排序方式： 共有18条查询结果，搜索用时 15 毫秒
1.
在用车尾气排放的治理和监管是中国城市大气环境改善的重点工作之一。利用典型在用车，对国家标准GB18285—2005规定的双怠速法、ASM法、VMAS法和IM195等在用车尾气排放检测方法进行了试验研究，探讨了ASM和VMAS两种检测方法的适用性。 相似文献
2.
羊驼毛纤维中黑色素含量的相关性研究 总被引：1，自引：1，他引：0
为研究羊驼毛纤维中黑色素含量的相关性,以为建立鉴定羊驼毛色的参数标准提供理论依据。选择肉眼观察认为表型不同的22种自然毛色的羊驼,每个表型选取3只羊驼,从背部采集羊驼毛,用不同的方法溶解,以乌贼黑为标准品,用紫外分光光度计法测定羊驼毛纤维中碱性可溶总黑色素(ASM)、真黑素(EM)和褐黑素(PM)的含量,通过单因素方差和线性回归曲线分别分析不同毛色羊驼毛纤维中黑色素的差异性和相关性。结果表明：ASM和EM在不同毛色的毛纤维中呈差异显著（分别为P＜0.01和P＜0.05）;而PM呈差异不显著(P＞0.05)。线性回归曲线得到模式方程式：模式1：Sp.ASM＝-0.313+3.168×Sp.EM+E(R2：0.902,t=-3.732,P=0.000,E为误差项;模式2：Sp.EM＝0.285+0.143×Sp.ASM+E (R2：0.902,t=6.769,P=0.000,E为误差项。因此,羊驼ASM和EM与毛色具有很大的相关性,可以作为区别毛色的重要参数,二者间存在线性回归。 相似文献
3.
A 2-year study was conducted on the effects of irrigation and plant populations on yield of pickling cucumbers (Cucumis sativus L). The main plot treatments were no irrigation or irrigation at a frequency necessary to prevent the available soil moisture (ASM) from falling below 25 or 60%. The sub-plots consisted of 49 000 plants/ha (multi-harvest) or 123 000, 185 000 and 247 000 plants/ha (once-over harvest). Irrigation substantially increased the yield and improved the grades of both multi-harvest and once-over harvest pickling cucumbers. Highest yields were obtained from the multi-harvest operation with irrigation at 60% ASM level. Maximum yields were obtained with irrigation at 25% ASM level in the once-over harvest operation. All population densities of the once-over harvest operation produced similar yields when not irrigated. Increasing plant populations from 12 to 25 plants m?2 did not significantly affect yields under irrigated conditions. 相似文献
4.
The combination of plant growth-promoting rhizobacteria (PGPR) and plant resistance inducers is an alternative crop protection approach in modern agricultural systems. Despite the numerous reports regarding the improved suppression of plant pathogens by their combined application, little is known about the interactions among these components. In the present study, the persistence behavior of the plant activator acibenzolar-S-methyl (ASM) in the rhizosphere of tomato plants and its root uptake as well as systemic translocation ability in aboveground parts after combined use with certain Bacillus PGPR strains (B. amyloliquefaciens IN937a, B. pumilus SE34, B. subtilis FZB24 and GB03) were investigated. Additionally, the population dynamics of the PGPR strain B. subtilis GB03 at the tomato root system and rhizosphere soil applied with or without the pesticide were studied. The results showed that the addition of PGPR inocula did not affect the dissipation rate of ASM in rhizosphere soil. Also, the formation of its major metabolite CGA 210007 in soil was rapid, since it was detected one hour after root drench and it was maintained at high levels during the sampling period without considerable variations among the bacterial treatments compared to the control. The uptake and systemic translocation of ASM and its metabolite CGA 210007 from root to shoot was rapid and maximum concentrations were observed at 48–96 h after its application. It was revealed that in plants treated with the PGPR strains B. subtilis GB03 and B. pumilus SE34 the uptake and systemic translocation of ASM and CGA 210007 in the aerial parts of the tomato plants was significantly higher compared to the control receiving no bacterial treatment. Also, the populations of the strain B. subtilis GB03 showed high colonizing ability in the root system and the rhizosphere soil. PGPR strains that lead to enhanced pesticide uptake by plants should be further evaluated as components in integrated management systems. 相似文献
5.
《湖南农业大学学报(自然科学版)》2015,41(5)
为了改善城市污水混进垃圾渗滤液后经常出现的TN含量超标问题,运用数值模拟方法,基于活性污泥模型ASM2d构建推流式A2O工艺数学模型。经过灵敏度分析和参数校正后,模型出水中COD、TN含量、NH4+–N含量模拟值与实测值的相对误差分别为2.1%、2.6%和1.6%。采用单因素试验和多因素正交试验优化混合液回流比、污泥回流比、好氧段溶解氧对出水TN含量的影响,结果表明,当混合液回流比为400%,污泥回流比为100%,好氧段溶解氧控制在3 mg/L时可达到较佳脱氮效果。 相似文献
6.
María-Luz Herrero Brita Toppe Håvard Eikemo 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(7):666-671
Abstract In an attempt to find alternative products to classical fungicides, several products with low toxicity were tested against powdery mildew of roses. These products included resistance inducers (Bion, BABA, and ROS), potassium salts (Resistim, monopotassium phosphate), and seed extracts. The best results were obtained with acibenzolar-S-methyl (Bion). The utilization of Bion as prophylactic treatment, watered at a concentration 0.1–0.2 mg/ml, together with good cultural practices can be enough to effectively control powdery mildew on roses. Treatments with Resistim reduced the disease incidence, but not always significantly compared to the controls. None of the other products had effect on powdery mildew. 相似文献
7.
Climate change is expected to have substantial effects on agricultural productivity worldwide. However, these impacts will differ across commodities, locations and time periods. As a result, landowners will see changes in relative returns that are likely to induce modifications in production practices and land allocation. In addition, regional variations in impacts can alter relative competitiveness across countries and lead to adjustments in international trade patterns. Thus in climate change impact studies it is likely useful to account for worldwide productivity effects. In this study, we investigate the implications of considering rest of world climate impacts on projections of the US agricultural exports. We chose to focus on the US because it is one of the largest agricultural exporters. To conduct our analyses, we consider four alternative climate scenarios, both with and without rest of world climate change impacts. Our results show that considering/ignoring rest of world climate impacts causes significant changes in the US production and exports projections. Thus we feel climate change impact studies should account not only for climate impacts in the country of focus but also on productivity in the rest of the world in order to capture effects on commodity markets and trade potential. 相似文献
8.
王建康 《林业机械与木工设备》2009,37(12):43-46
介绍了将稳态工况法（ASM）检测技术应用于底盘测功机上,采用稳态加载、带负荷测试的方法,由分析仪器自动、定量、准确地检测出车辆排放污染物CO、HC和NOx的数值。通过对汽油车排放污染物、有害气体的净化、ASM稳态工况的检测原理、测试程序以及测试结果的分析研究,对测试不合格的电控汽油车采取有针对性的措施,以提高车辆检测的通过率。 相似文献
9.
Fabio Rossi Cavalcanti Mario Lucio Vilela Resende Joo Paulo Matos Santos Lima Joaquim Albenisio Gomes Silveira Jos Tadeu Abreu Oliveira 《Physiological and Molecular Plant Pathology》2006,68(4-6):198-208
The activities of antioxidant enzymes and photosynthetic responses were investigated in tomato (Lycopersicon esculentum L. var.) pre-treated by plant activators and inoculated by Xanthomonas vesicatoria. Plants were sprayed with acibenzolar-S-methyl, ASM [Bion® 50 WG (0.2 g l−1)] and aqueous extract from dry necrotic tissue flour (VLA) of ‘Lobeira’ (Solanum lycocarpum) bush. Four days later, the plants were challenged with a virulent strain of X. vesicatoria, under greenhouse conditions. Tomato leaves were then assessed to determine the activities of the main antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and ascorbate peroxidase (APX). A reduction of bacterial leaf spot severity was observed in plants treated by ASM (49.3%) and VLA (31.4%), without any in vitro inhibitory activity over the pathogen. Controls showed decreases in CO2 assimilation, transpiration, photosynthetic rates, and stomatal conductance. Water use efficiency and carboxylation efficiency were strongly affected in ASM- and VLA-treated, in comparison to controls and healthy plants. The tested substances induced increases in SOD and CAT activities in a delayed enzymatic response typical in compatible plant–pathogen interactions. Measured at daily intervals, activities of APX and POX were significantly (ρ0.05) higher in treated plants than in controls, except for APX in ASM-treated plants where no difference was found when compared to controls. Only POX was clearly induced at the earlier stages after spraying the tomato plants with ASM or VLA. Our results suggest that late increases in antioxidant enzyme activities may play a role in mitigating oxidative damage in restoring the photosynthetic imbalance imposed by the expansion of bacterial lesions. 相似文献
10.
M. C. Dufour C. Lambert J. Bouscaut J. M. Mérillon M. F. Corio‐Costet 《Plant pathology》2013,62(2):370-382