The C/C-SiC composites have relatively high stationary friction coefficient. The sample whose preform density is1.47g/cm3 is suitable to be used as braking materials.

(2) The change trend of wood density along radial direction for two species were same: mature wood >juvenile wood > overmature wood. The difference in three density between juvenile and mature Larch wood as well as between mature wood and overmature wood reached 0.01 level of significance.

This means it is time for thinning. It is not reasonable to calaulate the thinning strength by original density, so it is determined by the different amounts of remaining trees. During production we check the number of remaining trees with a tabled on the improved B. E.

The effects of the initial stoichiometry, initial density, particle size of silicon, and initial temperature on the spin combustion process were studied mainly in Ni-Si system. In Ti-Ni system, the effects of preheating temperature and initial stoichiometry of compact on combustion process and mode were studied.

The C/C-SiC composites have relatively high stationary friction coefficient. The sample whose preform density is 1.47g/cm3 is suitable to be used as braking materials.

The physical reason for such a sharp change in the magnetoabsorption coefficient as compared with the expected result for the ordinary density of states in a quantizing magnetic field is that the electronic excitations are quasi-one-dimensional.

The iterative scheme shows how, in practice, density estimation from indirect observations may be performed by simply correcting an appropriate ordinary density estimator.

Instead, the liquid plasma model simply requires a very ordinary density throughout the body of the Sun.

The growth exponent for the minority is related to its absolute density and temperature because of its small density.

We present systematic studies on the absolute density of hydrogen cluster beams produced by using Laval-nozzles.

It is assumed that, for those prey animals whose percentage in the total prey of a predator is fairly high, the percentage proportionally approximates the real fluctuations in their (absolute) density.

Our results clearly demonstrate that absolute density is a poor predictor of roe deer performance and supports the view that habitat quality has an overwhelming importance for determining fawn body mass in roe deer populations.

In three patients with chronic obstructive pulmonary disease and in one healthy subject, absolute density of selected lung regions was measured in the supine position by the Compton scatter technique.

The total work of compaction of powders, from zero strain(ε= 0) to in-finite strain (ε= ∞), is derived in this paper to be: a_(total)= Mw (1/d_0-1/d_m) Γ(m + 1)where M is the modulus of compaction of powder, w is the weight of powder,d_0 is the initial density of powder, d_m is the theoretical density of densemetal, m is the index of non-linearity and Γ(m + 1) is the gamma functionof (m + 1). Γ(m + 1) = ∫_0~∞ e~(-8)ε~mdεwhere ε is the strain of compaction, ε=ln((d_m-d_0)d)/((d_m-d)d_0)and d is the green density...

The total work of compaction of powders, from zero strain(ε= 0) to in-finite strain (ε= ∞), is derived in this paper to be: a_(total)= Mw (1/d_0-1/d_m) Γ(m + 1)where M is the modulus of compaction of powder, w is the weight of powder,d_0 is the initial density of powder, d_m is the theoretical density of densemetal, m is the index of non-linearity and Γ(m + 1) is the gamma functionof (m + 1). Γ(m + 1) = ∫_0~∞ e~(-8)ε~mdεwhere ε is the strain of compaction, ε=ln((d_m-d_0)d)/((d_m-d)d_0)and d is the green density of powder compact.The actual work of compaction of powders from ε_1 to ε_2 is derived to be: a = Mw (1/d_0-1/d_m)∫ε_1ε~2 e~(-ε)ε~mdεwhere ∫_(ε_1)~(ε_2)e~(-ε)ε~mdεis the incomplete gamma function of (m + 1), the numer-ical value of which can be evaluated by computers. Examples of calculations for the work of compaction on tungsten powderare given and tabulated.

The principle of density method for determining the creep damage is based on the creep occuring in metal in the form of voids thus reducing the density of rhe metal. The first density of 12Cr1MoV steel relates to the early stage structure of the initial pipe. The form, dimension and quantity of voids are observed, and the change of density ratio(expressed in percentage) is obtained in different stage of creep. Then the remainder of the service life of the pipe is estmated. If the ratio exceeds 0.2 percent, the...

The principle of density method for determining the creep damage is based on the creep occuring in metal in the form of voids thus reducing the density of rhe metal. The first density of 12Cr1MoV steel relates to the early stage structure of the initial pipe. The form, dimension and quantity of voids are observed, and the change of density ratio(expressed in percentage) is obtained in different stage of creep. Then the remainder of the service life of the pipe is estmated. If the ratio exceeds 0.2 percent, the pipe should be changed. This method is simple and efficicient.

Under an ideal roll-condition,the friction-coefficient of dense metals can be calculated by the formula as μ=a/2[1-(4S_nh/Δh)~(1/2) ]~(-1) ,where a is the critical angle of nip,S_n the forward slip determined experimentally and Δh the rolling reduction.Based on the mass constancy of the porous metal under deformation,in this paper,a modified formula for calculating the μ has been proposed,given by μ=a/2[1-(4(S_n+1-K)/KΔh)~(1/2) ]~(-1) ,where K is a modified index taking dinsification into account.The latter...

Under an ideal roll-condition,the friction-coefficient of dense metals can be calculated by the formula as μ=a/2[1-(4S_nh/Δh)~(1/2) ]~(-1) ,where a is the critical angle of nip,S_n the forward slip determined experimentally and Δh the rolling reduction.Based on the mass constancy of the porous metal under deformation,in this paper,a modified formula for calculating the μ has been proposed,given by μ=a/2[1-(4(S_n+1-K)/KΔh)~(1/2) ]~(-1) ,where K is a modified index taking dinsification into account.The latter formula may be considered as an universal for it would be the same as the former(here K exactly becomes 1) when used to the dense metals.The values of forward slip were measured experimentally on copper powder