and plants, catalyzing the hydrolysis of urea,  [c.1167]

Drilling Jackets are small steel platform structures which are used in areas of shallow and calm water. A number of wells may be drilled from one jacket. If a jacket is too small to accommodate a drilling operation, a jack-up rig (see below) is usually cantilevered over the jacket and the operation carried out from there. Once a viable development has been proven It is extremely cost effective to build and operate jackets in a shallow  [c.32]

Secondary Treatments and Uses. Particleboards are the jack-of-all-trades products for interior use panels. They have been and are being used for virtually every conceivable interior use for which panels or strips of material can be used. The principal desirable features of particleboards are flat, smooth, warp-free, stable, and cost-efficient panels. They have good strength, stability, and screw and fastener holding abilities. They are almost ideal substrates for most finishing or overlay systems. They are available in many thicknesses and panel sizes and can be easily worked with good wood-cutting, mol ding, shaping, drilling, and vee-grooving equipment. To put their versatility into the perspective that is their due, it would be safe to say that the vast majority of homes and businesses in the United States contain a number of products in which the basic substrate is particleboard.  [c.393]

Food Enzymes. The source of a food enzyme determines its primary regulatory status. Traditionally, enzymes from edible parts of plants and animals, eg, papain from papaya and chymosin from calf stomach, have been accepted for food use without further evaluation. Although a few plant and animal enzymes still find industrial uses, the majority of food enzymes are produced by fermentation of microorganisms. Three categories of microorganisms have been defined by JECEA for regulatory purposes (/) those considered to be food stuffs, such as yispergillus OTj e the most prominent example of this category 2) those considered harmless contaminants of food, such as A.spergillus niger bacillus suhtilis bacillus licheniformis and Saccharomyces cerevisiae and (J) all other microorganisms.  [c.304]

Product specifications for microbial food enzymes have been estabUshed by JECEA and ECC. They limit or prescribe the absence of certain ubiquitous contaminants such as arsenic, heavy metals, lead, coliforms, E. coli and Salmonella. Furthermore, they prescribe the absence of antibacterial activity and, for fungal enzymes only, mycotoxins.  [c.304]

From 1924 to 1927, Jack Johnson served as instmctor in organic chemistry at the University of Illinois (Urbana) Besides teaching and directing research problems for seniors and graduate students he collaborated with Roger Adams in publishing Elementary Laboratory Experiments in Organic Chemistry It was first published in 1928 and had many revisions This book, now in its 7th edition, has been edited in recent years by Charles F Wilcox, one of Johnson s colleagues at Cornell University, Adams and Johnson was as well known in the U S A as the classic Gatterman-Wieland  [c.222]

The chief sources of this important enzyme are (a) the jack bean (Canavalia ensiformis). (b) the soy (or soja) bean (Glycine hispida). The enzyme is of great value in identifying and estimating urea. The action of urease on urea is specific, the reaction catalysed being  [c.519]

Lrease test. The enzyme urease hydrolyses urea to ammonium carbonate (p. 519). The reaction is sp" tific and is frequently used for solutions of urea to which the biuret test cannot be applied. Add about 5 drops of phenol-red to o-z g. of urea dissolved in 5 ml. of water. To this yellow solution, add o-z g. of jack bean meal suspended in z ml. of water containing. also 5 drops of phenol-red. The colour changes to red as the solution becomes alkaline.  [c.363]

The chief sources of this important enzyme are (a) the jack bean Canavalia ensiformii), (b) the soy (or soja) bean (Glycine hispida). The enzyme is of great value in identifying and estimating urea. The action of urease on urea is specific, the reaction catalysed being  [c.519]

The analysis is thus relatively exact for heterogeneous surfaces and is especially valuable for analyzing changes in an adsorbent following one or another treatment. An example is shown in Fig. XVII-24 [160]. This type of application has also been made to carbon blacks and silica-alumina catalysts [106a]. House and Jaycock [161] compared the Ross-Olivier [55] and Adamson-Ling  [c.658]

Such large-scale modelling experiments can require significant computational resources, but the main bottleneck is generally considered to be the absence of structurally defined members of many protein families and the difficulty in detecting weak similarities, which would enable the appropriate template structures to be identified for more detailed comparative modelling. Above all, it is important to remember that no one single theoretical or experi-mejital technique can predict protein function from sequence rather, it is the application of an appropriate combination of methods that is required. Moreover, although our emphasis has been on the importance of the three-dimensional structure, such information is only one part of the jigsaw. An illustration is provided by a study which compared all of the protein structures released in 1998 with all structures that were known by the end of 1997 I Koppensteiner et al. 2000]. Some 147 of the proteins (corresponding to 196 domains) solved in 1998 had no significant sequence similarity to any of the pre-1998 proteins. Flow-ever, when the structures of these 196 domains were compared with the pre-1998 set it was found that 147 of the domains had significant structural similarity with a previously known protein fold. Moreover, in two-thirds of these cases the function was also the same. The implication from these and similar studies is that computational techniques can be very effective at processing and filtering the raw sequence information in order to identify proteins that may be of interest and thus to suggest what experiments should be performed in order to confirm the hypothesis.  [c.565]

An important class of adsorbents, which unlike xenon are solid at room temperature and are therefore more commonly encountered in practice, are ionic crystals. They are, however, rather more complex, not only on account of the presence of more than one type of atom (ion) but also because electrostatic forces are involved alongside the dispersion forces. To avoid the further complications arising from different possible orientations of the molecule relative to the surface, most workers have again chosen an inert gas as adsorptive. A number of studies have been made along these lines. Recently, for example, House and Jaycock have made very detailed calculations, involving lattice summations over 3000 nearest atoms of the solid, for the adsorption of He, Ne, Ar, Kr and Xe on the (100) face of NaCl and also of Aron the (100) face of KCl electrostatic contributions were also taken into account. From the resultant contour maps for the overall interaction energy (f>Q, it is found that the energy barrier to translational movement along the surface is 3-81 kJmol for Xe on NaCl, hut only 0-53 kj mol" for Ar on KCl. Thus the adsorption of xenon on NaCl at 60 K, where RT is 0-50kJ mol" , should be localized (this has been confirmed hy low-energy electron diffraction) but that of Ar on NaCl at the same temperature should be non-localized.  [c.10]

Short Life Tests. To cause thick-walled cylinders to fail in less than 10 cycles, larger internal pressures than those generated by the Bristol machine are required and low cycle, high stress fatigue studies are usually carried out by piping pressure from an intensifier to the component or components under test (99). When the set pressure is reached, a valve is opened and the pressure drops to near atmospheric after which the cycle is repeated. Alternatively, the intensifier is used as a jack to reciprocate a ram within an od-filled space (88,100). About 10—20 cycles per min can be achieved using an hydraulic drive, but pressures of 1 GPa (145,000 psi) can be achieved in specimens of small volume (99) or 300 MPa (43,500 psi) in vessels having a bore of 300 mm (100, 101). The ha2ards and safeguards of fatigue tests on large vessels have been reported (102).  [c.90]

MO Media Summary. When compared to magnetic recording on hard disks, the advantage of MO data storage is the removabiUty of the disks and the high storage capacity (especially on multiplatter (juke-box) systems) whereas the access times have not yet been reached.  [c.148]

Sulfur and its compounds are among the oldest and most widely used pesticides. Elemental sulfur is especially effective as a dust for the control of mites attacking citms, cotton, and field crops and as a protectant against chiggers, Trombicula spp., attacking humans. Sulfur also is a valuable fungicidal diluent for other dust insecticides and is used in wettable form as a spray mixture. Time sulfur has been a standard dormant spray for the control of the San Jose Quadraspidiotuspemiciosus and for other scales and various plant diseases. Time sulfur is a water-soluble mixture of calcium pentasulfide,  [c.269]

Design variables introduced on various prostheses represent efforts to share the stresses and normal loading characteristics of human locomotion. The size, shape, and tissue stmcture of bone are most commonly affected in the healing of fractures. Bone remodeling was first described in 1892 by the German physician Juhus Wolff in The Taw of Bone Transformation. In terms of force loading and stresses, Wolff s law states that bone responds to mechanical demends by changing its size, shape, and stmcture.  [c.189]

Congenital deficiency of Factor XI is a relatively rare coagulopathy that has been reported as both an autosomal dominant and autosomal recessive trait. This deficiency state occurs predominantly in the Jewish population. Most patients with this deficiency state remain asymptomatic until trauma or surgery is encountered. Spontaneous hemorrhage is rare in this population.  [c.174]

In 1826 Antoine-Jerome Balard ia France pubUshed the discovery of bromine which was isolated by chlorinating seawater bitterns and distilling out bromine. Bromine had been prepared earlier by Joss and Liebig but neither of them recognized it as an element (1). Bromine was used ia photography ia about 1840. The first medical use was ia 1857 when bromides were used for the treatment of epilepsy. The first commercial bromine production ia the United States was ia 1846 at Freeport, Peimsylvania. In 1858 potash was discovered ia the Stassfurt salt deposits ia Germany and bromine was a by-product. Herbert Dow iavented the "blowiag out" process for Midland (Michigan) brines ia 1889. The antiknock properties of tetraethyl lead [78-00-2], (CH2CH2)4Pb, were discovered ia 1921 and soon after ethylene dibromide [106-93-4], C2H4Br2, was found to aid the removal of lead from combustion chambers. At one time about 80% of all bromine was used to produce ethylene dibromide. Bromine was first commercially extracted from seawater ia 1934. In the 1950s bromine was discovered ia south Arkansas briaes, the only significant source of bromine ia the United States (see Chemicals FROM brine).  [c.278]

Specifications. EZ compounds meet class EK in the SAE automotive mbber classification J200. Line callouts have been developed for 50, 70, and 80 durometer materials. Specific compounds meet requirements for O-rings for military aerospace appHcations identified in MIL-P-87175,  [c.528]

The area of bio transformations has experienced a phenomenal growth ia recent years as judged by the number of pubHcations. In addition to the fermentation technology that has been utilized for years for the production of molecules varying from ethanol and vitamins to amino acids and steroids, the practical use of isolated enzymes as catalysts ia organic synthesis has started to achieve great prominence. This phenomenon has been brought about by a number of factors. In response to an ever-growing demand for new biocatalysts, more enzymes have become available in recent years. Such primary supphers as Amano, Genencor, Novo, Meito Sangyo, Toyo Jozo, Rhc ne-Poulenc, Serva, Nagase, Tanabe, Boehringer-Mannheim, and others now trade dozens of enzymes, many in ton quantities. Moreover, advances in molecular biology and genetic engineering have resulted in new enzymes with altered specificity and increased stabiUty. For example, highly stable subtilisin mutants with an increased propensity for peptide condensation (184) have been constmcted and successfully used for peptide synthesis (135). A modified lactate dehydrogenase that is specific for new substrates and lacks allosteric regulation (185) has been used for enantioselective reductions (173).  [c.350]

Since s and e are symmetric, = t-jiki = tyik- Since (5.3) has been assumed to be invertible in , c is nonsingular. Note that (5.4) may be written as  [c.123]

In 1958-1959, two American inventors, Jack Kilby and Robert Noyce, men cast in the mould of Edison, independently found a way around this problem. Kilby had joined the new firm of Texas Instruments, Noyce was an employee of another young company, Fairchild Electronics, which William Shockley had founded when he resigned from Bell but mismanaged so badly that his staff grew mutinous Noyce set up a new company to exploit his ideas. The idea was to create a complete circuit on a single small slice of silicon crystal (a chip ), with tiny transistors and condensers fabricated in situ and with metallic interconnects formed on the surface of the chip. The idea worked at once, and triumphantly. Greatly improved reliability was the initial objective, but it soon became clear that further benefits flowed from miniaturisation (1) low power requirements and very small output of waste heat (which needs to be removed) (2) the ability to accommodate complex circuitry, for instance, for microprocessors or computer memories, in tiny volumes, which was vital for the computers in the Apollo moonlanding project (Figure 7.3) and, most important of all, (3) low circuit costs. Ever since Kilby s and Noyce s original chips, the density of devices in integrated circuits has steadily increased, year by year, and the process has still not reached its limit. The story of the invention and early development of integrated circuits has been well told in a book by Reid (1984). Some of the relatively primitive techniques used in the early days of integrated circuits are described in a fascinating review which covers many materials aspects of electronics and communications, by Baker (1967) who at the time was vice-president for research of Bell Laboratories. Kilby has at last (2000) been awarded a Nobel Prize.  [c.262]

I am grateful to several reviewers and commentators for uncovering misprints, omissions and factual errors which I have been able to correct in this printing. My thanks go especially to Masahiro Koiwa in Japan, Jean-Paul Poirier and Jean Philibert in France, Jack Westbrook and Arne Hessenbruch in the United States.  [c.582]

Today many of the projected benefits of MF and UF have been realized. These technologies provide effective disinfection for potable water supplies as they reduce the levels of Giardia and Cryptosporidium, as well as a variety of bacteria, below detectable levels. MF and UF plants are now in operation throughout the world. In Europe there are several large UF plants. In the U.S., the San Jose Water Co. in Saratoga, Calif., was the first to construct a major MF plant (17,000 mVday). A plant with 15,000 mVday capacity followed in Rancho Cucamonga, Calif., and a 68,000 mVday plant is under construction in Kenosha, Wisconsin. The largest plant for disinfection and particle removal, a 106,000 mVday UF installation, is being planned in Del Rio, Tex. Today, there is more than 400,000 m /day of MF and UF capacity in the U.S., either in operation or in the planning stage.  [c.357]

An important class of adsorbents, which unlike xenon are solid at room temperature and are therefore more commonly encountered in practice, are ionic crystals. They are, however, rather more complex, not only on account of the presence of more than one type of atom (ion) but also because electrostatic forces are involved alongside the dispersion forces. To avoid the further complications arising from different possible orientations of the molecule relative to the surface, most workers have again chosen an inert gas as adsorptive. A number of studies have been made along these lines. Recently, for example, House and Jaycock have made very detailed calculations, involving lattice summations over 3000 nearest atoms of the solid, for the adsorption of He, Ne, Ar, Kr and Xe on the (100) face of NaCl and also of Ar on the (100) face of KCI electrostatic contributions were also taken into account. From the resultant contour maps for the overall interaction energy it is found that the energy barrier to translational movement along the surface is 3-81 kJmoP for Xe on NaCI, but only 0-53 kj mol for Ar on KCI. Thus the adsorption of xenon on NaCl at 60 K, where RT is O-SOkJmoP, should be localized (this has been confirmed by low-energy electron diffraction) but that of Ar on NaCl at the same temperature should be non-localized.  [c.10]

As its name implies, fines destruetion involves seleetively withdrawing a slurry stream eontaining fine erystals (Figure 7.4). These tiny erystals are then redissolved, e.g. by heating or addition of fresh solvent, and the solute returned to the erystallizer. In this way, the working level of supersaturation is inereased giving rise to inereased growth rates but lower effeetive nueleation rates. Thus, fewer erystals share the available solute, whieh leads to an inerease in mean partiele size and a tightening of the size distribution in the small erystal region (Figure 7.10). This teehnique is employed industrially and has been studied experimentally by Jazaszek and Larson (1977) and Randolph et al. (1977), respeetively.  [c.210]


See pages that mention the term Jack bean : [c.363]    [c.428]    [c.717]    [c.110]    [c.249]    [c.152]    [c.193]    [c.84]    [c.149]    [c.378]    [c.531]    [c.152]    [c.325]   
Practical organic chemistry (1960) -- [ c.363 , c.519 , c.520 ]

Practical organic chemistry (1978) -- [ c.363 , c.519 , c.520 ]