Hydrogen, characteristic temperature

Vanadium oxytrichloride is a lemon-yellow liquid. Its boiling point is 124.5°C. at 736 mm. and 127.16°C. at 760 mm. It remains liquid at —77°. The vapor pressure at —77° is 4.1 mm. at 0°, 21 mm. and at 85°C., 270 mm. Its density in grams per milliliter is 1.854 at 0° and 1.811 at 32°C. At ordinary temperatures, it neither dissolves nor reacts with carbon, hydrogen, nitrogen, oxygen, silicon, tellurium, or metals except the alkali metals and antimony. The reactions with the alkali metals are explosive at characteristic temperatures, varying from 30°C. for cesium to 180°C. for sodium (lithium not determined). Small... 

The liquid product obtained from acetylene and hydrogen at temperatures not above 200° is fluorescent, not attacked appreciably by a mixture of sulphuric and nitric acids, and presents the characteristics of American petroleum, Acetylene alone, yields a green-coloured liquid which resembles Russian petroleum. 

The developed mathematical model has been applied for calculation of processes in MHHP intended for vehicle air conditioning [4, 7]. Study of influence of the basic heat pump parameters (pressure of hydrogen charging, temperatures and coolant consumption, cycle time) on its power characteristics has been carried out. It was shown that the estimated data well agreed with experimental results. It was found that the developed model could be used for qualitative investigation of various parameters influence and approximate quantitative assessments. 

It is necessary to acknowledge that some existing experimental data indicates that oxygen can be removed from Li/MgO directly during the reduction in hydrogen at temperatures as low as 873 K (see, for instance, Leveies, 2002). Such discrepancies with the data described above might be due to some difference in catalyst preparation/pretreatment procedures, which leads to the formation of active sites with somewhat different thermochemical characteristics. What is important is to attribute the evaluated kinetic parameters to the catalysts of particular thermochemistry. 

Due to the two strong n-accepting NO ligands and the two o-donating phosphines, a characteristic hydridic reactivity is expected for the metal bonded hydrogen. Indeed, temperature-dependent measurements of the DQCC revealed high bond ionicities of 72% for 31a and 70% for 34b, respectively. 

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