改性木质素磺酸盐与黏结剂配伍的WG成粒性

[目的]改性术质素磺酸钠GCL4-1是一种优良农药分散剂,但其用于水分散粒剂(WG)时成粒性较国外产品稍差.[方法]将GCL4-1与6种农药常用黏结剂(淀粉、糊精、红糖、术糖、羟甲基纤维素钠、聚乙二醇)配伍后,测试WG的粒径分布及悬浮率、崩解性等性能.[结果]当淀粉质量分数为5％时,WG粒径在0.45～0.9 mm范围的颗粒达49.5％,热贮前后悬浮率分别为89.61％、87.77％,崩解液放置2h后沉淀层厚度为0.614 mm,稳定性略差于Kinsperse 126作分散剂制备的WG.糊精最佳质量分数为3％,此时粒径在0.45～0.9 mm范围的颗粒达45.6％,热贮前后悬浮率分别为91.26％、89.53％,崩解液放置2 h后沉淀层厚度仅为0.508 mm,稳定性与Kinsperse 126作分散剂的WG相当.[结论]淀粉和糊精与GCL4-1配伍使用能使WG具有较好的成粒性和优良的分散稳定性.     

Combining quantitative 2D and 3D image analysis in the serial block face SEM: application to secretory organelles of pancreatic islet cells

A combination of two‐dimensional (2D) and three‐dimensional (3D) analyses of tissue volume ultrastructure acquired by serial block face scanning electron microscopy can greatly shorten the time required to obtain quantitative information from big data sets that contain many billions of voxels. Thus, to analyse the number of organelles of a specific type, or the total volume enclosed by a population of organelles within a cell, it is possible to estimate the number density or volume fraction of that organelle using a stereological approach to analyse randomly selected 2D block face views through the cells, and to combine such estimates with precise measurement of 3D cell volumes by delineating the plasma membrane in successive block face images. The validity of such an approach can be easily tested since the entire 3D tissue volume is available in the serial block face scanning electron microscopy data set. We have applied this hybrid 3D/2D technique to determine the number of secretory granules in the endocrine α and β cells of mouse pancreatic islets of Langerhans, and have been able to estimate the total insulin content of a β cell.     

Granulation time in fluidized bed granulators

Size enlargement of particles in fluidized bed granulation involves mixing of particles with a binder liquid to form larger wet granules and drying them to form dry granules. Identification of the time for completion of granulation process is critical as further fluidization of dry granules is providing extra energy for their attrition. Monitoring the bed pressure drop and bed temperature of a batch fluidized bed granulator with time can provide information on the time for completion of the granulation process. Experimental observations on granulation time and size of granules in a lab-scale batch fluidized bed granulator are presented. Model based equations are developed for the estimation of granulation time and size of granules.     

MATHEMATICAL MODELLING AND APPARATUS ARRANGEMENTS OF DEEP DRYING PROCESS OF GRANULAR POLYMERS

ABSTRACT

A computer - aided analysis is made of the factors influencing the kinetics of the continuous deep drying of granular polymers on the basis of a two-level mathematical model. In terms of the lower (microkinetic) level, which deals with the drying of separate granules, consideration is given to the accuracy of determining the moisture diffusion coefficients in polymers as functions of temperature and concentration D=f(U,t). The expedience of employing the solution of linear and non-linear differential diffusion equations in microkinetic calculations is also considered. In terms of the macrokinetic level, which takes account of the influence of the hydrodynamic and heat-and-mass transfer drying conditions in the dryer, a numerical study is undertaken of how the kinetics is influenced by the granules’ dimension nonuniformity and by the difference in the granules’ residence time in the dryer. The results are graphically presented in generalised variables. The travel of 12 granular polymers in the shaft (column) dryers is experimentally studied depending on definite determining parameters. Accordingly, some recommendations aimed at ensuring the uniform drying are given. Presented are also the experimental results on the longitudinal mixing for different polymers for a continuous shaft dryer with a ring material layer and with the drying agent performing the radial motion. The findings make it possible to determine the mixing rate and to outline some practical recommendations. The investigations carried out allow one to find the rational construction of the dryer for the deep drying of granular polymers and to refine the kinetic calculations.     

高速公路滨海相软土工程特性初探

根据江苏连云港地区大量的工程地质勘察资料 ,就该区软土层的成因类型、物理力学特性、室内试验、现场原位测试 ,特别是力学指标的确定进行了深入的探讨和分析 ,结果表明 :室内试验确定的连云港地区软土力学指标误差大 ,有些指标与实际误差在二倍以上。用十字板、CPT试验方法有较好的效果     

示差折光高效液相色谱法测定复方胃蛋白酶颗粒中的糖

建立用示差折光高效液相色谱法测定复方胃蛋白酶颗粒中葡萄糖、蔗糖、麦芽糖含量的方法。选用色谱柱为Sugar-D,流动相为乙腈-水(78:22,V/V),流速为1.0mL/min,在室温条件下进样分析。结果表明：在该条件下,葡萄糖、蔗糖、麦芽糖能够较好分离,在 0.50～10.00mg/mL范围内线性关系良好;葡萄糖回收率为94.3%～103.7%,蔗糖回收率为101.4%～105.1%;经不确定度评价,合成不确定度为1.92%,扩展不确定度为4.1%。该方法简单、准确、稳定、可靠,可用于复方胃蛋白酶颗粒中葡萄糖、蔗糖的含量测定。     

A simple method to reduce the start-up period in a H2-producing UASB reactor

Introduction of an up-flow anaerobic sludge blanket (UASB) reactor apparatus to fermentative hydrogen production (FHP) enormously improves H₂ production performance. However, the long start-up period required to form H₂-producing granules (HPG) remains as a major obstacle. In the present work, a completely-stirred tank reactor (CSTR) was operated for 7 days, and the mixed liquor in the CSTR was transferred to a UASB reactor (UASBr (I)) as a seeding source. Coffee drink manufacturing wastewater (CDMW) was used as a feedstock, constituting the first attempt to form HPG from actual industrial wastewater. The strategy employed here was found to be more effective in developing HPG than directly starting from the UASB reactor (UASBr (II)), which is attributed to substantially higher active mass transfer in the CSTR. The average size of particles in the UASBr (II) blanket zone after 50 days of operation corresponded with that in the CSTR after only 7 days of operation. The drastic decrease of extracellular polymeric substance (EPS) protein concentration in the CSTR operation also indicates efficient removal of non-active biomass, the presence of which could adversely affect HPG formation. UASBr (I) showed a stable H₂ yield and H₂ production rate of 1.78 mol H₂/mol hexose_added and 2.76 L H₂/L/h, respectively, and HPG with an average size of 1.9 mm were developed after 45 days. It appears that the abundant presence of divalent ions, especially calcium ions, contained in the CDMW facilitated HPG formation.     

响应面法优化顶空固相微萃取分析茉莉加香颗粒挥发性成分

为准确分析茉莉加香颗粒挥发性成分组成特征,采用顶空固相微气相色谱质谱联用技术,以总峰个数为指标,采用单因素实验法分析萃取温度、萃取时间、解吸时间对萃取效果的影响,然后在此基础上运用Box-Benhnken 中心组合试验设计响应面优化萃取条件,并在最优萃取条件下对茉莉加香颗粒挥发性成分进行分析鉴定。结果表明:(1)顶空固相微萃取茉莉加香颗粒挥发性成分的最佳条件为:纤维萃取头50/30μmDVB/CAR/PDMS,萃取温度62℃,萃取时间26.5 min,解吸时间2.6 min。(2)在最佳条件下茉莉加香颗粒共检测出61种挥发性成分,占流出组分总量的87.97%,其中酯类16种,烯烃类21种,烷烃类7种,醛酮类3种,酚类1种,醇类2种,其他类11种,为茉莉加香颗粒挥发性成分的进一步研究提供了参考。     

青钱柳冲剂对糖尿病小鼠的降血糖功效

研究青钱柳冲剂对链佐霉素所致糖尿病小鼠的降血糖功效。以链佐霉素诱导小鼠糖尿病模型,设置模型对照组、正常对照组、阳性对照组以及青钱柳冲剂低、中、高剂量组,给药21d后,测定小鼠的空腹血糖、体质量、总胆固醇、甘油三酯、肝糖原等指标,并对小鼠胰腺组织的病理切片进行显微镜观察病变情况。结果表明：与模型对照组相比,青钱柳冲剂各组均能显著降低链佐霉素致糖尿病小鼠空腹血糖水平和总胆固醇量,显著增加体质量和肝糖原含量,并能减轻胰岛细胞病变程度。提示青钱柳冲剂对糖尿病模型小鼠具有明显治疗作用,其作用机理与其能调节肝脏糖代谢、恢复病变胰岛细胞的结构和功能有关。