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Six ruminal-cannulated nonlactating Holstein Friesian cows (mean body weight:660 ± 42.9 kg) were used to investigate the effect of soybean meal (SBM) supplementation on voluntary rice straw (RS) intake, feed particle size reduction, and passage kinetics in the rumen. They were allocated to two dietary treatments: RS alone or RS supplemented with SBM. Voluntary dry matter intake of RS and total tract fiber digestibility was increased by SBM supplementation (p < 0.05). Supplementation with SBM decreased rumination time per dietary dry matter (DM) and neutral detergent fiber (NDFom) intake (p < 0.01). Particle size distribution in the rumen and total ruminal NDFom digesta weights were not affected by SBM supplementation. However, the disappearance rates of total digesta and large and small particles from the rumen were increased by SBM supplementation (p < 0.01). Moreover, SBM supplementation increased the rate of size reduction in ruminal particles (p < 0.05). In situ disappearance of DM and NDFom of RS in the rumen was greater in SBM-supplemented cows than in nonsupplemented cows (p < 0.05). This study clearly showed that increased ruminal RS particle size reduction, passage, and fermentation due to SBM supplementation accelerated the RS particle clearance from the rumen and resulted in increased voluntary RS intake of dairy cows.

Horses achieve a higher degree of particle size reduction through ingestive mastication than functional ruminants. We characterized mastication using chew-monitoring halters (RumiWatch) in six domestic horses, cattle, and Bactrian camels each. All animals were offered grass hay of the same batch for 15 min. In cattle and camels, measurements were continued after eating until rumination was observed. Except for one horse, 96% of the horses' ingestive mastication data were identified as "rumination" by the proprietary RumiWatch algorithm, whereas ingestion and rumination by cattle and camels were mostly classified correctly. There were no systematic differences between cattle and camels. In cattle and camels, ingestive mastication was less regular than rumination, indicated by significantly higher standard deviations of chewing peak intervals, peak heights, and peak breadths in intraindividual comparisons. The average standard deviations of these measures were lower in horses than in cattle and camel ingestive mastication, indicating a more consistent chewing pattern in horses. Horse values were similar to those of rumination mastication, suggesting equally regular chewing motions. Regular, rhythmic chewing represents a common feature of horses and functional ruminants, but the less uniform ingestive mastication in functional ruminants represents a deviating pattern, the adaptive value of which remains unclear. In particular, it does not appear to promote a higher ingestion rate. A potential cause may be the avoidance of high tooth wear rates by delaying a more regular, systematic mastication until ingesta has been softened and the grit has been washed off in the forestomach.

A top-down approach, i.e., creating small particles by mechanical force starting from bulk materials, probably presents the most logical approach to particle size reduction and, therefore, top-down techniques are among the first to achieve small particles. A new solvent-free, amazingly simple approach is reported, suitable to achieve nanoparticles and sub-micro particles.

Die Verwertung von Mauerwerkbruch als Rohstoff fur die erneute Produktion von Mauersteinen oder anderen Baustoffen erfordert sortenreine Materialfraktionen. Dazu ist der Aufschluss der einzelnen Materialien aus dem Verbundbaustoff erforderlich, um zunachst den gesuchten Wertstoff freizulegen und so die sich anschliesende Abtrennung von Fremd- und Storstoffen durch Sortierprozesse zu ermoglichen. Der Aufschluss geschieht i. d. R. durch eine Zerkleinerung. In der vorliegenden Veroffentlichung wird uber Zerkleinerungsversuche an Musterwanden berichtet, die aus verschiedenen Wandbaustoffarten bestanden. An den Zerkleinerungsprodukten wurden die erreichte Partikelgrosenreduktion und der Aufschlussgrad untersucht. Recovery of Homogeneous Building Material Fractions from Masonry Construction. The application of masonry rubble as raw material for the further production of masonry blocks or other building materials requires homogeneous material fractions. This necessitates disintegration of the individual components of the composite masonry material, so that the recyclable fraction is exposed and can be separated from impurities and contaminants through a further sorting process. Typically, this disintegration is accomplished through crushing. The following paper describes the results of crushing trials undertaken on material from sample masonry walls of differing construction. Investigation of the products of the crushing process considered particle size reduction and the degree of disintegration.

Gas–solid fluidization has a wide range of industrial applications like catalytic reactions, combustion, gasification, etc. In a number of these applications, there is particle size reduction during the operation leading to severe entrainment and limitation of operating velocity. The various problems associated with particles of different sizes or changing particles sizes could be overcome by adopting tapered beds in fluidization operation. In the present investigation, the fluidization phenomenon in tapered beds has been critically assessed through experimental investigations using particles of different sizes and materials and wide range of apex angles of the vessels. The effect of particle size and apex angle on the fluidization behaviour is clearly brought out which has not been reported so far in literature. The importance of compressive force existing in tapered beds is highlighted. In addition, correlations for all hydrodynamic characteristics, viz. critical fluidization velocity, minimum velocity for full fluidization, maximum velocity for defluidization, peak pressure drop, fluctuation ratio, compressive force, and hysteresis have been developed some of which are proposed for the first time. La fluidisation gaz-solide revet un vaste eventail d'applications industrielles comme les reactions catalytiques, la combustion, la gazeification, etc. Pour un certain nombre deces applications, il y a une reduction granulometrique durant l'activite menant a un entrainement eta une limitation intenses de la vitesse de fonctionnement. Les divers problemes lies aux particules de dimensions differentes ou aux dimensions de particules changeantes pourraient etre surmontesen adoptant les lits coniques dans les activites de fluidisation. Dans le cadre de la presente etude, lephenomene de fluidisation dans les lits coniques a ete evalue de facon critique au moyen deverifications experimentales employant des particules de dimensions et de matieres differentes et d'un vaste eventail d'angles de sommet de fluidiseurs. L'effet de la dimension des particules et del'angle des sommets sur le comportement de la fluidisation est nettement mis en evidence, ce quin'a pas ete souleve a venir jusqu'ici dans la documentation. L'importance de la force decompression qui existe dans les lits coniques est mise en evidence. De plus, les correlations relativement a l'ensemble des caracteristiques hydrodynamiques, c.-a-d. la vitesse de fluidisation critique, la vitesse minimale de fluidisation complete, la vitesse maximale de defluidisation, la chute des pics de pression, le taux de fluctuation, la force de compression et l'hysteresis, ont ete elaborees, certaines d'entre elles etant avancees pour la premiere fois.

Voluntary intake potential of a forage crop is generally considered to be the most important feed characteristic regulating animal performance. Efforts to develop forage crops with reduced neutral detergent fi ber (NDF) concentration are associated with reduced plant fi tness, prompting the development of alternative approaches to improve intake, such as particle-size reduction index (PSRI). The objective of this research was to characterize correlated selection responses of four fi tness traits following divergent selection for PSRI. Twelve smooth bromegrass (Bromus inermis Leyss.) populations (four base populations and their Cycle-1 high-PSRI and Cycle-1 low-PSRI progeny) were evaluated for forage yield, ground cover, seed yield, and lodging. Divergent selection for PSRI resulted in a negative change in forage yield, ranging from −0.097 to −0.379 Mg ha –1 cycle –1 across the four base populations. Pleiotropy or very tight linkage between loci controlling forage yield and PSRI accounted for only about half of the variation due to selection. The greater inconsistency of forage yield selection responses across the four populations, the lesser proportion of forage yield sum of squares attributable to divergence (pleiotropy or tight linkage), and the reduced magnitude of linear selection responses for PSRI compared to NDF suggest that PSRI may be a more effective selection criterion for improving intake potential of smooth bromegrass.

BACKGROUND: Previous findings demonstrated that particle size reduction of insoluble fibre materials (i.e. starfruit insoluble fibre-rich fraction and cellulose) to micro-sizes effectively enhanced their physicochemical properties, which provided clues to their physiological functions. The aim of the present study was to investigate the effects of particle size reduction of these insoluble fibres by micron technology on indices of bowel health. RESULTS: Feeding of the micronised fibres (9.68–14.3 µm), especially those prepared by high-pressure micronisation, effectively (P < 0.05) improved various caecal and faecal indices, such as decreasing the caecal ammonia concentration (by 20.0–30.0%), increasing the faecal output (135–150%) and moisture content (143–157%) and lowering the activities of undesired β-D-glucosidase (by 39.2–43.6%) and β-D-glucuronidase (by 71.4–77.5%) in faeces of hamsters. Relationships between physicochemical properties and physiological functions of the micronised fibres were considered. The results also demonstrated that the type, processing and related particle size of insoluble fibres were important factors affecting their physicochemical properties and physiological functions. CONCLUSION: The consumption of micronised insoluble fibres at 5% level might exert a favourable effect on improving various caecal and faecal indices. The results of this study provide some hints on potential applications of micron technology in the food industry. Copyright © 2007 Society of Chemical Industry

The synthesis of Pb(Mg 1/3 Nb 2/3 )O 3 (PMN) with high-energy milling was studied by X-ray powder diffraction (XRD) using the Rietveld-refinement method. The results are discussed in terms of the qualitative and quantitative composition of the crystalline and amorphous phases as a function of milling time. The mechano-synthesis of PbO, Nb 2 O 5 , and MgO leads to the formation of perovskite PMN. In the initial stage of milling, particle size reduction and a high degree of amorphization were observed, together with the simultaneous formation of perovskite and pyrochlore-type structures. A mechanism for the formation of PMN by the mechano-synthesis route is proposed.

Casein precipitated with high pressure-CO2 (CO2CAS) has unique properties compared to commercial acid-precipitated casein. CO2CAS is less water-soluble and films made from it are less susceptible to high humidity environments; however, the films are also opaque and hazy. The appearance of CO2CAS films is important especially if applied as a food coating. To improve the appearance properties, the particle size of CO2CAS film plasticized with glycerol was reduced. The effect of protein particle size reduction on tensile properties, water vapor permeability (WVP), and gloss was studied using ASTM methodology. As particle size of the CO2CAS was reduced from 126 μm to 111 μm, tensile strength and modulus of the films increased, while WVP decreased. With the same particle reduction, gloss increased from 55.3 gloss units on average to 73 gloss units, but films were still hazy. With a particle size less than 86 μm, CO2CAS films were glossy and transparent, however, tensile strength decreased and WVP increased. Depending on desired application, the properties of CO2CAS films can be optimized by changing particle size.

The past 5 years have seen the commercialization of two recombinant protein products from transgenic plants, and many recombinant therapeutic proteins produced in plants are currently undergoing development. The emergence of plants as an alternative production host has brought new challenges and opportunities to downstream processing efforts. Plant hosts contain a unique set of matrix contaminants (proteins, oils, phenolic compounds, etc.) that must be removed during purification of the target protein. Furthermore, plant solids, which require early removal after extraction, are generally in higher concentration, wider in size range, and denser than traditional bacterial and mammalian cell culture debris. At the same time, there remains the desire to incorporate highly selective and integrative separation technologies (those capable of performing multiple tasks) during the purification process from plant material. The general plant processing and purification scheme consists of isolation of the plant tissue containing the recombinant protein, fractionation of the tissue along with particle size reduction, extraction of the target protein into an aqueous medium, clarification of the crude extract, and finally purification of the product. Each of these areas will be discussed here, focusing on what has been learned and where potential concerns remain. We also present details of how the choice of plant host, along with location within the plant for targeting the recombinant protein, can play an important role in the ultimate ease of recovery and the emergence of regulations governing plant hosts. Major emphasis is placed on three crops, canola, corn, and soy, with brief discussions of tobacco and rice.

High-intensity ultrasonic treatment of MeOH/H2O, IPA/H2O, EtOH or H2O suspensions of C-14 labeled and unlabeled pharmaceuticals successfully reduced the average particle diameter from a range of 8–260 to 4–15 µm as determined by optical microscopy. Copyright © 2004 John Wiley & Sons, Ltd.

A new method for characterizing the grinding characteristics of wheat grain is described. A micromill was designed for this purpose and equipped with on-line torque transducers to obtain accurate measurements of mechanical energy consumption during milling. This micromill can be used for testing the milling performance of small quantities of grain (100 g). It can distinguish between different types of wheat grain (soft wheat, hard wheat, durum wheat) on the basis of total specific energy during milling. Wheat characterization can be enhanced by taking particle sizes of the milled products into account. A milling index based on energy consumption and particle size reduction was developed to characterize wheat behavior during milling. This index had a high discriminatory potential, ranging from 100 kJ/kg for soft wheat flour to 600 kJ/kg for durum wheat flour. This micromill directly measures the grinding resistance of wheat kernels as a function of both the kernel hardness and vitreousness, contra...

Planetary ball mills are well known and used for particle size reduction on laboratory and pilot scales for decades while during the last few years the application of planetary ball mills has extended to mechanochemical approaches. Processes inside planetary ball mills are complex and strongly depend on the processed material and synthesis and, thus, the optimum milling conditions have to be assessed for each individual system. The present review focuses on the insight into several parameters like properties of grinding balls, the filling ratio or revolution speed. It gives examples of the aspects of grinding and illustrates some general guidelines to follow for modelling processes in planetary ball mills in terms of refinement, synthesis' yield and contamination from wear. The amount of energy transferred from the milling tools to the powder is significant and hardly measurable for processes in planetary ball mills. Thus numerical simulations based on a discrete-element-method are used to describe the energy transfer to give an adequate description of the process by correlation with experiments. The simulations illustrate the effect of the geometry of planetary ball mills on the energy entry. In addition the imaging of motion patterns inside a planetary ball mill from simulations and video recordings is shown.

In Europe, the extraction of starch from wrinkled peas is interesting in economic terms as it would enable a high amylose starch to be isolated from a native raw material. Extraction of starch from wrinkled peas with a high yield and purity does, however, make high demands on the mechanical processing of the raw material. For this reason, studies were carried out with the aim of developing processing parameters with which a suitable disintegration of the raw material could be achieved. This included an investigation into the influence of the way the raw material was prepared and its disintegration. Based on the results of these investigations, a process was developed in which wrinkled peas were steeped in warm water, then hulled using rubber rollers in order to separate the husks from the cotyledons. This was followed by gentle particle size reduction of the cotelydons and high-pressure disintegration of the screened out protein/starch fraction suspended in the process water. This process enabled up to 89% of the starch present in the wrinkled peas to be extracted, with a residual protein content of around 1%, and by-product fractions containing a high concentration of the constituent characterising them to be obtained. Gewinnung amylosereicher Starke aus Markerbsen. Die Gewinnung von Starke aus Markerbsen ist in Europa deshalb von wirtschaftlichem Interesse, weil dadurch eine aus heimischen Rohstoffen isolierbare Starke mit hohem Amylosegehalt zur Verfugung stunde. Die industrielle Gewinnung der Starke aus Markerbsen mit hoher Ausbeute und Reinheit stellt jedoch sehr hohe Anforderungen an die mechanische Aufarbeitung des Rohstoffs. Deshalb wurden Versuche mit der Zielsetzung durchgefuhrt, Verfahrensparameter auszuarbeiten, mit welchen ein geeigneter Rohstoffaufschlus erreicht werden kann. Dazu wurde der Einflus der Vorbereitung des Rohstoffs und seines Aufschlusses untersucht. Auf der Grundlage der dabei gewonnenen Ergebnisse wurde ein Verfahren entwickelt, das auf der Quellung von Markerbsen in warmem Wasser, nachfolgende Schalung der Erbsen zur Abtrennung der Schalen von den Kotyledonen zwischen Gummiwalzen, schonender Zerkleinerung der Kotyledonen und Hochdruckaufschlus der im Prozeswasser suspendierten abgesiebten Protein-Starke-Fraktion beruht. Durch Anwendung dieses Verfahrens war es moglich, bis zu 89% der im Rohstoff enthaltenen Starke mit einem Restproteingehalt von etwa 1% aus den Markerbsen zu extrahieren und Nebenproduktfraktionen zu erhalten, in denen der sie charakterisierende Inhaltsstoff in hoher Konzentration enthalten war.

Skillful selection and evaluation of pigments for use in PVC compositions demands careful recognition and interpretation of side effects. These include possible interfering effects due to additives such as lubricants, heat and light stabilizers, U.V. screeners, etc. In addition, it has been observed that pigments can chemically react with polymers (PVC included) initiating degradative processes or catalyzing oxidation of PVC or its additives. Other changes affecting pigment performance in PVC include its solvation by the polymer at high processing temperatures and particle size reduction by abrasion during high intensive premixing. Also, in applications where amount of heat build-up of dark vinyls due to light absorption is important, inorganic pigments are shown to be superior to their organic counterparts. However, care in controlling processing temperatures to preclude polymer-pigment reactions needs to be exercised when inorganic pigments such as iron oxide, cadmium yellow pigments, and any other mixed metal oxides are evaluated, for use in PVC compounds.

To investigate links between the anatomy of grass leaves and their resistance to breakdown in the rumen, leaf blades of the tropical grass, green panic (Panicum maximum var, trichoglume), and the temperate grass, Italian ryegrass (Lolium multiflorum), were chopped into 50 mm lengths and fed fresh to cattle. Particle size reduction of the chewed feed was studied immediately after eating and after digestion in nylon bags in the rumen for 6, 12, 24, 48, 96 h and 3 weeks. The lengths of fibre elements, separated into groups of different diameters, were measured on samples digested for 96 h. The process of tissue breakdown was studied using light and electron microscopy. Green panic leaves had twice the cross-sectional area of thick-walled tissues, a higher vascular bundle frequency per unit leaf width, and less, but more densely packed mesophyll, than did the ryegrass leaves. Despite the contribution of these characteristics to greater leaf rigidity, green panic was broken down to a greater degree by chewing than was ryegrass. During digestion, width reduction of the chewed leaf particles was faster in ryegrass than in green panic because of two anatomical features: (i) the straight-walled intercostal cells of the epidermis in ryegrass were easily separated allowing the epidermis to split, whereas the sinuous walls in green panic were resistant to splitting, and (ii) the epidermis of ryegrass was linked to the vascular bundles by thin-walled mesophyll cells and was shed when these were digested, whereas in green panic the linkage was via thick-walled bundle sheath cells causing the epidermis to remain attached for much longer. Ryegrass leaf was reduced to isolated fibres within 24 h digestion; this process took >48 h in green panic. These fibres all had a high resistance to length reduction by digestion irrespective of their anatomical or species origin. Even after 3 weeks in the rumen there was little digestive disruption to the longitudinal walls of these fibres. The isolated vascular fibres of ryegrass were smooth-surfaced in contrast to those of green panic which were rough owing to attached undigested bundle sheath cells and jagged, broken sections of epidermis; this could influence ease of separation of particles from the digesta mass and flow from the rumen. Anatomical differences between these grasses were, therefore, important in the rate of width reduction of leaf particles during digestion and for the characteristics of the isolated fibre, but not for length reduction of particles during digestion

The disperse dyes have come to be applied to a very large number and variety of fibres and have therefore achieved an importance which is probably greater than the weights used would suggest. They were the first type to be applied directly to a fibre from an insoluble suspension. Their preparation includes a process of particle size reduction and often subsequent drying, both in the presence of a dispersing agent. The mechanism of dyeing with them would seem to entail their passing from suspension through solution on to the fibre, to which they become attached by non-polar forces. The colouring matters used in the preparation of disperse dyes belong mainly to three chemical groups. The connection between dyeing and fastness properties on the one hand and chemical constitution on the other is in general indefinite. However, the best fastnesses are obtained by moving in the direction of greater molecular complexity, but this unfortunately is accompanied by a reduction in dyeing power. The introduction in recent years of the man-made fibres has accelerated the development of new application methods, and these are assisting the dyer to utilise these more complex dyes. This tendency emphasises that the achievement of better fastness with disperse dyes will require, as with other dyeing classes, a close understanding between, and the combined efforts of, both those working on the elaboration of new dye structures and those whose interests lie in one or other aspects of dye application.