Volume Of Wool Research Articles

Современное состояние отрасли животноводства Волгоградского Заволжья

Дана оценка современному состоянию отрасли животноводства Заволжья в границах Волгоградской области в 6 районах. Установлен прирост поголовья крупного рогатого скота (КРС) в 4 районах. Наибольшая численность поголовья КРС в Заволжье сосредоточена в хозяйствах населения и КФХ. Наибольшее поголовье овец и коз в районах Заволжья выявлено в Палласовском районе — 153,8 тыс. голов. Рост поголовья овец и коз отмечен в 5 районах. Наибольшее количество поголовья лошадей в хозяйствах всех категорий зарегистрировано в Палласовском (2,8 тыс. голов) и Ленинском (1,1 тыс. голов) районах. Отмечен большой процент поголовья лошадей в хозяйствах всех категорий в Заволжье в общем поголовье лошадей Волгоградской области — 51,15 %. Наибольшее производство КРС на убой в хозяйствах всех категорий выявлено в Палласовском районе — 5225 т. Основное производство молока сосредоточено в хозяйствах населения, особенно в Ленинском, Палласовском и Быковском районах. В Заволжье выращивают около 1/2 поголовья овец и коз на убой и производится около 1/2 объема шерсти в хозяйствах всех категорий от общего производства области.

The use of wool as fiber-reinforcement in cement-based mortar

Fiber-reinforced cementitious mortars are widely used in the construction industry. Indeed, the fracture toughness in tension increases with the volume and the aspect ratio (i.e., the ratio between length and diameter) of the fibers, which are generally made with polymeric (e.g., polyethylene, polyvinylchloride, etc.) or inorganic (e.g., glass, carbon, etc.) materials, or with steel. Also vegetal fibers, such as bamboo and hemp, have been used in the last decades to reinforce mortars. Besides, with the aim of introducing animal fibers, the use of wool as fiber-reinforcement is investigated for the first time in the present paper. According to UNI EN 196-1-2006, three point bending tests have been performed on small beams made, respectively, with plain mortar, and mortar reinforced with 1% in volume of wool. To compare the performances with mortars containing vegetal fibers, also beams reinforced with hemp have been tested. In some tests, wool and hemp are previously treated with atmospheric plasma in order to modify the nano-metric properties of the fiber surface. As a result, both the flexural strength and the ductility increase when wool, treated or not, is added to cementitious mortars. Similarly to hemp, wool does improve the mechanical and ecological performances of the mortars, and creates a link between textile and construction markets.

A Rapid Method for the Measurement of Wool Volume and Density

The volume of wool was measured with a gas pycnometer, and its density was calculated. Samples with a high degree of medullation, low degree of medullation, and no medullation were measured at five relative humidities and over a range of masses. The procedure adopted required a sample mass of between 2 and 10 g and used the fourth sequential measurement of volume to calculate density at 65% relative humidity and 20°C. The total measurement time per sample was 10 minutes. Density decreased as the degree of medullation increased. Non-medullated wools had a density of 1.307 g/cm3.

Effects of abomasal protein and energy supply on wool growth in Merino sheep

The relative importance for wool growth of energy-yielding nutrients compared with amino acids required for incorporation into wool proteins was assessed in an experiment in which most nutrients were supplied via the abomasum. Nine nutritional treatments, providing three levels of protein (53, 99 and 145 g/day) to the intestines at three levels of energy (5.2, 7.5 and 9.7 MJ/day), were given to 12 Merino sheep during three consecutive periods of 3 weeks in a balanced lattice design. Abomasal nutrients consisted of varying proportions of casein, whole milk, glucose and glycerol. There was a large effect of protein supply on all components of wool growth, but there was no significant effect of energy. There was a significant interaction between the effects of protein and energy supply on diameter, length growth rate and volume of wool, but it was small relative to the main effect of protein. Extra energy appeared to enhance wool growth at the highest level of protein but reduce it at the lowest level of protein. The concentration of urea, cystine, methionine and other essential amino acids in plasma increased with protein level. Increasing energy supply reduced the concentration of urea and essential amino acids in plasma but not that of cystine or methionine. The experiment confirmed the major role of amino acid supply in controlling wool growth but indicated that there may be a small interaction with energy supply.

Effects of the infusion of amino acids into the abomasum of sheep, with emphasis on the relative value of methionine, cysteine and homocysteine for wool growth

SUMMARYMerino sheep were given abomasal infusions of various amino acids or mixtures of amino acids. Effects on wool growth were measured using autoradiography or a clipping procedure and changes in the concentration of amino acids in plasma were measured in some experiments.Mixtures of five (28 g/day) or ten (45 g/day) essential amino acids (both mixtures containing 3 g methionine) stimulated wool growth of sheep receiving a maintenance ration; on average, the volume of wool grown increased 48% and 86%, respectively. When cysteine completely replaced methionine in these mixtures, wool growth was markedly reduced, but two-thirds of the methionine could be replaced by cysteine without affecting wool growth. Homocysteine was partially effective in replacing methionine and, when supplemented with betaine, folic acid and vitamin B12, the mixture was still significantly inferior to that containing methionine. In contrast, abomasal supplements of methionine or homocysteine alone were equivalent as supplements for wool growth. The results indicated a specific role for methionine in the control of wool growth, other than the provision of cysteine. This role was postulated to be related to some function of S-adenosylmethionine.Infusion often essential amino acids caused appreciable increases in the concentrations of cystine, methionine, cystathionine and taurine in plasma; total essential amino acids increased threefold whereas nonessential amino acids decreased in concentration. The replacement of methionine in the infusion by cysteine or homocysteine significantly altered the concentration of cystine, methionine and cystathionine in plasma.Evidence was obtained that the adverse effects on wool growth of high abomasal doses of methionine (10g/day) could not be reduced or prevented by provision of additional glycine and were not related to the supposed toxic effects of 3-methylthiopropionic acid, a metabolite of the transamination pathway.

Minimum Volume Pressing of Greasy Wool

Greasy wool preheated to 90°C can be compressed in one press minute to over 1000 kg/m3 using about one-third of the pressure needed at ambient temperatures, and then cooled out-of-press to give long-term stability of compressed density similar to that obtained by maintaining the pressure during in-press heating and cooling. Minimum total volume, the actual volume of wool plus contaminants with air excluded, can almost be achieved at pressures below 5 MPa. At higher pressures, product volume is reduced by the volume of extra grease squeezed out for recovery, resulting in a higher wool yield product of lower weight.

The effects of exposure in Blackface sheep with particular reference to the role of the fleece

1. The effect of shelter from winter conditions was studied in terms of body-weight change of dry sheep individually fed a maintenance ration. In 2 years, one a mild and the other a hard winter, the exposed group lost weight relative to the sheltered group.2. Within the treatments attempts were made to relate individual weight loss to a variety of fleece components. These results were not conclusive, but they suggest that such components as depth of wool and weight or volume of wool per unit area of skin have some effect in reducing weight loss under climatic stress conditions.3. A method of measuring the insulation provided by the fleece in dry environmental conditions was developed. It was shown that exposure to moderate winds increased the heat flow by between three and five times. The results again suggested that significant differences in insulation could be found between sheep within a breed. It was not possible to demonstrate the overwhelming importance of any single fleece component.

Sorption of liquids by wool. Part III. Accessibility of wool to sorbates

Equations are derived which relate the pore volume and the volume of pores accessible to sorbate with the constitutive volume vAA, the electrostriction of sorbate by the charged groups of wool vE, and the volume contraction of sorbate in the neighborhood of nonpolar side chains vNP. The pore volume and the volume of pores accessible to sorbate are calculated by use of values of vAA and vE estimated from theory and assuming vNP = 0. The percentage of pores accessible to water increases from 55 to 78 as the pH is decreased from 7 to 2, due to a reversible change which is probably analogous to the reversible unfolding of the serum albumins. Supercontraction in LiBr produces a decrease in the specific volume of wool in n-hexane, the partial specific volume in water, the pore volume, and the volume of pores inaccessible to water. Since analogous changes occur on denaturation of soluble proteins it is proposed that the crystalline regions (containing α-helices) are less dense than the amorphous regions (containing random coils). This is probably due to poorer packing of the diverse side chains in the crystalline regions than in the amorphous regions, since in the latter the chains should be able to bend to accommodate bulky side chains. All evidence available on the accessibility of wool to various sorbates is summarized. Although it is not yet possible to be dogmatic, it is clear that the weight of evidence suggests that wool is approximately equally accessible to water and the lower alcohols.

Mineral Wool Industry of the United States

M / INERAL wool is a fibrous mineral material, resembling XV _ _ loose wool or cotton in appearance, which is made by blowing a jet of air or steam through molten slag. It consists of fine, interlaced fibers composed principally of silicates of calcium and aluminum together with other minor constituents. Because of the high percentage of dead air space in a given volume of wool, it is used extensively for sound and heat insulation. Mineral wool may be divided into three types according to the raw material from which it is made. These three types are rock wool, slag wool, and glass wool. Rock wool is made, in most cases, from natural siliceous limestones or calcareous shales. In some cases rock wool is made from limestone mixed with clay or shale in the proper proportions. Slag wool is made from blast furnace slag with or without the addition of limestone to temper the charge. Iron, copper, and lead slags are most commonly used in the production of slag wool. Glass wool is made from commercial glass batches. The principal materials which go into the glass batch are silica sand, lime, and soda ash.