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1.
以高油花生宇花9号和宇花14号为研究对象,以普通花生海花1号和亲本花育20号作为对照,采用溶剂浸提法提取花生油,对花生油的感官品质、理化品质、脂肪酸组成及相对含量进行研究,并通过相关性分析和主成分分析探究花生油脂肪酸组成的关系。结果表明:试验制得的花生油均为黄色、澄清透明的液体,具有花生油固有的滋味和气味。宇花9号和宇花14号花生油酸价、碘值均显著低于亲本花育20号,酸价分别为0.08 mg/g和0.27 mg/g,碘值分别为94.20 g/100 g和93.08 g/100 g。脂肪酸检测结果表明:宇花9号、宇花14号油酸含量高,分别为42.510%和41.976%,油亚比分析结果表明宇花9号、宇花14号更耐贮藏。主成分分析和相关性分析表明,花生油主要脂肪酸为棕榈酸(C16:0)、硬脂酸(C18:0)、亚麻酸(C18:3n3)、花生酸(C20:0)、花生一烯酸(C20:1),单不饱和脂肪酸与多不饱和脂肪酸存在极显著负相关,且与饱和脂肪酸存在极显著正相关,多不饱和脂肪酸与饱和脂肪酸存在极显著负相关。综合以上分析,相对比海花1号和花育20号,推测宇花9号和宇花14号更耐储藏。  相似文献   
2.
采用第一原理赝势平面波方法研究迹量元素N在γ-Ni/γ′-Ni3Al相界区域的占位趋势及其对相界断裂强度的影响。结果显示:以气态形式存在的N不易掺杂到Ni/Ni3Al相界,而以固态形式存在的N则很容易被掺进Ni/Ni3Al相界;N在Ni/Ni3Al相界中不仅能稳定存在,而且掺杂到八面体间隙比置换其中的基体原子具有更高的形成能力与结构稳定性;N掺杂将削弱Ni/Ni3Al相界的断裂强度,其中尤以间隙位掺杂最为明显。电子结构分析表明:置换型掺杂时,相界断裂强度的降低可归结为Frenkel缺陷导致的掺杂相界层间电子相互作用的减弱;而间隙位掺杂,除了基体原子间电子相互作用因掺杂原子与基体原子间的强相互作用而减弱外,晶格畸变导致的局域弹性应变能增加也是一个重要的原因。  相似文献   
3.
Changsha, a typical city in central China, was selected as the study area to assess the variations of ecosystem service value on the basis of land-use change. The analysis not only included the whole city but also the urban district where the landscape changed more rapidly in the center of the city. Two LANDSAT TM data sets in 1986 and 2000 and land use data of five urban districts from 1995 to 2005 were used to estimate the changes in the size of six land use categories. Meanwhile, previously published value coefficients were used to detect the changes in the value of ecosystem services delivered by each land category. The result shows that the total value of ecosystem services in Changsha declines from 1 009.28 million per year in 1986 to1 009.28 million per year in 1986 to 938.11 million per year in 2000. This decline is largely attributable to the increase of construction land, and the conversion from woodland and water body to cropland to keep the crop production. In the five districts, there is $6.19 million decline in ecosystem service value between 1995 and 2005. Yuelu District has the highest unit ecosystem service value while Yuhua District has the lowest one. This may be attributed to the greater conversion from cropland and grassland to woodland and water body with the increase of construction land in Yuelu District. It is suggested that the increase rate of construction land should be controlled rigorously and the area of woodland and water body should be increased or at least retained in the study area.  相似文献   
4.
The process of urbanization affects the urban warming. The change of urban warming was investigated by several urbanization factors in Changsha, China. The data of surface temperature (minimum, maximum and mean) of Changsha were analyzed to understand the possible effects of urbanization on the climate of this region owing to the population growth, built-up area expansion and energy consumption increases. The weights of these three factors were calculated by the analytical hierarchy process (AHP). Then, three weights were simulated with nonlinear method to obtain the urbanization development rate which was utilized to reveal the influence of the urbanization factors on the surface temperature. The result shows that there is a significant upward trend in the urban temperatures of Changsha. The temperature increase seems to be closely related to the rate of urbanization between 1993 and 2008, and there is an evidential increase trend of the influence on urban temperature by urbanization during 16 years. It is a quantifiable approach measuring the relationship between urbanization and urban eco-environment, and can be applied for the urban sustainability.  相似文献   
5.
钢铁企业节电节能措施及效果   总被引:1,自引:1,他引:0  
电力紧张和电价上涨,使钢铁企业面临更大挑战。介绍钢铁企业的用电状况,通过调整生产结构、需量控制技术,改善工序、优化电网结构、绿色照明等措施可以实现钢铁企业节电增效。  相似文献   
6.
Effects of added Cd on Cd uptake by oilseed rape and pai-tsai co-cropping   总被引:2,自引:0,他引:2  
The experiment was designed to study whether the decrease of Cd in the rhizosphere of Zhongyouza Ⅰ,one breed of oilseed rapes (Brassicajunica) that can hyperaccumulate cadmium from the soil, can improve the living condition of less Cd-tolerant plant pai-tsai (Brassia chinensis) with their roots permitted to intermingle and develop coincident rhizosphere. The extent of rhizosphere interactions between Zhongyouza Ⅰ and pai-tsai was controlled by different root barriers, or without barrier. The results show that in the 10 and 20 mg/kg Cd treated soils, pai-tsai gets higher shoot mass and less Cd accumulation in its shoot than in the barrier treatments or in the mono cultures, when its roots are permitted to intermingle with those of Zhongyouza Ⅰ. Meanwhile, soil decontamination rates of Zhongyouza Ⅰ are not affected much by co-cropping with pai-tsai, they are 80.0% and 91.8% of that in the mono cultures of Zhongyouza Ⅰ, respectively. However, the co-cropping method in meliorating the living condition of pai-tsai is not obvious when Cd concentration in soil reaches 40 mg/kg, and soil decontamination rate decreases to 0.14, which is 58.3% of that in the mono culture. These results indicate that the oilseed rape Zhongyouza Ⅰ may alleviate Cd toxicity of surrounding less-tolerant species, and its ability of phytoremediation is not affected much at the same time, especially in the middle polluted soil.  相似文献   
7.
几种面粉添加剂及其作用机理   总被引:4,自引:0,他引:4  
阐述了增白剂,品质改良剂(增筋剂,减筋剂,发酵剂),营养强化剂等食品添加剂的作用机理,并对增白剂和强筋剂作了安全性评价。  相似文献   
8.
湖南省矿山尾砂土壤污染现状分析   总被引:9,自引:0,他引:9  
对湖南省10个矿区的尾砂土壤进行了采样调查,分析了尾砂土壤的pH值、烧失量、阳离子交换容量、重金属含量以及重金属各种化学形态的含量。结果显示大部分土样中的Pb、Cd、Cu和Zn都超过了土壤中植物正常生长的最高容许浓度。各种重金属在土样中主要以残留态、硫化物和有机物结合态、或是Fe/Mn氧化物结合态存在,可交换态与碳酸盐结合态的含量极少。对各矿区尾砂土壤的污染指数(PI)与危险指数(DI)的计算表明,土样的PI与DI值分析显示1号永州铜矿、5号宝山铜铅锌矿、10号湘潭锰矿和7号冷水江铅锌矿需要尽快得到治理。  相似文献   
9.
本文介绍了糕点的加工工艺及其关键操作要点,探讨了糕点的膨胀机理,并对糕点中的气体来源进行了详细的阐述。  相似文献   
10.
1 Introduction Heavy metals like copper, mercury, chromium, cadmium, lead, nickel and zinc cause serious threat to environment, animals and human for their extreme toxicity[1]. Many industries including metal plating, mining, battery, pigment, dyestuff a…  相似文献   
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