Non-ionic Components Research Articles

Ion-induced splitting in thermal denaturation profiles of F1 nucleohistone

The shape of thermal denaturation profiles for F1 nucleohistone was observed to be a funtion of the ion content of the medium. The temperature derivative profile of denaturation was bimodal at 0.01 M salt but unimodal at low salt. This behavior was not a function of the method of reconstitution, the protein concentration, or the non-ionic components of the solvent. Plots of T m values vs salt concentration indicated that neither of the split peaks was directly related to the single maximum in the derivative profile at low salt. Circular dichroic spectra were not casually related to the profile splitting phenomenon studied by thermal denaturation. The unexpected ion dependence of the denaturation profile is presumed to result from electrostatic factors and the existence of at least two modes of binding of F1 histone to DNA.

Seawater?A test of multicomponent electrolyte solution theories. I. The apparent equivalent volume, expansibility, and compressibility of artificial seawater

The apparent equivalent volume ΦV, expansibility ΦE, and compressibility ΦK of an artificial seawater solution containing10 ionic components (Na+, Mg2+, Ca2+, K+, Sr2+, Cl−, SO 4 2− , HCO 3 − , Br−, and F−) and one nonionic component (H3BO3) has been determined from0 to40°C (in5° intervals) and from0.1 to0.8 m ionic strength at1 atm. The concentration dependence (Iv=volume ionic strength) of the ΦV's, ΦE's, and ΦK's have been examined by using a Masson-type equation, Φ = Φ° +S'I V 1/2, and a Redlich-type equation, Φ = Φ° +SI V 1/2 +BI V, where Φ° is the infinite-dilution value, S′ is the empirical Masson slope, S is the theoretical Debye-Huckel slope, and B is an empirical deviation constant. By using Young's rule, Φ = ∑Eiφ(i), the apparent equivalent volumes, expansibilities, and compressibilities for “sea salt” have been estimated from the ionic and nonionic components making up the mixture. The estimated apparent molal quantities agree very well with the directly measured values providing the concentration terms, S i ′ and Bi, are weighted according to the methods of Wood and Reilly.

A study of the nonionizing component of the cosmic radiation underground

An efficient anticoincidence screen has been designed and operated in the Holborn underground laboratory at a depth of 61 hg cm-2 below the surface. A series of experiments, using different types of counter inside this screen, has been performed to study the properties of the underground nonionizing radiation at energies greater than 5 MeV. It is established that the leakage of muons through the screen was very small. The rate of neutron knock-on events was found to be 1.8 l-1 d-1 for protons of energy greater than 12 MeV. The rate of events due to photons of energy greater than 10 MeV was about 15 l-1 d-1. The origin of these photons is discussed, and it is argued that most of them are due to the bremsstrahlung of electrons knocked on by muons. No evidence is found for any anomalous behaviour of the cosmic radiation underground.

Controlled Foam Laundry Formulations

Heavy duty laundry systems are complex formulations containing a large number of ingredients. They can be formulated to produce a variety of foam profiles. This work has demonstrated that laundry detergent systems, which consist principally of biodegradable nonionic active components, may be formulated to exhibit low and moderate controlled foam profiles under typically American and European working conditions. In addition these formulations demonstrate excellent detergency properties when compared to currently distributed commercial brands.

Controlled foam laundry formulations

AbstractHeavy duty laundry systems are complex formulations containing a large number of ingredients. They can be formulated to produce a variety of foam profiles. This work has demonstrated that laundry detergent systems, which consist principally of biodegradable nonionic active components, may be formulated to exhibit low and moderate controlled foam profiles under typically American and European working conditions. In addition these formulations demonstrate excellent detergency properties when compared to currently distributed commercial brands.

A rapid method for the production control of the non-ionic component in synthetic detergents

A dilute solution of the detergent is slightly acidified and mixed with 20 ml of the cobaltothiocyanate reagent and 20 ml of dichloromethane, the mixture is shaken and allowed to separate.The intensity of the colour of the dichloromethane is measured and the percentage of non-ionic detergent is calculated from straight-line calibration graphs.Graphs are given for varying amounts of ethylene oxide units per molecule and also for varying hydrophobic molecules. In addition, poly(ethylene glycols) of varying molecular weights were checked by this method, together with synthesised fatty acid-poly(ethylene glycol) esters in an attempt to find a relationship between molecular weight and the slope of the graph. It was found that both the hydrophobic and hydrophilic portions of the molecule affect the slope.Anionic detergents interfere in this determination, but a simple method to overcome this interference is given.

Micelle formation in mixtures of nonionic and cationic detergents

AbstractThe effect of a homologous series of polyoxyethylene n‐dodecanols on the critical micelle concentration (cmc) of mixtures with n‐dodecyl trimethyl ammonium bromide (DTAB) and of polyoxyethylene n‐hexadecanols on the cmc of mixtures with n‐hexadecyl trimethyl ammonium bromide (CTAB) has been studied in terms of the composition of the mixtures. The cmc of the nonionic component of the mixed micelles is approximately one hundredth of that of the cationic component. Only a gradual increase in the cmc values of the mixed micelles above the values of the nonionic components was observed in the composition range of 0舑75 mole % or 0舑90 mole %, respectively, of cationic detergent. This is followed by an abrupt transition to the high cmc values of the cationic component. This abrupt transition is considerably reduced by addition of NaBr. It is postulated that in the absence of added electrolyte the degree of ionic repulsion of the cationic component in mixed micelles is markedly decreased as the proportion of nonionic component reaches a threshold range of 25 or 10 mole %, respectively. Swamping of charges reduces ionic repulsion in NaBr solutions and, consequently, the abrupt transition in the cmc vs. composition curves is reduced.

Micelle formation in mixtures of nonionic and anionic detergents

AbstractThis paper describes the effect of a homologous series of polyoxyethylene n‐dodecanols on the critical micelle concentration (CMC) of sodium n‐dodecyl alcohol sulfate as a function of composition of the mixtures and temperature. The CMC of the nonionic component of the mixed micelles is about one‐hundredth of that of the anionic. Only a gradual increase in the CMC values of the mixed micelles above the values of the nonionic components was observed in the composition range of 0舑90 mole % anionic detergent. This is followed by an abrupt transition to the high CMC values of the anionic component. The gradual increase of the CMC values in the range below 90 mole % anionic detergent of n‐dodecanol+ 4 EO exceeds that of the higher homologs containing 7, 23 and 30 ethylene oxide units. It is postulated that the degree of ionic repulsion of the ionic component in mixed micelles is markedly decreased as the proportion of nonionic component reaches a threshold range of 10 mole %. This effect is more pronounced with large ethylene oxide coils operating at the periphery of the micelle core than with short ethylene oxide coils. Thermodynamic data have been included.

Analysis of Phenobarbital Elixir by an Ion Exchange and Nonaqueous Titration Procedure

Phenobarbital elixir is analyzed by passing an aliquot through a strongly basic anion exchange resin. The phenobarbital is eluted from the column with acetic acid in ethanol. After evaporation of the solvent, the residue is dissolved in dimethylformamide and titrated with sodium methoxide in benzene-methanol. Other barbiturate elixirs are assayed similarly. Nonionic components, coloring agents, bases, most salts, and synthetic sweetening agents do not interfere.

Semimicro determination of total fatty acids and unsaponifiable matter

AbstractA semimicro method for determining both total fatty acids and unsaponifiable matter in fats, fatty acids, and soap is presented. The procedure involves saponification and recovery of the total fatty acids (which includes the unsaponifiables), removal of the fatty acids with anion exchange resins, and determination of the unsaponifiable matter by weight.The total fatty acid method was evaluated on seven samples and showed a standard deviation from the mean of 0.21%. The unsaponifiable matter determination gives good reproducibility with a standard deviation from the mean of 0.06%. Since this ion exchange is a direct determination of the nonionic components, the results obtained from it should be more accurate and more nearly the true values than the macro extraction method which is empirical.

Diffusion in binary mixtures

The effect on the ordinary coefficient of diffusion of the mobilities of two interdiffusing, non-ionic components is evaluated by a straightforward application of the equations of irreversible thermodynamics along the lines suggested by De Groot [1]. The form of the resultant equations for the diffusion coefficient indicates that this approach does not agree with experiment so well as that of considering the effect of the different mobilities according to the equations proposed by Darken [2] and others. The analysis given in the text indicates that a binary diffusion coefficient is best calculated from the measured rates of diffusion of radio-active tracers by the equations of Darken [2].

On the penetrating non-ionizing component of cosmic rays

Investigations into the penetrating non-ionizing component of cosmic rays were carried out with an apparatus similar to that used by Jánossy and Rochester (1943), and the results of the former experiments were substantially confirmed and extended. The collision mean free path for the non-ionizing rays, which must be assumed to consist mainly of neutrons, was found to be 270±28 g/cm 2 in lead. This value is significantly greater than the mean value found for the primaries of penetrating showers. Problems concerning the reliability of the experimental method used are discussed.

On the penetrating non-ionizing component of cosmic rays

Investigations into the penetrating non-ionizing component of cosmic rays were carried out with an apparatus similar to that used by Jánossy and Rochester (1943), and the results of the former experiments were substantially confirmed and extended. The collision mean free path for the non-ionizing rays, which must be assumed to consist mainly of neutrons, was found to be 270±28 g/cm 2 in lead. This value is significantly greater than the mean value found for the primaries of penetrating showers. Problems concerning the reliability of the experimental method used are discussed.

A Study of Penetrating Cosmic-Ray Showers in Water

Penetrating showers produced locally by non-ionizing radiation were studied using counter techniques. The collision length in water of the non-ionizing component which is capable of producing penetrating showers was found to be (98\ifmmode\pm\else\textpm\fi{}13) g/${\mathrm{cm}}^{2}$. Comparison of this collision length with that expected from the geometrical cross section seems to indicate that the hydrogen nuclei in water have a rather small cross section for the production of penetrating showers by neutral radiation. Results obtained at two elevations were used to calculate the absorption length in air of the neutral penetrating shower producing component. The absorption length measured, (115\ifmmode\pm\else\textpm\fi{}19) g/${\mathrm{cm}}^{2}$, agrees with that obtained by others for the total penetrating shower producing component.

Observations of the Penetrating Non-Ionizing Component of the Cosmic Radiation

An anticoincidence arrangement of Geiger-Muller counters was used to detect that part of the non-ionizing component which is capable of penetrating 10 cm. of lead. Measurements were made at sea level and at an altitude of 3,560 metres. The mean absorption length of the non-ionizing particles was found to be 170 ± 5 gm. cm-2 in air, 190 ± 35 gm. cm-2 in carbon and 400 ± 25 gm. cm-2 in lead. The secondary particles were strongly absorbed in a few centimetres of lead. Studies were made of the angular distribution of the secondaries and of the production of two or more secondary particles in a single process. Less than 0.5% of the non-ionizing particles were found to be associated with extensive air showers, but about 10% appeared to be produced by ionizing particles interacting in the lead above the apparatus. The angular distribution of the secondary particles produced in carbon was approximately proportional to cos θ. The nature of the non-ionizing particles is discussed and it is concluded that the only known particles which could explain the results are high energy neutrons. On this hypothesis, their energy spectrum and intensity at the two altitudes are calculated.

On the Production of Penetrating Ionizing Particles by the Non-Ionizing Component of Cosmic Radiation

On the Production of Penetrating Ionizing Particles by the Non-Ionizing Component of Cosmic Radiation

The production of penetrating showers

It is shown that about one-third, of the radiation producing penetrating showers is non-ionizing and more penetrating than photons. The total intensity of this non-ionizing radiation (named N-radiation) is found to be about 0-001 % of the full cosmic radiation near sea-level. The N-radiation is possibly the energetic part of the penetrating non-ionizing component of cosmic radiation. It is suggested that this radiation consists of neutrons.

Penetrating non-ionizing cosmic rays

An account is given of experiments proving the existence of a penetrating non-ionizing component of cosmic radiation at sea-level. It is shown that the radiation has a mean range of approximately 10 cm. in lead, and is probably the same as the penetrating non-ionizing radiation discovered by Rossi and Regener in, experiments at 4300 m. above sea-level. An argument is brought forward indicating that the radiation might consist of neutrons.

Connexion between the Penetrating Non-ionizing Component of Cosmic Radiation and Penetrating Showers

IN a recent publication1 we suggested that there is a connexion between penetrating showers produced at sea-level and the penetrating non-ionizing radiation discovered by Rossi and Regener2 on Mt. Evans and by us at sea-level. The present investigation was undertaken with the object of establishing such a connexion. The results show that a considerable fraction of the penetrating showers are produced by a penetrating non-ionizing radiation, but that only a small fraction of this radiation produces penetrating showers.