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排序方式: 共有1320条查询结果,搜索用时 15 毫秒
1.
Fabíola Azanha de Carvalho Amanda Aleixo Moreira André Luiz Martinez de Oliveira Fabio Yamashita 《应用聚合物科学杂志》2021,138(28):50667
Neat poly (lactic acid) (PLA) and PLA/cassava bagasse (CB) composites were used to produce seedling tubes by extrusion and injection molding. The tubes were buried in simulated soil, and their biodegradation was investigated by weight loss, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). After 180 days, the composites' biodegradation was higher than neat PLA material, and the higher the CB content, the higher the biodegradation, which caused fissures and voids in the material. The biodegradation of PLA/CB composites increased the phosphorus content in the soil after 180 days. Composites of PLA with CB, an abundant agro-industrial residue in Brazil, are promising because they can reduce the environmental impact due to CB's proper destination, and the composites' costs and biodegradation are faster than pure PLA material. Both the faster biodegradation of the tube and the higher P content are advantageous for seedling tubes. 相似文献
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Amanda Alliband Daniel W. Lenz Laura E. Stevenson Travis Whitmer Rex Cash Dennis Burns Sarah Hall William T.K. Stevenson 《Progress in Organic Coatings》2008
A model has been proposed to explain the failure of the original BMS10-39 epoxy paint on upper vertical surfaces in B-52 fuel tanks. The model involves interaction of the paint with DIEGME, a fuel system ice inhibitor (FSII) in jet fuel, that is distilled from the liquid fuel. In this communication, distillation experiments used to support the model are refined to better match the mass transfer of vapor from fuel in a B-52 fuel tank at close to room temperature. The interaction of these lower temperature distillates with the paint affirms the earlier model. On the basis of these experiments it is proposed that paint failure may be controlled or eliminated by reducing the level of DIEGME in the fuel. Proposed changes in military jet fuel composition are detailed. 相似文献
5.
RE Kelly GS Hartman PB Embree G Sharp JF Artusio 《Canadian Metallurgical Quarterly》1993,77(3):540-543
We studied the effect of premedication (1 microgram/kg fentanyl and 0.04 mg/kg midazolam 5 min before induction of anesthesia) on airway reactivity and hemodynamic stability during inhaled induction using desflurane in 10 ambulatory surgical patients. Eight patients who were anesthetized without premedication served as the controls. Induction and emergence were rapid and unaffected by premedication. End-tidal and inspired concentrations of desflurane at loss of consciousness were significantly reduced by premedication (10.1% end-tidal/14.1% inspired, no premedication, vs. 5.3% end-tidal/8.9% inspired, premedication). Airway irritability was markedly attenuated by premedication (100% no premedication versus 30% premedicated), as was apnea (37.5% no premedication versus 0% premedicated). We observed an increase in mean arterial blood pressure and heart rate after loss of consciousness (mean arterial pressure 103 vs 121 mm Hg, heart rate 73 vs 100 bpm) in the unpremedicated patients, whereas both groups demonstrated a decrease in mean arterial blood pressure with no change in heart rate when baseline values were compared to those at incision (103 vs 74 mm Hg, no premedication, 99 vs 81 mm Hg premedicated). Patient acceptability was satisfactory and unchanged by premedication. We recommend the use of such premedication when desflurane is used during the induction of anesthesia. 相似文献
6.
Amanda LaCoste Karen M. Schaich David Zumbrunnen Kit L. Yam 《Packaging Technology and Science》2005,18(2):77-87
Researchers from Rutgers University and Clemson University have collaborated to develop a concept of using smart blending to generate functional packaging films for the controlled release of active compounds such as antimicrobials, antioxidants and flavour compounds to extend the shelf‐life of food. In this paper, literature results are reviewed to justify the significance of controlled release packaging (CRP) and the research gaps for further development are identified. A major research gap is the lack of packaging materials that can provide the release of active compounds at rates suitable for a wide range of food packaging applications. Smart blending is a promising technology for bridging this research gap. To fully realize the potentials of smart blending, a systematic approach for developing CRP using smart blending is also presented. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
7.
Kreppner Jana M.; Rutter Michael; Beckett Celia; Castle Jenny; Colvert Emma; Groothues Christine; Hawkins Amanda; O'Connor Thomas G.; Stevens Suzanne; Sonuga-Barke Edmund J. S. 《Canadian Metallurgical Quarterly》2007,43(4):931
Longitudinal analyses on normal versus impaired functioning across 7 domains were conducted in children who had experienced profound institutional deprivation up to the age of 42 months and were adopted from Romania into U.K. families. Comparisons were made with noninstitutionalized children adopted from Romania and with nondeprived within-U.K. adoptees placed before the age of 6 months. Specifically, the validity of the assessment, the degree of continuity and change in levels of functioning from 6 to 11 years, and the factors in the pre- and postadoption environment accounting for heterogeneity in outcome were examined. Pervasive impairment was significantly raised in children experiencing institutional deprivation for ≥6 months of life, with a minority within this group showing no impairment. There was no additional significant effect of duration of deprivation beyond the 6-month cutoff, and few other predictors explained outcome. The pattern of normality/impairment was mainly established by 6 years of age, with considerable continuity at the individual level between 6 and 11 years. The findings are discussed in terms of the possibility of a sensitive period for development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Burns John W.; Kubilus Amanda; Bruehl Stephen; Harden R. Norman; Lofland Kenneth 《Canadian Metallurgical Quarterly》2003,71(1):81
Changes in maladaptive cognitions may constitute therapeutic processes of multidisciplinary pain programs. A cross-lagged panel design was used to determine whether (a) early-treatment cognitive change predicted late-treatment outcome index change, but not vice versa; and (b) these effects remained significant with depression change controlled. Ninety chronic pain patients, in a 4-week multidisciplinary program, completed measures of catastrophizing, pain helplessness, depression, pain, interference, and activity level at pre-, mid-, and posttreatment. With depression changes controlled, early-treatment catastrophizing and pain helplessness changes predicted late-treatment outcome index changes, but not vice versa; early-treatment depression changes predicted late-treatment activity changes, but not vice versa. Findings advance understanding of pain treatment process and suggest that negative cognition changes may indeed affect improvements in treatment outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Joannie W. Chin Eric Byrd Ned Embree Jonathan Martin J. D. Tate 《Journal of Coatings Technology》2002,74(929):39-44
Laboratory ultraviolet (UV) chambers are widely used to obtain weathering data for a wide range of commercial polymer products
including coatings, textiles, elastomers, plastics, and polymeric composites. Although numerous improvements have been made
in the design of UV chambers over the last 80 years, the reproducibility of the exposure results from these chambers has remained
elusive. This lack of reproducibility is attributed to systematic errors in their design, operation, and control which prevent
direct comparisons of the performance of materials exposed in the same environment, comparisons of the performance of the
same material exposed in different laboratories, and the comparison of field and laboratory results. This paper describes
an innovative UV chamber design based on integrating sphere technology that greatly reduces the magnitude of these errors,
as well as provides additional experimental capabilities.
Presented at the 79th Annual Meeting of the Federation of Societies for Coatings Technology, on November 4–7, 2001, in Atlanta,
GA.
Building Materials Division. Gaithersburg, MD.
Freeport, TX. 相似文献
10.
Greer Robert A. Lee Kyungsun Fencl Amanda Sneegas Gretchen 《Water Resources Management》2021,35(11):3497-3511
Water Resources Management - Public–private partnerships (PPPs) have grown in popularity as a method to leverage private sector actors in the production of government services. With the... 相似文献