Principal deficiency

Biodegradation studies of starch blends have not been conclusive where a nondegradable synthetic polymer has been the blend component probably biodisiategration would be a better term to describe these polymers. The principal deficiencies of products based on this chemistry, aside from the incomplete biodegradation, are water-sensitivity of manufactured articles, and the balance of this and biodegradation with the starch level ia the product. 

Calcium Chelates (Salicylates). Several successhil dental cements which use the formation of a calcium chelate system (96) were developed based on the reaction of calcium hydroxide [1305-62-0] and various phenohc esters of sahcyhc acid [69-72-7]. The calcium sahcylate [824-35-1] system offers certain advantages over the more widely used zinc oxide—eugenol system. These products are completely bland, antibacterial (97), facihtate the formation of reparative dentin, and do not retard the free-radical polymerization reaction of acryhc monomer systems. The principal deficiencies of this type of cement are its relatively high solubihty, relatively low strength, and low modulus. Less soluble and higher strength calcium-based cements based on dimer and trimer acid have been reported (82). 

The principal deficiency of CISD is the lack of the TI term, which is the main reason for CISD not being size extensive. Furthermore, this term becomes more and more important as the number of electrons increases, and CISD therefore recovers a smaller and smaller percentage of the correlation energy as the system increases. There are various approximate corrections for this lack of size extensivity which can be added to standard CISD. The most widely known of these is the Davidson correction, sometimes denoted CISD - - Q(Davidson), where the quadruples contribution is approximated as... 

The principal deficiency of source-based nomenclature is that the chemical structure of the monomeric unit in a polymer is not identical with that of the monomer, e.g., -CHX-CH2- versus CHX=CH2. The structure of the constitutional repeating unit (CRU) may also not be clearly identified in this scheme for example, the name polyacrylaldehyde does not indicate whether (i) the vinyl group or (ii) the aldehyde group was the locus of polymerization. 

All excluded volume theories for branched chains suffer, however, from a principal deficiency since the assumption is tacitly made that all monomeric units in the molecule may have, in principle, the chance to interact with each other. This is, however, a too extensive assumption since for sterical reasons two remote segments can never form a contact. Hence, the excluded volume effect is highly overestimated for densely branched chains. In fact, highly branched polymers show the phenomenon of swelling but no detectable distortion of Gaussian chain behavior117,137,138,179. ... 

Because of its vital character to life as we know it, photosynthesis has been investigated intensively and the general features of the process are now rather well understood. The principal deficiencies in our knowledge include just how the light absorbed by the plants is converted to chemical energy and the details of how the many complex enzyme-induced reactions involved take place. 

A critique and more thorough review of the time-lag ideas has been published [7]. The principal value of time-lag concepts lies in the wide range of problems to which they can be applied with relative ease. Their principal deficiency lies in the difficulty of relating Xi to the fundamental processes occurring. If the one-dimensional, time-dependent conservation equations are linearized about any one of the steady-state solutions of Chapter 7 and p is calculated from a perturbation analysis, then it is found... 

The principal deficiency of CISD is the lack of the T term, which is the main reason for CliJD not being size extensive. Furthermore, this term becomes more and more... 

Sokolowski and Steele have adapted the spherical harmonic expansion technique described in Section III.A to the calculation of the density profiles of nonspherical molecules in contact with solid surfaces. They have used the results to investigate molecular orientation effects in high temperature adsorption from the gas phase. The RAM theory described in Section III.E has been extended to the adsorption of fluids on solid surfaces by Smith et al. ° for hard-sphere interactions and by Sokolowski and Steele to the case of more realistic fluid-solid interactions. The principal deficiency of the approach is the accuracy of the predicted correlation functions for the bulk fluid which are required as input to the theory. 

One of the principal deficiencies of the older cephalosporins was the lack of resistance to P-lactamases. Compounds with improved (3-lactamase resistance have one or more of the following characteristics a second, monovalent substituent on the CC-carbon of the C-7 acyl group such as found in cefamandole (30) and cefoperazone (34) a syn-oxime substituent, eg, cefuroxime (35) and ceftriaxone (39) a methoxy, or formamido, substituent on the (3-lactam ring at the 7cc-position such as in cefoxitin (23). However, these various substituents have different effects, and increased resistance to one enzyme does not indicate resistance to all P-lactamases. The 7cc-methoxy, or formamido, group is the most effective in imparting a broad spectmm of resistance to P-lactamases, followed by acyl side-chain oxime ether substituents. Thus cefuroxime (35), the first oximino—cephalosporin, has a P-lactamase resistance spectmm similar to that of cefotaxime (36) whereas the less resistant cefamandole (30) is similar to cefoperazone (34). 

In European RMBS transactions, bonds are not generally written down when losses are incurred in the collateral pool. Instead, the losses are recorded in a principal deficiency ledger, which records the extent to which the balance outstanding on the notes exceeds the remaining assets. Usually, both excess spread and the reserve fund can be used to cover losses and so pay down the principal deficiency ledger. This mechanism is beneficial to holders of the lower-rated notes because the notes do not get written off immediately and any future excess spread will be used to cover the loss. 

An asset performance trigger event would occur if a principal deficiency is recorded in the Class A Principal Deficiency Ledger. This means that the total balance of realised losses that have not been covered by either the reserve fund or with excess spread exceed the aggregate outstanding amount of the subordinate notes. If this occurs, all receipts on the mortgages will be allocated to the issuers and the seller on a pro rata basis. The notes will start to redeem early with all the Class A notes being redeemed on a pro rata basis. When all the Class A notes have been redeemed in full, the Class B notes would be redeemed, and so on for all other classes of notes until all the notes are redeemed or the trust no longer has any assets. 

A principal deficiency being recorded on the Class C or Class B principal deficiency ledger. 

The reserve fund being used to cover a principal deficiency and not being replenished. 

Excess spread is available to build up the reserve fund to its required level and cover any principal deficiencies. For example, in the Holmes Financing transactions there is a mechanism whereby, if the yield on the mortgages falls below a certain specified level, excess spread will be trapped in a second reserve fund to provide additional credit enhancement as compensation for the reduction in excess spread. 

A principal deficiency of the OBE model is the fact that it has to introduce a scalar-isoscalar a-boson in the mass range 500-700 MeV, the existence of which is not supported by any experimental evidence. Furthermore, the model is restricted to single exchanges of bosons that are laddered in an unitarizing equation. Thus, irreducible multi-meson exchanges, which may be quite sizable (see below), are neglected. 

Forced flow separations overcome the principal deficiencies of capillary flow separations by establishing a constant and optimum mobile phase velocity. Forced flow separations require specially designed developing chambers exploiting either centrifugal or pneumatic forces to drive the mobile phase through the layer. Centrifugal methods are more popular for preparative-scale separations and have been little used for analysis. The preferred approach for analytical separations is to seal the open face of the layer by contact with a flexible membrane, under hydraulic pressure, and deliver the mobile phase to... 

A slightly more sophisticated method is the so-called minimum-image (MI) convention, in which all interactions between the central particle and its nearest image of all other particles are included. This is a significant improvement over a SC, since the central particle and its interacting particles constitute an electroneutral entity. The MI convention has frequently been appUed to simulate simple electrolytes and, to some extent, weakly asymmetric electrolytes. However, it suffers from the same principal deficiencies as a SC, and the MI convention becomes insufficient for higWy asymmetric electrolytes. 

And at last, the third and the most fundamental factor is the ehange of nanocomposite structure at the introduction of particulate filler in high-elastieity polymeric matrix. As Balankin showed [9], classical theory of entropic high-elastieity has a number of principal deficiencies due to non-fulfilment for real rubbers of two main postulates of this theory, namely, essentially non-Gaussian statisties of real polymeric networks and lack of coordination of postulates about Gaussian statistics and incompressibility of elastic materials. Last postulate means, that Poisson s ratio v of these materials must be equal to 0.5. As it is known [10], Gaussian statistics of macromolecular coil is correct only in case of its dimension Dj=2.0, i.e., for coil in 0-solvent. Since between value Df and fractal dimension... 

By feeding a diet composed of 16% casein, approximately 4% salts and vitamins and the remainder sucrose. Burr and Burr were able to induce a dietary deficiency syndrome which they later traced to the absence of linoleic acid. The principal deficiency symptoms were a diminished growth rate and a scaly dermatitis seen principally on the feet and tail. An example of a fat deficient rat is shown in Figure 1. Most of the organs of the body are affected by the deficiency and aberrations in structure or function of many tissues have been observed. Reproduction is impaired, the liver becomes fatty., kidney function is impaired, the electrocardiogram is abnormal, and the permeability of the skin toward water is much increased- This leads to evaporative loss of water and of heat from the body accounting for an increased food consumption and a diminished caloric efficiency. 

There have been a few full-scale applications of PIC to protect reinforcing steel against corrosion, and it must still be considered largely an experimental process. Some of the disadvantages of PIC are that the monomers are expensive and the processing is lengthy and costly. The principal deficiency identified to date has been the tendency of the concrete to crack during heat treatment. ... 

---