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131.
Resin adsorption technique with XAD-8 and XAD-4 was used to characterize the raw water from Erlong reservoir in Jilin province of China. The NOM chemical composition sequences of four organic fractions in the raw water,from high to low,are fulvic acid (FA) fraction,hydrophilic non-acid (HPINA) fraction,hydrophilic acid (HPIA) fraction,and humic acid (HA) fraction. Experimental results show that FA is the main precursor of THMFP among the four organic fractions. However,HA or hydrophobic acid exhibits the highest chlorination activity in forming THMs. It is also found that the value of FI/DOC or SUVA and the specific THMFP have better positive correlation. It is implied that certain source water has unique nature of NOM and DBPs. 相似文献
132.
Preparation and electrochemical characterization of activated carbons by chemical-physical activation 总被引:2,自引:0,他引:2
A process was proposed based on the combination of chemical and physical activation for the production of activated carbons
used as the electrode material for electric double layer capacitor (EDLC). By material characterization and electrochemical
methods, the influences of the activitation process on the specific surface area, pore structure and electrochemical properties
of the activated carbons were investigated. The results show that specific surface area, the mesopore volume, and the specific
capacitance increase with the increase of the mass ratio of KOH to char (m(KOH)/m(char)) and the activation time, respectively. When m(KOH)/m(char) is 4.0, the specific surface area and the mesopore volume reach the maximum values, i.e. 1 960 m2/g and 0.308 4 cm3/g, and the specific capacitance is 120.7 F/g synchronously. Compared with the chemical activation, the activated carbons
prepared by chemical-physical activation show a larger mesopore volume, a higher ratio of mesopore and a larger specific capacitance.
Foundation item: Project(2007BAE12B01) supported by the National Key Technology Research and Development Program of China 相似文献
133.
Model test of the cutting properties of a shearer drum 总被引:1,自引:1,他引:0
According to similarity theory, we carded out a dimensional analysis of the shearer drum correlation parameters and built similarity criteria. Based on these, similarity models of shearer drums were developed. Simultaneously, based on an estab-lished cutting testbed of the coal and rock, cutting tests of different pick arrangements of the drum models were carried out, where the compressive strength of the analogous cutting material was 2.48 MPa and the drum rotary speed 67.5 r/min. The variance, the mean values, maxima and mean maxima of the torque load were analyzed for different type drum models. Moreover, the relation-ships between the type of pick arrangements and the cutting lump coal percentage were studied. The results indicate that the load fluctuation of the sequence drum is larger than that of the punnett square drum in the cutting process and the lump coal percentage and economic benefits of the sequence drum are inferior to the punnett square drum. We conclude that the punnett square drum is superior to the sequence drum. 相似文献
134.
Non-liner wave equation inversion, wavelet analysis and artificial neural networks were used to obtain stratum parame-ters and the distribution of thin coal seams. The lithology of the water-bearing/resisting layer in the Quaternary system was also predicted. The implementation process included calculating the well log parameters, stratum contrasting the seismic data and the well logs, and extracting, studying and predicting seismic attributes. Seismic inversion parameters, including the layer velocity and wave impedance, were calculated and effectively used for prediction and analysis. Prior knowledge and seismic interpretation were used to remedy a dearth of seismic data during the inversion procedure. This enhanced the stability of the inversion method. Non-linear seismic inversion and artificial neural networks were used to interpret coal seismic lithology and to study the wa-ter-bearing/resisting layer in the Quaternary system. Interpretation of the 1-2 m thin coal seams, and also of the wa-ter-bearing/resisting layer in the Quaternary system, is provided. The upper mining limit can be lifted from 60 m to 45 m. The pre-dictions show that this method can provide reliable data useful for thin coal seam exploitation and for lifting the upper mining limit, which is one of the principles of green mining. 相似文献
135.
136.
在线性红利下将保单到达过程推广为Poisson过程,并通过添加Brownian运动来刻画保险公司不确定的收益和付款,建立线性红利下带干扰的复合Poisson风险模型.运用鞅方法得出了破产概率满足的Lundberg不等式和一般公式,并给出了生存概率满足的积分—微分方程。 相似文献
137.
应用基于TRIZ理论的产品技术成熟度预测技术和基于该技术开发的产品技术成熟度预测软件TMMS对我国并联机构技术成熟度进行了预测,得出其尚处于婴儿期前期,产品市场化的条件还不成熟,企业对该技术的投入较大,以进行型综合、解耦等方面研究的预测结果. 相似文献
138.
结合印刷专业的特点,提出了印刷原理与工艺课程教学改革的几点建议:转变教育理念、革新教学内容、改进课堂教学方法及改革实践教学。这些教学改革与实践将对印刷专业的发展起到一定的推动作用。 相似文献
139.
采用等体积浸渍法制备了Ni/γ-Al2O3和Ni/La2O3-γ-Al2O3系列催化剂,通过固定床反应、热重分析等方法,考察了催化剂的性能。结果表明:Ni质量分数为10%的Ni/γ-Al2O3催化剂具有较高的活性;稀土元素La的加入,提高了催化剂的抗积炭性能;在相同的反应条件下,10%Ni/3%La2O3-γ-Al2O3催化剂的积炭量比10%Ni/γ-Al2O3催化剂积炭量降低了40%,稳定性大大提高。以Ni/La2O3-γ-Al2O3催化剂中Ni质量分数10%,并且La质量分数3%为最佳,实验条件下制得的合成气CO/H2接近1/1。 相似文献
140.
在Hilbert框架下借助于度量投影修正Mann迭代程序,证明了关于无限族非扩张映射的强收敛定理,并用于求解分裂可行性问题SFP.研究成果在很大程度上推广和改进了现有的结果. 相似文献