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41.
Jaakko Heikkinen Irina Kurganova Valentin Lopes de Gerenyu Taru Palosuo Kristiina Regina 《Nutrient Cycling in Agroecosystems》2014,98(1):97-106
The collapse of Soviet Union in early 1990s led to abandonment of large area of arable land which is assumed to act as a carbon (C) sink. We studied the ability of two dynamic soil C models (Yasso07 and RothC) to predict changes in soil C content after cropland abandonment. The performance of the models was compared using the results of a long-term experiment in Pushchino, Moscow region (54°50′N, 37°35′E) in Russia. The experiment was divided in four combinations of fertilizer or mowing treatments on former cropland soil. The soil C content was determined in the year of establishment (1980) and thereafter in 1999 and 2004. The soil C stocks increased by about 1.5- to 1.8-fold during the study period. Both models predicted the overall change in soil C relatively well (modelling efficiency of Yasso07 and RothC were 0.60 and 0.73, respectively). According to the models, the soil gained on average 140–150 g C m?2 year?1 during the first 5 years after conversion of cropland to grassland. The C sequestration rate decreased to 40–50 g C m?2 year?1 after 20 years of land use change. The sequestration rates estimated in this study are comparable to the rates observed in other studies. 相似文献
42.
Zaharah Allah Bukhsh Irina Stipanovic Giel Klanker Alan O’ Connor Andre G. Doree 《Structure and Infrastructure Engineering》2019,15(7):872-885
Bridge infrastructure managers are facing multiple challenges to improve the availability and serviceability of ageing infrastructure, while the maintenance planning is constrained by budget restrictions. Many research efforts are ongoing, for the last few decades, ranging from development of bridge management system, decision support tools, optimisation models, life cycle cost analysis, etc. Since transport infrastructures are deeply embedded in society, they are not only subject to technical requirements, but are required to meet the requirements of societal and economic developments. Therefore, bridge maintenance planning should accommodate multiple performance goals which need to be quantified by various performance indicators. In this paper, an application of Multi-Attribute Utility Theory (MAUT) for bridge maintenance planning is illustrated with a case study of bridges from the Netherlands road network. MAUT seeks to optimise multiple objectives by suggesting a trade-off among them and finally assigns a ranking to the considered bridges. Moreover, utility functions of MAUT appropriately account for the involved uncertainty and risk attitude of infrastructure managers. The main contribution of this study is in presenting a proof-of-concept on how MAUT provides a systematic approach to improve the decision-making of maintenance planning by making use of available data, accommodating multiple performance goals, their uncertainty, and preferences of infrastructure managers. 相似文献
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44.
Mihaela Habeanu Agnès Thomas Esperanza Bispo Mylène Gobert Dominique Gruffat Denys Durand Dominique Bauchart 《Meat science》2014
The effects of extruded linseed and rapeseed on lipids and FA composition of total, polar and neutral lipids of longissimus thoracis (LT) and semitendinosus (ST) muscles were investigated in 21 Normand cull cows. Animals were assigned in a 100d finishing period to straw (30%) and concentrate (70%) based (C) or the same diet supplemented with linseed (L) or with rapeseed (66%) plus linseed (33%) (RL). Beef polar and neutral lipids were purified by liquid chromatography and their FA analysed by GLC. Trans and cis 18:1, purified by HPLC from total FA methyl esters, were analysed by GLC–MS. L and LR diets did not increase beef lipid deposition, but had modified FA composition of both LT and ST muscles in favouring deposition of 18:3n-3 and 9cis,11tr 18:2 (CLA), mainly to the detriment of 18:1?9 cis (neutral lipids) and 18:2n-6 (polar lipids). However, they did not favour deposition of LC n-3 PUFA in the two muscles, but had increased deposition of trans 18:1 significantly, especially of ?13tr to ?16tr isoforms to the detriment of ?10tr 18:1 (L diet) and of ?11tr 18:1 (RL diet). 相似文献
45.
当前俄罗斯正在进行立法改革以实现治理体系现代化,其中改革的重点是国家管理体系中的劳动保护、工业安全和突发事件的应急处理。过去的立法体系侧重于对受伤员工提供健康补偿和医疗救护,而新的立法体系则以预防为主,以期通过建立完善的风险管理机制和运行规则,提高安全生产水平、普及安全文化教育,保障员工的生命安全。新标准强调企业必须进行职业风险评估,并将职业风险评估纳入企业工作管理体系。论文以采金业为例,选取伊尔库茨克州波戴波区金矿露天采场为研究案例,探讨了现代化职业风险评估的方法,明确了职业风险评估首先要进行危害鉴别,编制了风险源管理档案清单。采用实测员工风险因素的“记分法”和数学模拟“矩阵法”完成了伊尔库茨克州波戴波区金矿露天采场主要职业的风险评估。研究表明: 在钻井爆破作业场所,由碎石的喷射、粉尘的排放和噪声效应引起的危险为不可接受风险,通过实施安全生产制度(即遵守安全标准和技术要求、为工人提供防护装备),可将高风险和不可接受风险化解为可接受风险;阐述了高风险职业,编制了风险手册,提出了改善工作条件的首要措施是消除影响爆破手和钻机操作员的有害因素,并为员工提供能更有效预防噪音和振动的个人防护用品。 相似文献
46.
47.
Iana A. Minich Oleg I. Silyukov Liliia D. Kulish Irina A. Zvereva 《Ceramics International》2019,45(2):2704-2709
A protonated form of the n?=?4 layered bismuth containing perovskite-like titanate K2.5Bi2.5Ti4O13 belonging to Ruddlesden-Popper phases was prepared via ion exchange reaction of interlayer K+ with protons. Its composition was investigated by TG ICP and EDX analysis was found to be H2K0.5Bi2.5Ti4O13·H2O. The thermal behavior of the obtained phase was investigated by STA coupled with mass-spectrometry, the structural changes, happening with the sample during heating, were examined by XRD. It was shown that the as-prepared hydrated phase undergoes two-stage dehydration at low temperatures (up to 160?°C). The further heating leads to the gradual decomposition and crystallization of new phases, notably Bi2Ti2O7, Bi4Ti3O12 and Bi2Ti4O11. The morphology of the as-prepared sample and samples after heat treatment was examined using SEM. 相似文献
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49.
Flaxseed extracts obtained by microwave-assisted extraction (MAE) were cleaned of leftover salts from hydrolysis by solid phase extraction (SPE). The SPE set up was affordable, non-automated and vacuum-driven. The recovery patterns of secoisolariciresinol diglucoside (SDG), p-coumaric acid glucoside (PCouAG), and ferulic acid glucoside (FerAG) were modeled in two stages using regression procedures (p < 0.05). At stage one, the recovery patterns were predicted as a function of SPE eluent concentration in ethanol (10–50%). At stage two, the accuracy of the predictions was increased by enlarging the SPE eluent regressor's range (0–100% ethanol in water) and arranging the solvent system into three practical elution groups. The groups 1, 2 and 3 reflected the major loss, the major recovery and the minor loss of SDG, respectively. Second degree polynomial regression models were fitted for accurately predicting the recoveries of compounds. Microwave-assisted extracts obtained from 0.6 and 1.5 g defatted flaxseed meal were purified; the total SDG recoveries from the SPE funnel were 97.8 and 99.8%; and the SDG amounts obtained were 8.54 and 20 mg, respectively. The HPLC analysis of eluates pooled into practical groups allows for significant reductions in HPLC analysis time and solvent consumption which could have a positive impact on future purification studies. The results of this study allow for designing simplified, efficient and economical pilot scale studies for the purification of SDG from flaxseed extracts. 相似文献
50.
Monica Simion Mihaela KuskoIuliana Mihalache Adina Brăgaru 《Materials Science and Engineering: B》2013,178(19):1268-1274
Due to the high surface-to-volume ratio (hundreds of m2/cm3) porous silicon became during the last years a good candidate material as substrate for biosensor application. Moreover, the versatility of surface chemistry allows different functionalization approaches and large number of molecules to be captured on well-defined areas. This paper reports a dual detection method for protein recognition processes developed on different nanostructured porous silicon (PS) substrates, based on using two complementary spectroscopic techniques: fluorescence and electrochemical impedance. The structures were tested for biomolecular recognition – biotin–strepavidin couples – in order to achieve an optimum surface for protein's immobilizations. Comparative analyses of the attachment degree and preservation of the biomolecules activity on the porous silicon surfaces and silicon slides are also described. 相似文献