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Operational Changes

In the active picture adopted here the (X,Y,Z) axis system remains fixed in space and a translational synnnetry operation changes the (X,Y,Z) coordinates of all nuclei and electrons in the molecule by constant amounts, (A X, A Y, A Z) say,... [Pg.162]

The Raising and Lowering Operators Change the Jz Eigenvalue but not the J2 Eigenvalue When Aeting on j,m>... [Pg.620]

The carbon content of DRI depends primarily on the direct reduction process used and the way the process is operated. Carbon content can be adjusted within limits by operating changes within the DR process. Most steelmakers prefer slightly more carbon than is required to balance the remaining FeO in the DRI. DRI from gas-based processes typically contains 1 to 2.5% carbon, mostly in the form of cementite [12169-32-3] Fe C. DRI containing approximately 6 to 7% carbon in the form of cementite is called iron carbide. DRI from coal-based, rotary-kiln processes contains very low (ca 0.5%) levels of carbon. [Pg.425]

Each plant or laboratory should adopt definite rules and procedures for electrical iastahations and work. All iastahations should be ia accordance with the National Electrical Code (NEC) for the type of ha2ard, eg. Class I flammable gas or vapor Class II organic, metallic, or conductive dusts and Class III combustible fibers and the degree of process containment, eg. Division 1 open and Division 2 closed (67). Regardless of the flammabiUty of the materials ia the iastaHed operations, changes ia procedure involving use of such materials often occur, sometimes without concurrent alteration of the electrical iastaHation. [Pg.98]

When tank operators change a stored hquid, care must be exercised. If there is a significant increase in the specific gravity of the new hquid, the effective hydrostatic pressure acting on the tank walls is greater if the design hquid level is not reduced. [Pg.309]

When steam blanketing is occurring, corrosion can take place even without the presence of caustic, due to the steam—magnetite reaction and the dissolution of magnetite. In such cases, operational changes or design modifications may be necessary to eliminate the cause of the problem. [Pg.264]

Sources Subject to Prevention of Significant Deterioration (PSD) Sources subject to PSD regulations (40 CFR, Sec. 52.21, Aug. 7, 1980) are major stationary sources and major modifications located in attainment areas and unclassified areas. A major stationaiy source was defined as any source hsted in Table 25-4 with the potential to emit 100 tons per year or more of any pollutant regulated under the Clean Air Act (CAA) or any other source with the potential to emit 250 tons per year or more of any CAA pollutant. The potential to emit is defined as the maximum capacity to emit the pollutant under apphcable emission standards and permit conditions (after apphcation of any air pollution control equipment) excluding secondaiy emissions. A major modification is defined as any physical or operational change of a major stationaiy source producing a significant net emissions increase of any CAA pollutant (see Table 25-5). [Pg.2156]

Assuming = 0 will potentially add bias to the interpretation of plant measurements. Further, the plant bias may to some extent mask the error in the measurements. While the designer may have envisioned a constant set of conditions or a specified time dependence, it is likely that the actual operation changes due to external factors. [Pg.2562]

Recommendations were made to begin treatment with corrosion inhibitors and to make system operation changes to reduce grease and oil fouling. Other water chemistry recommendations involved reducing the amount of aggressive anion in solution and pursuing biocidal treatment. [Pg.59]

Water chemistry and operating changes were suggested but were deemed inadvisable because of legal restrictions concerning discharge of chemicals into local waters. [Pg.64]

In summary, for each alternate operation, an approximate net effect or set of effects can be quickly built into the Smith-Brinkley input to determine new end compositions. The instrumentation scheme will affect the result produced by an operating change. [Pg.71]

This fourth criterion can be met at a low steam drum cost. Only one percent of the cost of the boiler spent on the steam drum can provide it. The fourth criterion is met by requiring that the Drum-Level-Stability Factor (D.L.S.F.) be equal to 1.0 minimum. When this exists the steam drum level will be stable for wide and sudden operational changes. [Pg.143]

While a single, low pressure compressor may require little or no treatment for pulsation control, the same machine with an increased gas density, pressure, or operational changes may develop a problem with pre, sure pulses or standing wave performance deterioration. As un installation becomes more complex, such as with an increase in the number of cylinders connected to one header and the use of multiple stages the possibility of a problem can increase. [Pg.84]

Source reduction includes any in-plant actions to reduce the quantity or the toxicity of the waste at the source. Examples include equipment modification, design and operational changes of the process, reformulation or redesign of products, substitution of raw materials, and use of environmentally benign chemical reactions. [Pg.2]

Most than 500 plant design or operation improvements were identified by licei " of the improvements were procedural/operational changes 40% were design/hardware c ew... [Pg.394]

To deal with all kinds of normal distributions of different means and variances, the cumulative distribution is further normalized. This introduces a new variable u = x - ix)/(t. This operation changes a N(p, a) distribution to a N(0, 1) distribution. From Eq. (12.3) the following is obtained ... [Pg.1126]

The standard also requires that the instructions be derived from appropriate sources, such as the quality plan, the control plan, and the product realization process, which means that all instructions should be traceable to one or more of these documents. They should form a set, so that there are no instructions used outside those that have been approved by the planning team. This is to ensure that no unauthorized practices are employed. Another important aspect to consider is the use of informal practices - practices known only to the particular operator. Process capability should be based on formal routines, otherwise repeatability cannot be assured when operators change. [Pg.354]

Prior to a mechanical upgrade, the refiner must ensure that, given existing mechanical limitations, the unit s performance has reached its full potential with catalyst and operational changes. It is much easier to determine the effects of the mechanical upgrade with a well-... [Pg.207]

At steady-state condition for chemostat operation, change of concentration is independent of time. Material balance for the fermentation vessel is ... [Pg.89]

For nondegenerate vibrations all symmetry operations change Qj into 1 times itself. Hence Q/ is unchanged by all symmetry operations. In other words, Q and consequently y(O) behave as totally symmetric functions (i.e. the function is independent of symmetry). However, the wavefunction of the first excited state 3(1) has the same symmetry as Qj. For example, the wavefunction of a totally symmetric vibration (e.g. Qi of C02) is itself a totally symmetric function. [Pg.340]

For larger plants some water analysis, results interpretation, and recommendations for operational changes may be carried out by a boiler operator, water treatment plant technician or a laboratory analyst (or even by an outsourced subcontractor) these recommendations complement similar work undertaken by the water treatment service company representative. [Pg.125]

An operational change because caustic concentration typically results when high-firing cycle operations permit departure from nucleate boiling (DNB) to occur... [Pg.157]

Structural, cultural, strategic or operational changes as a result of the above. [Pg.51]

The operator Tang contains the cross-terms that give rise to the Coriolis coupling that mixes states with different fl (the projection of the total angular momentum quantum number J onto the intermolecular axis). This term contains first derivative operators in y. On application of Eq. (22), these operators change the matrix elements over ring according to... [Pg.21]


See other pages where Operational Changes is mentioned: [Pg.614]    [Pg.370]    [Pg.370]    [Pg.518]    [Pg.181]    [Pg.74]    [Pg.225]    [Pg.718]    [Pg.1233]    [Pg.2172]    [Pg.306]    [Pg.352]    [Pg.10]    [Pg.24]    [Pg.11]    [Pg.12]    [Pg.398]    [Pg.286]    [Pg.312]    [Pg.24]    [Pg.104]    [Pg.447]    [Pg.171]    [Pg.324]    [Pg.199]    [Pg.41]    [Pg.323]   


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