Uptake and concentration of heavy metals in dominant mangrove species from Hainan Island,South China

Environmental Geochemistry and Health - By investigating three dominant mangrove species, namely Aegiceras corniculatum, Kandelia candel, Ceriops tagal and their rhizosediment in Mangrove wetlands...     

Research progress and hot spots of hydrothermal liquefaction for bio-oil production based on bibliometric analysis

Environmental Science and Pollution Research - Hydrothermal liquefaction (HTL) of biomass used HTL reaction under high temperature and pressure to produce bio-oil. This technology is considered as...     

Comparison on surface properties and desulfurization of MnO2 and pyrolusite blended activated carbon by steam activation

In this study, MnO₂ and pyrolusite were used as the catalysts to prepare modified activated carbon, that is, AC-Mn and AC-P, respectively, from coals by blending method and steam activation. The Brunauer–Emmett–Teller (BET) results indicated that the AC-P had higher surface areas and micropore volumes than the AC-Mn with the same blending ratio. The relative contents of basic functional groups (i.e., C = O, π-π*) on AC-P were slightly lower than those on AC-Mn, while both contained the same main metal species, namely, MnO. The desulfurization results showed that with 3 wt% of blending ratio, AC-Mn3 and AC-P3 had higher sulfur capacities at 220 and 205 mg/g, respectively, which were much higher than for the blank one (149.6 mg/g). Moreover, the AC-P had relatively higher sulfur capacity than the AC-Mn with the same contents of Mn, which might be attributed to the existence of other metals in pyrolusite. After the desulfurization process, MnO were gradually transferred into MnSO₄, and the relative contents of basic functional groups decreased evidently for both AC-Mn3 and AC-P3. The results demonstrated that pyrolusite could be one good alternative to MnO₂ to prepare modified activated carbon for desulfurization.

Implications: MnO₂ and pyrolusite were used as the additives to prepare modified activated carbon from coals by a blending method and by steam activation, that is, AC-Mn and AC-P, respectively. The AC-P had higher surface areas and micropore volumes than the AC-Mn with the same blending ratio. The AC-Mn and AC-P had higher sulfur capacities than a blank one. Moreover, the AC-P had relatively higher sulfur capacity than the AC-Mn with the same contents of Mn. The results demonstrated that pyrolusite could be one good alternative to MnO₂ to prepare modified activated carbon for desulfurizatio.     

警用头盔的人机工程学分析

警用头盔是武警部队使用最为频繁的单兵防护用具，本文基于人机工程学的理论，用人机工程学的观点对武警部队现装备的警用头盔进行分析和探讨，提出解决途径的设想，展望警用头盔的发展前景。     

序批式反应器生物强化处理苯酚废水的研究

将4株高效苯酚分解菌湿菌体分3批投加于序批式反应器(SBR),对活性污泥进行生物强化试验,分析活性污泥状态与性能变化,测定生物强化后对苯酚的降解能力.结果表明,随着生物强化过程的进行,沉降性能改善,污泥颗粒化趋势明显;生物强化后,活性污泥对苯酚降解能力、降解速率及对苯酚的耐受性明显提高:苯酚质量浓度为730～960mg/L时,苯酚完全降解时间可由正常的6h缩短至2h;6h内可完全降解苯酚的质量浓度由原来的880mg/L提高到2080mg/L,处理能力提高了1.36倍;当进水苯酚质量浓度增加到2400mg/L时,6h内污泥对苯酚的降解率仍达到60.1%.     

压力板仪法测土-水特征曲线试验研究

非饱和土土-水特征曲线(SWCC)表示了土中含水量与吸力之间的关系。针对非饱和土干-湿循环过程中的吸力变化特征,开展试验研究。采用体积压力板仪实现非饱和土的脱湿和吸湿过程。试验成果显示:(1)土-水特征曲线是不稳定的,它与土体含水率的变化路径有关;(2)在干湿循环过程中,相同的基质吸力具有不同的含水量。     

优势菌的筛选及其强化活性污泥好氧反硝化的研究

利用含活性污泥提取物的贫培养基筛选SBR系统中的好氧异养优势菌。结合自然温度（15～20℃）、延长培养时间等条件来提高菌群的可培养性。从SBR活性污泥系统中分离出5种细菌。4株去除COD优势菌，1株异养硝化细菌，能在好氧条件下实现对总氮的去除。反应池底采用边缘对称曝气，反应池内细菌在时间顺序和空间位置上循环经历好氧过程及微氧过程。将PVA铝盐法固定的细菌对反应器进行生物强化。结果显示，在好氧工艺的条件下，投加优势菌群后，与未加优势菌群的反应器相比，可以显著改善污泥的沉降性能，COD、NH₃-N和TN降解率显著提高，分别达到98%、97%和90%。生物强化作用明显，反应器内具有良好的好氧反硝化环境。     

Modification of ferrite–manganese oxide sorbent by doping with cerium oxide

Fe–Mn oxide and Ce-doped Fe–Mn oxide sorbents were studied on the structural and desulfurization behavior in COS removal from syngas. The effects of cerium oxide on the Fe–Mn oxides have been investigated by XRD, BET, TPR, XPS and TEM methods. Analysis data show that the Ce-doped sorbent has larger specific surface area and better particles’ dispersion compared with non-modified Fe–Mn sorbent. The addition of Ce improves the reduction performance of Fe–Mn species. The desulfurization experiments show that the desulfurization activity of sorbent can be increased because of the promotion of the structural and redox properties by ceria doped. The Ce-doped sorbent can reduce COS from 15,000 ppmv to less than 0.1 ppmv at 325 °C and a space velocity of 1000 h⁻¹.     

胺丙基硅的微结构和表面特性在其对两种微囊藻毒素吸附中的作用

考察了粒状胺丙基硅(CUNAX00X)对水溶液中微囊藻毒素-LR(mLR)和微囊藻毒素-LA(mLA)的等温吸附行为,并通过对胺丙基硅结构中的微孔尺寸分布特征、表面官能团--胺丙基团(-CH2CH2CH2NH 3)和羟基自由基(·OH)的红外分析,对吸附机制进行了初步探讨.结果表明,胺丙基硅通过物理吸附和化学吸附对水溶液中的mLR和mLA进行吸附,即胺丙基硅结构中的有效吸附微孔对mLR/mLA的物理吸附,固体表面离子化的胺丙基团和·OH与mLR/mLA分子结构中离子化的羧基(-COO-)以及pH=4.33条件下mLR分子结构中离子化的胍基(-NHCNH·NH 2)之间的弱离子吸附.     

污泥加热预处理对中温厌氧消化的影响

对污泥加热预处理给中温厌氧混合消化和污泥单独消化带来的影响进行了研究.研究结果表明,污泥加热预处理有利于提高混合消化对 COD 的去除率,尤其是 SCOD 的去除率由 77%增长到 93%,但不利于 TS 和 VS 的去除;而对污泥单独消化,预处理则不利于有机物的去除.采用加热预处理后的污泥进样,混合消化和污泥单独消化的甲烷产气量均有所提高.