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821.
This meta‐analysis investigates the direction and strength of the relationship between diversity in culturally diverse teams and team creativity/innovation. We distinguish the effects of two diversity levels (i.e., surface level vs. deep level) in culturally diverse teams and examine the moderators suggested by the socio‐technical systems framework (i.e., team virtuality and task characteristics in terms of task interdependence, complexity, and intellectiveness). Surface‐level diversity in culturally diverse teams is not related to team creativity/innovation, whereas deep‐level diversity in culturally diverse teams is positively related to team creativity/innovation. Moreover, surface‐level diversity in culturally diverse teams and team creativity/innovation are negatively related for simple tasks but unrelated for complex tasks. Deep‐level diversity in culturally diverse teams and team creativity/innovation is positively related for collocated teams and interdependent tasks but unrelated for noncollocated teams and independent tasks. We discuss the theoretical and practical implications. 相似文献
822.
823.
利用大庆油田特殊的地质构造,将氰化物浓度0.05mg/L的含氰废水注入油田边水构造。通过储层砂体吸附和渗透率损害实验,证明储层对氰化物有吸附作用,不同平衡浓度下砂体的静态吸附量为4.88μg/g,动态吸附量为2.837μg/g,氰化物不堵塞地层,根据注入井与注入井、注入井与采油井之间距离的不同,共布设8种注入方案。设计注入井的注入量为210m3/d,采油井的产液量为105m3/d,以采油井采出氰化物浓度0.05mg/L为限定值,基于动态吸附实验结果和边水对氰化物的稀释作用,应用聚合物驱油模型计算最佳的注入方案,该方案为注入井之间的间距1.0km,注入井与采油井之间的间距为2.5km,注入年限为54年。研究结果表明,在大庆油田实施含氰废水的深井注入是可行的。既达到处理含氰废水的目的,又利用含氰废水驱替原油,具有实用价值和推广作用。 相似文献
824.
825.
北京地铁义和庄站基坑支护结构及变形监测 总被引:3,自引:2,他引:1
结合北京地铁义和庄站深基坑支护变形监测方案,并通过大量实测数据对基坑的水平变形、钢支撑和锚索拉力变化规律进行了研究;并比较排桩、内支撑与排桩、锚索两种支护形式的变形差异.监测结果表明:围护结构的变形增量主要发生在基坑深层土体开挖及支撑结构架设前后阶段,在开挖至坑底后变形趋于稳定;支撑内力增加影响因素较多,包括地面堆载及温度影响;围护结构变形与支撑轴力变化具有显著的关联性;桩撑与桩锚支护结构的变形具有一定的差异性. 相似文献
826.
To understand the compositions and structures of microbial communities in different acid-aqueous environments, a PCR-based cloning approach was used. A total of five samples were collected from two mines in China. Two samples, named as G1 and G2, were acid mine drainage (AMD) samples and from Yunfu sulfide mine in Guangdong province, China. The rest of the three samples named as D1, DY and D3, were from three sites undertaking bioleaching in Yinshan lead-zinc mine in Jiangxi province, China. Phylogenetic analysis revealed that bacteria in the five samples fell into six putative divisions, which were α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Firmicutes, Actinobacteria and Nitrospira. Archaea was only detected in the three samples from Yinshan lead-zinc mine, which fell into two phylogenentic divisions, Thermoplsma and Ferroplasma. In addition, the results of principal component analysis (PCA) suggested that more similar the geochemical properties in samples were, more similar microbial community structures in samples were. 相似文献
827.
Batch experiments were carried out to investigate the influences of H2O2/Fe(II) molar ratio, pH, sequence of pH adjustment, initial As(V) concentration, and interfering ions on As(V) removal in H2O2-Fe(II) process from synthetic acid mine drainage (AMD). The optimum H2O2/Fe(II) molar ratio was one for arsenate removal over the pH range of 4-7. Arsenate removal at pH 3 was poor even at high Fe(II) dosage due to the high solubility of Fe(III) formed in situ. With the increase of Fe(II) dosage, arsenate removal increased progressively before a plateau was reached at pH 5 as arsenate concentration varied from 0.05 to 2.0 mg L−1. However, arsenate removal was negligible at Fe/As molar ratio <3 and then experienced a striking increase before a plateau was reached at pH 7 and arsenate concentration ≥1.0 mg L−1. The co-occurring ions exerted no significant effect on arsenate removal at pH 5. The experimental results with synthetic AMD revealed that this method is highly selective for arsenate removal and the co-occurring ions either improved arsenate removal or slightly depressed arsenate removal at pH 5-7. The extended X-ray absorption fine structure (EXAFS) derived As-Fe length, 3.27-3.30 Å, indicated that arsenate was removed by forming bidentate-binuclear complexes with FeO(OH) octahydra. The economic analysis revealed that the cost of the H2O2-Fe(II) process was only 17-32% of that of conventional Fe(III) coagulation process to achieve arsenate concentration below 10 μg L−1 in treated solution. The results suggested that the H2O2-Fe(II) process is an efficient, economical, selective and practical method for arsenate removal from AMD. 相似文献
828.
A range of macroinvertebrate indices were compared to assess the most appropriate metric for the assessment of acid mine drainage (AMD) in a low alkalinity, highly erosional river in south-east Ireland. Differences were found in the ability of indices to discriminate AMD impact with the Brillouin, BMWP score, Margalef and Shannon Indices the most precise. Taxon richness was also strongly correlated with AMD indicator parameters (e.g. pH alkalinity, sulphate, Zn and Fe) at impacted sites being an equally reliable metric. The response of the community structure to AMD in this river does not fulfil the optimum criteria for either diversity or biological indices, which may explain the variation in the success of different indices seen in this and other studies. The development of indices that model the expected community response to AMD more accurately or are based on the response of indicator species to AMD pollutants are required. 相似文献
829.
Simulation of Daily Flow Pathways,Tile‐Drain Nitrate Concentrations,and Soil‐Nitrogen Dynamics Using SWAT 下载免费PDF全文
Charles D. Ikenberry Michelle L. Soupir Matthew J. Helmers William G. Crumpton Jeffrey G. Arnold Philip W. Gassman 《Journal of the American Water Resources Association》2017,53(6):1251-1266
Tile drainage significantly alters flow and nutrient pathways and reliable simulation at this scale is needed for effective planning of nutrient reduction strategies. The Soil and Water Assessment Tool (SWAT) has been widely utilized for prediction of flow and nutrient loads, but few applications have evaluated the model's ability to simulate pathway‐specific flow components or nitrate‐nitrogen (NO3‐N) concentrations in tile‐drained watersheds at the daily time step. The objectives of this study were to develop and calibrate SWAT models for small, tile‐drained watersheds, evaluate model performance for simulation of flow components and NO3‐N concentration at daily intervals, and evaluate simulated soil‐nitrogen dynamics. Model evaluation revealed that it is possible to meet accepted performance criteria for simulation of monthly total flow, subsurface flow (SSF), and NO3‐N loads while obtaining daily surface runoff (SURQ), SSF, and NO3‐N concentrations that are not satisfactory. This limits model utility for simulating best management practices (BMPs) and compliance with water quality standards. Although SWAT simulates the soil N‐cycle and most predicted fluxes were within ranges reported in agronomic studies, improvements to algorithms for soil‐N processes are needed. Variability in N fluxes is extreme and better parameterization and constraint, through use of more detailed agronomic data, would also improve NO3‐N simulation in SWAT. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series. 相似文献
830.
基于柴油机实验台架和颗粒捕集装置,采用聚苯硫醚(PPS)针刺毡滤布过滤柴油机排放的颗粒物(PM)。利用称重法,以Whatman玻璃纤维滤纸为对比滤纸,间接测试了3种PPS滤布的过滤效率;同时实验探索了表面涂覆聚四氟乙烯的PPS滤布的深床过滤时间。实验结果表明,3种滤布在180℃的加热条件下将出现颜色和形态的变化;3种滤布在深床过滤期对PM的平均过滤效率分别为78.8%、76.9%和83.7%;表面涂覆聚四氟乙烯的PPS滤布的深床过滤时间为15~20 min,此后其过滤效率可接近100%。 相似文献