Amorphization kinetics under electron irradiation

A model is brought forward of the kinetics of amorphization occurring under electron irradiation. The model is based on consideration of the phase transformations controlled by the structural relaxation of small-scale unstable atomic configurations excited by electrons.Наведено модель кінетики аморфізації під електронним випромінюванням. Модель грунтується на розгляді фазових перетворень, які контролюються структурной релаксацієй дрібномасштабних нестабільних атомних конфігурацій, які збуджуються електронами.Приведена модель кинетики аморфизации под электронным облучением. Модель основывается на рассмотрении фазовых превращений, которые контролируются структурной релаксацией мелкомасштабных нестабильных атомных конфигураций, которые возбуждаются электронами

SINH KHOÁNG PERMI - TRIAS MIỀN BẮC VIỆT NAM

Permo-Triassic metalogeny of North Vietnam The Permo-Triassic period in North Vietnam has determined three ore complexes, formed in the different structures: 1/ Cu-Ni-(PGE) and Ti-Fe-V ore complex; 2/ gold-sulfide and 3/ tin-sulfide. The first complex consists of Cu-Ni-(PGE) mineralization associated with differentiated mafic-ultramafic intrusions of various volcano-plutonic types of the Song Da, Song Hien rift zones, and fold belts surrounding the Song Chay Dome. The Cu-Ni-PGE and Ti-Fe-V complexes, temporally corresponding to the two stages of plume magmatic activities: 260 Ma (Song Hien and Song Da) and 250 Ma (Phu Ngu-Lo Gam), similar to the associated ore occurrences of Emeishan LIP in Southwest of China (Limahe, Jang Baoshan, Panzhihua,...). Gold-sulfide ore complexes, including Au-As, Au-Sb, Sb-Hg-Au and Hg-Sb-(Au) types widespread in the Song Da and Song Hien rift zones as well as in Paleozoic Lo Gam and Quang Ninh folded structures. Within these structures, ore distribution in the form of ore nodes: Lang Vai, Lang Neo, Loc Shoa, Khe Chim ... Common features of these ore nodes are similar ore chemistry(Au, Sb, As, Hg) and zonation: Au-As → Au-Sb → As-Sb-Hg → Hg, as well transitional relations between different types of ore: Au-As and Au-Sb, Au-Sb and Sb-Hg (Lang Vai, Lang Neo ore nodes,...). Ages of ore formation of this complex range from 252-229 Ma, and spatial correlation with bimodal volcano - plutonic (basalt - rhyolite, rhyolite - basalt, granite - porphyry) as well as with small granite and gabbro - syenite intrusion, with age variation of about 247 -233 Ma

Superstripes and complexity in high-temperature superconductors

While for many years the lattice, electronic and magnetic complexity of high-temperature superconductors (HTS) has been considered responsible for hindering the search of the mechanism of HTS now the complexity of HTS is proposed to be essential for the quantum mechanism raising the superconducting critical temperature. The complexity is shown by the lattice heterogeneous architecture: a) heterostructures at atomic limit; b) electronic heterogeneity: multiple components in the normal phase; c) superconducting heterogeneity: multiple superconducting gaps in different points of the real space and of the momentum space. The complex phase separation forms an unconventional granular superconductor in a landscape of nanoscale superconducting striped droplets which is called the "superstripes" scenario. The interplay and competition between magnetic orbital charge and lattice fluctuations seems to be essential for the quantum mechanism that suppresses thermal decoherence effects at an optimum inhomogeneity.Comment: 20 pages, 3 figures; J. Supercon. Nov. Mag. 201

Composition of Fluids Responsible for Gold Mineralization in the Pechenga Structure-Imandra-Varzuga Greenstone Belt, Kola Peninsula, Russia.

This study presents the first fluid inclusion data from quartz of albite–carbonate–quartz altered rocks and metasomatic quartzite hosting gold mineralization in the Pechenga structure of the Pechenga– Imandra–Varzuga greenstone belt. A temperature of 275–370°C, pressure of 1.2–4.5 kbar, and the fluid composition of gold-bearing fluid are estimated by microthermometry, Raman spectroscopy, and LA-ICP-MS of individual fluid inclusions, as well as by bulk chemical analyses of fluid inclusions. In particular, the Au and Ag concentrations have been determined in fluid inclusions. It is shown that albite–carbonate–quartz altered rocks and metasomatic quartzite interacted with fluids of similar chemical composition but under different physicochemical conditions. It is concluded that the gold-bearing fluid in the Pechenga structure is similar to that of orogenic gold deposits

Energy and agrotechnical indicators in the testing of machine-tractor units with subsoiler

The present-day agriculture involves anthropogenic effects on the soil, including the compaction and over compaction of soil horizons at depths up to 1.2 m. The plowing of the soil with moldboard plows to a depth of 0.3 m results in the formation of a plow pan (hardpan), which hampers the development of plant roots; the optimum soil density for most agricultural crops is ? = 1.1-1.3 t/m3. There are supporters and opponents of deep subsoil plowing; only the plow horizon is the main object of studies. Chisel tools (subsoilers) have been studied on modernized models, which ensure the deep non-moldboard loosening to a depth of 0.30-0.45 m and more (down to 0.8 m) with the use of straight or slant shanks. Shank cultivators developed by the Siberian Research Institute of Mechanization and Electrification of Agriculture (SibIME), which penetrate to 0.30 m, were first used to control deflation. The American slant-shank subsoiler (Trade name, ‘Paraplow’) is the prototype of chisel implements. A range of tillage tools has been developed to form a ridged furrow bottom due to soil breakdown. Modernized tillage tools include breasts mounted on shanks for turning the upper (loosened) soil layer up to 0.20 m thick, as well as blades for cutting weeds, ridges, etc. Chisel modifications are mainly aimed at expanding their functional capabilities and decreasing the energy intensity of soil cultivation. The tests have confirmed the decrease of C, N, and humus losses; the improvement of the water and air conditions in the soil; the prevention of erosion; the improvement of tillage quality parameters; the increase of tractor aggregate output; and the saving of up to 25% of motor fuel