Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Facilities extension

A 1,5 sigmatropic shift is symmetry allowed and occurs suprafacially with the migrating group staying on the same side of the molecule, as shown in Figure 4.10. This process should be facile. Extensions to larger systems follow in an obvious way and predict that 1,7 shifts should be antarafacial and 1,9 shifts suprafacial. [Pg.134]

Speckle shearing interferometry, or shearography, is a full field optical inspection teclmique that may be used for the nondestructive detection of surface and, sometimes, subsurface defects. Whilst being more sensitive in the detection of surface defects, it may also be considered for pipe inspection and the monitoring of internal conoslon. In contrast, laser ultrasound and other forms of ultrasound, are point by point measurement techniques, so that scanning facilities and significant data processing is required before information on local defects is extracted from any examination of extensive areas [1 - 3]. [Pg.678]

The vast majority of commercial apphcations of methacryhc acid and its esters stem from their facile free-radical polymerizabiUty (see Initiators, FREE-RADICAl). Solution, suspension, emulsion, and bulk polymerizations have been used to advantage. Although of much less commercial importance, anionic polymerizations of methacrylates have also been extensively studied. Strictiy anhydrous reaction conditions at low temperatures are required to yield high molecular weight polymers in anionic polymerization. Side reactions of the propagating anion at the ester carbonyl are difficult to avoid and lead to polymer branching and inactivation (38—44). [Pg.247]

Testing, certification, and installation rules for reheving devices are extensive. Eveiy chemical engineer responsible for the design or operation of process units should become veiy familiar with these rules. The pressure-relief-device paragraphs are the only parts of Sec. TII, Division I, that are concerned with the installation and ongoing operation of the facility all other rules apply only to the design and manufacture of the vessel. [Pg.1024]

A wet-process plant maldug cement from shale and hmestoue has been described by Bergstrom [Roc/c Prod., 64—71 (June 1967)]. There are separate facilities for grinding each type of stone. The ball mill operates in closed circuit with a battery of Dutch State Mines screens. Material passing the screens is 85 percent minus 200 mesh. The entire process is extensively instrumented and controlled by computer. Automatic devices sample crushed rock, slurries, and finished product for chemical analysis by X-rav fluorescence. Mill circuit feed rates and water additions are governed by conventional controllers. [Pg.1871]

B) Any contamination of the environment or damage to natural resources at a facility owned or operated hy Seller or a facility/location chosen hy Seller for its disposal of Wastes or any other facility at which Seller s Wastes may he released or threatened to he released, including any liability imposed by federal, state and local laws, regulations and ordinances, including, but not limited to, the Federal Comprehensive Environmental Response Compensation and Liability Act (CERCLA), 42 USC 9601 etseq., the Federal Resource Conservation and Recovery Act (RCRA), 42 USC 6901 et seq., or comparable and applicable state legal requirements or any extension or revision thereof or... [Pg.73]

If a PSSR is extensive, the PSSR team should include a toller company engineer and an engineer from the client. In addition, an operations supervisory representative and operations personnel with appropriate knowledge and skills along with a maintenance and safety representative may also be included on the team. The PSSR leader must ensure enough manpower and expertise is available on the team to review the new facilities and major modifications thoroughly. [Pg.97]

Emissions from other nonferrous metal facilities are primarily metal fumes or metal oxides of extremely small diameter. Zinc oxide fumes vary from 0.03 to 0.3 jiim and are toxic. Lead and lead oxide fumes are extremely toxic and have been extensively studied. Arsenic, cadmium, bismuth, and other trace metals can be emitted from many metallurgical processes. [Pg.88]

The U.S. government is promoting poUution prevention at feder2d facilities. Cooperating with the EPA are the U.S. Departments of Agriculture, Defense, Energy, Interior, Transportation, Treasury, and Veterans Affairs. The U.S. Postal Service has also committed to an extensive pollution prevention program. [Pg.458]

For the environmental consultant, an extensive overview of corrective action technologies is provided. Topics covered are the general concepts of corrective action programs, facility investigation principles, treatment technologies for wastes and waste streams, post treatment technologies and engineering considerations for corrective measures implementation. [Pg.320]

Requirements for desulfurizing the feed are much the same as in the semi-regenerative process. While the continuous regeneration facilities would permit operation with higher sulfur feeds, extensive HjS corrosion results, making feed... [Pg.56]

The use of dimethyl sulfoxide-acetic anhydride as a reagent for the oxidation of unhindered steroidal alcohols does not appear to be as promising due to extensive formation of by-products. However, the reagent is sufficiently reactive to oxidize the hindered 11 j -hydroxyl group to the 11-ketone in moderate yield. The use of sulfur trioxide-pyridine complex in dimethyl sulfoxide has also been reported. The results parallel those using DCC-DMSO but reaction times are much shorter and the work-up is more facile since the separation of dicyclohexylurea is not necessary. Allylic alcohols can be oxidized by this procedure without significant side reactions. [Pg.238]

Table 14-5 shows symbols used in RP 14C to represent the various sensors and shutdown devices. Although these symbols are used extensively in U.S. production facilities, they are not used in other indusiries. They are widely used overseas and are understood by all who are involved in production facility design. In other countries and other industries, the ISA symbol system is more common. [Pg.410]

A fire in a bulk storage facility at Coode Island, Melbourne, Australia, in August 1991 caused extensive damage and many complaints about the pollution caused by the smoke plume, but no injuries. The tank vents were connected together and piped to a carbon bed vapor recovery system. There were no flame arrestors in the pipework. Whatever the cause of the initial fire or explosion, the vent collection system provided a means of spreading the fire from one tank to another. [Pg.72]

Alkylation of enamines can take place on carbon or on nitrogen (see Section I). The theoretical considerations and reaction conditions which determine whether C or N alkylation takes place have already been studied extensively 26-32). These studies have shown that the facility with which alkylation takes place depends on the basicity of theenamine, on the ease of formation of a trigonal atom in the transition state, and on the nature of the enamine, the alkylating agent, and the solvent. [Pg.119]

Historical data are used for facility types where tliere is extensive experience available from similar or identical installations. [Pg.516]

An extensive derivative chemistry of the icosahedral carboranes has been developed, especially for l,2-C2BioHi2. Terminal H atoms attached to B undergo facile electrophilic substitution and the sequence of reactivity follows the sequence of negative charge density on the BHt group ... [Pg.186]

The most notable chemistry of the biscylopen-tadienyls results from the aromaticity of the cyclopentadienyl rings. This is now far too extensively documented to be described in full but an outline of some of its manifestations is in Fig. 25.14. Ferrocene resists catalytic hydrogenation and does not undergo the typical reactions of conjugated dienes, such as the Diels-Alder reaction. Nor are direct nitration and halogenation possible because of oxidation to the ferricinium ion. However, Friedel-Crafts acylation as well as alkylation and metallation reactions, are readily effected. Indeed, electrophilic substitution of ferrocene occurs with such facility compared to, say, benzene (3 x 10 faster) that some explanation is called for. It has been suggested that. [Pg.1109]

Elements beyond 103 are expected to be 6d elements forming a fourth transition series, and attempts to synthesize them have continued during the past thirty years. All 10 (including, of course, actinium) are now known and are discussed in the section on transactinide elements on p. 1280. The work has required the dedicated commitment of extensive national facilities and has been carried out at the Lawrence-Berkeley Laboratories, the Joint Institute for Nuclear Research at Dubna, and the Heavy-Ion Research Centre (GSI) at Darmstadt, Germany. [Pg.1253]

In some molecules, the loss of halogen is unexpectedly facile and may occur extensively even over platinum, as illustrated by reduction of the dihydro-2-benzazepine 4 to 5. The authors (5i) raised the possibility that such facile loss of halogen may involve neighboring-group assistance from the amide moiety. [Pg.149]


See other pages where Facilities extension is mentioned: [Pg.19]    [Pg.43]    [Pg.1162]    [Pg.230]    [Pg.19]    [Pg.43]    [Pg.1162]    [Pg.230]    [Pg.56]    [Pg.119]    [Pg.229]    [Pg.296]    [Pg.45]    [Pg.472]    [Pg.857]    [Pg.1019]    [Pg.1104]    [Pg.1743]    [Pg.2421]    [Pg.131]    [Pg.96]    [Pg.22]    [Pg.29]    [Pg.73]    [Pg.88]    [Pg.5]    [Pg.77]    [Pg.84]    [Pg.330]    [Pg.35]    [Pg.324]    [Pg.432]    [Pg.50]    [Pg.20]    [Pg.513]   
See also in sourсe #XX -- [ Pg.51 , Pg.124 , Pg.125 , Pg.126 , Pg.127 , Pg.128 , Pg.129 , Pg.130 , Pg.131 , Pg.132 , Pg.133 , Pg.134 ]




SEARCH



© 2024 chempedia.info