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New System

More than 200 distinct topological methods of multipolymer organization are already known and new topologies are being reported frequently. In addition to the usual molecular specifications, the time sequence of synthesis is important in many cases and needs to be preserved in the nomenclature for a full comprehension of the final product. [Pg.32]

The following nomenclature scheme uses a short list of elements (Table 3.1), polymers and polymer-reaction products, which are reacted together in [Pg.32]

This nomenclature primarily answers three questions about the chemical entity (1) which polymers are combined, (2) principal modes of combination, and (3) the time sequence of reaction. Other items of information, such as weight proportions, molecular weights, morphology, tacticity, etc. can be included as ancillary items but will not be discussed in detail below. [Pg.33]

While the nomenclature scheme was originally derived to describe polymer blends, blocks, grafts, and IPNs, generalizing the scheme to include random and alternating copolymers and starblock copolymers made the [Pg.33]

As with other nomenclature schemes, the objective will be to name the most important product(s) of a reaction. In some cases, several isomers are possible, but listing each one all the time becomes cumbersome and perhaps misleading. [Pg.34]


CALCULATE TEMPERATURE-INDEPENOENT PARAMETERS ONLY FOR NEW SYSTEM... [Pg.304]

IF ESTIMATES ARE AVAILABLE FOR A,X,Y,(ANO T) THEY CAN BE ENTERED IN THESE VARIABLES - OTHERWISE THESE VARIABLES SHOULD BE SET TO ZERO. KEY SHOULD BE 1 ON INITIAL CALL FOR A NEW SYSTEM AND 2 OTHERWISE. [Pg.322]

FOR NEW SYSTEMS WITHOUT IR. IE SPECIFIED. FIND IR. IE AS LEAST SOLUBLE... [Pg.336]

Key = 1 represents an initial calculation for a new system Key 2-5 are subsequent calculations not differing significantly in time requirements Key = 6,7 require temperature derivatives of virial coefficients. [Pg.353]

A new system from Agfa Gaevert which is under development for special NDT-... [Pg.469]

To operate the MPI or LPI equipment at stable and reprodncable inspection conditions modern units are equipped with a monitoring and control system called "Quality Assurance Package" (termed QAP). The QAP System is ba.sed on an industrial PC with a bus system and field sensors. It ensures that process parameters important for the reproducability of the MPI or LPI are controlled an held between defined limits by a central computer system. It can be adapted to any old system, as well as integrated into new systems. [Pg.628]

The characteristic isotherm concept was elaborated by de Boer and coworkers [90]. By accepting a reference from a BET fit to a standard system and assuming a density for the adsorbed film, one may convert n/rim to film thickness t. The characteristic isotherm for a given adsorbate may then be plotted as t versus P/P. For any new system, one reads t from the standard r-curve and n from the new isotherm, for various P/P values. De Boer and co-work-ers t values are given in Table XVII-4. A plot of t versus n should be linear if the experimental isotherm has the same shape as the reference characteristic isotherm, and the slope gives E ... [Pg.633]

On investigating a new system, cyclic voltannnetty is often the teclmique of choice, since a number of qualitative experiments can be carried out in a short space of time to gain a feelmg for the processes involved. It essentially pennits an electrochemical spectrum, indicating potentials at which processes occur. In particular, it is a powerfid method for the investigation of coupled chemical reactions in the initial identification of mechanisms and of intemiediates fomied. Theoretical treatment for the application of this teclmique extends to many types of coupled mechanisms. [Pg.1929]

Calculating points on a set of PES, and fitting analytic functions to them is a time-consuming process, and must be done for each new system of interest. It is also an impossible task if more than a few (typically 4) degrees of freedom are involved, simply as a consequence of the exponential growth in number of ab initio data points needed to cover the coordinate space. [Pg.254]

The reason a single equation = ( can describe all real or hypothetical mechanical systems is that the Hamiltonian operator H takes a different form for each new system. There is a limitation that accompanies the generality of the Hamiltonian and the Schroedinger equation We cannot find the exact location of any election, even in simple systems like the hydrogen atom. We must be satisfied with a probability distribution for the electron s whereabouts, governed by a function (1/ called the wave function. [Pg.169]

As ehemists, mueh of our intuition eoneeming ehemieal bonds is built on simple models introdueed in undergraduate ehemistry eourses. The detailed examination of the H2 moleeule via the valenee bond and moleeular orbital approaehes forms the basis of our thinking about bonding when eonfronted with new systems. Let us examine this model system in further detail to explore the eleetronie states that arise by oeeupying two orbitals (derived from the two Is orbitals on the two hydrogen atoms) with two eleetrons. [Pg.295]

Shortly after publication of Dalton s New System of Chemical Philosophy Gay-Tussac announced his observations that volumes of gas which combine with each other and the volume of the combination thus formed are in direct proportion to the sum of the volumes of the constituent gases. The volumetric proportions of Gay-Tussac and Dalton s gravimetric ratios indeed supplement each other, although they themselves contested and rejected each other s concepts. [Pg.29]

For two thousand years atoms were considered the smallest and indivisible units of nature. At the beginning of the nineteenth century Dalton got chemistry on the path of atomic theory with his book, A New System of Chemical Philosophy, in which he argued that unbreakable atoms form compounds by linking with other atoms in simple... [Pg.32]

Resonance, polarity, and steric considerations are all believed to play an important role in copolymerization chemistry, just as in other areas of organic chemistry. Things are obviously simphfied if only one of these is considered but it must be remembered that doing this necessarily reveals only one facet of the problem. Nevertheless, there are times, particularly before launching an experimental investigation of a new system, when some guidelines are very useful. The following example illustrates this point. [Pg.443]

An approach to copolymerization has been advanced by Price and Alfrey which attempts to both combine resonance and polarity considerations and accomplish the data reduction strategy of the last paragraph. It should be conceded at the outset that the Price-Alfrey method is only semiquantitative in its success. Its greatest usefulness is probably in providing some orientation to a new system before launching an experimental investigation. [Pg.444]

Experimental Mass Transfer Coefficients. Hundreds of papers have been pubHshed reporting mass transfer coefficients in packed columns. For some simple systems which have been studied quite extensively, mass transfer data may be obtained directiy from the Hterature (6). The situation with respect to the prediction of mass transfer coefficients for new systems is stiU poor. Despite the wealth of experimental and theoretical studies, no comprehensive theory has been developed, and most generalizations are based on empirical or semiempitical equations. [Pg.36]

Composites. The history of phenoHc resin composites goes back to the early development of phenoHc materials, when wood flour, minerals, and colorants were combined with phenoHc resins to produce mol ding compounds. In later appHcations, resin varnishes were developed for kraft paper and textile fabrics to make decorative and industrial laminates. Although phenoHcs have been well characterized in glass-reinforced composites, new developments continue in this area, such as new systems for Hquid-injection molding (LIM) and sheet-molding compounds (SMC). More compHcated composite systems are based on aramid and graphite fibers. [Pg.307]

In 1954, the 10th CGPM added the degree Kelvin as the unit of temperature and the candela as the unit of luminous intensity. At the time of the 11th CGPM in 1960, this new system with six base units was formalized with the tide International System of Units. Its abbreviation in all languages is SI, from the French l e Sjstume International d Unitus. [Pg.307]

In general, the test object caimot be heated above its operating temperature in space. As free molecular conditions are obtained around the object, it outgases and, if solar-spectmm photons impinge on the object, increases the release of gas. Because the object is in a vessel and the area of the hole lea ding to the gas pump is small compared with the projected interior area of the vessel, molecules originating from the test object can return to the test object provided that they do not interact in some manner with the vessel walls and the other components of the molecular environment. The object inside the vessel estabhshes an entirely different system than the clean, dry, and empty vacuum vessel. The new system no longer has the capabiUty to reach the clean, dry, and empty base pressure within a reasonable time. [Pg.368]

General synthetic methods were developed after 1920 and extended to many new systems. Oxidative syntheses of dyes are primarily of historical interest (1), whereas nonoxidative syntheses are the most versatile and employ varied combinations of nucleophilic and electrophilic regents. One review Hsts references for the synthesis of dyes prepared before 1959 (12), and another review provides supplemental references to more recent compounds (13). Many nucleophilic and electrophilic reagents used to synthesize cyanine and related dyes are tabulated in Reference 16. [Pg.394]

Consider the possibility of scahng up the design of a new system from experimental data obtained in a laboratory-bench scale or a small pilot-plant unit. [Pg.1363]

Consider the possibility of developing for the new system a rigorous, theoretically based design procedure which will be valid over a wide range of design conditions. [Pg.1363]


See other pages where New System is mentioned: [Pg.222]    [Pg.290]    [Pg.296]    [Pg.300]    [Pg.311]    [Pg.319]    [Pg.326]    [Pg.327]    [Pg.330]    [Pg.331]    [Pg.336]    [Pg.225]    [Pg.347]    [Pg.472]    [Pg.789]    [Pg.11]    [Pg.455]    [Pg.446]    [Pg.40]    [Pg.199]    [Pg.212]    [Pg.86]    [Pg.234]    [Pg.21]    [Pg.197]    [Pg.1481]    [Pg.1972]    [Pg.1985]    [Pg.2142]   


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