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1.
旨在满足马铃薯生产中茬口衔接、机械化生产技术应用、不利气候下稳产等对马铃薯出苗早、齐、壮的需求,以‘费乌瑞它’为供试品种,用基于有益活菌或工程菌提取物的5种生物制剂进行种薯处理,对多重性状进行了对比分析。5种生物制剂较常规化学制剂,均能够不同程度地促进种薯萌芽和芽根同生,出苗期提前2~7天,播种后49天的出苗率提高3.33%~17.78%。其中,表现最好的为酵母核苷酸衍生物和VDAL,种薯萌发和生根均显著高于对照。霜冻后,生物剂拌种处理在恢复前期促进植株生长,由此促进恢复后期的块茎发育,较常规化学处理增产8.39%~24.03%,体现了不同程度的保产效果。多马道黑、酵母核苷酸衍生物、根肽和VDAL体现出较好的保产效果,可作为种薯处理剂投入马铃薯生产。  相似文献   
2.
配料混合试验的设计和分析   总被引:2,自引:0,他引:2  
系统地介绍了配料混合试验的基本概念.指出了混合试验与常规因子试验的区别。提出配料混合试验的3种设计,即顶点和边界点设计、矩心设计和极顶设计。以2个实例演示了混合试验资料的统计方法,包括回归和方差分析.驻点分析和等值线分析。  相似文献   
3.
当前,我国农村普遍建立了居民最低生活保障制度,这是保障农村社会稳定的“最后一道安全网”,是中国农村社会保障体系的基础工程。但是,我国农村居民最低生活保障制度也还存在一些问题,例如保障对象、保障方式、保障资金、管理体制等,充分认识并采取 有效措施解决好这些问题,对于完善农村社会保障体系,维护农村社会稳定和经济发展有着重要现实意义。  相似文献   
4.
The population of male Kirtland's warbler (Dendroica kirtlandii) in the breeding season has averaged 206 from 1971 to 1987. The Kirtland's warbler occupies dense jack pine (Pinus banksiana) barrens from 5 to 23 years old and from 1.4 to 5.0 m high, formerly of wildfire origin. In 1984, 73% of the males censused were found in habitat naturally regenerated from wildfire or prescribed burning. The rest were in plantations (11%) or in harvested, unburned jack pine stands stocked by natural regeneration (16%). Twenty-two percent (630 of 2,886) of the Kirtland's warbler males counted in the annual censuses from 1971 through 1984 were found in 26 stands that were unburned and naturally regenerated following harvest. From 1982 to 1987, suitable regenerating areas were barely sufficient to replace currently occupied maturing stands, so population growth was impeded. Ecosystems of suitable size and regeneration characteristics (wildfire and plantation) doubled in area by 1989. In response, the population of Kirtland's warblers increased from 167 to 398 males between 1987 and 1992, but they withdrew almost entirely from the unburned, unplanted barrens by 1989 when the area of more suitable regeneration types increased. Minimum (368 males) and maximum (542 males) population estimates for 1996 were calculated based on 1984 average density (1.9 males per 40 ha) and peak population in burns (2.8 males per 40 ha).  相似文献   
5.
在关于混合态的海森堡不确定关系的基础上,研究了纯态和混合态的最小不确定性和压缩效应.虽然最小不确定态必定是纯态,但在某些并非最小不确定态的纯态或混合态中,依然可 以实现力学量不确定度的压缩.还给出了普通统计学的不确定关系,它们不涉及量子相干性却与量子力学的海森堡不确定关系具有相似的数学结构.  相似文献   
6.
The antibacterial potential of organic acids and essential oil components against Brachyspira hyodysenteriae, the causative pathogen of swine dysentery, was evaluated. Minimum inhibitory concentrations (MIC) of 15 compounds were determined at pH 7.2 and pH 6.0, using a broth microdilution assay. In addition, possible synergism was determined. MIC values for the three tested strains were similar. For organic acids, MIC values at pH 6.0 were lower than at pH 7.2. B. hyodysenteriae was most sensitive to cinnamaldehyde and lauric acid, with MIC values <1.5 mM. Most antibacterial effects of binary combinations were additive, however, for thymol and carvacrol, synergism could be observed. In vitro results demonstrate the antibacterial action of certain essential oil components and organic acids against B. hyodysenteriae.  相似文献   
7.
江彬  左停 《湖北农业科学》2016,(17):4612-4618
通过对湖南省新化县和陕西省柞水县的实地调查,探讨在农村最低生活保障制度与扶贫开发政策对接过程中出现的相关问题,探究其问题的原因及影响,从而提出相关建议。研究主要采用定量与定性相结合的方法,综合运用问卷调查、访谈法、参与式农村评估法、观察法等方法进行实地数据的收集。对两项政策的定位问题在功能方面、目标人群方面与信息方面进行梳理与探讨,分析其主要作用,剖析两项政策衔接的可行性、必要性及存在问题,从而为两项政策最终实现实质性对接提供借鉴。  相似文献   
8.
9.
ObjectiveTo determine the effect of remifentanil infusion on the minimum alveolar concentration of sevoflurane preventing movement (SEVOMACNM) and bispectral index (BIS) in dogs.Study designProspective, unmasked study.AnimalsA total of 10 adult Beagle dogs weighing 9.0 ± 1.1 kg.MethodsDogs were anesthetized with sevoflurane and baseline SEVOMACNM was determined. Remifentanil was infused at 5, 10 and 20 μg kg–1 hour–1, in sequence, with 20 minutes washout between infusions. Variables monitored throughout anesthesia included heart rate (HR), oscillometric blood pressure, end-tidal partial pressure of carbon dioxide, end-tidal sevoflurane concentration (Fe′Sevo) and BIS. SEVOMACNM after remifentanil infusion (SEVOMACNM-REMI) determination started 20 minutes after the start of each infusion. Venous blood samples were collected for plasma remifentanil concentration determination at baseline, SEVOMACNM-REMI determination time points, and 20 minutes after each infusion was stopped. A mixed model analysis was used to determine the effect of remifentanil infusion on response variables. The relationships between BIS and Fe′Sevo, plasma remifentanil concentrations and the percentage decrease in baseline SEVOMACNM were evaluated (p < 0.05).ResultsThe overall SEVOMACNM at baseline was 2.47 ± 0.11%. Addition of remifentanil at all infusion rates significantly decreased SEVOMACNM, but the medium and high doses resulted in significantly greater decreases in SEVOMACNM than the lower dose. There was no difference in SEVOMACNM percentage change between infusions 10 and 20 μg kg–1 hour–1. Plasma remifentanil concentrations were significantly different in all infusion rates. Baseline BIS value was 70 ± 1 and was lower than the BIS values recorded during all remifentanil infusions. BIS values were not significantly different among infusion rates. HR was lower and mean arterial pressure was higher during remifentanil infusions than at baseline.Conclusions and clinical relevanceAll remifentanil infusions decreased SEVOMACNM in dogs. Remifentanil infusion at any rate studied did not reduce BIS values.  相似文献   
10.
A minimum ring-band mathematical definition :In the done ring-band, there are at least two inner points and two outer points which scatter staggeringly on the circumference. With this definition as the rule of searching calculation' s ending,a fast numerical algorithm of gaining the minimum ring-band of a closed curve was suggested:Make a ring-band with the four points scattered staggeringly,then replace the old points with new ones continuously until all the points are located within the ring-band. The method was used in an application example to measure the spindle rotating precision of machine tools.  相似文献   
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