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61.
Controlled environment experiments were set up in 2007 and 2008 to evaluate the potential of using by-products of the biofuel industry as soil amendments to improve fertility and plant growth in Saskatchewan soils. Trials were run with thin stillage (a by-product of ethanol production) and glycerol (by-product of biodiesel production). Canola (B. napus L.) and wheat (T. aestivum) were grown as the test crop in amended pots. Plant yield, composition, and soil properties were measured after five weeks. The stillage was found to be an effective soil amendment for increasing plant biomass yield. Per unit of nitrogen (N) added, canola yields were less than that of urea when nitrogen was the only limitation, due to only a portion of the nitrogen in the thin stillage becoming available over the five week period. However, when nutrients other than nitrogen were limiting, canola dry matter yields with thin stillage amendment approached or exceeded that of urea, due to the ability of the amendments to supply other nutrients such as phosphorus in addition to nitrogen. Glycerol, an amendment that only contains carbon, hydrogen and oxygen, was effective in increasing soil organic carbon content, but required supplemental fertilizer to account for nutrient tie-up by microorganisms during decomposition in the soil. The amendments did not have any biologically significant effects on other soil chemical parameters measured, including soluble metals, pH or salinity. 相似文献
62.
以丙三醇和2%质量分数硼酸的复配物为防腐剂,以脲醛树脂胶为胶黏剂,采用响应面分析法对室内用马尾松防腐胶合板的制作工艺进行优化,并用傅立叶变换红外光谱(FTIR)进行表征分析.结果表明,马尾松防腐胶合板的最佳制作工艺为:防腐液中丙三醇的质量分数1.91%,干燥温度75℃,干燥时间4h.在此条件下制作的马尾松防腐胶合板胶合强度为1.39MPa,与理论预测值基本一致.FTIR分析表明硼酸与丙三醇混合后反应生成硼酸酯,硼酸酯对木材结构和胶粘剂的固化不会造成不良影响,因此制作的马尾松防腐胶合板胶合强度可以达到国家标准GB/T9846-2004中Ⅱ类胶合板的要求. 相似文献
63.
为筛选一种较好的酶标抗体稀释液,试验以磷酸盐缓冲液(PBST)为基础溶液,通过添加甘油、酪蛋白、海藻糖及防腐剂Proclin 300等试剂配制了4种不同组合的酶标抗体稀释液,分别在4℃和37℃条件下考察其对酶标抗体稳定性的影响。结果表明,处理5(0.01 mol/L PBST+3%酶稳定剂M+3%海藻糖+0.05%Proclin 300)的保护效果最好,在4℃保存6个月,酶标抗体的活性仅降低18%。 相似文献
64.
两种方法保存嗜酸乳杆菌效果的比较研究 总被引:1,自引:0,他引:1
在相同的温度和时间条件下,比较滤纸片法和甘油生理盐水冻存法保存嗜酸乳杆菌的效果。用滤纸片法和甘油生理盐水冻存法,分别进行不同温度的嗜酸乳杆菌保存试验;并于预定时间内,对各处理组分别进行复苏及预定检测。在室温和4℃条件下,用滤纸片法保存的嗜酸乳杆菌出现了生化特性和形态的异常状况。随着保存时间的延长,滤纸片保存法比甘油生理盐水冻存法的嗜酸乳杆菌存活量明显减少。两种方法保存的菌种,均表现为-80℃组的嗜酸乳杆菌存活量明显大于-20℃组。说明在-80℃温度条件下,甘油生理盐水冻存法比滤纸片法具有较大的嗜酸乳杆菌存活量。 相似文献
65.
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67.
Influence of partial or total replacement of glycerol by alternative cryoprotectants in Ghent freezing extender on post‐thaw sperm quality in stallions 下载免费PDF全文
Although glycerol is the cryoprotectant most commonly used in stallions, it has also a considerable toxicity for equine sperm. It was the aim of this study to analyse the quality of frozen‐thawed stallion semen after complete or partial replacement of glycerol in the freezing extender by alternative cryoprotectants. We hypothesized that partial or total replacement of glycerol by cryoprotectants occurring in cold‐resistant frog, insect or plant species results in similar or better semen quality after freezing–thawing. As basic medium, the commercial Ghent basic extender was used and either supplemented with glucose and urea, trehalose and proline, or trehalose and betaine. Based on a series of preliminary experiments, semen was frozen in either commercial Ghent cryopreservation extender (Ghent control), Ghent glucose–urea extender or a Ghent combined extender (glucose–urea, trehalose‐betaine and trehalose‐proline; volume ratio of 2:1:2) in a computer‐controlled rate freezer. After freezing–thawing, semen was analysed for motility, membrane integrity, phosphatidylserine translocation, mitochondrial membrane potential and chromatin condensation. No differences between Ghent control and Ghent glucose–urea extender were seen, while all endpoints except DNA integrity were negatively affected in Ghent combined extender (e.g., progressive motility: Ghent 49.2 ± 3.7, Ghent glucose–urea 46.5 ± 4.6, Ghent combined 24.4 ± 2.8%; p < .001). In conclusion, glycerol concentration in a commercial freezing extender for equine spermatozoa can be successfully reduced when urea as an additive cryoprotectant is added and the glucose concentration is elevated. However, total glycerol replacement with urea, betaine, proline and trehalose was less successful. 相似文献
68.
Antioxidative effect of BHA in soya bean lecithin‐based extender containing Glycerol or DMSO on freezing capacity of goat semen 下载免费PDF全文
M Rahmatzadeh H Kohram A Zare Shahneh A Seifi‐Jamadi E Ahmad 《Reproduction in domestic animals》2017,52(6):985-991
The aim of this study was to evaluate the effects of butylated hydroxyanisole (0 or 4 mM) along with different concentrations (5 or 7%) of glycerol (G) and dimethyl sulphoxide (DMSO) as cryoprotectant (CPAs) on freezability of goat semen. Semen was collected from four bucks (3–4 years) twice a week for five weeks. The pooled ejaculates were diluted with extender containing two different concentrations of G or DMSO in combination with BHA. Afterwards, the diluted samples were loaded into 0.25 ml straws and frozen using a standard protocol. After thawing motility parameters, viability, membrane integrity and total abnormality were assessed. The Results showed that the presence of BHA in extender, type and level of CPAs as main factors had significant effects on goat sperm viability, total and progressive motility after freezing–thawing processes (p < .05). Also, the interaction of BHA (0 and 4 mM) and levels of G or DMSO (5 or 7%) had a significant effects (p < .05) on total motility, viability and some characteristic. In this case, the addition of 5% G or DMSO with BHA resulted in highest motility and viability than the other groups (p < .05). The addition of G5 (with and without BHA) increased VSL and reduced abnormality than the other groups (p < .05). The results showed that the main effects of CPAs and CPAs level on membrane functionality were significant (p < .05). Also there were no significance differences in the interactive effects of MDA, VCL, VAP, ALH, LIN and STR among the groups (p > .05). Finally, it can be concluded that the use of 5% CPAs with or without BHA may result in better post‐thaw sperm quality of goat. 相似文献
69.
大豆生物解离纤维素是生物解离技术提取大豆油脂过程中产生的不溶性纤维素,合理利用该纤维素有利于生物解离技术推广。试验以大豆生物解离纤维素为基材,添加丙三醇后利用延流法制备可食性膜,测定不同丙三醇添加量下可食性膜拉伸强度、断裂伸长率、水蒸气透过率、玻璃化转变温度、颜色及亮度、水溶性。结果表明,丙三醇对可食性膜多种特性产生影响。丙三醇添加量增加,可食性膜断裂伸长率、水蒸气通过率、亮度及水溶性升高,拉伸强度及玻璃化转变温度降低。利用扫描电子显微镜观察可食性膜表面微观结构发现,添加丙三醇可提高可食性膜表面致密性与均一性;红外吸收光谱测定结果表明,丙三醇与大豆生物解离纤维素间产生氢键作用,在成膜过程中破坏纤维素分子间酯键,削弱纤维素分子间作用力。研究为大豆生物解离纤维素可食性膜的生产提供理论依据。 相似文献
70.
本研究旨在获得一株性能良好的2,3-丁二醇(2,3-BD)生产菌株。向酿酒酵母(Saccharomyces cerevisiae) W5/W141两株产2,3-BD菌株中添加不同浓度乙偶姻,并测定2,3-BD、乙醇和甘油产量随发酵时间的变化情况。S. cerevisiae W5最适乙偶姻添加浓度为12 g/L,且2,3-BD的产量在72 h达到最大,产量为2.54±0.03 g/L,甘油和乙醇转化率分别较未添加时下降了17.6%和23.6%。S. cerevisiae W141最适乙偶姻添加浓度为10 g/L,且2,3-BD的产量在72 h达到最大,产量为1.71±0.02 g/L,甘油和乙醇转化率分别较未添加时下降了57.1%和16.7%。通过对比,本课题最终选用S. cerevisiae W5作为最适菌株,为微生物发酵法生产2,3-BD提供新的资源。 相似文献