Showing papers on "Liquid paraffin published in 1974"

Development of hamster eggs fertilized in vitro or in vivo

Abstract: Although many workers have fertilized hamster eggs in vitro since the technique was first described by Yanagimachi & Chang (1963), there is only one reported attempt to obtain further development of these eggs in culture (Yanagimachi & Chang, 1964). In this instance, development ceased at the two-cell stage. The present study examines the development in culture of hamster eggs fertilized in vitro and after transfer to recipient foster mothers. Immature female hamsters (5 to 6 weeks old and 60 to 80 g in weight) were induced to superovulate with intraperitoneal injections of 25 i.u. PMSG and HCG given 48 to 56 hr apart. Following removal of the oviducts 15 to 17 hr after the injection of HCG, they were blotted on sterile filter paper to remove excess blood and immersed in liquid paraffin contained in a Petri dish (35 mm in diameter, Falcon Plastics). The eggs and surrounding cumulus cells were released by rupturing the ampullae and the oviducts were discarded. The culture medium used was a modified Tyrode's solution containing 112\m=.\40 mm-NaCl, 2\m=.\20 mm-KCl, 1\m=.\48 mm-CaCl2, 0\m=.\41 mm-MgCl2, 0\m=.\29 mm-NaH2PO4, 4\m=.\56 mm-glucose, 36\m=.\08 NaHCO3, 0\m=.\10 mm-sodium pyruvate, 9 mg bovine

Development of the penetration activity of mouse epididymal spermatozoa in vivo and in vitro.

Abstract: The results of a study of the penetration activity of mouse epididymal spermatozoa are described. Experiments were carried out with adult female and male F9 hybrids aged 8 to 18 weeks. Individual segments of the epididymis were successively removed starting with the caput and taking care to avoid contamination by spermatozoa from the more distal segments. The segments were immediately placed in 50 mcl culture medium in a watch-glass under a layer of liquid paraffin. The spermatozoa were released into the medium by gentle pressure on the tissue with dissecting needles. Superovulation was induced with 8 to 10 IU PMSG administered in 2 doses separated by a 12-hour interval. An injection of 25 IU HCG was given 45-50 hours after the first dose. After laparotomy inseminations were carried out by introducing 10 to 15 mcl sperm suspension into both uterine horns. The females were killed 6 to 6 1/2 hours after insemination and the ova were isolated mounted and fixed. Fertilization was effected in vitro by the method employed by Pavlok and McLaren. After incubation the material was fixed stained and evaluated. In general irrespective of the fertilization method this study confirmed the findings in other mammalian species that the fertility of epididymal spermatozoa diminishes progressively from the distal to the proximal segments of the epididymis.

Crosslinked poly(acryloylmorpholines) as matrices for gel permeation chromatography

Abstract: Crosslinked poly(acryloylmorpholines) have been prepared in bead form by suspension polymerization of N-acryloylmorpholine and N,N′-methylenediacrylamide, respective molar ratios 10/1, in aqueous solution dispersed in liquid paraffin. The swelling properties of beads of two porosities, designated Enzacryl Gel K1 and Enzacryl Gel K2, were measured in a range of common solvents. Gels derived by swelling in both chloroform and tetrahydrofuran were evaluated as column packings for gel permeation chromatography. For Enzacryl Gel K1 and polystyrene solutes, molecular weight exclusion limits of approximately 4 × 103 and 6 × 102 were observed in chloroform and tetrahydrofuran, respectively. In the case of Enzacryl Gel K2, the corresponding exclusion limits were 104 and 5 × 103. Molecular weight fractionation ranges for both polystyrenes and polyethylene glycols are discussed in terms of gel structure.

Micro-encapsulating method

Abstract: The micro-capsules are formed by providing the coating of capsulating agents comprising acetate sulfate of polyglycosides on the core substances. Aqueous solutions of the salt of cellulose acetate sulfate, starch acetate sulfate or dextran acetate sulfate are used as the said acetate sulfate of polyglycosides and the oily substances such as alkyl biphenyl, liquid paraffin, fat and higher alcohol, and pulverulent substances such as active carbon and yeast are used as the core substances. According to the method of present invention, the core substances are added to aqueous solutions of the said polyglycosides to be emulsified and dispersed therein, and then aqueous solutions of polycations are added there to cause insoluble complex comprising the said polyglycosides and polycations, and as resulting the core substances are coated by insoluble complex. Thereafter the said insoluble complex is stiffened by stiffening reagents or being dispersed in aqueous solutions of polyvinyl alcohol, thus producing stable micro-capsules.

Studies of Solubilized Micellar Solutions III. The Viscosity of Solutions Formed with Nonionic Surfactants

Abstract: Viscosity studies have been carried out on a series of oil/water solubilized micellar solutions (so-called “microemulsions”) of liquid paraffin, glycerol, water and blends of Tween 60 and Span 80. The variation of relative viscosity, ηrel, with volume fraction, φ, of the micelles conformed to η rel = exp [ao/(1 - ko)] , where a is a constant and k is the hydrodynamic interaction coefficient. The value of k was found to be independent of micellar diameter over the range 13.3 to 48.6 nm. Decrease in the surfactant/glycerol molar ratio of the solution from 0.231 to 0.028 produced a linear decrease in k from 1.10 to 0.62. For φ ⩽ 0.15, an exponential relationship existed between ηre1 and the surfactant concentration. The effect of the surfactant concentration on the viscosity has been discussed in terms of the interaction between the polyoxyethylene chains at the surface of the micelles. Allowance for the hydration of the polyoxyethylene chain, reduced the value of a towards the theoretical value of 2.5 for solid spheres. Increase of the Tween/Span molar ratio from 1.0 to 1.6 had no significant effect on the values of a or k.

Flow Instabilities in a Capillary Rheometer for an Elastic Polymer Solution

Abstract: A modified capillary rheometer and a motion‐picture camera are used to simultaneously record the pressure at the inlet to the tube, the flow rate through the tube, and the flow patterns in the barrel prior to the entry to the tube. Measured flow curves, employing tubes in the range 14.7⩽L/D⩽36.7 for a medicinal grade liquid paraffin in the range 200⩽γ⩽4000 sec−1 and a highly elastic solution of Separan AP 30 in the range 100⩽γ⩽1500 sec−1, agreed well with the data obtained using a Haake Rotovisco cup and bob viscometer. Motion pictures of the flow patterns in the barrel for the Separan solution showed that the stable converging flow field at low flow rates developed a spiraling instability whose intensity increased with increasing flow rates until a complete breakdown of the flow field occurred at high flow rates prior to a second stage stability. Representative flow patterns in the range 40⩽4Q/ΠR3⩽5154 sec−1 are presented for L/D=36.7 which show the behavior over the entire spectrum of shear rates includ...

Fluorescence Depolarization Study of Hydrogen Bonded 1-Anthrol

Abstract: Rotaional depolarization of 1-anthrol fluorescence was studied in liquid paraffin. The molecular volume of 1-anthrol becomes large when it forms a hydrogen bonded complex. The molecular volume of the complex depends on the concentration of acceptor as well as the kind of acceptor. The molecular volume obtained by extrapolation to nil acceptor concentration increases with increasing size of acceptor molecule and is appreciably larger for amines than for ethers. The emitting species in the case of amines is 1-anthrolate ion pair whose strong dipolar nature may cause further interaction with excess amine molecules. It is probable that more than one molecule of amine participate in the rotating unit, leading to a large molecular volume. The rotational relaxation time was evaluated and found to depend on acceptor concentration. Two competitive effects occur by the increase in acceptor concentration, one shortening the relaxation time because of reduction of viscosity, and the other lengthening it because of mo...

Thermoplastic resin composition having high impact and weather resistance

Abstract: A thermoplastic resin composition having excellent resistance to weather and impact comprises a binary graft-copolymer of a rubber component consisting essentially of an ethylene-propylene rubber and an aromatic vinyl compound or a ternary graft-copolymer of a rubber component consisting essentially of an ethylene-propylene rubber, an aromatic vinyl compound and a vinyl cyanide compound; 0.5 to 10% by weight of liquid paraffin; and an antioxidant and/or an ultraviolet absorber.

A method for determining total carbon dioxide in nanolitre volumes of liquid

Abstract: In the method of Conway (1962) the carbon dioxide is volatilized from the sample by addition of acid, allowed to diffuse through an air space, and finally trapped in barium hydroxide. Consequent change in the concentration of the barium hydroxide is determined by titration. In the method of Little & Ruston (1970) the same basic principles are followed, but the diffusion occurs through nitrogen and the change in concentration of the barium hydroxide is determined by measuring the change in freezing point. In the present method the carbon dioxide diffuses through liquid paraffin so as to prevent significant diffusion of water vapour. Reduction in the scale of operations allows the barium hydroxide to be transferred directly to the freezing-point apparatus of Ramsay & Brown (1955), without separate sampling. The reduction of scale and the lack of any gas space in the system also enable the liquids to be handled in a single syringe, and ensure that the microdiffusion process is completed in a relatively short time. With this method small volumes of mercury, barium hydroxide, the sample

Repellents, Synthetic Pyrethroids, and Organophosphorus Compounds as Seed Dresangs against Wheat Bulb Fly (Leptohylemyia coarctata (Fall.)

Abstract: SUMMARY New insecticides, some in novel formulations, and insect repellents were tested during 1968–71 as seed dressings to protect winter wheat against attack by wheat bulb fly larvae. Preliminary tests in the laboratory were followed by trials in fields in the Midlands and eastern England. The synthetic pyrethroid insecticide resmethrin at one per cent active ingredient to weight of seed significantly decreased attack by wheat bulb fly in one trial on a sandy clay loam but not on other soils or in other years. The best protection against attack in the field was given by the organophosphorus insecticides C8874 (O,O-diethyl O-2,5-dichloro-4-iodophenyl thiophosphate) and C18244 (O-ethyl-O-(2,5-dichloro-4-iodophenyl) ethyl thiophosphohate). These compounds were more eflective than chlorfenvinphos used as a standard but are unlikely to be developed further in this country. Using polyvinyl acetate formulations, much larger amounts of pyrethroids could be applied to the seeds without decreasing plant emergence, but insect control was not improved. Pre-treatment with liquid paraffin,‘Lutanol M40’(polyvinyl methyl ether) or ‘Polyvis 200’(polybutene) improved adhesion of γ-BHC powder to seed, but effects on plant emergence and on insect control need more testing. A uniform seed to seed distribution of liquid insecticide was obtained by dipping seeds in dilute emulsions of ethion, but these seeds germinated less well than seeds treated with a commercial powder formulation of the same insecticide. Seed dressings of the insect repellents ‘Deet’(N,N-diethyl m-toluamide), MGK 11 (2,3:4,5-bis(2-butylene) tetrahydro-2-furaldehyde) or MGK 874 (2-hydroxyethyl-n-octyl sulphide) failed to protect winter wheat from attack by wheat bulb fly in the field.

Constipation - the secret national problem*

Abstract: ONSTIPATION WAS ONCE uncommon in Britain and is still almost unknown in primitive communities in Africa and Asia; but today over 50 per cent of our population C are troubled by constipation. In fact, compared with most developing countries where an average of two or more large soft motions are passed daily, we could be considered a constipated nation. However, although sufferers will complain about rheumatism, coughs and colds, they feel embarrassed discussing their bowels and to a large extent keep their complaint a secret. It might therefore be correct to think of constipation as the secret national problem and as such it needs more attention than it has previously b-en given. Approximately 40,000 gallons of liquid paraffin are consumed annually (AveryJones and Godding, 1972) with nearly E5m spent on laxatives over and above the 3.5m National Health Service prescriptions (World Medicine, 1970). However, it would be incorrect to claim that the incidence of constipation has greatly increased solely because large quantities of laxatives are now taken. Firstly, constipation must be defined as many Feople use the word incorrectly. Unfortunately, a precise definition is prevented due to the wide variations in normal rhythm of the colon but only if the usual interval becomes irregular or much longer with the motions being hard and passed with difficulty, discomfort, or even pain, can one talk of constipation. The chronic form of faecal arrest is by far the most common and is the type usually denoted by the term ‘constipation’. Hurst (1950) classified functional constipation into: (i) colonic - defective movements of the muscles of the colon. (ii) dyschezia - imperfection of the reflex action of defaecation often due to faulty (iii) deficiency in the bulk of the faeces -due to incorrect diet. bowel habits.

Preparation of Na 2-n-Alkylindole Sulfonates and Their Physico-chemical Properties

Abstract: Three samples of sodium 2-n-alkylindole sulfonate [alkyl : heptyl (R-7 : abridged sign of this compound), undecyl (R-11), pentadecyl (R-15)] were prepared by the following process, _??_-CH3-NH2 RCOCl→-HCl_??_-CH3-NHCOR NaNH2→-H2O_??_-N-H-R H2SO4→-H2O NaO3S+_??_-N-H-Rand identified by elementary analysis, IR and NMR. The physico-chemical properties such as specific gravity, relative viscosity, surface tension, specific electrolytic conductivity. solubilization (dyestuff), sedimentation (CaCO3), emulsification (liquid paraffin) and wetting efficiency (feltcloth) were measured for the aqueous solution of these surfactants.The results obtained were as follows ;1) R-11 decreased the surface tension of water approximately to 4045 dynes per cm.2) R-15 was most excellent amoung many other surfactants in abilities of the solubilization of dyestuff, deflocculation of calcium carbonate and emulsification of liquid paraffin.

A Reaction Product from Butylated Hydroxyanisole and Trimethylamine Oxide

Abstract: The main reaction product obtained when butylated hydroxyanisole (BHA) and tri-methylamine oxide (TMAO) were thermally treated in liquid paraffin under a nitrogen stream at 180 C for 1 hr, was investigated. The crystalline substance obtained by the silica gel chromatography was recrystallized from ethanol and identified as the BHA dimer of biphenyltype, i.e., 2,2′-dihydroxy-5,5′-dimethoxy-3,3′-di-tert-butyl biphenyl, by means of the elementary analysis and the spectroscopic studies.The BHA dimer was found to be inferior to BHA in the antioxidative activity which was compared according to the weight gain method, in either case when lard (at 60°C) and methyl esters of linseed oil (at 30°C) were used as substrates. The dimer showed a synergism with TMAO.

Fluorescence depolarization study of hydrogen bonded 1-anthrol

Abstract: Rotaional depolarization of 1-anthrol fluorescence was studied in liquid paraffin. The molecular volume of 1-anthrol becomes large when it forms a hydrogen bonded complex. The molecular volume of the complex depends on the concentration of acceptor as well as the kind of acceptor. The molecular volume obtained by extrapolation to nil acceptor concentration increases with increasing size of acceptor molecule and is appreciably larger for amines than for ethers. The emitting species in the case of amines is 1-anthrolate ion pair whose strong dipolar nature may cause further interaction with excess amine molecules. It is probable that more than one molecule of amine participate in the rotating unit, leading to a large molecular volume. The rotational relaxation time was evaluated and found to depend on acceptor concentration. Two competitive effects occur by the increase in acceptor concentration, one shortening the relaxation time because of reduction of viscosity, and the other lengthening it because of mo...

Preparation of alkylbenzimidazol-monosulfonates and their physico-chemical properties

Abstract: The following seven compounds were prepared, R-N=C-NH-_??_+SO3Na R : n-pentyl (1) : n-heptyl (2); n-nonyl (3); n-undecyl (4); n-tridecyl (5); n-pentadecyl (6); n-heptadecyl (7), and their physico-chemical properties in aqueous solutions were studied.The results obtained were as follows.1) Surface-active abilities such as reduction of surface tension, emulsification of liquid paraffin, solubilization of Orange OT, deflocculation of calcium carbonate and wet-through to the cotton cloth were observed in the aqueous solutions of sample (3), (4), (5), (6) and (7).2) Sample (6) and (7) appear to be excellent dispersants for various dyes and pigments.