不同入渗条件下土壤脱盐效果的试验研究

通过室内试验,采用控制土壤水流速和入渗水量的方法,研究了不同土壤水流速和入渗水量对土壤脱盐效果的影响。试验结果表明:入渗流速与入渗水量都是影响土壤脱盐效果的显著因素。入渗过程中,水分在土壤中的渗透流速越慢,脱盐效果越好;渗透水量和与之对应的单位水量排盐率呈极显著的幂函数递减关系。     

水杨酸对菊花花瓣生理和花期的影响

以不同浓度的水杨酸(SA)水溶液对菊花唐宇金秋全株进行喷雾处理,测定了整个花期花瓣中超氧化物歧化酶(SOD)活力、超氧阴离子(O2-)产生速率、可溶性蛋白和丙二醛(MDA)含量以及相对电导率的变化。结果表明:不同浓度的SA均能提高花瓣中SOD活力和可溶性蛋白含量,使O2-产生速率、MDA含量和相对电导率降低,花期有不同程度的延长,其中以10 mg/L处理效果较佳。     

宰后因素对肌肉保水性的影响

肉的保水性是肉的重要品质指标之一,与肌肉的其他品质指标如颜色、风味、嫩度等有着密切联系。综述了近年来冷却、电刺激等宰后因素对肌肉保水性影响的研究进展。     

Ce1-xDyxO2-δ固体电解质的合成及其性能研究

采用溶胶-凝胶法合成Ce1-xDyxO2-δ（x=0.05~0.50）固溶体,通过X射线衍射、拉曼光谱、原子力显微镜对样品进行结构表征,利用交流阻抗谱测试其电性能.结果表明：掺入Dy3＋可提高Ce1-xDyxO2-δ的电导率,其中Ce0.9Dy0.1O2-δ的电导率最高,活化能最小,600℃时的电导率为5.50×10-3S.cm-1,活化能为0.85 eV,比纯CeO2的电导率提高了3个数量级.     

镁离子对小鼠卵母细胞电激活效果的影响

为探索镁离子对卵母细胞激活的作用 ,研究了电激液、操作液和培养液中镁离子对小鼠卵母细胞电激活效果的影响。注射 h CG后 18h获取的小鼠卵母细胞 ,在含有或不含有 Mg2 的电激液、操作液和培养液中进行电刺激、洗涤和培养 ,并于培养 6 h和 9h后分别检查原核形成情况。结果发现 ,当用既含钙又含镁离子的甘露醇 (PM)进行电刺激 ,用含 Mg2 的 M2 (M2 )和 Whitten′s液 (WM)进行洗涤和培养时 ,卵母细胞激活率为 6 7.4 % ,而当电激液为不含 Mg2 甘露醇 (PM- )时 ,激活率降至 5 1.3% ,2组间差异显著 (P<0 .0 5 )。用 PM-电刺激 ,以 M2或不含有 Mg2 的 M2 (M2 - )洗涤并用 WM或不含有 Mg2 的 Whitten′s(WM- )培养 6 h,卵母细胞激活率分别为 5 0 .0 %、4 9.6 %和 5 3.8% ,3者间差异不显著 ,但显著 (P<0 .0 5 )低于用 PM、M2和 WM处理的对照组的激活率 (72 % )。培养 9h检查时 ,3个处理组的激活率均显著 (P<0 .0 5 )增加 (分别增加了 16 .7%、19.2 %和 18.2 % ) ,而对照组的激活率增加不明显 (5 % )。这些结果说明 ,电激液中的 Mg2 对卵母细胞的电激活率和原核形成速度有明显的促进作用 ,而操作液和培养液中的 Mg2 则对卵母细胞的激活率和原核形成速度没有显著影响     

应用电导法实时测定磷酸氢二铵和氯化钾混合肥液浓度

[目的]通过电导率(EC)准确反应水肥一体化条件下磷酸氢二铵和氯化钾不同配比值的肥液质量浓度.[方法]测定了一定质量浓度范围(2～10 g/L)和温度范围(20～45℃)内不同磷酸氢二铵和氯化钾配比混合肥液的EC值,并基于灰色关联分析(GRA)法研究了质量浓度ρf、温度T和配比值rv对磷酸氢二铵、氯化钾混合溶液电导率的...     

欧姆加热对米饭蒸煮过程能耗及其品质的影响

电饭煲蒸煮米饭存在电热转化效率低、温度不易控制等不足。该研究设计了一种加热速率和保温温度自动可控的欧姆加热试验系统,并研究了浸泡时间和水米比对水米混合物的电导率、欧姆蒸煮加热速率、能耗以及米饭品质（膨胀率、吸水率、物性值和颜色）的影响,并与电饭煲蒸煮米饭的能耗和品质进行比较。结果表明：浸泡能够增大水米混合物电导率,水米比越小电导率增加越快,有效提高欧姆加热蒸煮米饭加热速率;浸泡还有利于减少米饭蒸煮能耗（P<0.05）,促进米饭软化;因此大米浸泡处理30 min后采用欧姆加热蒸煮米饭可行。欧姆蒸煮加热速率越快,米饭硬度上升（P<0.05）,而黏性和弹性则略有减小（P<0.05）,加热速率在3～9 ℃/min范围内为宜;水米比可取1.25∶1～1.50∶1 mL/g。蒸煮相同质量的大米,欧姆加热所需能耗仅为电饭煲蒸煮的20%～25%;相较于电饭煲蒸煮,欧姆加热蒸煮米饭硬度最大可减小21%,且膨胀率和吸水率较大（P<0.05）、亮度L*值较小（P<0.05）。研究结果可为研发基于欧姆加热的快速高效米饭自动蒸煮装置提供技术支撑。     

Analysis on Dredger Fill Electrical Response Under Additive Electrical Field

With the purpose of the study on change rule of internal charge in soil specimens under differing circumstances, dredger fill, which was collected from Guangxi Beibu Gulf Economic Zone, was studied in various parameters, including the absence/presence of the applied DC electric field, different levels of field strength, soil water content, soil compactness, and degree of desalination. Moreover, through tentatively simulating the electrical response between thundercloud and earth mass, the triggered lightning mechanism of rock soil mass was explored. The results show that both additive electrical field and atmospheric electric field had influence over charge variation of soil, the impact of which would become more significant with the increasing field strength. Higher soil water content and lower degree of desalination could enhance the charge variation and conductivity of soil, whilst this action effect would remain stable when soil water content reached a certain degree. Although soil compactness make some effect for the charge distribution, its regularity is undefined so far.     

Effects of transportation during the hot season,breed and electrical stimulation on histochemical and meat quality characteristics of goat longissimus muscle

The effects of transportation and electrical stimulation (90 V) on physiological, histochemical and meat quality characteristics of two breeds of Omani goats were assessed. Twenty 1‐year‐old male goats from each breed (Batina and Dhofari) were divided into two groups: 3 h transported during the hot season (42°C day time temperature) and non‐transported. Animals were blood‐sampled before loading and prior to slaughter. Electrical stimulation was applied 20 min postmortem to 50% randomly selected carcasses of both breeds. Temperature and pH decline of the Longissimus was monitored. Ultimate pH, shear force, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss and colour were measured from samples of Longissimus dorsi muscles. Electrical stimulation and transportation had a significant effect on most biochemical and meat quality characteristics of Longissimus dorsi. The transported goats had higher plasma cortisol (P < 0.01), adrenaline, nor‐adrenaline and dopamine concentrations (P < 0.05) than non‐transported goats. Electrical stimulation resulted in a significantly (P < 0.05) more rapid muscle pH fall during the first 12 h after slaughter. Muscles from electrically‐stimulated carcasses had significantly (P < 0.05) longer sarcomeres, lower shear force value, a lighter colour (higher L* value), higher expressed juice and myofibrillar fragmentation index than those from non‐stimulated ones. Meat from transported goats had significantly higher pH, expressed juice and shear force, but contained significantly lower sarcomere length and L* values than non‐transported goats. The proportion of the myosin ATPase staining did not change as a function of stimulation, transportation or breed. These results indicated that subjecting goats to transportation for 3 h under high ambient temperatures can generate major physiological and muscle metabolism responses. Electrical stimulation improved quality characteristics of meat from both groups. This indicates that electrical stimulation may reduce detrimental effects of transportation on meat quality of Omani goats.     

五种冬季宿果植物抗寒性及电导率变化规律研究

对平枝栒子、小叶栒子、北美海棠、美洲南蛇藤、北海道黄杨5种冬季宿果植物于冬季进行电导率测定。结果表明:各参试树种在整个冬季的电导率呈现明显不同的变化趋势;春季与秋季电导率差值可反映出植物在冬季的受害情况;电导率波动反映出植物对低温受害的调节情况。北海道黄杨抗寒性较强,小叶栒子抗寒性差,平枝栒子、北美海棠、美洲南蛇藤抗寒性一般。