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In this paper, I wish to argue that an explanation is not a logical structure¸ that it cannot be characterised in syntactic terms, but that it is rather an epistemological structure, and, more specifically, a structure organising conceptual content. I will start from a trivial example and systematically look at the effects of making premises more general or more specific or of reshuffling the same content into another set of premises, thereby exposing the implicit suppositions and consequences of some commonly held views and showing their untenability.

Gel polymer electrolytes based on PMMA and Li salts in PC have been developed for lithium electrochemistry in batteries and electrochromics (for references, see [1]). We have developed a method for their preparation by direct polymerization of PMMA with addition of Li salts in PC, and we have applied this principle to gel electrolytes containing tetraethylamonium salts or sodium salts.

Nuclear fast red [4-amino-1, 3-dihydroxy-anthracene-9, 10-dione-2-sulfonic acid (sodium salt); Fig. 1] is widely used as a dye for nuclei or plasma staining of histological and haematological specimens [1–2]. Its usefulness stems from the specificity of the take up of the dye. Such formulations are used to make aqueous solutions according to standard staining protocols [3].

In his early transplant work Carrel (1908) used Locke’s solution at room temperature to flush organs prior to transplantation and used the same solution chilled to preserve an artery for several days [1]. Locke’s solution was used as a physiologically balanced solution and reference is made to the ‘poisonous effects of the pure sodium salt’. He later worked with Charles Lindbergh (the same Lindbergh who had piloted the Spirit of St. Louis across the Atlantic) and together they studied perfusion preservation of organs at normothermia using large volumes of oxygenated plasma to keep tissues viable for many days, but then did not go on to test their results in a transplant model [2]. Carrel thus pioneered not only organ transplantation but also the techniques of simple cold storage and of machine perfusion which were to reemerge in the 1960s for clinical organ preservation. In his work he quotes Le Gallois (1770–1814) as predicting ‘If one could substitute for the heart a kind of injection … of arterial blood, either natural or artificially made … one would succeed easily in maintaining alive indefinitely any part of the body’. This apparently simple prediction has proved remarkably difficult to achieve in practice.

The mononucleotide 5’AraCMP, a 5’CMP isomer, is a drug commonly employed in the treatment of certain types of cancer. To explain the mechanism of therapeutical action of this drug it is important to study the possible differences in the interaction between 5’AraCMP and 5’GMP, and the complementary Watson-Crick pair 5’CMP-5’GMP. These differences are studied through concentration effects on the infrared, IR, spectra of these mononucleotides (homogeneous systems) and its equimolar mixtures (heterogeneous systems) in 2H2O. Band splitting, changes of band widths, relative absorbances, and frequencies are analyzed.

The photostability of piroxicam sodium (PNa) complexed with β-cyclodextrin (β-CD) was investigated in solution by comparative evaluation of PNa and the 1:1, 1:2, and 2:1 PNa-β-CD complexes and physical mixtures. The order of stability of PNa in the complexes/physical mixtures is reported as the 1:2 complex being the most unstable followed by 2: 1>1: 1 with the uncomplexed PNa being the most stable.

In the past 20 years, cyclodextrin (CD) research has achieved considerable results, as indicated by the seven earlier symposia on CDs, and the new dosage forms prepared with them. Furosemide (F) is slightly soluble in water (10.26 mg/100 g) [1-3]. Different CDs increase the solubility of F to various degrees, depending on their ratios and the methods of preparation. The parameters of the solutions are changed and the inclusion complex formation was analysed.

In order to obtain better abiotic receptors for analytical and kinetic applications, the new capped derivative of cyclomaltoheptaose (CDTH) was synthesized by reaction of 6, 6’-dideoxy-6, 6’-di(S-cysteamine)-α, α’-trehalose with 6A, 6D-dideoxy-6A, 6D-diiodo-cyclo-maltoheptaose. The CDTH-ACS (anthraquinone-2-sulfonic acid sodium salt) system was investigated, by 1H NMR spectroscopy and by i.c.d. (induced circular dicroism), and a deep inclusion of ACS inside the CDTH cavity, with an association constant about six times larger with respect to ACS — β-CD system was found.

Normal coordinate analysis of nucleic acid components is a valuable help for the assignment of the vibrational spectra of these compounds. A big effort has been dedicated to force constants calculations of nucleic acid bases [1, 2] and some nucleotides [3].

Since 1974 the most widely studied water soluble phosphines are those with sulfonated phosphines, the sodium salts of : metasulfophenyl-diphenylphosphine (TPPMS) tri-(metasulfophenyl) phosphine (TPPTS)

Near infrared absorption (NIR) has been known to activate proton transfer in molecular crystals containing hydrogen bonds [1]. In presented experiments, the same process is observed in water solution of L-glutamic and poly-L-glutamic sodium salt in presence of spin probe TEMPO — a free radical.

Disulfiram (DSSD), widely known under the trade name, Antabuse®, is a symmetrical disulfide which can be reduced to two molecules of the thiol (DSH) which, at physiological pH is better than 99% ionized to diethyldithiocarbamate and so referred to in this book. The sodium salt of diethydithiocarbamic acid is available both in an anhydrous form and as a trihydrate. It was earlier given the appellation dithiocarb (West and Sunderman, 1958; Sunderman and Sunderman, 1958; Merck Index, 1968). More recently it has been assigned the International Nonproprietary Name ditiocarb sodium (Merck Index, 1989; USAN, 1990).

An extended set of bisphenolic coordination polymers were synthesized by reaction of a series of bisphenolic chelates with terephthaloyl and isophthaloyl chlorides. Alternately, polymers were obtained by reaction of bisphenolic chelate sodium salts with α,ω- dichloropoly-dimethylsiloxane. The magnetic, conducting, oxygen coordinating abilities and thermal stabilities of the various polymers were established using standard analytical techniques. In general, the polymers were paramagnetic, p-type semiconductors. Thermal stabilities are moderate.

Initial work with calixarenes involved the p-tert-butyl derivative which has a very low water solubility [1]. Substitution at either the ‘upper rim’, R, or the ‘lower rim’, Y, of the calixarene, I, can lead to water-soluble species. These substances are of particular importance with regard to cation complexation [2]. The focus of this chapter is on ‘upper rim’-substituted derivatives of calix[4]arenes.

In 111-oxine labelled platelets are routinely used in our department to monitor kidney grafted patients (1–3). The labelling is performed in non-plasma media which are believed not to affect cell function. However, there is a general agreement that L=ct labelling in plasma may better preserve platelet functionability. Recently Thakur et al have published their experience with a new labelling agent (4); the sodium salt of 2-Mercaptopyridine-N-oxide (Merc) which permits 111-In cell labelling in a plasma medium.

This steroid antibiotic derived from Fusidium coccineum fungus is chemically related to cephalosporin P1. The acid forms colourless crystals which are sparingly soluble in water compared with the sodium salt, sodium fusidate, which is highly water soluble.

Introductory papers by Claude Rovere discussing the CNRS experiment to heat sodium salt particles to 1000°C and by Manfred Becker discussing the “State-of-the-Art” and constraining influences opened the session. Mr. Royere described the experiment schematically and physically as it is currently installed at the “Four Solaire” in Odeillo, France. Results to date include a production run test achieving a 6000 kg/hr rate of particle with the 50 KWt solar powered experiment (a small fraction of the facility power).

The criticism is frequently made that studies of drug toxicity in experimental animals do not necessarily reflect the side-effects of the same drug in man. It is interesting to reflect upon the comments of Virchow last century: ‘Between animal and human medicine, there is no dividing line — nor should there be. The object is different but the experience obtained constitutes the basis of all medicine.’ (R. Virchow, 1821–1902). It is difficult to combat this criticism by direct challenge, since the clinician very rarely has the requisite information concerning the incidence and severity of side-effects in all patients treated: data that can only be obtained with an enormous expenditure or effort.

The aim of treating organic liquids with sodium is to destroy organic compounds containing halogens, especially chlorides, and the separation of the sodium salts formed in the process, in order to be able to recycle and reuse these organic liquids to satisfy environmental regulations formulated for the F.G.R. The destruction of polychlorinated biphenyles (PCB’s), dibenzo-dioxines (PCDD’s) or dibenzo-furanes (PCDF’s) is of particular importance.