The binding of sodium and potassium into cement paste influences the performance of concrete: for example, alkali balances between solid and paste constituents and pore fluid affect the potential for alkali aggregates reaction. However, quantification of the binding potential into paste solids has proven to be difficult, although much empirical data are available from pore fluid analyses. In this study, single-phase homogeneous C-S-H phases have been prepared at Ca: Si molar ratios (C/S) of 1.8, 1.6, 1.3, 1.0 and 0.8 and reacted with four alkali hydroxide concentrations, both NaOH and KOH, between 10 and 300 mM. A steady-state alkali partition is attained in less than 4d at 20°C by flame emission spectroscopy and the ξ potential of C-S-H and C-A-S-H gel unreacted and reacted with alkali hydroxide are measured. The results indicate：alkali binding into the C-S-H and C-A-S-H gel improves as its C/S decreases；Al3+ has been introduced to form C-A-S-H gels, and the influence of Al3+ on alkali sorption properties was determined: the replacement of Si4+ by Al3+ and Na+ or k+ markedly increases alkali binding and decreases the ξ potential of gel；the more Ca:Si ratio，the less alkali binding, the more ξ potential of gel.

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Two plasma channels, corresponding to a slow capillary discharge and a fast capillary discharge plasma, are investigated numerically. A long-lifetime parabolic plasma channel is formed in the slow capillary discharge channel. Its radial density profile is determined by the energy balance between Ohmic heating and thermal conduction, together with force balance. The profile and the on-axis density value vary only weakly with the peak value of the slow discharge current (300-600 A). A rather dynamic plasma channel is formed under the compression by a magnetic piston in the fast capillary discharge channel. In a narrow time window of the order of nanoseconds a suitable hollow relatively low density channel is reached, followed by a shock-dominated rebound phase. The on-axis density minimum features of these two channels make both of them suitable guiding channels for the laser wakefield accelerators. In particular, a low-density channel (n e ∼ 5 × 10 16 cm −3) formed in the fast capillary discharge is in favor of controlled beam injection, but requires precise timing, while the slow capillary discharge is in essence steady. We discuss possible strategies for using them in a segmented approach.

Abstract-In this paper the AC power 50Hz power interference, we use IIR digital notch filter method for industrial frequency interference filter. From the design of IIR digital filter method proceed with, on the IIR digital notch filter simulation, the algorithm deduced, on the fixed-point DSP programming method and overflow handling problems made elaborate incisively, and in digital audio signal processing system has been applied.

Nano-ZnO sol solution was prepared by using Zn(CH3COO)2•2H2O as raw material and β-cyclodextrin (β-CD) was added into the sol, then cotton fabric was treaded with the sol by pad-dry-cure technique. Moreover, the fixation fastness of the composite sol on the fabric was improved by adding the adhesives. Based on the tests of anti-UV, photocatalysis, antibacterial and weight gain rate after adsorbing essence, the results showed that the treated cotton fabrics added with β-CD had better adsorbability to essence, anti-bacterial activity, photocatalytic degradation to formaldehyde and excellent anti-UV property.