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At room temperature

However, if the liquid solution contains a noncondensable component, the normalization shown in Equation (13) cannot be applied to that component since a pure, supercritical liquid is a physical impossibility. Sometimes it is convenient to introduce the concept of a pure, hypothetical supercritical liquid and to evaluate its properties by extrapolation provided that the component in question is not excessively above its critical temperature, this concept is useful, as discussed later. We refer to those hypothetical liquids as condensable components whenever they follow the convention of Equation (13). However, for a highly supercritical component (e.g., H2 or N2 at room temperature) the concept of a hypothetical liquid is of little use since the extrapolation of pure-liquid properties in this case is so excessive as to lose physical significance. [Pg.18]

Carbon dioxide, COj. Sublimes — 78 5 C. A colourless gas at room temperature, occurs naturally and plays an important part in animal and plant respiration. Produced by the complete combustion of carbon-containing materials (industrially from flue gases and from synthesis gas used in ammonia production) and by heating metal carbonates or by... [Pg.81]

Carbon suboxide, C3O2, OCCCO. M.p. — 107 C, b.p. 6-8°C. A toxic gas (malonic acid plus P2O5) which polymerizes at room temperature. Reforms malonic acid with water. [Pg.82]

Cyanogen fluoride, FCN. Colourless gas (b.p. — 46 C) prepared by pyrolysis of cyanuric fluoride. Polymerizes to (FCN), cyanuric fluoride, at room temperature. [Pg.120]

Residual austenite is a steel structure which during cooling at martensite transformation temperature is not completely converted into martensite and remains unchanged at room temperature together with martensite. [Pg.18]

Specimens used in tests were sections of cables with PVC outer coating. PVC was plasticized with DOF softener. The materials considered were exposed to the radiation and thermal aging. The samples have been irradiated at room temperature by hard gamma rays with 10 rad/sec dose power. A number of samples had been heated for long different times at 90°C. Besides a special specimens were cut out from outer coating for test on tensile machine like "Instron". The total doses of irradiation, times of heating and elongations at break obtained with "Instron" are listed in Table 1. [Pg.244]

For vapor saturated with respect to liquid water at room temperature, Z is about 0.02 mol/cm sec or about 1.2 X 10 molecules/cm sec. At equilibrium, then, the evaporation rate must equal the condensation rate, which differs from... [Pg.56]

There is also a traffic between the surface region and the adjacent layers of liquid. For most liquids, diffusion coefficients at room temperature are on the order of 10 cm /sec, and the diffusion coefficient is related to the time r for a net displacement jc by an equation due to Einstein ... [Pg.57]

This means that the potential some distance away appears to follow Eq. V-13, but with an apparent value of AkTjze, which is independent of the actual value. For monovalent ions at room temperature this apparent would be 100 mV. [Pg.173]

For a free energy of fonnation, the preferred standard state of the element should be the thennodynamically stable (lowest chemical potential) fonn of it e.g. at room temperature, graphite for carbon, the orthorhombic crystal for sulfiir. [Pg.367]

One might also note that this is one of the very few equilibria involving only gaseous species at room temperature that have constants K anywhere near unity.)... [Pg.368]

These results do not agree with experimental results. At room temperature, while the translational motion of diatomic molecules may be treated classically, the rotation and vibration have quantum attributes. In addition, quantum mechanically one should also consider the electronic degrees of freedom. However, typical electronic excitation energies are very large compared to k T (they are of the order of a few electronvolts, and 1 eV corresponds to 10 000 K). Such internal degrees of freedom are considered frozen, and an electronic cloud in a diatomic molecule is assumed to be in its ground state f with degeneracy g. The two nuclei A and... [Pg.405]

Now, typical Femii temperatures in metals are of the order of 50 000 K. Thus, at room temperature, TIT is very small compared to one. So, one can ignore the T dependence of p, to obtain... [Pg.432]

Bohme D K and Raksit A B 1984 Gas phase measurements of the influence of stepwise soivation on the kinetics of nucieophiiic dispiacement reactions with CHjCi and CHjBr at room temperature J. Am. Ghem. Soc. 106 3447-52... [Pg.827]

Another example of epitaxy is tin growdi on the (100) surfaces of InSb or CdTe a = 6.49 A) [14]. At room temperature, elemental tin is metallic and adopts a bet crystal structure ( white tin ) with a lattice constant of 5.83 A. However, upon deposition on either of the two above-mentioned surfaces, tin is transfonned into the diamond structure ( grey tin ) with a = 6.49 A and essentially no misfit at the interface. Furtliennore, since grey tin is a semiconductor, then a novel heterojunction material can be fabricated. It is evident that epitaxial growth can be exploited to synthesize materials with novel physical and chemical properties. [Pg.927]

The first step consists of the molecular adsorption of CO. The second step is the dissociation of O2 to yield two adsorbed oxygen atoms. The third step is the reaction of an adsorbed CO molecule with an adsorbed oxygen atom to fonn a CO2 molecule that, at room temperature and higher, desorbs upon fomiation. To simplify matters, this desorption step is not included. This sequence of steps depicts a Langmuir-Hinshelwood mechanism, whereby reaction occurs between two adsorbed species (as opposed to an Eley-Rideal mechanism, whereby reaction occurs between one adsorbed species and one gas phase species). The role of surface science studies in fomuilating the CO oxidation mechanism was prominent. [Pg.953]

The unique feature in spontaneous Raman spectroscopy (SR) is that field 2 is not an incident field but (at room temperature and at optical frequencies) it is resonantly drawn into action from the zero-point field of the ubiquitous blackbody (bb) radiation. Its active frequency is spontaneously selected (from the infinite colours available in the blackbody) by the resonance with the Raman transition at co - 0I2 r material. The effective bb field mtensity may be obtained from its energy density per unit circular frequency, the... [Pg.1197]

Motion, and in particular diffiision, causes a further limit to resolution [14,15]. First, there is a physical limitation caused by spins diflfiising into adjacent voxels durmg the acquisition of a transient. For water containing samples at room temperature the optimal resolution on these grounds is about 5 pm. However, as will be seen in subsequent sections, difhision of nuclei in a magnetic field gradient causes an additional... [Pg.1529]

Figure Bl.15.6. The EPR spectrum of tire perinaphthenyl radical in mineral oil taken at room temperature. (A) First derivative of the EPR absorption x with respect to the external magnetic field, Bq. (B) Integrated EPR spectrum. Figure Bl.15.6. The EPR spectrum of tire perinaphthenyl radical in mineral oil taken at room temperature. (A) First derivative of the EPR absorption x with respect to the external magnetic field, Bq. (B) Integrated EPR spectrum.
Figure Bl.16.2. X-band TREPR spectra obtained at 0.1 ps after 308 mn photolysis of a fliiorinated peroxide dimer in Freon 113 at room temperature. Part A is the A/E RPM spectrum obtained upon direct photolysis part B is the E/A RPM spectrum obtained upon triplet sensitization of this reaction using benzophenone. Figure Bl.16.2. X-band TREPR spectra obtained at 0.1 ps after 308 mn photolysis of a fliiorinated peroxide dimer in Freon 113 at room temperature. Part A is the A/E RPM spectrum obtained upon direct photolysis part B is the E/A RPM spectrum obtained upon triplet sensitization of this reaction using benzophenone.
Figure Bl.16.18. TREPR spectra observed after laser excitation of tetraphenylhydrazine in an SDS micelle at room temperature. Reprinted from [61]. Figure Bl.16.18. TREPR spectra observed after laser excitation of tetraphenylhydrazine in an SDS micelle at room temperature. Reprinted from [61].
Figure Bl.16.19. (a) CIDEP spectrum observed in die photolysis of xanthone (1.0 x 10 M) in cyclohexanol at room temperature. The stick spectra of the ketyl and cyclohexanol radicals with RPM polarization are presented, (b) CIDEP spectrum after the addition of hydrochloric acid (4.1 vol% HCl 0.50 M) to the solution above. The stick spectra of the ketyl and cyclohexanol radicals with absorptive TM polarization are presented. The bold lines of the stick spectra of the cyclohexanol radical show the broadened lines due to ring motion of the radical. Reprinted from [62]. Figure Bl.16.19. (a) CIDEP spectrum observed in die photolysis of xanthone (1.0 x 10 M) in cyclohexanol at room temperature. The stick spectra of the ketyl and cyclohexanol radicals with RPM polarization are presented, (b) CIDEP spectrum after the addition of hydrochloric acid (4.1 vol% HCl 0.50 M) to the solution above. The stick spectra of the ketyl and cyclohexanol radicals with absorptive TM polarization are presented. The bold lines of the stick spectra of the cyclohexanol radical show the broadened lines due to ring motion of the radical. Reprinted from [62].

See other pages where At room temperature is mentioned: [Pg.15]    [Pg.25]    [Pg.30]    [Pg.75]    [Pg.109]    [Pg.123]    [Pg.199]    [Pg.228]    [Pg.277]    [Pg.303]    [Pg.347]    [Pg.258]    [Pg.258]    [Pg.259]    [Pg.439]    [Pg.87]    [Pg.303]    [Pg.484]    [Pg.489]    [Pg.500]    [Pg.809]    [Pg.812]    [Pg.934]    [Pg.940]    [Pg.1468]    [Pg.1569]    [Pg.1591]    [Pg.1634]    [Pg.1682]   
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