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The beach site is located in the utmost northeastern part of the Nevskaya Bay. A boulder dam is built on the western side, which, however, fails to protect the beach from the effects of waves that cause longshore sediment transport. The planned construction of transverse beach–retaining structures outlines in the “Water Sports Base in Primorsky District” initiative, mightchange the current situation. This study objective is to predict the evolution of the coastal contour resulting from the planned construction in the next few decades. A natural analogue of such an artificial structure could be a pocket beach located between two natural promontories. The sediment equilibrium at this study location includes three main components: volumes of erosion, accumulation and bypassing. The results include the computed wave patterns and the movement of sediment along the shoreline. The lateral sediment transport diminishes notably over time, driven by the alteration of the shoreline contour and the reduction in the angle between the wave equilibrium and the coastal resultant. The erosion and accumulation volumes increase over time, but their rates slow down. The shoreline displacement becomes more prominent over time; however, the rates of erosion differ from accumulation. The shoreline is moving particularly fast in the first years after construction, and then the process slows down gradually. The introduction of artificial beach protection structures in the 300th Anniversary Park of St. Petersburg will considerably reduce both the pace of beach erosion and the affected area. However, the erosion process will not be completely halted.

В статье рассматриваются вопросы создания, применения и возможного дальнейшего перспективного использования в конструкции космических аппаратов силовых приводов и механизмов, созданных на основе материалов с эффектом памяти формы. The article deals with the establishment, application and future prospective use of power drives and mechanisms in spacecraft structure, which are based on materials with shape-memory effect.

AbstractNanographene (NG) is a potential candidate for organic EC materials because of its large π‐conjugated system, chemical stability, absorption band covering the visible region, and tunable optical properties by postsynthetic modification. We show that NGs carrying redox‐active triphenylamine (TPA) units covalently linked to the NG edge function as EC materials in the NIR region. The hybrid materials can be obtained by the installation of TPA units onto the NG edge and display changes in the absorption spectrum in the NIR region extending to a wavelength of over 2000 nm upon one‐electron oxidation and reduction at low potentials (<1.1 V). Time‐dependent unrestricted density functional theory calculation of a model NG at the UB3LYP/6‐31G(d,p) level of theory suggests that a narrow energy gap between the basal plane and the oxidized TPA unit is responsible for the observed EC function in the NIR region.

Relativistic formulas for the deuteron electromagnetic form factors are calculated in the impulse approximation retaining terms to all orders in Q/sup 2//M/sup 2/ approx. = (v/c)/sup 2/. The formulas are given as double integrals over the deuteron wave functions in momentum space, and hence can be evaluated for any deuteron model. We evaluate these formulas numerically for 9 different deuteron models: Reid soft core, two Lomon-Feshbach models, three Holinde-Machleidt models, and three four-component relativistic models. All of the models give results for the A structure function considerably below the experimental results; the effect of the relativistic treatment is to reduce the size of A by a factor of 2 to 5 at Q/sup 2/ of 100 fm/sup -2/ over what it would be in the nonrelativistic approximation. We discuss briefly the role of exchange currents; the pair terms are included in our calculation in a completely consistent manner, but the explicit rho..pi gamma.. contributions need to be calculated relativistically. We discuss in some detail the sensitivity of our calculation to the almost unknown neutron electric form factor, observing that a G/sub E/n roughly twice G/sub E/p in the region of Q/sup 2/=100 fm/sup -2/ would enable us to fit themore » data even without any rho..pi gamma.. contributions. We discuss the high Q/sup 2/ limits of our formulas, obtaining the result that the form factor falls one power of Q/sup 2/ faster than that predicted by the dimensional-scaling-quark model. We also study the low Q/sup 2/ limits and give explicit formulas for the corrections to the deuteron magnetic and quadrupole moments.« less

Abstract Lean gasoline engines offer greater fuel economy than common stoichiometric gasoline engines. However, excess oxygen prevents the use of the current three-way catalyst (TWC) to control nitrogen oxide (NOX) emissions in lean exhaust. A passive SCR concept, introduced by General Motors Global RD however, the rich operation necessary for NH3 production results in a fuel consumption penalty. The fuel penalty can be minimized by adjusting spark timing to increase rich-phase engine out NOX emissions and, thereby, NH3 levels. Additionally, higher engine out NOX during engine load increase to simulate acceleration resulted in additional fuel savings. A 10% fuel consumption benefit was achieved with the passive SCR approach by optimizing rich air-fuel equivalence ratio and spark timing while also utilizing acceleration load conditions.

River deltas and estuaries are disproportionally-significant coastal landforms that are inhabited by nearly 600 M people globally. In recent history, rapid socio-economic development has dramatically changed many of the World's mega deltas, which have typically undergone agricultural intensification and expansion, land-use change, urbanization, water resources engineering and exploitation of natural resources. As a result, mega deltas have evolved into complex and potentially vulnerable socio-ecological systems with unique threats and coping capabilities. The goal of this research was to establish a holistic understanding of threats, resilience, and adaptation for four mega deltas of variable geography and levels of socio-economic development, namely the Mekong, Yellow River, Yangtze, and Rhine deltas. Compiling this kind of information is critical for managing and developing these complex coastal areas sustainably but is typically hindered by a lack of consistent quantitative data across the ecological, social and economic sectors. To overcome this limitation, we adopted a qualitative approach, where delta characteristics across all sectors were assessed through systematic expert surveys. This approach enabled us to generate a comparative assessment of threats, resilience, and resilience-strengthening adaptation across the four deltas. Our assessment provides novel insights into the various components that dominate the overall risk situation in each delta and, for the first time, illustrates how each of these components differ across the four mega deltas. As such, our findings can guide a more detailed, sector specific, risk assessment or assist in better targeting the implementation of risk mitigation and adaptation strategies.

The authors develop a long-term Japanese domestic refuse-fired power generation model which is capable of assessing the reverse-power-flow energy to the electric utility over a period of up to 20 years. The authors have sought to construct the model so that it can perform its assigned task with as simple a modelling system as possible. The model structure is fully documented and a brief summary of results is given. >

Developing an eco-friendly, flexible and recyclable micro-structured dry electrode for sustainable life is essential. In this work, we have developed irregular, micro-structured sandpaper coated with graphite powder as an electrode for developing a simple, low-cost, contact-separation mode graphite-coated sandpaper-based triboelectric nanogenerator (GS-TENG) as a self-powered device and biomechanical sensor. The as-fabricated GS-TENG is a dielectric-conductor model. It is made up of a bottom layer with polytetrafluoroethylene (PTFE) as a triboelectric layer, which is attached onto a graphite-coated sandpaper-based electrode and a top layer with aluminum as another triboelectric layer as well as an electrode. The forward and reverse open-circuit voltages reach upto ~33.8 V and ~36.62 V respectively, and the forward and reverse short-circuit currents are ~2.16 µA and ~2.17µA, respectively. The output generated by GS-TENG can power 120 blue light-emitting diodes connected in series, liquid crystal display and can charge commercial capacitors along with the rectifier circuit. The capacitor of 22 µF is charged upto 5 V and is sufficient to drive digital watch as wearable electronics. Moreover, the device can track signals generated by human motion, hence it scavenges biomechanical energy. Thus, GS-TENG facilitates large-scale fabrication and has potential for future applications in wearable and portable devices.