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This paper aims to study microwave pad dyeing process for wool fabric. Influences of various dyeing process conditions including galactomannan dosage, urea dosage, sodium bisulphite dosage, pH value, microwave irradiation power, treating time and cold batching time before microwave fixation on K/S values were analysed. The colour yield, fixation and levelness were compared between microwave fixation and cold batching fixation.

Colour yield (K/S values) was calculated using a Datacolor SF650 colour measuring and matching instrument (10° standard observer, CIE D65 light source Measuring; Datacolor, USA) and was used to determine the depth of the shade of dyed wool fabrics. Levelness of dyeing was evaluated also using the Datacolor SF650 colour measuring and matching instrument by measuring average deviation (S), range (P) of the maximum and the minimum for lightness (L), chroma (C) and hue (h), and balanced colour difference (ΔE) at 20 specified uniform locations on the wool fabrics. The colour difference was calculated as per the equation ΔE=(ΔL2+Δa2+Δb2)1/2 as appearing in the Experimental section. Fixation was determined using a Datacolor SF650 colour measuring and matching instrument by measuring ratio the of K/S for wool fabrics that were rinsed, washed, neutralised and then dried, and wool fabrics that were dried after fixation without washing. The pH of the padding solution was evaluated using a PHSJ-4A PH meter (Datacolor, USA). SEM analysis was done on JEOL JSM-5600LV machine (JEOL Ltd, Japan).

This study is based on application of microwave technology in the processing of silk.

It was found in laboratory experiments that uniform dyeing and deeper colour can be achieved throughout the microwave pad dyeing process for wool by using galactomannan. The novel process could reduce the dyeing time and the energy consumption of the traditional cold pad-batch dyeing process for wool fabric.

The purpose of this paper is to study the effective procedure for blocking and deblocking isocyanate by sodium bisulphite with special cosolvent and dropwise method.

A number of analytical techniques, including Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC) and Thermo gravimetric analyser (TGA) were employed to assess the reactions between isocyanates and sodium bisulphite, water, cosolvent, also the deblocking temperature of blocked isocyanates.

The blocked isocyanates reacted with sodium bisulphite, water and cosolvent via a special procedure. It was found that the − NCO functional groups of the isocyanates were completely blocked by sodium bisulphite and a new method for determining the lowest deblocking temperature of the blocked isocyanates was described. It was revealed that the deblocking temperature of blocked isocyanates by sodium bisulphite was lower than others.

The paper provides some useful information about the blocking and deblocking of isocyanate, which would be helpful for the preparation of blocking and deblocking isocyanate, and guiding the practical applications of blocked isocyanate.

The investigation found that the sodium bisulphite was a very efficient blocking agent for isocyanates at the room temperature via the special procedure developed. On the basis of emulsion polymerisation theory, polymer isocyanates were blocked by sodium bisulphite, which realised the new breakthrough effectively by means of controlled temperature, stirring speed and optimum dropwise speed in the whole reaction system. Meanwhile, the special cosolvent could improve the intermiscibility of isocyanate in sodium bisulphite aqueous solution, reduce the side reaction of isocyanate with water and accelerate reaction rate of isocyanate with sodium bisulphite. If no cosolvent was present, the blocked system would not be homogeneous.

In a Northern city, which claims to have more than 12,000 Commonwealth immigrants, mostly of Asian origin—Pakistanis and Indians, an increasing number of whom have been joined by their wives and families, there was instituted in 1965 a routine examination of their children before school entry, later extended to children of immigrant origin already in the schools. This examination extended to haemoglobin estimation, tuberculin‐testing and, equally important, examination of the stools for pathogens and parasitic ova. 419 entrants were examined in the first half of 1965 and 898 pupils. Parental co‐operation must have been excellent, as parents all agreed, without exception, to the special examination, although to some extent, there might have been considered legal authority in the current School Health Service (Medical Inspection) Regulations made under the Education Act, 1944. We are not aware of any report of intestinal pathogens, but helminth infestations were reported (Archer D. M., Bamford F. N., and Lees E., Helminth Infestations in Immigrant Children, 1965, Brit. Med. J., 2, 1517), from which it appears 18·6% carried five types of worm, of which the commonest was hookworm. It would be fair to assume that helminth infestation, indicating as it does, exposure to food infections, water‐borne disease and environment generally, is an index of gastro‐intestinal infection and the presence of pathogens, including the carrier state.

The discovery, first of the chemical bond between rubber and steel, then of various techniques for bonding all types of rubber to metal, led to the development after the first world war of what was in effect a new and extremely versatile structural material for anti‐corrosive applications combining the high mechanical strength and rigidity of steel with the remarkably efficient chemical resistance of rubber.

By means of dip‐ or spray‐coating with polythene powder, a complete protective covering can be applied in one operation to metal articles of the most complex shape, such as the soap and sponge rack shown overleaf. Dip‐coating in particular is a process which can be carried out with very simple equipment, yet on the other hand it is adaptable to mass production requirements.

Natural selection—survival of the fittest—is as old as life itself. Applied genetics which is purposeful in contrast to natural selection also has a long history, particularly in agriculture; it has received impetus from the more exacting demands of the food industry for animal breeds with higher lean : fat and meat : bone ratios, for crops resistant to the teeming world of parasites. Capturing the exquisite scent, the colours and form beautiful of a rose is in effect applied genetics and it has even been applied to man. For example, Frederick the Great, Emperor of Prussia, to maintain a supply of very tall men for his guards—his Prussian Guards averaged seven feet in height—ordered them to marry very tall women to produce offspring carrying the genes of great height. In recent times, however, research and experiment in genetic control, more in the nature of active interference with genetic composition, has developed sufficiently to begin yielding results. It is self‐evident that in the field of micro‐organisms, active interference or manipulations will produce greater knowledge and understanding of the gene actions than in any other field or by any other techniques. The phenomenon of “transferred drug resistance”, the multi‐factorial resistance, of a chemical nature, transferred from one species of micro‐organisms to another, from animal to human pathogens, its role in mainly intestinal pathology and the serious hazards which have arisen from it; all this has led to an intensive study of plasmids and their mode of transmission. The work of the Agricultural Research Council's biologists (reported elsewhere in this issue) in relation to nitrogen‐fixing genes and transfer from one organism able to fix nitrogen to another not previously having this ability, illustrates the extreme importance of this new field. Disease susceptibility, the inhibition of invasiveness which can be acquired by relatively “silent” micro‐organisms, a better understanding of virulence and the possible “disarming” of organisms, particularly those of particular virulence to vulnerable groups. Perhaps this is looking for too much too soon, but Escherichia coli would seem to offer more scope for genetic experiments than most; it has serotypes of much variability and viability; and its life and labours in the human intestine have assumed considerable importance in recent years. The virulence of a few of its serotypes constitute an important field in food epidemiology. Their capacity to transfer plasmids—anent transfer of drug resistance— to strains of other organisms resident in the intestines, emphasizes the need for close study, with safeguards.

The purpose of this paper is to evaluate the efficiency of commercial silica, silica fume-waste (SF) and modified silica fume-waste (mSF) as reinforcing filler in acrylonitrile-butadiene rubber (NBR) and ethylene propylene diene monomer (EPDM) through the mixing process of rubber. The composites were prepared using different loadings of silica fume and commercial silica in EPDM and NBR composites. Structural characterization of silica and SF was done using X-ray fluorescence and scanning electron microscopy (SEM). The surface of silica fume waste was modified using poly methyl methacrylate/butyl acrylate through emulsion polymerization to increase the interaction between silica and rubber, then consequently better dispersion in rubber matrix was obtained. The mSF waste was characterized using FT-IR spectra and transmission electron microscopy.

The investigated rubber mixes and vulcanizates were evaluated by measuring the curing characteristics, mechanical testing, thermogravimetric analysis and morphological studies (SEM). The mechanical properties of composites including tensile strength, elongation at break and modulus were estimated and analyzed.

The results revealed that the composites (NBR and EPDM) containing mSF as filler exhibited better rheological and mechanical properties compared to unmodified silica waste and commercial silica. The SEM analysis indicated that the mSF was homogeneously dispersed through the surface of NBR and EPDM composites. Also, results showed that (NBR and EPDM) composites exhibited remarkable improvements in tensile strength, elongation at break and hardness in the presence of mSF; they also showed an increase in the thermal stability. This means that the treatment of surface SF can improve its dispersion in rubber.

Silica cannot be applied in rubber matrix without surface modification because of their incompatibility; their dispersion is not good without surface modification.

The modified silica surface is considered as effective reinforcing filler which can replace other fillers because of its lower surface energy and enhanced intercalating behavior in rubber.

This study is just a start in establishing rubber projects with wide applications in the industry and providing a cheap local product while preserving the quality and that is the use of factory waste, which helps in protecting the environment from pollution.

mSF is cheap with relatively high purity, which make rubber/mSF composites appear as new grade of material that can be used in different media rather than rubber.

Stainless steel is rapidly achieving pre‐eminence as a favoured material of construction due, no doubt, to the fact that for many applications in chemical plant it is the only material that can fulfil the stringent requirements as well as ensuring minimum maintenance costs. This article describes the constitution of stainless steels and their physical, mechanical and corrosion properties. Finally, their importance to the chemical plant designer is surveyed.

The mechanisms of the deblocking reaction of the polyurethane with blocking agent were investigated in detail relatively using thermogravimetric analysis (TGA), Fourier transform infrared spectrometry (FTIR) and X-ray photoelectron spectroscopy (XPS). This kind of method for polyurethane as the application of wood adhesives can provide the conditions of application and the main theoretical basis.

The blocking rate and latex particle size distribution were determined using the titrimetric analysis and the laser particle analysis, respectively. TGA, FTIR, XPS and differential scanning calorimetry were used to investigate the deblocking temperature and time of the blocked isocyanate in detail.

The results indicated that the blocking rate was approximately 97 per cent and the average particle size was 360 nm. The results of laser particle analysis have confirmed that the dispersivity of the blocked polyurethane emulsion was good. XPS results showed that the amount of –O = C-N-benzyl groups increased with an increasing deblocking temperature and subsequently reached equilibrium. In summary, the blocked isocyanate was deblocked at temperatures ranging from 50 to 90°C.

An important approach in future wood adhesive work would be to gain access to man-made board application data.

The paper provided some useful information about deblocking mechanisms of blocked polyurethane that would be helpful to guide applied practical applications as wood adhesive.

To promote China’s wood processing technology progress and solve the problem of shortage of the natural quality of wood is of important practical significance.

The paper is the first to use the XPS characterisation method to characterise deblocking polyurethane solution.

A newly developed polyvinyl acetate (PVA) emulsion latex for adhesive has been prepared by the semicontinuous process using a newly developed octyl aldehyde sodium bisulphite‐potassium persulphate redox pair initiation system. In this work the amount of polyvinyl alcohol (PVA) as a protective colloid has been changed and it was found that only a little amount of (PVA) together with the newly developed adduct could cause a stable latex with excellent mechanical properties for bonding wood which favours this redox system in large industrial applictions. Also monodisperse latex particles with low polydispersity index can be prepared by using 1% PVA coupled with the newly developed redox system. Finally the developed latex has been incorporated and the corresponding shear strength were measured.