CO2, atmosphere

Cychc carbonates are produced ia high yield under very mild conditions by treating chlorohydrins with tetramethylammonium hydrogen carbonate ia acetonitrile [75-05-8] under a CO2 atmosphere (38). 

Chemical Properties. When heated in a dry CO2 atmosphere, sodium cyanide fuses without much decomposition. A brown-black color... 

Vanadium (III) acetonylacetonate [13476-99-8] M 348.3, m 181-184°, 185-190°, pKj 2.92, pK 3.5(for aquo V hydrolysis). Crystd from acetylacetone as brown plates. It can be distilled in small quantities without decomposition. It is soluble in CHCI3 and CgHg and evaporation of a CHCI3 solution yields brown crystals which are washed with cold EtOH and dried in vacuum or at 100° in a CO2 atmosphere. Under moist conditions it readily oxidises [V(AcAc)3 lo V(AcAc)20]. [J Chem Soc 103 78 1913, Inorg Synth 5 105 1957 Anal Chem 30 526 I958 UV J Am Chem Soc 80 5686 1958.]... 

Syoichi, Y. et ah, Aromatization of Propane in CO2 Atmosphere, Second Joint Saudi Japanese Workshop on Recent Developments in Selected Petroleum Refining and Petrochemical Processes, KFUPM, Dhahran, Saudi Arabia, 12-13, Dec. 1992. 

Extraction of luciferin with methanol from Cypridina frozen with dry ice. The chunks of frozen Cypridina are crushed into small pieces, and extracted with methanol with stirring. Small pieces of dry ice are added as needed to keep the temperature slightly below 0°C and also to prevent the oxidation of luciferin in a CO2 atmosphere. Luciferin is easily extracted into methanol. The mixture is filtered on a Buchner funnel (with suction), protecting the luciferin in a CO2 atmosphere by addition of small pieces of dry ice as needed. 

In the case of 271a and 271b, covalently bound adducts of 271a, b and CO2 (e. g., carbamic acid derivatives) were detected. This was absent in the case of thiol derivative 271c. The concentration of this material could be reduced by heating (a solution to 90 °C for 1 h) and increased by exposing to a CO2 atmosphere. 

R = t-Bu, 81%) and r-butylbenzene (5%) (Scheme 119) [447]. Similarly, the Pd(II) complex catalyzes the electrosynthesis of aromatic carboxylic acids under CO2 atmosphere [448]. The electrocar-boxylation of vinyl triflates is performed with CO2 and a catalytic amount of PdCl2(PPh3)2 to give a,/ -unsaturated carboxylic acids [449]. 

Violanthrene (dibenzanthrene) [81-31-2] M 428.5. Purified by vacuum sublimation over Cu in a muffle furnace at 450°/25mm in a CO2 atmosphere [Scholl and Meyer B 67 1229 1934. ... 

Glasner et al. [399], however, showed that Eu2(Ox)3 behaves somewhat differently from other rare earth oxalates, in being easily reduced to the divalent state. According to these investigators, the first step of the thermal decomposition of Eu2(Ox)3 at 320° C in a CO2 atmosphere involves the formation of Eu(Ox) with a weight loss of 28.6 per cent. In an oxidizing atmosphere, however, reoxidation takes place, and the final... 

Clair, T. A., J. M. Ehrman, and K. Higuchi. 1999. Changes in freshwater carbon exports from Canadian terrestrial basins to lakes and estuaries under a 2 x CO2 atmospheric scenario. 

A cold early climate and a thin CO2 atmosphere are consistent with the ubiquity of primary igneous minerals and the apparent absence of secondary minerals and copious carbonates on the surface. Aqueous eruptions introduced soluble chloride and sulfate salts into Martian soils, leaving clays and carbonates within the crust. If the Martian crust hosts a deep biosphere, aqueous eruptions could bring organisms or their chemical signature to the surface. The biotic component of any recent eruptions may be preserved in transient ice in cold traps on the surface. 

For the samples of CHAp-A prepared by high temperature treatment (900 °C) of HAp in CO2 atmosphere, the 13C MAS spectrum would have a sharp resonance at 166.5 ppm with a full width at half maximum (FWHM) of about 1 ppm.88 Interestingly, a total of four peak components was found in the 31P MAS spectrum, ranging from 2.5 to 5.5 ppm 31 For the samples of CHAp-B prepared by wet chemistry at 80 °C and those of CHAp-AB prepared by thermal crystallization of carbonated ACP at 500—600 °C, both of their 13C MAS spectra contain peak components... 

The rat is placed in a dorsal position on an undersheet and the fur is moistened with ethanol/water. The abdominal cavity is opened and the abdominal wall folded back. The uterus is exposed and the amniotic fluid is withdrawn by puncturing the amniotic sac with a syringe. The uterus is then placed on a plastic film and opened. The placentas with the fetuses are detached from the uterus. The placentas are then detached from the fetuses. After removing the fetal membranes the fetuses are removed and immediately killed under CO2 atmosphere. The amniotic fluid is aspirated with a disposable syringe. 

F-treated intermetallics exhibit extremely high reactivity and selectivity to H2, even in CO and CO2 atmospheres. The treatment behaves as a curing effect of the external surface and creates a fluoride-rich layer with a Ni-enriched subsuperficial layer. The hydriding behavior is increased by the presence of microcracks running through the external layer the initial activation process is enhanced, even for Mg-based alloys. In addition, a protective effect is observed since the samples can be safely stored in air for long time without degradation or surface reactivity [116]. 

FIGURE 5.10 Rate of CaCOa decomposition in CO2 atmosphere. From Hyatt et al. [16]. Reprinted by permission of the American Ceramic Society. 

Figure 4.3-5 Rotation-vibration band v2) of atmospheric CO2 (atmospheric pressure 1000 hPa, 25 °C, 400 cm) at a spectral resolution of 0.05 cm (for a discussion of the Q-branches marked by an asterisk see text).

Fujita et al. (89-91) reported that 16 is produced by irradiating the rhenium dimer complex, (COsldmblRe—Re(dmb)(CO)3, in THF under a CO2 atmosphere. This reaction has been reported to proceed by the reaction between CO2 and the 17-electron species [Re(dmb)(CO)3] generated by light-induced homolysis of the dimer (see Section III.B for homolysis of the Re—Re bond). The photoreaction of (CO)3(dmb)Re—CO2—Re(dmb)(CO)3 with CO2 quantitatively 5nelded CO and C03. ... 

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