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Low-permeability reservoirs are generally characterized by low porosity and low permeability. Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor. In recent years, hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing fluid. However, the transportation of the proppant is inefficient in the low-viscosity fluid, and the proppant has a low piling-up height in fracture channels. These key challenges restrict the fluid (natural gas or oil) flow in fracture channels and their functional flow areas, reducing the profits of hydrocarbon exploitation. This study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber. Its structure was similar to that of dandelion seeds, and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional proppant. Moreover, the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models (tortuous fracture model, rough fracture model, narrow fracture model, complex fracture model, large-scale single fracture model, and small-scale single fracture model). Experimental results indicated that, compared with the traditional proppant, the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid. Compared with the traditional proppant, the dandelionbased bionic proppant had 0.1-4 times longer transportation length, 0.3-5 times higher piling-up height, and 2-10 times larger placement area. The newly developed proppant also had some other extraordinary features. The tortuosity of the fracture did not influence the transportation of the novel proppant. This proppant could easily enter the branch fracture and narrow fracture with a high packing area in rough surface fractures. Based on the aforementioned characteristics, this novel proppant technique could improve the proppant transportation efficiency in the low-viscosity fracturing fluid and increase the ability of the proppant to enter the secondary fracture. This study might provide a new solution for effectively exploiting low-permeability hydrocarbon reservoirs. [ABSTRACT FROM AUTHOR]

Copyright of Consumer Behavior Review (CBR) is the property of Consumer Behavior Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Consumer Behavior Review (CBR) is the property of Consumer Behavior Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report ab-initio calculations of water absorption in Y2Mo3O12. The absorption geometry of H2O in Y2Mo3O12 and the binding property between H2O and Y2Mo3O12 have been first identified. Our calculated results show that water is chemisorbed in Y2Mo3O12 with O of the water binding to the Y3+ cation, which is further strengthened by hydrogen bonding between each of the hydrogen atoms of H2O and the bridge O in Y2Mo3O12, shared by polyhedrons YO6 and MoO4. The absorption of water leads to a reduced angle of Y-O-Mo and shortened Y-Mo distance, and consequently volume contraction of the material, almost linearly with the increasing number of water molecules per unit cell, up to eight in total. In addition, our phonon calculation show that the transverse vibration of Y-O-Mo is restricted due to water absorption, which in turn hinders the NTE, as it is mainly originated from this vibrational mode. Our results clarify further the fundamental mechanisms of the large volume shrinkage and the lost NTE of the framework oxide due to water absorption. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the role of catastrophizing as a mediator and moderator between life stress and depression in a sample of workers’ compensation patients with chronic musculoskeletal pain. Pain intensity, life stress (especially work and financial stress), and catastrophizing contributed significantly to depression. Catastrophizing was found to be partially mediating the relationship between life stress and depression and a moderator between social stress and depression. The results supported the role of catastrophizing as a cognitive vulnerability-stress factor related to depression in chronic pain patients. Screening for life stress and intervening early to prevent catastrophizing from occurring in the workers’ compensation rehabilitation process may reduce psychosocial distress and enhance the overall effectiveness of rehabilitation programming for workers’ compensation patients with chronic pain. [ABSTRACT FROM AUTHOR]

This study analyzed the Rehabilitation Services Administration (RSA) case service report (RSA-911) data for fiscal year 2004 to examine effects of demographic characteristics, work disincentives, and vocational rehabilitation services patterns on employment outcomes of persons with traumatic brain injuries (TBI). The results indicated that European Americans (53%) had appreciably higher competitive employment rates than Native American (50%), Asian Americans (44%), African Americans (42%), and Hispanic/Latino Americans (41%). Clients without co-occurring psychiatric disabilities had a higher employment rate (51%) than those with psychiatric disabilities (45%). Clients without work disincentives showed better employment outcomes (58%) than those with disincentives (45%). An important finding from this analysis was the central role of job search assistance, job placement assistance, and on-the-job support services for persons with TBI in predicting employment outcomes. A data mining technique, the exhaustive CHAID analysis, was used to examine the interaction effects of race, gender, work disincentives and service variables on employment outcomes. The results indicated that the TBI clients in this study could be segmented into 29 homogeneous subgroups with employment rates ranging from a low of 11% to a high of 82%, and these differences can be explained by differences in work disincentives, race, and rehabilitation service patterns. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to explore the relationships between university employees' work-related cultural values and expected leadership communication styles in two cultures, Taiwan and the United States. Hofstede's (1984; 2001) Cultural Theory served as the theoretical foundation for this study. A questionnaire was completed by 303 university employees at a National Taiwanese University and at a large state university in the United States. Several significant relationships were found between work-related cultural values and expected leadership communication styles for these employees. The ways in which different work-related cultural values affect subordinates' expected leadership decision-making styles and expected leadership conflict-management styles were identified. [ABSTRACT FROM AUTHOR]

A correction to the article "Service Patterns Related to Successful Employment of Persons With Traumatic Brain Injury in Vocational Rehabilitation," published in a 2007 issue is presented.