Ionic liquid salt bridge with low solubility of water and stable liquid junction potential based on a mixture of a potential-determining salt and a highly hydrophobic ionic liquid

A new type of ionic liquid salt bridge (ILSB) based on a mixture of pentyltripropylammonium bis(pentafluoroethanesulfonyl)amide, [N(3335)(+)][C(2)C(2)N(-)], and heptadecafluorodecyltrioctylphosphonium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, [TOPH(+)][TFPB(-)], shows a stable phase-boundary potential (Δ(IL)(W)φ) between the ILSB and an aqueous solution of MCl (M = H(+), Li(+), Na(+), and K(+)) over the concentration range from 0.05 mM to 0.5 M with an averaged excursion in 1 h of ±0.3 mV. The reproducibility of Δ(IL)(W)φ is ±0.6 mV on average (95% confidence interval) in KCl solutions in this concentration range. The mixing of the two different types of salts not only increases the stability of the phase-boundary potential but provides us with more freedom in selecting potential-determining salts to design and customize ILSBs for different purposes.     

Predicting the degradation behavior of magnesium alloys with a diffusion-based theoretical model and in vitro corrosion testing

Magnesium alloys have shown great potential for their use in the medical device field, due to the promising biodegradability. However, it remains a challenge to characterize the degradation behavior of the Mg alloys in a quantitative manner. As such, controlling the degradation rate of the Mg alloys as per our needs is still hard, which greatly limits the practical application of the Mg alloys as a degradable biomaterial. This paper discussed a numerical model developed based on the diffusion theory, which can capture the experimental degradation behavior of the Mg alloys precisely. The numerical model is then implemented into a finite element scheme, where the model is calibrated with the data from our previous studies on the corrosion of the as-cast Mg-1Ca and the as-rolled Mg-3Ge binary alloys. The degradation behavior of a pin implant is predicted using the calibrated model to demonstrate the model’s capability. A standard flow is provided in a practical framework for obtaining the degradation behavior of any biomedical Mg alloys. This methodology was further verified via the comparison with enormous available experimental results. Lastly, the material parameters defined in this model were provided as a new kind of material property.     

Stefan problem in the theoretical model of the thermal interaction between a molten heat-liberating material and finite walls

An approximate analytical solution of the one-dimensional Stefan problem is obtained for a single finite wall with constant heat fluxes at the boundaries. The conjugate problem for a system of molten heat-liberating material with two walls is solved by the finite-difference method.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 51, No. 5, pp. 825–830, November, 1986.     

Correlations and effective potential in the ground state of a one-dimensional model for solid helium and deuterium

The ground-state energyE can be calculated exactly by the transfer-integral method if the total wave function is assumed to be a product of single-particle functions and nearest-neighbor correlation functionsf. The variation ofE with respect tof for fixed leads to a Schrödinger equation for the relative motion of two particles which is coupled to the transfer integral equation by an effective potential V. For the case of a Gaussian the optimalf, the one- and two-particle probability amplitudes, and other quantities are computed by iteration of the Schrödinger equation with the transfer integral equation until self-consistency is achieved. The minimum ofE as a function of the Gaussian width is obtained for different values of the lattice parameter. The shape of V andf is discussed. The self-consistentf describes both short- and long-range correlations.     

ZDQ-65型水电解装置氢分离洗涤塔爆炸及处理

分析了武钢氧气公司ZDQ - 6 5型中压水电解装置的氢分离洗涤塔 ,由于违章操作致使电解液循环中断 ,氢氧气体混合产生剧烈的化学爆炸伤人事故的经过、现场调查事故原因分析、事故处理和事故教训。     

Mathematical model of heat and mass transfer in a geothermal reservoir upon extraction of steam and water mixture

A mathematical model of heat and mass transfer in a geothermal reservoir saturated with steam and water mixture upon the extraction of heat carrier through a single well is considered. The exact solution of the time-independent and quasi-time-independent nonlinear problems is obtained. Typical water saturation, temperature, and pressure distributions around a well are shown. Conditions for the regimes of heat and mass transfer, the violation of which leads to the formation of a region saturated with either pure fluid of pure steam, are found. Parametric studies are performed.     

Photosensitized degradation in water of the phenolic pesticides bromoxynil and dichlorophen in the presence of riboflavin, as a model of their natural photodecomposition in the environment

Within the context of environmentally friendly methods for the elimination of surface-water pollutants, the photodegradation of the phenolic pesticides bromoxynil (BXN) and dichlorophen (DCP) under simulated natural conditions has been studied. The work was done in the presence of the visible-light absorber photosensitizer riboflavin (Rf), usually present in trace quantities in natural waters. Under aerobic conditions, an efficient photooxidation of both pesticides was observed. The relatively intricate photochemical mechanism involves pesticide and oxygen consumption and, to a lesser extent, Rf degradation. The kinetic and mechanistic study supports that both H(2)O(2) and singlet molecular oxygen, O(2)((1)Δ(g)), are involved in the process. Kinetic data for the O(2)((1)Δ(g))-mediated oxidation indicate that BXN and DCP are photodegraded with this species faster than the parent compound phenol, very frequently employed as a model for aquatic contaminants, likely due to their lower pK(a) values. This observation allows the design of phenolic pesticides with different photodegradation rates under environmental conditions.