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91.
以无核白葡萄干为原料,对无核白浓缩汁的生产工艺进行研究,确定最佳的工艺条件。结果表明,料液比1∶3,复水温度50℃,复水时间4 h为无核白葡萄干最佳复水条件;酶解最佳工艺条件酶解时间60 min,pH值3,酶解温度40℃;旋转蒸发最佳条件温度80℃,浓缩无核白汁可溶性固形物为40 Brix。 相似文献
92.
土壤矿物吸附和土壤团聚体对土壤有机碳含量的影响研究 总被引:2,自引:1,他引:2
Soil organic carbon (SOC) can act as a sink or source of atmospheric carbon dioxide; therefore, it is important to understand the amount and composition of SOC in terrestrial ecosystems, the spatial variation in SOC, and the underlying mechanisms that stabilize SOC. In this study, density fractionation and acid hydrolysis were used to assess the spatial variation in SOC, the heavy fraction of organic carbon (HFOC), and the resistant organic carbon (ROC) in soils of the southern Hulunbeier region, northeastern China, and to identify the major factors that contribute to this variation. The results showed that as the contents of clay and silt particles (0--50 μm) increased, both methylene blue (MB) adsorption by soil minerals and microaggregate contents increased in the 0--20 and 20--40 cm soil layers (P < 0.05). Although varying with vegetation types, SOC, HFOC, and ROC contents increased significantly with the content of clay and silt particles, MB adsorption by soil minerals, and microaggregate content (P < 0.05), suggesting that soil texture, the MB adsorption by soil minerals and microaggregate abundance might be important factors influencing the spatial heterogeneity of carbon contents in soils of the southern Hulunbeier region. 相似文献
93.
CCD radiation temperature measurement method for hot continuous casting billet surface 总被引:2,自引:0,他引:2
According to the present research status and existing problems of hot continuous billet surface temperature non contact measurement technology, a real time temperature measurement model, which combines two-color(R,G) and monochrome (B) of surface radiation image, is established. The surface image is collected through tricolor charge coupled device (CCD) sensor, at the same time, the temperature dynamic response range of CCD can be improved by controlling integrated time and setting different apertures. Through computer image process technology, multi-point temperature can be measured simultaneously, and 2-D temperature field distribution on continuous casting billet surface can be realized. It is be proved by theory and application that the model and method can provide a theory and technology support for realizing surface temperature field on-line measurement for continuous casting billet. 相似文献
94.
[Objectives]To probe into the treatment effects of soya lecithin powder combined with conventional therapy on chronic hepatitis B.[Methods]A total of 120 patien... 相似文献
95.
光纤光栅传感器具有抗电磁干扰、无需供电、耐腐蚀、灵敏度高等特点,已广泛应用于土木水利工程领域.引水隧洞作为水利行业一种常见的建筑结构,受隧洞本身结构、工程及环境等特点影响,其部分特殊洞段结构存在安全隐患,需对其进行长期有效的稳定性监测.以甘肃省引洮供水一期工程7号隧洞为例,介绍光纤传感技术在引水隧洞结构安全监测中的应用... 相似文献
96.
To overcome the shortage of existing experimental device for partial discharges in gas insulated switchgear(GIS),an installation for testing PD in GIS with multi-structures is designed, which can simulate T-type,L-type and line-type configurations of GIS expediently. The physical dimension and material parameter are given by calculating the characteristic of the propagation of ultra-high frequency electromagnetic waves and the stress of materials. The experiments under single defect and multiple insulation defects are carried on by using the designed 4 physical models of typical insulated defects for GIS. The results show that the built device can simulate the PD,TE mode and TM mode waves with different wave bands in GIS. The system makes a foundation for the further investigation of the electromagnetic waves propagation,the conditions of generating electromagnetic waves,testing method and pattern recognition of the PD in GIS. 相似文献
97.
98.
超微气泡增氧灌溉对水稻生育特性及产量的影响 总被引:3,自引:0,他引:3
以常规粳稻秀水09和杂交籼稻两优培九、国稻6号为试验材料,在2007和2008年采用大田试验,研究了超微气泡增氧灌溉对水稻生物学特性和产量的影响。结果表明,与常规灌溉相比,增氧灌溉处理具有分蘖发生快,叶面积指数大,干物质积累多等优点,尤其在生育后期表现出较大的干物质积累优势。增氧灌溉显著增加了水稻产量,其中秀水09分别增产8.45%(2007)和6.23%(2008)、国稻6号增产9.13%、两优培九增产7.49%。而且增氧灌溉明显提高了水稻有效穗数及结实率,但对水稻每穗总粒数和千粒重影响不明显。 相似文献
99.
Based on model parameters estimating, a kind of algorithm of pole-zero placement self-adaptive temperature control is put forward according to closed loop apices distribution of resistance furnace temperature control. The mathematic model is presented by discursion for the controlled object, at the same time, the algorithm is illustrated identification method of model parameters, compute formula and simulation result of controlled parameters. Simulations and practices of the model proved that the algorithm is of rapid constringency speed , satisfactory effect on the object with time changing especially for the controlled objects of the high current and low voltage characteristics. The algorithm has been applied in the temperature control of intelligent slag measurement equipment of a iron-steel graduate school. 相似文献
100.
植物病原菌诱导表达载体构建及在烟草中的瞬时表达研究 总被引:1,自引:0,他引:1
根据GenBank中植物病原物诱导型启动子碱基序列设计引物,以烟草基因组DNA为模板,扩增PPP3启动子。用PPP3替换pCAMBIA1301中与gus基因相连的35S启动子,构建重组质粒pCOMBIA +PPP3+gus后导入农杆菌GV3101。通过农杆菌介导的瞬时表达技术将受PPPs控制的gus基因导入烟草。分别接种青枯菌和水杨酸24 h后,烟草叶片中检测到gus基因转录效率分别提高了27.94,17.69倍。表明PPP3启动子具有本底表达水平低、诱导表达活性强的特点。 相似文献