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81.
转炉渣诱导磷酸钙结晶法去除和回收废水中磷的研究   总被引:1,自引:0,他引:1  
以转炉渣为晶种材料,利用批次结晶沉淀实验,研究不同的反应条件对诱导磷酸钙结晶法去除和回收废水中磷的影响。结果表明,最优反应条件为:pH=9.5,Ca/P摩尔比2∶1,转炉渣用量1.7 g/L,反应时间3 h,在此条件下,碳酸根对反应的影响甚小,对养猪场废水和污泥浓缩池上清液的处理,最高去除率分别达到95.36%和96.54%;转炉渣循环利用10次,回收磷的效果仍然很好。运用扫描电子显微镜(SEM)、X射线能谱仪(EDS)和X射线衍射仪(XRD)等测试手段对在最优工艺条件下重复使用10次的转炉渣进行了表征,证明回收的磷主要以羟基磷灰石(HAP)形态存在。  相似文献   
82.
以扬州第四水厂沉淀后的出水作为原水,模拟突发LAS污染,通过投加碳基高价银分子晶体电池进行应急处理的实验研究。实验结果表明:碳基高价银分子晶体电池对LAS的吸附,在30min内能达到81%的吸附容量;碳基高价银分子晶体电池对LAS的吸附,符合Freundlich吸附模式;溶液pH小于5时,吸附效果较好;对进水浓度小于4.75mg/L的LAS污染水样,接触时间在10min以内,便能使出水中LAS的浓度达到生活饮用水0.3mg/L的限值。  相似文献   
83.
罗晓  岳琳  洪纲  刘艳芳 《化工环保》2014,34(1):37-40
采用转鼓铁碳微电解法预处理液晶生产废水,优化了工艺参数,并进行了装置连续运行试验。结果表明:保持转鼓转速2 r/min,在废水pH=2.0、铁碳比(m(铸铁屑)∶m(活性炭))1∶1.5、填料装填率(填料体积与反应器有效容积之比)1∶10、HRT=3 h的优化工艺条件下,废水BOD5/COD由处理前的0.181提高到0.265;电解装置连续运行30 d,COD去除率稳定在40.1%~43.2%之间,且填料未出现板结现象。  相似文献   
84.
根据卫星遥感数据的分辨率、采集频次、获取方式等特点,将MODIS卫星遥感数据应用到渤海海冰遥感监测中。通过海冰在可见光和红外光波段的光谱存在特定差异的特性,对海冰发生面积进行提取。同时对渤海海冰进行了遥感监测,并完整地监测到海冰从发生到极盛再到消退的全过程。同时,在海冰发生最为严重的时段,对辽东湾海域进行了密集监测。研究结果表明,MODIS卫星遥感数据在海冰监测中有着及时、准确的优势。  相似文献   
85.
Quartz crystal nanobalance (QCN) technique is considered as a powerful mass sensitive sensor for monitoring of materials in the sub-nanogram level. In the current study, a method based on QCN technique developed to determine Telone in air. Various coating materials including methyl phenyl silicon, 75% phenyl (OV25) and molecularly imprinted polymer (MIP) were employed. The frequency shift of OV25-modified quartz crystal was found to be linear against organohalogen compounds [Telone (soil fumigant), Koril (Herbicide), Endosulfan (organochlorine insecticide) and Chloroform (solvent)] concentrations in the range of 2.4 to 48 mg L?1 for Telone vapor and 4.8–24 mg L?1 for three other vapors. The correlation coefficients for Telone, Koril, Endosulfan and Chloroform were 0.992, 0.996, 0.989 and 0.991, respectively. The principal component analysis was also utilized to process the frequency response data of the organic vapors. Using principal component analysis, it was found that more than 93.85% of the data variance could still be explained by use of two principal components (PC1 and PC2). Subsequently, the successful discrimination of Telone and other compounds was quite possible through the principal component analysis of the transient responses of the OV25-modified electrode. In the second method, a molecularly imprinted polymer-coated sensor for Telone was developed. Molecularly imprinted polymer coated quartz crystal (MIP-QCN) showed a selective response to Telone and gave a linear relationship between frequency shift and amount of Telone from 1 to 48 mg L?1. In this investigation, the proficiency of MIP-QCN and OV25-modified QCN sensors were compared.  相似文献   
86.
利用无机溶液对废液晶显示屏的玻璃基板回收工艺作了初步的探索,根据回收处理的难易,简单地将废弃液晶显示屏分为3类:含树脂黑色矩阵膜的上层玻璃基板可以采用氢氧化钠直接浸泡处理、含铬黑矩阵膜的上层玻璃基板和下层玻璃基板可以先用氢氧化钠溶液浸泡去除偏光片,再用氢氟酸溶液浸泡处理。结果表明,利用无机溶液处理可以较快得到干净的玻璃基板,而且工艺简单、成本低。  相似文献   
87.
Andrews C  Dick J  Jonasson C  Callaghan T 《Ambio》2011,40(6):600-609
A 30-year series (1978–2007) of photographic records were analysed to determine changes in lake ice cover, local (low elevation) and montane (high elevation) snow cover and phenological stages of mountain birch (Betula pubescens ssp. czerepanovii) at the Abisko Scientific Research Station, Sweden. In most cases, the photographic-derived data showed no significant difference in phenophase score from manually observed field records from the same period, demonstrating the accuracy and potential of using weekly repeat photography as a quicker, cheaper and more adaptable tool to remotely study phenology in both biological and physical systems. Overall, increases in ambient temperatures coupled with decreases in winter ice and snow cover, and earlier occurrence of birch foliage, signal a reduction in the length of winter, a shift towards earlier springs and an increase in the length of available growing season in the Swedish sub-arctic.  相似文献   
88.
Abstract: In northern regions, large volumes of water are needed for activities such as winter road construction. Such withdrawals, particularly from small lakes, can reduce oxygen concentrations and water levels, potentially affecting aquatic organisms. Withdrawal limits have been developed by regulatory agencies, but are largely theoretical. Water withdrawal thresholds were tested in two small lakes by removing 10% and 20% of their respective under‐ice volumes and comparing oxygen parameters, temperature, over‐wintering habitat, and northern pike (Esox lucius) abundance to reference conditions. Because of a milder winter, oxygen parameters were elevated in reference lakes in the period following withdrawal compared to the prewithdrawal period. The 10% withdrawal resulted in a ?0.2 m shift in the oxygen concentration profile at 4 mg/l in that lake, but had no effect on total volume‐weighted oxygen, or volume of over‐wintering habitat. In contrast, the 20% withdrawal caused 0.7 m reduction in the oxygen concentration profile at 4 mg/l compared to the previous year, a 26% decline in the volume‐weighted oxygen concentration, and a 23% reduction in the volume of over‐wintering habitat compared to prewithdrawal conditions. Water temperatures were slightly (≤ 10%) colder in the upper strata in the year following the withdrawal in both withdrawal and reference lakes. Northern pike abundance was not impacted by water withdrawals in either of the lakes. The results of this study show that the effects of water withdrawal on the parameters investigated reflected the characteristics of the lakes, and would therefore be expected to vary from lake to lake. Policy development to mitigate impacts must therefore reflect the site‐specific nature of water withdrawal.  相似文献   
89.
Abstract: Water resources are limited in many areas of the North Slope, Alaska, particularly during winter. Water is used by the oil industry for ice road construction and maintenance, drilling and facility operations, and potable water supplies. The coastal plain between Teshekpuk Lake, in the National Petroleum Reserve‐Alaska (NPR‐A) and the Colville River has numerous shallow lakes, but further south in the northern foothills of the Brooks Range, and east to the Canning River, lakes are fewer. While many oil and gas lease sales have been conducted, or are proposed, access to the leases may be limited because of the lack of available water for ice road construction. Ice roads are the main means by which exploration is conducted in the Arctic, putting a stress on freshwater bodies that do not freeze to the lakebed in winter. Lakes that do not freeze to the lakebed also serve as overwintering habitat for fish. The purpose of this paper is to report on the potential distribution of water bodies that may provide overwinter water in selected areas from Teshekpuk Lake to the Canning River. The project used synthetic aperture radar (SAR) imagery to search for the presence of water in lakes in March 2006. In the Kuparuk and Canning SAR images, 52 and 61% of lakes were frozen to their beds by March 2006, accounting for 49 and 57% of the lake area in these study regions. Conversely, only 2% of the lakes in the Teshekpuk region were frozen to the bottom by March 2006. Unfrozen water was more available because of deeper and more numerous lakes in the Teshekpuk Lake region (west) than in the Canning River area (east). While only specific SAR tiles were analyzed herein, the method will be a useful tool for land managers who seek to evaluate the potential for ice road construction across the Arctic.  相似文献   
90.
Abstract: Arctic lakes are significant emitters of methane (CH4), a potent greenhouse gas, to the atmosphere; yet no rigorous quantification of the magnitude and variability of pan‐Arctic lake emissions exists. In this study, we demonstrate the potential for a new method using synthetic aperture radar (SAR) imagery to detect methane bubbles in lake ice to scale up whole‐lake measurements of CH4 ebullition (bubbling) to regional scales. We estimated ebullition from lakes, which is often the dominant mode of lake emissions, by mapping the distribution of bubble clusters frozen in early winter ice across surfaces of seven tundra lakes and one boreal forest lake in Alaska. Applying previously measured ebullition rates associated with four distinct classes of bubble clusters found in lake ice, we estimated whole‐lake emissions from individual lakes. The percent surface area of lake ice covered with bubbles (R2 = 0.68) and CH4 ebullition rates from lakes (R2 = 0.59) and were correlated with radar return values from RADARSAT‐1 Standard Beam mode 3 for the tundra lakes, suggesting that with appropriate scaling and consideration for variability in lake‐ice conditions, this technique has the potential to be used for estimating broader‐scale regional and pan‐Arctic lake methane emissions.  相似文献   
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