Repeats, exact

The whole process is then repeated exactly as described above. The absorption tubes are then weighed and attached to the apparatus ffull details will be given below when a complete combustion is described), and the above process repeated. The absorption tubes are detached and reweighed. They should not have gained in weight by more than o i... 

There are two issues that are relevant here. First, the adsorbates in a supercell calculation necessarily have a long-range pattern that is repeated exactly as the supercell is repeated. With periodic boundary conditions, it is impossible to model any kind of truly random arrangement of adsorbates. The good news is that in nature, it happens that adsorbates on crystal surfaces often do exhibit long-range ordering, especially at low temperatures, so it is possible for calculations to imitate real systems in many cases. 

In this publication, besides repeating exactly arguments presented earlier in the 1911 article published by his Theosophist co-religionist, which he carefully cites, Noircarme presents us with a mathematical table containing all the constituent elements of an n-dimensional solid. Of particular interest to this student of esoteric geometries was the development of the binomial... 

There is a tendency among control and statistics theorists to refer to trial and error as one-variable-at-a-time (OVAT). The results are often treated as if only one variable were controlled at a time. The usual trial, however, involves variation in more than one controlled variable and almost always includes uncontrolled variations. The trial-and-error method is fortunately seldom a random process. The starting cycle is usually based on manufacturers specifications or experience with a similar process and/or material. Trial variations on the starting cycle are then made, sequentially or in parallel, until an acceptable cycle is found or until funds and/or time run out. The best cycle found, in terms of one or a combination of product qualities, is then selected. Because no process can be repeated exactly in all cases, good cure cycles include some flexibility, called a process window, based on equipment limitations and/or experience. 

By far the most important requirement of a publication is reproducibility of the method reported. It is not sufficient to have carried out the process only once if it is expected that other investigators will want to repeat it. There are always factors that influence the process that may be overlooked at first, and which can have a major effect on the purification procedure if varied slightly. The reported process should always be repeated exactly as described before submitting the manuscript for publication. 

The structure of isotactic polystyrene has been studied by means of x-ray diffraction [Natta and Corradini (152,153)]. It is found that the chain configuration is helical, with three monomer units per repeat exactly as in polypropylene. The only difference is that the chain repeat of 6.65 A in polystyrene implies an opening of the CCC bond angles in the chain to 116.5°. The orientation of the benzene ring is apparently not settled. In the above structure, if the axis of the benzene ring were perpendicular to the helix axis, then the plane of the benzene ring would be almost exactly perpendicular to the helix axis. In a variation of this structure proposed on the basis of stereochemical considerations [Bunn and Howells (30)], and shown in Fig. 16, the plane of the benzene ring... 

Present-day structures of proteins provide some hints on the role of gene duplications in evolution. Proteins commonly occur in families. These are structurally related enzymes catalyzing reactions of the same class with different substrate specificities. Examples are families of proteases or dehydrogenases. In addition to this, one observes interesting regularities in the structures of many globular proteins Substructures (so-called motifs) are often repeated exactly or with minor modifications only. Such repetitions were found in the same protein molecule as well as in different protein molecules. Both the modular structure of polymers as well as the existence of protein families can be explained by a gene duplication mechanism. 

The inside address contains the name of the person to whom you are writing, the person s title or position, the name of the company or organization, the full address (street or post office box, city, state, ZIP Code). The first line of the inside address should appear at least two spaces below the last line of the heading. (The inside address information should be repeated exactly on your letter s envelope.)... 

After an initial transient, the solution settles into an irregular oscillation that persists as t —> °°, but never repeats exactly. The motion is aperiodic. 

Whenever complete chemical analyses are provided for soil extracts or irrigation waters, the sum of major cations (mmol(+) L-1) should approximately equal the sum of all major anions (mmol(—) L-1). Repeated exact agreement, however, indicates that one ion is being determined by difference. This is usually sulfate for recent analyses, or sodium for older analyses. Also, reported concentrations of carbonate should be negligible at solution pH >9. In the water-supply literature, Ca plus Mg concentrations are reported as hardness, the chemically equivalent quantity of CaC03 in milligrams per liter. Concentrations of bicarbonate plus carbonate may be reported -as alkalinity, the equivalent acid-neutralizing capacity of the water. 

The area under the load xtension curve is the area of work to extend the fiber. The load extension curve of a fiber can be repeated exactly if the fiber is not extended beyond 30% extension, and if it is allowed to recover for 4 h without tension in water at room temperature (see Section 5.4.1). This means that the work to extend a wool fiber up to 30% ( the 30% index ) under different conditions can be compared. Similarly, the work to extend a wool fiber after some chemical treatment can be compared with the work to extend the untreated fiber after it has been allowed to relax without tension for 24 h after the first, calibrating, load-extension experiment. 

Traditionally, systems of measurement have employed units that related to various parts or proportions of the human body. Ready and convenient measuring tools in earlier times included the hand, the foot, the thumb, and the pace. Because these human measures tend to vary somewhat from person to person, no work that depended on measurements could be repeated exactly, even if the same person carried it out. Specialization in tasks eventually led to... 

When working with an unknown material, double check your results by running the sample at least twice to ensure that your results are repeatable. Exactly what else might occur depends heavily on the material being tested. 

We may repeat exactly the same lenghty calculations starting with (12.5.5) and the expansion... 

In the case of proton transfer in the carboxylic acid-nitrogen base complexes, the proton is transferred from the acid to a base in order to produce a more stable pair. Similarly as in solution, the occurrence of proton transfer is determined by the relative acidities and basicities of the donor and acceptor. However, the solution acid-base behavior is not repeated exactly in the solid state. On the one hand, the charge separation that results from the proton transfer is less favorable in the solid state than in the solution, as there is no additional stabilization of... 

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