Cotton independence

In the USSR the Aral region provided 90% of cotton and 40% of rice. The country became cotton-independent. This was achieved, primarily, through extensive irrigated farming ignoring herewith the likely consequences of such agricultural practices. 

In a study of the adsorption of soap and several synthetic surfactants on a variety of textile fibers, it was found that cotton and nylon adsorbed less surfactant than wool under comparable conditions (59). Among the various surfactants, the cationic types were adsorbed to the greatest extent, whereas nonionic types were adsorbed least. The adsorption of nonionic surfactants decreased with increasing length of the polyoxyethylene chain. When soaps were adsorbed, the fatty acid and the aLkaU behaved more or less independently just as they did when adsorbed on carbon. The adsorption of sodium oleate by cotton has been shown independently to result in the deposition of acid soap (a composition intermediate between the free fatty acid and the sodium salt), if no heavy-metal ions are present in the system (60). In hard water, the adsorbate has large proportions of lime soap. 

But not all the potash, kelp, and barilla in Europe and North America could keep up with the cotton textile factories of Britain and France. France was in a particularly dire situation. Even under normal conditions, her natural sources of alkali were insufficient. Then France supported the American War of Independence, and British ships cut off the French supply of American potash. With gunpowder and textile industries dependent on potash, France had to find a way to make artificial alkali. 

A comparison of the thus calculated with the measured specific rotations of the 0th- to 4th-generation dendrimers of this kind gave a close resemblance, with a curve, approaching asymptotically a limiting value (Fig. 26). It was also shown that the shape of this curve was independent of solvent, concentration and temperature. This was not the case when CD spectra of these dendrimers were compared (Fig. 27) in solvents such as CH2C12 and f-butyl methyl ether a constant rise of the Cotton effect was observed, which correlates with the increasing amount of benzene chromophores in the dendrimers. However, in the... 

A few examples may serve to illustrate the implications of relative crystallinity and especially of intercrystalline reactivity. Two independent investigations27 29 have shown that cotton fibers are reduced to a... 

Cotton dust activates complement vitro by both the classical (antibody dependent) and alternative (antibody independent) pathways (12,47,48). It is proposed that endotoxins may be the agents responsible for complement activation (49). Cotton dust extractions maximizing endotoxin content are 10 times more potent than other extracts in activating complement (12). Activation of complement via the alternative pathway has also been... 

In the case of flexible molecules all chiral conformers contribute to the observed CD spectrum. This usually leads to substantial reduction of the magnitude of the exciton Cotton effect. Nevertheless, if the conformation of the main contributor is established independently (e.g.. by molecular mechanics or NMR spectroscopy), its absolute configuration can be deduced from the exciton Cotton effect. Thus, for 3-(l-naphthalenyl)phthalide 5, the preferred conformation is 5 a. The negative couplet is in accordance with the left-handed screw between the phthalide 1 Ld and the naphthalene lBb transition dipole moment vectors, when the absolute configuration is R121. 

The first important invention before the invention of NC NG was the prepn in 1833 of impure Nitrostarch(NS) by Braconnot. The next step was prepn in 1838 by Pelouze of nitrated paper and cotton, but it was not realized that these were actually impure, low nitrogen content, NC s. More important than the work of the above investigators were the prepn in 1846 of NC of high N content (known as Guncotton), independently by C.F. Schonbein (1799 1866) and F. Bottger (1806 1886) and in the same year of NG by an Italian chemist Ascanio Sobrero (1812-1888). The method of prepn and some props of NG were published in France in Feb 1847 by Th-J. Pelouze (1807-1867)... 

Similar curves are obtained with other synthetic polypeptides, and in most cases they are reasonably independent of the nature of the amino acid side chains. In synthetic polypeptides and proteins the observed Cotton effects do not arise from isolated chromophores but are composite curves resulting from several transitions assigned to the amide bonds in the 200-m/x region. The a-helical curve, for example, results from three optically active absorption bands. One around 222 m/ arises from an n — 7T transition of nonbonding electrons, and the other two at 208 and 191 m/ji are attributed to w — tt transitions parallel and perpendicular to the axis of the helix. These transitions of the a-helix and the resulting Cotton effects characteristic of the a-helix are at present of great interest in interpreting ORD curves of membranes. 

At the same time Bottger [6] announced the preparation of an explosive cotton in 1846. This was done independently of Schonbein, and Bottger s priority was admitted by Schonbein [5]. 

In an earlier procedure applying universal calibration, viscosities of the four most concentrated fractions eluting about the peak were measured, and the intrinsic viscosities were plotted against count. The intrinsic viscosities of all the fractions were obtained by extrapolation of the plot for use in the calculations to obtain degree of polymerization (DP). In the present method the DP of each fraction is obtained from the relationship MW = (cod size/K)1/1+ derived from Benoit s concept and the Mark-Houwink equation. Results from the new procedure are in excellent agreement with those obtained independently on cotton by others. Anomalies in results obtained previously on some samples disappear while marked improvement is noted for others. The determination is speeded up greatly by computer processing of data, and experimental error is reduced. 

Cathou et al. (459) found that the Cotton effect near 270 nm in the ORD spectrum of RNase disappeared on interaction with either 2 -CMP or 3 -CMP. The X-ray studies (120) (see Fig. 23) clearly show that no tyrosine residues are in close contact with the substrate. Thus the change in rotatory behavior must reflect either (1) a shift in protein structure on association of the nucleotide or (2) the induction of a Cotton effect of the opposite sign in the bound nucleotide. In the independent spectral and chemical studies of Irie and Sawada (480), the reduced nucleotide 5,6-dihydrouridine-2 (3 )-phosphate, known to interact with the enzyme, showed no difference spectrum. With nucleotides containing... 

The history of modern explosives commenced with the discoveries of nitroglycerin and of nitrocellulose. At about the time that Sobrero first prepared nitroglycerin, Schonbein at Basel and Bottger at Frankfort-on-the-Main independently of each other nitrated cotton, perceived the possibilities in the product, and... 

It is worth emphasizing that all scaling theories (due to de Gennes, Daoud and Cotton, Zhulina and Birshtein, and Halperin) for block copolymer micelles with a small core and large corona predict that the association number and core radius are independent of the coronal chain length. 

Metallisation of fibres is not only a physical process determined by absorption capacity of the fibres for the metal and diffusion capacity of the metal in the fibre structure, but also depends on chemical parameters such as chemical structure of the fibres, presence of functional groups, reactivity of the fibre and the metal, oxidation state of the metal and the presence, necessity and reactivity of supporting chemicals (e.g. reducing agent). Therefore, it was necessary first to study metallisation at different types of fibres in order to investigate which structure is most useful for further research. In this respect, viscose, cotton, natural silk and polyacrylonitrile fibres were investigated because of their different structure and properties and their availability in the New Independent States of the former Soviet Union (Uzbekistan, Kazakhstan, Kyrgyzstan). 

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