Mine tailings dam is an important production facilities, a large number of dams memory tailing sand and water, once the dam break, the tailing dam and water on the debris flow will be in the form of emission, the consequences would be disastrous. Their predecessors do a lot of theoretical research and engineering example statistics show that the impact of the tailings dam safety and stability of various factors, the location of the dam seepage infiltration is extremely important factor. The need for more stability in the evaluation of the tailings dam dam seepage field study to determine the location of infiltration and analysis of its impact, and propose alternatives.This article study on the rule of tailings dam changes of the seepage. Xi Ye Shan-tailing dam in several decades of operation has shown a lot of failures, and considering raising its 100 m to the situation, it is need to study the stability of its seepage. Following are the mainly completion of work:(1) Through on-site inspection, testing analysis, master-Ye Shan tailings dam dam operation in the history and present situation and geotechnical engineering;(2) For the tailings dam material characteristics, the introduction of seepage theory, the seepage field two-dimensional finite element model, simulate, the dam of the changes of seepage;(3) Calculation of the rule-of-tailings dam specific types of damage and stability of the dam evaluation analysis and treatment measures;(4) Xi Ye Shan-tailing raise the tailings dam 100 m to conduct a feasibility analysis, methods of expansion dam design and analysis of the dam heightening the flow stability;(5) For this study the contents and methods, put the text of inadequate light industry and the development of future work in areas for improvement.
Post about "Stability"
Research on Extraction, Physicochemical Property and Antioxidation of Purple Dioscorea Batatas Decne
Dioscorea batatas Decne, an annual or perennial twining liana plant, belongs to dioscorea batatas family. It is mainly distributed in tropical and subtropical areas in Africa, South America, and Southeast Asia. Dioscorea batatas Decne is rich in carbohydrates, and also contains protein, various vitamins, chemicals, indicant, and mucilage which are beneficial to human body. It is bright red, and has developed rhizomes in the shape of a sole, thus named. Its colors vary from white to puce （purple）. Purple ones indicate that they contain certain pigments, belonging to anthocyanin. Anthocyanin, a kind of flavonoid compound, is an edible natural pigment of water-solubility. At present, few researches have been done on the pigment of Dioscorea batatas Decne. Domestic researches have been limited to the separation and extraction of it. In the paper, the writer has made an initial exploration into the separation and extraction of the pigments in purple Dioscorea batatas Decne, and the stability and the biological activity of extracorporeal anti-oxidation have also been studied in the paper, which has provided a theoretical foundation on which to take advantage of anthocyanin, and develop functionality foods from Dioscorea batatas Decne.Based on Orthogonal experiments, the paper first studies the best technological conditions under which to lixiviate pigments of Dioscorea batatas Decne. The results show that pure anthocyanin can be extracted by filtering steep, adsorbing colophony, decompression and cubage reduction, under the condition that 1.5 percent of citric acid ethanol liquor serves as the best lixiviator, which should be heat up under the constant temperature of 60℃for 60 minutes, and the proportion of general materials should be 1:10.At the same time, the paper also studies the stability of the pigment in purple Dioscorea batatas Decne, showing its stability under the condition of pH<3 high acid liquids, and its unstability under the condition of pH > 5 liquids. It possesses certain heat-resistance, but the temperature should not be over 90℃. It has relatively poor lightfastness. Most metal ions will not have great effects on the stability of the pigment, while Al3+、Fe3+ do have great impacts, among which Al3+、Fe3+ tend to increase the absorbency of the pigment.In the paper, two extracorporeal anti-oxidation models have been adopted to study the extracorporeal anti-oxidation of pigment in purple Dioscorea batatas Decne so that the potential of pigment as a function gene of anti-oxidation can be fully understood. The results indicate that pigment in purple Dioscorea batatas Decne possesses considerably strong ability to eliminate·OH and·O2-, and its ability has so much to do with its thickness.
In this thesis, Ti/SnO2+Sb2O5/IrO2+Ta2O5 composite electrode was prepared by thermal decomposition technology to improve the lifetime and reduce cost of Ti-based metal oxide anode. Firstly, effect of various calcination temperatures on the structure, surface morphology, stability and electrocatalytic properties of the intermediate layer and the surface active coating of Ti/SnO2+Sb2O5/IrO2+Ta2O5 electrode was investigated, and the optimal calcinations temperatures was determined mainly by the elctrocatalytic properties and accelerated life of the electrode. Secondly, the role of intermediate layer containing Sn-Sb element on Ti/SnO2+Sb2O5/IrO2+Ta2O5 electrode was discussed, and strcture model of the corresponding electrode was proposed. At last, the failure behavior of Ti/SnO2+Sb2O5ArO2+Ta2O5 electrode was investigated.Polarization curve measurements, cyclic voltametry （CV）, electrochemical impedance spectroscopy （EIS） investigation and accelerated life test were used to obtain information about the electrochemical properties of the electrode.The surface morphology and composition of the intermediate layer and the surface coating were characterized by scanning electron microscopy and energy disperse spectroscopy （EDS）.The crystal structure of the coated anode was examined by X-ray diffraction.Results indicated that calcination temperatures had remarkable influence on the properties of Ti/SnO2+Sb2O5/IrO2+Ta2O5 electrode. When the intermediate layer prepared at 500℃and the surface active coating parepared at 450℃, Ti/SnO2+Sb2O5/IrO2+Ta2O5 shows good electrocatalytic performance and long accelerated life.The present of an intermediate layer cotaining Sn-Sb element can effectively prevent from TiO2 insulation layer formed during the electrolysis, depress the interfacial resistance of the electrode and improve the adhesive power between both the active coating and Ti substrate, which lead that accelerated life of Ti/SnO2+Sb2O5/IrO2+Ta2O5 electrode is as two times as that of Ti/IrO2+Ta2O5 electrode. Furthermore, Ti/SnO2+Sb2O5/IrO2+Ta2O5 electrode has much better electrocatalytic performance than Ti/IrO2+Ta2O5 electrode.The whole electrolysis process an be divided into three stages including “breaking in”, stable and degradation regions by the analysis of the failure behavior.The results showed that the degradation was due to the dissolution of the active component and the deterioration of the interface between Ti base and oxide catalys.Moreover, the surface activity numbers were greatly reduced and the resistance was increased significiantly after passivation of the electrode.
The tribological characteristics of Ti3SiC2-class ceramic and its composite material have been researched in this thesis. The stability of friction and its effect to current-carrying friction and wear have also been investigated. We have investigated the friction and wear characteristics of Ti3AlC2 ceramic bulk preliminary in the case of low speed and lubricated. The following are some results of research.1) The friction coefficient and wear rate of Ti3SiC2 and Ti3AlC2 ceramic increase in the case of current-carrying compared with non-current carrying , and the stronger the current intensity is , the more notable the amplitude is. On one hand, the friction coefficient and the wear rate decrease as the normal pressure increases. On the other hand, the friction coefficient increases as sliding speed increases, and the wear rate has the opposite intend. The increase of the friction coefficient is related to the hard crystal phase’s generating （such as TiC ） on the surface of the wear, while the increase of the wear rate is attributed dominantly to the ablation of micro-arc, interaction of mechanical friction and couplings of thermal-dynamical.2) The composite material of 50Cu/Ti3AlC2 shows excellent current-carrying tribological characteristics against silver-copper alloy in the case of current-carrying. This is mainly related to Cu（Al） alloy layer which has network structure and serves as conducting channel in the composite material. The friction coefficient of 50Cu/Ti3AlC2 has little fluctuation as current intensity and sliding speed change, but the wear rate increase obviously as current intensity and sliding speed increase. This is related primarily to strong ablation of micro-arc caused by large current intensity and sliding speed.3) The friction coefficient of Ti3SiC2-class material displays fluctuate character randomly in the whole experimental process and the fluctuating behavior of relative stabilization period obeys normal distribute. The friction of material is more stable as the normal pressure increases and be more unstable as the sliding speed increases. The strong stability can restrain the producing of micro-arc effectively in the process of current-carrying friction and reduce the wear rate of material in general. The weak stability results in more effect of the ablation of micro-arc on the wear surface which produces in the friction, and in the meantime, it also increases the wear rate of material in general. 4) The friction coefficient of Ti3AlC2 ceramic bulk in the case of low speed and oil lubricated has one less magnitude than it in the dry sliding state and the wear rate has almost four less magnitudes. It results from the formation of lubricant film under lubricated state which changes the friction and wear state between friction couple, and the direct contact between minor particles in the process of friction has become the contact between lubricating oil molecules, therefore, it’s difficulty to break the minor particles and the abrasive wear which emerging under low speed and dry sliding conditions has disappeared, so the friction coefficient and the wear rate reduce greatly.
In this paper, research is focused on the two aspects. Firstly, the comparing study on the stability of emulsion liquid membrane(ELM) with different operation parameters and conditions. Secondly, the study on separation of toluene and dichloromethane in model industry flue gas by emulsion liquid membrane in packet tower. Thirdly, the study on the electrostatic broken emulsion in ELM separation.The first part is the premise of the second in which some operating parameters may affect the stability and the separation efficiency of ELM were investigated, including the concentration of surfactant, the ratio of emulsion and water, the rev of stirrer and so on. Experiments data showed that there were some kind of “critical value” for those factors respectively. Under this critical condition, both the stability and the seperation efficiency of ELM were satisfying. When the rev of stirrer was 3000rpm, the ratio of oil and water was 1:2, the concentration of span80 was 2%, the ratio of emulsion and water was 1:6, the rev of second stirring was 400rpm.To toluene,when the concentration of it is 8000mg/m~3 ,the ratio of ELM and air is2.9,the efficiency can be the highest.To dichloromethane,compared to the concentration of the gas,the ratio of ELM and air is more important,when the ratio is 2.1,the efficiency of dichloromethane absorbtion is the highest.The study of the electrostatic broken emulsion of ELM includes two aspects, demulsion voltage and temperature. The results showed that demulsion voltage and demulsion temperature all have impact on the demulsion efficiency of ELM.Overall,the higher the demulsion voltage and temperature are, the demulsion efficiency is better. oil-water separation results can be obtained when the voltage is set above demulsion critical voltage.
Color filter is one of the key components of the Liquid crystal display, it needs performances of high-transmittivity, thermal stability and lightfastness and so on. The form of organic pigment which is used for colorant affects the performance of luster, pigmentation, envelop, transparency and tone. Therefore, organic pigment must to be fine and symmetrical in the photoresist.Ultrafine organic pigment has a high surface energy, it is easy to form bulky particle by mutual attraction of particles that leading the system instability, and the pigment is not suitable for photoresist in color filters. The purpose of this research is to disperse and stabilize the red organic pigment P.R.177 so that it can be used for modulation the photoresist.Pigment, dispersant, dispersed resin and dispersing agent are needed in the pigment dispersed system. Impacting of dispersants and resins on the particle size and stability of P.R.177 pigment dispersed system was discussed, the type of dispersants and resins should be compatible with the other components of photoresist. The particle size showed that the components of the system have great effect on the dispersion and stability of pigment. In the same condition, the amount of dispersant and resin has a best value, too small or too much will cause fiocculation of the system, resulting in instable system.Secondly, different pigment dispersed systems need different decentralization and rubbing processes. The impacting of dispersion process on P.R.177 pigment dispersed system also discussed and the results show that the particle size can not reduce along with the increasing of rotate speed, but there is a best range of the rotate speed, too fast will made the particle size augment. And it is can not judge the effect of rubbing to the pigment system with time, only if pigment particles own adequate energy can be minimized smaller, so in order to get a stable pigment dispersed system, the appropriate energy input is necessary. So in the same condition, more energy is required for more pigment solution.Finally we got the small particle size, narrow particle size distribution and high stability pigment dispersed system after a large number of theory analysises and experiments. The photoresist have better stability and chroma which brewage by this pigment dispersed system. The photoresist was spin coated on glass substrate, the red pels on the color filter which owns good performance of chroma and optics through the semiconductor prosess such as exposal and develop.
Desertification is one of biggest environment questions in the world, which also is the main manifestation of desertification in the north of our country. In recent years, the sandstorm occurred frequently, which has do a great harm to ecological envioment. Yanghe sandy land is one of the important dustsources of Beijing and Tianjing sandstorm source, located at Zhangjiakou area, Hebei province.To combat the wind sand disaster, in recent year this area has made ecological construct cosmically and gained favorable effects. This paper take Huangyangtan sandy land as example, based on a mass of research and observation, Using grey relational analysis method, from the physical properties of soil, soil chemical properties, the growth of forest, forest plant diversity, comprehensive quantitative evaluation of different types of plantation stability, and for the region to improve the status of Plantation stability of the measures and silvicultural measures. The result indicated:(1) Through determinaty and analysis the Huangyangtan physical properties of soil, we can see: the different types of plantations, The comparison of soil aggregate composition is very greatly. In the composition of the soil particles, 1～0.1 mm particles formed in the percentage of between 34.63 to 96.01 percent, the soil is composed of machinery as a percentage of the maximum. Soil particles larger than 0.05 mm of the particle composition of the total of 87.98 percent, this component can be seen from the Huangyangtan region of sandy soil in plantations still quite serious. We selected in the water holding capacity of soil and retention indicators, soil bulk density in 1.43～1.68 g/cm~3 between the soil in the field capacity between 14.94 to 24.88 percent, water retention and retention is relatively weak, and the soil containing Water only between 3.74 to 6.68 percent, relatively low moisture levels, and between all levels of soil moisture changes were not evident.(2) Huangyangtan region due to relatively large annual sandstorms, litter the ground floor of relatively small, resulting in the area of soil organic matter content of low organic matter content of the highest kind for the 5th kind of poplar and apricot mixed for 7.812 g / kg, the smallest on the 14th for the kind of Amorpha fruticosa X the Scotch Pine mixed shrub land of organic matter content of 1.488 g / kg. Through comprehensive evaluation on the 5th kind of poplar and apricot mixed forest is the highest correlation coefficient of soil nutrients, soil nutrient status of the best.(3) Through the Huangyangtan different plantation growth, the average growth of trees of Populus popular s and Populus alba L.var.pyramidalis are the largest, and still in the growth stage of the age class of small oriental arborvitae, black locust, elm’s crown The average annual growth rate of crown is the largest. On the 10th of the kind of Scots pine, the average growth of plants, stand-year average and the average annual growth of net productivity are the highest. Scots Pine Forest through a comprehensive evaluation of the best growth conditions, but the stand density is relatively small.(4) Through the different types of plantation forest diversity of plant species, forest plantations that Huangyangtan a single level, herbs only during the rainy season when the re-germination, and less variety in the investigation of the 16 samples And a total of 31 kinds of plants, under Section 15. Mainly concentrated in the legume, Compositae, the three branches of the grass family. In a kind arguably the largest number of plant species for the first three Feipeng, Lespedeza, green bristlegrass. Huangyangtan region and a total of 92 branches, 288 genera and 527 kinds. This see: Huangyangtan Plantation under the plant diversity is also low, due in large plantations in the introduction of native species, to raise plantations of species diversity.(5) Evaluated the plantations with ash association coethcient analysis, the result that the plot 5, Poplar×A pricot mixed forest and plot 10 Amorpha fruticosa forest, are the most stability forest stands. The relatively stability plantations are the polt 1 poplar×Robinia pseudoacacia mixed forest, plot 12 Platycladus orientalis of 17 years, plot 7 Poplar, plot 11 Caragana korshinskii Kom, plot 6 elm trees of 13 yeas,plot 3 elm trees of 7 years, plot 4 Poplar of 9 year, plot 15 Populus popular s, plot 16 Populus alba L.var.pyramidalis,The relatively middle stability plantations are plot 2 Robinia pseudoacacia of 5 years, plot 9 Elaeagnus angustifolia L, plot 13 Platycladus orientalis of 7 years, plot 14 Amorpha fruticosa×the Scotch Pine, The instability plantations is plot 8 Salix psammophila.(6) Aim at the plantations in Huangyangtan, take measures by water and site management, optimize community structure, man-promoted natural regeneration, humanity factor, enhancing the stability of plantations.
As a kind of burgeoning sports food, energy gel made from starch has an enormous development potentiality and a promising market. However, the research on energy gel is very limited in our country at present. The products on the oversea market have different technological conditions and high price. To fulfill the special requirement of the sports food-easy taking, easy swallow, and easy digestion and so on, maltodextrins made from potato starch were prepared and their properties and structures were analyzed according to the characters of energy gel. In conclusion, the optimal materials and technological condition were determined, so an energy gel with high performance was prepared. Furthermore, the physiology properties of energy gel were evaluated by animal experiments and the releasing rate of energy was calculated.Firstly, corn starch, potato starch and waxy corn starch were used as raw materials and series of maltodextrins with different dextrose equivalent (DE) were prepared, then their digestibilities were analyzed according to energy gel’s characteristics. The stability of several kinds of maltodextrins with the different DE value was studied, through determining sedimentation volume, suspension capability, viscosity and transparency. The maltodextrins made from potato starch(DE>10) was finally chosen to produce energy gel.Secondly, potato starch slurry (25%) was treated withα-amylase at 95℃and pH6.0 for 25min, then kinds of maltodextrins with different DE value were produced with the various concentration of enzyme. The properties and structure of maltodextrins with different DE value were analysed by Rapid Viscosity Analyzer (RVA), Scan-electron Microscope (SEM), High Performance Liquid Chromatography (HPLC), Gel Permeation Chromatograpy (GPC) and Differential Scanning Calorimetry (DSC). The results showed that the viscosity of the maltodextrins decreased as the DE value increased, but increased as the concentration increased. Partical surface structure, maltose content, molecular size and the molecular weight distribution were main influencing factors of sample properties. The sample was stable when the molecular weight was low and distributed evenly, and the micromolecule content was high. In addition, by Fiske One-Ten Osmometer analysis, the main raw material of energy gel was found to be maltodextrin made from potato starch with a DE value of 15.82 and the solid substance content was 55% through rheometer and sensory evaluation.The optimal prescription of energy gel made from starch was confirmed: total weight of the products 45g, starch hydrolysate 25g, sodium 40.5mg, potassium 13.5mg, magnesium 4.5g. To improve the product’s stability, fluidity and taste, the stability of viscosity was studied by homogenizer under different pressure, and the results showed that the product could keep stable for nearly 5 months after 40 MPa homogenization. An in-vitro procedure to determine the digestibility of carbohydrate was set up, using the releasing rate and content of the reducing sugar to investigate the digestion rate of the energy gel. The experimental results indicated that energy gel could offer enough energy in 40min. Comparing with native starch and soluble starch, this product had the best digestion rate. Besides, the existence of sodium, potassium and magnesium had no influence on the energy releasing rate and rheological property of energy gel made from starch.At last, the physiology properties of energy gel were investigated by animal tests and the energy releasing rate was also estimated. The results showed that the energy gel was safe and didn’t cause death in mice, and it had a benefit to maintain the level of blood sugar of the trained mice and significantly prolong the swimming time of the mice. Hence, the energy gel made from starch had an obvious effect on the mice’s exercise performance and it could be developed as sports food.
β-glucanase is an important industrial enzyme,it could degrade theβ-glucan in corn such as barly, so it’s especially important in brewing and feed stuff industries.The breeding ofβ-glucanase high-producing strain, the fermentation condition and medium of flask fermentation and character ofβ-glucanase were investigated in this thesis. The main results were as follows:By UV radiation mutation method to the parental strain Aspergillus usamii M12, M12-9-5, aβ-glucanase producer was derived with enzyme activity of 57.85U/mL in the flask fermentation, which was increased by 88% compared with the parent stratin after the single colony separation, plate screen and flask fermentation experiment. The new mutant strain was stable for theβ-glucanase activity production. The condition of flask fermention was determined through single factor experiments: temperature 30℃, initial pH 5.5, medium volume 30mL of per 250mL shaking flask, the rotate speed of swing bed 200r/min, cultivating time of seed 18h, seed volume 13%, cultivating time 72h.The medium of shaking flask fermentation was optimized through Placket-Burman and RAS experiments. The optimal medium compositions（g/L） were determined as: barley flour 25.9, wheat bran 14.1, （NH4）2SO4 20.0, NaH2PO4 1.15, CaCO3 5.0, tween 80 1.5, FeSO4·7H2O 0.2, CaCl2 1.56, NaCl 1.44 and malt sugar 5.0. And theβ-glucanase activity was 307.20U/mL. On the base of shaking flasks fermentation, the enzyme production in a 5L automated jar fermentor was studied, the highestβ-glucanase activity was 323.91U/mL with 60h fermentation.It was investigated preliminarily for theβ-glucanase character by the fermentation liquid. Its optimum pH was 4.5, it could be stable during pH 37; Its optimal temperature was 55℃, it could be stable under 50℃. Some ions （1mmol/L） such as Co2+, Ca2+, Fe2+ and Na+ done good forβ-glucanase activity, while the Sn2+, Pb2+ and Zn2+ were harmful for its activity. Pepsin and trypsin have no significant effect onβ-glucanase activity.The protective agents such as xanthan gum, glycerol, albumin, NaCl and CaCl2·2H2O could improve the stablility ofβ-glucanase. The orthogonal experiment was used to optimize the best combination of different protective agent. The result was:CaCl2·2H2O 2.0mmol/L, xanthan gum 4g/L and glycerol 130g/L. The complex protective agents could enhance the enzyme thermostability, and could enhance the storage stability ofβ-glucanase with 1g/L potassium sorbate, the relativelyβ-glucanase activity was 88.47% after storing at room temperature for 3 months. It was increased by 15% comparing with the control.
Electronic warp let-off device is the key part of air-jet loom, and its main function is to let the warp with suitable tension and make the tension constant. Electronic warp let-off decide the quality of the fabric, which will be the main study direction in future.The component of the electronic warp let-off and the study status and trend were introduced in this paper first. And then, three traditional evaluation methods of electronic warp let-off device were introduced.Dynamic tension could embody the real performances of electronic warp let-off device, so, exact dynamic tension acquisition is the key of this subject. Digital test system was used to obtain the dynamic tension. The test system is composed of tension sensor, standard bridge, dynamic resistance strain gauge, A/D digital data acquisition card, PC record equipment. The tension F on the sensor has linear relationship with the output voltage AU which is F=10△U. On base of these, warp tension was embodied by the voltage. The dynamic warp tension was analyzed with tension wave, probability density function of warp tension in this paper. It is easy to found out the beating tension and heald level tension from the tension wave. Probability density function shows that the most reasonable distribution of warp tension is normal distribution.Then, three indexes, warp tension stability and consistency, dynamic warp tension constancy from big beam to small beam, dynamic warp tension reversibility when starting, were proposed to analyze the electronic warp let-off device of three kinds of air-jet loom. Stability of electronic warp let-off device of two kinds air-jet looms was analyzed respectively while weaving different specification fabric with the tension fluctuation stability and consistency. The tension stability and consistency was embodied by tension range rate and similarity respectively. The results show that the tension range rate was below 10% while Picanol air-jet weaving two different specification fabric. And the least similarity was 0.97 and 0.96 respectively. Furthermore, tension range rate of air-jet loom was below 10%. And the least similarity was 0.97 and 0.95. The warp tension fluctuation stability and consistency of Picanol and JAT air-jet loom is better. Therefore, the performances of electronic warp let-off devices of two kinds of air-jet loom are stable. According to compare the tension fluctuation stability and consistency of three kinds of air-jet loom, the results were proposed that the performance of Picanol air-jet loom is the best and Surprise air-jet loom is the worst.About the control ability of warp let-off device to keep warp tension constant, three special warp tensions were analyzed to embody the control ability. The smaller the tension change rate is, the better the warp tension constancy is. Picanol air-jet loom and JAT air-jet was selected to compare their adjustment ability to warp tension constancy. The results show that the tension change rate of two air-jet looms was is about 20%. However, the tensionchange rate of Picanol is bigger than JAT air-jet loom, which shows that adjustment ability electronic warp let-off device of JAT air-jet loom is better than Picanol air-jet loom.At last, the adjustment and control performance of warp let-off device of three kinds of air-jet loom was compared with the warp tension reversibility while the loom starting. The adjustment and control performance of warp let-off device was measured with the tension recovery time. According to the analysis of tension reversibility, three conclusions were obtained. The recovery time of Picanol OMNI-190, JAT710 air-jet loom and Surprise air-jet loom is 2.64 seconds, 3.29 seconds and 3.74 seconds respectively. And their recovery time is some short. These results show that the adjustment and control performance of warp let-off device of Picanol air-jet loom is better than other two kinds of air-jet loom. And the adjustment and control performance of warp let-off device of Surprise air-jet loom is the worst.