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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
351

THE LINKS BETWEEN GULF OF MEXICO SEAFLOOR CHARACTERISTICS AND PETROLEUM HYDROCARBONS FOLLOWING THE DEEPWATER HORIZON OIL SPILL

Schindler, Kimberly J. 01 January 2019 (has links)
The Gulf of Mexico (GoMx) is among the most productive regions for offshore oil and natural gas recovery. In 2010, the Deepwater Horizon (DWH) drilling rig exploded, burned for three days, sank, and released over 4 million barrels of oil in the subsequent 84 days before it was capped. Some oil was buoyant enough to float to the ocean surface, where some was removed via a myriad techniques. Importantly, a plume of oil remained suspended in the water column at approximately 1,100 m water depth, where it drove a marine snow event, and deposited large quantities of oil on the seafloor. The northern GoMx seafloor is complex and dynamic. Submarine canyons, mounds, channels, and salt domes dominate the seafloor along the continental slope surrounding the DWH well. Using high-resolution bathymetric data, variables derived to characterize the seafloor (water depth, distance, slope, and aspect), and spatial relationships between seafloor stations and the DWH well, relationships between concentrations, fluxes and inventories of polycyclic aromatic hydrocarbons, and other seafloor variables were hypothesized to be statistically significantly related. The most significant seafloor characteristic to predict distributions was water depth, followed by distance, relative aspect, and slope.
352

The response of symbiotic performance, growth and yield of chickpea (Cicer arietinum L. ) genotypes to phosphorus fertilizer rates and rhizobial inoculation

Muthabi, Anza 12 August 2020 (has links)
MSCAGR (Plant Production) / Department of Plant Production / Chickpea (Cicer arietinum L) is adapted to cool-seasons and its organs are of high nutritive value and serve as cheap sources of protein, especially in developing countries. Chickpea crop is mainly grown for human consumption, animal feed and for medicinal purposes. The introduction and promotion of chickpea to especially small-scale South African crop farmers has multiple objectives including the improvement of soil fertility. Small-scale farmer’s flounder to afford Nfertilizers, coupled with the challenges faced by programmes aimed at assisting them about soil fertility in their cropping fields that are still without enough N concentration to meet N demand. It is therefore important that other alternatives that can help improve the N status of soils be explored. The shoot δ13C is an indicator of WUE in C3 plants. However, shoot-WUE is affected by a variety of factors including genotypes, phosphorus fertilizer application and availability of native or introduced rhizobial bacteria. However, not much is known on whether application of phosphate fertilizer, seed inoculation with rhizobial strain affect the shoot C/N ratio of chickpea genotypes in South Africa. Therefore, field experiments were established at Thohoyandou and Syferkuil in Limpopo to assess the role of phosphorus fertilization and rhizobial inoculation on C assimilation, C/N ratio and shoot-WUE of chickpea genotypes. Field experiments were conducted during winter season in 2016 and 2017 (April to August). Treatments consisted of a factorial combination of two rates of phosphorus fertilizer (0 and 90 kg P ha-1 ), four desi chickpea genotypes (ACC#1, ACC#2, ACC#3 and ACC#5) and two rhizobial inoculation levels (bradyrhizobium strain and without rhizobial strain. In Thohoyandou, ACC#1 showed greater grain yield in 2016 and 2017. Which was associated with more branches and greater plant height. Furthermore, the interaction between genotypes, phosphorus fertilizer and rhizobial inoculation had significant effect on grain yield in 2016. ACC#1, 3 and 5 of chickpea genotypes fixed the most N compared to that of ACC#2. In addition, ACC#5 had the highest soil N-uptake in both seasons followed by ACC#3, while ACC#1 had the least value of soil N-uptake in both seasons. Phosphorus fertilizer application increased the fixation of N by 36.8% (P≤0.01), and similarly in soil N-uptake by difference of 59.9% compared to control in 2016. Furthermore, rhizobial inoculation increased N-fixed in 2016 and soil N-uptake in both seasons. ACC#5 had the highest N fixed at phosphorus-fertilized with bradyrhizobuim across two locations in both seasons. ACC#5 depended more on soil N-uptake than fixing its own N as compared to ACC#1. N fixation differed across seasons; however, ACC#3 had greater N-fixed in both locations. Moreover, chickpea genotype that fixed more N had least δ15N. This finding indicates that N fixation is exhibited by the genotypes that depend less on δ15N, because N2 fixation is inhibited by high soil N concentration or δ15N. Furthermore, ACC#2 and ACC#3 had greater δ13C at Thohoyandou in 2017; chickpea genotypes had significant effect on δ13C at P≤0.05 at Thohoyandou, 2016. The results showed that ACC#1 with phosphorus fertilizer application and no bradyrhizobium strain showed greater δ13C. Also, δ13C increased with a decrease in N-fixed (r=.1000), this indicates that there was a functional relationship between plant WUE and N fixation in chickpea, probably because improved water use in legumes supports N fixation. / NRF
353

Manganese Accumulation and its Control in Chlorinated Drinking Water Distribution System / 塩素処理された水道配水システムにおけるマンガンの蓄積性とその制御

Zhou, Xinyi 24 November 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22841号 / 工博第4781号 / 新制||工||1748(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 伊藤 禎彦, 教授 米田 稔, 准教授 越後 信哉 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
354

Capital Accumulation and the Labor Share of Income

Broman, Julius January 2021 (has links)
This paper estimates the effects of capital accumulation on industry labor shares by taking account of capital heterogeneity. Using a cross-country, cross-industry dataset covering 15 European countries over 38 industries, I take advantage of a detailed breakdown of the capital stock distinguishing between physical, ICT and intangible assets. The results suggest that, over the 1995-2015 period, capital accumulation has not been a driving force of declining labor shares - if anything the opposite. Performing a cross-section regression analysis on the relationship between long differences in capital intensities and industry labor shares, I find that accumulation of physical capital in general, and Machinery & Equipment in particular, are the only asset types showing a statistically significant correlation with the labor share, suggesting a positive association. In contrast to previous research, I do not document a negative relationship between ICT capital and labor shares. I do, however, find evidence suggesting that it might be investments in Software & Databases that explain these earlier findings.
355

Reversible assembly and amyloidogenesis of the staphylococcal biofilm protein, Aap

Yarawsky, Alexander E. 14 October 2019 (has links)
No description available.
356

Satellite Radar and Laser Altimetry for Monitoring of Lake Water Level and Snow Accumulation in Arctic Regions

Shu, Song 18 October 2019 (has links)
No description available.
357

Zbytková životnost pecí v petrochemickém průmyslu / Residual Service Lifetime of Furnaces in Petrochemical Industry

Horsák, Libor January 2018 (has links)
The objectives of this work is residual lifetime of heaters in petrochemical industry. There is no comprehensive publication about this theme. This paper lists and describes the most of main phenomena that has to be taken into account in the process of determination of residual lifetime. This paper focuses on creep damage of a real heater based on deformation measurement. It describes some heater failures that could cause unplanned operation interruption however, appropriate intervention made possible safe heater operation until planned heater shutdown. No compact method is given how to determine heater residual lifetime, but a direction is given how a complex method of residual lifetime assessment of refinery heaters could be created.
358

Crisis, New Imperialisms, and Accumulation by Dispossession: The Case of the Pakistan Railways

Khan, Sher Ali 08 1900 (has links)
My research examines the three interrelated concepts of crisis; new imperialisms, spatial-temporal fix and accumulation by dispossession (ABD) stemming from the work of David Harvey as a way to understand the contested history of the Pakistan Railways. For the first thirty odd years after Pakistan's inception in 1947, the railways, a state-owned institution, was the primary mode of transport for the public, cargo, and workers. Alongside basic infrastructure, the railways had a vast network of hospitals, schools, workers' colonies and an array of physical infrastructure connected to production, operations and other aspects of the economy. The systematic ransack and decline of the Pakistan Railways reached its peak in 2010. Despite several attempts throughout the 1990s by successive democratic and military-led governments backed by the IMF/World Bank in 2015, it was announced that Pakistan railways would be revived under the banner of the 46 billion dollar China Pakistan Economic Corridor (CPEC) as part of the changing geopolitical context of growing regional connectivity and new Chinese imperialism. By examining the processes that underlie ABD, such as spatial-temporal fix, the following research shows that these processes not only reflect a shift of resources away from the public domain, but in Pakistan also entailed the transformation of the railways from a utilitarian welfare organization to an entity that facilitates looting, unbundling, and dispossession of shared resources and infrastructure.
359

Long-term Sediment Response Under Repetitive Mechanical and Environmental Loadings

Cha, Wonjun 06 1900 (has links)
Geostructures experience repetitive load cycles, which gradually affect their long-term performance. This thesis explores the long-term response of soils subjected to mechanical load-unload, heat-cool, freeze-thaw, and atmospheric pressure oscillations. The research methodology involves new instrumented cells (oedometer, temperature-controlled triaxial chamber, and pressure-controlled drying chamber), various geophysical monitoring methods (X-ray micro-CT, NMR, S-wave, and EM-waves), and simulations using discrete element modeling. Results show that soils subjected to repetitive mechanical or environmental loading experience shear and volumetric strain accumulation and changes in saturation (during barometric pressure cycles). In all cases, soils evolve towards an asymptotic terminal void ratio; the change in void ratio is pronounced when the soil exhibits grain-displacive ice formation during freeze-thaw cycles. The initial stress obliquity defines the shear strain response, which may be either shakedown -at low stress obliquity-, or ceaseless shear strain accumulation in ratcheting mode when the maximum stress obliquity approaches failure conditions. Finally, we provide simple engineering guidelines to estimate the long-term behavior of soils subjected to repetitive mechanical or environmental loading.
360

Model akumulace velkých objemů energie / Model of Bulk Energy Accumulation

Radil, Lukáš January 2008 (has links)
The purpose of this pursuit is to introduce the reader about the questions of the accumulation of the electric energy and to outline possibilities of its design and what instruments is possible to get it. The other purpose is to inscribe possibilities of today´s attachment of dispersive sources to the net from the sight of the ERU, eventually from the sight of the UCTE. This persuit describes the posibility of the accumulation of adequate dimensions from renewable resources, the modern trends in this area and the prediction of future progress. The two most proper types of the energy accumulation are chosen by the following process with regarding to the optimal resolution of the given questions. The general balance will be ana-lysed by the comparison of their basic parameters. The other point of this pursuit is to try to realize a small model of the accumulation through the hydrogen´s cycle, it comes to that we can develop the efficiency and influence by the help of the electrolyzer and the metalhydride reservoir is realized energy of accumulation . In the conclusion of this pursuit is the appreciation of the whole project with the view of partly economical and especially with the view of the prospective usage into the electric grid

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