充分发挥市场经济优势搞好国家重点环保实用技术的推广工作

文章主要阐述了在社会主义市场经济体制条件下如何搞好环保实用技术的推广工作。     

Cash-based interventions: lessons from southern Somalia

Commodity distributions, the predominant relief response, are subject to growing criticism, while donors and humanitarian actors are increasingly viewing cash-based interventions as a viable alternative. This paper aims to contribute to the current debate on cash-based interventions by drawing on the experience of Action Contre la Faim in southern Somalia, where it has implemented cash for work programmes since 2004. The authors conclude that cash-based interventions are a feasible option in complex emergencies as well as in highly insecure environments as long as appropriate modalities are employed and objectives are clearly set in accordance with the needs and the context. Cash as a relief response offers wide-reaching possibilities for the future from both the perspective of the donor/agency and the standpoint of the beneficiary. It enables the beneficiaries to take control of the relief themselves and to adapt it to their individual requirements in a timely manner.     

喀斯特高镉地质背景区水稻镉的富集、转运特征与机理

西南喀斯特地区土壤镉(Cd)具有"高地质背景、低污染风险"特征,但超过《土壤环境质量农用地土壤污染风险管控标准》风险管制值的区域是否仍具有低风险性,是迫切需要回答的问题.本文在罗甸县喀斯特峰丛谷地选择一个高Cd 土壤水稻种植区,开展土壤-水稻系统Cd含量特征和土壤Cd赋存形态等方面的研究,评价水稻各部位Cd的富集、转运...     

Depressional runoff cascade networks of the Des Moines Lobe of Iowa

In this study, we develop a general mathematical framework and algorithm for routing cumulative precipitation excess through depressional fill–spill cascade networks in a landscape using only information about depression morphology, local contributing areas, and potential overland flow pathways. The framework also allows for the classification of depressions according to their landscape position within a network, and calculation of precipitation- and non-precipitation-dependent network properties, including measures of network complexity and runoff connectivity. To demonstrate its use, we applied our framework to the 167,287 drained depressions of the Des Moines Lobe of Iowa, a sub-region of the Prairie Pothole Region of North America, over a large range of historically observed precipitation amounts for scenarios both neglecting and incorporating infiltration in runoff generation. Our results show that 85.3% of depressions in this region form 18,851 unique depressional runoff cascade networks, with the remainder being disjunct features. Most of the properties of the region's networks appear to conform to either a truncated power-law or lognormal distribution. For a given rainfall amount, surface runoff connectivity between depressions within networks, and between networks and off-network areas, is controlled primarily by available aggregate depressional volumetric storage and contributing area, and to a lesser degree, network complexity.     

藏东多曲河流域锶富集水化学特征及控制因素

分析高原河流地表水中锶(Sr)富集的水化学特征及其影响因素,有助于指导水资源的合理开发利用和生态环境保护.以金沙江多曲河流域地表水为例,采集地表水样品23组,综合利用相关分析、主成分分析、Gibbs模型和离子比等方法,分析该区地表水中Sr²⁺富集的水化学特征及控制因素,识别主要离子的物质来源.结果表明,多曲河流域地表水阳离子主要以Ca²⁺和Mg²⁺为主,阴离子以HCO₃^-为主.该流域水化学类型以HCO₃-Ca型为主,其次为HCO₃-Ca·Mg型.主成分分析揭示了影响多曲河水质演化的3个主成分因子,碳酸盐岩风化溶解是控制多曲河水化学组成的主要因素.ρ(Sr²⁺)超过0.40 mg·L^-1的富Sr水点占样品总量的30.43%.区内分布的闪长岩及花岗岩为多曲河流域Sr²⁺富集提供了物质基础.Sr²⁺与Ca²⁺相关性较高,二者存在伴生...     

叶面喷施纳米MnO2对水稻富集镉的影响机制

镉（Cd）容易被水稻富集,从而造成稻米中Cd含量超标,严重威胁人类健康.锰（Mn）是植物必需元素,为了探究叶面喷施纳米MnO₂对水稻富集Cd的影响机制,本研究在酸性Cd污染土壤上进行田间小区试验,在水稻抽穗早期叶面喷施0.1%、0.3%和0.5%的纳米MnO₂溶液.结果表明与对照组相比,叶面喷施不同浓度的纳米MnO₂可以有效降低水稻叶、壳和糙米中的Cd含量,增加所有部位的Mn含量,但对水稻的产量影响不大.叶面喷施纳米MnO₂后,提高了叶片光合作用效果,抑制了叶片脂质过氧化,增加了氧化应激酶的含量,从而缓解Cd对水稻的胁迫.此外,叶面喷施纳米MnO₂增加了水稻根表铁锰胶膜的含量,强化了铁锰胶膜对Cd的吸附/共沉淀作用,从而限制水稻根系吸收Cd.因此,在水稻抽穗早期叶面喷施纳米MnO₂是一种增加糙米中Mn含量和减少Cd含量的有效措施.     

Relationship between heavy metal concentrations of herbaceous plants and soils at four Pb-Zn mining sites in Yunnan, China

This paper studied the relationship between heavy metal concentrations of herbaceous plants and soils at four Pb-Zn mining sites in Yunnan, China. 50 herbaceous plant samples of 9 plant species from 4 families and 50 soil samples were collected and then ana1yzed for the tota1 concentrations of Pb, Cd, and Zn. The results showed that the average concentrations of Pb, Cd, and Zn in soil samples were 3772.83, 168.81, and 5385.65 mg/kg, respectively. The average concentrations of Pb, Cd, and Zn were 395.68, 28.14, and 1664.20 mg/kg in the shoots, and 924.12, 57.25, and 1778.75 mg/kg in the roots, respectively. Heterospecific plants at the same site and conspecific plants at various sites had different average levels of Pb, Cd, and Zn, both in the shoots and the roots. Enrichment coefficients of Pb, Cd, and Zn were greater than 1 in 2, 3, and 9 herbaceous plant samples, respectively. Translocation factors of Pb, Cd, and Zn were greater than 1 in 10, 17, and 25 herbaceous plant samples, respectively. In all 50 samples, the concentrations of Pb, Cd, and Zn between the shoots and the roots, the shoots, and the soils, and the roots and the soils had significant positive relationships.     

Subjective time in organizations: Conceptual clarification,integration, and implications for future research

Despite the rapid growth of organizational research on subjective time, the extant literature is fragmented due to a lack of conceptual clarification and integration of temporal constructs. To address this fragmentation, we synthesize temporal research from both organizational behavior and adjacent disciplines (i.e., strategy, entrepreneurship, and organizational theory) and introduce a framework that allocates temporal constructs according to their basic conceptual nature (trait–state) and level of analysis (individual–collective). We employed the Linguistic Inquiry and Word Count text analysis to determine the trait–state property of the constructs and a coding method to determine their level of analysis. This framework categorizes four generic types of subjective time: individual temporal disposition, individual temporal state, collective temporal state, and collective temporal disposition. We clarify the conceptualizations of the temporal constructs belonging to each of the four archetypes of subjective time and review their key findings in the organizational literature. Based on this integrative framework, we identify critical knowledge gaps in the current state of research and chart a future agenda with specific suggestions.     

Structural response for vented methane–air deflagrations: Effects of volumetric blockage ratio

To investigate the effects of cylinders placed parallel to the venting direction on the structural response of the vessel walls to an explosion, 25 batches of vented explosion tests were conducted in a 1 m³ rectangular vessel. Two types of structural response with different amplitudes and frequency distributions were observed and evaluated by comparing the vibration data with both the pressure data and high-speed videos. A low-amplitude structural response of approximately 150–250 m/s², which increased slightly as VBR increased, was triggered by a combination of the initial flame propagation, external explosion, Helmholtz oscillations, and the Taylor instability. A high-amplitude structural response of approximately 9500 m/s² was also observed, which decreased sharply as VBR increased. Additionally, the high amplitude response was never observed when more than two cylinders were present in the vessel. The high amplitude response was triggered due to the coupling between the acoustic wave, the flame, and the resonance of the vessel. The presence of obstacles did not increase the severity of the structural responses under the current experimental conditions. To the contrary, the presence of obstacles in the container attenuated or even inhibited the high-amplitude vibration of the container caused by the explosion.     

Worker-centered investigation of issues with procedural systems: Findings from interviews with a representative sample of workers in high-risk process industries

Issues related to procedural systems have been found to contribute to incidents in many high-risk industries such as petrochemical, oil and gas, etc. While previous research has focused on understanding issues with procedural systems from the perspective of the workers (who are the end-users of procedures), most of this research suffers from samples that only include companies with programs focused on improving safety by improving procedures. These companies may have inherent differences in their safety practices and thus the experiences of these workers may not completely represent all workers’ experiences in this domain. The purpose of this study is to gain insights into the thoughts and perceptions from a representative and broad sample of workers concerning procedure use and purpose. To improve the generalizability of previous findings, interviews were conducted with workers from a broad range of high-risk process industries to investigate issues related to procedure adherence that may be present in companies not currently implementing. Findings from a qualitative data analysis provide support for the generalizability of issues previously discovered, such as: more experience workers being more likely to deviate; procedure quality being inconsistent; and the procedure revision process being problematic. However additional prominent issues were found as well. Most importantly, this study found that adherence to procedures is often motivated by potential liability issues instead of genuine concerns for safety in organizations and many deviations from procedures were due to pressure from immediate supervisors. These findings suggest a relationship between the effectiveness/quality of procedural systems and the safety climate of the organization or work unit.