bluuebunny/crossref_metadata_2025 huggingface dataset:
Similar changes of hypothalamic feeding‐regulating peptides mRNAs and plasma leptin levels in PTHrP‐, LIF‐secreting tumors‐induced cachectic rats and adjuvant arthritic rats
Authors: Suzuki Hitoshi , Hashimoto Hirofumi , Kawasaki Makoto , Watanabe Miho , Otsubo Hiroki , Ishikura Toru , Fujihara Hiroaki , Ohnishi Hideo , Onuma Etsuro , Yamada‐Okabe Hisafumi , Takuwa Yoh , Ogata Etsuro , Nakamura Toshitaka , Ueta Yoichi
Published: July 2010

Parathyroid hormone‐related protein (PTHrP) is a causative factor of humoral hypercalcemia in malignancy. However, it is difficult to explain the mechanism of anorexia/cachexia with PTHrP secretion in detail. Previously, we demonstrated that the expressions of orexigenic peptides increased and anorexigenic peptides decreased under cachectic conditions in rats carrying tumors secreting PTHrP. In this study, we investigated whether such changes in the expression of hypothalamic feeding‐regulating peptides can be solely attributed to PTHrP or are a general response under cachectic conditions. Cachectic syndromes were induced in rats by: (i) inoculation of human lung cancer LC‐6 cells that secreted PTHrP, (ii) inoculation of human melanoma SEKI cells that secrete not PTHrP but LIF1, (iii) injection of heat‐killed Mycobacterium leading to arthritis (AA) and (iv) oral administration of a high dose of 1α,25(OH)2D3 that resulted in hypercalcemia. The LC‐6‐bearing rats and AA rats were treated with or without anti‐PTHrP antibody and indomethacin, respectively, and the expression of the hypothalamic feeding‐regulating peptide mRNAs were examined by in situ hybridization histochemistry. The orexigenic peptide mRNAs, such as neuropeptide Y and agouti‐related protein, were significantly increased, and that of anorexigenic peptide mRNAs, such as proopiomelanocortin, cocaine‐ and amphetamine‐regulated transcript and corticotropin‐releasing hormone were significantly decreased when they developed cachectic syndromes and AA. A high dose of 1α,25(OH)2D3 caused hypercalcemia and body weight loss but did not affect the expression of hypothalamic feeding‐regulating peptide mRNAs. The expressions of the hypothalamic feeding‐regulating peptides change commonly in different chronic cachectic models without relating to serum calcium levels.
Estimating the returns to schooling: a likelihood approach based on normal mixtures
Authors: Dagsvik John K. , HÆgeland TorbjØrn , Raknerud Arvid
Published: July 2010

In this paper we develop likelihood‐based methods for statistical inference in a joint system of equations for the choice of length of schooling and earnings. The model for schooling choice is assumed to be an ordered probit model, whereas the earnings equation contains variables that are flexible transformations of schooling and experience, with corresponding coefficients that are allowed to be heterogeneous across individuals. Under the assumption that the distribution of the random terms of the model can be expressed as a finite mixture of multinormal distributions, we show that the joint probability distribution for schooling and earnings can be expressed on closed form. In an application of our method on Norwegian data, we find that the mixed Gaussian model offers a substantial improvement in fit to the (heavy‐tailed) empirical distribution of log‐earnings compared to a multinormal benchmark model. Copyright © 2010 John Wiley & Sons, Ltd.
Estimation of sample selection models with spatial dependence
Authors: Flores‐Lagunes Alfonso , Schnier Kurt Erik
Published: July 2010

We consider the estimation of a sample selection model that exhibits spatial autoregressive errors (SAE). Our methodology is motivated by a two‐step strategy where in the first step we estimate a spatial probit model and in the second step (outcome equation) we include an estimated inverse Mills ratio (IMR) as a regressor to control for selection bias. Since the appropriate IMR under SAE depends on a parameter from the second step, both steps are jointly estimated employing the generalized method of moments. We explore the finite sample properties of the estimator using simulations and provide an empirical illustration. Copyright © 2010 John Wiley & Sons, Ltd.
Bone strength measured by peripheral quantitative computed tomography and the risk of nonvertebral fractures: The osteoporotic fractures in men (MrOS) study
Authors: Sheu Yahtyng , Zmuda Joseph M , Boudreau Robert M , Petit Moira A , Ensrud Kristine E , Bauer Douglas C , Gordon Christopher L , Orwoll Eric S , Cauley Jane A ,   for the Osteoporotic Fractures in Men (MrOS) Research Group
Published: July 2010

Many fractures occur in individuals without osteoporosis defined by areal bone mineral density (aBMD). Inclusion of other aspects of skeletal strength may be useful in identifying at-risk subjects. We used surrogate measures of bone strength at the radius and tibia measured by peripheral quantitative computed tomography (pQCT) to evaluate their relationships with nonvertebral fracture risk. Femoral neck (FN) aBMD, measured by dual-energy X-ray absorptiometry (DXA), also was included. The study population consisted of 1143 white men aged 69+ years with pQCT measures at the radius and tibia from the Minneapolis and Pittsburgh centers of the Osteoporotic Fractures in Men (MrOS) study. Principal-components analysis and Cox proportional-hazards modeling were used to identify 21 of 58 pQCT variables with a major contribution to nonvertebral incident fractures. After a mean 2.9 years of follow-up, 39 fractures occurred. Men without incident fractures had significantly greater bone mineral content, cross-sectional area, and indices of bone strength than those with fractures by pQCT. Every SD decrease in the 18 of 21 pQCT parameters was significantly associated with increased fracture risk (hazard ration ranged from 1.4 to 2.2) independent of age, study site, body mass index (BMI), and FN aBMD. Using area under the receiver operation characteristics curve (AUC), the combination of FN aBMD and three radius strength parameters individually increased fracture prediction over FN aBMD alone (AUC increased from 0.73 to 0.80). Peripheral bone strength measures are associated with fracture risk and may improve our ability to identify older men at high risk of fracture. © 2011 American Society for Bone and Mineral Research.
From acetylene complexes to vinylidene structures: The GeC2H2 system
Authors: Hao Qiang , Simmonett Andrew C. , Yamaguchi Yukio , Fang De‐Cai , Schaefer Henry F.
Published: July 2010

The expansion of germanium chemistry in recent years has been rapid. In anticipation of new experiments, a systematic theoretical investigation of the eight low lying electronic singlet GeC2H2 stationary points is carried out. This research used ab initio self‐consistent‐field (SCF), coupled cluster (CC) with single and double excitations (CCSD), and CCSD with perturbative triple excitations [CCSD(T)] levels of theory and a variety of correlation–consistent polarized valence cc‐pVXZ and cc‐pVXZ‐DK (Douglas‐Kroll) (where X = D, T, and Q) basis sets. At all levels of theory used in this study, the global minimum of the GeC2H2 potential energy surface (PES) is confirmed to be 1‐germacyclopropenylidene (Ge‐1S). Among the eight singlet stationary points, seven structures are found to be local minima and one structure (Ge‐6S) to be a second‐order saddle point. For the seven singlet minima, the energy ordering and energy differences (in kcal mol−1, with the zero‐point vibrational energy corrected values in parentheses) at the cc‐pVQZ‐DK (Douglas‐Kroll) CCSD(T) level of theory are predicted to be 1‐germacyclopropenylidene (Ge‐1S) [0.0 (0.0)] < vinylidenegermylene (Ge‐3S) [13.9 (13.5)] < ethynylgermylene (Ge‐2S) [17.9 (14.8)] < Ge‐7S [37.4 (33.9)] < syn‐3‐germapropenediylidene (Ge‐8S) [41.2 (37.9)] < germavinylidenecarbene (Ge‐5S) [66.6 (61.6)] < nonplanar germacyclopropyne (Ge‐4S) [67.8 (63.3)]. These seven isomers are all well below the dissociation limit to Ge (3P) + C2H2(
$\widetilde{\rm X}$
1Σ). This system seems particularly well poised for matrix isolation infrared (IR) experiments. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Effect of the biomass in the modelling and simulation of the biofiltration of hydrogen sulphide: simulation and experimental validation
Authors: Silva Javier , Morales Marjorie , Cáceres Manuel , Martín Ricardo San , Gentina Juan Carlos , Aroca Germán
Published: July 2010

BACKGROUND: Several models have been developed to simulate the decay of pollutants concentration along the biofilter and to predict its performance. Despite the evidence, it is common that most models ignore the effect of variable biomass along the biofilter. An equation that represents the variable amount of active biomass along the column was included in the modelling of a biotrickling filter; it was obtained by measuring the active biomass at different heights. Validation of the model was carried out using experimental data obtained at different H2S loads.

RESULTS: The simulation considering the expression for variable active biomass along the column shows better correlation with experimental results. With the diffusion coefficient that shows the best fit with the experimental results; 1.35 × 10−9 m2 s−1, the value of the Thiele module is 2 × 10−3, indicating that biooxidation of H2S is controlled by mass transfer.

CONCLUSIONS: A better correlation between experimental results and model prediction is obtained when the expression for variable active biomass along the column is considered in the modelling. Copyright © 2010 Society of Chemical Industry
Selective photocatalytic degradation of azodyes in NiO/Ag3VO4 suspension
Authors: Hu Xuexiang , Hu Chun
Published: July 2010

BACKGROUND: This work deals with the development of an active heterogeneous catalyst for selective organic synthesis under both visible light and UV irradiation to utilize efficiently solar light. Very few studies have been reported on the selective photooxidation performance of multimetal oxide materials under visible light irradiation. The photocatalytic degradation of azodyes was investigated systematically in aqueous NiO/Ag3VO4 dispersion under visible light irradiation.

RESULTS: The catalyst NiO/Ag3VO4 showed high activity and selectivity for the photodegradation of the nonbiodegradable azodyes acid red B, reactive brilliant red X‐3B, and acid orange 7. From total organic carbon (TOC), Fourier transform infrared spectroscopy (FTIR), and gas chromatography/mass spectroscopy analyses, the tested azodyes were selectively oxidized into aromatic and aliphatic acids without any decrease of TOC. The high photooxidation selectivity also applied to UV light irradiation. Electron spin resonance and radical scavenger studies suggest that the anionic superoxide radical O2−• was the predominant active species in the photocatalytic reaction.

CONCLUSION: The selectivity of NiO/Ag3VO4 for the oxidation of azodyes was not affected by the energy of light (UV and visible light). This approach allows effective controlled oxidation but avoids undesirable mineralization into CO2 and H2O. Copyright © 2010 Society of Chemical Industry
The extrusion and properties of ‘Saran’ monofilaments
Authors: Jack J. , Horsley R. A.
Published: July 2010

The manufacturing details of the production of ‘Saran’ (vinylidene chloride copolymer) monofilaments are given. The changes in molecular structure occurring during each stage of the production are analysed, and the effect of these on the properties of the final monofilament are discussed with a view to obtaining the conditions for producing monofilaments with optimum properties.
Determination of tin‐iron alloy coating in electro‐tinplate
Authors: Thwaites C. J. , Hoare W. E.
Published: July 2010

In electrolytic tinplate the tin‐iron alloy layer, formed during the flow‐brightening operation, may range in thickness from approximately 1·5 to 8 μin. Refined methods of determination are thus necessary. Four procedures have been studied and compared. Gravimetric methods, involving determination of the free‐tin (unalloyed) and alloy layers either separately, or simultaneously as the total coating, appear to be sufficiently accurate and trustworthy provided that a large enough sample‐area is available. A ‘coulometer’ method, involving measurement of the quantity of electricity required to dissolve the coating anodically in dilute hydrochloric acid, was found to be most suitable for rapid routine determinations on relatively small specimens for which gravimetric or volumetric methods would be inappropriate.

It has been confirmed, by chemical and X‐ray examinations, that the tin‐iron alloy layer in flow‐brightened electrolytic tinplate is the intermetallic compound FeSn2.
O‐methylurea
Authors: Brown D. J. , Hoerger Earl
Published: July 2010

A practical method for producing O‐methylurea hydrochloride on a laboratory scale by methylation of urea is described in detail.
Investigations on organo‐tin compounds. II. The preparation of ethyltin compounds from a tin‐magnesium alloy
Authors: Van Kerk G. J. M. Der , Luijten J. G. A.
Published: July 2010

A new method is described for the preparation of ethyltin compounds, namely the interaction of a tin‐magnesium alloy of the composition Mg2Sn with ethyl bromide and chloride. This reaction yields tetraethyltin and/or various ethyltin bromides and chlorides. The type of solvent has an important influence on the course of the reaction.
Improvement of the corrosion resistance of tinplate by a chemical treatment
Authors: Britton S. C. , Angles R. M.
Published: July 2010

The corrosion of tin by hot sodium hydroxide solutions is accelerated by small additions of sodium chromate but is retarded by larger additions. Tinplate immersed in solutions containing sufficient remains bright and acquires an improved resistance to some other forms of corrosion; the pores in the tin coating rust less readily in the atmosphere and the tin surface becomes much more resistant to staining by sulphur‐containing materials and to oxidation on heating in air.

The best procedure and methods of test have been sought in order to provide a process for treatment of tinplate. Trials of canning soup in cans made from treated tinplate and in treated cans have shown the treatment to have practical value.

A reliable procedure is to immerse tinplate in a solution containing 10 g. of sodium hydroxide, 3 g. of sodium chromate and a small quantity of a wetting agent in 1 litre, for a minimum of 3 seconds at 90–95°. A test of the correct working of the solution is to immerse treated samples in a hot solution containing 10 g. of potassium sulphide (liver of sulphur) and 10 g. of sodium hydroxide in 1 litre at 90–95° for 30 seconds.
The products of combustion of chlorinated plastics
Authors: Coleman E. H. , Thomas C. H.
Published: July 2010

An examination has been made of the products of combustion of some chlorinated plastics. The main products were hydrogen chloride, carbon monoxide and carbon dioxide. Small amounts of carbonyl chloride were detected but they were unimportant compared with the concentrations of the other toxic gases.
Phase equilibria in sugar solutions. I. Ternary systems of water‐sucrose‐inorganic salts
Authors: Kelly F. H. C.
Published: July 2010

Ternary diagrams at 30° for systems water‐sucrose and KCl, NaCl, MgSO4, CaCl2, CdI2 or CuSO4 are presented. Interest centred on the invariant point (I.P.) enabled the conclusion to be reached that in these systems the composition at the I.P. is influenced more by the solubility of the second solute than by any other factor. High solubility of second solute favours low ‘purity’ at the I.P. with respect to sucrose, and vice versa.
Phase equilibria in sugar solutions. V. General Conclusions
Authors: Kelly F. H. C.
Published: July 2010

Analysis of results reported in Parts I—IV of this series has led to the following conclusions: (a) the less the second solute influences the solubility of sucrose in water, the lower the proportion of sucrose in solution at the invariant point (I.P.); (b) the greater the influence of sucrose on the solubility of the second solute in water, the greater the proportion of that solute in solution at the I.P.; and (c) the primary factor limiting the crystallization of sucrose from a solution with a second solute is the solubility of the second solute.
Biological treatment of cyanides, with and without sewage
Authors: Pettet A. E. J. , Mills E. V.
Published: July 2010

In experiments in which potassium cyanide or complex metal cyanides were added to sewage being treated in laboratory‐scale percolating filters, it was shown that, after causing a slight initial depression in oxidation of ammonia to nitrate, a concentration in any of the cyanides used of up to an equivalent of 4 p.p.m. of HCN had no further detectable effect on purification of the sewage, and that 99–100% of the cyanide was destroyed in the filters.

In filters acclimatized to cyanide, more than 99% of the cyanide was destroyed in solutions in sewage or in water containing at least 100 p.p.m. of HCN as potassium cyanide or the complexes of zinc or cadmium, and more than 75% was destroyed in similar solutions of the complexes of copper or nickel. The action appears to be biological, and may offer an alternative to chemical treatment for removal of cyanide from industrial waste waters.
Equilibration in molten polyamide mixtures
Authors: Ayers Cora W.
Published: July 2010

A method of partition chromatography has been used to discriminate between physical blends of 6,6‐and 6,10‐nylons and their copolymers. It has been proved that copolymerization proceeds rapidly when such polymers are melted together at 290° under nitrogen.
Analysis of the unsaturated hydrocarbons in fuel gases by infra‐red spectroscopy. I. Analysis of a town's gas
Authors: Towler J. H. , Holland B. H.
Published: July 2010

Carbonization gases and carburetted water gas contain from 2 to 7% of unsaturated hydrocarbons; these comprise a large number of compounds, but further information as to their precise nature and amounts is lacking. A method is described by which the unsaturated hydrocarbons are isolated from a gas in two stages; condensable compounds are first removed by refrigeration at —80°; unsaturated hydrocarbons remaining in the gas are then separated as bromine‐addition compounds. The two groups of compounds thus obtained are distilled into fractions and the fractions analysed quantitatively by infra‐red spectroscopy. It is shown that synthetic mixtures, similar in composition to the fractions obtained from a gas, may be analysed satisfactorily. The method has been applied to the analysis of a town's gas, from which the unsaturated hydrocarbons have been resolved into 37 individual compounds. From this, the composition of the crude benzole that would be obtained from the town's gas is given.
Inorganic chromatography on cellulose. XVI. The preparation of highly purified triuranium octaoxide from pitchblende
Authors: Arden T. V.
Published: July 2010

Uranium oxide (U3O8, triuranium octaoxide) of high purity is obtained from pitchblende by converting the uranium into uranyl nitrate, which is extracted by ether containing 3% (w/v) of nitric acid. The ethereal extract is passed through a column of activated cellulose, which retains the impurities present, giving a solution containing pure uranyl nitrate. The recovery of uranium is quantitative (over 99–9%), and the product is of sufficiently high purity to be used as an analytical and spectrographic standard.
Production of lanthanon and thorium compounds from monazite. III. Preparation of pure thorium nitrate
Authors: Pilkington E. S. , Wylie A. W.
Published: July 2010

A precipitation process is described for converting crude thorium oxalate or crude thorium phosphate into substantially pure thorium nitrate.

The process is based on the use of a sulphuric acid‐oxalic acid mixture to ‘leach’ the bulk of the phosphate from a thorium oxalate complex. A phosphate concentrate can be treated similarly, but is first treated with oxalic acid to convert it into an oxalate complex. Residual phosphate and sulphate are removed from the acid‐treated products by precipitation of thorium oxalate under specified conditions. Residual lanthanons, together with any remaining impurities, are separated from thorium by precipitation of a granular form of thorium ‘peroxynitrate’. Variables in the process have been studied and material flow sheets, based on laboratory investigations, are presented. If mechanical losses are ignored the yield of thorium from monazite exceeds 90%.

Application of the process to any type of thorium oxalate or phosphate concentrate is discussed, and details are given of the analytical determination in various thorium compounds of small quantities of phosphorus, cerium and mixed lanthanons.
The protective properties of various phosphate coatings on steel
Authors: Andrew J. F. , Clarke S. G. , Longhurst E. E.
Published: July 2010

Coatings of iron, manganese and zinc phosphates formed on steel by representative industrial immersion processes are compared, with special reference to their value in the prevention of rasting. The results are examined in the light of the thickness, composition and wear resistance of the coatings. Protective properties are relatively well developed in manganese phosphate coatings, but, since phosphating in practice normally constitutes only a part of a protective system involving organic coatings, iron and zinc phosphates can give adequate results in appropriate systems. A recent spot‐test of Russian origin, although at present not sufficiently well developed for inspection purposes, is likely to provide a useful additional tool for examining coatings. Variations in the coatings, in particular those that occur in the working range of a plain manganese phosphate process, have been examined and one untoward effect was identified, that due to adventitious copper contamination of the bath.
Hydraulic gradients on bubble‐cap plates
Authors: Bijawat H. C.
Published: July 2010

An equation is derived for hydraulic gradients on bubble‐cap plates on the basis of repeated acceleration and deceleration of liquid, and a gradient coefficient is postulated. Gradient coefficients have been computed from experimental data and correlated with water and air rates. The results are compared with the gradient‐factor correlation of Davies7.
Odour and molecular vibration. I. Quantum and thermodynamic considerations
Authors: Wright R. H.
Published: July 2010

The physical basis of odour is uncertain because the odours of compounds have never been satisfactorily correlated with their other characteristic properties. The suggestion that a particular odour is a result of a particular molecular pattern is qualitatively reasonable and can be tested experimentally. It is shown on quantum grounds that the vibrations in question must correspond to absorption in the far infra‐red, so that the most suitable avenue of attack on the problem is through the Raman effect.
The determination of rye flour in urea‐formaldehyde syrups
Authors: Haslam J. , Jeffs A. R.
Published: July 2010

A method has been developed for the determination of rye flour (up to 8%) in urea‐formaldehyde syrups. The method is based on hydrolysis of the syrup with hydrochloric acid solution and subsequent determination of the glucose in the hydrolysis products with flavianic acid in the presence of formaldehyde; the colour produced is measured in a Spekker absorptiometer. By using appropriate calibration curves, the test may be extended to the determination of other flours and starches, e.g. wheat flour and potato flour, which may be employed as thickening agents in urea‐formaldehyde syrup.
The solubility of oxygen in pure water and sea‐water
Authors: Truesdale G. A. , Downing A. L. , Lowden G. F.
Published: July 2010

The solubility of oxygen in pure and in saline water between 2°and 40°has been determined by using a modification of the Winkler titration technique. The values found have, in some cases, been lower than those generally accepted by as much as 4%. On applying these new solubilities to the determination of rates of solution in well mixed water, satisfactory agreement with the Adeney & Becker law of aeration is obtained.
The determination of fluorine in piltdown and related fossils
Authors: Hoskins C. R. , Fryd C. F. M.
Published: July 2010

The special precautions deemed necessary in estimating the fluorine content of the bones and teeth of Piltdown and associated remains are described. An account of the precise technique employed is given, illustrated by some typical results.
The chemistry of styrenated oils
Authors: Crofts J. B.
Published: July 2010

The interaction of styrene with the methyl esters of a number of drying‐oil acids and with a dehydrated castor oil has been studied. The experiments were carried out under a single set of reaction conditions, at 140°in the absence of oxygen or added catalyst. The products were separated into four types and their nature elucidated by chemical and spectroscopic analysis and molecular weight determination. Both the conjugated‐triene (α‐elaeostearic) and conjugated‐diene (9 : 11‐linoleic) systems formed true copolymers of high molecular weight with styrene, and also Diels‐Alder adducts containing one styrene molecule combined with one fatty ester molecule. The non‐conjugated linoleic and linolenic esters did not copolymerize with styrene. With methyl 9 : 12‐linoleate the high‐molecular‐weight product was almost indistinguishable from polystyrene. With methyl 9 : 12 : 15‐linolenate it was found that a small proportion of ester was attached to the polymer chain, probably by chain transfer. With dehydrated castor oil containing a mixed ester of conjugated and non‐conjugated acids, copolymers of relatively low ester content were obtained, and not mixtures of copolymers and polystyrene.
Organo‐phosphorus compounds. I. Interaction of organic phosphorohalogenides with solid alkalis: A new synthesis of schradan
Authors: Pianka M.
Published: July 2010

Tetramethylphosphorodiamidic chloride reacts with alkali‐metal hydroxides via the alkali salt to give the anhydride (bisdimethylaminophosphonous anhydride, octamethylpyrophosphoramide, schradan) in high yield. The less stable bromide gives a lower yield of schradan. The fluoride does not yield schradan under these conditions, nor when treated with water in the presence of pyridine. Although diethyl phosphorochloridothionate yields the corresponding anhydride when treated with water in the presence of pyridine, no anhydride is formed when it is caused to react with an alkalimetal hydroxide in an inert solvent. Diethyl phosphorochloridate yields the anhydride when treated as above, but diethyl phosphorofluoridate does not. A synthesis of decamethyltriphosphoramide is described.
The polyphosphates of cadmium, zinc and lead: The character, composition and behaviour of their complexes
Authors: Bobtelsky M. , Kertes S.
Published: July 2010

This study is the second in a series of investigations of polyphosphates, in which only physical methods are used.

The composition of the salts and complexes were studied by heterometric (photometric study of suspensions), pH and conductometric methods. The pyrophosphate anion‐complexes identified are: [MII(P2O7)2]6‐ and [MIIP2O7]2‐, where M represents the metal. The precipitate probably has the structure M3II[MII(P2O7)2]. The tripolyphosphate anion‐complex obtained is: [MIIP3O10]3‐. The precipitate probably has the composition M3II[MIIP3O10]2.

The superiority of the heterometric method over the other methods used was demonstrated in this investigation by the greater variety of physical and chemical properties detected.
Some determinations of liquid‐phase diffusion coefficients by means of an improved diaphragm cell
Authors: Lewis J. B.
Published: July 2010

The integral diffusion coefficients of acetone, acetic acid, benzoic acid, diethylamine and uranyl nitrate in water and in a number of organic solvents have been determined at 20°. The mutual diffusion coefficients of four partially miscible solvent‐water pairs have also been determined, the solvents being aniline, ethyl acetate, furfuraldehyde and isobutanol.

An improved diaphragm cell was used for these measurements, both compartments being agitated by electromagnetically driven stirrers. The existence of a critical stirring rate, different for each cell, below which the cell constant varied was demonstrated.

An Appendix is included demonstrating how differential diffusion constants could be determined directly with a cell of this type.
The partial pressure of hydrofluoric acid over solutions of potassium fluoride in hydrofluoric acid
Authors: Baines A. , Davies A.
Published: July 2010

Statistical examination of a section of Cady's experimental results relating the partial pressure of hydrofluoric acid over solutions of potassium fluoride in hydrofluoric acid to composition and temperature yields the equation:

where P is the partial pressure of hydrofluoric acid (mm. Hg), T is the absolute temperature and C is the concentration of hydrofluoric acid in the solution, expressed as a weight percentage. Although this equation is subject to bias the error in values of P calculated from it may be presumed to be less than 5% in the region of 38–44% concentration and at temperatures of 70–150°C. A Table is given of the calculated values of the partial pressure of hydrofluoric acid within this region at 0.5% intervals of concentration and 5.0°intervals of temperature.
Further investigations into the corrosion of a steel surface by condensed films of sulphuric acid
Authors: Kear R. W.
Published: July 2010

Following previous studies of the corrosion of cooled steel probes by flue gases containing SO2 and SO3, further experiments have shown that: (a) for tests up to 24 hours there is a reduction in the rate of corrosion after 8 hours, (b) in the presence of corrosion products the corrosion continues even when the metal temperature is raised to or above the acid dewpoint temperature. A mechanism is briefly discussed.
Colour reactions of 2:6‐dichloroquinone chloroimide with derivatives of glyoxaline‐2‐thiol
Authors: Searle C. E.
Published: July 2010

A large number of glyoxaline‐2‐thiols and some 2‐alkylthioglyoxalines react with 2:6‐di‐chloroquinone chloroimide at pH 8 to give coloured products which are in most cases soluble in chloroform. The mechanism of the reactions is briefly discussed.
The corrosive nature of combustion gases from carbon monoxide flames containing sulphur oxides
Authors: Whittingham G.
Published: July 2010

Mild steel corrosion probes have been used to determine the relation between surface temperature and amount of iron corroded by the flue gases of relatively low moisture content from a diffusion flame of carbon monoxide, to which additions of sulphur dioxide were made. Complementary measurements have been made of the percentage conversion of sulphur dioxide to sulphur trioxide and of the rates of acid build‐up on a dewpoint meter. Over the temperature range employed, corrosion showed a maximum at 66°to 70°, and humidity of combustion air was found to have a significant effect on corrosion.

From the dewpoint meter readings and other data, theoretical rates of acid deposition on the corrosion probe have been calculated and these and the experimental values are compared and discussed.
Improved syntheses in the pyrimidine series. IV. N‐methyl derivatives of 4: 5‐diaminopyrimidine
Authors: Brown D. J.
Published: July 2010

4‐Amino‐5‐methylaminopyrimidine has been synthesized by reduction with lithium aluminium hydride of the formyl group in 4‐amino‐5‐formamido‐2‐methylthiopyrimidine followed by removal of the 2‐substituent. A route to 5‐amino‐4‐hydroxy‐6‐methylaminopyrimidine is described. The Whitehead synthesis has been extended to the use of cyanoacetic acid as a reactant. Decarboxylation of the resulting 4‐amino‐5‐carboxy‐3‐methyl‐2‐pyrimidone, however, gave unexpectedly 2‐hydroxy‐4‐methylaminopyrimidine. Several improvements in the preparation of known related (methylated) compounds, including the first isolation of 5‐amino‐1‐methyl‐4‐methylamino‐2‐pyrimidone are described.
The determination of very low concentrations of hydrogen sulphide in gas—I
Authors: Prince C. G. T.
Published: July 2010

The determination of low concentrations of hydrogen sulphide in gas has been investigated. A modified calibration technique has been developed for the methylene blue method and its accuracy verified volumetrically and gravimetrically. Employing the methylene blue method as a primary standard, the relation between optical density and sulphur content of lead sulphide stains, obtained by passing gas through absorbent paper, has been replotted, using a specially designed photoelectric densitometer.
A comparison of the properties of various preparations of sodium alginate
Authors: Vincent D. L. , Goring D. A. I. , Young E. Gordon
Published: July 2010

Fifteen specimens of sodium alginate from various brown algae, including species of Laminaria, Fucus and Ascophyllum, have been prepared in the laboratory or obtained from commercial sources. Tests on these samples included measurements of optical rotation, ionic mobility, rate of sedimentation, viscosity and content of sulphated ash. Most specimens were homogeneous by electrophoresis and in the ultracentrifuge. The content of alginate of the samples varied from 61.7 to 99.6%. Rate of sedimentation was strongly dependent on concentration. Electrophoretic mobilities varied only slightly. Viscosity varied much more widely than other physical properties and was the best criterion of state of polymerization. Fucoidin was detected as impurity in some preparations.

From the best preparations examined the following values were obtained: [α]d20° = −133°to −140°; μ = 2.9 to 3.1 × 10−4 cm.2 sec.−1 volt−1 at 25°, pH 5.5, I 0.05; s40 = 1.3 to 1.6 S (c = 0.5%); sulphated ash = 34.0 to 35.9%. Viscosity varied from 2 to 20 centistokes at 25°in 0°1n‐NaCl (c = 0.25% w/w). Values for [η] varied from 3.6 to 19.2 corresponding to a degree of polymerization of 210 to 1,100 and particle weight of 42,000 to 222,000. The specific refractive increment of sodium alginate was found to be 0.160 g.−1 cm.3.
The effects of repeated washing of tinned steel with alkaline solutions on its resistance to rusting
Authors: Britton S. C. , Michael D. G.
Published: July 2010

The rates of corrosion of tin specimens either intermittently or continuously immersed in several alkaline solutions have been compared. Similar solutions have been used to wash specimens of tinned steel that were exposed to the weather between washes in imitation of the service life of some tinned steel containers.

The relative corrosive action of various solutions on intermittently immersed tin depends on the experimental conditions and may differ from that observed when the metal is immersed continuously. The results obtained with short periods of immersion are strongly influenced by the variation with the nature of the solution, the temperature and the condition of the metal surface, and of a period of delay between immersion of the metal and the onset of corrosion. A high rate of corrosion during the period between removal of the metal from the test solution and rinsing also introduces a potential cause of variation in the results of intermittent‐immersion tests.

The deterioration in the protective quality of a tin coating on steel periodically washed in an alkaline solution can be predicted only moderately well from measurements of the corrosion rate of tin immersed in the solution. This deterioration results more from the enlargement of new pores formed in the coating during periods of exposure to the weather than from general dissolution of the tin, and silicates appear to restrain this action.

In the conditions of the tests employed, with solutions of equivalent caustic alkalinity, sodium hydroxide, carbonate and phosphate had similar effects; sodium silicate (2 : 1) produced less deterioration; sodium metasilicate much less and sodium silicate (1 : 2), almost none. Additions of sodium sulphite to the washing solution had a negligible effect but additions of sodium chromate preserved both tin and steel. Additions of sodium hypochlorite either to washing or rinsing solutions accelerated deterioration of the coating except when made to solutions of sodium metasilicate or of sodium silicate (1 : 2).
Factors influencing the time of gelation of acid ‘modified’ sodium silicate
Authors: Heald I. A. , Coates K. B. , Edwards J. E.
Published: July 2010

In one method of preparing ‘modified’ sodium silicate, a coagulant of increasing importance in water treatment processes, a solution of sodium silicate is treated with an acid, allowed to age and finally diluted according to a recommended procedure. The changes which occur during the ageing time are retarded by the final dilution. If the ageing time is much too long, the product gels; if too short, the diluted sol is a less efficient coagulant than one aged for the correct time. The time of gelation is therefore of considerable importance in the technology of making the reagent.

The literature contains scattered references to the effect of such variables as concentration on the gel time of ‘modified’ sodium silicate, but few systematic measurements appear yet to have been reported on the influence of other factors. The results of such a study are given in this report. The data are set out in graphical form from which most of the facts required in practice can be obtained. The conclusions of especial interest are: (a) silica sols exhibit the greatest instability when the pH value is about 7.5 whatever acid is used for neutralization; (b) the presence of neutral salts hastens gelation; (c) the effect of using sodium silicate containing more Na2O (i.e. of a lower grade) and neutralizing to the same residual alkalinity can be explained quantitatively in terms of the extra sodium salt introduced by such a method of preparation.
Analytical applications of sodium lauryl sulphate I.—The volumetric determination of barium
Authors: Gwilt J. R.
Published: July 2010

A method is developed in which barium is precipitated from aqueous solution by addition of sodium lauryl sulphate; excess of the latter is then titrated with a suitable quaternary ammonium compound. Contrary to expectation, a number of cations interfere.
A preliminary investigation on the chemical composition of sphagnum moss and peat
Authors: Black W. A. P. , Cornhill W. J. , Woodward F. N.
Published: July 2010

Sphagnum, heather (Calluna vulgaris) and peat samples have been analysed for total ash, crude fats, Kjeldahl nitrogen, cellulose, total reducing substances, reducing sugars and the individual sugars glucose, galactose, arabinose and xylose. Xylose, mannose, fucose and ribose were isolated from a peat hydrolysate and characterised. Fructose and fructose‐containing oligosaccharides were found chromatographically in the fresh Sphagnum. A polysaccharide has been isolated from peat in which glucose is the principal sugar along with mannose, galactose, xylose, an unidentified uronic acid and a trace of rhamnose. The free amino‐acids of Sphagnum and peat, and the amino‐acids in the hydrolysates have been examined chromatographically. Chloroform extraction of Sphagnum gave a sterol fraction resembling ‘β’‐sitosterol.
Measurement of molecular weight by the light scattering method experimental procedure and interpretation of results
Authors: Cleverdon D. , Harvey L. , Laker D. , Smith P. G.
Published: July 2010

The operations which have to be performed to convert measured light‐scattering data to estimates of molecular weight and size are considered. It is shown that the estimate of the root‐mean‐square chain length can be seriously in error if account is not taken of the effect of molecular weight heterogeneity upon the particle scattering factor. The Zimm method is applied to data from an instrument with three angles of observation only, and the estimates so obtained are compared with those obtained using the dissymmetry method.

Points of actual experimental procedure are discussed together with the method of absolute calibration. A complete set of data for polystyrene in toluene is given.
Observations on the decay of synthetic anionic detergents in natural waters
Authors: Hammerton C.
Published: July 2010

The effect of storage on various synthetic anionic detergents in low concentration in natural waters has been studied. Some compounds are easily oxidised by the bacteria normally present in such waters, but those compounds found in present day household packages are generally resistant.

An attempt has been made to find the reason why certain compounds are susceptible, and others resistant, to bacterial oxidation. The deciding factor appears to be the nature of the alkyl group in the detergent; straight‐chain compounds are easily attacked, but branched‐chain compounds show resistance.
A further note on the chemical denaturation of groundnut protein and fibre formation
Authors: Naismith W. E. F.
Published: July 2010

An ultracentrifugal examination of groundnut protein treated with various bases has been made. It has been shown that only bases with a dissociation constant higher than about 10−1cause an appreciable reduction in the molecular weight of the protein and are suitable for fibre formation with the protein.
The anaerobic corrosion of tin in anthocyanin solutions and fruit syrups
Authors: Salt F. W. , Thomas J. G. N.
Published: July 2010

Chrysanthemin, the main constituent of the colouring matter of Victoria plums and raspberries, has been found to act as a cathodic depolarizer for the corrosion of tin by citric and malic acids. About 5 moles of chrysanthemin are required for the dissolution of 1 mole of tin but it is provable that this equivalence varies with the concentrations of anthocyanin and its tin complex. Rate constants have been determined for the reaction of tin with a malic acid solution of chrysanthemin and with the anaerobic syrup from bottled yellow plums, Victoria plums, and raspberries. The amount of tin dissolved per unit volume of the syrups increased in the order in which they have been mentioned and is greater than would be expected from their anthocyanin contents, indicating that other depolarizers are present in the fruit syrups.
Determination of the mean particle size of fine black powders by the measurement of reflectivity
Authors: Rose H. E.
Published: July 2010

It is shown that the mean particle size of ‘black’ powders of size less than about one micron can be deduced from the reflectivity of the powder; furthermore the mean size of the ultimate particles in an aggregated or pelleted material may be readily determined.

A simple apparatus for the measurement of the reflectivity is described; suitable techniques for the formation of the reflecting surface are given and it is shown that the determinations require considerably less time than, and their accuracy compares satisfactorily with, those of any alternative technique.

The results suggest that this technique, as well as being a useful tool for the routine measurement of particle size, may be an extremely sensitive means for the investigation of structural differences in very fine powders.
Kinetics of catalytic oxidation of sulphur dioxide for comparison of fixed and fluid bed reactors
Authors: Goldman Max , Canjar L. N. , Beckmann R. B.
Published: July 2010

The kinetics of the oxidation of sulphur dioxide over a commercial vanadia catalyst in confined and fluidized beds have been investigated under various operating conditions. The reaction rates for both the confined and the fluidized operation were correlated by an equation based on the assumption that the reaction rate was controlled by the specific surface reaction between activatedly adsorbed atomic oxygen and activatedly adsorbed sulphur dioxide at high mass velocities where diffusional effects are negligible. The general rate equation is:\documentclass{article}\pagestyle{empty}\begin{document}$ \[r = \frac{{kE\sqrt {K_{O_2 } .K_{3O_2 } } \left[{p_{SO_2 } \sqrt {p_{O_2 } } - {{p_{SO_3 } } \mathord{\left/ {\vphantom {{p_{SO_3 } } K}} \right. \kern-\nulldelimiterspace} K}} \right]}}{{1 + \left[{\sqrt {p_{O_2 } \cdot K_{O_2 } } + p_{SO_2 } \cdot K_{SO_2 } + p_{SO_3 } \cdot K_{SO_3 } } \right]^2 }} \] $\end{document}

The individual reaction rate data were correlated by assuming the adsorption equilibrium and reaction velocity constants were the same for both the confined and the fluidized operations. The developed rate equations differ only in the effectiveness factors for the specific mode of gas‐solid contacting.

This study gives some insight into the practical problem of applying fixed bed catalytic data to fluidized operation in the absence of fluidized bed data or vice versa. It also demonstrates the possibility of correlating fixed and fluidized bed data with a single parameter.

It is doubtful if, as is generally supposed, a fluidized bed under low mass velocity conditions behaves as a fixed bed.
The microdetermination of dissolved oxygen in water. II. the design of water‐sampling vessels
Authors: Potter E. C.
Published: July 2010

The errors introduced by the use of the McLean sampling vessel for determination of the dissolved oxygen content of water up to 0·1 p.p.m. are discussed. A new apparatus is developed by means of which a precision of ± 0·0007 p.p.m. in the determination may be obtained. A modification for use with warm water‐samples is described.
The specific heat of coal tar distillates
Authors: Briggs D. K. H. , Popper F.
Published: July 2010

Specific heats of a large number of coal tar distillate fractions have been measured and the following relationship, which will predict values to an accuracy of ± 5% for the temperature range 20–180°, has been derived by means of statistically designed experiments: Cp = 1/d20 (0·1758 + 0·2138 d20 + 0·000861 t) + x(0·00216 – 0·00000528 ib) where Cp is the specific heat, cal./g.°c

d20 is the density of the sample at 20°, g./ml.

t is the temperature, ° c

tb is the volumetric average boiling point of the sample, ° c

x is the tar acid content, % by volume.
The use of statistics in corrosion research
Authors: Mann G. M. W.
Published: July 2010

The principles underlying the use of statistical calculation of probability and correlation and variance of results are outlined and their application to examination of corrosion problems is discussed.
Solubility studies on arachin
Authors: Kelly Kirsteen O. , Thomson R. H. K.
Published: July 2010

A study has been made of the solubility of arachin under conditions approximating to those of the ‘Ardil’ manufacturing process. This was done by investigating the four‐component system, water, sodium hydroxide, hydrochloric acid and arachin. The results are represented in the form of a tetrahedron and the limits of complete solubility of arachin above and below the isoelectric point are shown. The effect of salt concentration on the solubility of arachin below pH 5·0 has also been studied.
Ternary liquid equilibria: Methanol–water–esters
Authors: Rao R. Jagannadha , Rao C. Venkata
Published: July 2010

Mutual solubility and tie‐line data are presented for four ternary liquid systems containing methanol, water and n‐butyl acetate, pentyl acetate, ethyl propionate and ethyl butyrate as solvents at 30°. For comparison, equilibrium data reported in the literature for the system methanol–water–ethyl acetate at 20° have been plotted on the saturation isotherm, equilibrium distribution and selectivity diagrams. The tie‐line data for all the systems are satisfactorily correlated by the methods of Hand and Othmer–Tobias, and the plait points are located by the method of Treybal, Weber & Daley. For all the systems, it is found that the distribution of methanol is in favour of the aqueous phase. Although the distribution coefficient is higher for ethyl acetate, ethyl butyrate is found to be the most selective of the solvents studied.
Dinuclear novolaks from m‐ and p‐cresol
Authors: Godfrey L. E. A. , Hawkins E. G. E. , Jenkins P. A.
Published: July 2010

The six two‐ring novolaks theoretically obtainable from m‐cresol and formaldehyde have been synthesized and the three dinuclear novolaks involving one molecule each of m‐cresol and p‐cresol have been prepared. The uniformity of each product is confirmed by paper chromatography.