生物地耕法降解含油污泥的研究

对含油质量分数为9.0%和10.2%的油泥进行生物地耕法的研究。结果表明,生物降解120d后,油泥残油质量分数分别由9.0%和10.2%降至3.1%和4.0%,石油降解率分别为65.6%和60.8%;同时利用气相色谱-质谱分析生物降解前后含油污泥中饱和烃的组分和质量分数变化,含油质量分数为9.0%和10.2%油泥中的长链烷烃分别减少39.8%和42.2%。     

俄罗斯减压渣油超临界萃取残渣的催化加氢反应研究

以高压反应釜为反应器、环己烷为溶剂,选用分子筛、金属及舍金3大类共6种催化剂,对俄罗斯减压渣油超临界萃取所得残渣的非催化及催化加氢反应进行研究。结果表明,采用NKF-β型和Y型分子筛作为催化剂,残渣加氢反应产物中芳烃的相对含量超过55％;采用金属Fe、Ni以及合金Co—Fe、Pd—C作为催化剂,残渣加氢反应产物中正构烷烃的相对含量超过70％;除采用Fe和Pd—C作为催化剂的残渣加氢反应产物之外,在其他各组产物中均检测到少量含氧化合物,而在以NKF-β型分子筛作为催化剂的加氢反应产物中还检测出含氮化合物。针对各组加氢反应产物中化合物相对含量的差异,推测了残渣在不同类型催化剂作用下可能存在的反应途径。     

农村简易垃圾焚烧炉周边土壤二恶英分布研究

为了解农村简易生活垃圾焚烧炉排放废气中二恶英对周边地区的环境影响,对焚烧炉周边6个环境土壤及焚烧炉排放的飞灰和灰渣中二恶英的分布规律进行了研究.检测结果显示,焚烧炉周边环境土壤样品中二恶英国际毒性当量在2.29～9.45 ng/kg(干基)之间,高于背景值(0.537 I TEQ ng/kg).而焚烧炉排放的飞灰及灰渣中二恶英国际毒性当量分别为3 454和32.2 ng/kg.利用主成分分析方法,发现环境土壤中的二恶英来源较为复杂,焚烧炉污染物排放不是土壤中二恶英的唯一来源.     

脱硫灰与石灰石粉复合制备沥青填料研究

通过XRD及马歇尔稳定度试验等方法,研究把脱硫灰用作沥青复合填料。试验结果表明,以不大于40%的脱硫灰与石灰石粉复合可制备沥青填料,所制备的沥青混合料各项指标均能满足规范要求,可应用于沥青道路工程,其中以约30%脱硫灰取代石灰石粉所制备的复合沥青填料效果较好。     

Continuous ethanol production from wood hydrolysate by chemostat and total cell retention culture

Chemostat and total cell retention cultures with internal filter system ofSaecharomyc.es cerevisiae H1-7 were carried out to produce ethanol from wood hydrolysate. Maximum ethanol productivity obtained in a chemostat with the aeration rate of 1 vvm was 3.79 g/(L·h). This was 20% higher than that in a chemostat without aeration. However, the substrate was not completely consumed at the dilution rate with the maximum productivity. The realistic productivity, which has higher than 99% conversion rate of substrate, was. 2.95 g/(L·h). The maximum productivity in the total cell retention culture was 6.65 g/(L·h) at the dilution rate of 0.19 h¹ and the residual glucose concentration was negligible.     

超声波技术在农药残留研究中的应用

从超声波萃取和超声波降解两方面，综述了近几年国内外超声波技术在农药残留研究中的应用及研究现状。     

Mg~(2+)和氨基酸对重组大肠杆菌BL21(DE3)生长及羧肽酶原B表达的影响

目的研究Mg2+和氨基酸对重组菌株生长及表达pCPB的影响。方法通过摇瓶和发酵罐培养,观察不同Mg2+浓度和氨基酸对重组菌的生长和羧肽酶原B表达的影响。结果添加1g/L Mg2+能提高质粒的稳定性;添加氨基酸能使羧肽酶原B表达量由18·7g/L提高到24g/L。结论添加适量的Mg2+和氨基酸能促进重组菌的生长和提高目的蛋白的表达量。     

Crop residue,manure and fertilizer in dryland maize under reduced tillage in northern China: I grain yields and nutrient use efficiencies

The rapidly increasing population and associated quest for food and feed in China has led to increased soil cultivation and nitrogen (N) fertilizer use, and as a consequence to increased wind erosion and unbalanced crop nutrition. In the study presented here, we explored the long-term effects of various combinations of maize stover, cattle manure and nitrogen (N) and phosphorus (P) fertilizer applications on maize (Zea mays L.) yield and nutrient and water use efficiencies under reduced tillage practices. In a companion paper, we present the effects on nutrient balances and soil fertility characteristics. The ongoing factorial field trial was conducted at Shouyang Dryland Farming Experimental Station in northern China from 1993 onwards. The incomplete, determinant-optimal design comprised 12 treatments, including a control treatment, in duplicate. Grain yields and N, P, and potassium (K) uptakes and N, P and K use efficiencies were greatly influenced by the amount of rain during the growing season (GSR), and by soil water at sowing (SWS). There were highly significant interactions between GSR and added stover and manure, expressed in complex annual variations in grain yield and N, P and K use efficiencies. Annual mean grain yields ranged from 3,000 kg ha⁻¹ to 10,000 kg ha⁻¹ and treatment mean yields from 4,500 kg ha⁻¹ to 7,000 kg ha⁻¹. Balanced combination of stover (3,000–6,000 kg), manure (1,500–6,000 kg) and N fertilizer (105 kg) gave the highest yield. Stover and manure were important for supplying K, but the effects differed greatly between years. Overall mean N recovery efficiency (NRE) ranged from 28% to 54%, depending on N source. NRE in wet years ranged from 50% to 90%. In conclusion, balanced combinations of stover, manure and NP fertilizer gave the highest yield and NRE. Reduced tillage with adding stover and manure in autumn prior to ploughing is effective in minimizing labor requirement and wind erosion. The potentials of split applications of N fertilizer, targeted to the need of the growing crop (response farming), should be explored to further increase the N use efficiency.     

Some aspects of the carbonization of vacuum distillation residue from crude oil

These studies concern the carbonization process of residues from vacuum distillation of crude oil. Some explanation aspects of the hypothetic reaction mechanism controlling the carbonization of high molecular weight components of crude oil are developed. On the basis of numerous experimental investigations, the thermal decomposition process can be divided into two stages, the first, from 670 to 790 K, in which the decomposition reactions take place and low and medium weight molecular compounds are emitted and the second stage, from above 790 K to 1000 K, in which cyclization, condensation and aromatization processes take place, and the degree of structural ordering in the solid products increases.     

关于减法补数复合函数的均值估计

用初等方法和解析方法研究类似于Smarandache减法补数的复合函数性质,获得了3个较强的均值公式,完善了加法补函数与减法补函数在数论中的研究和运用。