共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
3.
4.
5.
在东北半干旱雨养条件下,以酱菜型菊芋品种榆林6号为供试材料,设置不覆盖(CK)、塑料薄膜覆盖(FM)和玉米秸秆覆盖(CS)3个处理,研究了地表覆盖措施对耕作层土壤水分状况及菊芋生长的影响。结果表明:塑料薄膜覆盖土壤的含水量是不覆盖土壤的1.7~2.0倍,玉米秸秆覆盖土壤的含水量是不覆盖土壤的1.3~2.0倍。与不覆盖处理相比,塑料薄膜覆盖和玉米秸秆覆盖均降低了土壤pH。覆盖措施显著影响了植株生长发育,至开花期玉米秸秆覆盖处理植株最高、茎最粗,株高平均达162cm、茎粗平均达18mm。塑料薄膜覆盖和玉米秸秆覆盖菊芋块茎平均产量为9 585和11 685kg·hm~(-2),分别增产63%和99%。因此,地表覆盖有利于土壤保墒,利于实现干旱地区菊芋的高产、高效栽培,值得推广应用。 相似文献
6.
以"青芋1号"菊芋为供试品种,对不同耕地类型菊芋种植模式进行了对比研究。结果表明,山旱地菊芋生长量仅为水浇地的1/2;宽窄行配置方式对生育前期菊芋茎、叶生长发育有一定促进作用,但未显示对块茎的增产效应;山旱地垄沟种植有利于促进茎、叶生长发育和块茎的膨大,增产效应显著。水浇地起垄种植有利于茎、叶生长发育和块茎的形成,增产效应显著。建议在山旱地适当提高种植密度以及采用垄沟种植,水浇地采用起垄种植。 相似文献
7.
在研制新型菊芋秸秆-烟煤混合固体燃料的基础上,筛选不同添加剂[MgCO3、CaCO_3、Al2O_3、Al_2Si_2O_5(OH)_5]优化燃料,以提高生物质混合固体燃料的燃烧性能。将四种添加剂以3%比例(质量比)与菊芋秸秆-烟煤混合固体燃料混合,比较了不同添加剂对混合固体燃料的灰分、结渣率、放热量、烟黑、灰熔点、烟气成分等的影响。结果表明:四种添加剂对酸性气体有明显的吸附作用,且能有效降低混合固体燃料的结渣率,其中CaCO_3添加剂使混合固体燃料的灰分含量、烟黑的林格曼指数下降最为明显。这表明,CaCO_3添加剂能有效缓解混合固体燃料中的灰分、烟黑、酸性气体的生成,提高其燃烧性能,是一种较为理想的新型菊芋秸秆-烟煤混合固体燃料添加剂。 相似文献
8.
9.
【目的】研究‘华红’苹果果肉在贮藏期间的流变特性(蠕变、松弛)变化规律,并进行流变特性参数间的相关性分析,用流变学方法预测评价果实质地品质,完善苹果果实品质评价体系。【方法】通过对‘华红’苹果果肉蠕变、松弛特性的研究,分别建立四元件Burger’s蠕变模型和三元件Maxwell应力松弛模型;分析蠕变、松弛参数随贮藏时间的变化规律,进行蠕变、松弛特性参数之间相关性分析,并利用SPSS软件进行蠕变、松弛特性主要参数的主成分分析。【结果】在‘华红’苹果贮藏过程中,蠕变特性参数初始弹性系数E1,延迟弹性系数E2,黏性系数η1、η2变化规律基本一致,均呈下降趋势,且这些参数间两两都呈极显著正相关;蠕变量呈缓慢上升趋势,与以上4个蠕变特性参数呈极显著负相关;延迟时间τ也呈缓慢上升趋势,达到最大硬度时做功呈先升高后降低的趋势,这两个蠕变特性参数和以上5个蠕变特性参数相关性较差;松弛特性参数零时弹性模量E0、平衡弹性模量Ee、衰变弹性模量E1、黏滞系数η、硬度、应力和总功变化规律基本一致,呈先下降略有升高后下降的变化趋势,且这7个松弛特性参数之间都呈极显著正相关。松弛时间T与其他7个松弛特性参数变化规律不一致,而且与它们相关性较差。运用主成分分析蠕变、松弛特性参数,第一主成分对10个变量指标的提取很充分,贡献率为88.828%。第一主成分‘流变因子’F1在贮藏过程中随着果实质地变软、食用品质的下降而呈下降趋势。【结论】‘华红’苹果果肉具有压缩黏弹性力学性质,四元件Burger’s模型和三元件Maxwell模型可以很好地拟合‘华红’苹果蠕变、松弛模型,可表征‘华红’苹果果肉贮藏期间流变力学特性变化规律,反应果肉质地变化状况。 相似文献
10.
11.
本文以斯里兰卡红茶为原料,采用气相色谱-质谱和高效液相色谱法研究以稀奶油为提取介质提取红茶香气物质的最佳工艺参数,并比较不同脂肪体系(稀奶油、脱脂奶、全脂奶、黄油、椰子油)与传统水提介质对红茶香气物质和滋味物质的影响,进一步分析在最佳工艺条件下中试生产的红茶冻干粉产品品质。结果显示:以稀奶油为提取介质提取红茶的最佳工艺参数为:脂肪含量3.8 wt%、料液比1:20、提取温度80℃,提取时间30 min。相较于传统水提技术,采用稀奶油和全脂奶为提取介质的乳提技术更有利于红茶中香气物质的提取,如斯里兰卡红茶特征冬青味的水杨酸甲酯的含量分别提高了1.51倍 和1.71倍。稀奶油提取的红茶中水溶性滋味成分含量与水提方式相近,而全脂奶和脱脂奶提取的红茶提取液中总单宁含量显著增加(P < 0.05)。不同动植物油脂来源的油脂体系影响红茶提取液香气物质含量。采用稀奶油提取红茶提取液中香气物质的含量要高于黄油和椰子油,均质乳化能显著提升三种油脂体系对红茶香气物质的提取得率。按照最佳的实验工艺参数进行中试生产,所得红茶提取物冻干粉品质存在差异,以稀奶油为提取介质的乳提红茶冻干粉香气物质含量显著高于水提红茶冻干粉。以上结果表明采用稀奶油为提取介质的乳提技术相较于传统水提能更有效的提高红茶产品的风味,同时中试生产证明乳提技术的工艺放大可行性。本实验结果可为制备具有独特风味和较高营养价值的含乳茶饮品提供实际生产指导。 相似文献
12.
黑穗醋栗属于皮部生根型。厚皮品种插条不定根的排列以簇生和纵生为主,薄皮品种以簇生和散生为主。解剖观察表明,黑穗醋栗具有先成不定根原基,起源于髓射线或次生射线与维管形成层交叉处。茎的结构及茎内营养物质含量均影响生根。生根期间全碳、全氮呈现规律性变化。厚皮品种硬枝各部位作插条,50 ppm NAA 或 IBA 处理1~5 min 生根较好,水培和土培方法均可采用;薄皮品种绿枝下部作插条,50 ppm NAA 处理1 min 或30 min 生根均较好,且以水培方法为宜。 相似文献
13.
从吉林,黑龙江两省5个地区采集的黑穗醋栗叶分析入手,比较了不同生态条件,峭同管理水平和不同产量水平叶片中元素含量。将53个叶片样本获得的分析数据归纳整理,并与国外文献分析比较、调整,分为缺乏、低值、适宜和高值范围,提出了适合我国东北地的穗醋栗叶分析标准,起来黑穗的合理施肥提供参考依据。 相似文献
14.
菊芋作为能源植物的研究进展 总被引:2,自引:0,他引:2
非粮能源植物是发展生物质能源的重要基础。菊芋适应性广,抗逆性强,生物质产量高,能源化利用方式多样,且环境友好,是我国有前景的非粮能源植物之一。笔者以原料生产和生物质转化利用为中心,对菊芋生物学、抗逆性和产量潜力、种质资源、遗传特性和良种选育、种植技术、化学组成和能源转化利用等方面的研究进展和存在问题进行了详细阐述,并展望了菊芋作为能源植物的研发前景。培育能源专用良种,建立适应能源生产的高效生产技术体系、获得高活力菊糖酶、高效发酵菌株和产油微生物,原料生产全生命周期评价及副产物综合开发利用是今后应着力研究的重点。 相似文献
15.
应用近红外光谱技术快速检测黑加仑浆果的主要营养成分 总被引:1,自引:1,他引:1
为了快速检测黑加仑浆果中的营养成分,用近红外光谱分析仪测量了黑加仑果浆样品近红外光谱(波长918~1 045 nm)吸收值,并用多元线性回归(MLR)、主成分回归分析(PCA)、偏最小二乘法(PLS)建立了同时测定黑加仑果浆中总酸、维生素C、总糖、花青素含量的数学模型,并对以上三种回归方法进行统计分析.结果表明,用多元... 相似文献
16.
1 Introduction Flavonoids are polyphenolic compounds occurring ubiquitously in plants and are commoncomponents in human diet.Over 40 0 0 differentflavonoids have been described and this list isstill growing.Flavonoids possess multiple biological effects such as antivirus,anticancino-gens,antidecrepitude and so on(Hollman,et al .1 996 .) .Besides,flavonoids have been em-phasized widely for the antioxidantactivities of inhibiting oxidation of lipid and gross food ef-fectively,pledging the s… 相似文献
17.
18.
Optimization of water and nitrogen management for surge-root irrigated apple trees in the Loess Plateau of China
下载免费PDF全文
![点击此处可从《农业科学学报》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The Loess Plateau is one of the main regions for growing apple trees in China, but a shortage of water resources and low utilization of nitrogen have restricted its agricultural development. A 2-year field experiment was conducted which included three levels of soil water content(SWC), 90–75%, 75–60%, and 60–45% of field capacity, and five levels of nitrogen application(N_(app)), 0.7, 0.6, 0.5, 0.4 and 0.3 kg/plant. The treatments were arranged in a strip-plot design with complete randomized blocks with three replications. For both years, the water and N_(app) had significant(P0.05) effects on leaf area index(LAI), yield, water use efficiency(WUE) and nitrogen partial factor productivity(NPFP) while the interaction effect of water and N_(app) on yield, WUE and NPFP was significant(P0.05) in 2018, and not in 2017. For the same SWC level, WUE first increased, then decreased as N_(app) increased, while NPFP tended to decrease, but the trend of LAI with different N_(app) was closely related to SWC. At the same N_(app), the LAI increased as SWC increased, while the WUE and NPFP first increased, then decreased, but the yield showed different trends as the SWC increased. The dualistic and quadric regression equations of water and N_(app) indicate that the yield, WUE and NPFP cannot reach the maximum at the same time. Considering the coupling effects of water and N_(app) on yield, WUE and NPFP in 2017 and 2018, the SWC level shall be controlled in 75–60% of field capacity and the N_(app) is 0.45 kg/plant, which can be as the suitable strategy of water and N_(app) management for the maximum comprehensive benefits of yield, WUE and NPFP for apple trees in the Loess Plateau and other regions with similar environments. 相似文献
19.
20.
The hydrolysis and photolysis of clomazone in aqueous solutions and natural water were assessed under natural and controlled conditions. Kinetics of hydrolysis and photolysis of clomazone were determined by HPLC-DAD. Photoproducts were identiifed by HPLC-MS. No noticeable hydrolysis occurred in aqueous buffer solutions ((25±2)°C, pH (4.5±0.1), pH (7.4±0.1), pH (9.0±0.1);(50±2)°C, pH (4.5±0.1), pH (7.4±0.1)) or in natural water up to 90 d. At pH (9.0±0.1) and (50±2)°C the half-life of clomazone was 50.2 d. Clomazone photodecomposition rate in aqueous solutions under UV radiation and natural sunlight followed ifrst-order kinetics. Degradation rates were faster under UV light (half-life of 51-59 min) compared to sunlight (half-life of 87-136 d). Under UV light, four major photoproducts were detected and tentatively identiifed according to HPLC-MS spectral information such as 2-chlorobenzamide, N-hydroxy-(2-benzyl)-2-methylpropan-amide, 2-[2-phenol]-4,4-dimethyl-3-isoxazolidinone and 2-[(4,6-dihydroxyl-2-chlorine phenol)]-4,4-dimethyl-3-isoxazolidinone. These results suggested that clomazone photodegradation proceeds via several reaction pathways:1) dehalogenation;2) substitution of chlorine group by hydroxyl;3) cleavage of the side chain. Photosensitizers, such as H2O2 and ribolfavin, could enhance photolysis of clomazone in natural sunlight. In summary, we found that photoreaction is an important dissipation pathway of clomazone in natural water systems. 相似文献