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991.
在果园的生产管理中,环境对果树的生长发育、栽培技术的实施、病虫害的预防等产生极其重要的影响。应用LabVIEW虚拟仪器开发平台,结合数据采集模块和各种传感器,实现了果园生态环境数据的实时采集,并利用LabVIEW自带的远程面板技术让客户远程监控服务器端。试验结果表明:系统能较好地实现果园生态环境远程实时监测,为果树生产管理提供决策依据。  相似文献   
992.
铝对大豆叶片水势和生理特性的影响   总被引:1,自引:0,他引:1  
以2个大豆{Glycine max(L.)Merrill}品种华春18,浙春3号为材料,设置不同的铝浓度进行土培试验,研究铝对大豆叶片水势和一些生理特性的影响。结果表明:高浓度的铝对大豆生长明显不利。随铝浓度的增加,大豆叶片水势略有下降;蛋白质含量在三叶期有所上升,然后在五叶期开始下降;叶绿素含量除三叶期外都有明显下降;二个大豆品种的SOD活性变化明显不相同。从种间差异性来看,浙春3号抗铝胁迫的能力大于华春18。  相似文献   
993.
采用盆栽玫瑰海棠的叶片作外植体进行组织培养试验。结果表明:用0.1%HgC l2对叶片表面灭菌10 m in的死亡率和感染率较低,接种于3/4 M S 6-BA 2.5 m g/L NAA 1.0 m g/L 琼脂7.8 g/L 蔗糖25g/L的培养基上诱导出新生芽,在3/4 M S 6-BA 1.0 m g/L NAA 0.2 m g/L 琼脂7.8 g/L 蔗糖25 g/L的培养基上,增殖系数可达6~8;在1/2M S KT 2.0 m g/L NAA 0.3 m g/L 琼脂7.8 g/L 蔗糖25 g/L的培养基上培养25 d左右,可形成6~9条粗壮的根和2.0~3.0 cm高的完整植株,试管小苗带培养基移栽到泥炭 泥沙 锯屑(1∶1∶1)的基质上,成活率达95%。  相似文献   
994.
电解功能水在养殖业的应用展望   总被引:2,自引:0,他引:2  
电解功能水是稀食盐水或稀盐酸溶液在电场作用下电解出的水溶液,根据电解程度不同可分为酸性电解水和碱性电解水。酸性电解水具有较强的杀菌能力,且杀菌广谱高效、安全、无化学物质残留;碱性电解水具有还原性,可作为活性饮用水。介绍了电解功能水的生成原理、杀菌机理和功能特性以及在养殖业的应用前景,以及对改善畜禽饲养环境、实现健康养殖的重要意义。  相似文献   
995.
Soil organic matter (SOM) is strongly related to soil type and management practices. Changes in government policy have brought drastic changes in farm management practices in the last two decades in rural China. This study investigates changes in SOM in two different soils: Ustepts and Udolls. Ustepts, in the North China Plain where the climate is warm and sub-humid, developed from an alluvial flood plain with organic matter <10 g kg−1. Udolls, in Northeastern China where the climate is cool and sub-humid, developed from loess-like materials with organic matter >20 g kg−1. Two locations for Ustepts and three locations for Udolls were used to collect 567 soil samples in 1980–1982 and again in 2000 for SOM analysis. Soil organic matter increased for Ustepts and decreased for Udolls soils over the sampling period, resulting from differences in fertilizer rates and crop residue input to soil. Higher fertilizer input and crop intensity and initially very low SOM content in Ustepts all contributed to greater OM input than oxidation release. In contrast, lower fertilizer input and crop intensity, and initially high SOM content in the Udolls, led to lower OM input than oxidation release. Increasing SOM content through higher mineral fertilizer input is a valuable option for sustainable agriculture production in areas where SOM is low and there is a shortage or potential shortage of food supply.  相似文献   
996.
Soybean proteins have shown great potential for applications as renewable and environmentally friendly adhesives. The objective of this work was to study physicochemical and adhesion properties of soy glycinin subunits. Soybean glycinin was extracted from soybean flour and then fractionated into acidic and basic subunits with an estimated purity of 90 and 85%, respectively. Amino acid composition of glycinin subunits was determined. The high hydrophobic amino acid content is a major contributor to the solubility behavior and water resistance of the basic subunits. Acidic subunits and glycinin had similar solubility profiles, showing more than 80% solubility at pH 2.0-4.0 or 6.5-12.0, whereas basic subunits had considerably lower solubility with the minimum at pH 4.5-8.0. Thermal analysis using a differential scanning calorimeter suggested that basic subunits form new oligomeric structures with higher thermal stability than glycinin but no highly ordered structures present in isolated acidic subunits. The wet strength of basic subunits was 160% more than that of acidic subunits prepared at their respective isoelectric points (pI) and cured at 130 degrees C. Both pH and the curing temperature significantly affected adhesive performance. High-adhesion water resistance was usually observed for adhesives from protein prepared at their pI values and cured at elevated temperatures. Basic subunits are responsible for the water resistance of glycinin and are a good starting material for the development of water-resistant adhesives.  相似文献   
997.
The amino acid composition and physicochemical and functional properties of hemp (Cannabis sativa L.) protein isolate (HPI) were evaluated and compared with those of soy protein isolate (SPI). Edestin, a kind of hexameric legumin, was the major protein component. HPI had similar or higher levels of essential amino acids (except lysine), in comparison to those amino acids of SPI. The essential amino acids in HPI (except lysine and sulfur-containing amino acids) are sufficient for the FAO/WHO suggested requirements for 2-5 year old children. The protein solubility (PS) of HPI was lower than that of SPI at pH less than 8.0 but similar at above pH 8.0. HPI contained much higher free sulfhydryl (SH) content than SPI. Differential scanning calorimetry analysis showed that HPI had only one endothermic peak with denaturation temperature (T(d)) of about 95.0 degrees C, attributed to the edestin component. The T(d) of the endotherm was nearly unaffected by 20-40 mM sodium dodecyl sulfate but significantly decreased by 20 mM dithiothreitol (P < 0.05). The emulsifying activity index, emulsion stability index, and water-holding capacity of HPI were much lower than those of SPI, and the fat adsorption capacity was similar. The data suggest that HPI can be used as a valuable source of nutrition for infants and children but has poor functional properties when compared with SPI. The poor functional properties of HPI have been largely attributed to the formation of covalent disulfide bonds between individual proteins and subsequent aggregation at neutral or acidic pH, due to its high free sulfhydryl content from sulfur-containing amino acids.  相似文献   
998.
空间变异在土壤性质长期定位观测及取样中的应用   总被引:14,自引:1,他引:14  
通过对中国科学院沈阳生态实验站30m×42m样地进行网格法分层取样,采用经典统计学与地统计学相结合的方法,以土壤pH和有机碳(TOC)为例,探讨了空间变异在土壤性质定位试验及取样中的应用。结果表明,49对样本的pH和TOC变异系数均小于10%,变量在0~10cm和10~20cm两个层次的基本统计数值基本接近,最佳理论模型的参数显示各变量空间变异主要受结构性因素的影响,且以135°方向的变异为主;相对误差为10%时采集6个和10个土样可分别达到95%和99%的置信水平,结合空间分布格局可以确定更为精确的取样方案;综合分析表明待选样地可以作为土壤性质长期定位观测试验用地。  相似文献   
999.
河漫滩上沉积物的沉积伴随着与沉积物相结合的营养和污染物质的沉积。已有研究表明,河漫滩是与沉积物相结合的磷的沉积地。采用137Cs技术,并结合河漫滩沉积物中全磷(TP)含量的剖面信息,可以调查近年河漫滩沉积物中的TP含量,计算TP储量。本文根据英国Devon郡Culm河8个河漫滩采样环沉积物中的数据,重建了在过去40~50年内TP储量和含量的变化。结果表明,在Culm河河漫滩沉积物中,在1963~2000年间TP平均含量为0.60~1.96gkg-1,该值自河流上游向下游和自过去到现在有逐渐增加的趋势;在相同的河漫滩沉积物中,在相同的时期内TP储量为18.62~435.48gm-2,即0.49~11.46gm-2a-1,最大值出现在河流的中游。  相似文献   
1000.
以土培和砂培黄瓜幼苗为试材,研究CO2施肥对植株矿质营养吸收和分配的影响。结果表明:每天上午以1100±100 μl/L CO2浓度施肥3 h或上、下午各施肥3 h明显降低植株各部位多数矿质元素的含量,CO2施肥时间延长,降幅增大。CO2施肥增强了黄瓜对矿质元素的吸收能力,使单株吸收总量显著增加,且施肥时间越长,吸收数量越多。因此,在CO2施肥的同时应增加矿质营养的供给。  相似文献   
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