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51.
为了准确评估堆场存储能力和合理选择疏浚泥处理工艺,以泥沙运动学为理论基础,将疏浚泥颗粒分为d0.005 mm、0.005 mm≤d≤0.01 mm和d0.01 mm 3个粒组,分析了各粒组相对含量的沿程变化规律,明确了堆场疏浚泥分选的主要原因是d0.01 mm粒组与0.005 mm≤d≤0.01 mm粒组的相对运动;以分选系数量化堆场疏浚泥分选的显著程度,以偏离系数量化原泥颗粒组成对堆场疏浚泥分选的影响,分析了分选系数、偏离系数分布与堆场疏浚泥土性分布的关系,提出了堆场疏浚泥分选特性的初步量化方法。研究结果表明:随着离吹填口距离的增大,分选系数沿程减小,呈幂函数分布,堆场疏浚泥分选性沿程减弱,吹填口附近分选系数最大,颗粒分选显著,粒度差异大,退水口附近分选系数趋近于零,分选不明显,颗粒分布均匀;偏离系数沿程先减小后增大,呈勺形分布,反映堆场前、后段疏浚泥土性与原泥相差较大,而堆场中段疏浚泥土性与原泥接近;分选系数、偏离系数的沿程分布与堆场疏浚泥土性分区具有良好的相关性。 相似文献
52.
The rates of absorption of CO2 into water and 0.1 kmol/m3 aqueous solutions of MEA, DEA and AMP were measured in a stirred cell with a flat gas-liquid interface in the presence of fine activated carbon particles. Experiments showed that the rates of absorption increased significantly with increases in the loading of activated carbon up to about 6 kg/m3 and thereafter remained constant. 相似文献
53.
Vanesa Losada Jorge Barros‐Velzquez Jos M. Gallardo Santiago P. Aubourg 《European Journal of Lipid Science and Technology》2004,106(12):844-850
Slurry ice is a biphasic system consisting of small spherical ice crystals surrounded by seawater at subzero temperature. Its effect on lipid damage (hydrolysis and oxidation) was evaluated during the chilled storage of a fatty fish species, sardine (Sardina pilchardus). Slurry ice treatment was checked alone and in combination with ozone and compared to traditional flake icing during a 22‐day storage. Different lipid damage indices (free fatty acids, FFA; peroxide value, PV; thiobarbituric acid index, TBA‐i; fluorescent compounds, FR) were checked and compared to sensory assessment and nucleotide degradation (K value). According to lipid hydrolysis (FFA) and oxidation (PV and FR) developments, slurry ice showed an inhibitory effect (p <0.05) on lipid damage during storage, as well as an inhibition of nucleotide autolytic degradation. Ozonised slurry ice did not provide differences (p >0.05) from slurry ice alone when considering lipid hydrolysis, nucleotide degradation and some lipid oxidation indices (PV and FR), although a higher (p <0.05) TBA‐i was observed at day 22 of storage when compared to flake ice and slurry ice treatments. However, a lower (p <0.05) fluorescence development was observed for fish treated under ozonised slurry ice when compared to traditionally iced fish. Sensory assessment showed a higher shelf life for fish samples treated under ozonised slurry ice than for their counterparts under slurry ice (15 d versus 12 d), while flake icing led to a far shorter shelf life (5 d). According to sensory and biochemical (lipid matter and nucleotide) analysis, slurry ice has proved to be a promising technology for damage inhibition and quality retention in a fatty fish species such as sardine. Ozonised slurry ice was also shown to be useful, since a longer shelf life was obtained in the present experiment and a pro‐oxidant effect of ozone on sardine lipids was not proved. 相似文献
54.
利用废铅酸蓄电池中的废硫酸作为浸取剂,对硼泥中的镁进行回收并制备出高品质的氢氧化镁产品。实验得出了酸浸硼泥的最佳工艺条件:酸浸温度为80℃;酸浸时间为30 min;酸用量为硫酸与硼泥质量比为1.2∶1。利用不同金属水解pH的不同,将酸浸过程中从硼泥和废硫酸中引入的杂质依次去除,得到精制硫酸镁溶液。由精制硫酸镁制取氢氧化镁的工艺条件为:常温下,沉淀剂为氨水,反应终点pH为11,反应时间为2 h,反应物在50℃下陈化12 h,过滤、洗涤后105℃烘干。实验考察了不同沉淀剂对氢氧化镁形貌的影响。所得氢氧化镁纯度在97%以上,粒径在0.1~1μm之间,各项指标均优于中国化工行业标准。 相似文献
55.
56.
Aeree Seo 《Electrochimica acta》2006,52(4):1603-1611
Carbon-supported Pt-based ternary alloy electrocatalysts were prepared by incipient wetness method in order to elucidate the origin of the enhanced activity of oxygen reduction reaction in PEMFC. To measure the catalytic activity and stability of the cathode alloy catalysts (electrodes containing Pt loading of 0.3 mg/cm2, 20 wt.% Pt/C, E-TEK), the I-V polarization curves were obtained. All alloy catalysts showed higher performances than Pt/C. It can be concluded that as platinum formed alloys with transition metals, the electronic state of Pt and the nearest neighbor Pt-Pt distance changes, which significantly influence the electrocatalytic activity for oxygen reduction.Long-term stability test was performed with the Pt6Co1Cr1/C alloy catalyst for 500 h. According to XPS analysis, the lower oxide component with Pt6Co1Cr1/C electrocatalyst provides a large portion of platinum in metallic species in the electrocatalyst and it seems to be mainly responsible for its enhanced activity towards oxygen reduction. 相似文献
57.
58.
料浆脱水是湿磨干烧的关键工艺,其脱水方法一般有过滤法,喷浆法和混合法三种,其中过滤法包括真空过滤和加压过滤两种,在国外都有应用,国内则大都用前者。南京院在皖维公司1000t/d生产线和白马山厂850t/d生产经上则采用了厢式压滤脱水法,文中就这两种过滤法的过滤工艺特点及其选择进行了分析和探讨。 相似文献
59.
研究我国大型优质神木煤田12个煤样的主要性质,对其水煤浆特性的影响。实验表明,煤中水分和含氧官能团是主要因素,水分中以最高内在水分与水煤浆浓度呈线性相关,提出以最高内在水分作为评价指标。并研究了煤浆的改性方法,一是加热方法使水分和官能团脱除,煤表面亲水性降低,使煤浆浓度大幅度提高,二是除去煤中可溶无机离子,可使煤浆粘度降低,并添加某些电解质有可能提高稳定性。 相似文献
60.
Environmental concerns have stimulated interest in utilizing plant-derived materials in various industrial fields. The main objective of the present study was to synthesize a new type of high-performance lignin series dispersant of coal–water slurry (CWS) from wheat straw alkali lignin (WAL), and determine the affecting factors in the reaction and the application performance for CWS preparation. The experimental results showed that the inherent viscosity and the sulfonic group content of the modified wheat straw alkali lignin (MSL) are the key factors affecting its dispersing effect for CWS. In the reaction, the reactant mass concentration and the sulfonating agent amount were changed to obtain the MSL with different inherent viscosities and sulfonic group contents, and the MSL with intermediate inherent viscosity (6.0 ml/g) and higher sulfonic group content (1.80 mmol g− 1) was found to have excellent dispersing effect for CWS. The MSL obtained from optimized process was used as dispersant for CWS preparation, the studies of the properties of CWS showed that MSL has similar dispersing effect with naphtalenesulfonate–formaldehyde condensate, and far better dispersing effect than lignosulphonate. Recently this kind of new dispersant has been applied in several power plants in China. 相似文献