Primary difference

In summary then the chlorination of alkanes is not very selective The various kinds of hydrogens present m a molecule (tertiary secondary and primary) differ by only a factor of 5 m the relative rate at which each reacts with a chlorine atom... 

As a result of these considerations, the primary difference between a spectrophotometer and a light-scattering photometer is the fact that the photodetector is mounted on an arm which pivots at the sample so that intensity measurements can be made at various angles. 

The choice of technology, the associated capital, and operating costs for a chlor—alkaU plant are strongly dependent on local factors. Especially important are local energy and transportation costs, as are environmental constraints. The primary difference ia operating costs between diaphragm, mercury, and membrane cell plants results from variations ia electricity requirements for the three processes (Table 25) so that local energy and steam costs are most important. 

The primary difference in shale oils produced by different processing methods is in boiling point distribution. Rate of heating, as well as temperature level and duration of product exposure to high temperature, affect product type and yield (28). Gas combustion processes tend to yield slightly heavier hquid products because of combustion of the lighter, ie, naphtha, fractions. 

Process Technology Considerations. Innumerable complex and interacting factors ultimately determine the success or failure of a given ethylene oxide process. Those aspects of process technology that are common to both the air- and oxygen-based systems are reviewed below, along with some of the primary differences. 

Aside from size considerations, the primary difference between bench-scale and pilot-scale work is that bench-scale tests are conducted in the laboratory pilot-scale testing is usually carried out on the site. Pilot tests are subject to a whole range of problems, such as siting, health and safety, obtaining clearances, installation and operation. However, the data obtained from pilot-scale tests are much more appropriate and useful because they reflect what is actually occurring in the field. 

Systems analyses are like formulas, they have little usefulness until the variables are assigned probabilistic numbers from nuclear or chemical data bases. These data concern the probability of failing vessels, pipes, valves, instruments and controls. The primary difference between chemical and nuclear data is that the former may operate in a more chemically active environment, while the later operate in radiation. This chapter addresses both, but most of the data were gathered for nuclear systems. It covers 1) failure rate databases, 2) incident databases, 3) how to prepare failure rates from incidents, and 4) human factors for nuclear and chemical analyses. 

Primary difference The difference between the primary air temperature and the reference air temperature in the reference zone. 

When purchasing GPC/SEC columns it is imperative to realize that no manufacturer has a technical edge on another. The products are analogous, with the primary difference being price. When one buys a GPC/SEC column, it is the service of gel preparation and column packing that is really purchased. We have provided the formulae and directions for the preparation of GPC gels because we do not want our customers to pay for a service that they themselves can do for less. 

The basic principles of rotary drilling defined for onshore operations are also applicable to offshore operations. The primary difference offshore is that a stable, self-contained platform must be provided for the drilling equipment. Communication with a well through possibly thousands of feet of water provides for mechanical as well as procedural differences, primarily in well control. Onshore technology can be applied to offshore operations in many instances on bottom-supported rigs, but the use of floating vessels has resulted in the development of new technology tailored to the offshore environment. 

The primary difference between transmission and distribution systems is one of pressure. Transmission systems operate at high pressures (>7bar) while distribution systems operate at low (<75 mbar) and medium (75 mbar to7 bar) pressures. The functions are also different in that the transmission system is used to convey gas over distances and store it, while the distribution system is used to convey gas to the user over a local network. The pipe that conveys gas from the main of the distribution system to the meter control valve of the user is the service. 

Raman spectroscopy can in principle be applied to this problem in much the same manner as infrared spectroscopy. The primary difference is that the selection rules are not the same as for the infrared. In a number of molecules, frequencies have been assigned to combinations or overtones of the fundamental frequency of the... 

The primary difference between these types of metal wastage and oxygen corrosion is that these are all indirect forms of attack, induced by surface shielding (areas of metal surface under deposits or foulants, or cracks and gaps in the metal that are close to a shielding surface). 

Electronic infusion devices are classided as either infusion controllers or infusion pumps. The primary difference between die two is diat an infusion pump adds pressure to die infusion, whereas an infusion controller does not. An infusion pump may be used to deliver the desired number of drops per minute. An alarm is set to sound if the IV is more than or less dian the preset rate... 

In differential scanning calorimetry (DSC), higher precision can be obtained and heat capacities can be measured. The apparatus is similar to that for a DTA analysis, with the primary difference being that the sample and reference are in separate heat sinks that are heated by individual heaters (see the following illustration). The temperatures of the two samples are kept the same by differential heating. Even slight... 

The kinetic models for the gas phase polymerization of propylene in semibatch and continuous backmix reactors are based on the respective proven models for hexane slurry polymerization ( ). They are also very similar to the models for bulk polymerization. The primary difference between them lies in the substitution of the appropriate gas phase correlations and parameters for those pertaining to the liquid phase. 

Before returning to the non-BO rate expression, it is important to note that, in this spectroscopy case, the perturbation (i.e., the photon s vector potential) appears explicitly only in the p.i f matrix element because this external field is purely an electronic operator. In contrast, in the non-BO case, the perturbation involves a product of momentum operators, one acting on the electronic wavefimction and the second acting on the vibration/rotation wavefunction because the non-BO perturbation involves an explicit exchange of momentum between the electrons and the nuclei. As a result, one has matrix elements of the form (P/ t)Xf > in the non-BO case where one finds lXf > in the spectroscopy case. A primary difference is that derivatives of the vibration/rotation functions appear in the former case (in (P/(J.)x ) where only X appears in the latter. 

This paper discusses the role that statistics can play In environmental sampling. The primary difference between an Investigation based on statistical considerations and one that Is not Is the degree of objectivity that can be Incorporated Into the evaluation of the quality and uncertainty of the study results. Statistical methods In the planning stage can also aid In optimizing allocation of resources. 

Confirmatory procedures are evaluated differently from determinative procedures because of the different intended uses of the procedure. The primary differences are the testing laboratories and evaluation of the resulting data. Because a confirmatory procedure is needed for legal action, the procedure will be evaluated based on the results obtained in a government laboratory. 

One of the primary differences between the FDA s and EPA s rules is the creation of the CDX. The EPA s OEI is currently developing the specifications for a CDX that will serve as the Agency s gateway for electronic documents received by the EPA. CROMERRR reports that with respect to the electronic document submission addressed by today s proposal, CDX functions will include the following ... 

Figures 9 and 10 represent a selected comparison of amide V and I+II FTIR and VCD for four proteins in D2O solution. Of these, myoglobin (MYO) has a very high fraction of a-helix, immunoglobulin (IMU) has substantial /1-sheet component, lactoferrin (LAF) has both a and j3 contributions, and a-casein (CAS) supposedly has no extended structure. The FTIR spectra of these proteins change little, the primary difference...

Polymorphism has been identified in the KL-(BEDT-TTF)2Cu(CF3)4(DBCE) system [44]. The primary difference between the kl- and KL -phases is that adjacent BEDT-TTF layers in the KL-phase are tilted in opposite directions, while those in the KL-phase are tilted in the same direction. Also similar to the KL-phases, the trifluoromethyl groups in the kl -phase are disordered. These two phases have similar morphologies and EPR line widths [45] and are thus difficult to distinguish from each other. It is currently not known how prevalent the KL -phase is, although it appears to have similar physical properties to the KL-phase. 

To illustrate an application of nonlinear quantum dynamics, we now consider real-time control of quantum dynamical systems. Feedback control is essential for the operation of complex engineered systems, such as aircraft and industrial plants. As active manipulation and engineering of quantum systems becomes routine, quantum feedback control is expected to play a key role in applications such as precision measurement and quantum information processing. The primary difference between the quantum and classical situations, aside from dynamical differences, is the active nature of quantum measurements. As an example, in classical theory the more information one extracts from a system, the better one is potentially able to control it, but, due to backaction, this no longer holds true quantum mechanically. 

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