Spontaneous mass generation

In the real world the stress tensor never vanishes and so requires a nonvanishing curvature tensor under all circumstances. Alternatively, the concept of mass is strictly undefined in flat Minkowski space-time. Any mass point in Minkowski space disperses spontaneously, which means that it has a space-like rather than a time-like world line. In perfect analogy a mass point can be viewed as a local distortion of space-time. In euclidean space it can be smoothed away without leaving any trace, but not on a curved manifold. Mass generation therefore resembles distortion of a euclidean cover when spread across a non-euclidean surface. A given degree of curvature then corresponds to creation of a constant quantity of matter, or a constant measure of misfit between cover and surface, that cannot be smoothed away. Associated with the misfit (mass) a strain field appears in the curved surface. 

The Cardiac Cycle. The heart (Eig. lb) performs its function as a pump as a result of a rhythmical spread of a wave of excitation (depolarization) that excites the atrial and ventricular muscle masses to contract sequentially. Maximum pump efficiency occurs when the atrial or ventricular muscle masses contract synchronously (see Eig. 1). The wave of excitation begins with the generation of electrical impulses within the SA node and spreads through the atria. The SA node is referred to as the pacemaker of the heart and exhibits automaticity, ie, it depolarizes and repolarizes spontaneously. The wave then excites sequentially the AV node the bundle of His, ie, the penetrating portion of the AV node the bundle branches, ie, the branching portions of the AV node the terminal Purkinje fibers and finally the ventricular myocardium. After the wave of excitation depolarizes these various stmetures of the heart, repolarization occurs so that each of the stmetures is ready for the next wave of excitation. Until repolarization occurs the stmetures are said to be refractory to excitation. During repolarization of the atria and ventricles, the muscles relax, allowing the chambers of the heart to fill with blood that is to be expelled with the next wave of excitation and resultant contraction. This process repeats itself 60—100 times or beats per minute... 

With TSP, ammonium acetate has emerged as the best general-purpose electrolyte for ionizing neutral samples. Improved ionization can be obtained by the use of a filament or discharge electrode to generate reactive ions for CI (87, 88). The processes involved in filament or discharge-assisted ionization must be used when operating in the absence of a buffer with nonaqueous eluents. With ionic analytes, the mechanism of ion evaporation is supposed to be primarily operative since ions are produced spontaneously from the mobile phase (89). Ion evaporation often yields mass spectra with little structural information in order to overcome this problem, other ionization modes or tandem MS have been applied (90). 

Insufficient mixing may easily result in a low nitration rate owing to the small interfacial area. It can also lead to a non-uniform nitration process. Owing to inadequate construction of the stirrer, too low a speed of rotation, or an interruption in stirring, so-called dead spaces may easily be formed in which non nitrated or not fully nitrated substances accumulate. If a rather large quantity of the mixture is stirred suddenly, rapid extension of the interfacial area takes place, followed by the generation of large amounts of heat and a rise in temperature. This may cause a spontaneous decomposition of the reaction mass in the nitrator, and then an explosion. 

Anionic PO polymerisation consists of the PO addition to the starter, at 105-125 °C and 0.3-0.5 MPa. The flow of PO addition is the flow required to maintain the pressure and temperature of the reaction constant, in the stated range. PO, having a low boiling point (bp = 33.6 °C), is volatilised spontaneously by the simple contact with the hot reaction mass at 105-125 °C and generates a pressure. PO is consumed in the polymerisation reaction and a high volatile monomer, PO, is transformed into a compound with a very low volatility the polyether. As an immediate consequence of PO consumption in the reaction, the pressure has a tendency to decrease and, in order to maintain the pressure constant, PO is continuously added. Of course the temperature is maintained within the required range by continuous elimination of the reaction heat by cooling. 

---