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51.
通过测定液体与废白土粉末之间的接触角及液体与蜡之间的液液界面张力,对水基表面活性剂乳液的溶剂及配方进行了优选,得到最佳的水基面活性剂乳液的组成为:质量分数0.2%的十二烷基苯磺酸钠+体积分数为2.5%的乙醇+体积分数为25%的混合烃(正己烷+苯,等体积)+体积分数为72.5%的水。实验证明,用该水基表面活性剂乳液处理废白土,蜡的回收率可达80%,同时不破坏白土的颗粒结构。  相似文献   
52.
Climatic changes can be separated into two parts: natural changes -and human activity influenced on climatic changes. The observed data could not only show the effects caused by human activity. Several simulated results as simulated by the GCMs induced by the greenhouse effects in China .have been analysed. It is shown that an obvious warming of about 3-6℃ in winter and 2-5℃ in summer in China as simulated by the GCMs induced by doubling CO2 have been found. There are getting drier or wetter regions in China due to doubled CO2 as simulated by most of models. Comparing the simulated results with the observed data in China, some simulated results are able to be believed. The GCMs should be improved, especially in the regional areas.  相似文献   
53.
Effects of pH, temperature, and oxygen on the production and release of phosphine in eutrophic lake sediments were investigated under laboratory tests. Results indicated that the elimination of matrix-bound phosphine was accelerated under initial pH 1 or 12. Phosphine levels could reach maximum under initial pH 10. The contents of phosphine increased with the addition of alkali under pH 4–12. The rates of phosphine production and release from lake sediments varied with temperature. 20°C was the most favorable temperature for the production of matrix-bound phosphine. Oxygen showed little effect on matrix-bound phosphine. Matrix-bound phosphine concentrations in lake sediments were concluded to be dependent on a balance of natural generation and depletion processes. Translated from Acta Scientise Circumstantiae, 2005, 25(5): 681–685 [译自: 环境科学学报]  相似文献   
54.
In this study, the two-stage upflow anaerobic sludge blanket (UASB) system and batch experiments were employed to evaluate the performance of anaerobic digestion for the treatment of high concentration methanol wastewater. The acid resistance of granular sludge and methanogenic bacteria and their metabolizing activity were investigated. The results show that the pH of the first UASB changed from 4.9 to 5.8 and 5.5 to 6.2 for the second reactor. Apparently, these were not the advisable pH levels that common methanogenic bacteria could accept. The methanogenic bacteria of the system, viz. Methanosarcina barkeri, had some acid resistance and could still degrade methanol at pH 5.0. If the methanogenic bacteria were trained further, their acid resistance would be improved somewhat. Granular sludge of the system could protect the methanogenic bacteria within its body against the impact of the acidic environment and make them degrade methanol at pH 4.5. The performance of granular sludge was attributed to its structure, bacteria species, and the distribution of bacterium inside the granule. Translated from Acta Scientiae Circumstantiae, 2004, 24(4): 633–636 [译自: 环境科学学报]  相似文献   
55.
机动车排出物对人体健康危害的研究   总被引:9,自引:1,他引:9  
运用基因、DNA、染色体,细胞和整个动物为终点的远期危害测试系统,对各类机动车排出尾气的有机提取物的致突变性及潜在致癌性进行了评估,同时运用流行病学方法对接触人群进行调查,结果表明:(1)柴油车,助动车的颗粒有机提取物包含100多种化学物,(2)Ames、UDS微核及SHE细胞恶性转化试验为阳性结果,具有突变性及致癌性。(3)它们能使人胚细胞形成转化灶并发现其中的c-myc,p21及bcl-2表达  相似文献   
56.
柴油机排放碳颗粒物的催化燃烧   总被引:6,自引:0,他引:6  
在热天平装置上考察了柴油机和碳颗粒物燃烧催化剂的活性,讨论了样品制备因素对样品失重的影响,这些因素包括碳颗粒物组成、催化剂栽体、催化剂与碳颗粒物质量比,着重筛选了催化剂的组份,得到了组份催化剂CuCl2-KCo-NH4VO3其550℃焙烧后能使样品的Tm和Tf值都降低180℃以上,并对催化剂的热稳定性进行了研究。  相似文献   
57.
沼泽红假单胞菌H3对酸性红B2GL染料的厌氧脱色和降解作用   总被引:7,自引:0,他引:7  
从印染厂污泥中分离到一株沼泽红假单胞菌(RhodopseudomonaspalustrisH3),在光照厌氧条件下该菌生长细胞可将100mg/L酸性红B2GL染料去除到30mg/L.完整细胞脱色的最适条件为pH70,温度30℃,细胞浓度20—25mg/mL(湿重).低浓度的阳离子对脱色影响不大.在通Ar气使严格厌氧和加有还原性辅酶I的条件下无细胞提取液的脱色活性最高,比活率为154×10-2mg/(mg·h).根据降解产物的分析,推断了该菌对酸性红染料的降解代谢途径.  相似文献   
58.
Stratigraphy, lithology and depositional structures of Liassic red limestone-breccias of the Adnet Formation, including the 'Adnet Scheck', were studied at several outcrops of the Northern Calcareous Alps (NCA) south-east of Salzburg. A four-fold lithostratigraphic division is proposed for the Adnet Formation of the Osterhorn Mountains: the hemipelagic Schmiedwirt (Sinemurian) and Kehlbach (Carixian) members are separated from the pelagic Saubach Member (Toarcian) by a layer of amalgamated breccias (Scheck Member, probably Domerian to early Toarcian). Several other breccia beds occur locally from the base of the Kehlbach Member up to the lower Saubach Member. Although the sediments overlying the Scheck Member breccias are of coeval age, the ages of the underlying strata are very different. This can be explained by submarine Liassic erosion during a period of resedimentation from the middle Carixian until the early Toarcian. At least 10–15?m of partly lithified sediments were eroded by gravity flows. The entire Kehlbach Member and up to two-thirds of the Schmiedwirt Member were removed at Adnet. The breccias originated from submarine debris flows. Repeated flows over a long period and the depositional setting exclude a triggering by sea-level fluctuations. Most probably they arose from tectonically triggered slumps and slides of superficial sediments. The 'Scheck' was initiated on the steep upper slope of the drowned Triassic Adnet reef and flowed to the north-east.The Pliensbachian to early Toarcian period of tectonic activity indicated by the breccias was the most important during the Liassic in the Osterhorn Mountains and other parts of the NCA. From the large-scale regional distribution of the breccias and in accord with published data, a roughly north-east trending strike-slip fault zone is proposed, crossing the NCA south of the Osterhorn block, with a peaking activity during the Pliensbachian to early Toarcian as the cause of the tectonic movements.  相似文献   
59.
Single zircons from two orthogneiss complexes, the Grey Gneiss and Red Gneiss, the lowermost tectonic units in the Erzgebirge, were dated. The grey Freiberg Gneiss is of igneous origin and has a 207Pb/206Pb emplacement age of 550±7 Ma. A quartz monzonite from Lauenstein contains idiomorphic zircons with a mean 207Pb/206Pb age of 555±7 Ma as well as xenocrysts ranging in age between 850 and 1910 Ma. Red gneisses from the central Erzgebirge contain complex zircon populations, including numerous xenocrysts up to 2464 Ma in age. The youngest, idiomorphic, zircons in all samples yielded uniform 207Pb/206Pb ages between 550±9 and 554±10 Ma. Nd isotopic data support the interpretation of crustal anatexis for the origin of both units. Nd(t) values for the grey gneisses are –7.5 and –6.0 respectively, (mean crustal residence ages of 1.7–1.8 Ga). The red gneisses have a wider range in Nd(t) values from –7.7 to –2.8 (T DM ages of 1.4–1.8 Ga). The zircon ages document a distinct late Proterozoic phase of granitoid magmatism, similar in age to granitoids in the Lusatian block farther north-east. However, Palaeozoic deformation as well as medium pressure metamorphism ( 8 kbar/600–650° C) are identical in both gneiss units and distinguish these rocks from the Lusatian granitoids. The grey and red gneisses were overthrust by units with abundant high-pressure relicts and a contrasting P-T evolution. Zircon xenocryst and Nd model ages in the range 1000–1700 Ma are similar to those in granitoid rocks of Lusatia and the West-Sudetes, and document a pre-Cadomian basement in parts of east-central Europe that, chronologically, has similarities with the Sveconorwegian domain in the Baltic Shield.  相似文献   
60.
涕灭威在植物和土壤中的移动与分布   总被引:3,自引:0,他引:3  
报道了涕灭威在花生、棉花、柑橘和土壤中的吸收、运转和分布。结果表明,涕灭威及其代谢物在柑橘叶子中的残留40d达到最高峰(3.449ppm),可食部位的残留范围为0-0.089ppm,低于美国EPA规定的MRL。涕灭威在土壤中降解较快,半衰期约1周。收获时土壤中的检出范围为0-0.157ppm。涕灭威及其代谢物水溶性很强,且具有渗透和扩散性,因此使用不当可能造成地下水污染。  相似文献   
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