可酸化性与酸化度作为高浓度有机废水厌氧酸化指标的研究

研究了糖蜜酒精废液的酸化规律,在此基础上定义了可酸化性(V C)与酸化度(α)的概念,作为评价高浓度有机废水可酸化特性以及实际酸化效果的指标.实验结果表明,糖蜜酒精废液的可酸化性为0 71.酸化过程产生的挥发性脂肪酸(VFA)达3 710 9mg·L- 1 (以COD计)以上时,会对酸化反应本身形成反馈抑制.故测定较高浓度有机废水的可酸化性时,应采取稀释的方法降低废水浓度和酸产量。

部分酸化磷肥肥效及适宜酸化度研究

通过盆栽试验探讨部分酸化磷肥的适宜酸化度及肥效。在湖北省黄棕壤上施用部分酸化磷肥对大麦的生长发育具有较好的促进作用，酸化度以５０％～７５％较好，与完全酸化的过磷酸钙具有同等的增产效果。

高浓度有机废水可酸化性与酸化度的测定

以测定高浓度有机废水的可酸化性和酸化度为目的,研究了蔗糖-蛋白胨人工配水的酸化过程。实验结果表明,蔗糖-蛋白胨人工配水的可酸化性的计算值为0.80;振荡条件下COD为1065～31950mg/L的废水的酸化度为100%,COD为426100～63900mg/L的废水的酸化度介于79%～90%;静态条件下COD为1065～63900mg/L的废水酸化度介于64%～99%;酸化过程中通过振荡培养,改变传质条件,可以提高酸化速度,缩短可酸化性测定时间。

预酸化度对柠檬酸废水厌氧处理的影响

以柠檬酸废水为研究对象，研究了预酸化度对上旋流厌氧反应器处理性能的影响。研究结果表明，预酸化度对上旋流厌氧反应器系统的COD去除率、出水VFA、污泥增长量、产气量有明显的影响。随着预酸化度的提高，可以提高厌氧系统的COD去除率，降低出水VFA，增加沼气产量，但降低了颗粒污泥增长的速度。在实际工程应用中，控制预酸化度在20％～30％可以保持厌氧系统稳定高效的COD去除效果，同时保证颗粒污泥的快速增长。

猪饲料酸化度的选择

二十年前的19世纪80年代，营养学家们就意识到了仔猪教槽料和断奶日粮配方中所谓的酸结合因子的重要性，此后，这方面取得了长足发展。饲料配方中考虑负电解质平衡的思路不仅可用于小猪料，其他多种猪料中也可予以应用。

胆红素生产中的脱脂方法与酸化度研究

为提高胆红素生产效益,采取正交试验优化筛选脱脂方法(双层纱布法、石油醚洗涤法、混合法)和酸化度(pH5.0、pH5.5、pH6.0),结果表明:脱脂方法和酸化度对胆红素提取差异高度显著(P<0.01),影响度脱脂方法>酸化度;在双层纱布过滤、酸化至pH5.0时萃取的常规条件下,胆红素的粗制品收率0.0923 g/L、纯度36.18%,折合纯品收率0.0333 g/L;在混合法脱脂、酸化至pH5.5时萃取的条件下,胆红素的粗制品收率0.6122 g/L、纯度52.05%,折合纯品收率最高,达0.3186 g/L。

乳酸菌产酸特性研究

对比研究了嗜热性乳酸菌、乳球菌的产酸特性以及影响后酸化的因素。结果显示,乳球菌最大产酸量为64.40T～72.70T;嗜热性乳酸菌的最大产酸量为106.80T～294.20T。德氏乳杆菌保加利亚亚种、唾液链球菌嗜热亚种的最大产酸速率为20.750T/h、24.570T/h。乳酸乳球菌乳酸亚种、乳酸乳球菌乳油亚种、乳酸乳球菌乳酸亚种丁二酮变种的最大产酸速率分别为7.650T/h、6.520T/h、9.650T/h。优良的菌株特性、低温贮存、较低的最终发酵酸度是保证乳酸菌低后酸化的有效措施。

提高渣油掺炼率催化裂化催化剂的开发

在研制提高鲁宁管输油减压渣油掺炼率的重油催化裂化催化剂时,考察了大孔活性基质的制备方法以及分子筛活性组元的选择。研究结果表明,使用浅度酸化的方法可以增加基质中大孔所占比例;具有丰富二级孔的超稳分子筛可与活性基质相匹配,使催化剂具有梯度的孔分布。研制出的催化剂的小试评价结果表明,该催化剂对鲁宁管输减压渣油的质量掺入率为35％的重油具有很好的裂化作用,具有水热稳定性好、轻质油收率高、焦炭产率低等特点。

Influencing factors analysis of hard limestone reformation and strength weakening under acidic effect

Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way to control the hard limestone roof.In this study,the effects of various factors on the reaction characteristics and mechanical properties of limestone were analyzed.The results show that the acid with stronger hydrogen production capacity after ionization(pK_(a)<0)has more prominent damage to the mineral grains of limestone.When pKa increases from−8.00 to 15.70,uniaxial compressive strength and elastic modulus of limestone increase by 117.22%and 75.98%.The influence of acid concentration is manifested in the dissolution behavior of mineral crystals,the crystal defects caused by large-scale acid action will lead to the deterioration of limestone strength,and the strength after 15%concentration reformation can be reduced by 59.42%.The effect of acidification time on limestone has stages and is the most obvious in the initial metathesis reaction stage(within 60 min).The key to the strength damage of acidified limestone is the participation of hydrogen ions in the reaction system.Based on the analytic hierarchy process method,the influence weights of acid type,acid concentration and acidification time on strength are 24.30%,59.54% and 16.16%,respectively.The research results provide theoretical support for the acidification control of hard limestone roofs in coal mines.

内循环厌氧反应器处理制浆造纸废水的效能及影响因素

介绍了处理制浆造纸废水的内循环厌氧反应器工程实例,考察了有机物(COD和挥发性脂肪酸VFA)去除效果及其影响因素(进水容积负荷、进水预酸化度、环境条件)。在平均进水COD为1 562.1 mg/L、平均进水VFA质量浓度为684.0 mg/L、平均水力停留时间为3.7 h条件下,平均COD和VFA去除率分别达到53.7%和77.9%。既保持较高COD去除率又充分发挥反应器处理能力的最佳进水COD容积负荷为11.8 kg/(m3·d)。温度(32.2~39.5℃)、碱度(以CaCO3计)(1 712.2~2 683.5 mg/L)均在适宜范围内,pH(7.5~7.9)略高于适宜范围。进水酸化度不足和水力停留时间较短是进一步提高COD去除率的主要限制因素,可通过适当延长预酸化池和内循环厌氧反应器的水力停留时间来解决。

IC反应器处理制浆废水的新探索

将硫酸盐法(KP)苇浆稀黑液与碱性过氧化氢机械浆(APMP)制浆废水按一定比例混合,用IC反应器进行厌氧处理。结果表明:APMP废水和KP法苇浆稀黑液按一定比例混合后进行厌氧处理是可行的,在36℃±1℃的条件下,容积负荷为12～15kgCOD/m^3·d时,COD_(Cr)的去除率为65%左右,BOD_5的去除率在85%左右,产气率为0.40～0.42m^3/kgCOD_(Cr)。

两相厌氧工艺快速启动运行及其群落结构特征研究

采用连续搅拌反应器进行产酸及产甲烷分相培养,实现两相厌氧快速启动及稳定运行.监测挥发性脂肪酸、pH、ORP、COD去除率及酸化度反应运行状况.同时进行扫描电镜及16SrDNA考察两相污泥性能差异.结果表明:在产酸与产甲烷分相培养过程中,随进水负荷的增大,产酸相COD去除率从初期的68%降低到12%,当进水负荷稳定在10kg/m3·d时,酸化率在45%左右,产酸相始终呈丙酸型发酵.产甲烷相COD去除率在75%~80%.产酸相污泥颜色从开始的灰黑色逐渐变化为灰褐色、淡黄色,最后为乳白色,菌群形态主要为短杆菌、芽孢菌及丝状菌.产甲烷相污泥始终呈灰黑色,菌群形态主要为甲烷八叠球菌.根据16SrDNA测序结果,产酸相优势菌为Enterobacteriaceae(肠杆菌属),Bifidobacterium(双歧杆菌科),Corynebacterium(棒杆菌属),Bacteroidetes(拟杆菌),Clostridium sensu stricto(梭状假胞杆菌属).产甲烷相优势菌为Anaerolineaceae(厌氧绳菌属),Aminivibrio(氨基酸降解菌),Mesotoga(弥索袍菌属),Methanobacterium(甲烷杆菌属),Methanosarcina(甲烷八叠球菌).

Environmental Changes Analysis of Hongjiannao Lake During Recent Fifty Years——Based on the Data of Lake Sediments

Particle size, the contents of carbonate and TOC were analyzed on lake sediments from a short core in Hongjiannao Lake to discuss the environmental changes during the past decades. On the basis of the records in lake sediments and comparison with the meteorological data of Yulin region, the environmental changes in Hongjiannao Lake were approximately divided into two stages. In stage A （1957 -1996）, the lake evolution and the environmental change were mainly influenced by natural factors. It contains three sub-stages： A1 （1957-1969）, a period of lake expansion, A2 （1969-1990）, a stable period with high lake levels, and A3 （1990 -1996）, a period of gradual extraction of the lake. In stage B （1996 -2005）, the lake area still keeps diminishing. During this period, organic matter increased rapidly due to the input of nutrient elements in the catchment. The carbonate content, however, decreased. As the precipitation was decreasing and the temperature was increasing, the decrease of carbonate content could not be explained by either temperature or precipitation change.

The Initial Reactions of HaPO4 and NaH2PO4 Supported on Silica： A Joint Experimental and Theoretical Study

A combination of X-ray powder diffraction, thermogravimetric analysis, diffuse reflection infrared Fourier transform, and ^31p magic-angle spinning nuclear magnetic resonance techniques with density function computation was used to elucidate the products and mecha- nism of the reactions among silica, H3PO4, and NaH2PO4 during the preparation of silica supported H3PO4 and NaH2PO4 catalysts. The spectral test results indicate that besides polyphosphoric acid, silicon phosphates on silica supported H3PO4 are also formed. On silica supported NaH2PO4 only sodium polyphosphates are present. Density functional theory （DFT） simulations indicate that in the initial stage, reaction of H3PO4 with silanol groups on the silica support is more favorable than that between H3PO4 itself. In contrast, dimerization and trimerization of NaH2PO4 are predicted to be the predominant initial reactions for the silica supported NaH2PO4 catalyst.

Nano-porous Composites Based on Liquid： Synthesis, Characterization, Esterification Heteropolyacid Functionalized Ionic and Catalytic Performance in

Fhnctionalized ionic liquid samples （bmim-PW12） were synthesized by 1-butyl-3-methyl- imidazolium bromide （bmimBr） and 12-phosphotungstic heteropolyacid （PW12）. The samples were annealed at 100-450 ℃ and were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, thermal gravity-DTG, brunauer emmett teller, and NHa-temperature programmed desorption. The results showed that the bmim-PW12 samples were crystal and maintained intact Keggin structure. The organic parts of those samples were partly decomposed at a temperature more than 350 ℃. The sample annealed at 400 ℃ exhibited nano-porous structure, strong acidity, and excellent catalytic activity on the esterification of n-butanol with acetic acid. The higher ester yield was obtained when the mass ratio of catalyst over the reactants amount was 5% for bmim-PW12 catalyst annealed at 400 ℃.

铝对香蕉水分及营养成分吸收的影响

5种香蕉的离体植株于温箱、酸性溶液中培养40天,温箱温度接近作物生长地区。以蠕动泵连续施用不含铝(对照)和含78.5微摩尔/升铝的稀释溶液于幼嫩植株。每周调查2次植株吸收水分和营养成分的情况,同时监控水平酸化度。结果发现。

In vitro Dissolution and Pharmacokinetics in Beagle Dogs of a Self-Emulsifying Formulation of Tretinoin

Aim In vitro dissolution test and pharmacokinetics in beagle dogs wereconducted to assess the formulation of tretinoin in self-emulsifying systems. Methods Theconcentrations of tretinoin were determined by HPLC. A crossover study was performed in four fastingbeagle dogs with the formulation of self-emulsifying systems and commercial capsules. Results Theresults showed that the dissolution rate in 15 min of tretinoin in self-emulsifying systems washigher than 80% while that of the commercial capsules was lower than 5% . The area under the plasmaconcentration-time curve (AUC) of the self-emulsifying formulation was significantly higher andC_(max) was approximately two times greater than those of commercial capsule, respectively, Inaddition, the time taken to reach peak was shorter (2 h to 1.25 h) for self-emulsifying formulationof tretinoin. Conclusion The self-emulsifying drug delivery systems.can significantly increasetretinoin in vitro dissolution and in vivo absorption.

Optimization of brine leaching of metals from hydrometallurgical residue

An orthogonal array,L16(45),was used to examine the effects of four parameters,including NaCl concentration,H2SO4 concentration,temperature and pulp density,on the recovery of Cu,In,Pb and Zn from a hydrometallurgical residue via brine leaching.The results show that temperature of leaching solution has a significant effect on the recovery of Cu,In and Zn,while H2SO4 concentration has an obvious influence on these metals extraction.Both pulp density and NaCl concentration significantly affect Pb extraction.Based on the orthogonal array experiments,the optimum conditions for the extraction of Cu,In,Pb and Zn from hydrometallurgical residue are NaCl concentration of 250 g/L,H2SO4 concentration of 1.00 mol/L,temperature of 85℃,and pulp density of 100 g/L.After 1 h of treatment at these optimum conditions,over 91% of the metals are extracted from the residue.Brine leaching is therefore suitable for the recovery of metals from hydrometallurgical residues.

Pressure leaching of zinc silicate ore in sulfuric acid medium

Zinc silicate ore was characterized mineralogically and the results showed that zinc exists mainly as hemimorphite and smithsonite in the sample.Sulfuric acid pressure leaching of zinc silicate ore was carried out to assess the effect of particle size,sulfuric acid concentration,pressure,reaction time and temperature on the extraction of zinc and the dissolution of silica.Under the optimum conditions employed,up to 99.25% of zinc extraction and 0.20% silica dissolution are obtained.The main minerals in leaching residue are quartz and small amounts of undissolved oxide minerals of iron,lead and aluminum are associated with quartz.

Behavior of calcium oxalate in sodium aluminate solutions

The stability of calcium oxalate is critical for the removal of sodium oxalate from sodium aluminate solutions.This studyinvestigated the behavior of calcium oxalate in sodium aluminate solution containing sodium carbonate.Results show that calciumoxalate can be converted to tricalcium aluminate hydrate(TCA)and calcium carbonate in sodium aluminate solution and sodiumcarbonate solution,respectively.Elevating temperature,extending residence time,or increasing caustic soda concentration enhancesthe conversion ratio of calcium oxalate in sodium aluminate solution;as a consequence,anti-causticisation occurs.Stability ofcalcium-containing compounds in sodium aluminate solution containing sodium carbonate differs from that in sodium aluminatesolution or sodium carbonate solution.Na2CO3in aluminate solution accelerates the transformation of calcium oxalate;thus,aluminais lost because of4CaO·Al2O3·CO2·11H2O and TCA formation.Calcium carbonate,4CaO·Al2O3·CO2·11H2O and calcium oxalatecan change into TCA in sodium aluminate solution at elevated temperature.Calcium oxalate remains relatively stable in dilutealuminate solution within a short residence time at low temperature.Thus,a novel process for removal of sodium oxalate by limecausticisation was presented and employed in an alumina refinery in China.