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Comparison with room-temperature

In addition, they analyzed the measurements of Taylor, Camac, and Feinberg [217] for CO-NO mixtures. The results are presented in Figure 3.28, taken from their paper. Also shown are the data of Hooker and Millikan [187] for V-T relaxation in CO, along with room-temperature results of Bauer and Roesler [111] and of Basco et al. [180], The dashed lines were calculated by SSH theory [30] [see equation (59)]. The V-T probability for CO-CO collisions is shown by a solid line for comparison. The resulting V-V probabilities are found to be in general agreement with the SSH theory, except for the CO-H2 case. For this pair, rotational energy also contributes to the transfer process, as discussed in Part 4 below. [Pg.244]

Table 8. Comparison of room-temperature conductivity with superconducting critical temperature there is an inverse coirelation ... Table 8. Comparison of room-temperature conductivity with superconducting critical temperature there is an inverse coirelation ...
A very similar method as above [376] was used by Que et al. [377] in which CUCI2 was used as the source of the dopant (Cu) instead of MnClj. A hydrothermal treatment was performed at 120 C/15 h the particle size, estimated by XRD, was about 9 nm. The authors used water-rich compositions in the phase field (system [NP-5 -1- NP-9]/petroleum ether/aqueous solution) for microemulsions with high particle yield. Xu et al [378] extended the same work to the rare earth cation Eu as dopant in ZnS. The particle size varied in the range 3-18 nm. A comparison of room temperature photoluminescence shows the obvious superiority of Eu in the intensity of the luminescence. [Pg.144]

One of our major goals was to make this technology work with room-temperature GaAs lasers. These are small, efficient, can be current modulated, are potentially inexpensive and reliable but have limited power. At present, 10 to 20 mW CW is the most one can expect to achieve reliably. In comparison Nd YAG lasers are bulky, expensive, inefficient, require water cooling and the pump-lamps have limited lifetime. In addition, an expensive modulator (e.g., acousto-optic) is needed for the LV system. [Pg.224]

Figure 24.6 Comparison of room-temperature TH F absorption as a function ofimmersion timeof an epoxy resin control with epoxy/silica particulate nanocomposite and epoxy/silica hybrid (bicontinuous nanocomposite). Figure 24.6 Comparison of room-temperature TH F absorption as a function ofimmersion timeof an epoxy resin control with epoxy/silica particulate nanocomposite and epoxy/silica hybrid (bicontinuous nanocomposite).
FIGURE 16 Comparison of room temperature resistivities of various forms of carbon with other materials [55]. [Pg.220]

The comparisons between different types of fibres that were treated similarly indicate that the composites produced may have a similar flexural strength, but may be quite different in toughness (Table 11.3) [26,29]. These differences cannot be explained on the basis of density (which is similar in all the specimens), or the geometry (aspect ratio) of the fibre, which is highest for the fibre which led to the composite of lowest toughness (Table 11.3). Similar trends were reported by Coutts [30] for softwood and hardwood fibres prepared with room temperature cured matrix. There, the better performance of the softwood fibres was attributed to the higher fibre aspect ratio. [Pg.441]

Ji X, Banks CE, Silvester DS, Aldous L, Hardacre C, Compton RG (2007) Electrochemical ammonia gas sensing in nonaqueous systems a comparison of propylene carbonate with room temperature ionic liquids. Electroanalysis 19 2194-2201... [Pg.389]

A brief review has appeared covering the use of metal-free initiators in living anionic polymerizations of acrylates and a comparison with Du Font s group-transfer polymerization method (149). Tetrabutylammonium thiolates mn room temperature polymerizations to quantitative conversions yielding polymers of narrow molecular weight distributions in dipolar aprotic solvents. Block copolymers are accessible through sequential monomer additions (149—151) and interfacial polymerizations (152,153). [Pg.170]

Electrochemical treatment of the polymers in nitric acid in the absence of silver ions was carried out at room temperature. Extent of oxidation was low for hd-PE and PP. It was not possible to directly compare the results with those obtained for oxidation in the presence of silver ions since different temperatures were used (room temperature versus 60°C). However, the spectra obtained after treatment indicated similar chemical effects for the two cases. For PS, it was possible to make direct comparisons because the same temperature was used for treatment in the presence and absence of silver ions. In that case, the overall degree of oxidation was lower. [Pg.309]

Triflates of aluminum, gallium and boron, which are readily available by the reaction of the corresponding chlorides with triflic acid, are effective Fnedel-Crafis catalysis for alkylation and acylation of aromatic compounds [119, 120] Thus alkylation of toluene with various alkyl halides m the presence of these catalysts proceeds rapidly at room temperature 111 methylene chloride or ni-tromethane Favorable properties of the triflates in comparison with the correspond mg fluorides or chlorides are considerably decreased volatility and higher catalytic activity [120]... [Pg.964]

As already mentioned, there is a striking difference in the reactivity of 1- and 3-chloroisoquinoline the former reacts about 10 times faster than the latter with both piperidine and ethoxide ion at room temperature. The lower rate of ethoxy-dechlorination of the 3-isomer is due to an E which is 10 kcal higher. It is not justified to conclude that this isomer is virtually unactivated when its rate of ethoxylation is 100,000 times that of 2-chloronaphthalene and the E for this reaction is markedly decreased (by 7 kcal) relative to that of 2-chloronaphthalene. A direct comparison of reactivity with piperidine has not been made, but a rate ratio of 500 1 can be estimated by using a factor of one-fortieth (Table X, lines 1 and 4) to make the... [Pg.349]

Phase composition and grain structure of Ti-6Al-2Zr-l.5V-lMo-0.35H alloy after heat treatment and after deformation were studied in comparison with the basic alloy. After hydrogenation and cooling to room temperature the structure of the specimens was a -martensite with 20-25% of the / -phase. [Pg.431]

As methyl alcohol freezes in the neighborhood of — 95°C, measurements at a temperature — 70°C would be comparable with water at room temperature at 25°C methyl alcohol is very unlike water, having a compressibility more than 2.5 times as large. Ethyl alcohol and liquid ammonia are likewise unsuitable for comparison with wat er. [Pg.187]

Figure 15-13. (a) Pholocurrenl action spectra at room temperature for a thick photodiode (ITO/780 nm MEH-PPV/A1) under illumination through the ITO electrode, under forward bias (dash dot) and reverse bias (solid line), with the room temperature absorption spectrum (dashed line) shown for comparison. (b) Pholocurrenl action spectra at room temperature for a thin photodiode (ITO/120 nm MEH-PPV/A1) under illumination through the ITO electrode, under forward bias (dash dot line) and reverse bias (solid line), with the room temperature absorption spectrum (dashed line) shuwn for comparison (reproduced by permission of the American Physical Society from Ref. 176)). [Pg.280]

Comparison of the results obtained by the redrying procedure with those by the primary reference method (room temperature, in vacuo over magnesium perchlorate) is shown in Table II. The agreement of the two sets of results was within 0.2% or better, which is considered satisfactory and serves to confirm the suitability of the redrying procedure as a secondary reference standard. [Pg.45]


See other pages where Comparison with room-temperature is mentioned: [Pg.79]    [Pg.244]    [Pg.469]    [Pg.79]    [Pg.244]    [Pg.469]    [Pg.337]    [Pg.113]    [Pg.78]    [Pg.700]    [Pg.607]    [Pg.350]    [Pg.798]    [Pg.261]    [Pg.265]    [Pg.228]    [Pg.80]    [Pg.312]    [Pg.224]    [Pg.131]    [Pg.286]    [Pg.235]    [Pg.32]    [Pg.383]    [Pg.437]    [Pg.151]    [Pg.542]    [Pg.427]    [Pg.659]    [Pg.104]    [Pg.729]    [Pg.53]    [Pg.1030]    [Pg.909]    [Pg.187]    [Pg.4]    [Pg.222]   


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Room temperature

Temperature comparison

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