Various methods for the production, properties, applications of fire extingaishing agents such as Halon 1301, 1211, 2402, and fluorirated surfactants are revewed and discussed.

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Recent trends of the market and technology in fluoroelastomers are reviewed.
Fluoroelastomers have been increasingly used in a variety of application fields such as chemical, automotive, electric, machinery and energy related industries as the most reliable elastometric material. These expanding applications have concurrently stimulated the technology of fluoroelastomers to develop and improve such elastomers as vinylidene fluoride-hexa fluoropropylene, tetrafluoroethylene-propylene, perfluorinated, fluorosilicone, phosphazene, etc. exhibiting still enhanced heat, chemical, oil, low temperature resistances, through creating new polymer, modifying the composition, or introducing new vulcanization recipe.

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The surface plasma treatments for fluorine-containing materials are summarized. The plasma-solid interactions are divided into two groups : the interaction of fluorocarbon polymers such as polytetrafluoroethylene, poly (vinyl fluoride), and poly (vinylidene fluoride) (PVdF) with plasmas of O₂, He, Ar, etc., and the interaction of hydrocarbon polymers such as polyethylene and polypropylene with plasmas of F₂, CF₄, etc.. Particularly, the fluorination of polymers due to the latter interaction and changes caused in the surface properties are described in detail. A difference in the reactivity of PVdF and ethylene-propylene copolymer (EPDM) with CF₄ and Ar plasmas is clarified using XPS data.

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A great number of analytical techniques have been developed taking advantage of the marked specialities of fluorine compounds. This article surveys the successful applications of fluorine compounds to the designing of analytical reagents, methods, and separation techniques in recent years. Brief comments are also made on their features in terms of the basic properties of fluorine compounds.

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The importance of microbial behavior of halogen-containing compounds, which are hardly decomposed by microorganisms, has been recognized in living systems. Especially, in fluorine chemistry, considerable attention has been focused on the search for chiral synthetic tools for the preparation of fluorinated bioactive molecules. In this review, we wish to outline the possibility of microbial transformation of fluorinated compounds under stereocontrol.

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The fatty acid composition and trans fatty acid content of lipids in biscuits or crackers were determined. The lipids contained greater amounts of saturated or trans fatty acids, but only small amounts of poly unsaturated fatty acide. The lipids were classified into two groups on the basis of fatty acid composition : a highly saturated acid group (total saturated acid≥55%), and a low saturated acid group (total satuated fatty acid 55%). The lipids of the highly unsaturated acid group were found to contain greater amounts of 12 : 0 fatty acid (source assumed to be coconut oil), while those of the low saturated acid group greater amounts of trans acid (possibly from hydrogenated vegetable oil). Roughly estimating, the lipids of biscuits or crackers were found to consist of palm oil and hydrogenated vegetable oil (low saturated acid group).

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The extraction of carotenes from palm oil was examined using a self-prepared adsorbent (alumina : active clay=1 : 4). Prior to the adsorption experiments, crude palm oil was treated with P₂O₅, H₃PO₄, or polyphosphoric acid at 80°C for 1h. Most of the experiments were carried out at 50°C for 1h using 20.0g of a pretreated oil and 13g of the adsorbent. Adsorbed carotenes were released with a 20% (vol) acetic acid heptane solution. Carotene content was determined as β-carotene by spectrophotometry.
Pretreatment with H₃PO₄ or polyphosphoric acid favored carotene adsorption. The washing of crude palm oil with water following pretreatment also improved carotene adsorption. The adsorption of other components was found to take place at the same time as that of the carotenes and only a portion of adsorbed carotenes was released under the present conditions. The highest enrichment ratio and carotene recovery were obtained in the case of the oil pretreated with P₂O₅, the respective values being 11.3 and 34.3%.
The results of experiments at various temperatures indicated the adsorption of carotenes on the present adsorbent to be chemisorptive in nature.

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Glycerolysis reactions of corn oil by Pseudomonas fluorescens lipase were studied batchwise in a small agitated vessel. The sampled reaction mixture was extracted with chloroform and the relative content of triglyceride (TG), 1, 2-diglyceride (1, 2-DG), 1, 3-diglyceride (1, 3-DG), 1-monoglyceride (1-MG), 2-monoglyceride (2-MG) and free fatty acid (FFA) of the condensed chloroform sample was determined using a TLC/FID analyzer. The effects of agitation speed on the initial rate of conversion were examined. Above 350rpm, the rate was maximum and constant. The time course of glycerolysis showed that at the beginning, the content of 1, 2-DG exceeded that of 1, 3-DG, but later, this was reversed. In two isomers of MG, 1-MG was detected almost exclusively, 2-MG being formed very little. The initial rates of conversion and formation of the products were proportional to enzyme concentration. No appreciable glycerolysis took place at very low water concentrations. No FFA was formed below 4% water concentration in glycerol. Above 4%, the initial FFA formation was proportional to water concentration to the 2.7th power. The dependence of the initial rate of conversion on the temperature obeyed the Arrhenius equation, giving 6.13kcal/mol of activation energy.
No variation in equilibrium composition was observed in the range of 1535% of the weight proportion of the oil to the total reaction mixture. The equilibrium composition did not change with variation in enzyme concentration or temperature from 2565°C. The equilibrium composition was significantly influenced by water concentration. Below 4% water in glycerol, no FFA was present in the product mixture. The composition of the product at 3.7% water concentration in glycerol was : 20.1% 1-MG, 0.3% 2-MG, 12.3% 1, 2-DG, 29.5% 1, 3-DG, 0.0% FFA, and 37.3% unreacted TG.

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The continuous glycerolysis of olive oil by Pseudomonas fluorescens lipase was performed at 40°C in a microporous hydrophobic membrane bioreactor previously developed by the authors. Two kinds of flat membranes, one made of polypropylene and the other made of poly (tetrafluoroethylene) (Teflon), were used. The olive oil was fed into the fat compartment on one side of the membrane and the product was obtained from the outlet in a single phase. The glycerol containing small amounts of water and enzyme was fed in to the opposite side of the membrane in the bioreactor and recycled to the glycerol reservoir. After 920 hours of a transient state, steady states were attained. The enzyme concentration in the glycerol phase did not affect the composition of the outlet product. Teflon membrane gave a somewhat higher conversion than the polypropylene membrane. The conversion increased with a decrease in flow rate, approaching the one at chemical equilibrium. The conversion was highly restricted at lower water concentrations. At water concentrations higher than 4%, free fatty acid was produced. The half life of the enzyme during the continuous reaction was about 3 weeks.

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The chemical modification (N-acylation) of bovine serum albumin (BSA) by N-acyloxysuccinimides (1) (CN=28) was studied kinetically at 25°C (7.0≤pH ≤9.0). N-Acylation was competitive with the decomposition of (1) and the rate of which is expressed as V= (k₁, _d+k₂ [BSA]) [(1), ] where K₁, _d is the first order rate constant for the decomposition of (1) and k₂ is the second order rate constant for the N-acylation of BSA by (1).
The reactivity of (1) with BSA was in the order of CN=2>CN=3>CN=4<CN=5<CN=6<CN=7<CN=8. The addition of sodium carboxylates surpressed the N-acylation of BSA in the order of C₇H₁₅COONa>C₅H₁₁COONa>C₃H₇COONa. This order corresponded tentatively to the fluorescence difference spectra of BSA by the addition of sodium carboxylate. These findings indicate hydrophobic interaction between BSA and alkyl group in (1) to possibly accelerate the N-acylation of BSA. This was supported by the chemical modification of BSA in a preparative scale. The rate ratio, k₂/k₁, _d, maximized at about pH 8.0 and increased with increasing CN in (1) for CN≥4 and 10^-3k₂/k₁, _d larger than unity.
From the above observations, (1) is concluded to be applicable as an N-acyl reagent, to the chemical modification of Lys residues in proteins.

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The reaction of 1, 2-epithiooctane with t-butylamine in a glass ampoule gave 1- (N-t-butylamino) -2-octanethiol (1) and 1- (N-t-butylaminomethyl) heptyl 2-mercaptooctyl sulfide (2). The ratio of (1) / [(1) + (2)] was high at the initial stage of the reaction, and decreased as the reaction proceeded. Excess t-butylamine caused no significant increase in the total yield. The addition of a small amount of alcohol promoted the reaction in a similar manner to the reaction of 1, 2-epithiooctane with secondary amine. (1) was concluded to be produced by a nucleophilic attack of t-butylamine on the terminal methylene of the ring of 1, 2-epithiooctane, and (2) to result from the reaction of the mercapto group of (1) with 1, 2-epithiooctane.

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The Triglyceride (TG) Committee of the Japan Oil Chemists' Society (JOCS) participated in a collaborative study by the International Union of Pure and Applied Chemistry (IUPAC) for TG analysis by gas-liquid chromatography (GLC) using six samples provided by IUPAC : lard, butter fat, soybean oil, hydrogenated soybean oil, groundnut oil, and anhydrated butter fat. This study, based on the total acyl carbon number, was conducted by fifteen organizations of nine countries. A summary of the results obtained will be reported in this journal at this issue. Our committee determined the major TG molecular species in the samples using field desorption mass spectrometry (FD-MS), high performance liquid chromatography (HPLC) and the GLC of the collaborative study. The major molecular species in TG of lard, groundnut oil, and soybean oil were found to be palmito-oleo-linolein, mono-oleo-di-linolein and/or mono-palmito-di-linolein and mono-oleo-di-linolein, respectively.
GLC, FD-MS, and HPLC analyses were found to provide significant information by which the major molecular species of TG in naturally occuring fats and oils could be estimated.

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A simple rapid method for determination of nickel in hydrogenated oil was investigated. Extraction of nickel with hydrochloric acid instead of asking prior to the atomic absorption spectro-photometry was found suitable for routine analyses. A trace amount of nickel in hydrogenated oil could be sufficiently recovered by the following procedure : 20g of the oil were dissolved in 50100ml of carbon tetrachloride and then extracted three times with 50ml of 0.5N hydrochloric acid solution. Analytical results for several hydrognated oils obtained by this method agreed well with those by the JOCS method. This method may possibly be applicable to margarine and shortening present in various emulsifiers.

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Hardened palm oil was found to deteriorate with an abnormal increase in acid value (AV) during storage. Therefore, a study was carried out to determine the causes of this and how to prevent it.
1) The increase in AV of hardened palm oil depended on the degree of hardening and storage temperature. The increase was marked when the oil had an iodine value of 1030 and contained more elaidic acid than oleic acid. Also it was more marked during storage at 25°C than that at 15°C or 37°C.
2) The addition of lipophilic sucrose fatty acid ester (SE-1) or soybean lecithin was effective for the most part in preventing deterioration. However, no effects were observed by the addition of monoglyceride or polyoxyethylene sorbitan fatty acid ester.
3) Hardened palm oil without emulsifiers storage at 25°C showed a rough crystal surface with a pile of irregular crystal size under scanning electron microscope. The surface of palm oil samples emulsified with SE-1 or soybean lecithin was smooth.

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