118 research outputs found
ENVIRONMENTAL AND ECONOMIC EFFICIENCY OF FUEL AND START GAS HEATERS
The paper presents the possibility of resource-saving for the fuel and starting gas heater, use of the gas transmission system at the facility. Reserves have been identified that allow the installation of heat-generating installations of lower capacity in order to save the enterprise’s money at the stage of purchasing equipment. Energy-efficient measures for a gas preheater are proposed, allowing to reduce the consumption of natural gas and reduce emissions of pollutant emissions into the atmosphere.В работе показана возможность ресурсосбережения на подогревателях топливного и пускового газа (ПТПГ), установленных на объектах газотранспортной системы. Выявлены резервы, позволяющие устанавливать теплогенерирующие установки меньшей мощности в целях экономии денежных средств предприятия на этапе закупки оборудования. Предложены энергоэффективные мероприятия для ПТПГ, позволяющие сократить потребление природного газа и уменьшить выбросы загрязняющих веществ в атмосферу
Thermal and electrical conductivity of iron at Earth's core conditions
The Earth acts as a gigantic heat engine driven by decay of radiogenic
isotopes and slow cooling, which gives rise to plate tectonics, volcanoes, and
mountain building. Another key product is the geomagnetic field, generated in
the liquid iron core by a dynamo running on heat released by cooling and
freezing to grow the solid inner core, and on chemical convection due to light
elements expelled from the liquid on freezing. The power supplied to the
geodynamo, measured by the heat-flux across the core-mantle boundary (CMB),
places constraints on Earth's evolution. Estimates of CMB heat-flux depend on
properties of iron mixtures under the extreme pressure and temperature
conditions in the core, most critically on the thermal and electrical
conductivities. These quantities remain poorly known because of inherent
difficulties in experimentation and theory. Here we use density functional
theory to compute these conductivities in liquid iron mixtures at core
conditions from first principles- the first directly computed values that do
not rely on estimates based on extrapolations. The mixtures of Fe, O, S, and Si
are taken from earlier work and fit the seismologically-determined core density
and inner-core boundary density jump. We find both conductivities to be 2-3
times higher than estimates in current use. The changes are so large that core
thermal histories and power requirements must be reassessed. New estimates of
adiabatic heat-flux give 15-16 TW at the CMB, higher than present estimates of
CMB heat-flux based on mantle convection; the top of the core must be thermally
stratified and any convection in the upper core driven by chemical convection
against the adverse thermal buoyancy or lateral variations in CMB heat flow.
Power for the geodynamo is greatly restricted and future models of mantle
evolution must incorporate a high CMB heat-flux and explain recent formation of
the inner core.Comment: 11 pages including supplementary information, two figures. Scheduled
to appear in Nature, April 201
Analysis of the feasibility of reducing fuel consumption and carbon-dioxide emissions and obtaining carbon credits with the use of sverdlovskaya-oblast factories as an example
This article discusses aspects of improving the efficiency of heating and heat-treatment furnaces from the standpoint of the fuel savings that can be realized by the use of different methods to modernize such furnaces. © 2013 Springer Science+Business Media New York
Inspired by Sea Urchins: Warburg Effect Mediated Selectivity of Novel Synthetic Non-Glycoside 1,4-Naphthoquinone-6S-Glucose Conjugates in Prostate Cancer
The phenomenon of high sugar consumption by tumor cells is known as Warburg effect. It results from a high glycolysis rate, used by tumors as preferred metabolic pathway even in aerobic conditions. Targeting the Warburg effect to specifically deliver sugar conjugated cytotoxic compounds into tumor cells is a promising approach to create new selective drugs. We designed, synthesized, and analyzed a library of novel 6-S-(1,4-naphthoquinone-2-yl)-d-glucose chimera molecules (SABs)—novel sugar conjugates of 1,4-naphthoquinone analogs of the sea urchin pigments spinochromes, which have previously shown anticancer properties. A sulfur linker (thioether bond) was used to prevent potential hydrolysis by human glycoside-unspecific enzymes. The synthesized compounds exhibited a Warburg effect mediated selectivity to human prostate cancer cells (including highly drug-resistant cell lines). Mitochondria were identified as a primary cellular target of SABs. The mechanism of action included mitochondria membrane permeabilization, followed by ROS upregulation and release of cytotoxic mitochondrial proteins (AIF and cytochrome C) to the cytoplasm, which led to the consequent caspase-9 and -3 activation, PARP cleavage, and apoptosis-like cell death. These results enable us to further clinically develop these compounds for effective Warburg effect targeting
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