固体颗粒介质成形新工艺试验研究与应力分析

自行设计制造了固体颗粒介质传压性能试验与测试装置,通过试验测得到了固体颗粒的传压规律.建立了板料在拉深力作用下的两种力学模型:线性分布载荷和二次函数分布载荷的力学模型.自行设计制造了板料成形试验模具与装置,通过对成形试验件的测量与分析,建立了自由变形抛物线函数变形模型.对固体颗粒介质板料拉胀成形未贴模时塑性变形阶段进行了塑性变形分析,推导出了自由变形区的应力分布计算公式,为固体颗粒介质板料拉胀成形塑性理论研究奠定了基础.     

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.     

Pharmaceutical production of tableting granules in an ultra-small-scale high-shear granulator as a pre-formulation study

Objective: In some of drug developments, the amount of bulk drug powder to use in early stages is limited and it is not easy to supply a sufficient drug amount for conventional preparation methods. Therefore, an ultra-small-scale high-shear granulator (less than 5?g) (USG) was developed and applied to small-scale granulation as a pre-formulation.

Method: The sample powder consisted of 66.5% lactose, 28.5% microcrystalline cellulose and 5.0% hydroxypropylcellulose. The granules were obtained to agitate 5?g of the sample powder with 1.0?mL of water at 300?rpm for 5?min after pre-powder mixing for 3?min by the USG and the manual hand (HM) methods.

Results: The granules were evaluated by the 10% and 90% accumulated particle size and the recoveries of the granules and the powder solid. Median particle size for the USG and the HM methods was 159.2?±?2.3 and 270.9?±?14.9 µm, respectively. The USG method had a narrower particle size distribution than those by the HM method. The recovery of the granules by USG was significantly larger than that by the HM method.

Conclusion: Characteristics of all of the granules indicated that the USG method could produce higher quality granules within a shorter time than the HM methods.     

Improved performance of a tubular microbial fuel cell with a composite anode of graphite fiber brush and graphite granules

In this study, a composite electrode combined of a graphite fiber brush and carbon granules (MFC-GFB/GG) was adopted as the anode of a tubular microbial fuel cell (MFC). Compared with an MFC with graphite granules (MFC-GG) and an MFC with a graphite fiber brush (MFC-GFB), MFC-GFB/GG showed a longer lag time during the start-up process, while it reached the highest operating voltage at 50 Ω. Furthermore, during the stable operation, the MFC-GFB/GG achieved the highest power density of 66.9 ± 1.6 W m⁻³, which was about 5.3 and 1.2 times as that of MFC-GG and MFC-GFB, respectively. The highest performance of the MFC-GFB/GG can be attributed to the highest active biomass content on the electrode and the smallest internal resistance of the MFC. The optimum COD concentration was found to be 500 mg COD L⁻¹ for MFC-GFB/GG.     

Influence of pH and ionic strength on Cu(II) biosorption by aerobic granular sludge and biosorption mechanism

BACKGROUND: To elucidate the process and mechanism of Cu(II) biosorption onto aerobic granules, the influence of pH and ionic strength (IS) on the Cu(II) biosorption capacity and biosorption mechanism was studied. RESULTS: The biosorption of Cu(II) onto aerobic granules under different conditions of pH (3, 4 and 5), IS (0, 0.1 and 0.5 mol L^?1) and Cu(II) concentration (25–250 mg L^?1) was investigated. The correlation coefficients of the pseudo‐second‐order kinetic model were , while those of the Langmuir and Freundlich models were and respectively. The biosorption of Cu(II) increased with increasing pH, while the effect of IS on the biosorption was complicated, which could be explained by the competition among different metallic ions, colloidal chemistry theory or Derjaguin, Landau, verwey and Overbeek (DLVO) theory. About 70% of the solid phase Cu(II) was exchanged by Na(I), Ca(II) and Mg(II) released from the aerobic granules at pH 4 and 5. The results revealed that ion exchange is the most important biosorption mechanism but that other mechanisms also play a part. CONCLUSION: The sorption performance can be optimised by adjusting the pH and IS. Aerobic granules can be used as an alternative effective, economical and practical biosorbent for heavy metal removal. Copyright © 2008 Society of Chemical Industry     

Modélisation de la cinétique de biodégradation de phénol par granules aérobies

This work describes a model of the biodegradation of phenol carried out by aerobic granules. These granules were obtained by culturing an activated sludge supernatant in a sequencing batch reactor fed with a synthetic waste water and subsequently, by acclimation to phenol (100 mg/L). The kinetics of phenol biodegradation by the aerobic granules was investigated over a wide range of initial phenol concentrations (40–1112 mg/L) in shake‐flask cultures. A Haldane‐type model was adjusted to the experimental results, which depicts successfully the phenol biodegradation profiles in the entire range of initial concentrations studied by using only one set of parameters. It is our view that the proposed model could contribute to the knowledge about the ability of aerobic granular systems to biodegrade toxic, inhibitory compounds such as phenol.     

10％毒死蜱颗粒剂的配方及加工工艺

[目的]通过试验筛选出10％毒死蜱颗粒剂的优惠配方和连续化加工工艺.[方法]以天然颗粒为载体,采用吸附法工艺,研究该制剂的配方组成、加工工艺和设备选型.[结果]试验产品质量稳定合格,流动性好,(54±2)℃、14d毒死蜱分解率≤5％,破碎率≤10％.[结论]在试验选定的配方条件下,所选的加工设备可以实现加工工艺连续化,各项技术指标符合颗粒剂的要求.     

新型灭螺剂的研究进展

血吸虫病在我国分布范围较广,严重威胁人们的身体健康,目前控制血吸虫病的有效方法就是杀灭钉螺。福寿螺作为一种外来入侵种,对水稻、蔬菜等农业生产造成了极大的损害。文章综述了我国目前采用的几种灭螺方法,介绍了利用化学药物和植物资源灭螺的研究机理和研究新进展,为灭螺剂的研究提供依据。     

真空干燥法制备甘薯全粉

选用真空干燥方法制备甘薯熟制全粉,研究了真空干燥温度、浸钙浓度、蒸制时间和乳化剂添加量对甘薯熟制全粉游离淀粉含量的影响。利用正交试验优化了工艺参数,当干燥温度为40℃,浸钙浓度为25 mg/L,乳化剂添加量为0.2%,蒸煮时间为12 min时生产出的甘薯熟制全粉品质最好,游离淀粉含量为21.89%。