莲籽壳仁分离与清选机械设计

目前,莲籽的加工是先切壳、穿芯,再进行分离与清选。由于壳与仁之间的间隙较小(0.1～0.2mm),莲籽穿芯、切壳后,多数壳、仁仍为一体,人工分离与清选难度加大,效率也很低下。为此,设计了莲籽壳仁分离与清选机械,将振动分离、揉搓分离、抛掷分离与气流分离有序结合,实施莲籽混合物中莲芯、碎壳和莲仁的分离与清选;介绍了莲籽壳仁分离与清选机械的主要结构和特点;分析了其工作原理和运动特性;确定了该机械的主要技术参数和经济指标。     

小球藻多糖的分离纯化和组成分析

采用冻结-融化方法,用冷水提取海水小球藻Chlorellasp.多糖,多糖经除蛋白、乙醇分级沉淀、柱层析等一系列步骤处理后,得到组分均一的小球藻多糖(简称CPSB-1)。将CPSB-1完全酸水解,用高效阴离子液相色谱对其溶液进行分析,结果表明:组成多糖CPSB-1的单糖有D-岩藻糖、D-鼠李糖、D-2-氨基葡萄糖、D-半乳糖、D-葡萄糖和几种未知的单糖;各已知糖基的摩尔比为D-岩藻糖∶D-鼠李糖∶D-2-氨基葡萄糖∶D-半乳糖∶D-葡萄糖=1.3∶1.0∶1.4∶1.2∶3.1。     

琯溪蜜柚砂囊粒化的无损检测

摘 要：柑橘砂囊粒化是柑果成熟期与采后贮藏期的常见生理性病害,严重影响果实品质。本文采用1.5 T 高场磁共振成像仪对采后贮藏30 d的琯溪蜜柚[Citrus grandis (L.) Osbeck]果实进行磁共振扫描检查,并以同层断面解剖图为对照,评估磁共振成像（MRI）应用于柑橘砂囊粒化症无损检测的有效性。结果表明, MRI检测中,T2WI能够显著区分果肉组织与海绵层组织的信号差异,其信号强度可代表果实组织相对含水量;T2WI信号在砂囊粒化部位强度显著降低,病变组织的失水特征清晰,与解剖结果一致。T2WI对砂囊粒化的确诊率100%,显著优于T1WI成像的识别率41.7%（χ2 = 5.76,P = 0.016）;T2WI和T1WI均能显示种籽照影,但T2WI对果肉组织影像的分辨率优于T1WI,因此MRI的T2WI分析可作为一种无损检测方法,对柚商品果实上市前砂囊粒化症发生程度以及种籽有无进行评估。     

水生栖热菌FL-03海藻糖合酶的分离纯化及特性研究

将从水生栖热菌FL-03中获得的海藻糖合酶粗酶液经硫酸铵分级沉淀、DEAE Sepharose CL-6B离子交换层析S、ephacryl S-200HR凝胶过滤层析后,纯化68.48倍,产率为18.4%。研究表明:该酶分子量约为101 kD,最适反应温度为60℃,最适pH为7.0,在40~80℃、pH 6.0~9.0范围内具有较高的反应活性和稳定性。Fe3 对该酶具有一定的激活作用,Cu2 、Tris、Zn2 对该酶具有较强的抑制作用。该酶具有高度的底物特异性,只能专一地将麦芽糖转化为海藻糖。在40℃4、8 h条件下,麦芽糖转化为海藻糖的转化率最大可达到79%。     

Screening of Feather Degrading Bacteria and Optimization of Fer-mentation Conditions from Poultry

The purpose of this experiment was to isolate and screen the microorganisms from the soil where chicken feathers were piled for a long time and identify them bi...     

Performance of a closed recirculating system with foam separation, nitrification and denitrification units for intensive culture of eel: towards zero emission

The development of a closed recirculating aquaculture system that does not discharge effluents would reduce a large amount of pollutant load on aquatic bodies. In this study, eel were reared in a closed recirculating system, which consisted of a rearing tank, a foam separation unit, a nitrification unit and a denitrification unit. The foam separation unit has an inhalation-type aerator and supplies air bubbles to the rearing water. The growth of eel, which were fed a commercial diet, was satisfactory, with gross weight increases of up three times in 3 months. The survival rate under the congested experimental conditions was 91%. The foam separation unit maintained oxygen saturation in the rearing water at about 80%. Furthermore, fine colloidal substances were absorbed on the stable foam formed from eel mucus and were removed from the rearing water by foam separation. Ammonia oxidation and the removal of suspended solids were accomplished rapidly and simultaneously in the nitrification unit. The ammonia concentration and turbidity were kept at less than 1.2 mg of N per litre and 2.5 units, respectively. When the denitrification process was operated, nitrate that accumulated in the rearing water (151 mg of N per litre) was reduced to 40 mg of N per litre. The sludge was easily recovered from the nitrification and denitrification tanks, and the components were found suitable as compost. Based on these results, the intensive aquaculture of freshwater fish such as eel can be achieved using a closed recirculating system without emission.     

Functional characterization of Farfantepenaeus californiensis, Litopenaeus vannamei and L. stylirostris haemocyte separated using density gradient centrifugation

Haemocytes from penaeid shrimp (Farfantepenaeus californiensis, Litopenaeus vannamei and L. stylirostris) were separated using a discontinuous Percoll gradient. Shrimp haemocytes were spontaneously adhered to glass, allowing slide preparations for staining and microscopic differential counting. Like other crustaceans, shrimp has three main populations differing in presence and size of cytoplasmic granules and each population seems to be biochemical or functionally compromised. Prophenoloxidase (proPO )activity was mainly located in large granules haemocytes (75%) while the small granules cells participate with 25%, but seem to be responsible for encapsulation. Haemocyte discrimination ability was tested using Sephadex? (Seph?), DEAE‐Seph? and CM‐Seph?. Only DEAE‐Seph? was encapsulated by shrimp haemocytes and provoked the release of proPO activating system, indicating the role of particle charge in the activation of shrimp immune response.     

割前摘脱联合收获机惯性沉降分离室能耗研究

4ZTL-1800割前摘脱稻(麦)联合收获机采用惯性沉降分离室来实现谷物与气流的分离。目前对惯性沉降分离室内气体的流动特性、压力损失特性及其受结构参数的影响规律等研究还未见研究报道。为此,建立了惯性沉降分离室内气相守恒方程,在此基础上应用Fluent软件对分离室结构参数对其压力损失的影响规律进行了数值模拟计算,得到了结构参数对压力损失的影响规律。经实验验证表明,模拟值与试验值基本吻合,研究结果为进一步优化惯性沉降分离室的结构、减小体积和降低压力损失提供了理论依据。     

棉种介电分选的试验研究

介电分选是一种新型的种子分选方法,具有结构简单、适应性强、分选效果好和可按种子活力进行分级的特点.电导率是反映种子活力的一个重要指标,分选电压是影响介电分选效果的一个重要因素,为了探讨电导率与分选电压之间的关系,介绍了棉种介电分选的原理,并在不同的分选电压条件下对棉种电导率进行了测定,同一条件下重复测定5次,所得数据用DPS统计软件进行分析处理.结果表明,分选电压对棉种电导率有影响,且回归效果显著.     

配体交换色谱手性流动相法拆分和定量茶氨酸对映体

建立了配体交换色谱手性流动相法拆分茶氨酸对映体的方法。采用Polaris C₁₈柱;流动相为L-脯氨酸：Cu²⁺（摩尔比）为2:1,Cu²⁺浓度为0.5βmmol/L,pH6.8,甲醇的加入体积比为2%;波长254βnm;流速0.9βml/min;柱温30℃。L-茶氨酸的进样量在0.09542βμg~4.241βμg范围内峰面积与进样量之间线性关系良好,回收率在97.45%~100.4%之间;D-茶氨酸的进样量在0.08486βμg~4.243βμg范围峰面积与进样量之间线性关系良好,回收率在97.07%~100.1%之间。该方法通用,准确。