Existing structures

The abbreviation QSAR stands for quantitative structure-activity relationships. QSPR means quantitative structure-property relationships. As the properties of an organic compound usually cannot be predicted directly from its molecular structure, an indirect approach Is used to overcome this problem. In the first step numerical descriptors encoding information about the molecular structure are calculated for a set of compounds. Secondly, statistical methods and artificial neural network models are used to predict the property or activity of interest, based on these descriptors or a suitable subset. A typical QSAR/QSPR study comprises the following steps structure entry or start from an existing structure database), descriptor calculation, descriptor selection, model building, model validation. 

Adding nucleotides to the 3 oxygen of an existing structure is called elongation and leads ultimately to a polynucleotide The most important polynucleotides are ribonu cleic acid (RNA) and deoxyribonucleic acid (DNA) As we shall see m later sections the polynucleotide chains of DNA and some RNAs are quite long and contain hundreds of thousands of bases... 

Demolition and alteration to existing structure Surplus equipment, supplies and materials, royalty payments Design modifications, construction modifications, and extra work during startup... 

Sometimes there is no practical, economical way to reduce deposition, protect surfaces cathodically, change design and operation, or treat existing systems chemically. A material change is required. The most economical solution usually is to coat existing structures with water-impermeable, sacrificial, or corrosion-resistant materials. 

Existing structures (their condition, type of construction, etc.) ... 

Crevices should be avoided. They allow moisture and dirt to collect with a resultant increase in corrosion. If crevices either cannot be avoided, or are present on an existing structure, they can often be filled by welding or by using a filler or mastic. 

Estimate of current required The surface area of the structure is calculated and the current density required for the particular environment is selected (Table 10.26). In the case of an existing structure the condition of the coating may be unknown and the application of a temporary cathodic-protection system may be necessary to determine the amount of current required for protection, as established by the potential. Such a test to determine the... 

In the industrial world of manufacturing plants, power stations and the like, more than 80% of painting is concerned with the maintenance of existing structures and plant. Although airless spraying can be more than 20 times faster than brush application and conventional spray some four times as fast, there are many occasions where access difficulties and safety considerations prevent their use. Rollers and brushes therefore continue to be widely used. 

The diversity of these subcellular actin structures is remarkable and appears to be determined by the interactions of many actin-binding proteins (ABPs) as well as by changes in the concentrations of intracellular signaling molecules such as Ca and cAMP, by small GTP-binding proteins, and by signals arising from mechanical stress. Approximately 50% of the actin molecules in most animal cells are unpolymerized subunits in the cytosolic pool and exist in a state of dynamic equilibrium with labile F-actin filamentous structures (i.e., new structures are formed while existing structures are renewed) (Hall, 1994). 

Fortunately, derivatization for f.a.b.-m.s. makes no special demands on the carbohydrate chemist. The best derivatives are those that have been used for a very long time in carbohydrate work, namely, the per-O-acetyl and the per-O-methyl. Thus, f.a.b.-m.s. can be readily accommodated into existing structural programs. 

Myriad FRP products are available for either the repair or the outright replacement of existing structures. In addition to chemical-process pipes and tanks, FRP composite products include structural shapes, bridge systems, grating, handrail ladders, etc. 

Two or more substances that have the same molecular formula but different structures and properties are called isomers. Two main types of isomers exist. Structural isomers are ones in which the atoms are bonded in different orders. In stereoisomers, all the bonds in the molecule are the same, but the spatial arrangements are different. 

One-dimensional structures do not exist. Structures are always three-dimensional. The term one-dimensional is acceptable to express specifically named, highly anisotropic properties, such as one-dimensionalconductivity , one-dimensionalconnection or onedimensional disorder . The dimensionality of a structure is a meaningless phrase. 

Another difficulty is that a peptide may be able to bind to an existing neutralizing monoclonal antibody by an induced-fit mechanism that is somehow driven by the pre-existing structure of the antibody paratope. However, the same induced-fit process may not take place when the peptide is used as the immunogen and is confronted in the host by a large population of B cell receptors allowing a variety of other interactions. 

Ericson, S.-0. and H. Schmied, Modified Technology in New Constructions and Cost-Effective Remedial Action in Existing Structures to Prevent Infiltration of Soil Gas Carrying Radon. In Proceedings of the 3rd International Conference on Indoor Air Quality and Climate, Stockholm, 5 153-158 (1984). 

The hydrogen producing potential of pyrolysis can be illustrated by the following overall reactions. Here, an average typical elemental composition is assumed (not corresponding to an existing structure) ... 

In addition to the indications of an octahedral trans effect presented, there exists structural information in the form of bond lengths and spectral data similar to that described earlier for square planar complexes. Although the trans effect in octahedral complexes is not the dominant influence that it is in square planar complexes, there is no doubt that there is such an effect. 

Clarification of existing structure-induction-metabolism relations... 

Extensive structure-activity relationships for NO release from oximes do not currently exist. Structural changes do influence the rate of NO release from the nitro-containing oximes, such as FK409 (9, ti/2 = 46 min, Fig. 7.2) [46, 59]. Changing the alkyl group attached to the carbon of the nitro group can increase (12, -CH2OCH3, ti/2 = 2.6 min, Fig. 7.2) or decrease (13, -tertBu, ti/2 = 2900 min, Fig. 7.2) the rate of NO release from... 

When options for reinforcing an existing structure are not feasible, an independent concrete shell (or cocoon) can be built around the structure, Factors which make shells an attractive option include ... 

Retrofitting existing structure is discussed in Structural Design for Physical Security Slate of the Practice Report (ASCE Physical Security). Although the blast load is specifically related to external or internal bomb threats, the analysis technique and design approaches for hardening structures are similar in many ways. 

It is often desirable to utilize the in-plane capacity of precast panels to function as shear walls in resisting lateral loads. The connections typically provided between adjacent precast members are often inadequate to develop the required in-planc capacity. It is normally very expensive to add this capacity to an existing structure. 

Headed studs are normally used to secure a roof slab to a structural steel framing system for rebound loads in new designs. This option may not available for upgrading existing structures. It may be necessary to provide through bolts to the structural frame with a backing plate on the top side of the stab. 

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