The global and local conditions of uniqueness and the criteria excluding a possibility of bifurcation of the equilibrium state for large and small strains are derived. The conditions and criteria are derived analyzing the problem of uniqueness of solution of the basic incremental boundary problem of coupled generalized thermoplasticity. This paper is a continuation of some previous work, but contains new derivation of the global and local criteria excluding a possibility of bifurcation of the equilibrium state for a comparison body dependent on statically admissible fields of stress velocity. All the thermomechanical coupling effects, nonassociated laws of plastic flow and influence of plastic strains on thermoplastic properties of a body were taken into account in this work. Thus, the mathematical problem considered here is not a self-conjugated problem.

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Three Polish Merino wethers, fed hay and ground barley, were defaunated and then faunated with Eudiplodinium maggii only; with Eudiplodinium maggii and Entodinium caudatum or with both opryoscolecids and Dasytricha ruminantium. The total number of ciliates varied in the range of 16-403 x 10 3 /g rumen content depending on the experimental period. Total bacterial contributed to 12.7-19.6% DM of rumen digesta. The bacterial matter in two of three sheep was negatively influenced by Entodinium caudatum and Dasytricha ruminantium while the effect of Eudiplodinium maggii was positive. The establishment of ophryoscolecid ciliates in the rumen resulted in an increase in both CMC-ase and xylanase activities (P<0.01), while the appearance of Dasytricha ruminantium was accompanied by a decrease in xylanolytic activity. A positive relationship was found between the numbers of Eudiplodinium maggii and both CMC-ase and xylanase activities (P<0.05) irrespective of the presence or absence of other protozoa in the rumen. It was calculated that 8-38% of the activity of CMC-ase and 14-49% of xylanase in the rumen originated from Eudiplodinium maggii. The quantities of dry matter, ADF and NDF that disappeared from the rumen within 12 h after feeding were 0.62-0.83, 0.18-0.32 and 0.32-0.54 kg, respectively.Establishment of Eudiplodinium maggii in the rumen was accompanied by increased disappearance of DM, ADF and NDF in only one of three animals. A decrease in disappearance of DM, ADF and NDF was observed following the establishment of Dasytricha ruminantium in all three animals. The concentration of acetic, propionic and butyric acids was within the ranges of 5.25-7.94, 1.29-2.34 and 0.75-1.39 mM/100 ml of rumen fluid, respectively. Acetate and propionate were the lowest in the sheep with the established population of Eudiplodinium maggii, whereas butyrate, in animals with all three ciliate species in the rumen. The highest concentration of acetic acid was observed following establishment of both entodiniomorphid species, while that of butyrate, in sheep inoculated with Eudiplodinium maggii. The production rate of acetate, propionate and butyrate was 21.3-24.5, 4.7-6.6 and 2.8-5.6 μM/g rumen contents/h, respectively. Production of acetic acid was not influenced by protozoa. An increase in the production rate of butyrate at 4 h after feeding was found after establishment of Eudipoldinium maggii in the rumen. Appearance of Entodinium caudatum and Dasytricha ruminantium decreased the production of butyrate at 4 h after and propionate just before feeding, respectively.

The paper presents an aproximate analytic method for determination of the stored energy of plastic deformation during cold bending of metal tubes at bending machines. Calculations were performed for outer points of the tube layers subjected to tension and compression (the points of maximum strains). The percentage of stored energy related to the plastic strain work was determined and the results were presented in graphs. The influence and importance of the stored energy of plastic deformation on the service life of pipeline bends are discussed.

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The relations to calculate the maximum value of relative strains, which occur in a process of bending of tubes on benders, in stretched layers of tubes, are presented in this work on the basis of EU-Directive concerning production of pressure equipment. It has been shown that for large deformations that occur during bending of the pipes on knees, logarithmic strain measures (real) and relative strain measures give different values of the relative distribution of strain and different wall thicknesses in the bending zone. Reverse expressions were also derived to calculate the initial wall thickness of the tube to be bent, in order to obtain the desired wall thickness of knee after bending. Keywords EU-Directive • Required thicknesses of pipe elbows • Pipe bending processes • Relative and logarithmic measures of deformation • Required initial thickness of a bent tube

The in situ and mobile nylon bag methods were used to determine the effective degradability of dry matter, crude protein and starch in the rumen and the digestibility of undegraded protein and individual amino acids of various feeds in the small intestine of the cow. The tested feeds included rapeseed oilmeal obtained from six industrial oil mills, soyabean oilmeal, field peas (coloured flowered), peas, field beans, lupin, rye, triticale, wheat, barley, oats, and wheat, rye and barley bran. The chemical and amino acid composition of the rapeseed meals from different sources was similar, and effective protein degradability, calculated assuming k = 0.05, ranged from 62 to 70%. The effective protein degradability of oilmeals was lower than in the legume seeds and cereal grains. Among cereals, oats had the highest effective protein degradability (92%), the lowest was found in winter barley (75%). The disappearance of total N in the rumen from rapeseed meals was lower than of total amino acids; in the remaining feeds these values were similar. Glutamic acid and arginine were degraded to a greater extent than the remaining amino acids, regardless of the type of feed. Intestinal digestibilities of total N and amino acids of feeds that were less degradable in the rumen, were higher. Cereal starch was degraded in the rumen to a higher extent than starch in legume seeds.