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Materials Sciences and Applications 2011年第2期2卷 81-86页

作者： Samuel J. Gana Nosa O. Egiebor ramble ankumah 不详

The corrosion behavior of 1020C carbon steel samples that had been subjected to oxidizing heat treatment at 550°C and 675°C were studied in sodium chloride electrolytes using a 3-electrode electrochemical impedance spectroscopy. Experimental data were used to evaluate the corrosion behavior of the samples while optical microscopy was employed to investigate the surface characteristics of the samples before and after aqueous corrosion. The results showed that while the sample treated at 550°C revealed an increasing corrosion rate with time, the sample treated at 675°C indicated a higher initial corrosion rate, but the rate declined gradually over the 4-day experimental period. Optical microscopy revealed significant formation of surface corrosion products on both heat treated samples, but the complex plane diagrams indicated significant capacitive behavior for the heat treated samples relative to the untreated samples.

关键词： Impedance Carbon Steel Corrosion Nyquist Diagrams Photomicrographs

Assessing the Effects of Solarization and Sodium Azide Amendments on Selected Soil Parameters, Enzyme Activities and Microbial Populations

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Journal of Environmental Protection 2013年第8期4卷 772-778页

作者： Anthony S. Kumi Victor Khan ramble O. ankumah Department of Agricultural and Environmental Sciences Tuskegee University Tuskegee USA George Washington Carver Agriculture Experiment Station College of Agriculture Environment and Nutrition Sciences Tuskegee University Tuskegee USA

Soil borne pathogens result in serious losses in yield of crops grown in the United States (US) and various parts of the world. One of the most effective chemicals used to control these pathogens was methyl bromide (CH3Br, MeBr), a pre-plant fumigant with a broad spectrum of activity. Sodium azide has been proposed in combination with solarization as a viable alternative to replace MeBr due to environmental concerns with respect to ozone depletion in the stratosphere and as a possible carcinogen. However, the possible impacts of sodium azide as a soil pollutant and its effect on soil biological processes have not been fully studied. In this study the effect of sodium azide used alone and in combination with solarization and mulching on selected soil enzyme activities (phosphomonoesterases, arylsulfatase and phosphodiesterase) were assessed. Responses of arylsulfatase and phosphodiesterase to solarization and mulching and azide treatment were found to be affected in the same way, suggesting a similar mode of action. Soil pH in control soils was significantly increased by azide application;however, in mulched soils, pH was decreased. The significant decrease in soil pH in mulched soils may be very important in explaining the increase in the acid phosphatase activity observed in mulched soils. Overall, solarization and sodium azide treatment significantly reduced both fungi and bacterial populations but the responses among the various treatments varied significantly.

关键词： Sodium Azide Solarization Methyl Bromide Soil Enzyme Activity Microbial Populations

CROPGRO-Soybean Model Calibration and Assessment of Soybean Yield Responses to Climate Change

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American Journal of Climate Change 2020年第3期9卷 297-316页

作者： Joseph E. Quansah Pauline Welikhe Gamal El Afandi Souleymane Fall Desmond Mortley ramble ankumah Department of Agricultural and Environmental Sciences Tuskegee University Tuskegee AL USA Agronomy Department Purdue University West Lafayette IN USA

Process-based crop simulation models are useful for simulating the impacts of climate change on crop yields. Currently, estimation of spatially calibrated soil parameters for crop models can be challenging, as it requires the availability of long-term and detailed input data from several sentinel sites. The use of aggregated regional data for model calibrations has been proposed but not been employed in regional climate change studies. The study: 1) employed the use of county-level data to estimate spatial soil parameters for the calibration of CROPGRO-Soybean model and 2) used the calibrated model, assimilated with future climate data, in assessing the impacts of climate change on soybean yields. The CROPGRO-Soybean model was calibrated using major agricultural soil types, crop yield and current climate data at county level, for selected counties in Alabama for the period 1981-2010. The calibrated model simulations were acceptable with performance indicators showing Root Mean Square Error percent of between 27 - 43 and Index of Agreement ranging from 0.51 to 0.76. Projected soybean yield decreased by an average of 29% and 23% in 2045, and 19% and 43% in 2075, under Representative Concentration Pathways 4.5 and 8.5, respectively. Results showed that late-maturing soybean cultivars were most resilient to heat, while late-maturing cultivators needed optimized irrigation to maintain appropriate soil moisture to sustain soybean yields. The CROPGRO-Soybean phenological and yield simulations suggested that the negative effects of increasing temperatures could be counterbalanced by increasing rainfall, optimized irrigation, and cultivating late-maturing soybean cultivars.

关键词： Climate Change CROPGRO-Soybean Model Crop Yield Soil Parameters

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新浪也挂马——手把手教你新浪博客挂马

黑客防线 2007年第3期 39-40页

作者： ramble

大家好，我是ramble，偶然发现了新浪的一个安全问题，也许新浪不认为是漏洞吧，不过如果被有心人利用，危害可不小啊!故写了本文，望大家警惕!此稿为本人处女稿，请大家多多捧场，谢谢!（哎哟，谁扔的鸡蛋!）

关键词：新浪博客把手安全问题

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苯教天文历算传承研究

宗教学研究 2020年第4期 169-174页

作者： [英]查尔斯·兰博拉毛吉(译) 法国巴黎高等研究实践学院(EPHE) 西藏大学中国藏学研究所

本文节译部分主要讲述了两方面内容:第一,敦煌大事年表中的纪年方式(包括作为典型个案的唐蕃会盟碑上的纪年)、萨迦历的编制特点、时轮历的兴起及藏人对待时轮历误差的态度及解释思维等,反映了藏历的不断变更和修正,都与不同阶段的宗教... 详细信息

本文节译部分主要讲述了两方面内容:第一,敦煌大事年表中的纪年方式(包括作为典型个案的唐蕃会盟碑上的纪年)、萨迦历的编制特点、时轮历的兴起及藏人对待时轮历误差的态度及解释思维等,反映了藏历的不断变更和修正,都与不同阶段的宗教、文化影响息息相关,表现出其微妙的政治特征;第二,以旦增南达的教育轨迹为例详述藏历在苯教中传承的教育模式、课程内容、革新内容,说明佛、苯在相互撷取对方作品时巧妙地自圆其说,苯教甚至主张"孔泽"360算法的根本来自时轮续。

关键词：苯教天文历算教育传承政治宗教