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991.
彭小兰  陈曙光  李丁 《安全》2010,31(11):9-11
文章先概述了RBI软件、RBI标准及RBI技术三方面在国内外的发展现状趋势及意义,然后从巴陵石化分公司煤制合成氨装置谈RBI的实施可行性、内容和关键技术,并预测了此项目实施带来的市场效益、经济效益和社会效益。  相似文献   
992.
993.
Aminomethylphosphonic acid (AMPA) is formed in glyphosate-treated glyphosate-resistant (GR) and glyphosate-sensitive (GS) soybean [Glycine max (L.) Merr.] plants and is known to cause yellowing in soybean. Although, AMPA is less phytotoxic than glyphosate, its mode of action is different from that of glyphosate and is still unknown. Greenhouse studies were conducted at Stoneville, MS to determine the effects of AMPA on plant growth, chlorophyll content, photosynthesis, nodulation, nitrogenase activity, nitrate reductase activity, and shoot nitrogen content in GR and GS soybeans. AMPA was applied to one- to two-trifoliolate leaf stage soybeans at 0.1 and 1.0 kg ha(-1), representing a scenario of 10% and 100% degradation of glyphosate (1.0 kg ae ha(-1) use rate) to AMPA, respectively. Overall, AMPA effects were more pronounced at 1.0 kg ha(-1) than at 0.1 kg ha(-1) rate. Visual plant injury (18-27%) was observed on young leaves within 3d after treatment (DAT) with AMPA at the higher rate regardless of soybean type. AMPA injury peaked to 46-49% at 14 DAT and decreased to 17-18% by 28 DAT, in both soybean types. AMPA reduced the chlorophyll content by 37%, 48%, 66%, and 23% in GR soybean, and 17%, 48%, 57%, and 22% in GS soybean at 3, 7, 14, and 28 DAT, respectively. AMPA reduced the photosynthesis rate by 65%, 85%, and 77% in GR soybean and 59%, 88%, and 69% in GS soybean at 3, 7, and 14 DAT, respectively, compared to non-treated plants. Similarly, AMPA reduced stomatal conductance to water vapor and transpiration rates at 3, 7, and 14 DAT compared to non-treated plants in both soybean types. Photosynthesis rate, stomatal conductance, and transpiration rate recovered to the levels of non-treated plants by 28 DAT. Plant height and shoot dry weight at 28 DAT; nodulation, nitrogenase activity at 10 DAT, and nitrate reductase activity at 3 and 14 DAT were unaffected by AMPA. AMPA reduced root respiration and shoot nitrogen content at 10 DAT. These results suggest that a foliar application of AMPA could indirectly reduce photosynthesis through decreased chlorophyll content in GR and GS soybean up to 14 DAT, but affected plants can recover to normal growth by 28 DAT.  相似文献   
994.
西安市冬、夏两季PM2.5中碳气溶胶的污染特征分析   总被引:5,自引:0,他引:5  
为研究西安市冬、夏两季大气颗粒物PM2.5中碳组分的污染变化规律,利用TEOM系列RP1400a采样仪于2010年冬季和夏季进行采样,测定了样品中的有机碳(OC)、无机碳(EC)和水溶性有机碳(WSOA)的含量。结果显示,PM2.5中OC和EC的季节平均浓度值冬季较高,分别是夏季的2.62,1.75倍,这表明西安市冬季碳气溶胶污染严重。OC和EC日变化在不同季节均呈现双峰分布特征,这主要是由交通源的排放和不利的气象条件造成的。OC和EC在冬、夏两季都有较强的相关性(R2分别为0.823和0.543),且OC/EC平均值分别为5.36和3.58,均大于2,表明采样各时段有二次有机碳(SOC)生成。  相似文献   
995.
Information on the vertical distribution of air pollution is important for understanding its sources and processes and validating satellite retrievals and chemical transport models. This paper reports the results of the measurements of sulfur dioxide (SO2) and aerosol scattering coefficient (Bsp) obtained from several aircraft campaigns during summer and autumn 2007 in the north-eastern (NE), north-western (NW), and central-eastern (CE) regions of China. Their vertical profiles over the three regions with contrasting emission characteristics and climates are compared. Very high concentrations/values of SO2 and Bsp (with a value of up to 51 ppbv and 950 Mm?1, respectively) were recorded in the lower planetary boundary layer in CE China, indicating high SO2 emissions in the region. The SO2 column concentrations determined from the in-situ measurements were compared with Ozone Monitoring Instrument (OMI) SO2 retrievals. The results show that the OMI data could distinguish the varying levels of SO2 pollution in the study regions, but appeared to have underestimated the SO2 column in the highly polluted region of CE China.  相似文献   
996.

Purpose

This study evaluates manure and chemical fertilizer effects on micronutrient (Fe, Mn, Cu, and Zn) content and availability in crops.

Methods

Seven treatments were selected, including three conventional fertilization treatments (NP, horse manure (M), and NP plus M (NPM)), three corresponding double rate fertilization (N2P2, M2, and N2P2M2), and a CK. Soil samples were collected and separated into four aggregates by wet-sieving in September 2009. Corn samples were collected and analyzed simultaneously.

Results

Treatment N2P2 increased DTPA extractable Fe, Mn, and Cu in soil by 732%, 388%, and 42%, whereas M2 decreased the corresponding values by 26%, 22%, and 10%, respectively, compared to CK. DTPA extractable Zn in soil and Zn in corn grain were higher in the M and M2 treatments than in the other treatments, and DTPA Zn was significantly correlated with soil organic carbon (SOC) in large macroaggregate, microaggregate, and silt + clay fractions. The Mn concentrations in corn stalks and grain were significantly correlated with DTPA extractable Mn in bulk soil and microaggregates, and Zn in stalks were significantly correlated with DTPA Zn in bulk soil, microaggregates, and large macroaggregates.

Conclusions

Long-term application of horse manure could increase soil Zn availability and uptake by corn, possibly due to its activation by SOC. In contrast, chemical fertilizer application increased DTPA extractable Fe, Mn, and Cu in soil by reducing soil pH. Our results also suggest that Mn uptake by corn originated mainly in microaggregates, whereas Zn in crops was primarily sourced from large macroaggregates and microaggregates.  相似文献   
997.
MicroRNA (miRNA) plays a crucial role in gene expression regulation. However, no data are available on change of miRNA expression of zebrafish (Danio rerio) after treatment with pesticides. We evaluated the effect of fipronil (5-amino-1-[2, 6-dichloro-4-(trifluoromethyl) phenyl]-4-[(trifluoromethyl) sulfinyl]-1H-pyrazole-3-carbonitrile) and triazophos (3-(O, O-diethyl)-1-phenyl thiophosphoryl-1, 2, 4-triazol) and their mixture on miRNA expression in zebrafish. MiRNA expression profiles in zebrafish were altered after treatment with these chemicals. An association between these chemicals and the expression of 21 miRNAs was found 96 h after treatment. Among them, 14 miRNAs were differentially expressed due to the treatments with fipronil, triazophos and their mixture; 5 miRNAs showed altered expression level after treatment with formulations of these chemicals; miR-29b and miR-738 were differentially expressed after treatment with adjuvants. MiRNAs might present a novel toxicological response that could be used as a toxicological biomarker and have a different direction for future investigations of their association with miRNAs involved in chemical related diseases.  相似文献   
998.
铜、镉复合污染红壤对黑麦草生长和土壤酶活性的影响   总被引:2,自引:0,他引:2  
采用石灰石调节红壤酸性后,利用对铜、镉具有一定耐性的高产牧草黑麦草修复铜、镉复合污染土壤。分析黑麦草的生长、生理生化指标以及土壤中酶活性的变化,探索在修复铜、镉复合污染红壤的同时又满足饲料作物安全种植的土地利用方式。结果表明,对于弱酸性红壤(pH 6.0左右),土壤铜全量较低时(〈50 mg/kg),黑麦草的生物量、叶...  相似文献   
999.
为了探明硝基苯(NB)对硫酸盐还原的影响,揭示相关过程机制,采用以丙酸盐为碳源和电子供体的序批式厌氧反应系统(水力停留时间为33 h),考察了碳硫比为0.63~5.0,NB浓度为2.5~50 mg/L条件下,系统的硫酸盐还原效能。研究结果表明,NB对硫酸盐还原过程存在抑制作用,当系统NB进水浓度低于30 mg/L时,NB对硫酸盐还原过程抑制并不显著,但当进水NB浓度达50 mg/L时,硫酸盐还原率由近100%迅速降至17%。对比实验结果进一步表明,NB初始浓度为16.5 mg/L条件下,硫酸盐的比还原速率和丙酸的比消耗速率分别为对照组的63%和52%。硫酸盐还原的抑制主要源自NB及其还原产物苯胺(AN)的生物毒性,但上述抑制作用可逆。  相似文献   
1000.
以Fe(Ⅲ)-酒石酸配合物体系光化学过程中产生的Fe(Ⅱ)和.OH为主要检测对象,探讨了Fe(Ⅲ)-酒石酸配合物体系光化学反应的基本规律及影响因素。结果表明,体系的光化学过程能产生Fe(Ⅱ)和.OH;产生Fe(Ⅱ)的速率远高于产生.OH的速率;Fe(Ⅱ)生成浓度在pH 3.50时最大,.OH则在pH 3.00时最大;配合物的光化学过程中会伴随pH的升高;在照度为3.6×103Lux的日光灯照射下,Fe(Ⅲ)-酒石酸盐配合物初级光解的速率常数为2.1×10-3S-1;Fe(Ⅱ)是高价重金属的主要还原剂,.OH是有机物的主要氧化剂。  相似文献   
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