T2 cutoff value is one of the most important parameter in T2 spectrum. NMR measurement results of samples such as movable fluid saturation、irreducible water saturation will be scientific and accuracy when T2 cutoff value select scientifically and accurately.Centrifugal method was general method used at home and abroad to calibrate T2 cutoff value, and most experts and scholars at home and abroad selected 100 psi as best centrifugal force calibrating T2 cutoff value glutenite and carbonatite cores. Most foreign scholars believed that T2 cutoff value of sandstone cores was about 33 ms and domestic scholars generally believed that T2 cutoff value of domestic sedimentary reservoirs cores was less than 33 ms. In majority study abroad most T2 cutoff value of carbonatite cores distributed between 90 ms and 100ms, and never saw author relevant reports yet about T2 cutoff value of vulcanite reservoir cores.Large number of core analysis results showed that 100 psi as the best centrifugal force of calibrating T2 cutoff value might be not suitable for glutenite cores have low porosity and low permeability and special lithological cores such as carbonatite cores and vulcanite cores.This paper selected a certain number of representative cores of glutenite have low porosity and low permeability、carbonatite and vulcanite, and carried on best centrifugal force calibration experiments. each of cores were carried on NMR measurement after each of six or seven different centrifugal force, author can got that 200 psi was suitable to be best centrifugal force calibrating T2 cutoff value for glutenite cores, and 400 psi was suitable for carbonatite and vulcanite cores in this paper, and corresponding lower limit of valid throat is 0.1μm for glutenite and 0.05μm for carbonatite and vulcanite.Under best centrifugal force, author selected a lot of representative Glutenite、carbonatite and vulcanite cores and carried on centrifugal experiments and NMR T2 measurement, and determined T2 cutoff value of each cores, This paper also selected a certain amount of representative fresh oil-bearing sandstone for calibrating T2 cutoff value, and analyzed influence of T2 cutoff value with original wettability of core. In this paper, T2 cutoff value of glutenite cores mostly distributed between 10 and 30 ms, carbonatite cores were about 100ms. T2 cutoff values of vulcanite cores changed great with lithology, and average T2 cutoff value of rhyolite cores was 87.91 ms, tuff was 52.02 ms, and volcanic breccia was 36.28 ms.On the basis of ensuring T2 cutoff value, author analyzed relationship between NMR irreducible water saturation in different cores and porosity、permeability, and established analytic method of irreducible water saturation、movable fluid saturation of vulcanite core. NMR results of some Daqing oilfield vulcanite cores and gas test results of corresponding reservoir and CT results were compared in this paper.
Post about "wettability"
Utilizing crop straws producing the non-wood based panel is one of the popular projects in field of composite study around the world. Wheat is one of the most popular food plants that been cultivated in China. While providing food supply is also bring a large number of waste wheat straw yearly. Some old process on waste wheat straw such as burning can rise severe environmental problems. Thus, the exploitation of wheat straw has been becoming more and more concerned in China. In this experiment, I use lipase,xylanase,mixed enzyme,steam treatment and low temperature plasma treat wheat straw.Thus study the low of the surface wettability, chemical groups and bonding strength of wheat straw.The change law of surface contact angle and free energy of wheat straw show that surface wettability is improved after wheat straw was treated by enzyme. The contact angle of wheat straw is decreased. The surface free energy of wheat straw is increased. Steam treatment and low temperature plasma treatment also improved the surface wettability of wheat straw. The best condition of lipase for this treatment were reached at a pH value was 7.0,a temperature of 50℃,a time period of 7h; The best condition of xylanase for this treatment were reached at pH value was 5.0,a temperature of 50℃,a time period of 5h.I can see the surface of wheat straw was treated is rough by scanning electron microscope. By means of FT-IR, free radical and active functional group on wheat straw surface that treated by enzyme had increased in a great extent. These methods can improve the surface bonding strength of wheat straw.
In order to study the influence of two different enzymes treatment on the five kinds of wood surface properties, this paper takes Maple、Sapelli、Prunus serotina Ehrh、Mongolian Scotch Pine、Pinus ponderosa as the main raw materials, firstly they are treated by lipase and xylanase respectively, and study the variation of their surface wettability through measuring surface contact angle. Secondly, on the basis of optimum process, which are concluded by the single lipase or xylanase treatment on five kinds of wood, then use mixed-enzymes react on these different wood by two processes, measuring and calculating their surface free energy , and shearing strength, analyzing the relation between wood wettability and shearing strength. Thirdly, compare the change of different wood surface physical structure, primary functional group and variation of wood surface properties by XRD, FTIR,SEM and other modern analytical methods, on the lipase-treated , xylanase-treated and untreated wood, the research results show that: the results by X-ray diffraction prove that the crystal degree of wood cellulose treated by lipase and xylanase respectively is less than untreated; the results by FTIR prove that lipase or xylanase treatment on wood surface primary funtional group such as–OH, -CH are more than untreated; the results by SEM prove that lipase or xylanase treatment on wood surface are very scraggly, part of tore velamen is destroyed. All change of wood surface structure makes for improving wood surface wettability and shearing strength.This study provides more datas for the control mechanism which studys enzyme treatment on wood surface properties, and also supply bases for enriching correlative basic theory.
Study about the Characteristic of Bamboo Surface and Interface by the Treatment of Low Temperature Plasma
In order to extract and utilize the properties of bamboo surface and interface sufficiently, from several points of view, such as wettability、chemistry composition、free radicals diversification、surface appearance、bonding strength of interface and so on, this paper analyses and studies the characteristic of bamboo surface and interface before and after the treatment of low temperature plasma. The conclusions of the paper have some direction meanings when dicussing the principle of the treatment of low temperature plasma to the surface and interface of bamboo. Expect to expand the appliance scope of plama and the force of bamboo material utilization when treated by plasma.Started with the changes of wettability of the surface of bamboo when treated by the low temperature plasma, the study found relatively great changes happened between Lifshitz-vander waals (LW) energy and alkali parameter. Thereinto the changes of Lifshitz-vander waals (LW) energy show that low temperature plasma bring some physics changes, the changes of alkali parameter show that low temperature plasma bring some chemistry changes.The research of chemistry composition and relatively free radicals concentration of the surface of bamboo show that the degree of oxygenation of bamboo green skin is better than that of bamboo yellow endothecium and the amplitude of free radicals concentration of bamboo green skin is outclass than that of bamboo yellow endothecium, when treated by the low temperature to the surface of bamboo. These conclusions validate the changes of alkali parameter with the treatment of the low temperature to the surface of bamboo.The researches of the SEM of surface appearance and bonding interface show that bamboo green skin and bamboo yellow endothecium represent different instance by the low temperature. After treated, the surface of bamboo green skin appears unsmooth holes, however, the surface of bamboo yellow endothecium appears reticulation interlaced structure form. These conclusions validate the changes of Lifshitz-vander waals (LW) energy with the treatment of the low temperature to the surface of bamboo.The paper also studies the wettability attenuation situation of bamboo surface after the treatment of low temperature plasma, results indicates that the period of validity of reactive group of bamboo green skin is 4-10 days, the period of validity of active group of bamboo yellow endothecium is 6-12 days.
As a new kind of environment-protection materials, poly( L-lactic acid ) (PLLA) has a wide application in medicine, industry, national protection, et al, especiallly when it is combined with the technology of electrospinning. But the poor hydrophilicity, low speed of degradation have a bad effect on its application. In this article, poly(vinly alcohol) (PVA) was used to improve PLLA. PLLA/PVA blended or composite micro/nanofibers were prepared by the means of electrospinning. The spinning effect and fibers’properties were analyzed by apparatuses.Firstly, PLLA/PVA composite nanofibers were prepared with the self-assembled electrospinning equipment, in which two kinds of solutions were blended as the spinning solution. The proper technical parameters, which were determined by video zoom microscope and atomic force microscope (AFM), were as follows: 14%/6% of the concentration ratio of PLLA/PVA, 12kV of the spinning voltage, 0.5mL/h of the extruding speed, 18cm of the collecting distance. Well-shaped fibers were obtained with these parameters. Some chemical interaction between PLLA and PVA in the blended fiber had been proved by infrared spectrum (IR) . The incompatibility of PLLA and PVA in the nanofibers was observed using tapping and phase modes of AFM. But there were great differences among nanofibers prepared in different time. More droplets and beads appeared in the latter case. It may be caused by the change of environment and material properties. Because of the unstability of the spinning result, it couldn’t repeated, other preparation method of PLLA/PVA composite nanofibers was taken.A twin-spinneret electrospinning equipment, which had two sets of solution-extruding devices and high-voltage power supplies and a roller as the co-collecting device, was set up and the PLLA/PVA composite micro/nanofibers had been prepared with two kinds of solutions spinning separatedly. After analyzing the images of video zoom microscope and scanning electron microscope (SEM), the most suitable technical parameters were listed as follows: PLLA solution, concentration 30%, voltage 15kV, extruding speed 1.0, 0.8, 0.5, 0.2mL/h, collecting distance 15cm; PVA solution, concentration 10%, voltage 18kV, extruding speed 0.2mL/h, collecting distance 15cm; rotating speed of the roller 200r/min. And the structure, diameter distribution and surface roughness of nanofibers were analyzed by SEM and AFM. The mechanical property of composite nanofiber mats was analyzed by tension test and force-distance curves. PLLA 1.0mL/h showed the best mechanical property and PLLA 0.5mL/h was the worst. PLLA got a better adhesive ability than PVA did. Composite nanofiber mats had a great improvement on the wettability comparing with the pure PLLA nanofiber mat, which was proved by the tests of static contact angle and dynamic water adsorption. PLLA 0.2mL/h was the best. Some improvements on the thermal stability of PLLA had been made with PVA added.
ZnO materials possess excellent properties such as physics,chemic,optics and electronics as an important semiconductor material.In this thesis,ZnO micro-nanostructures with hierarchical structure were fabricated with low temperature liquid phase method.Their wettabilities were mainly discussed.In addition,ZnO micro-nanostructures were selectively grown using molecule self-assembly and photolithography techniques.The results revealed that:1.Oriented ZnO rods and micro-nanostructural ZnO spheres with hierarchical structure can be obtained through adding appropriate quantities of HF solution into the reaction solutions.When the amount of HF additives was less,H~+ played a major role to the orientation of ZnO rods;when the amount of HF additives was more,F~- was one of the main factors to tailor the microstructures of ZnO micro-nanospheres.To obtain the ZnO spheres,550-700μl HF solution(1M) should be added when the concentration of reaction solution was 0.1M;350-500μl HF additive was appropriate for 0.05M reaction solution.2.Both the reaction time and temperature have an effect on the growth of ZnO micro-nanospheres.The diameter and distribution density of spheres increased when the reaction time was prolonged up to 2 hours.When the reaction temperature was below 90℃,ZnO spheres could not grow.3.The water contact angles of the ZnO spheres films and oriented ZnO rods films are 157.1°and 151.4°,respectively.Both of them have excellent wettability photo-responsive properties.The two superhydrophobic surfaces can be transformed into superhydrophilic when irradiated by vacuum ultraviolet(VUV) for about 30 minutes,and then can be recovered to superhydrophobic when placed in dark room for about 6 days.4.The surfaces of the two ZnO different micro-nanostructures have strong adhesive force to water according to our measurement.The values were 868.3μN and 946.7μN for rods and spheres.Obviously,different microstructures can result in different adhesive forces.5.After the two surfaces of the different ZnO microstructures were modified with octadecyltrimethoxysilane(ODS),the water contact angles of them increased to 170.7° and 165.4°for ZnO spheres and rods.Also both of them have small hysteretic angles and can be reversed between superhydrophilic and superhydrophobic.6.Selective growths of ZnO microstructure were realized with organic molecule self-assembly(from bottom to up) and photolithography(from top to down) techniques. By adding some additives such as HF,Ammonium fluoride,Ammonium chloride, Ammonium nitrate,the orientation of ZnO rods can be improved when they selectively grew.Wettability of materials has attracted much interest because it will bring great convenience on our daily life as well as in many industrial and agricultural processes. Selective growth of nanomaterials is a key to realizing their practical application,such as advanced electrics,photics and MEMS devices.In this thesis,the study on the fabrication wettability of ZnO micro-nanostructures with hierarchical structure will be helpful to develop ZnO-based micro-fluidic devices.
The coal dust can not only severely damage workers ‘ healthy, but also seriously threaten safety production of coal mine. But the traditional dust falling method, which depending on water, has bad effect, especially for breathing dust. Moreover, it is easy to deteriorate working environment. Advantage and disadvantage of dust suppression method on water have been analyzed in this paper, it is concluded that foam falling dust can reduce water consumption and increase efficiency of reducing dust.Characteristics of coal dust have been comprehensive studied in the paper. For example, particle size of coal dust has been researched by Winner3001 Laser Grain Size Analyzer, and in consequence, the particle size distribution of three experimental coal dust samples have been obtained. Shape and structure of coal dust have been analyzed by scanning electron microscope, it is shown that the size of particles is uneven and the shape of particles is irregular. Wettability of coal dust has been studied by DSA100 dynamic contact angle measuring instrument, it is proved that wetting effect of mine water and distilled water is not very ideal.It is determined three foaming agents, four stabilizing agents, two wetting agents through original selection on foaming agent, stabilizing agents and wetting agent, which constituting foam dustfall agent. According to national standard GB/T7462-94 “Foaming ability measurement of surfactant–improved Ross-Miles method”, it had experimental studied on foam performance of foam dustfall agent which had different proportion by single factor experiment, and optimal analyzed experiment data through Origin data analysis software. Finally, eight foam dustfall agent formulas had been primary determined. And the wettability between eight foam dustfall agent and coal dust had also been researched. As a result, the wetting effect of foam dustfall agent is far better than mine water and distilled water. Finally, two foam dustfall agent have been settled.
Polylactic acid (PLA) fiber is a new eco-fiber, which not only owns the basic characteristics of synthetic fibers but also is a nature fiber with biocompatibility and biodegradability. Polylactic acid fiber is more competitive than other textile products which using oil as raw material in many aspects. Yet as a kind of aliphatic polyesters, it contains large numbers of esters bonds in its molecular structure, which makes it low hydrophilicity.To improve some performances of PLA fiber, lipase L3126 and Lipex100L was chose to hydrolyze ester bonds of PLA fiber in this article. Through evaluation indexes such as weight loss, drop time, dyeing performance, UV absorbency, pH value, the content of lactic acid and by means of SEM, XPS, HPLC and so on, the performance changes of PLA fiber and enzymatic solution were analyzed. Effects of plasma pretreatment to hydrolysis were also pilot studied in this paper.Technics of treatment by the two lipases were investigated to educe the optimal conditions. And treatment effect with different lipases was compared also. The results showed that the optimal conditions for lipase L3126 were determined: enzyme concentration 0.5g/L, pH 8.5, treating at 45℃for 8 hours; the optimal conditions for lipase Lipex100L were determined: enzyme concentration 10mL/L, pH 7.5, treating at 40℃for 10 hours.After dyeing with reactive black S-EO, reactive blue HN-GR and basic blue X-GB, K/S value of the treated fiber was higher than untreated fiber obviously. The scanning electron microscopy confirmed that the two kinds of lipases we chose all had effects on the polylactic acid fiber. Through XPS analysis it was indicated that after treated with lipases, the content of C descended, the content of O ascended and the content of carboxyl and hydroxyl increased. pH value of lipase solution was taken on dropping current. The hydrolysis can produce lactic acid substance in terms of UV analysis and HPLC. The action to polylactic acid fiber of lipase L3126 was better than lipase Lipex100L.Plasma pretreatment was adopted in this paper. The longer plasma treatment time and the greater discharge power and the larger discharge pressure were, the bigger UV absorbency was. Hydrolysis production analysis and the change of dyeing performance all indicated the plasma pretreatment accelerated the reaction of hydrolysis catalyzed by lipases.
Investigation on Microstructure and Properties of Cadmium-Free Silver-Based Intermediate Temperature Filler Metals
The cadmium-containing silver-based filler metals were applied extensively in the industry field because of the good properties of filler metals, but the appliance of filler metals were limited recently, because the element of cadmium was poisonous and the silver was more and more expensive, so the silver-containing 20 percent and cadmium-free of silver-based filler metals were studied. In this paper, the composition of filler metals was optimized by the method of phase graph, and the result was discussed by the distribution of temperature of AgCuZn and the distribution of phase of AgCuZn, at last, thirteen filler metals were get. The microstructure of cast filler metals, the wettability of filler metals, the properties of joints brazed with filler metals and the microstructure of interface were studied experimentally and theoretically.The studies of the microstructure of filler metals indicate that the filler metals are mainly consist of Cu-rich phase, CuZn compound, tin bronze (Cu5.6Sn compound and Cu40.5Sn11 compound), Cu3P compound or Ni3P compound and Ag solid solution. With the increasing of Sn, the proportion of each phase of filler metals is changed, and Cu40.5Sn11 compound can be observed. With the increasing of Ni, the size of tin bronze becomes smaller and smaller, and the Ni3P compound is observed; with the increasing of La, the size of microstructure of filler metals becomes smaller than before apparently, all these can effect the tensile strength of filler metals. The results of the tensile strength of filler metals indicate that when the content of Sn, Ni, La are 6.5%, 2.0%, 0.5%, respectively, the maximum tensile strength of filler metals are attained.By the experiments of wettability of filler metals, we can know that the amount of 1Cr18Ni9Ti stainless steel, which is dissolved into the welding seam, becomes more and more with the increasing of Sn; the amount of that becomes less and less with the increasing of Ni; when La is added into the filler metal, 1Cr18Ni9Ti stainless steel can be restrained dissolving into the welding seam; the amount of copper, which is dissolved into the welding seam, becomes more and more with the increasing brazing temperature. From the results of the experiments of wettability, the maximum wettability area of filler metals is attained, when the content of Sn, Ni, La are 6.5%, 2.0%, 0.3%. The maximum wettability area of filler metals on substrates of copper and 1Cr18Ni9Ti stainless steel are 351mm2, 212mm2, respectively, which are bigger than the wettability area of BAg30CuZnSn filler metal.The analysis of microstructure of joints indicates that the size of the microstructure of welding seam becomes smaller and smaller with the increasing of Ni, La, when the element of La is added into the filler metals, black compounds of silver and lanthanum are observed; From the analysis of shear strength of joints, we can know that when the content of Sn, Ni, La are 4.5%, 2.0%, 0.5%, the maximum shear strength of joints brazed with the filler metals are attained, respectively. Compared with the BAg30CuZnSn filler metals, we can know that the shear strength of joints of 1Cr18Ni9Ti stainless steel and copper brazed with filler metals, in which the content of Sn、Ni、La are 6.5%、2.0%、0.5%, respectively, is stronger than the shear strength of joints brazed with BAg30CuZnSn filler metal.
Study on Synthesis and Application Property of Polyglycerol Fatty Acid Ester as Ecological Textile Auxiliary Agent
Polyglycerol fatty acid ester is a new type of surfactant with manifold performanceswhich has developed recently,such as emulsification,solubilization,dispersion,defoaming,etc.It is used to a wide range of fields,such as food additives, petrochemical industry,health &medicine,cosmetic,plastic processing,etc.In the field of textile,the application of polyglycerol fatty acid ester is started,single species;its service performance isn’t expanded.At present,people pay attention to the environmental protection;research and development of polyglycerol fatty acid ester surfactant and their application as the textile auxiliary agent has of great significance.The raw material is glycerin,two different degree of polymerization(n=3,5) of polyglycerols were synthesized by controlling the reaction conditions(temperature,amount of catalyst,water),at the same time,selected four kinds of fatty acids,a series of new polyglycerol di-fatty acid esters were synthesized.Tested basic properties of the synthesis samples (acid value,saponification value,hydroxyl value,surface tension),and in accordance with the fatty acid value and of the sample.Test results showed that part of the performance of products reached to those of foreign products by this method. The effect of smooth,wettability,antistatic of the polyglycerol di-fatty acid esters for different fabrics were discussed,analyzed and compared the effect of different degree of polymerization,type of fatty acids,concentration of finishing liquor.Test results showed that(1)smooth:the synthesis samples were prepared into different concentration of finishing liquors,processed cotton fabric by double-dip-double-nip.The smooth of finished gray fabrics increased by 15%to 25%;(2) antistatic:the synthesis samples were prepared into different concentration of finishing liquors,processed polyester fabric by double-dip-double-nip.The sensor/friction static voltage on the surface of the finished fabric decreased obviously,the sensor/friction static voltage on the surface of polyester fabric was 4122V,After processing,its sensor/friction static voltage was 1258V,obtained good finishing effect.(3)wettability: Tripolyglycerol dioleic acid ester has the best wettability to polyester fabric.The feasibility application performance of polyglycerol di-fatty acid esters were discussed,which were added to cassava starch size in order to improve flexility of the starch film,6%concentration of cassava starch was prepared,added different amounts of polyglycerol di-fatty acid esters,poured into starch films.Results showed that pure starch films were cracked into many small pieces,which couldn’t be required to a sample specifications for testing:20cm×2.5cm,starch films joined the synthesized samples were integrated,obtained a sample specifications for testing.Tested the bending stiffness of films,analyzed and compared the effect of different degree of polymerization,type of fatty acids,amount of additive for flexility of the film.Finally,obtained molecular structure information of good effect of Polyglycerol di-fatty acid ester.