scholarly journals Features of formation of lacustrine mineral resources

2021 ◽  
Vol 22 (2) ◽  
pp. 225-233
Author(s):  
Andrey A. Rasskazov ◽  
Evgeniy S. Gorbatov ◽  
Alexander E. Kotelnikov

The conditions of the formation of nonmetallic and ore minerals in limnogenic structures are considered. It has been established that lakes are natural enriches of a wide range of useful components - silicate, carbonate, water-soluble, ore, organomineral. The most significant minerals of modern lakes, in addition to water, are: sapropel, diatomite, lime and mineral salts. Deposits of sand, clay, oil shale, oil and gas, coal, phosphorites, zeolites, evaporites, bauxites, ferromanganese, copper ores, placer minerals, and some rare and dispersed elements are associated with limnogenic complexes of different ages. It is shown that a greater variety of minerals of ancient lacustrine complexes compared to modern ones is associated both with variations of lacustrine lithogenesis in the past and with post-sedimentation transformations of sedimentary matter. In particular, epigenetic enrichment of ancient lacustrine complexes with ore components is noted. It was revealed that hydrocarbons and diatomites of lacustrine genesis are of a higher quality compared to similar minerals of marine genesis. It is noted that evolutionary changes in the processes of accumulation of limnogenic minerals have affected to the greatest degree biogenic and chemogenic components. An example of this is the progressive accumulation of caustobiolites and the sulfate evolution of evaporites in lacustrine structures during the Phanerozoic. An analysis of the genetic characteristics of lacustrine minerals makes it possible to develop new exploratory traits of a number of sedimentary deposits.

Author(s):  
Yu. I. Voitenko

The article continues the author’s series of works on the application of synergetic theory to understand and describe the processes and phenomena that accompany the search and development of mineral resources. The research results show that the synergetic theory is universal and allows to understand and describe a wide range of phenomena and processes that occur in geological exploration and mining: dynamic phenomena in mines (outbursts of rocks and coal), spontaneous сombustion of сoal in coal mines, emergency outbursts of oil and gas from exploration wells, destruction of high-pressure pipelines, geodynamic phenomena in quaternary deposits, sedimentary rocks, and in the geological structures of the crystalline basement. One of the signs of processes and phenomena that have a synergistic nature is the nonlinear nature of the system’s response to weak perturbations. Minor disturbances slightly change the structure of geological material, in some cases change the mechanical and physical properties of formation fiuids. This creates the conditions for disturbing the unstable equilibrium of the system at the bifurcation points and its transition to another equilibrium state with other thermodynamic parameters that characterize the new state of the system. Such transitions are characterized by kinetic and phase transitions. In particular, in the reservoir rock, in coal, micro- and macrocrack systems are formed and developed. The shape of dissipative structures is described using fractal theory. The duration of self-organization of dissipative structures and the transition of the system to a new equilibrium state depends on the type of dissipative structures, the properties of the environment in which they are formed, and the speed of physicochemical processes. The article considers the behavior of the system “well – rock formation” as an open thermodynamic system. The internal energy of the formation is compared with the energy of external explosive action from the well. Specific examples show that the behavior of such a system is subject to the laws of synergetics and as a result of weak action on the formation from the well there are significant nonlinear effects of productivity growth due to the internal energy of the formation. This energy is generated by reservoir and rock pressures.


Author(s):  
Hamid Hussain ◽  
Divya Juyal ◽  
Archana Dhyani

Microsponge and Nanosponge delivery System was originally developed for topical delivery of drugs can also be used for controlled oral delivery of drugs using water soluble and bioerodible polymers. Microsponge delivery system (MDS) can entrap wide range of drugs and then release them onto the skin over a time by difussion mechanism to the skin. It is a unique technology for the controlled release of topical agents and consists of nano or micro porous beads loaded with active agent and also use for oral delivery of drugs using bioerodible polymers.


Biomics ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 389-393
Author(s):  
D.V. Mitrofanov ◽  
N.V. Budnikova

The drone brood contains a large number of substances with antioxidant activity. These substances require stabilization and strict adherence to storage conditions. Among these substances are unique decenoic acids, the content of which is an indicator of the quality of drone brood and products based on it. The ability of drone brood to reduce the manifestations of oxidative stress is shown. There are dietary supplements for food and drugs based on drone brood, which are used for a wide range of diseases. Together with drone brood, chitosan-containing products, propolis, royal jelly can be used. They enrich the composition with their own biologically active substances and affect the preservation of the biologically active substances of the drone brood. Promising are the products containing, in addition to the drone brood, a chitin-chitosan-melanin complex from bees, propolis, royal jelly. The chitin-chitosan-melanin complex in the amount of 5% in the composition of the adsorbent practically does not affect the preservation of decenic acids, while in the amount of 2% and 10% it somewhat worsens. The acid-soluble and water-soluble chitosan of marine crustaceans significantly worsens the preservation of decenoic acids in the product. Drone brood with royal jelly demonstrates a rather high content of decenoic acids. When propolis is introduced into the composition of the product, the content of decenoic acids increases according to the content of propolis.


Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 555
Author(s):  
Ji-Hyoun Kang ◽  
Dae-Am Yi ◽  
Alexander V. Kuprin ◽  
Chang-Do Han ◽  
Yeon-Jae Bae

The longhorn beetle, Callipogon (Eoxenus) relictus Semenov, is the only remnant species found in the Palearctic region, while all other Callipogon species are distributed mainly in Central America and partly in South America. This species has been placed in the first category (as ‘critically endangered’) of the Red Data Book in Russia and designated as one of the top-priority target species among all endangered invertebrate species for restoration in South Korea since 2006. Although its restricted distribution in Northeast Asia with a high conservational value has been highlighted, genetic features of C. relictus from different geographic regions remain unexplored. We first investigated the level of genetic diversity and phylogeographic patterns of C. relictus to evaluate the current conservational status and the feasibility of the implementation of a restoration program. The average genetic divergence of mitochondrial gene COI based on Kimura-2-parameter distance among the four regions in Russia, China, North Korea, and South Korea was 2.2%, which lies within the range of intraspecific levels. However, two separate clades with 3.8% divergence were identified, despite no geographical clustering of haplotypes. The linear pattern of the haplotype network with a high level of haplotype and nucleotide diversities suggests that the wide range of currently fragmented populations might be the remnant of genetically diverse populations in the past. This study will provide crucial information on the genetic characteristics and phylogeographic history of C. relictus, which will help to establish conservation strategies for this cherished insect species in Northeast Asia.


2020 ◽  
Vol 9 (1) ◽  
pp. 1118-1136
Author(s):  
Zhenjia Huang ◽  
Gary Chi-Pong Tsui ◽  
Yu Deng ◽  
Chak-Yin Tang

AbstractMicro/nano-fabrication technology via two-photon polymerization (TPP) nanolithography is a powerful and useful manufacturing tool that is capable of generating two dimensional (2D) to three dimensional (3D) arbitrary micro/nano-structures of various materials with a high spatial resolution. This technology has received tremendous interest in cell and tissue engineering and medical microdevices because of its remarkable fabrication capability for sophisticated structures from macro- to nano-scale, which are difficult to be achieved by traditional methods with limited microarchitecture controllability. To fabricate precisely designed 3D micro/nano-structures for biomedical applications via TPP nanolithography, the use of photoinitiators (PIs) and photoresists needs to be considered comprehensively and systematically. In this review, widely used commercially available PIs are first discussed, followed by elucidating synthesis strategies of water-soluble initiators for biomedical applications. In addition to the conventional photoresists, the distinctive properties of customized stimulus-responsive photoresists are discussed. Finally, current limitations and challenges in the material and fabrication aspects and an outlook for future prospects of TPP for biomedical applications based on different biocompatible photosensitive composites are discussed comprehensively. In all, this review provides a basic understanding of TPP technology and important roles of PIs and photoresists for fabricating high-precision stimulus-responsive micro/nano-structures for a wide range of biomedical applications.


1970 ◽  
Vol 24 (3) ◽  
pp. 479-502 ◽  
Author(s):  
R. L. Friedheim ◽  
J. B. Kadane

International arrangements for the uses of the ocean have been the subject of long debate within the United Nations since a speech made by Ambassador Arvid Pardo of Malta before the General Assembly in 1967. Issues in question include the method of delimiting the outer edge of the legal continental shelf; the spectrum of ocean arms control possibilities; proposals to create a declaration of principles governing the exploration for, and the exploitation of, seabed mineral resources with the promise that exploitation take place only if it “benefits mankind as a whole,” especially the developing states; and consideration of schemes to create international machinery to regulate, license, or own the resources of the seabed and subsoil. The discussions and debates began in the First (Political and Security) Committee of the 22nd General Assembly and proceeded through an ad hoc committee to the 23rd and 24th assembly plenary sessions. The creation of a permanent committee on the seabed as a part of the General Assembly's machinery attests to the importance members of the United Nations attribute to ocean problems. Having established the committee, they will be faced soon with the necessity of reaching decisions. The 24th General Assembly, for example, passed a resolution requesting the Secretary-General to ascertain members' attitudes on the convening of a new international conference to deal with a wide range of law of the sea problems.


1998 ◽  
Vol 550 ◽  
Author(s):  
V.P. Shastri ◽  
I. Martin ◽  
R. Langer

AbstractPorous polymeric media are used in several applications such as solid supports for separations and catalysis, as well as biomedical applications such as vascular grafts and wound dressings. We have developed a novel versatile process to produce polymeric cellular solids. This process which is based on a phase extraction-co-polymer precipitation is applicable to a wide range of polymer systems including water soluble polymers. It is capable of yielding polymer foams of high porosity (> 90%) and excellent mechanical characteristics in a very short time (less than 2 hours) without limitations in foam thickness. Polymer foam with such characteristics have great utility in tissue engineering applications. We have successfully explored polymer foams of biocompatible polymers produced by the presented approach for bone and cartilage engineering using bone marrow stromal cells.


2020 ◽  
pp. 42-45
Author(s):  
J.A. Kerimov ◽  

The implementation of plastic details in various constructions enables to reduce the prime cost and labor intensity of machine and device manufacturing, decrease the weight of design and improve their quality and reliability at the same time. The studies were carried out with the aim of labor productivity increase and substitution of colored and black metals with plastic masses. For this purpose, the details with certain characteristics were selected for further implementation of developed technological process in oil-gas industry. The paper investigates the impact of cylinder and compression mold temperature on the quality parameters (shrinkage and hardness) of plastic details in oil-field equipment. The accessible boundaries of quality indicators of the details operated in the equipment of exploration, drilling and exploitation of oil and gas industry are studied in a wide range of mode parameters. The mathematic dependences between quality parameters (shrinkage and hardness) of the details on casting temperature are specified.


2021 ◽  
Author(s):  
Nouf AlJabri ◽  
Nan Shi

Abstract Nanoemulsions (NEs) are kinetically stable emulsions with droplet size on the order of 100 nm. Many unique properties of NEs, such as stability and rheology, have attracted considerable attention in the oil industry. Here, we review applications and studies of NEs for major upstream operations, highlighting useful properties of NEs, synthesis to render these properties, and techniques to characterize them. We identify specific challenges associated with large-scale applications of NEs and directions for future studies. We first summarize useful and unique properties of NEs, mostly arising from the small droplet size. Then, we compare different methods to prepare NEs based on the magnitude of input energy, i.e., low-energy and high-energy methods. In addition, we review techniques to characterize properties of NEs, such as droplet size, volume fraction of the dispersed phase, and viscosity. Furthermore, we discuss specific applications of NEs in four areas of upstream operations, i.e., enhanced oil recovery, drilling/completion, flow assurance, and stimulation. Finally, we identify challenges to economically tailor NEs with desired properties for large-scale upstream applications and propose possible solutions to some of these challenges. NEs are kinetically stable due to their small droplet size (submicron to 100 nm). Within this size range, the rate of major destabilizing mechanisms, such as coalescence, flocculation, and Ostwald ripening, is considerably slowed down. In addition, small droplet size yields large surface-to-volume ratio, optical transparency, high diffusivity, and controllable rheology. Similar to applications in other fields (food industry, pharmaceuticals, cosmetics, etc.), the oil and gas industry can also benefit from these useful properties of NEs. Proposed functions of NEs include delivering chemicals, conditioning wellbore/reservoir conditions, and improve chemical compatibility. Therefore, we envision NEs as a versatile technology that can be applied in a variety of upstream operations. Upstream operations often target a wide range of physical and chemical conditions and are operated at different time scales. More importantly, these operations typically consume a large amount of materials. These facts not only suggest efforts to rationally engineer properties of NEs in upstream applications, but also manifest the importance to economically optimize such efforts for large-scale operations. We summarize studies and applications of NEs in upstream operations in the oil and gas industry. We review useful properties of NEs that benefit upstream applications as well as techniques to synthesize and characterize NEs. More importantly, we identify challenges and opportunities in engineering NEs for large-scale operations in different upstream applications. This work not only focuses on scientific aspects of synthesizing NEs with desired properties but also emphasizes engineering and economic consideration that is important in the oil industry.


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