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The uniaxial creep tests were carried out for deep limestone from Chongqing adoptal by the MTS815 servo controlled rock mechanical test system. Meanwhile, the DISP 2 based AE system was used to test acoustic emission (AE) signal. It is found that AE can better reflect rock microstructure such as diffusion of lattice defects, opening and close of the pore and fracture, compatible deformation among particles, the generation and connection of micro ruptures. Through different creep model parameter inversion, 〖JP2〗it is concluded that either the logarithmic function creep model or the exponential function can better reflect deep rock creep deformation behavior and the logarithmic function creep model is much better. 〖JP〗 相似文献
94.
This paper analyzes the steel reinforced concrete large span transfer truss joints using the finite element analysis software ANSYS, and get the joints deformation and the mechanics increase, such as deformation properties, stress distribution. The monitoring results during construction phase show that nonlinear numerical simulation analysis, which is in good agreement with the test results, is an effective method for the mechanical property analysis on this kind of structural components. 相似文献
95.
Adsorption and corrosion inhibition behavior of mild steel by one derivative of triazole-phenylamide in acid solution 总被引:1,自引:0,他引:1
A new triazole-phenylamide derivative (DOT) is synthesized and its inhibiting action on the corrosion of mild steel in 1 mol/L HCl solution is investigated by means of potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. Thermodynamic and kinetic parameters are calculated and discussed. Then the surface morphology is studied by scanning electron microscopy (SEM). Results show that DOT strongly inhibits the corrosion of Q235. The inhibition efficiency of 0.001 mol·L-1 DOT is more than 96%. Polarization curves indicate that the DOT acts as a mixed-type inhibitor, the cathodic and anodic processes of corrosion are suppressed. Thermodynamic and kinetic parameters are obtained from weight loss of the different experimental temperatures, which suggests that at different temperatures (298~333 K) the adsorption of DOT on metal surface obey Langmuir adsorption isotherm model. The adsorption processes are exothermic reaction and belong to chemisorption and physisorption. 相似文献
96.
结合伊春市福轩木业公司细木工板生产线改扩建项目实际,对细木工板项目的投资及经济效益进行了详细分析,论证了该项目的经济可行性。 相似文献
97.
Organic biocides as timber preservatives have aroused more and more attention,because metal salts especially arsenic,chrome and so on, have been suspected to be poisonous to the soil and aquatic animals,as well as the disposal of preserved timber wastes.Therefore,a number of effective organic biocides have been selected to prevent wood or bamboo from decay,mildew, stain and so on.Most of these products have entered into the market.With people’s increasing awareness of the environmental protection,organic biocides will eventually play important roles in timber preservation in the future.This paper summarized the studies on application of organic biocides as wood or bamboo preservatives,including resistant mechanisms,commonly applied types and effects against wood or bamboo fungi,approaches to detecting the amount of organic biocides in timber and their influences on the environment.Based on the discussion above,the authors predicted the developing prospect of organic biocides in timber preservation. 相似文献
98.
山莓叶中茶多酚的提取工艺研究 总被引:10,自引:0,他引:10
用正交实验方法研究了从山莓叶中提取茶多酚的提取工艺,得到了提取茶多酚的最佳工艺条件。该工艺条件具有操作简单、产量高、无毒无污染、成本低等特点。 相似文献
99.
基于河北省木兰围场国有林场管理局域内2hm2典型天然次生林植被群落调查,探讨次生林下灌木群落结构特征,研究显示:1)研究区29种灌木分属于15科22属,包含灌丛12 878丛、灌木20 861株,以毛榛(Cory-lus mandshurica)、五角枫(Acer mono)幼苗、锦带花(Weigela florida)为该群落优势种;2)80%以上的灌木基径过1cm,尤以青杄(Picea wilsonii)和华北落叶松(Larixprincipis-rupprechtii)幼苗的平均基径最大;3)以2m高度为界限可将灌木划为两层,上层灌木基径和冠幅明显优于下层灌木;4)从空间分布角度而言,不同灌木种群在频度、相对显著度和相对多度等方面表现出一定的空间异质性。 相似文献
100.