sequential transformation
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2021 ◽  
Vol 111 ◽  
pp. 107692
Author(s):  
Qingxiang Lin ◽  
Canjie Luo ◽  
Lianwen Jin ◽  
Songxuan Lai

2021 ◽  
Vol 13 (3) ◽  
pp. 1101
Author(s):  
Aleksandr Rakhmangulov ◽  
Konstantin Burmistrov ◽  
Nikita Osintsev

Sustainability of the open pit mining and technical system (MTS) is one of its key goals in the changing conditions of the external and internal environment. All MTS’s subsystems must function in concert to achieve this goal. The structure of the MTS is formed by many subsystems and elements, which are evaluated by a significant number of indicators. A comprehensive assessment of the MTS for all possible indicators is a complex and time-consuming task. However, each subsystem and element of the MTS has a different effect on the sustainability of this system. The MTS’s parameters change significantly during transition periods, for example, at a new stage of open-pit mining or when switching to an open-underground method of developing mineral deposits. The MTS’s sustainability declines during the transition periods. Changes in the parameters of technological processes during these periods can have a negative impact on the state of the economic and social subsystems of mining enterprises, as well as on the environment. Ensuring the sustainability of an MTS during transition periods requires the development of new approaches and principles for managing the work of mining enterprises, based on the alignment of economic goals, with goals in the field of ecology and social development. The study substantiates the key role of one of the MTS subsystems—the opening-up of an opencast system (OOS). It is shown that this system has a decisive influence on sustainable functioning and development. The systematization of the principles of sustainable functioning and development of mining enterprises and its systems has been carried out. Four groups of principles are distinguished: system-wide principles of management, principles of development of mining enterprises, principles of MTS development, and principles of the MTS’s subsystem development. The proposed system of principles is based on the idea of a sequential transformation of the subsystems at all stages of design and operation. A feature of the proposal system of principles is the consideration of economic, social, and environmental aspects to ensure the specified parameters for the sustainable functioning and development of mining enterprises. The results of the analysis of the factors of the external and internal environment of the MTS are presented. The parameters and indicators for assessing the sustainability of OOS and MTSs were selected and substantiated. The justified parameters and indicators were ranked using the fuzzy Analytic Hierarchy Process (AHP). The results of the assessment showed a high convergence of expert opinions on a group of economic parameters, which were rather high in technical and technological parameters. However, there is a divergence of expert opinions on social and environmental parameters. As a result of the study, it was concluded that the current management decisions are aimed at ensuring the economic and technological sustainability of MTS functioning, while achieving the goals of sustainable development of this system is not ensured. The methodology developed and presented in the study can be used to assess the sustainability of the functioning and development of MTSs.


Nanoscale ◽  
2021 ◽  
Author(s):  
B. Cirera ◽  
J. M. Gallego ◽  
J. I. Martínez ◽  
R. Miranda ◽  
D. Écija

This work reports the in-situ design of premetallated dysprosium porphyrin complexes (Dy-2H-4FTPP) on Au(111), whose Kondo resonance can be switched off with atomic precision by sequential transformation into partially and fully metallated species.


Akustika ◽  
2021 ◽  
pp. 141
Author(s):  
Nickolay Ivanov ◽  
Gennady Kurtsev ◽  
Aleksandr Shashurin

A rule for describing the sequential transformation of the sound fields when properties of the surfaces or structural elements change due to such basic processes as sound absorption, reflection, diffraction, or sound divergence is proposed. The main assumption is that sound fields are non-coherent, i.e., resonant phenomena and sound interference are not considered. The examples show solutions to such problems: - sound propagation in space if there are artificial structures; - sound propagation in the rooms; - efficiency calculation of the noise protection structures; - calculation of the expected noise level of the machinery and separation of the contribution of noise and vibration sources to sound fields (for example, an external sound field, a sound field in the office, etc.)


2020 ◽  
Vol 21 (20) ◽  
pp. 7601
Author(s):  
Tobias Bruun Pedersen ◽  
Mikkel Rank Nielsen ◽  
Sebastian Birkedal Kristensen ◽  
Eva Mie Lang Spedtsberg ◽  
Wafaa Yasmine ◽  
...  

Through stepwise recreation of the biosynthetic gene cluster containing PKS3 from Fusarium solani, it was possible to produce the core scaffold compound of bostrycoidin, a red aza-anthraquinone pigment in Saccharomyces cerevisiae. This was achieved through sequential transformation associated recombination (TAR) cloning of FvPPT, fsr1, fsr2, and fsr3 into the pESC-vector system, utilizing the inducible bidirectional galactose promoter for heterologous expression in S. cerevisiae. The production of the core metabolite bostrycoidin was investigated through triplicate growth cultures for 1–4 days, where the maximum titer of bostrycoidin was achieved after 2 days of induction, yielding 2.2 mg/L.


2020 ◽  
Vol 53 (6) ◽  
pp. 1434-1443
Author(s):  
Thomas Connolley ◽  
Oxana V. Magdysyuk ◽  
Stefan Michalik ◽  
Phoebe K. Allan ◽  
Manuela Klaus ◽  
...  

An experimental technique is described for the collection of time-resolved X-ray diffraction information from a complete commercial battery cell during discharging or charging cycles. The technique uses an 80 × 80 pixel 2D energy-discriminating detector in a pinhole camera geometry which can be used with a polychromatic X-ray source. The concept was proved in a synchrotron X-ray study of commercial alkaline Zn–MnO2 AA size cells. Importantly, no modification of the cell was required. The technique enabled spatial and temporal changes to be observed with a time resolution of 20 min (5 min of data collection with a 15 min wait between scans). Chemical changes in the cell determined from diffraction information were correlated with complementary X-ray tomography scans performed on similar cells from the same batch. The clearest results were for the spatial and temporal changes in the Zn anode. Spatially, there was a sequential transformation of Zn to ZnO in the direction from the separator towards the current collector. Temporally, it was possible to track the transformation of Zn to ZnO during the discharge and follow the corresponding changes in the cathode.


Molecules ◽  
2020 ◽  
Vol 25 (1) ◽  
pp. 203 ◽  
Author(s):  
Ying Lin ◽  
Dong Xing ◽  
Wen-Biao Wu ◽  
Gao-Ya Xu ◽  
Li-Fang Yu ◽  
...  

Herein, we design and synthesize an array of benzofuro[3,2-c]quinolines starting from 3-(2-methoxyphenyl)quinolin-4(1H)ones via a sequential chlorination/demethylation, intramolecular cyclization pathway. This sequential transformation was efficient, conducted under metal-free and mild reaction conditions, and yielded corresponding benzofuro[3,2-c]quinolines in high yields. In vitro biological evaluation indicated that such type of compounds showed excellent antileukemia activity and selectivity, and therefore may offer a promising hit compound for developing antileukemia compounds.


2019 ◽  
Vol 38 (19) ◽  
pp. 3752-3759 ◽  
Author(s):  
Xuewen Zhuang ◽  
Jia-Yi Chen ◽  
Zhuoyi Yang ◽  
Mengjing Jia ◽  
Chengjuan Wu ◽  
...  

Minerals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 489 ◽  
Author(s):  
Tolstykh ◽  
Palyanova ◽  
Bobrova ◽  
Sidorov

The Gaching high-sulfidation (HS) epithermal Au–Ag deposits, part of the Maletoyvayam ore field, which is located in the volcanic belts of the Kamchatka Peninsula (Russia). The main ore components are native gold, tellurides, selenides, and sulphoselenotellurides of Au and oxidation products of Au-tellurides. This study examines the different types of native gold in this ore deposit and the mechanisms and sequential transformation of calaverite (AuTe2) into mustard gold. The primary high fineness gold (964‰–978‰) intergrown with maletoyvayamite Au3Te6Se4 and other unnamed phases (AuSe, Au(Te,Se)) differ from the secondary (mustard) gold in terms of fineness (1000‰) and texture. Primary gold is homogeneous, whereas mustard is spongy. Two types of mustard gold were identified: a) Mixtures of Fe-Sb(Te,Se,S) oxides and fine gold particles, which formed during the hypogenic transformation stage of calaverite due to the impact of hydrothermal fluids, and b) spotted and colloform gold consisting of aggregates of gold particles in a goethite/hydrogoethite matrix. This formed during the hypergenic transformation stage. Selenides and sulphoselenotellurides of gold did not undergo oxidation. Pseudomorphic replacement of calaverite by Au-Sb(Te,Se,S,As) oxides was also observed.


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