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Ensuring the safe operation of large LNG storage tank projects under blast loads is very important. First, using LS-DYNA software, numerical simulations of air blast wave propagation are studied with the ALE algorithm and fluid-solid coupling theory. A new corrected formula for the peak overpressure is proposed based on the numerical results, and its accuracy is verified by comparing the numerical results with the empirical formula and test results. Then, a finite element model of a large LNG storage tank is built, assuming that the explosion source is located 10 m away from both the ground and the tank wall. This model is used to analyse the overpressure and dynamic response of the outer concrete tank and to predict the TNT equivalent quantity that the tank can withstand. The results show that the tank wall facing the burst loads is in a more dangerous state and that the principal tensile stress increases approximately linearly with increasing TNT equivalent quantity. When the TNT equivalent quantity reaches 2.5 t, concrete element failure occurs on the centre facing the explosions, and the outer tank structure is damaged. The conclusions can provide a reference for the blast-resistant design of large LNG storage tanks.

This paper investigates the effect of the multi-directional components of ground motion on an unanchored steel storage tank. Both the liquid sloshing effect and contact behavior between the foundation and tank are included in the study. A three-dimensional model for a foundation&ndash, structure&ndash, liquid system is numerically simulated using the finite element method. The Lagrange fluid finite element method (FEM) in ANSYS is used to consider the liquid&ndash, solid interaction. In the liquid&ndash, foundation interaction model, the contact and target elements are adapted to simulate the nonlinear uplift and slip effects between the tank and the foundation. Three earthquake ground motions are selected for evaluating the seismic behavior of the tank. Comparisons are made on the horizontal displacement, &ldquo, elephant-foot&rdquo, deformation, stress, base shear and moment, sloshing of the liquid, uplift, as well as slip behavior under the application of the unidirectional, bi-directional and tri-directional components. Under the selected ground motions, the horizontal bi-directional seismic component has great influence on the liquid sloshing in the tank studied in this paper. The vertical seismic component produces high compressive axial stress, and it also makes the uplift and slide of the tank bottom increase significantly. The applicability of this conclusion should be carefully considered when applied to other types of ground motion inputs.

To study the effects of alginic acid on the growth of vegetables, a pot experiment was conducted to study the effects of spraying alginic acid at different dilution folds on the growth and osmotic adjustment substance content of radish under cadmium stress condition. The results showed that the biomass, leaf length and leaf width of radish with 600, 900, 1200 and 1500 dilution folds alginic acid were higher than those of the control, while the soluble protein content, relative conductivity and malondialdehyde content of the radish were lower than those of the control. When the dilution factor of alginic acid is 600 dilution folds, the biomass, leaf length and leaf width of radish’s roots, root tubers, leaves and edible parts all reach the maximum. Increased by 19.39%, 35.27%, 19.74%, 29.44%, 22.11% and 14.01% compared with the control, respectively; the soluble protein content, relative conductivity and MDA content of radish reached the lowest, which were 38.76%, 29.86% and 35.61% lower than the control, respectively. Sprayed diluted alginic acid can promote the growth of radish, and the best dilution factor is 600 dilution folds.

The seismic response of the tank-fluid system considering soil-structure interaction is studied. A three-dimensional (3-D) finite element method (FEM) model of soil-pile-structure-fluid interaction system is built based on ANSYS, in which, the structure and fluid interaction is considered by Lagrangian fluid FEM approximation. An artificial earthquake and Qian’an earthquake are selected as load inputs for the model. The results show that, after considering the interaction between soil and structure, the dynamic characteristics of the tank changes, and produce the whole vibration shape of soil-tank. There are differences in the spectral components of the two seismic waves. The prominent frequency of the artificial earthquake is closer to the frequency of liquid-tank coupled vibration, and causes a larger horizontal displacement of the tank wall, which shows obvious elephant-foot deformation near the bottom of the tank. The stress response of the tank wall under the excitation of two seismic waves is small. The conclusion may provide some reference for the seismic design of the tank considering the effect of soil-structure interaction.

The dynamic through-soil interaction between underground station and nearby pile supported structure on viscous–elastic soil layer, under vertically incident S wave, is numerically studied. To this end, a commercial software for finite element analysis, ANSYS, has been further developed and enhanced for calculation in frequency domain, in which damping of hysteretic type can be considered for both the soil and the structures, so that structure–soil–structure interaction (SSSI) can be investigated making use of a direct methodology. The influence of arrangement of structures, shaking direction of seismic wave, distances between structures, shear wave velocity, damping of soil, burial depth and number of spans of underground structure on SSSI, in terms of horizontal acceleration magnification factor of ground structure, is addressed. For ground structure, different lengths of pile, stiffnesses, styles, and numbers of storeys and structures are considered. Maximum acceleration responses are also presented for 12 seismic inputs. Arrangement and shaking direction are two of the most important factors. The system response can be either amplified or attenuated according to the distance between adjacent buildings, which has been related to dynamic properties of the overall system. Those neighboring low-slung buildings around underground structure are heavily affected.

A novel, high-performance wide-bore electrophoresis (WE) system with inner-cooling has been developed. By introducing the mode of a shell and tube heat exchanger into this system to remove Joule heat generated during electrophoresis, it is feasible to extend electrophoresis from the conventional capillary (i.d.100 microm) to a wide-bore tube (i.d.1000 microm). The wide tube allows the loading of over 1.0 microL of the sample with an LOD of 3.0 x 10(-4) mg/mL (signal-to-noise ratio, 3:1). Satisfactory separations of model compounds have been achieved on the WE system.

A model mixture of six aromatic acids has been separated using a laboratory-made wide-bore electrophoretic device with aminopropyl-modified nanoparticles used as pseudostationary phase. Optimization of preparation of nanoparticles by an electrospray (ES) method is described. With the optimized electrophoretic method, 30 mmol/L acetate running buffer, pH 4.5, containing 1.0 mg/mL of nanoparticles as an additive was used, and 3.0 kV applied potential, improved resolution was achieved. The average theoretical plate number obtained was above 5.0 x 10(4) theoretical plates per meter with the highest value achieved in certain runs exceeding 1.0 x 10(5) theoretical plates per meter, which was better than previously reported results (approximately 6.7 x 10(4) theoretical plates per meter). Furthermore, repeatabilities of 2, 6.5, and 6% were obtained for the migration time, peak areas, and peak height, respectively. Additionally, sample capacity and sensitivity were improved by hundredfold using the novel wide-bore electrophoresis system compared to traditional CE.

In this paper, we aim at obtaining the deformation law and the mechanics characteristic of the supporting structure of 8 Shaped super deep foundation pit, including the deformation law and the plastic zone of the soil outside the structure. Based on the example of 8 Shaped super deep foundation pit for South Anchor of the Fourth Nanjing Yangtze River Bridge construction, the full three-dimensional finite element model was used to simulate the excavation of the whole foundation pit. Interaction between the supporting structure and the soil had also been taken into account in calculation. Compared with measured data, the results indicate that traditional design is conservative when applied in the design of 8-shape super deep foundation pit in account of space effect and arching effect, and the simulated model considering friction between the supporting structure and the soil reflects the soil pressure accurately.

In this paper, we aim at exploring method and process of semi-automatic evaluation of damage of buildings with computer and high resolution remote-sensing images. Change detection of remote-sensing images from IKONOS with a resolution of a meter prior to and after the earthquake was executed and the semi-automatically rapid evaluation of damage of buildings was studied both by case of north area of Dujiang Dam city in Wenchuan Earthquake. The change detection included difference method, ratio method, relevance method and false color composite. This paper proposed the process of semi-automatic evaluation. ENVI was secondarily developed for the suitability of semi-automatic evaluation. At last this concluded the collapse ratio of test area of 15.15%. In comparison with actual result and traditional measures, this method is much more convenient, rapid, credible, and feasible.

The interaction between 18-methyl norethindrone and ketoprofen including the displacement of ketoprofen from human serum albumin binding sites was investigated by capillary electrophoresis-frontal analysis method (CE-FA) at room temperature. A very large sample plug was introduced hydrostatically into the capillary (65 cm x 50 microm i.d., effective length of 35 cm) over 80 s at a height difference of 11 cm. The working conditions for CE-FA separation are as follows: operating voltage, 10 kV; running buffer, 67 mmol/L phosphate, pH 7.4. The unbound ketoprofen concentration was directly measured from the height of the frontal peak. When the concentration of 18-methyl norethindrone was increased from 0 to 200 micromol/L, the unbound ketoprofen concentration was found to increase from 22.4 to 26.4 micromol/L at 100 micromol/L total ketoprofen concentration and from 82.1 to 106.2 micromol/L at 200 micromol/L total ketoprofen concentration. From these data, it may be deduced that the administration of high concentration of 18-methyl norethindrone could displace ketoprofen from its secondary binding site.

A novel, high performance wide-bore electrophoresis (WBE) system with inner cooling has been developed. By introducing the mode of shell and tube heat exchanger into this system to remove Joule hea...