井矿盐开发所致的辐射水平

本文报道了自贡市井矿盐开发所致的辐射水平。井矿盐开发的主要废弃物－卤泥中＾２３８Ｕ，＾２２６Ｒａ，＾２３２Ｔｈ的天然放射性核素比活度比四川省土壤中相应核素平均值高１－２个数量级，且造成卤泥堆积场和局部生产环境陆地γ辐射剂量率高出自贡市环境陆地γ辐射平均值的２．０－４８．３倍，最主超过１６５倍。部份卤泥和盐厂附近江河排放口底泥中天然放射性废物标准。     

IMPACTS OF AGRICULTURAL DRAINAGE WELL CLOSURE ON CROP PRODUCTION: A WATERSHED CASE STUDY1

ABSTRACT: Much of north-central Iowa is characterized by flat topography, shallow depressions, and poor natural surface drainage. Land drainage systems comprising of tile drains and agricultural drainage wells (ADWs) are used as outlets for subsurface drainage of cropland under corn and soybean production. Studies have shown that these drainage systems, mainly the ADWs, are potential routes for agricultural chemicals to underground aquifers. To protect the region's vital groundwater resource, researchers are evaluating alternative outlets ranging from complete closure of existing ADWs (and creation of wetlands) to continued use of ADWs and chemical management in a comprehensive policy framework. This paper presents the results of a study designed to provide government jurisdictions, farmers, and land managers information for assessing the impact of closing ADWs on crop production. The study couples a geographic information systems database for a 471-hectare watershed in Humboldt County, Iowa, with a groundwater flow model (MODFLOW) and an empirical crop yield loss model to predict long-term effects of complete closure of ADWs on crop production. The cropland areas inundated and the relative crop yield loss due to ADW closure are determined as a function of long-term climatic data. The results indicate that elimination of drainage outlets in the watershed could result in ponding of low-lying areas and poorly drained soils, making them unsuitable for crop production. Such wetness also decreases the efficiency of production in the no-ponding areas by isolating fields, and the crop yield loss can be reduced by an annual average of about 18 percent.     

采油射流泵内流场数值模拟

采油射流泵内流场是具有逆压力梯度的强湍流场，扩散管部分具有不规则边界。采用代数法生成扩散器贴体坐标系统；并选择使用高Ｒｅ数ｋ－ε。模型及考虑逆压力梯度影响的壁面函数法对射流泵整体流场进行数值模拟。将理论结果与试验值进行对比分析，二者基本符合，数值模拟的可靠性得到了验证。     

OVERPUMPED ARTESIAN WELLS AMONG A WELL GROUP1

ABSTRACT. Overpumped artesian wells are defined and explained. Unified well equations which can be used for artesian, gravity and overpumped artesian wells are derived under both the steady and transient conditions of flow. The location of the boundary between artesian and gravity steady and transient flow systems in artesian aquifers, due to multiple wells among which overpumped artesian wells may exist, is explained.     

抽油井安全监控系统

在论述影响抽油井正常工作诸因素的基础上,为保证安全生产作业,提出了一种性能稳定、可靠的监控系统,并对该系统中采用的传感器件及测量电路等进行了讨论     

Who stays proactive after entrepreneurship training? Need for cognition,personal initiative maintenance,and well‐being

Personal initiative training is a promising way to increase entrepreneurial personal initiative, which is a key behavior for successful entrepreneurship. Although personal initiative training has been shown to promote personal initiative, little is known about how this proactive behavior can be maintained over time and what the consequences are. The training transfer literature suggests that training effects usually decline with time. It is not clear, however, which factors contribute to personal initiative maintenance and which benefits go along with it. In a randomized controlled field experiment with 912 microentrepreneurs in Lomé, Togo, we investigate the influence of need for cognition—a cognitive factor driving proactive behavior—on personal initiative maintenance after training. In addition, we examine the effect of need for cognition on the well‐being consequences of personal initiative maintenance. We show that people high in need for cognition tend to maintain posttraining personal initiative longer than those low in need for cognition. However, contrary to our predictions, need for cognition has no effect on the level of well‐being that results from personal initiative maintenance. Our findings contribute to a better understanding of personal initiative and its maintenance and could be used to increase training effectiveness.     

卧式滤筒除尘器的气流组织模拟研究

为了研究卧式滤筒除尘器内部气流的不均匀性问题,采用计算流体动力学软件Fluent对卧式滤筒除尘器内部气流组织进行数值模拟研究。参考目前市面上常见卧式除尘器,设计有、无挡板的2种卧式滤筒除尘器模型,通过分析2种模型下过滤过程的速度分布和滤筒流量分配情况得出:在无挡板模型下存在射流冲刷、气流分布不均等问题,而在进风口加设挡板能解决气流冲刷问题,滤筒流量分配得到明显改善;在相同滤室高度下分别对挡板角度为150°,160°,165°,170°,175°,180°对比发现,挡板角度在165°~170°时其内部气流组织能达到均匀标准。     

套管环空压力恢复与泄压预测模型研究

针对气井套管环空带压问题,通过研究气体在套管水泥环内的渗流规律,建立了气体渗流的连续性方程和运动方程,并求解出气体在水泥环中的渗流速率。通过分析井口泄压时针型阀处的气体流动状态,得出泄压时的气体泄放速率。以气体渗流速率和泄放速率为基础,结合井口的气体状态方程,分别建立了套管环空压力恢复与泄压预测模型。根据现场A气井实际数据进行实例计算,研究结果表明:所建模型计算的套管环空压力值与现场实测数据吻合,验证了模型的准确性。研究结果对套管环空带压的诊断评估和环空压力的控制具有重要意义。     

Getting away from them all: Managing exhaustion from social interaction with telework

Drawing on the conservation of resources and recovery literatures, we examine how social job characteristics—interpersonal interaction, job interdependence, and external interaction—relate to work exhaustion. We then explore the efficacy of a part‐time telework (PTT) practice in alleviating work exhaustion associated with social interaction. Study 1 is a within‐subject assessment of work exhaustion before and after a PTT practice; participants are 51 information technology professionals in a financial services firm. Study 2 is a between‐subject assessment of work exhaustion among part‐time teleworkers and non‐teleworkers; participants are 258 U.S. workers spanning a variety of industries. Study 2 replicated the model tested in Study 1, and we extended the conceptualization of interpersonal interaction to examine both quantity and quality of interaction. In both studies, PTT provided a recovery opportunity, attenuating the relationship between interpersonal interaction and work exhaustion; however, after PTT but not before, work exhaustion increased as external interaction increased. In Study 2, work exhaustion decreased as interaction quality increased; in contrast, work exhaustion increased as interaction quantity increased and PTT attenuated this relationship. Our recommendations aim to help balance telework practices in light of social job characteristics and their opposing effects on work exhaustion. Copyright © 2017 John Wiley & Sons, Ltd.     

Under what conditions does job control moderate the relationship between time pressure and employee well‐being? Investigating the role of match and personal control beliefs

Drawing upon the concept of match, this two‐wave study of 206 employees investigated job control (facets of autonomy) and personal control beliefs (locus of control, LOC) as moderators of time pressure–work engagement (WE) and the time pressure–general subjective well‐being (SWB) relationships. It was hypothesized that autonomy would accentuate the positive relationship of time pressure with WE and attenuate the negative relationship with SWB and that these moderations would occur only for employees with an internal LOC. Additionally, it was expected that a facet of job control (timing autonomy) that matched the specific demand (time pressure) would be more likely to act as a moderator than “less‐matching” facets (decision making or method autonomy). The results revealed that the interaction between time pressure, autonomy, and LOC for WE was strongest and for SWB only significant when the timing facet of autonomy served as the moderator (thus, when the autonomy facet matched the demand). However, the pattern of moderation was contrary to that expected. When time pressure increased, high autonomy became beneficial for the WE of employees with an external LOC but detrimental for the WE and SWB of employees with an internal LOC. Explanations for the unexpected findings are provided. Copyright © 2016 John Wiley & Sons, Ltd.