Intervention of pentoxifylline on silica-induced inflammatory reaction and apoptosis

Pentoxifylline (PTX) is a clinically used drug mainly for peripheral circulation improvement. This drug also possesses potent anti-inflammatory effects and was found to inhibit acute lung injury induced by chemical agents in animal models. Since it is also a potential apoptosis enhancer, this study was designed to examine the influence of PTX on silica-induced lung inflammation and pulmonary leucocyte apoptosis. Male Wistar rats were intratracheally instilled with either silica dust suspension or saline and intraperitoneally injected with saline or PTX. These treatments continued for six weeks and all rats were then sacrificed to obtain bronchoalveolar lavage cells and lavage fluid. Data demonstrated that PTX attenuated silica-induced lung injury in the rat model and this attenuation may possibly be attributed to its role in the enhancement of pulmonary apoptosis. As a known clinically safe drug, PTX may thus have potential use in the treatment of human silicosis.     

Effects of Watershed Impervious Cover on Dissolved Silica Loading in Storm Flow1

Abstract: Dissolved silica (DSi) availability is a factor that affects the composition of algal populations in aquatic ecosystems. DSi cycling is tightly linked to the hydrological cycle, which is affected by human alterations of the landscape. Development activities that increase impervious cover change watershed hydrology and may increase the discharge of DSi‐poor rainwater and decrease the discharge of DSi‐rich ground water into aquatic ecosystems, possibly shifting algal community composition toward less desirable assemblages. In this study, DSi loadings from two adjacent coastal watersheds with different percent impervious cover were compared during four rain and five nonrain events. Loadings in the more impervious watershed contained a significantly larger proportion of surface runoff than base flow (ground‐water discharge) and had lower [DSi] water during rain events than the less impervious watershed. Application of the Soil Conservation Service Curve Number (CN) method showed that the minimum rainfall height necessary to yield runoff was significantly lower for the more impervious watershed, implying that runoff volumes increase with impervious cover as well as the frequency of runoff‐yielding events. Empirical data collected during this study and estimates derived from the CN method suggest that impervious cover may be responsible for both short‐term DSi limitation during rain events as well as long‐term reduction of DSi inputs into aquatic ecosystems.     

铅离子印迹电化学传感器的制备及检测性能研究

重金属因其具有高毒性、致癌性和潜在的生物积累性，引发的环境问题受到广泛关注。为精确监测环境中的重金属污染，结合电化学分析和离子印迹技术的优势，构筑了对铅离子的高灵敏电化学传感器。利用铅离子作为模板，采用3-（γ-氨基乙氨基）-丙基-三甲基硅烷作为功能单体，在介孔硅表面，通过共缩聚法制备了离子印迹聚合物，并将其作为电化学传感器的核心识别元件。经过优化碳糊电极的组成，制备了一系列高选择性的离子印迹电化学传感器，并对其电化学行为进行了分析。测试结果表明，所制传感器对铅离子的检测线性范围为10^-9～10^-6 mol/L，且检出限达到1.3×10^-11mol/L（信噪比=3）。在对河水和大米等实际样品的检测中，传感器展现了高灵敏性（相对标准偏差为2.5%～7.4%）和高准确性（回收率为98.8%～102.9%），表明其在环境监测和食品安全检测方面具有应用潜力。     

胶体灭火剂试验研究

分析了用水灭火时存在的明显不足，引入了可改善水灭火性能，提高水灭火安全性和灭火效率的胶体灭火剂。对作为实验用火源的木垛尺寸，水和胶体的实验流量进行了理论分析和设计，设计和制造了可实现定量配比胶体火火剂的试验装置。利用自行设计的灭火实验装置，研究了胶体灭火剂和水对比的流动性能，抗燃性能和灭火性能。实验结果显示，胶体灭火剂在一定浓度范围内具有较好的流动性，不会提高胶体在管路中的流动阻力；与水相比，胶体灭火剂具有优异的抗燃和灭火效果。     

扬州电厂200MW机组烟气脱硫石灰石制粉系统

介绍了扬州电厂石灰石制粉系统、主要设计参数及其核心设备的技术特点，为同类工程提供参考。     

废弃饱和盐水钻井液的固液分离

采用化学破胶脱稳和压滤机械分离的化学强化固液分离技术处理江汉油田废弃饱和盐水钻井液(简称废钻井液).最佳固液分离工艺为:调节废钻井液的pH为6.5左右,先加入无机破胶剂(HWJ),HWJ的加入量为15 000 mg/L,以400 r/min的转速搅拌3 min,稀释1倍后,再加入有机破胶剂(HYJ),HYJ的加入量为300 mg/L,以120 r/min的转速搅拌5min.固液分离结果表明,分离后出水率达68.2%,而泥饼湿含量只有55.8%,废钻井液的COD由67 886.8 mg/L降至8 898.9 mg/L.     

沈抚灌渠污水预处理实验研究

以砾石为填料采用生物滤池法和以纤维束为填料采用生物接触氧化法,分别预处理沈抚灌渠污水。试验结果表明,在水力停留时间在3．5h,控制气水比分别为5：1和4：1的反应条件下,砾石填料对COD和NH3-N的平均去除率分别为53．9％和53．6％;纤维束软填料对COD和NH3-N的平均去除率分别为55．7％和47．7％。前者对COD和NH3-N的处理效果都达到了预定要求,而后者对NH3-N的处理效果没有达到要求。     

微污染水源水的控制技术

饮用水水源的污染日益严重,对人类的健康和传统净水工艺都构成了较大的威胁,更加剧了水资源的危机,文中阐述了近年来我国处理微污染水源水的主要技术,强化混凝处理技术,臭氧活性炭联用深度处理技术,生物活性炭深度处理技术,光催化氧化法技术,膜法深度处理技术,吸附预处理技术,生物预处理技术等,并给出了各种处理方法的优缺点。     

Chemically modified silica gel with 1-{4-[(2-hydroxy-benzylidene)amino]phenyl}ethanone: Synthesis, characterization and application as an efficient and reusable solid phase extractant for selective removal of Zn(II) from mycorrhizal treated fly-ash samples

1-{4-[(2-hydroxy-benzylidene)amino]phenyl}ethanone functionalized silica gel was synthesized and used as a highly efficient, selective and reusable solid phase extractant for separation and preconcentration of trace amount of Zn(II) from environmental matrices. The adsorbent was characterized by fourier transform infrared spectroscopy (FT-IR), elemental analysis,¹³C CPMAS NMR spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and BET surface area analysis. The dependence of zinc extraction on various analytical parameters such as pH, type and amount of eluent, sample flow rate and interfering ions were investigated in detail. The material exhibited superior adsorption efficiency for Zn(II) with high metal loading capacity of 1.0 mmol/g under optimum conditions. After adsorption, the recovery (> 98%) of metal ions was accomplished using 1.0 mol/L HNO₃ as an eluent. The sorbent was also regenerated by microwave treatment in milder acidic environment (0.1 mol/L HNO₃). The lower detection limit and preconcentration factor of the present method were found out to be 0.04 μg/L and 312.5 respectively. The modified silica surface possessed excellent selectivity for the target analytes and the adsorption/desorption process remained effective for at least ten consecutive cycles. The optimized procedure was successfully implemented for the extraction of Zn(II) from mycorrhizal treated fly ash and pharmaceutical samples with reproducible results.     

Response of anaerobes to methyl fluoride, 2-bromoethanesulfonate and hydrogen during acetate degradation

To use the selective inhibition method for quantitative analysis of acetate metabolism in methanogenic systems,the responses of microbial communities and metabolic activities,which were involved in anaerobic degradation of acetate,to the addition of methyl fluoride(CH3F),2-bromoethanesulfonate(BES)and hydrogen were investigated in a thermophilic batch experiment.Both the methanogenic inhibitors,i.e.,CH3F and BES,showed their effectiveness on inhibiting CH4 production,whereas acetate metabolism other than acetoclastic methanogenesis was stimulated by BES,as reflected by the fluctuated acetate concentration.Syntrophic acetate oxidation was thermodynamically blocked by hydrogen(H2),while H2-utilizing reactions as hydrogenotrophic methanogenesis and homoacetogenesis were correspondingly promoted.Results of PCR-DGGE fingerprinting showed that,CH3F did not influence the microbial populations significantly.However,the BES and hydrogen notably altered the bacterial community structures and increased the diversity.BES gradually changed the methanogenic community structure by affecting the existence of different populations to different levels,whilst H2 greatly changed the abundance of different methanogenic populations,and induced growth of new species.