| Along with the rapid development of modern industry,the environmental pollution is more and more serious,so people attach highly importance to environmental protection.Compared with mineral lubrication oil,synthesized ester lubrication oil has many excellent properties,i.e.the property of high temperature and low temperature,high viscosity index,heat-oxidation stability,fine lubricant characteristic,low volatility,excellent thermal stability,radiation-resistant characteristic, physiological harmlessness and easy biodegradability in the natural environment,therefore,it is widely used in all kinds of aviation,spaceflight,military affairs and civilian.Environmental pollution isn't ignorable because a great deal of used ester lubrication oil can't be reclaim and conventional synthesis method brings outgrowth and organic solvent.Thereby,the comprehensive systemic studies about green synthesis photodegradation and influence of ester lubrication oil on soil zoology are of vital importance to theory and realism.The microwave synthesis of polyol esters,di-esters without organic solvent and the biosynthesis of dodcanol capriate and the photodegradation and influence of them on soil zoology were investigated in the dissertation.Under microwave irradiation the polyol esters of lubricating oil were synthesized without organic solvent by the reaction of trimethylolpropane(TMP) or pentaerythritol(PE) or dipentaerythritol(di-PE) with C5 to C9 carboxylic acids.By comparing with the conventional synthetic method,the results show that the reaction time under microwave irradiation is largely shortened and the reacting velocity increases ten to fifteen times for TMP tri-ester,and the yields of TMP tri- caprylate and TMP tri- nonanoate are respectively increased 11%and 13%.For PE esters the reaction time under microwave irradiation also is largely shortened and the reacting velocity increases ten to eleven times.The yields of PE quadri-caprylate and PE quadri- nonanoate are respectively increased 12%and 10%.Optimizations of a series of reactions about PE and TMP with C5-C9 straight-chain fatty acid were investigated without organic solvent under microwave irradiation.For TMP esters,the best microwave power was between 280 W and 320 W.The reaction time was 6～10 min and the yields were 81%～96%.For PE esters,the best microwave power was 300 W～320 W.The reaction time was 8.5～11 min and the yields were 85%～98%.The best synthetical conditions of di-PE with C5 to C8 carboxylic acids were investigated without organic solvent under microwave radiation.The best molar ratio of C5 to C8 carboxylic acids vs di-PE was 8: 1.The best microwave power was 300W～320W.The best composite catalyst was selected,and the ratio of composite catalyst(vitriol oil vs p-toluene sulphonic acid) was from 1:2.5 to1:3.0.The yields were at least 93%within 9～10min.Their viscosity coefficients were determined by Ubbelohde viscosimeter.With the increase of carbon atom number of carboxylic acids,their esterifiable temperatures and viscosities gradually went up.Under microwave irradiation the di-ester of lubricating oil were synthesized without organic solvent by the reaction of hexane diacid or azelaic acid or sebacic acid or o-phthalic acid with isooctyl alcohol or dodecanol.The results showed that the best microwave power was 300W～3320W,the reaction time of diisooctyl adipate,diisooctyl azelate and diisooctyl sebacate was 8～9 minute and the yields were 91%～95%.The reaction time of didodecyl adipate,didodecyl azelate and didodecyl sebacate was 4～9 minute and the yields were 95%～97%.Their crystal points have been determined first.All structures of di-ester and polyol ester have been characterized by 1H NMR,13C NMR and IR spectra,and their refractive indexes,viscosity coefficients and colors and luster have been determined.In comparison with the conventional and industrial method,microwave-synthesized method has many advantages of fast reacting velocity,high yield,low energy consuming,few outgrowth,good colors and quality and decreasing environmental pollution by reason of organic solvent.Thereby,it is a perfect green synthetical method and it may provide a new research orientation for traditional technology improvement of ester lubricating oil.The mechanism and direct effect of ethylene on lipase activity have been studied.The results showed that the lipase activity increased in ethylene of lower concentrations and the highest percent was 13.0%when the ethylene concentration was 0.9834 mmol·L-1.The lipase activity decreased in ethylene of higher concentrations and the highest percent was 24.50%when the ethylene concentration was 7.9669 mmol·L-1.The optimum temperature of the lipase in the presence of ethylene increased by10～15℃compared to that in the absence of ethylene.The optimum pH of the lipase was 7.5 in the presence or absence of ethylene.When pH was 7.9 the lipase activity in the presence of ethylene increased greater and reduced when pH was 4.5～7.5,8.5 and 9.5～11.To compare with contrast,the UV absorption and fluorescence emission intensities of the lipase in the presence of ethylene were enhanced markedly,and its fluorescence polarization,specific rotatory power at 30℃and the viscosity at 14℃in the presence of ethylene declined obviously.Differential scanning calorimetry was adopted for studying conformational transition of the lipase in the presence or absence of ethylene.The results revealed that the peak temperature of reversible endotherm of the lipase in the presence of ethylene was higher than that of the contrast and the enthalpy was lower than that of the contrast at a lower temperature,and the peak temperature of nonreversible endotherm and the enthalpy in the presence of ethylene were lower than that of the contrast at a higher temperature.The mechanism and effect of ethylene on esterifiable activity of lipase and its conformation have been investigated in organic solvents,taking the example of lipase-catalyzed esterification of capric acid and dodcanol.The results showed that the lipase activity increased in the presence of ethylene of lower concentrations and the highest percent was 39.23%when the ethylene concentration was 247.93nmol.L-1.The lipase activity decreased in the presence of ethylene of higher concentrations and the highest percent was 27.64%when the ethylene concentration was 14644.23nmol.L-1.The lipase activity in cyclohexane and n-hexane increased and decreased in isooctane in the presence of ethylene.The optimum esterifiable temperature of the lipase in the presence of ethylene decreased by 15℃compared to that in the absence of ethylene.The lipase activity was activated by ethylene in lower substrate concentration and inhibited by ethylene in higher substrate concentration.These actions were reversible.The esterification reaction had the inhibition effects of both substrates.The kinetics of the reaction was consistent with the Ping-Ping Bi-Bi mechanism,which is characterized by inhibition by both acid and alcohol.To compare with contrast,the viscosity at 14℃,and specific rotatory power at 25℃and fluorescence polarization of the lipase in the presence of ethylene declined obviously;and its fluorescence emission intensities and the distance between extremum value of ultraviolet second-derivative spectroscopy were enhanced markedly,and their peak locations changed in the presence of ethylene.The DSC revealed that the peak temperature of nonreversible endotherm and its enthalpy of the lipase in the presence of ethylene were higher than that of the contrast.These results prove adequately that ethylene can directly influence not only the esterifiable and hydrolytic activity of the lipase but also the microcosmic environment and conformation of the lipase.The mechanism that ethylene acts on the lipase probably is that ethylene changes the microcosmic environment of the lipase and embeds the lipase inside to drive the conformational transition of the lipase.This also prove organic gaseous small molecule can effect on the biosynthesis of ester and extend its study scope.The result is the very significance for chemistry biology science.The photodegradation of di-PE hexa-heptylate,TMP tri-heptylate and diisooctyl o-phthalic ester under UV were investigated,using anatase nano-TiO2 as photocatalyst.The photodegradation results of the concentration of nano-TiO2 and H2O2,PH,organic solvents,and the analysis of reaction kinetics as follows:Compared with the comparison,anatase nano-TiO2 can markedly accelerate the photo -degradation of di-PE hexa-caproate and TMP tri-heptylate.When nano-TiO2 concentrations were respectively 1.26g·L-1 and 1.24 g·L-1 and ultraviolet radiation time was 20 min,their degradation effects were the best,and the degradation percents of di-PE hexa-caproate and TMP tri-heptylate were respectively 93.07%and 95.8%and respectively increased about 61%and 48%than their contrasts.Effect of pH on the photodegradation of di-PE hexa-caproate was obvious and was the best in acidity and neutral conditions,but weak acidity and alkaline conditions was not advantageous for its photodegradation.For TMP tri-heptylate,the most suitable pH was neutral and weak alkaline. The effect was the best.Peroxide of hydrogen(H2O2) can promote photodegradation of di-PE hexa-caproate and TMP tri-heptylate.When the concentration of H2O2 was 2mol·L-1～3 mol·L-1,the photodegradation percent sharp rose and reached 95.92%and the photodegradation percent increased about 23%than the contrast.When the concentration of H2O2 was higher than 3 mol·L-1, the increase of photodegradation percent was slow.For TMP tri-heptylate,when the concentration of H2O2 was 3 mol·L-1,the degradation effect was the best and the percent increased about 9%by comparing with the contrast.Effect of organic solvent on the photodegradation of di-PE hexa-caproate and TMP tri-heptylate was significantly.For di-PE hexa-caproate,the order of the best photodegradation effect in four organic solvents was:isooctane＞acetone＞anhydrous ethanol＞dichloromethane.Thus,the best solvent of photodegradation was isooctane.For TMP tri-heptylate,the order of the best photodegradation effect in five organic solvents was:acetone alcohol- water solution＞methanol＞isooctane＞xylene＞.The best solvents of photodegradation were acetone and alcohol -water solution.The experimental results of the dynamics show that the kinetic equation of photodegradation of the concentration of nano-TiO2 and H2O2,PH,organic solvents for di-PE hexa-caproate,TMP tri-heptylate and diisooctyl o-phthalic ester conform to a one-order dynamics rule.Higher concentration of nano-TiO2 can restrain the photodegradation of di-PE hexa-caproate,TMP tri-heptylate and diisooctyl o-phthalic ester.When the concentrations of nano-TiO2 respectively were 1.49 g·L-1,2.98 g·L-1 and 1.49 g·L-1,the velocity constants of di-PE hexa-caproate,TMP tri-heptylate and diisooctyl o-phthalic ester were the highest and the half- life were the shortest. Compared with the comparison,their half lifes were respectively shortened three times,thirty times and four times.The velocity constant of dipentaerythritol hexa-caproate was the highest in acidity conditions.The velocity constants of TMP tri-heptylate and diisooctyl o-phthalic ester were the highest in alkaline condition.Peroxide of hydrogen on the photodegradation dynamics of TMP tri-heptylate and diisooctyl o-phthalic ester showed two effects.0.65 mol·L-1 H2O2 showed a strong photosensitizing effect.But along with the increase of concentration of H2O2,the photosensitizing effect showed more and more weak.High concentration of H2O2 showed obvious photoquenehing effect.For di-PE hexa-caproate,when the concentration H2O2 is in the range of 0～2.61 mol·L-1,the photosensitizing effect was more and more strong with the increase of concentration of H2O2.The velocity constants of TMP tri-heptylate and diisooctyl o-phthalic ester were the highest in acetone and the half- life were the shortest.By the primary analysis of the infrared spectra and the UV absorption spectra of the photodegradation outcomes of di-PE hexa-caproate,TMP tri-heptylate and diisooctyl o-phthalic ester,the mechanisms of their photodegradations with nano-TiO2 or without nano-TiO2 were different and there were intermediates of hydroxy hydrogen peroxide and small molecule peroxide in photodegradation outcomes.For di-PE hexa-caproate and TMP tri-heptylate,the photodegradation mechanism without nano-TiO2 was possibly that the ester bond first cut and became alcohol and carboxyl acid as well as little peroxide intermediate,afterwards,they were oxidized further into a lot of peroxide intermediates,and finally cut the peroxide bond and came into being small molecule alcohol and aether.The photodegradation mechanism with nano-TiO2 was possibly that the peroxide first was produced,then cut the peroxide bond and the ester bond and became small molecule alcohol and the peroxide so as to be oxidized further into alcohol and aether of low molecular weight. For diisooctyl o-phthalic ester,the photodegradation mechanism with nano-TiO2 or without nano-TiO2 was opposite with those of dip-PE hexa-caproate and TMP tri-heptylate with nano-TiO2 or without nano-TiO2.The photodegradations of PE quadri-valerate and diisooctyl o-phthalic ester under the UV were investigated,using nano-ZnO as photocatalyst.The research results of photocatalytic degradation of the concentration of nano-ZnO and H2O2,PH,reaction time,initial concentration of the ester and the analysis of reaction kinetics as follows:Compared with the comparison,nano-ZnO can markedly accelerate the photodegradation of pentaerythritol quadri-valerate and diisooctyl o-phthalic ester.Considering degradation percent and the cost,the best concentration of nano-ZnO was 14.23 mol·L-1.The photodegradation effect of pH on PE quadri-valerate and diisooctyl o-phthalic ester was different.For diisooctyl o-phthalic ester, the degradation percent increased with pH enhancing from strong acidity to weak acidity and neutral condition.When pH was 6.5,the photodegradation effect was the best.For PE quadri-valerate,the degradation percent monotonously descended with pH enhancing from strong acidity to alkalescence. Thus,the degradation percent was the highest in strong acidity condition.Peroxide of hydrogen on the photodegradation of PE quadri-valerate showed obvious photosensitizing effect.When the concentration of H2O2 was 2.9382 mol·L-1,the degradation percent was 60.48%and increased 87.9% than the contrast.Moreover,the photodegradation of peroxide hydrogen on diisooctyl o-phthalic ester has two effects.When the concentration of H2O2 was in the range of 0.9794 mol·L-1～1.96mol·L-1,it showed obvious photosensitizing effect.When the concentration of H2O2 was 0.9794 mol·L-1,the degradation percent was the highest and increased 43.96%than the contrast. When the concentration of H2O2 was 4.897 mol·L-1,it showed obvious photoquenehing effect.The best concentration ratio of photocatalyst and reactant could make that the degradation percent was the highest.When the concentration of nano-ZnO was11.66 g·L-1 and the concentration of PE quadri-valerate was in the range of 668 mg·L-1～1002.0mg·L-1,the degradation percent was the highest.When the concentration of nano-ZnO was11.53 g·L-1 and the concentration of diisooctyl o-phthalic ester was in the range of 75.2 mg·L-1～150.2mg·L-1,the the degradation percent was the highest Along with the photodegradation time prolonging,the degradation percent of PE quadri-valerate and diisooctyl o-phthalic ester gradually increased.The degradation percent of diisooctyl o-phthalic ester reached 97.35%in 10min.And when the photodegradation time exceeded 20min,the degradation percent of PE quadri-valerate was 35.03%～38.59%and it was reposeful.The results of the dynamics show that the kinetic equations of the photodegradation of the concentration of nano-ZnO and H2O2,PH for PE quadri-valerate conform to a one-order dynamics rule.Effect of pH on the photodegradation dynamics of PE quadri-valerate was remarkable.The velocity constant in acidity conditions was the highest.The velocity constant in alkaline conditions was small and the half life was prolonged four times than that in acidity conditions.Effect of nano-ZnO concentration on the photodegradation dynamics of PE quadri-valerate was also notable. Along with the increase of nano-ZnO concentration,the velocity constant also increased and it was higher than its contrast.When nano-ZnO concentration was 12.49 g·L-1,the velocity constant was the highest and the half life was the shortest.In the testing concentration of 1.1 mol·L-1～5.8 mol·L-1 H2O2,the velocity constant was higher than its contrast.This indicated that H2O2 on the photodegradation of PE quadri-valerate had obvious photosensitizing effect.When the concentration of H2O2 was 3.2625 mol·L-1,the half life was the shortest and it was shortened four times than the contrast.But going on the increase of H2O2 concentration,the half life prolonged.By the primary analysis of the infrared spectra and the UV absorption spectra of the photodegradation outcomes of PE quadri-valerate,the mechanisms of their photodegradations without photic-catalyzer was likely to the peroxide first was produced,then cut the peroxide bond and the ester bond and became small molecule alcohol and the peroxide so as to be oxidized further into alcohol and aether of low molecular weight. The adsorption properties in mineral flavicant soil and gray-brown purple soil,and the change of soil microbes and microbial biomass nitrogen(MBN) in calcic-purple soil were studied by selecting TMP tri-heptylate as the representative of lubrication oil contamination.Adsorption kinetics and thermodynamic experiments showed that the adsorption in them was a fast process, 75.61%and 69.37%of the maximum adsorption in the two soils were respectively completed in the first twenty minutes,followed by a gradual decline,and an equilibrium was eventually reached in about 40 minutes.Thus the adsorption equilibrium time was short.This revealed that after TMP tri-heptylate went into the soil,the part of TMP tri-heptylate was fleetly fixed on the soil.This adsorption was of vital importance to late transfer and biodegradability.The isothermal adsorption data were fitted by both Freundlich equation and Langmuir equation and the results showed that Langmuir equation described the adsorption characteristics better than the Freundlich equation.The maximum adsorption capacities were obtained from the Langmuir equation,which were 12.99mg.g -1and 17.45 mg.g-1 respectively for flavicant soil and gray-brown purple soil.The result of soil microbe quantity and microbial biomass nitrogen(MBN) in calcic-purple soil indicated that the effect of TMP tri-heptylate on soil microbe quantity and MBN was very remarkable.The effect was different with different time and different concentration of TMP tri-heptylate.Compared with the comparison,the bacteria quantity rose with time at each concentration tested before 15 day.Along with test time prolonging,the bacteria quantity in the soil treated with 10.0 mg.kg-1 revealed stimulation-inhibition- stimulation effect,while that treated with 100.0mg.kg-1 had certain inhibitory effect,and that treated with 502.0mg.kg-1 became stimulatory. During 15 day～30 day,exception for that treated with 502.0mg.kg-1 keeping the rise and having stimulation effect,the bacteria quantity at the other concentration all descended.Before 28 day tested,the effect of TMP tri-heptylate at each concentration tested on fungi population was inhibition.In particular,before 5 day tested,the inhibitory effect was more and more strong with the concentration increase of TMP tri-heptylate.During 5 day～30 day,the rise speed of fungi population was fast with time prolonging.During 28 day～30 day,fungi population treated with the concentration of 10.0mg.kg-1 and 502.0mg.kg-1 was higher than its contrast and showed stimulation effect.Compared with the comparison,the actinomyce population treated with 10.0mg.kg-1 gradually increased with test time prolonging before 15 day,and the effect was firstly inhibition and then stimulation.The highest percent of stimulation was 33.7%.The effect of TMP tri-heptylate on the soil actinomyce population treated with 100.0mg.kg-1 was stimulation-inhibition- stimulation. The stimulation percent was the highest in first day.But the inhibition percent was biggest in fifth day.The effect of treated with 502.0 mg.kg-1 was inhibition at the beginning and stimulation later. During 15 day～30 day,the effects at each concentration on actinomyce population were stimulation. Compared with the comparison,exception for that treated with the concentration of 10.0mg.kg-1 was higher than its contrast before two days,microbial biomass nitrogen(MBN) at the other concentration tested was lower than its contrast.After 15 day tested,MBN at each tested concentration was higher than its contrast.
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