Prediction of cracking within early-age concrete due to thermal, drying and creep behavior

To predict potential early-age cracking after concrete placing, a numerical simulation procedure has been completed based on a micromechanical model and empirical formulas on the property development of young concrete. The numerical model could account for the effects of hydration, moisture transport and creep. Environmental influences, such as removal of formworks, curing conditions and variations of surrounding temperature and relative humidity, have been investigated. In calculating stress field with age caused by these synthetic physical-mechanical processes, three-dimensional finite element and finite difference (3D-FE-FD) methods are combined together.     

Filling of dislocation levels in strong electric fields

The dependence of the filling factor for occupation of the energy levels of an edge dislocation by electrons on the external electric field is investigated theoretically. An analytical relation is derived for the filling factor. It is established that the dislocation filling factor decreases as the electric field is increased. Fiz. Tekh. Poluprovodn. 32, 36–37 (January 1998)     

The effect of linseed oil on the fatty acid composition of blood plasma low- and very low-density lipoproteins and cholesterol in diabetics]

Twenty patients with compensated diabetes mellitus of 10-15-year duration took polyunsaturated fatty acids omega-3 (30 g of flax oil a day) in addition to their routine food. This led to an insignificant lowering in total cholesterol and elevation of cholesterol in high density lipoproteins. A significant rise in the level of omega-3 polyunsaturated fatty acids in lipoproteins occurred in 6 patients only. Minor effect of the diet oil may be due to low delta-6-desaturic activity in the majority of the examinees. The findings point to necessity to use other sources of omega-3 acids in diet therapy of diabetics, fish oil, in particular.     

On the oxygen deficiency of high-T c Y1Ba2Cu3O7-µ ceramics

The role of oxygen deficiency in Y₁Ba₂Cu₃O_{7 ? μ} ceramics has been investigated by differential thermal analysis (DTA), differential thermogravimetry (DTG), linear thermal expansion (LTE), and by soft x-ray fluorescence spectroscopy (SXFS). The interdependence of the measured parameters and some of the stability criteria are discussed.     

Modeling the Combining Site of the Human Asialoglycoprotein Receptor

A model for the carbohydrate recognition domain (CRD) and combining site of the human asialoglycoprotein (ASGP) receptor has been computed on the basis of the close sequence homology with the mannose-binding lectin (MBP), whose three-dimensional structure in complex with a ligand has been determined by crystallographic methods (Weis, W.I.; Drickamer, K.; Hendrickson, W.A. Nature 1992, 360: 127). Within the limitations of modeling methods, the model is compatible with data on ligand binding of the family C-type lectins, of which the MBP and the ASGP receptor are members. The model derived can serve as a guide for designing site-directed mutagenesis experiments in order to further elucidate the origins of specificity of the ASGP receptor toward galactose. In particular, the model focuses attention on the possible role of position 207 (MBP sequence numbering) in promoting galactose binding.     

Calculation and design of vibrational mills

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 1, pp. 14–15, January, 1992.     

Optimal Design of the High-Power Plate and Grid Modulated HF Amplifier by High Modulation Levels

The optimal design of the high power plate and grid modulated selective amplifier is examined in this paper. For the analysis purposes, the linear model of constant plate current characteristics for HF power triode is applied. The carrier wave state of the unmodulated amplifier is chosen so to enable the realization of the high levels of modulation. The results are obtained immediateZy, and the estimated error is acceptable. The estimated characteristic values of this high power and high efficiency HF amplifier are shown in the corresponding diagrams.