Novel Approaches

A novel approach for suppression of grain noise in ultrasonic signals, based on noncoherent detector statistics and signal entropy, is presented. The performance of the technique is demonstrated using ultrasonic B-scans from samples with coarse material structure. 

Experimental results on real ultrasonic B-scan data, acquired from samples with coarse material structure, are presented to demonstrate the power of the novel approach. 

The presence of surface conductance behind the slip plane alters the relationships between the various electrokinetic phenomena [83, 84] further complications arise in solvent mixtures [85]. Surface conductance can have a profound effect on the streaming current and electrophoretic mobility of polymer latices [86, 87]. In order to obtain an accurate interpretation of the electrostatic properties of a suspension, one must perform more than one type of electrokinetic experiment. One novel approach is to measure electrophoretic mobility and dielectric spectroscopy in a single instrument [88]. 

Crippen G M 1977 A novel approach to calculation of conformation distance geometry J. Comput. Rhys. 24 96-107... 

J S, I Morize, P R Menard, D L Cheney, C Hulme and R F Labaudiniere 1999. New 4-Point irmacophore Method for Molecular Similarity and Diversity Applications Overview of the thod and Applications, Including a Novel Approach to the Design of Combinatorial iraries Containing Privileged Substructures. Journal of Medicinal Chemistry 42 3251-3264. 

Polymerization ofiVIasked Disilenes. A novel approach, namely, the anionic polymerization of masked disilenes, has been used to synthesize a number of poly(dialkylsilanes) as well as the first dialkylamino substituted polysilanes (eq. 13) (111,112). The route is capable of providing monodisperse polymers with relatively high molecular weight M = lO" — 10 ), and holds promise of being a good method for the synthesis of alternating and block copolymers. 

A novel approach to the modification of aminoglycoside pharmacokinetics is under investigation (84). Administration of gentamicin encapsulated in egg phosphatidylcholine Hposomes has been found to lead to a longer half-life and much higher spleen and Hver levels for the gentamicin component. This formulation is undergoing clinical study (85). 

A novel approach to the problem of amiaoglycoside nephrotoxicity has been to search for compounds that can inhibit toxicity without compromising efficacy. A number of agents have been reported to reduce amiaoglycoside toxicity ia animal models the most extensively studied of these is sodium polyaspartate (103—107). 

Chemical recovery ia sodium-based sulfite pulpiag is more complicated, and a large number of processes have been proposed. The most common process iavolves liquor iaciaeration under reduciag conditions to give a smelt, which is dissolved to produce a kraft-type green liquor. Sulfide is stripped from the liquor as H2S after the pH is lowered by CO2. The H2S is oxidized to sulfur ia a separate stream by reaction with SO2, and the sulfur is subsequendy burned to reform SO2. Alternatively, ia a pyrolysis process such as SCA-Bidemd, the H2S gas is burned direcdy to SO2. A rather novel approach is the Sonoco process, ia which alumina is added to the spent liquors which are then burned ia a kiln to form sodium aluminate. In anther method, used particulady ia neutral sulfite semichemical processes, fluidized-bed combustion is employed to give a mixture of sodium carbonate and sodium sulfate, which can be sold to kraft mills as makeup chemical. 

In a novel approach, enantiomerically enriched (R)-pantolactone (9) is obtained in a enzymatic two-step process starting from racemic pantolactone. 

In a novel approach to vitamin K, Hoffmann-La Roche has exploited the potential acidity at C-3 as a means to attach the side chain of vitamin (36). Menadione was reacted with cyclopentadiene to yield the Diels-Alder adduct. The adduct is treated with base and alkylated at C-3 with phytyl chloride. A retro Diels-Alder reaction yields vitamin K. Process improvements in this basic methodology have been claimed by Japanese workers (37). 

M. M. Cook and co-workers, "Sodium Borohydride Reductions—Novel Approaches to Decolorization and Metals Removal iu Dye Manufacturiug and Textile Effluent Applications," 203rd National Meeting of the American Chemical Society, San Erancisco, Apr. 5—10,1992. 

Such reductive ring contractions of sulfones are formally similar to two other methods capable of supplanting a sulfur atom by a carbon-carbon double bond the Ramberg-Backlundand Stevens rearrangements. The distinguishing feature of this novel approach to cyclobutenes consists in the resultant higher level of alkyl substitution at the sp -hybridized centers. 

Macrocyclic polyethers containing the 2.2-paracyclophane unit are interesting structures and several such compounds have been prepared . Despite the diverse structural possibilities, the syntheses of these molecules have generally been accomplished by straightforward Williamson ether syntheses. The only unusual aspect of the syntheses appears to be a novel approach to certain paracyclophanes developed by Helgeson (see footnote 7a in Ref. 91). The first step of Eq. (3.28) illustrates the formation of the required tetrol, which is then treated with base (KOH or KO-t-Bu) and the appropriate diol dito-sylate to afford the macrocycle. 

Although the preparation of the quite complex selector modules prior to the synthesis of the library represented a rather significant synthetic effort, this study showed clearly the potential of combinatorial chemistry in the early development stage of a chiral separation medium and demonstrated a novel approach to rapid screening that might be amenable to full automation in the future. 

In a second novel approach, Mullen and co-workers further developed an inter-molecular repetitive Diels-Aldcr procedure for the generation of dendritic and hy-perbranched poly(phenylcnc)s. Hereby, they applied the concept of reacting A2B-type monomers, in this case monomers containing both cyclopcnladienone (dien-... 

A novel approach to azabicyclic ring systems, based on an epoxide-initiated electrophilic cyclization of an alkyl azide, has been developed by Baskaran. A new stereo- and enantioselective synthesis of the 5-hydroxymethyl azabicyclic framework 91a, present in (+)- and (-)-indolizidines 167B and 209D, for example, was... 

L. Seglin We have heard today two rather novel approaches to methanation the steam-moderated RMProcess and the slurry methanation process. These are the results of new or recent R D. What can we visualize beyond that Would it be some other exotic process ... 

Currently, the majority of all approved diugs for treating insomnia interact with the GABAa receptor system. The major focus of the rest of this overview will therefore be on these types of dtugs and the introduction of two novel approaches, either recently approved or in late stage development. 

Several novel approaches to the treatment of insomnia have attracted much attention among researchers. 

A novel approach to RAFT emulsion polymerization has recently been reported.461529 In a first step, a water-soluble monomer (AA) was polymerized in the aqueous phase to a low degree of polymerization to form a macro RAFT agent. A hydrophobic monomer (BA) was then added under controlled feed to give amphiphilic oligomers that form micelles. These constitute a RAFT-containing seed. Continued controlled feed of hydrophobic monomer may be used to continue the emulsion polymerization. The process appears directly analogous to the self-stabilizing lattices approach previously used in macromonomer RAFT polymerization (Section 9.5.2). Both processes allow emulsion polymerization without added surfactant. 

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