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1.
To enhance the understanding of the behavior and effects of the precipitation of MnO2 particles in the subsurface generated during in situ chemical oxidation (ISCO) using permanganate, laboratory batch experiments were completed to examine the influence that varied reaction matrix conditions have on the generation and properties of manganese oxides. The conditions examined include organic material type and concentration, permanganate concentration, pH, and the presence of calcium (as a representative divalent cation) in solution. Experimental studies included: (1) spectrophotometric examination of permanganate depletion and manganese oxides generation over time during reactions with trichloroethene; (2) scanning electron microscopy analyses of manganese particle morphology; (3) particle size distribution (filtration) characterization studies; and (4) optical particle sizing and numeration studies. Bench-scale, batch experiments were conducted to focus on fundamental chemical properties affecting particle development under varied potential environmental conditions. The amount of manganese oxides particles that develop, grow, and potentially settle as a result of permanganate ISCO of organic contaminants is a function of the particle size and concentration, the time allowed for particle development, and the impact of matrix conditions on the ability of particles to agglomerate. 相似文献
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Michelle Abraham 《电子产品世界》2008,(7)
数字视频编码和解码芯片目前需求量很大.在未来几年里,这种芯片的市场将更加强劲地增长.推动这个市场增长的因素有三个:一个是全球范围的从模拟电视向数字电视的过渡,这种过渡将刺激数字接收机和基础设施设备的需求;另一个因素是手机、便携式播放机和汽车内的移动视频功能日益流行;第三个因素是数字视频标准的持续发展将推动对提供高性能芯片的新需求. 相似文献
4.
This report summarizes the panel held at the 109th Annual Convention, American Psychological Association, August 26, 2001, San Francisco. The chair was William Glover and the speakers were Samuel Gerson, Karen Maroda, and Andre Patsalides. The invited symposium was directed at discussing different perspectives related to the presence of desire in the analytic process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Williams Paula G.; Wasserman Michelle S.; Lotto Andrew J. 《Canadian Metallurgical Quarterly》2003,22(1):3
In 2 studies, the relation between measures of self-assessed health (SAH) and automatic processing of health-relevant information was investigated. In Study 1, 84 male and 86 female undergraduate students completed a modified Stroop task. Results indicated that participants with poorer SAH showed enhanced interference effects for illness versus non-illness words. In Study 2, 27 male and 30 female undergraduate students completed a self-referent encoding task. Results offered a conceptual replication and extension of Study 1 by confirming the specificity of the relation between SAH measures and automatic processing of health (vs negative or positive general trait) information. These studies provide evidence that individual differences in SAH are reflected in schematic processing of health-relevant information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Feedback provided to Ss and 3rd parties from intra- and extramural investigators following the completion of research involving an agency's clients or staff is described. Ss were from the division of a public health department that provides mental health and substance abuse services in a city with 740,000 people. The division's research requirements include submission of annual progress reports and final reports. Of 135 studies conducted over 12 yrs, annual reports were received from 37% of investigators, and final reports from 30%. There were no significant differences based on investigator discipline or affiliation. Professional and ethical implications are discussed, including adequacy of professional training, the need for mechanisms to ensure compliance with ethical standards, the obligations of clinic directors, and the impact on public academic liaison programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
The development of verbal and spatial working memory was investigated with an interference paradigm. Memory spans were obtained from 3 groups (8-, 10-, and 19-yr olds) under 6 different conditions: Two primary memory tasks (1 verbal, 1 spatial) were administered in isolation and in conjunction with 2 versions of a secondary task. The primary tasks required recalling a series of visually presented digits and recalling the locations of Xs in a series of visually presented grids. The secondary tasks required reporting the color of the stimuli as they were presented using either a verbal or a spatial response. Analyses revealed that all age groups showed domain-specific interference (i.e., interference by a secondary task from the same domain as the primary task), but only the 8-yr-olds also showed nonspecific interference (i.e., interference by a secondary task from a domain different than the primary memory task), suggesting that at least some executive functions do not reach adult levels of efficiency until approximately age 10. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
N. Azam L.A. Douglas S.W. McConnell . 《Hemodialysis international. International Symposium on Home Hemodialysis》2004,8(1):107-108
Heparin is almost universally used as an anticoagulant during hemodialysis. Rare but serious side effects of heparin therapy include heparin‐induced thrombocytopenia (HIT) and anaphylaxis, and these may lead to significant mortality and morbidity if left unrecognized. We are reporting a patient who developed HIT followed by an anaphylactoid reaction. This 8‐year‐old girl with Joubert's syndrome developed end‐stage renal disease secondary to nephronophthisis. She had a Permacath double‐lumen hemodialysis catheter placed in the right internal jugular vein and was started on hemodialysis using an Asahi B10 65 Dialyzer on 1/28/03. The platelet count at that time was 246 × 103/mL. Beef lung heparin was used for anticoagulation. She was admitted for living related donor renal transplant on 2/10/03 but was found to be thrombocytopenic with a platelet count of 49 × 103/mL. The transplant was postponed, a sepsis work‐up was performed, and she was started on antibiotics pending culture results. Hemodialysis was continued with heparin anticoagulation, and despite an improvement in the platelet count she had an acute anaphylactoid reaction 2 days later. The reaction occurred 20 min after starting her hemodialysis treatment and presented as acute onset of bronchospasm, agitation, and chest discomfort. She improved with nebulized albuterol and subcutaneous epinephrine. A review of her records revealed that she had received 6 hemodialysis treatments. The platelet count on 2/3/03, after 3 hemodialysis treatments, had been 242 × 103/mL and on 2/8/03 after 5 treatments the platelet count was 72 × 103/mL. HIT with anaphylaxis was suspected. Heparin was discontinued and the platelet count had returned to normal within 2 days. The diagnosis was confirmed by a positive heparin‐associated antibody test. While HIT is recognized as a complication in 1–5% of patients treated with heparin and has been well described in the literature, we could only find 2 reported cases of heparin‐induced anaphylaxis and in both cases there was accompanying thrombocytopenia. This patient further illustrates a possible linkage between these two phenomena. HIT is an important cause of thrombocytopenia in a patient on hemodialysis and continued exposure to heparin may induce anaphylaxis. 相似文献
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10.
Kevin Curran Michelle Murray David Stephen Norrby Martin Christian 《New Review of Information Networking》2013,18(1-2):47-59
Libraries, as we know them today, can be defined by the term Library 1.0. This defines the way resources are kept on shelves or at a computer behind a login. These resources can be taken from a shelf, checked out by the library staff, taken home for a certain length of time and absorbed, and then returned to the library for someone else to avail of. Library 1.0 is a one-directional service that takes people to the information they require. Library 2.0 – or L2 as it is now more commonly addressed as – aims to take the information to the people by bringing the library service to the Internet and getting the users more involved by encouraging feedback participation. This paper presents an overview of Library 2.0 and introduces web 2.0 concepts. 相似文献