Complete fusion

Sintering consists of heating a mixture of fine materials to an elevated temperature without complete fusion. Surface diffusion and some incipient fusion cause the soHd particles in contact with one another to adhere and form larger aggregates. In the processing of hematite, Fe202, or magnetite,... 

These are produced by bombarding Th or U with 100-MeV protons, or lighter targets with 100-MeV heavier ions produced in cyclotrons or linear accelerators. Thus the complete fusion of targets such as Pb, Au or T1 with the projeetiles B, C, O, N or Ne produces Fr isotopes below mass number 223. 

However, an alternative pathway that bypasses clathrin-mediated endocytosis and EEs appears to be available as well. This model of endocytosis known as kiss and run or its variant kiss and stay have attracted increasing interest in recent years [74] (Fig. 9-9B). Kiss and run has been directly demonstrated with dense-core granules in neuroendocrine cells [84, 85], and this model would explain some observations that are not readily accommodated by the classical pathway. The kiss and run model proposes that neurotransmitters are released by a transient fusion pore, rather than by a complete fusion with integration of the synaptic vesicle components into the plasma membrane. Synaptic membrane proteins never lose their association and the vesicle reforms when the pore closes. As a result, the empty vesicle can be refilled and reused without going through clathrin-mediated endocytosis and sorting in the EEs. 

Heat 1 g Cl-acetone and 7 g 2,5-dimethoxyaniline (or analog) at boiling until complete fusion then one-half hour at 180° on a metal bath. Cool, dissolve in a little ethanol and pour into 100 ml 7% HC1. Cool, filter and dry (can distill 100/.001) to get 160 mg 4,7-dimethoxy-2-methylindole (recrystallize-benzeneipetroleum ether, 1 1). 

From the almost entire absence of day in this fritted composition, the mixture must altogether be excluded from clay wares, being in fact neither more nor less than glass mixture, which, if submitted to complete fusion, would yield an alkaline glaBS. The heat, however, to which this mixture is axpoeed only admits of a. partial... 

CRYOHYDRATE. An eutectic system consisting of a salt and water, having a concentration at which complete fusion or solidification occurs al a definite temperature (eutectic temperature) as if only one substance were present. 

The synthesis reactions used to discover the transuranium elements are given in Table 15.2. All these reactions are complete fusion reactions in which the reacting nuclei fuse, equilibrate, and deexcite in a manner independent of their mode of formation. Other production reactions involving a partial capture of the projectile nucleus are also possible. 

The cross section for production of a heavy evaporation residue, ctEVr, by a complete fusion reaction can be written as ... 

When these heavy recoil nuclei are the result of a complete fusion of the projectile and target nuclei, they are usually called evaporation residues because they result from a deexcitation of the primary complete fusion product by particle evaporation (emission). In intermediate energy and relativistic nuclear collisions, the momentum transfer to the target nucleus is much less, and the energy of the recoiling nucleus is 5-100 keV/nucleon. Such recoils are usually called heavy residues ... 

There was also great uncertainty of the production yields for SHEs. Closely related to the fission probability of SHEs in the ground-state, the survival of the compound nuclei formed after complete fusion was difficult to predict. Even the best choice of the reaction mechanism, fusion or transfer of nucleons, was critically debated. However, as soon as experiments could be performed without technical limitations, it turned out that the most successful methods for the laboratory synthesis of heavy elements are fusion-evaporation reactions using heavy-element targets, recoil-separation techniques, and the identification of the nuclei by generic ties to known daughter decays after implantation into position-sensitive detectors [13-15],... 

For the synthesis of superheavy nuclei by complete fusion, larger projectiles with at least twice as many protons and neutrons are required. It soon became obvious that in such reactions the deficit in the yields is even larger than can be explained by post-fusion losses. This problem stimulated systematic studies of heavy-ion reactions all the way down from the first touch of two interacting nuclei until final fusion. New types of reactions -... 

The 48Ca+248Cm system has recently been reinvestigated at Dubna [103], now with positive evidence for the formation of 292116 (see Ch. 1). The half-lives in the postulated decay chain - milliseconds to seconds - fall into the region covered in Figure 11. But the production cross section is two orders of magnitude below the level reached in the previous studies. If these results can further be substantiated, they would give a hint why so many attempts to make superheavy elements by complete fusion failed. Over the years, the question was Is production the problem or is it survival - nuclear reaction or nuclear stability Are the cross sections too low or the half-lives too short These recent results would point to the production as the key problem. 

The clear point, also called the clear melting point, complete melting point, complete fusion point or capillary melting point, is the temperature at which a sample of fat becomes visibly completely clear, indicating the disappearance of all traces of solid fat (Rossell, 1986 Stauffer, 1996). Its measurement is specified by the American Oil Chemists Society (AOCS) Official Method Cc 1-25 (Firestone, 1998). Samples of the tempered fat contained in at least three vertical glass capillary tubes, sealed at their lower ends, are attached to a vertical mercury-in-glass thermometer such that their lower ends are level with the lower end of the thermometer s bulb. This assembly is immersed in a water bath and heated, and the... 

Elhamdani A, Azizi F, Artalejo CR. 2006. Double patch clamp reveals that transient fusion (kiss-and-run) is a major mechanism of secretion in calf adrenal chromaffin cells High calcium shifts the mechanism from kiss-and-run to complete fusion. J Neurosci 26 3030-3036. 

Ciment Fondu is normally made by complete fusion of limestone and bauxite at 1450-1600 C. In order to produce a cement with the desired rapid-hardening properties, both raw materials must be low in SiO,. The molten clinker is tapped off continuously from the furnace, solidifies and is typically crushed and ground to a fineness of about. 00 m- kg . Some iron is reduced to Fe . The colour of cements produced from bauxite can vary from yellow brown to black, but is commonly greyish black. White calcium aluminate cements are usually made by sintering calcined alumina with quicklime (calcium oxide) or high-purity limestone. 

Tiemann (T8) studied the dissolution of silica from a siliceous iron ore by sintering the ore with sodium carbonate followed by leaching the sodium silicate with water. The reaction rates were found to be low after sintering for 4 hr at 1450°F. The residual concentrate was analyzed to be 56% iron, corresponding to 88% dissolution of the silica. Partial to complete fusion resulted when the temperature was increased. 

Complete Fusion of a Hydrate and the Existence of Tioo Saturated Solutions at the same Temperature. 

The distinction between the relations for equilibrium in this case and that previously described, and consequently also the special interest of the phenomena, lies in the noteworthy possibilities attending complete fusion. This has already been pointed out in the case of calcium chloride. 

Cadmium Tungstates.—The anhydrous normal salt, CdWO, remains as colourless crystals when a mixture containing sodium tungstate (4 parts), sodium chloride (16 parts), and cadmium cliloride (11 parts) is heated to complete fusion and allowed to cool. The hydrate, CdW04.2H20, is formed by double decomposition. ... 

Straight tail and complete / fusion of the median fins... 

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