生物有机肥在果树上的应用效果研究

为提高果实品质,改良果园土壤,本试验研制开发了一种生物有机肥,在苹果、李、桃、葡萄上进行了田间对比试验。结果表明：生物有机肥与生产上习惯施用的有机肥相比,均有促进树体生长发育、提高产量、提高果实品质的作用。它表现在果树叶片浓绿、肥大,果实风味变浓、适口,着色艳丽;生物有机肥还对树体养分含量有调节作用,抑制由树体营养过剩...     

Crystal structure and disorder in Poly(l-lactic acid) δ form (α′ form) and the phase transition mechanism to the ordered α form

Crystal structure of poly(l-lactic acid) (PLLA) α′ form (or the newly-termed “δ” form) has been analyzed on the basis of the X-ray diffraction data. The oriented δ form was obtained by stretching and annealing the melt-quenched sample at ca. 100 °C. The unit cell parameters were a = 10.80 Å, b = 6.20 Å, c (fiber axis) = 28.80 Å and α = β = γ = 90°. As seen from the lack of even-numbered 00l reflections (002, 004, ..) except the 0010 reflection, the chain conformation of the δ form was found to be more remarkably disordered than that of the regular α form. As already reported, the α form takes the (10/3) helix with approximately 2₁ screw symmetry although, more strictly speaking, this screw symmetry is not actually existent. The δ form does not possess any symmetry along the chain axis although the local torsional angles are not very much different from each other. As for the chain packing structure, the two different possibilities were assumed in the structural refinement procedure: (i) the corner and center chains direct upward and downward along the chain axis, respectively, just like the case of regular α form (alternate packing mode) and (ii) the upward and downward chains are located at the same lattice site at 50% probability (statistically-disordered packing mode). The structure analysis using the Bragg reflections suggested the preferability of the model (i). The diffuse and streaky lines were observed along the layer lines, originating from the relative-height disorder between the neighboring chains in the δ form. The X-ray diffuse scatterings coming from the various types of the disordered structure have been simulated, among which the disordered multi-domain structure model was found to be the most plausible model, where the domains constructed by the alternate arrangement of upward and downward chains are gathered together with the mismatch in the relative height between the neighboring domains. In this way the disorder-to-order phase transition from the δ to α form was found to occur through the conformational ordering of the chains accompanied with the chain packing regularization as well as the matching of the neighboring domain height to give a large single domain of the α form.     

Biodiesel production using supercritical methanol/carbon dioxide mixtures in a continuous reactor

Fatty acid methyl esters (biodiesel) were produced by the transesterification of triglycerides with compressed methanol (critical point at 240 °C and 81 bar) in the presence of solid acids as heterogeneous catalyst (SAC-13). Addition of a co-solvent, supercritical carbon dioxide (critical point at 31 °C and 73 bar), increased the rate of the supercritical alcohols transesterification, making it possible to obtain high biodiesel yields at mild temperature conditions. Experiments were carried out in a fixed bed reactor, and reactions were studied at 150-205 °C, mass flow rate 6-24 ml/min at a pressure of 250 bar. The molar ratio of methanol to oil, and catalyst amount were kept constant (9 g). The reaction temperature and space time were investigated to determine the best way for producing biodiesel. The results obtained show that the observed reaction rate is 20 time faster than conventional biodiesel production processes. The temperature of 200 °C with a reaction time of 2 min were found to be optimal for the maximum (88%) conversion to methyl ester and the free glycerol content was found below the specification limits.     

苄基磺酸化MCM-41介孔分子筛的合成、表征及催化酯化性能

MCM-41介孔分子筛先后与苄基氯和氯磺酸接枝反应,得到苄基磺酸介孔分子筛(SBM)。通过X射线多晶衍射(XRD)、氮气吸附脱附、红外光谱(IR)、有机元素分析、扫描电镜(SEM)等方法对所得样品进行了表征。研究结果表明,MCM-41表面硅羟基与苄基氯反应,接枝量w(C)=6.68%;进一步磺化,接枝率w(S)=8.46%。XRD等分析结果表明,经过两步接枝反应,SBM仍然具有介孔结构特征,比表面积和孔容分别为366.9 m2/g、0.349 cm3/g。以SBM为催化剂,催化合成柠檬酸三丁酯;在n(酸)∶n(醇)=1.0∶9.0,w(催化剂)=3%,反应温度110℃,回流时间7 h的条件下,柠檬酸转化率可达93.2%;催化剂重复使用4次柠檬酸转化率为76.3%。     

间溴苯氧丙酸与7-溴苯并二氢吡喃-4-酮的合成

以间溴苯酚和3-溴丙酸为原料,合成了间溴苯氧丙酸,并以间溴苯氧丙酸为原料,进一步合成了7-溴苯并二氢吡喃-4-酮。探讨了投料比、反应时间、反应温度、氢氧化钠的质量分数和加料顺序等因素对间溴苯氧丙酸收率的影响。适宜的反应条件为:n(间溴苯酚)∶n(氢氧化钠)∶n(3-溴丙酸)=1∶1∶1.3,反应温度95℃,氢氧化钠的质量分数8%,反应时间7 h,间溴苯氧丙酸收率71.4%。以间溴苯氧丙酸为原料,以85%的收率合成了7-溴苯并二氢唑喃-4-酮。     

癸酸癸醇酯的合成

以氯化亚锡为催化剂,采用癸酸和癸醇为原料合成癸酸癸醇酯,考察了催化剂用量、反应温度、酸醇配比及反应时间对酯化反应的影响。当催化剂用量为总物料重量的0.05%,反应温度为180～190℃,酸醇配比n(癸酸)∶n(癸醇)=1∶1.15,反应时间为6.0 h时,癸酸的酯化率达到99.7%。     

二水湿法磷酸工艺磷收率提升的研究与应用技术

针对全球磷资源贫化、磷酸装置磷收率偏低的状况,重点研究影响磷收率的关键因素和介绍提升磷收率的若干技术,应用于生产取得磷收率、洗涤率、磷矿分解率分别达约97%、99%、98%,磷石膏中w(P2O5枸溶)由原0.5%降至0.14%,w(P2O5水溶)降至0.16%的较好效果。     

盐酸法饲料磷酸氢钙工艺中酸解渣过滤强化的研究

针对国外某磷矿为原料的盐酸法饲料磷酸氢钙工艺,通过分析酸解渣的粒度分布、物相及zeta电位等物理性质,研究了磷矿酸解渣过滤困难的原因,探索了强化过滤的途径。研究结果表明：在盐酸中加入少量硫酸,可显著提高酸解渣的过滤强度,最适宜的硫酸用量为混酸中W（H2SO4）0．67％。另外,加入适量的滤液于酸解液中,能降低酸解液中酸解渣颗粒之间排斥力,可显著提高酸解渣的絮凝效果及沉降速度。     

预转化预吸收高浓度SO2烟气制酸工艺的工业应用

介绍了金隆铜业高浓度SO2烟气预转化预吸收工艺原理和工艺流程。将SO2风机出口一部分φ（SO2）〉14%干燥烟气抽入预转化预吸收系统,加入部分预吸收后烟气及干燥空气以调节混合烟气SO2浓度和氧硫比,使进预转化器烟气φ（SO2）约12%。另一部分预吸收后烟气返回主转化系统与主烟气混合,进行常规的二转二吸工艺制酸。该工艺具...     

带HRS预转化工艺在烟气脱硫中的应用

介绍了高硫煤脱硫和制酸工艺的选择。高硫煤燃烧烟气采用有机胺法脱硫,解吸出的高浓度SO_2气体果用带HRS的预转化单吸制酸工艺加以处理。通过孟莫克预转化工艺、一转一吸工艺、带蒸汽喷射HRS工艺三位一体优化组合,使得制酸装置副产蒸汽量最大化、投资最小化进转化工序气体φ（SO_2）20.0%～22.0%较佳,HRS系统的吨酸...