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Initiatives worker

A somewhat different conclusion follows if we introduce technical progress. In that case, the surplus reinvested might actually benefit the workers in the form of an increase in the real wage. If initially workers live by bread alone, reinvestment of the surplus may in part go to caviar for the capitalist, but in part also to butter for the workers, not only to bread... [Pg.178]

Unfortunately for this concept, and despite several attempts (including efforts by one of the initial workers), auxins a and b have never been reisolated. Furthermore, recent studies also cast doubt on the chemical struc-... [Pg.123]

Some mention should be made of perhaps the major topic of conversation among surface and colloid chemists during the period 1966-1973. Some initial observations were made by Shereshefsky and co-workers on the vapor pressure of water in small capillaries (anomalously low) [119] but especially by Fedyakin in 1962, followed closely by a series of papers by I>eijaguin and co-workers (see Ref. 120 for a detailed bibliography up to 1970-1971). [Pg.248]

A very different nucleation scheme by Grieser and co-workers employs ultrasonic irradiation of salt solutions to create H- and OH- radicals in solution [73]. These radicals proceed to nucleate growth of quantum-sized (Q-state) particles of cadmium sqlfide. Similar initiation has been used for polymer latices [74]. [Pg.338]

Exerowa and co-workers [201] suggest that surfactant association initiates black film formation the growth of a black film is discussed theoretically by de Gennes [202]. A characteristic of thin films important for foam stability, their permeability to gas, has been studied in some depth by Platikanov and co-workers [203, 204]. A review of the stability and permeability of amphiphile films is available [205]. [Pg.522]

Rate effects may not be chemical kinetic ones. Benson and co-worker [84], in a study of the rate of adsorption of water on lyophilized proteins, comment that the empirical rates of adsorption were very markedly complicated by the fact that the samples were appreciably heated by the heat evolved on adsorption. In fact, it appeared that the actual adsorption rates were very fast and that the time dependence of the adsorbate pressure above the adsorbent was simply due to the time variation of the temperature of the sample as it cooled after the initial heating when adsorbate was first introduced. [Pg.661]

To detect tlie initial apparent non-RRKM decay, one has to monitor the reaction at short times. This can be perfomied by studying the unimolecular decomposition at high pressures, where collisional stabilization competes with the rate of IVR. The first successful detection of apparent non-RRKM behaviour was accomplished by Rabinovitch and co-workers [115], who used chemical activation to prepare vibrationally excited hexafluorobicyclopropyl-d2 ... [Pg.1035]

In an extension of traditional CIDNP methods, Closs and co-workers developed time-resolved CIDNP (TR-CIDNP) m the late 1970s [24, 25 and 26]. The initial time-resolved experiments had a time resolution in the... [Pg.1603]

Utilizing FT-EPR teclmiques, van Willigen and co-workers have studied the photoinduced electron transfer from zinc tetrakis(4-sulfonatophenyl)porphyrin (ZnTPPS) to duroquinone (DQ) to fonn ZnTPPS and DQ in different micellar solutions [34, 63]. Spin-correlated radical pairs [ZnTPPS. . . DQ ] are fomied initially, and the SCRP lifetime depends upon the solution enviromnent. The ZnTPPS is not observed due to its short T2 relaxation time, but the spectra of DQ allow for the detemiination of the location and stability of reactant and product species in the various micellar solutions. While DQ is always located within the micelle, tire... [Pg.1614]

So far we have exclusively discussed time-resolved absorption spectroscopy with visible femtosecond pulses. It has become recently feasible to perfomi time-resolved spectroscopy with femtosecond IR pulses. Flochstrasser and co-workers [M, 150. 151. 152. 153. 154. 155. 156 and 157] have worked out methods to employ IR pulses to monitor chemical reactions following electronic excitation by visible pump pulses these methods were applied in work on the light-initiated charge-transfer reactions that occur in the photosynthetic reaction centre [156. 157] and on the excited-state isomerization of tlie retinal pigment in bacteriorhodopsin [155]. Walker and co-workers [158] have recently used femtosecond IR spectroscopy to study vibrational dynamics associated with intramolecular charge transfer these studies are complementary to those perfomied by Barbara and co-workers [159. 160], in which ground-state RISRS wavepackets were monitored using a dynamic-absorption technique with visible pulses. [Pg.1982]

To make a clearer connection to the molecular dynamics, this expression can be transfomied to the time domain. In this picture, which was initially developed by Heller and co-workers [132,133], the absorption spectrum is given by the expression... [Pg.269]

A combination of the promoting effects of Lewis acids and water is a logical next step. However, to say the least, water has not been a very popular medium for Lewis-acid catalysed Diels-Alder reactions, which is not surprising since water molecules interact strongly with Lewis-acidic and the Lewis-basic atoms of the reacting system. In 1994, when the research described in this thesis was initiated, only one example of Lewis-acid catalysis of a Diels-Alder reaction in water was published Lubineau and co-workers employed lanthanide triflates as a catalyst for the Diels-Alder reaction of glyoxylate to a relatively unreactive diene . No comparison was made between the process in water and in organic solvents. [Pg.31]

In addition to the initial reaction between nitric acid and acetic anhydride, subsequent changes lead to the quantitative formation of tetranitromethane in an equimolar mixture of nitric acid and acetic anhydride this reaction was half completed in 1-2 days. An investigation of the kinetics of this reaction showed it to have an induction period of 2-3 h for the solutions examined ([acetyl nitrate] = 0-7 mol 1 ), after which the rate adopted a form approximately of the first order with a half-life of about a day, close to that observed in the preparative experiment mentioned. In confirmation of this, recent workers have found the half-life of a solution at 25 °C of 0-05 mol 1 of nitric acid to be about 2 days. ... [Pg.81]

Gassman and co-workers developed a synthetic route from anilines to indoles and oxindoles which involves [2.3]-sigmatropic rearrangement of anilinosul-fonium ylides. These can be prepared from Ai-chloroanilines and ot-thiomcthyl-ketones or from an aniline and a chlorosulfonium salt[l]. The latter sequence is preferable for anilines with ER substituents. Rearrangement and cyclizalion occurs on treatment of the anilinosulfonium salts with EtjN. The initial cyclization product is a 3-(methylthio)indole and these can be desulfurized with Raney nickel. Use of 2-(methylthio)acetaldehyde generates 2,3-unsubstituled indoles after desulfurization[2]. Treatment of 3-methylthioindoles with tri-fiuoroacetic acid/thiosalieylie acid is a possible alternative to Raney nickel for desulfurization[3]. [Pg.71]

R. K. Jackson and co-workers, "Initiation and Detonation Characteristics of TATB," in Proceedings of Symposium on Compatibility of Plastics and Other Materials with Explosives, Propellants, and Pyrotechnics, ADPA, Washington, D.C., 1976. [Pg.29]

C. D. Hutchinson and co-workers, "Initiation and Detonation Properties of the Insensitive High Explosive TATB/KEL-F800 95/5," Vol. 1, in... [Pg.29]

Coal, considered a soHd hydrocarbon with a generic formula of CHq g, was explored by numerous workers (24—31) as a feedstock for the production of acetylene. Initially, the motivation for this work was to expand the market for the use of coal in the chemical process industry, and later when it was projected that the cost of ethylene would increase appreciably if pretroleum resources were depleted or constrained. [Pg.391]

K. L. Biringer and co-workers. Tower System Requirements and Selection for the Space Exploration Initiative, SAND-91-1593C, Sandia National Laboratories, N.M., 1991. [Pg.205]

During the 1970s and 1980s, U.S. companies tried to adopt Japanese improvement techniques, but not the philosophy. Thus quahty circles, ie, problem-solving groups of production workers, were initiated (11,12). When this approach failed to achieve anticipated results, it was replaced by other techniques, such as SPG (13), JIT (14), and ZD. This use of contrasting approaches has been summarized (15). [Pg.366]

The initial production of GR-S mbber required a learning period in processing before mbber workers were comfortable with the new synthetic mbber. Although softer and more plastic initially, the GR-S did not break down as much as natural mbber. Once familiar with the differences, processing GR-S was handled quite comfortably. The same was tme when the cold GR-S was introduced, followed by the oil-extended version, and SSBR. [Pg.498]

Brysson and co-workers (7) conducted a study in St. Louis, Missouri, on the effects of urban air pollution on the tensile strength of cotton duck material. Samples were exposed at seven locations for up to 1 year. Figure 9-3 shows the relationship between tensile strength and pollutant exposure. For two levels of ambient air exposure, the materials exhibited less than one-half their initial tensile strength when exposed to air pollution for 1 year. [Pg.131]


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See also in sourсe #XX -- [ Pg.209 ]




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