163 research outputs found

    Phosphordüngewirkung karbonisierter Biogasgärreste

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    P-recycling from biogas residue may play a future key role for sustainable P supply in organic farming. However, in particular transportation costs of residue need to be reduced e.g. by pretreatment. One approach is carbonization by pyrolysis or hydrothermal carbonization (HTC). In a pot trial with maize on a P-deficient, acidic sandy loam P uptake after application of two chars from pyrolysis (400 and 700 °C) and HTC (6 and 8 h dwell time) all made of the same residue was compared to P uptake after application of the raw residue and water soluble KH2PO4 respectively. P uptake was the same for KH2PO4, raw residue and both HTC treatments, but was significant lower in treatments with pyrolytic chars. Neither dwell time nor temperature had an effect. However, whereas pyrolysis raised P concentration, in HTC chars it was the same as in the raw residue. Also P was extracted from soil of pots without plants at beginning, half and end of the trial using H2O, CAT, CAL and Na-formate respectively. For CAT, CAL and Na-formate significant correlations between P uptake by maize and extractable P at all dates exist, whereas for H2O this was only true for extractable P at the end of the trial

    Cognitive and linguistic factors affecting alphasyllabary language users comprehending Chinese text

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    Two groups of 13 to14-year-old alphasyllabary language users (mainly Hindi and Urdu), in integrated or designated school settings (respectively 40 and 48 students), were compared with 59 Chinese students in comprehending 4 elementary Chinese texts, each with three inferential questions requiring short open-ended written answers. Three constructs each with two indicators were hypothesized to predict text comprehension differentially in the three groups: verbal working memory, orthographic processing and sentence processing. The 147 students also completed a short questionnaire on their reading and writing of Chinese, a 43-item Students’ Approaches to Learning and a non-verbal general intelligence test. Multivariate analyses of variance and hierarchical multiple regression analyses point to the significant contribution of verbal span working memory, orthographic choice in context and sentence processing in Chinese to Chinese text comprehension. Educational implications include strengthening teaching the structure and function of Chinese characters and words to enhance text comprehension

    Differential contribution of psycholinguistic and cognitive skills to written composition in Chinese as a second language

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    This is the author accepted manuscript. The final version is available from Springer via the DOI in this record.This study examined the contribution of the constructs of orthographic processing (orthographic choice and orthographic choice in context), syntactic processing (grammaticality and sentence integrity), and verbal working memory (two reading span indicators) to written Chinese composition (narration, explanation, and argumentation) in 129 fifteen-year-old L2 learners. A matrix task was also administered as a control task to tap cognitive flexibility. Structural Equation Modeling (SEM) analysis with written composition as a latent variable revealed orthographic processing and working memory as two significant, independent contributors, whereas the unique contribution of syntactic processing was not significant. Subsequent SEM analysis with narration, explanation, and argumentation as separate endogenous variables found varied patterns of the contribution of each latent predictor to written composition in different genres. These patterns are discussed in light of the importance of attention to learners’ developmental stage and genre-sensitive measures to capture the psycholinguistic and cognitive underpinnings of written composition in L2 Chinese

    The conversion of garages for residential purposes in Los Angeles County : impacts and potential as a housing resource

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    Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1992.Includes bibliographical references (p. 92-98).by Dora K. Leong.M.C.P

    Sustainable green construction management: schedule performance and improvement

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    Over the last few years, the green building movement in Singapore has leaped bountifully. While environmental sustainability for greener construction has been emphasized, rare research has been conducted to analyze performance of green construction projects. As a result, this study aims to address schedule performance of green building construction projects and to provide some recommendations that may improve the targeted performance. To achieve this objective, a questionnaire was developed and the responses from 30 companies were analysed, and interviews with 6 project managers were conducted to further supplement and substantiate the survey results. The analysis reported that green building projects required an average of 8% more time than traditional building projects of similar size and characteristics. In addition, on average, these projects were delayed by 4.8% when compared with their as-planned schedules. Lastly, a list of recommendations was also introduced, aiming to ameliorate the schedule performance. This study will offer a benchmark for the industry to gauge the overall duration and performance of green building construction projects

    SINGLE-SHELL TANK INTEGRITY PROJECT ANALYSIS OF RECORD-PRELIMINARY MODELING PLAN FOR THERMAL AND OPERATING LOADS

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    This document is a Phase I deliverable for the Single-Shell Tank Analysis of Record effort. This document is not the Analysis of Record. The intent of this document is to guide the Phase II detailed modeling effort. Preliminary finite element models for each of the tank types were developed and different case studies were performed on one or more of these tank types. Case studies evaluated include thermal loading, waste level variation, the sensitivity of boundary effects (soil radial extent), excavation slope or run to rise ratio, soil stratigraphic (property and layer thickness) variation at different farm locations, and concrete material property variation and their degradation under thermal loads. The preliminary analysis document reviews and preliminary modeling analysis results are reported herein. In addition, this report provides recommendations for the next phase of the SST AOR project, SST detailed modeling. Efforts and results discussed in this report do not include seismic modeling as seismic modeling is covered by a separate report. The combined results of both static and seismic models are required to complete this effort. The SST AOR project supports the US Department of Energy's (DOE) Office of River Protection (ORP) mission for obtaining a better understanding of the structural integrity of Hanford's SSTs. The 149 SSTs, with six different geometries, have experienced a range of operating histories which would require a large number of unique analyses to fully characterize their individual structural integrity. Preliminary modeling evaluations were conducted to determine the number of analyses required for adequate bounding of each of the SST tank types in the Detailed Modeling Phase of the SST AOR Project. The preliminary modeling was conducted in conjunction with the Evaluation Criteria report, Johnson et al. (2010). Reviews of existing documents were conducted at the initial stage of preliminary modeling. These reviews guided the topics that were explored in the SST preliminary modeling. The reviews determined the level of detail necessary to perform the analyses of the SSTs. To guide the Phase II detailed modeling effort, preliminary finite element models for each of the tank types were developed and different case studies were performed on one or more of these tank types. Case studies evaluated include thermal loading, waste level variation, the sensitivity of boundary effects (soil radial extent), excavation slope or run to rise ratio, soil stratigraphic (property and layer thickness) variation at different farm locations, and concrete material property variation and their degradation under thermal loads. Conclusions were derived from case studies on one of the tank types when no additional runs of similar cases on other types of tanks were found necessary to derive those conclusions. The document reviews provided relatively complete temperature histories for Type IV tanks. The temperature history data for Type I, II, and III tanks was almost nonexistent for years prior to 1975. Document reviews indicate that there might be additional useful data in the US Department of Energy, Richland Operations Office (DOE-RL) records in Seattle, WA, and these records need to be reviewed to extract data that might have been disregarded during previous reviews. Thermal stress analyses were conducted using different temperature distribution scenarios on Type IV tanks. Such studies could not be carried out for other tank types due to lack of temperature history data. The results from Type IV tank analyses indicate that factors such as temperature distribution in the tank waste and rate of rise in waste temperature have a significant impact on the thermal stresses in the tank structures. Overall, the conclusion that can drawn from the thermal stress analyses is that these studies should be carried out for all tank types during the detailed analysis phase with temperature values that are reasonably close to the typical temperature histories of the respective tank types. If and/or when additional waste temperature data is acquired for tank Type I, II, and III tanks, additional cases need to be considered as tank structural integrity is sensitive to thermal loads. A few case studies were also performed using Type IV-b models to comprehend the effects of excavation boundaries, change in soil stratigraphy (layer thickness and properties), and radial extent of soil in the finite element models. The result from the case studies indicates that the slight variation in soil stratigraphy has little effects on the tank sections force and moment demands under mechanical loads. The case study for excavation slope or backfill transition boundary indicated that inclusion of such boundary yields conservative demands in the wall region while demands at other locations remain unaffected. Hence this excavation slope will be modeled in the detailed analysis of SSTs

    Paraffin-enabled graphene transfer

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    The transfer process of as-grown graphene limits its electrical performance and reliability. Here, the authors develop a transfer approach using paraffin as a support layer and obtain wrinkle-reduced and clean large-area graphene retaining high mobility

    Detection of Sentinel Lymph Nodes in patients with Early Stage Cervical Cancer

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    The purpose of this study was to determine the feasibility of identifying the sentinel lymph nodes (SNs) as well as to evaluate factors that might influence the SN detection rate in patients with cervical cancer of the uterus. Eighty nine patients underwent intracervical injection of 1% isosulfan blue dye at the time of planned radical hysterectomy and lymphadenectomy between January 2003 and December 2003. With the visual detection of lymph nodes that stained blue, SNs were identified and removed separately. Then all patients underwent complete pelvic lymph node dissection and/or para-aortic lymph node dissection. SNs were identified in 51 of 89 (57.3%) patients. The most common site for SN detection was the external iliac area. Metastatic nodes were detected in 21 of 89 (23.5%) patients. One false negative SN was obtained. Successful SN detection was more likely in patients younger than 50 yr (p=0.02) and with a history of preoperative conization (p=0.05). However, stage, histological type, surgical procedure and neoadjuvant chemotherapy showed no significant difference for SN detection rate. Therefore, the identification of SNs with isosulfan blue dye is feasible and safe. The SN detection rate was high in patients younger than 50 yr or with a history of preoperative conization
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