全豆豆浆与传统豆浆感官品质和营养成分对比

以大豆为原料,通过感官评定对胶体磨技术自制的全豆豆浆和一般机械磨加工的传统豆浆中的永和豆浆和普通豆浆的感官品质进行了比较,通过营养成分检测对全豆豆浆和永和豆浆的营养成分进行了比较,同时将检测的全豆豆浆营养成分与中国食物成分表中的普通豆浆的营养成分进行比较。结果表明:全豆豆浆口感浓厚,细腻爽滑,豆香味浓郁,无豆腥味,感官评价总得分高于传统豆浆中的永和豆浆和普通豆浆,差异有统计学意义(P0.01);全豆豆浆中蛋白质、脂肪、总膳食纤维、维生素B1、维生素B2、钙、磷脂及大豆异黄酮等营养成分含量均高于永和豆浆,更高于普通豆浆。全豆豆浆的普及不仅可以提高豆浆的营养价值,还可以减少资源的浪费,具有一定的社会和经济效益。     

草萘胺在五种土壤及其胶体上的吸附行为

土壤胶体是土壤中颗粒最细小的部分,由于具有巨大的比表面积和较高的吸附容量,是环境中污染物的重要吸附剂,直接影响到污染物的归趋和生物有效性.本文采用批次吸附试验的方法,研究了农药草萘胺在黄棕壤等5种土壤及土壤胶体上的吸附行为.结果表明,草萘胺在供试土壤及胶体上的吸附均能很好地符合Freundlich方程;与本体土壤相比,...     

Control of retention in paper-making by colloid titration and zeta potential techniques

The concentration influence of some commercial polyethylenimines, used as retention agents, on the retention efficiency during the sheet formation is studied in this paper. The conditions of an industrial wire end have been simulated by means of a dynamic jar of exclusive design. Measurements of the zeta potential have been taken to quantify the surface charge of particles and the colloid titration ratio (quotient between the cationic demand and the anionic demand of pulp slurries) has been evaluated. Both techniques have proved convenient to monitor the retention level; therefore, they are efficient methods to control the retention level in the sheet formation. The univocal relation existing between zeta potential and the logarithm of the colloid titration ratio has been demonstrated. Finally, the variation of the level of turbulence has proved the importance of the hydrodynamics factors in the retention.     

Efficiency of three boar sperm enrichment techniques

The objective of the study was to investigate the efficiency of three enrichment methods to separate boar spermatozoa. Twenty-four ejaculates from 12 boars (2 ejaculates/boar) were extended (30 × 10⁶ spermatozoa/mL) in commercial Beltsville Thawing Solution. Each semen sample was processed with glass wool column (GW) and glass beads (GB) filtration and with the single-layer centrifugation (SLC) technique. Semen samples before (control; C) and after treatment were evaluated for sperm CASA motility/kinetics and concentration, viability, morphology and chromatin integrity. Data were analysed with mixed models. The concentration of total and motile spermatozoa was significantly decreased after treatment in groups GW and SLC, but not in group GB. Group GW showed increased values of WOB compared with both groups C and GB. Group GB showed greater values of rapid movement spermatozoa and lower values of slow movement spermatozoa compared with group C. In group SLC, higher values of VSL, LIN and STR were observed compared with group C. In conclusion, all techniques under examination enhanced various CASA variables. Based on our results, the GB method is a promising alternative separation technique for boar sperm and deserves further research regarding swine in vitro fertilization.     

地下环境中胶体促使下的污染物运移研究进展

大量的研究证据表明,胶体能促使地下环境中污染物的运移。胶体的沉积、释放和运移等动力学过程受许多因素的控制,如胶体的表面性质(亲水或疏水)、胶体的稳定性、水溶液的化学组分、离子强度、pH值和水的流速等。许多研究者已提出了考虑不同影响因素的模型从理论上或用实验室土柱试验来模拟胶体的运移行为。在未来应加强野外条件下不同类型的天然介质中胶体促使下污染物运移的影响因素、作用机制和运移过程的研究,这有助于人们提出有效的策略或发展新的治理技术以防止污染的扩大或修复污染,最终达到保护地下环境的目的。     

低分子量有机酸对胶体矿物吸附酸性磷酸酶和牛血清白蛋白的影响 Ⅰ.乙酸的影响

研究了不同pH和乙酸浓度下 ,乙酸对酸性磷酸酶和牛血清白蛋白 (BSA)在土壤胶体、矿物表面吸附的影响。结果表明 ,在pH 2～ 8的乙酸体系中 ,酸性磷酸酶和BSA在胶体矿物表面的最大吸附pH值一般出现在蛋白的等电点和矿物的电荷零点 (PZC)之间。各土壤胶体和粘粒矿物对酶和BSA的吸附量大小顺序为 :针铁矿 黄棕壤 >砖红壤 >高岭石 >二氧化锰。乙酸浓度对蛋白分子在胶体矿物表面的吸附量和吸附结合能具有较显著影响 ,在 0～ 2 0 0mmolL- 1范围 ,随着乙酸浓度的增加 ,蛋白吸附量呈现出先升高 ,后降低 ,再稳定的趋势 ,而吸附结合能的变化与此相反。本文还就乙酸对酶和BSA吸附影响的可能机理进行了初步探讨。     

酒石酸对黏粒矿物上酸性磷酸酶吸附及活性的影响

采用平衡批处理法,研究了模拟根系分泌物——酒石酸溶液的浓度(0~80 mmol L-1)、pH(2.5~7.0)对酸性磷酸酶在针铁矿、高岭石及黄棕壤和砖红壤胶体(<2μm)上的吸附及比活性影响。结果表明,当酒石酸浓度由0 mmol L-1(作为对照)升高至80 mmol L-1时,酸性磷酸酶在供试土壤胶体和矿物表面的吸附量先急剧降低(0~5mmol L-1之间),后逐渐达到平衡;以羟基化表面为主的针铁矿对酸性磷酸酶的吸附百分率受酒石酸浓度的影响最大,吸附百分率从对照的96.2%降至80 mmolL-1酒石酸浓度时的33.7%,其他以层状铝硅酸盐矿物为主的供试土壤胶体和高岭石则受影响较小,吸附百分率从对照的76.3%~60.6%降至80 mmol L-1酒石酸浓度时的56.2%~41.6%。酸性磷酸酶在酒石酸体系中的最大吸附pH点均在该酶的等电点酸侧,这可能与酒石酸对矿物表面的电荷性质改变有关;酒石酸体系中,针铁矿上酸性磷酸酶的比活性远高于其它供试土壤胶体,该酶的最适比活性点随胶体类型的不同而无变化或有所高移。     

胶体存在时不同质地土壤对锌镉的吸附试验研究

以重金属离子Zn和Cd及胶体为对象,通过等温静态批量平衡吸附试验,分析了3种不同质地土壤对Zn、Cd单一吸附和等量竞争吸附特征,胶体对土壤吸附Zn、Cd的影响,并用Langmuir和Freundlich方程对试验结果进行了拟合。结果表明,随着平衡液中Zn2+、Cd2+浓度的增加,土壤对Zn、Cd的吸附量逐渐增大;3种质地土壤对Zn、Cd吸附量顺序为砂壤>粉壤>壤砂土;Zn2+、Cd2+共存时,土壤对这两种离子的吸附量比单一离子存在的情况下明显下降;胶体存在时抑制了土壤对Zn的吸附,促进了土壤对Cd的吸附;就本试验来说,Freundlich方程拟合效果优于Langmuir方程。