查看更多>>摘要：In order to study the effects of soil compaction, and soil physical and chemical characteristics after land reclamation, selected lands that were reclaimed after 1, 2, 3, 4, and 5 a, respectively, in the Majiata Mine of the Shendong Open Pit; tested the effects of soil compaction; and collected soil samples from 5 different depths, which are 0～7.62, 7.62～15.24, 15.24～22.86, 22.86～30.48, and 30.48～38.10 cm, respectively. The results sity of reclaimed soil is higher than that of undisturbed soil; this declines with the reclama-tent of reclaimed soil nutrients is lower than that of undisturbed soil. The lowest one is in the soil dumping site, which reaches the level of undisturbed soil after 5-year reclamation; in the soil dumping site; this declines with the reclamation.
查看更多>>摘要：To study the grouting reinforcement mechanism in jointed rock slope, first, the theoretical deduction was done to calculate the critical length of slipping if the slope angle is larger than that of joint inclination; Second, the numerical calculation model was founded by FLAC3D, so as to find the stress and deformation responses of rock mass in the state before and after grouting, the analysis results show that the range between the boundary of critical slipping block and the joint plane that passes the slope toe is the effec-tive grouting area (EGA). After excavation, large deformation occurs along the joint plane. After grouting, the displacements of rock particles become uniform and continuous, and large deformations along the joint plane are controlled; the dynamic displacement can re-flect the deformation response of slope during excavation in the state before and after grouting, as well as the shear location of potential slip plane. After grouting, the dynamic displacement of each monitoring point reaches the peak value with very few time steps, which indicate that the parameters of the joint plane, such as strength and stiffness, are improved; the stress field becomes uniform. Tensile area reduces gradually; whole stability of the slope and its ability to resist tensile and shear stress are improved greatly.
查看更多>>摘要：Briefly introduced the simple shear apparatus under high stress that was de-veloped from RMT. A series simple shear tests under high stress show that the relation curve between shear stress and tangential displacement under high normal stress is dif-ferent from the hyperbolic curve in direct shear tests, and the complete deformation proc-ess of interface under high stress can be described as nonlinear elastic-perfect plas-tic(NEPP). According to some characteristics of the fitting curve, the deficiency of the NEPP was pointed out. The mathematic "half value index" was used to illustrate that Weibull distribution with three parameters (WNEPP) can overcome the mathematical defi-ciencies of the NEPP. The advantage of the WNEPP is that the fitting curve of WNEPP more accurately coincided with the testing data was testified by further comparison.
查看更多>>摘要：The acid-base buffer characteristics of fulvic acid (FA) and barium fulvate (BaFA) were analyzed. Each share of the sample or model agents (phthalic acid and salicylic acid) were separately mixed into a series of shares of dilute solutions of HCI or NaOH with a se-ries of concentration. The original pH values of the solutions were arranged from 2 to 13. Final balanced pH of each share was measured. The pH changes show that FA and BaFA possess buffer ability, whereas the model agents do not. The tendency of balanced pH values was 5.4 for FA and 7.4 for BaFA, whereas the original pH was 4.0～8.5; balanced pH changed little. At room temperature, the maximum buffer capacities were as follows: 18.11 mmol hydroxyl per gram FA, 11.25 mmol hydroxyl per gram BaFA, 1.19 mmol proton per gram FA, and 1.45 mmol proton per gram BaFA. Mathematics analysis shows that logarithm of buffer capacities of FA and BaFA is linearly dependent on original pH. Com-pared with BaFA and model agents, it is concluded that FA buffer capacity against hydroxyl relies not only on its acidic groups, BaFA buffer capacity against hydroxyl does not rely on its acidic groups, and FA buffer capacity against proton is not related with its carboxyl and phenolic hydroxyl group. The pH values of FA-water solutions with different concentrations from 1 to 10 grams per liter were measured. Their pH values were slightly affected by its concentration. Thus, FA possesses a much stronger buffer ability against water dilution than common buffer agent. All the pH values of FA water solutions were very nearby 5.4, just the same as the balanced pH tendency for adding FA.
查看更多>>摘要：Using the lumping method, OH4, C3H8, C10H22, and C22H44 were chosen as the model products, and CO as the key component. The mathematical model of a gas-solid fluidized bed reactor was established based on some hypotheses. The consumption ki-netic model of CO was investigated, and the parameters were estimated by Universal Global Optimization with the Marquardt method. Residual error distribution and a statistical test show that the intrinsic kinetic models are reliable and acceptable. A model of carbon chain growth probability was established in terms of experiments. Coupled with the An-der-son- Schulz-Flory (ASF) distribution, the amount of specific product could be obtained. Large- scale cold model experiments were conducted to investigate the distribution of the gas (solid) phase and determine the function of the voidage with the location of the cata-lytic bed. The change tendencies of the components in the catalytic bed at different tem-peratures were computed and figured out. The calculated value computed by the model established for the Fe-based F-T synthesis catalyst fit the experimental value very well under the same operating conditions, and all the absolute values of the relative deviations are less than 5%.
查看更多>>摘要：Available silicone was melted from coal gangue samples from Hancheng dig-gings through calcination, digestion, and other means. The best calcination temperature was determined from a range of 550～1 150 ℃; and the best time, from a range of 0.5～5h by colorimetry method. The proper ratio of coal gangue, limestone, sodium carbonate, and caustic soda was then determined through orthogonal experiment. The results show that the proper extraction condition for available silicone is the ratio of coal gangue, limestone, sodium carbonate, and caustic soda at 1:0.5:0.1:0.05, calcination temperature at 700℃, and calcination time at 2 h. In this condition, the available silicone content can be more than 19.65%.
查看更多>>摘要：In order to improve the activity and eliminate some impurities, pretreatment was used before hydrothermal synthesis. The fly ash was mixed with an aqueous NaOH solu-tion, the alkali melted fly ash was also adopted, which is hydrothermally treated at about 104℃, and the liquid/solid ratio was controlled at 6:1. In order to control Si/Al molar ratio, SiO2 or Al2O3 powers were added to the fly ash. The results of XRD and SEM show that the alkali melted can activate fly ash and eliminate its quartz and mullite, along with the improvement of Si/Al molar ratio and alkalinity. In addition, zeolite Na-A changes into so-dalite gradually, and nepheline is the synthesized intermediate product. Those results were discussed on the basis of a formation mechanism of zeolite from fly ash.
查看更多>>摘要：Because of the complication of turbulence's mechanism and law as well as the jet pressure in nozzle is difficult to test by experiment, five turbulent models were applied to numerically simulate the turbulent flow field in convergent-divergent nozzle. Theory analysis and experiment results of mass flow rates conclude that the RNG κ-ε model is the most suitable model. The pressure distribution in the convergent-divergent nozzle was re-vealed by computational fluid dynamic (CFD) simulating on the turbulent flow field under different pressure conditions. The growing conditions of cavitation bubbles were shown; meanwhile, the phenomena in the experiment could be explained. The differential pres-sure between the upstream and downstream in nozzle throat section can improve the cavitating effect of cavitation water jet.
查看更多>>摘要：The band conveyer driven by linear friction is a new device. It can reduce drive size and conveyor belt tensity, and increase delivery capacity. It has feasibility and usabil-ity particularly in altering the original conveyer and solving the problems of capacity insuffi-ciency. The technology has brought certain difficulty for engineers, because it has certain difficulty both in theory and in calculation. Therefore, Visual Basic 6.0 programming tech-nology was used to develop a set of "the design system of the band conveyer driven by linear friction." After being proved in the field, it can completely meet the demands of the design. This paper introduced its main theory or basis in design, so as to provide related technical support to this kind of project.
查看更多>>摘要：Based on the applications of virtual reality technology in many fields, introduced the virtual reality technical basic concept, structure type, related technique development, etc., tallied up applications of virtual reality technique in the present mining industry, in-quired into core techniques related software and hardware, especially the optimization in the setup of various 3D models technique, and carried out a virtual scene to travel exten-sively in real-time by stereoscopic manifestation technique and so on. Then it brought forward the solution of virtual reality technique with software and hardware to the mining industry that can satisfy the demand of different aspects and levers. Finally, it show a fine prospect of virtual reality technique applied in the mining industry.
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