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排序方式: 共有122条查询结果,搜索用时 31 毫秒
61.
论述了烟草企业烟叶仓库磷化铝杀虫的原理、特点及对火灾探测器的影响,根据现行的消防技术和各种火灾探测器的特点,提出了适用于烟叶仓库的火灾探测器选型方案,并提出了对火灾探测器进行防磷化铝腐蚀的改进方法。经过在杭州卷烟厂的试用表明,这种改进型的火灾探测器具有很强的防磷化铝腐蚀的特性。  相似文献   
62.
利用厌氧反应器技术+高效絮凝处理造纸法烟草薄片生产废水,CODCr可从6000mg/L降到2000mg/L以下,再用去除率高达90%的SBR序批式反应器技术进行深度处理,废水经处理可达标排放(CODCr≤100mg/L)。  相似文献   
63.
A pot experiment was conducted to study the e ects of arbuscular mycorrhizal (AM) fungi (from contaminated or uncontaminated soils) on arsenic (As) uptake of tobacco (Nicotiana tabacum L.) in As-contaminated soil. Mycorrhizal colonization rate, dry weight, As and P uptake by plants, concentrations of water-extractable As and As fractions were determined. A low mycorrhizal colonization rate (< 25%) was detected. Our research indicated that AM fungi isolated from polluted soils were no more e ective than those from unpolluted soils when grown in symbiosis with tobacco. No significant di erences were observed in roots and stalks dry weights among all treatments. Leaves and total plant dry weights were much higher in Glomus versiforme treatment than that in control treatment. As contents in roots and stalks from mycorrhizal treatments were much lower than that from control treatment. Total plant As content exhibited the same trend. P concentrations in tobacco were not a ected by colonization, nor were stalks, leaves and total plant P contents. Roots P contents were remarkably lower in HN treatments than in other treatments. Meanwhile, decreased soil pH and lower water-extractable As concentrations and higher levels of As fraction bound to well-crystallized hydrous oxides of Fe and Al were found in mycorrhizal treatments than in controls. The protective e ect of mycorrhiza against plant As uptake may be associated with changes in As solubility mediated by changing soil pH. These results indicated that under As stress, proper mechanisms employed by AM fungi can protect tobacco against As uptake. Results confirmed that AM fungi can play an important role in food quality and safety.  相似文献   
64.
湖南某植烟土壤重金属含量及其生态风险评价   总被引:4,自引:0,他引:4  
采集了湖南某植烟区表层土壤样品112份,测定了土壤中6种重金属元素的含量,并采用单因子污染指数法、综合污染指数法和潜在生态危害指数法对其污染状况进行评价.结果表明,植烟区土壤重金属平均含量分别为36.25(Cu)、69.78(Zn)、37.66(Pb)、0.36(Cd)、12.71(As)、0.27(Hg)mg·kg-1.6个元素的变异系数在32.57%—59.03%之间,属于中等变异,元素分布不均.污染评价结果表明,植烟区土壤重金属Cu、Zn、Pb、As的单因子污染指数平均值小于1,其污染较轻.而重金属Cd和Hg的超标率为54.46%和58.04%,土壤受到Cd和Hg污染.潜在生态风险指数评价结果显示植烟区土壤重金属属于轻度污染.相关性分析结果表明Cu、Zn、Pb和Cd之间呈显著相关性,As和Hg相关性显著,说明其同源性较高.来源分析表明,研究区Cu、Zn、Pb和Cd污染来源东北部主要为矿区污染,西南部主要是人为源,As主要来源为成土母质和生活源,Hg主要为大气污染源.  相似文献   
65.
污水稳定塘菌-藻生态系统去除与灭活植物病毒TMV研究   总被引:4,自引:0,他引:4  
了解污水稳定塘生态系统去除与灭活植物病毒的效率与机理具有重要的理论和实际意义.对模型植物病毒———烟草花叶病毒(tobaccomosaicvirus,TMV)的实验结果显示:稳定塘系统中的悬浮固体(SS)可在短时间内吸附TMV且达到一个饱和值.纯培养的枯草芽孢杆菌及小球藻对TMV的存活无明显不良影响,而光合细菌和稳定塘中的混合细菌群却对TMV具有灭活作用.当它们同藻类形成菌藻共生体系时,对TMV的灭活速率分别从对照的每天0 0404log10(枯斑数·mL-1)升高到0 0783log10(枯斑数·mL-1)和0 075log10(枯斑数·mL-1) 因此,在污水稳定塘生态系统中,由于病毒对悬浮固体的吸附以及菌藻共生体系中微生物的作用可有效地去除与灭活植物病毒,其中悬浮固体吸附病毒并非真正意义上的灭活,稳定塘中存在的细菌特别是光合细菌对植物病毒的灭活才是最主要的因素.  相似文献   
66.
对Ri质粒转化烟草的影响因素进行研究,以期获得较为理想的实验系统,用发根农杆菌介导,将豌豆凝集素基因导入烟草,获得转基因的烟草发根,GUS组织化学染色,蛋白免疫原位杂交证明,gus报告基因和豌豆凝集素基因已在转基因烟草发根中得到了转译表达,本结构将为瘤菌能否扩大宿主范围,为研究烟草与豌豆根瘤菌相互作用,结瘤固氮的可能性奠定基础。  相似文献   
67.
Evaluation of visual symptoms of ozone damage was conducted in the network of bioindicator rural stations of Catalonia (NE Spain) every 14 days from May to October. Damage rates of ozone (and consequently, ozone biomonitoring capacity of bioindicators) were found to vary highly in time and space depending on the local environmental and meteorological conditions. Lower ozone damage to foliage was produced when meteorological conditions favour stomata resistance. Modulatory effects of meteorological conditions need to be considered in biomonitoring and when modeling plant ozone doses and damage.  相似文献   
68.
1997~1998年在广东省五华县的紫色土田进行了烤烟优质高产施肥试验。结果表明,在一定的氮磷施用量条件下,烤烟的产量、质量及产值都是随着施钾比例的提高而提高。在一定的配比下,烤烟的产量及产值在施氮 165 kg/hm~2以下均随施氮量的增加而提高;均价和优级烟率以中等氮水平( 135 kg/hm~2)的为最高。本文还提出烤烟的最佳施肥方案。  相似文献   
69.
Measurements of indoor and outdoor PM10, as well as indoor O3 and CO concentrations were conducted and are presented here. These measurements were carried out at an institute building, located in a suburban industrial area in Greece. Both indoor and outdoor PM10 samples were also collected and their elemental composition was identified by ED-XRF analysis. Twenty seven major, minor and trace elements were identified. The measurements took place generally in different periods of institute operation, from June 2004 to February 2005. The indoor PM10 concentrations which were measured during the normal operation period of the institute were found to be many times higher than the respective outdoor PM10 concentrations of the same periods. On the contrary, the indoor PM10 concentrations which were measured during the holiday period were found to be lower than their corresponding outdoor values. Indoor O3 and CO concentrations were found to be in low level. Indoor PM10 concentrations were found to be in a relative good correlation with O3 (r = 0.45) and in high correlation (r = 0.98) with CO concentrations. On average, total elements concentrations were much higher indoors relative to outdoors. Based on above findings we attempted to determine the pollution sources of the indoor environment and to investigate some parameters or chemical processes that affect indoor pollutants’ levels.  相似文献   
70.
为探究烟秆生物炭(TSB)和磷酸氢二铵(DHP)对微碱性土壤镉(Cd)迁移转化机制,通过盆栽试验调查了其施用对土壤pH、有效态Cd、Cd赋存形态和小麦Cd积累的影响.结果表明:① TSB和DHP显著降低了土壤有效态Cd含量,10.12 t·hm-2TSB可降低微碱性土壤(pH 7.8)有效态Cd含量的44%.② TSB和DHP显著改变了土壤Cd的赋存形态,6.75 t·hm-2和10.12 t·hm-2TSB分别降低可交换态Cd含量的48%和42%,分别增加铁锰氧化物结合态Cd和有机结合态Cd含量的47%~67%和22%~38%.所有处理均增加了残渣态Cd含量,以TSB和DHP配施增幅最大,为115%~217%.③ TSB和DHP显著降低小麦根系、叶片、叶鞘、茎秆、颖壳和籽粒Cd含量.10.12 t·hm-2 TSB小麦籽粒Cd含量降低56%,产量不受影响.10.12 t·hm-2TSB和DHP配施小麦可增产32%,籽粒Cd含量降低53%.结果说明在微碱性土壤上施用TSB和DHP可促进土壤Cd的形态转化,降低土壤Cd的生物有效性,降低小麦籽粒Cd积累.  相似文献   
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