Ag/MnO_2的制备及其对甲醛的催化降解

以高锰酸钾、双氧水和硝酸银为原料,采用化学沉淀法制备了Ag/MnO_2复合催化剂,利用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、比表面积(BET)和傅里叶变换红外光谱(FTIR)对Ag/MnO_2进行了表征。以Ag/MnO_2为催化剂,在室温、常压、无光照条件下对甲醛气体进行了催化降解实验。结果表明,Ag掺杂有效提高了MnO_2的催化活性和对甲醛的降解效果,3%-Ag/MnO_2 20 g对初始质量浓度为20 mg/m~3的甲醛催化降解4 h时,有效降解率达99.61%。     

双酚S型聚酰亚胺二胺单体的合成与表征

以对氯硝基苯和双酚S为原料经缩合和铁粉还原合成了聚酰亚胺二胺单体4,4’-双(4-氨基苯氧基)二苯基砜(P-BAPS);考查了工艺条件对产物收率的影响,并利用红外光谱(IR)、差式扫描量热仪(DSC)对其及聚合物进行表征.结果表明:当n(硝基物)∶n(铁粉)=1∶6.75,80℃下反应6h,产物收率可达87.70％;相...     

如何抓好项目成本管理

项目成本管理是对项目全过程、全方位、全员的管理,是一项综合性的管理工作。项目成本管理的优劣,直接影响着企业的总体效益和职工的切身利益。基于此,多方位,多层面地进行项目成本管理,狠抓成本控制,不断探索与总结有效降低项目成本的途径,保证产值的高利润率,对企业来说至关重要。     

臭氧/活性炭组合工艺降解甲基红印染废水的试验研究

文章采用臭氧/活性炭组合工艺对甲基红印染废水进行降解试验,考察了甲基红废水的pH、活性炭投加量、温度和臭氧流量等参数对印染废水色度和CODCr去除率的影响,确定了臭氧/活性炭组合工艺降解甲基红印染废水的最佳工艺条件。结果表明,在pH为3.5,温度为25℃,活性炭投加量为120 mg/L,臭氧流量为0.83 L/min,初始浓度为10 mg/L的条件下降解10 min,臭氧/活性炭组合工艺对甲基红废水的脱色率达到97.4%,CODCr去除率达到85.2%。该组合工艺能有效地去除印染废水的色度和CODCr,使出水水质达到处理标准。     

Fenton-铁氧体法处理含铜模拟废水的研究

采用Fenton-铁氧体法处理含铜模拟废水。在pH值3.0、温度40℃、反应时间10 min、H_2O_20.60mL/L、FeSO_4·7H_2O 7.08g/L的条件下,Cu~(2+)的去除率达到92.88%,残余Cu~(2+)的质量浓度为3.56 mg/L。铁氧体法的最优工艺条件为:沉淀pH值10.0,反应时间15 min,温度30℃,FeSO_4·7H_2O 0.154g/L,FeCl_3·6H_2O 0.225g/L。在Fenton-铁氧体法的优化条件下,Cu~(2+)的去除率达到98.28%,残余Cu~(2+)的质量浓度为0.86mg/L,达到排放标准。     

固定式推力滑动轴承失效分析及对策

对止推轴承磨损失效进行分析,并对轴承检修工艺提出瓦面修刮建议.     

无粘结预应力技术推广应用与技术创新

本文以江西省电网调度科研综合楼工程为例，重点介绍了无粘结预应力混凝土技术推广应用过程中采用的关键技术、技术创新。     

臭氧预氧化/混凝处理活性藏青废水的试验研究

文章采用臭氧预氧化与三氯化铁混凝联用工艺处理活性藏青印染废水,考察了臭氧流量、三氯化铁投加量、pH、废水温度等参数对活性藏青废水色度去除率和CODCr去除率的影响。结果表明在臭氧流量为40 L/h,通气时间为3 min,三氯化铁投加量为200 mg/L,pH为7,混凝温度为30℃的条件下,臭氧预氧化与三氯化铁混凝联用工艺对活性藏青废水有比较理想的降解效果,印染废水的色度去除率达到95.3%,CODCr去除率达到71.5%。     

Degradation of Acid Orange 7 Dye in Two Hybrid Plasma Discharge Reactors

To get an optimized pulsed electrical plasma discharge reactor and to increase the energy utilization efficiency in the removal of pollutants, two hybrid plasma discharge reactors were designed and optimized. The reactors were compared via the discharge characteristics, energy transfer efficiency, the yields of the active species and the energy utilization in dye wastewater degradation. The results showed that under the same AC input power, the characteristics of the discharge waveform of the point-to-plate reactor were better. Under the same AC input power, the two reactors both had almost the same peak voltage of 22 kV. The peak current of the point-to-plate reactor was 146 A, while that of the wire-to-cylinder reactor was only 48.8 A. The peak powers of the point-to-plate reactor and the wire-to-cylinder reactor were 1.38 MW and 1.01 MW, respectively. The energy per pulse of the point-to-plate reactor was 0.2221 J, which was about 29.4% higher than that of the wire-to-cylinder reactor （0.1716 J）. To remove 50% Acid Orange 7 （AO7）, the energy utilizations of the point-to-plate reactor and the wire- to-cylinder reactor were 1.02×10^-9 mol/L and 0.61×10^-9 mol/L, respectively. In the point-to- plate reactor, the concentration of hydrogen peroxide in pure water was 3.6 mmol/L after 40 min of discharge, which was higher than that of the wire-to-cylinder reactor （2.5 mmol/L）. The concentration of liquid phase ozone in the point-to-plate reactor （5.7×10^-2 mmol/L） was about 26.7% higher than that in the wire-to-cylinder reactor （4.5×10^-2 mmol/L）. The analysis results of the variance showed that the type of reactor and reaction time had significant impacts on the yields of the hydrogen peroxide and ozone. The main degradation intermediates of AO7 identified by gas chromatography and mass spectrometry （GCMS） were acetic acid, maleic anhydride, p- benzoquinone, phenol, benzoic acid, phthalic anhydride, coumarin and 2-naphthol. Proposed degradation pathways were elucidated in light of the ana     

超声波-铁氧体法处理含镍模拟电镀废水的研究

采用超声波-铁氧体法对含镍模拟电镀废水进行处理,考察了pH值、超声波辐射时间、声能密度、H2O2的投加量、加料摩尔比(nFe2+∶nNi2+)、Ni2+的初始质量浓度以及不同金属离子共存对废水中Ni2+的去除率的影响.结果表明:在H2O2的投加量为28.4 mg/L,加料摩尔比为2,pH值为11.5,温度为50℃,反应时间为45 min的条件下,废水中Ni2+的质量浓度从250 mg/L降至0.495 mg/L,去除率达到99.40％,达到国家排放标准.