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181.
This paper reviews the status quo of the research on electromagnetic radiation in gas-containing coal and rock fracture. It focuses mainly on the electromagnetic radiation phenomena, the generation mechanism, characteristics, law of change and experimental applications in the field. Based on the authors’ research work in the past decade, detailed discussions are made with respect to the engineering applications of electromagnetic radiation spectrum, law of transmission and signal collection of gas-containing coal and rock. Furthermore, the paper gives the prospect of electromagnetic radiation effects in coal and rock fracture and its applications.  相似文献   
182.
煤矸石的改性及其对稀土生产废水中氨氮的吸附   总被引:1,自引:0,他引:1  
采用热改性、盐酸改性、硫酸改性、碱改性的方法分别制备了4种改性煤矸石吸附剂,研究了吸附工艺条件对4种改性煤矸石吸附剂对稀土生产废水中氨氮去除效果的影响以及吸附机理.实验结果表明:4种改性煤矸石吸附剂吸附氨氮的最佳工艺条件为:吸附剂加入量0.02 g/mL,振荡时间2.5 h,废水pH 7~8;4种吸附剂氨氮去除率大小顺序为:碱改性煤矸石>硫酸改性煤矸石>盐酸改性煤矸石>热改性煤矸石;碱改性煤矸石的氨氮去除率最高,为59.19%;碱改性煤矸石吸附剂对含氨废水中氨氮的吸附较好地符合Langmuir方程和Freundlich方程,在一定程度上符合Temkin方程.  相似文献   
183.
Reliable estimation of nutrient concentrations is required to manage animal manure for protecting waters while sustaining crop production. This study was conducted to investigate sample variability and reliable nutrient analysis for several manure types and handling systems. Serial samples were collected from dairy, swine, and broiler poultry operations while manure was being loaded onto hauler tanks or spreaders for field application. Samples were analyzed for total solids (TS), total nitrogen (N), ammoniacal nitrogen (NH4-N), total phosphorus (P), and potassium (K). The least number of samples needed for reliable testing of total N and P, defined as +/- 10% of the experimental means with 99% probability, was obtained for each farm using a computer-intensive random resampling technique. Sample variability within farms, expressed as the coefficient of variation (CV), was mostly 6 to 8% for farms that used agitation of manure storages but several times higher (20-30%) on farms where no agitation was applied during the sampling period. Results from the random resampling procedure indicated that for farms that used agitation, three to five samples were adequate for a representative composite for reliable testing of total N and P; whereas for farms without agitation, at least 40 samples would be required. Data also suggest that using book values for manure nutrient estimations could be problematic because the discrepancies between book standards and measured farm data varied widely from a small amount to several fold.  相似文献   
184.
A pure culture using benzene as sole carbon and energy sources was isolated by screening procedure from gasoline contaminated soil. The analysis of the 16S rDNA gene sequence, morphological and physiological characteristics showed that the isolated strain was a member of genus Bacillus cereus. The biodegradation performance of benzene by B. cereus was evaluated, and the results showed that benzene could be e ciently biodegraded when the initial benzene concentration was below 150 mg/L. The metabolites of anaerobic nitrate-dependent benzene oxidation by strain B. cereus were identified as phenol and benzoate. The results of substrate interaction between binary combinations for benzene, phenol and benzoate showed that the simultaneous presence of benzene stimulated the degradation of benzoate, whereas the addition of benzene inhibited the degradation of phenol. Benzene degradation by B. cereus was enhanced by the addition of phenol and benzoate, the enhanced e ects were more pronounced at higher concentration. To our knowledge, this is the first report that the isolated bacterial culture of B. cereus can e ciently degraded benzene under nitrate reducing conditions.  相似文献   
185.
武汉分公司延迟焦化装置于1998年建成投产,处理量为40×104 t/a,2003年处理量扩大到100×104 t/a.装置外排污水一直是污水治理难点,含油污水的重质污油多次造成堵塞污水管线和污水处理场细菌大面积死亡的事故,外排的工业废水和雨水也对周边环境造成污染.  相似文献   
186.
Ordered mesoporous carbon(OMC) with high specific surface area and large pore volume was synthesized and tested for use as an adsorbent for volatile organic compound(VOC)disposal. Benzene, cyclohexane and hexane were selected as typical adsorbates due to their different molecular sizes and extensive utilization in industrial processes. In spite of their structural differences, high adsorption amounts were achieved for all three adsorbates, as the pore size of OMC is large enough for the access of these VOCs. In addition, the unusual bimodal-like pore size distribution gives the adsorbates a higher diffusion rate compared with conventional adsorbents such as activated carbon and carbon molecular sieve. Kinetic analysis suggests that the adsorption barriers mainly originated from the difficulty of VOC vapor molecules entering the pore channels of adsorbents. Therefore, its superior adsorption ability toward VOCs, together with a high diffusion rate, makes the ordered mesoporous carbon a promising potential adsorbent for VOC disposal.  相似文献   
187.
用动态的观点进行环境综合质量评价   总被引:27,自引:0,他引:27       下载免费PDF全文
强调用动态的观点进行环境质量评价,着重对如何从方法上体现这种观点进行了探索,提出了“变权”思想,设计了“权”调整公式,并依此对新疆库尔勒市环境综合质量进行了评价,其结果表明该方法在实际应用中是可行的,也是较合理的。  相似文献   
188.
考察了自制ZSM-5分子筛对甲苯气体的吸附-脱附性能,并与市售MCM-22分子筛进行了对比实验。实验结果表明:在吸附温度为25℃、进口甲苯质量浓度为840mg/m3、吸附气体流速为0.016m/s、床层高度为15cm的条件下,出口甲苯质量浓度达到0.8mg/m3时的穿透时间为82min,吸附效率为4.26mg/g;在脱附温度为80℃、脱附气体流速为0.016m/s的条件下,脱附35min时出口甲苯质量浓度达到最大,为1220mg/m3。自制ZSM-5分子筛的吸附-脱附性能优于市售MCM-22分子筛。  相似文献   
189.
以筛选出能够高效降解黑臭废水的更多细菌为目的,从不同重污染水体和底泥中筛选获得了多种细菌,并对其降解能力进行检测。净化实验结果表明,筛选出的50多株细菌中有12株对废水COD有明显的降解效果,降解率在45%以上;有4株菌对废水氨氮有明显的降解效果,降解率在30%以上,其中4号菌株对COD和氨氮都有很高的降解能力。经16SrRNA基因鉴定,4号菌株为不动杆菌属,由单因子优化实验得出4号菌株生长的最适条件为:温度30℃,pH7.5,转速180r/min,培养时间为22h时,微生物达到稳定期。在此条件下,4号菌株对自然黑臭废水COD和氨氮的降解率可达到92%和72%。  相似文献   
190.
富营养化湖泊沉水植物严重退化,可溶性无机碳DIC(Dissolved Inorganic Carbon)缺少是一个重要因素.本实验选择碳酸氢根形态DIC(HCO3-DIC)对苦草进行处理,设计了不同的HCO3-DIC添加晕(0、10、20mg·L-1)和营养水平N、P(N0.96、1.92、2.88、3.84mg·L-1,NH4--N:NO3--N=1:3,N:P=27)的交义实验,研究不同营养水平下HCO3--DIC对苦草(Vallisneria natans)的生理生态影响.实验证明,苦草幼苗在生长过程中可以不断吸收水体中的DIC,经15 d培养,培养液中DIC从16.91 mg·L-1下降到6.27 mg·L-1.21 d的实验结果显示,相同营养条件下高质量浓度HCO3--DIC组苦草相对生长率RGR(Relative Growthgate)高于其他组;无外加HCO3--DIC组过氧化物酶POD(peroxidase)活性随营养水平增加,从2.01 U·mg-1增至4.03 U·mg-1,相同营养水平下POD活性随HCO3--DIC增加而降低,说明水体营养水平的增高加剧了对苦草生长的胁迫,而HCO3--DIC大大减少和缓解了这种胁迫作用;中营养条件下,较低水平的HCO3--DIC质量浓度已经满足苦草叶绿素合成,而在重富营养时较高质量浓度的HCO3--DIC可以促进苦草叶绿素合成,缓解营养胁迫的黄化效应.研究揭示,水体HCO3--DIC增加可以缓解富营养化对沉水植物的胁迫作用.  相似文献   
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