Evaluating the Impact of Partial Factorial Invariance on Selection in Two Populations.

Studies of factorial invariance examine whether a common factor model holds across multiple populations with identical parameter values. Partial factorial invariance exists when some, but not all, parameters are invariant. The literature on factorial invariance is unclear about what should be done if partial invariance is found. One approach to this problem evaluates the impact of partial invariance on accuracy of selection on the basis of a composite of the measures whose factor structure is being studied. Assuming a single-factor model holds, accuracy of selection using the composite is evaluated under varying degrees of partial invariance. A variety of examples are presented with discussion of extensions and limitations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impact of Ethanol on Benzene Plume Lengths: Microbial and Modeling Studies

Recent legislation in several states has called for the removal of methyl tert-butyl ether (MTBE) from gasoline. In order to comply with Federal Clean Air Act requirements for carbon monoxide and ozone attainment, ethanol is being considered as a replacement for MTBE. The objective of this study is to evaluate the potential impact of ethanol on benzene plume lengths in subsurface environments following accidental spills of ethanol-blended gasoline. Two types of studies were conducted here. First, laboratory studies were performed using a pure culture indigenous to a gasoline-contaminated aquifer to evaluate the effect of ethanol on the rate of benzene biodegradation under aerobic conditions. Results from microbial studies showed that the biodegradation of 25 mg/L benzene was severely inhibited in the presence of 25 mg/L ethanol. While the enzymes responsible for benzene biodegradation by the culture were inducible, ethanol degradation appeared to be constitutive. Second, a two-dimensional model was developed to quantify the impact of ethanol on benzene plume lengths using weighted-average aerobic and anaerobic biodegradation rates for benzene in the presence and absence of ethanol. Model simulations indicated that benzene plume lengths are likely to increase by 16–34% in the presence of ethanol.     

Responsivity to Two Odorants, Androstenone and Amyl Acetate, and the Affective Impact of Odors on Interpersonal Relationships.

Substantial variation exists in the importance of olfaction in influencing individuals' preferences, yet the sources of this variation remain elusive. The authors explored responsivity to 2 odorants as 1 potential source. Participants (N = 258) completed the Affective Impact of Odor Scale and were assessed for responsivity to the putative human pheromone androstenone and amyl acetate. Results showed a significant relationship between odorant responsivity and self-reports of the influence of odors. People able to smell androstenone more commonly reported odors as having a negative effect on interpersonal relationships than did people anosmic to androstenone, whereas responsivity to amyl acetate was associated with positive effects of odors on relationships. Responsivity to certain odorants may be an important factor affecting human social interactions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Testosterone as a Social Inhibitor: Two Case Studies of the Effect of Testosterone Treatment on Language.

This study aimed to correlate testosterone levels with natural written language in 2 people undergoing testosterone therapy. Two participants, a man receiving treatment for loss of upper-body strength and a female-to-male transgendered individual, supplied records of injections over 1-2 years along with e-mails or journal entries as writing samples. Results showed that higher testosterone levels correlated with reduced use of words related to social connections. Language relating to anger, sexuality, and achievement was unrelated to testosterone levels. It appears that testosterone steers attention away from social connections but not necessarily toward concerns with aggression or sexual activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

高炉炉墙状况诊断及冷却壁状态在线检测系统开发与应用

介绍了济钢第一炼铁厂 6#高炉利用高炉冷却壁进出水温差实施炉体检测的装备配置和通过水温差及炉体热负荷间接判断炉墙结厚、渣皮脱落以及冷却壁状态诊断的应用情况。实践证明 ,该在线检测系统能及时发现冷却水管漏水、堵塞等故障 ,有利于延长冷却壁的寿命 ,且该系统软件界面友好、直观 ,对准确判断、分析高炉炉况有直接的帮助意义     

蓄热式板坯连续加热炉炉底强度的分析与计算

蓄热式加热炉炉底强度的合理选取与炉子的炉长、实际加热能力、加热质量、炉子的运行工况(燃烧负荷、炉压、检修周期、炉体寿命等)密切相关。而蓄热式加热炉炉底强度的计算目前尚无详细资料。通过济钢中板3#蓄热式加热炉设计中对炉底强度的选取,经使用与炉子实际能力基本吻合。     

基于复变函数理论和D-P屈服准则的并行隧道合理间距

综合利用复变函数理论、解析延拓法和Schwarz交替法揭示相邻水平并行隧道的应力分布特征.在此基础上,结合考虑了中间主应力效应的D-P屈服准则建立相邻水平并行隧道力学模型.提出并行隧道塑性区贯穿半径的概念,建立求解方程,并通过数值模拟证明其正确性.采用隧道间塑性区临界贯穿状态下的间距作为隧道合理间距,与数值模拟软件FLAC3D计算得到的围岩位移量和沉降量随间距变化至基本不发生变化时所对应的隧道间距有较高的吻合性,从而表明其作为相邻水平并行隧道合理间距的可行性.     

谈住宅楼外墙抹灰层裂缝的防治与处理

建筑物外墙抹灰层经常出现裂缝、渗水、空鼓、甚至脱落现象,正确预防和处理好建筑物外墙抹灰层的裂缝是保证外墙施工质量的前提,文章针对住宅楼外墙抹灰层裂缝产生的原因进行了分析,制定了预防和处理措施。     

从湖南有色金属出口情况看入世对有色工业的冲击与挑战

文章综合分析了湖南有色金属“九五”期间的出口贸易状况，并对影响出口的因素及出口市场环境进行了分析，提出了加入WTO后，扩大有色产品出口的对策措施。     

青海肯德可克矿区钴多金属矿地质特征及成因初探

运用地质、物化探等技术,采用槽探、钻探及地物化剖面测量等技术手段,研究肯德可克矿区内钴多金属矿的成矿地质背景和控矿因素。研究结果表明,肯德可克矿区是一个典型的复合型矿床,铁、金、钴、铋、铅、锌、钼和铜等元素均可独立构成矿体,成矿元素既可共生,也可伴生,在空间上具有密切的联系。矿体主要为泥钙质硅质岩,呈条带状和蠕虫状,具明显的热塑性变形特征,其成因可归结为热水沉积-叠加改造型矿床。     

Impact of Solids Formation and Gas Production on the Permeability of ZVI PRBs

The permeability of zero-valent iron permeable reactive barriers (ZVI PRBs) may be reduced by the production of gas and solid precipitates. The reduction in permeability was examined using column experiments, which showed that permeability loss was correlated with influent oxidant concentration. The column containing 100??mg/L nitrate experienced the greatest loss, approximately two orders of magnitude over the course of 200 pore volumes. However, the permeability loss owing to precipitated solids was largely independent of oxidant concentration, accounting for only 24% of the observed loss in the 100??mg/L nitrate column, suggesting that the majority of loss was attributable to gas, not precipitates. Geochemical modeling corroborated these findings, indicating that precipitation of solids in the 100??mg/L nitrate system does not account for more than a 10% permeability reduction. These findings suggest that in field PRBs in which a high reduction in permeability is observed, gas production may be implicated. Design choices that impede gas migration out of ZVI PRBs, such as capping, must be considered in light of the possibility of a high potential for permeability reduction.     

Impact of Elaboration on Socially Desirable Responding and the Validity of Biodata Measures.

The current study investigated the impact of requiring respondents to elaborate on their answers to a biodata measure on mean scores, the validity of the biodata item composites, subgroup mean differences, and correlations with social desirability. Results of this study indicate that elaborated responses result in scores that are much lower than nonelaborated responses to the same items by an independent sample. Despite the lower mean score on elaborated items, it does not appear that elaboration affects the size of the correlation between social desirability and responses to biodata items or that it affects criterion-related validity or subgroup mean differences in a practically significant way. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

钼及碳含量对铌钼钨合金高温机械性能的影响

介绍了钨、钼、氧、碳含量不同的Nb-Mo-W合金于1773K时的拉伸和压缩试验情况及其变形和断裂行为。     

Immigration and Construction: Analysis of the Impact of Immigration on Construction Project Costs

There are an estimated 11 million illegal immigrants currently residing in the United States. Of this population, research shows that approximately 19% work in the construction industry, comprising around 14% of all construction workforces. The main objectives of this research are to (1) to predict possible effects of immigration and immigration reform legislation on worker wages and (2) to assess the likely wage increase due to decreased supply of immigrant labor. In the Washington, D.C. metropolitan region, the construction workforces for low-skilled trades such as concrete, masonry, drywall, painting, flooring, and roofing are comprised of approximately 55% illegal immigrant. Based on four factors evaluated in this research (1) prevailing wage provision in legislation; (2) forced tax compliance of the workforce; (3) market correction from currently depressed wages due to immigrant penetration into the workforce; and (4) a labor shortage resulting from a depleted supply of immigrant labor, proposed legislation could increase the cost of trade labor up to almost 70% in the Washington, D.C. metropolitan area. Overall labor costs for projects could increase by almost 18%, and total project costs could rise almost 12% in the Washington, D.C. metropolitan region.     

Relative Abundance of Monovalent and Divalent Cations and the Impact of Desiccation on Geosynthetic Clay Liners

Laboratory experiments were conducted on a geosynthetic clay liner (GCL) containing Na–bentonite to determine how the swell index and hydraulic conductivity of GCLs are affected by wet-dry cycling with solutions having different relative abundance of monovalent and multivalent cations. Relative abundance of monovalent and multivalent cations was characterized by the RMD of the test solution, which is defined as the ratio of the total molarity of monovalent cations to the square root of the total molarity of multivalent cations at a given ionic strength. RMD was found to control the final swell index, relative abundance of monovalent and divalent cations in the final exchange complex, and the final hydraulic conductivity of bentonite exposed to wet-dry cycling. Ionic strength affects the number of wet-dry cycles required for a change in hydraulic conductivity to occur and the rate of change in swell index. Large increases in hydraulic conductivity and loss of swelling capacity occurred for solutions having RMD ? 0.07?M1/2. Modest or small changes in hydraulic conductivity and swell index were obtained when the RMD was ≥ 0.14?M1/2. These findings suggest that chemical analysis of the pore water in cover soils may prove useful in evaluating the compatibility of GCLs and cover soils used in applications where wet-dry cycling may occur.     

The Impact of Deployment Length and Experience on the Well-Being of Male and Female Soldiers.

This study examined the effects of stressor duration (deployment length) and stressor novelty (no prior deployment experience) on the psychological health of male and female military personnel returning from a peacekeeping deployment. The sample consisted of men (n = 2,114) and women (n = 1,225) surveyed for symptoms of depression and posttraumatic stress. The results confirmed the hypotheses. Longer deployments and 1st-time deployments were associated with an increase in distress scores. However, the relationship between deployment length and increased distress was found only for male soldiers. The findings demonstrate the importance of considering the impact of exposure to long-term occupational stressors and confirm, in part, previous research that has demonstrated a different stress response pattern for men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimental and Theoretical Studies for the Behavior of Strip Footing on Oil-Contaminated Sand

This paper presents the results of a series of plain-strain model tests carried out on both clean sand and oil-contaminated sand loaded with a rigid strip footing. The objectives of this study are to determine the influence of oil-contaminated sand on the bearing capacity characteristics and the settlement of the footing. Contaminated sand layers were prepared by mixing the sand with an oil content of 0–5% with respect to dry soil to match the field conditions. The investigations are carried out by varying the depth and the length of the contaminated sand layer and the type of oil contamination. A plain-strain elastoplastic theoretical model with an interface gap element between footing and the soil is carried out to verify the test results of the model. It is shown that the load-settlement behavior and ultimate bearing capacity of the footing can be drastically reduced by oil contamination. The bearing capacity is decreased and the settlement of the footing is increased with increasing the depth and the length of the contaminated sand layer. The agreement between observed and computed results is found to be reasonably good in terms of load-settlement behavior and effect of oil contamination on the bearing capacity ratio. A comparison between the model results and the prototype scale (B = 1.0?m) results are also studied.     

铜镍硫化矿尾矿中有价金属的湿法提取研究

以硝酸为氧化剂、硫酸为添加剂的混酸体系用于铜镍硫化矿尾矿中镍、铜、钴等有价金属的浸出,镍、铜、钴浸出率分别可达91.5%,85.0%和54.6%。放大试验表明,这一混酸浸出方法的效果良好、操作简便稳定。     

Body tilt effect on the reproduction of orientations: Studies on the visual oblique effect and subjective orientations.

Body tilt effects on the visual reproduction of orientations and the Class 2 oblique effect (E. A. Essock, 1980) were examined. Body tilts indicate whether the oblique effect (i.e., lower performance in oblique orientations than in vertical-horizontal orientations) is defined in an egocentric or a gravitational reference frame. Results showed that the oblique effect observed in upright posture disappeared in tilted conditions, mainly due to a decrease in the precision of the vertical and horizontal settings. In tilted conditions, the subjective visual vertical proved to be the orientation reproduced the most precisely. Thus, the oblique effect seemed to be not purely gravitationally or egocentrically defined but, rather, to depend on a subjective gravitational reference frame tilted in the same direction as body tilts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)