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121.
本文论述了中国水利水电工程开发与区域可持续发展的关系,并提出了中国实现可持续的水利水电工程开发的主要对策。 相似文献
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Watering techniques and zero-valent iron biochar pH effects on As and Cd concentrations in rice rhizosphere soils, tissues and yield 总被引:1,自引:0,他引:1
Md Shafiqul Islam Yali Chen Liping Weng Jie M Zulqarnain Haider Khan Zhongbin Liao Abdoul Salam Issiaka Abdoul Magi Yongtao Li 《环境科学学报(英文版)》2021,33(2):144-157
Zero-valent iron amended biochar (ZVIB) has been proposed as a promising material in immobilizing heavy metals in paddy fields. In this study, the impacts of pH of ZVIB (pH 6.3 and pH 9.7) and watering management techniques (watering amount in the order of CON (control, 5/72)>3/72>1–3/72>3/100>1/72, with 5/72, for example, representing irrigation given to 5 cm above soil surface in 72 hr regular interval) on As and Cd bioavailability for rice and its grain yield (YieldBR) were investigated in a pot experiment. Brown rice As (AsBR) content was irrelative to the watering treatments, while significantly decreased (>50%) with the addition of both ZVIB materials. The diminutions of brown rice Cd (CdBR) content as well as the YieldBR were highly dependent on both the soil amendment materials’ pH and watering amount. Among all the watering treatments, 3/72 treatment (15% less irrigation water than the CON) with ZVIB 6.3 amendment was the optimum fit for simultaneous reduction of AsBR (50%) and CdBR contents (19%) as well as for significant increment (12%) of the YieldBR. Although high pH (9.7) ZVIB application could also efficiently decrease As and Cd contents in brown rice, it might risk grain yield lost if appropriate (e.g. 3/72 in our study) watering management technique was not chosen. Therefore, ZVIB would be an environmentally friendly option as an amendment material with proper selection of watering management technique to utilize As and Cd co-contaminated arable soils safely for paddy cultivation. 相似文献
125.
Selective catalytic reduction(SCR) with urea catalyzed by Cu-SAPO-34 is an effective method to eliminate NO_x from diesel exhaust. However, urea-related deposits may form during cold-start and urban driving due to low exhaust temperatures. The activity of CuSAPO-34 at 175°C is significantly degraded by urea exposure, and 300°C is required for regeneration. Through in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) and temperature-programmed hydrolysis studies, the dominant stable deposit at 175°C is identified as biuret, which can be eliminated at 300°C. The urea-derived deactivation and regeneration mechanisms of Cu-SAPO-34 were compared with those of anatase-supported catalysts. 相似文献
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The catalytic activity and durability of Rh/ZrO_2 catalyst were investigated compared with Rh/Al_2O_3 catalyst under diverse aging atmospheres, including lean, rich and lean–rich cyclic aging atmospheres, to simulate the real working conditions of three-way catalyst.Oxidation states and microstructures of rhodium species were investigated to correlate with the catalytic performance of the catalysts. The catalytic performance and durability of the Rh catalyst under diverse aging atmospheres were drastically enhanced by ZrO_2 support. ZrO_2 support was confirmed to be able to effectively inhibit rhodium sintering even under diverse aging conditions. It can also successfully keep Rh species in an active low-valence state on the surface of the catalyst. The superiority of ZrO_2 support compared to Al_2O_3 was verified by the Rh-based monolith catalyst. 相似文献
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Nathan Dunkin ShihChi Weng Joseph G. Jacangelo Kellogg J. Schwab 《Food and environmental virology》2017,9(4):473-486
One key assumption impacting data quality in viral inactivation studies is that reduction estimates are not altered by the virus seeding process. However, seeding viruses often involves the inadvertent addition of co-constituents such as cell culture components or additives used during preparation steps which can impact viral reduction estimates by inducing non-representative oxidant demand in disinfection studies and fouling in membrane assessments. The objective of this study was therefore to characterize a mammalian norovirus surrogate, murine norovirus (MNV), and bacteriophage MS2 at sequential stages of viral purification and to quantify their potential contribution to artificial oxidant demand and non-representative membrane fouling. Our results demonstrate that seeding solvent extracted and 0.1 micron filtered MNV to ~105 PFU/mL in an experimental water matrix will result in additional total organic carbon (TOC) and 30 min chlorine demand of 39.2 mg/L and 53.5 mg/L as Cl2, respectively. Performing sucrose cushion purification on the MNV stock prior to seeding reduces the impacts of TOC and chlorine demand to 1.6 and 0.15 mg/L as Cl2, respectively. The findings for MNV are likely relevant for other mammalian viruses propagated in serum-based media. Thus, advanced purification of mammalian virus stocks by sucrose cushion purification (or equivalent density-based separation approach) is warranted prior to seeding in water treatment assessments. Studies employing bacteriophage MS2 as a surrogate virus may not need virus purification, since seeding MS2 at a concentration of ~106 PFU/mL will introduce only ~1 mg/L of TOC and ~1 mg/L as Cl2 of chlorine demand to experimental water matrices. 相似文献
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Metal contamination in sediments of the western Bohai Bay and adjacent estuaries, China 总被引:5,自引:0,他引:5
Feng H Jiang H Gao W Weinstein MP Zhang Q Zhang W Yu L Yuan D Tao J 《Journal of environmental management》2011,92(4):1185-1197
Twelve sediment cores were collected in July 2007 in open waters of western Bohai Bay, the Port of Tianjin, and the adjacent estuaries of the Haihe and Yongding Rivers. While overall concentrations of trace metals at incremental depths in these cores met the Marine Sediment Quality (GB18668-2002) criteria of China, the magnitude of both metal enrichment factors (EF) and geoaccumulation indices (I(geo)) suggested that pollution with Ag, Cd, Cr, Cu and Zn was occurring in the estuaries and Port. Risk analysis also suggested that Ag and Ni concentrations were sufficiently elevated as to cause adverse biological effects in the study area. Although metal concentrations in western Bohai Bay were of less concern, a positive relationship between EF values and excess (210)Pb activity for several metals suggested that their concentrations were increasing over time. 相似文献
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Chi-Yuan Lee Fang-Bor Weng Ten-Lom Chen Fan-Hsuan Liu 《International Journal of Green Energy》2016,13(6):624-629
This study developed an integrated (flow, voltage, and temperature) micro sensor using the micro-electro-mechanical systems (MEMS) technology. It was inserted into the high temperature proton exchange membrane fuel cell (HT-PEMFC) for local real-time measurement. The integrated micro sensor is made of 40 µm thick stainless steel base material, and its protective layer is formed by polyimide (PI) that has better temperature resistance. The integrated micro sensor has three functions, and is favorably characterized by small size, good acid resistance and temperature resistance, quick response, real-time measurement, and being able to be put in any place for measurement. After calibration, and its reliability confirmed, the integrated micro sensor is inserted into the HT-PEMFC for local microcosmic measurement. 相似文献