Weight, regulation

Other than fuel, the largest volume appHcation for hexane is in extraction of oil from seeds, eg, soybeans, cottonseed, safflower seed, peanuts, rapeseed, etc. Hexane has been found ideal for these appHcations because of its high solvency for oil, low boiling point, and low cost. Its narrow boiling range minimises losses, and its low benzene content minimises toxicity. These same properties also make hexane a desirable solvent and reaction medium in the manufacture of polyolefins, synthetic mbbers, and some pharmaceuticals. The solvent serves as catalyst carrier and, in some systems, assists in molecular weight regulation by precipitation of the polymer as it reaches a certain molecular size. However, most solution polymerization processes are fairly old it is likely that those processes will be replaced by more efficient nonsolvent processes in time. 

Acetic acid formulations frequently contain acetic acid additions as molecular weight regulators... 

Essentially, at a fixed monomer feed composition and temperature such a dependence is of universal character irrespective of the way of molecular weight regulation, which could be performed by changing the concentration either of the initiator or the transfer agent. Just on this universal curve the points fall which characterize the composition and molecular weight of the fractions isolated from copolymers synthesized under different contents of initiator and transfer agent. 

In early studies of the molecular weight-regulating efficiency of various olefins in the metathesis polymerization of cyclopentene, the results of... 

Acyclic olefins act as chain scission agents in cycloolefin polymerization hence, they are employed as molecular weight regulators. Equations (48)-(50) illustrate the sequence by which chain scission is achieved ... 

Non-mast cell histamine is found in several tissues, including the brain, where it functions as a neurotransmitter. Strong evidence implicates endogenous neurotransmitter histamine in many brain functions such as neuroendocrine control, cardiovascular regulation, thermal and body weight regulation, and sleep and arousal (see Chapters 21 and 37). 

Inui, A. (1999) Feeding and body-weight regulation by hypothalamic neuropeptides—mediation of the actions of leptin. Trends Neurosci. 22, 62-67. 

Detailed review of the role of leptin in body-weight regulation, the control of food intake, and the roles of white and brown adipose tissues in energy expenditure. 

Korner, J. Aronne, L.J. (2003) The emerging science of body weight regulation and its impact on obesity treatment. J. Clin. Invest. Ill, 565-570. 

Emulsion Polymerization. Poly(vinyl acetate)-based emulsion polymers are produced by the polymerization of an emulsified monomer through free-radicals generated by an initiator system. An emulsion recipe, in general. contains monomer, water, protective colloid or surfactant, initiator, buffer, and perhaps a molecular weight regulator. 

Seefeld MS, Keesey RE, Peterson RE. 1984b. Body weight regulation in rats treated with... 

Fantino M, Cabanac M (1980) Body weight regulation with a proportional hoarding response. Physiol Behav 24 939-942... 

Fantino M, Boucher H, Fafon F, Mathiot P (1988) Dexfenfluramine and body weight regulation experimental study... 

Butadiene-Styrene Rubber occurs as a synthetic liquid latex or solid rubber produced by the emulsion polymerization of butadiene and styrene, using fatty acid soaps as emulsifiers, and a suitable catalyst, molecular weight regulator (if required), and shortstop. It also occurs as a solid rubber produced by the solution copolymerization of butadiene and styrene in a hexane solution, using butyl lithium as a catalyst. Solvents and volatiles are removed by processing with hot water or by drum drying. 

Maldonado-Irizarry CS, Kelley AE (1995) Excitotoxic lesions of the core and shell subregions of the nucleus accumbens differentially disrupt body weight regulation and motor activity in rat. Brain Res Bull 38(6) 551 559. 

Baptista T, Lacruz A, de Mendoza S, Guillen MM, Burguera JL, de Burguera M, Hernandez L. Endocrine effects of lithium carbonate in healthy premenopausal women relationship with body weight regulation. Prog Neuropsychopharmacol Biol Psychiatry 2000 24(1) 1-16. 

Table 16. Isotactic polypropene waxes prepared by [Me2Si(2Me-4tBu-Cp)2]ZrCl2/MAO (I), [Me2Si(IndH )2]ZrCl2/MAO (II) compared to waxes produced by conventional catalysts via molecular weight regulation by hydrogen (III) or visbreaking of PP random copolymers (IV) or homopolymers (V) [155]...

Weight regulation is normally a very precise process. Ignoring short-term fluctuations (which are mostly gain and loss of water), body weight stays remarkably constant. Weight regulation... 

There is a major negative feedback loop involving the hypothalamus, corticotrophin-releasing hormone, corticotropin (=ACTH) secreted by the pituitary and corticosteroids from the adrenal cortex, which dampen pro-inflammatory cytokine production. This loop normally acts to stabilise immune system activity, but it also has spillover effects on appetite and weight regulation. 

M. A. Pelleymounter, et al Effects of the obese gene product on body weight regulation in oblob mice. Science, 269, 540-543, 1995. Also J. L. Halaas, et al. Weight-reducing effects of the plasma protein encoded by the obese gene. Science, 269, 543-546, 1995. 

Molecular weight regulator. tert-Dodecyl mercaptan (t-DlBK/), purpled py double distillation in vacuum used in polymerization experiments acc[Pg.64]

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