摘要:

AbstractThe paper deals with the machinery required for modern surface‐dressing work. For convenience the subject is divided as follows:Binder distributorsGritting and loading machineryRollersThe principles involved in the design and operation of the common types of binder distributor are discussed, and photographs arc shown of representative machines. Common faults occurring in the work done by the different distributors arc considered. Tests are described for measuring transverse and longitudinal uniformity of binder film, and results are quoted to show the quality of some of the work being done at the present time; practical tolerances are suggested.Several types of gritting machine arc described and the results given of an investigation made on 12 sites to compare the number of men used and the output obtained from four types of primer. A single result is given to show how fast a normal gang can spread chippings if not held up for materials. Some measurements have also been made on the transverse and longitudinal variation in the rate of spread of chippings by the different methods. Brief descriptions are given of three modern methods of loading chippings (self‐loading elevator, the mechanical shovel and the clam‐shell grab) and some figures are given for the output of each. The size of roller required for finishing the dressing is discussed and an experiment is described in which sections have been laid with different weights of roller and without any roller a

ISSN:0368-4075    

DOI:10.1002/jctb.5000690201

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractThe static electrification of a number of metal dusts has been measured in two standard experiments; these results, together with the electrostatic energy required for the ignition of dust clouds of metal powders, provide a basis for the estimation of the electrostatic hazard likely to be encountered in handling quantities of materials.

ISSN:0368-4075    

DOI:10.1002/jctb.5000690202

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractMethods of determination of the silica and halogen contents of some organic compounds of silicon, including volatile and moisture‐sensitive substances, arc describe

ISSN:0368-4075    

DOI:10.1002/jctb.5000690203

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractA sensitive electronic thermostat control unit is described in which a thermistor is used as the sensing element. The output from the thermistor bridge network, after amplification, provides grid potential amplitude control of the current in a gas‐filled triode, the anode circuit of which contains the heating element. The unit is of the proportionate control type, and it can readily be adjusted to provide temperature control to within 0·025°C. at temperatures up to 12

ISSN:0368-4075    

DOI:10.1002/jctb.5000690204

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractGel strength and viscosity studies have been carried out employing a series of pectins obtained by degrading citrus pectin by grinding for various times in 3 ball mill. As degradation increased, the quantity of material estimated as calcium pectate, but not contributing to gel formation, increased and the slope of the straight line representing the gel strength and square of the concentration relationship became less. It is shown that this slope bears a linear relationship to the limiting viscosity values for the pectin in aqueous solution and the nitro‐ester in acetone solution, and that it is proportional to the Young's modulus of the fibrils constituting the ge

ISSN:0368-4075    

DOI:10.1002/jctb.5000690205

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractContrary to the previous opinion that alkali refining reduces considerably the vitaminApotency of fish liver oils, it has been found that under usual refining conditions the neutralization with alkalis results in increased potency. The increase is approximately proportional to the free fatty acid content of the original oil. The amount of vitaminAcarried away by free fatty acids and “impurities” during the refining process has been determi

ISSN:0368-4075    

DOI:10.1002/jctb.5000690206

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractPhloroglucinol in the presence of hydrochloric acid gives a red colour with certain aldehydes, lignified tissue, the mould product viridin and oxidized hydroquinone; it is also said to give a red dour with compounds containing allyl groups. These reactions have been investigated. A number of aldehydes and oxidized hydroquhones give the reaction but pure allyl compounds do not. The aldehydes and hydroquinones may be distinguished by the use of phloroglucinol derivatives in place of phloroglucinol itself.

ISSN:0368-4075    

DOI:10.1002/jctb.5000690207

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractA study has been made of the ternary system, water‐methanol‐xylene, at 20°, 30° and 50°c. The system exhibits density inversion of the conjugate solutions and the compositions of the conjugate phases of equal density have been dete

ISSN:0368-4075    

DOI:10.1002/jctb.5000690208

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY

摘要:

AbstractA series of laboratory tests designed to estimate the relative efficiency of bitumen and other materials used as textile rotproofing agents has been carried out, using a new form of testing apparatus for the purpose. Pre‐treatment with cuprammonium followed by bitumen saturation, or a single treatment with a mixture of bitumen and cresylic acid, provides better rot‐protection than bitumen al

ISSN:0368-4075    

DOI:10.1002/jctb.5000690209

出版商:John Wiley&Sons, Ltd    

年代:1950

数据来源: WILEY