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Crystal Structure of Methanolsodium Dianemycin — Methanol (1:2), Na(C47H77O14)(CH4O) • 2CH4O
No full textMicroorganisms such as bacteria, fungi, and algae produce a plethora of polyketide natural products. Most of these secondary metabolites are biosynthesized in order to protect the producing organism from other species present in the environment. A strain of Streptomyces milbemycinius NRRL 5739 is known for production of several antibacterial and antiparasitic substances or their precursors. We have unexpectedly isolated and recharacterized a natural product Dianemycin. We succeeded to crystallize the aforementioned natural product in the form of its methanol solvate. Dianemycin belongs to the class of carboxyl ionophores that complex the first row metal cations. The peculiarity of the present X-ray structure is sevencoordinated sodium cation
The System Approach to Transformer Substations` Placement in the Territory of Small Cities
No full textIn work the system approach to formation of the power supply system of small cities on example of Jurmala city is given. The mathematical and geometrical modeling of service areas for transformer substations of different voltage is fulfilled. The method of graphic alternative placement of transformer substations in the small city territory for new substations at existing structure of networks is offered. The calculation program Microsoft EXCEL and the graphic program AutoCad are used for realization of method. The method allows finding a rational decision for the development of small city power supply system on the beginning design stages in conditions of the information uncertainty
Innovative Approach for Studying Sustainable Development and Environmental Economics
No full textArticle is devoted to the analysis of application of different methods suitable for teaching sustainable development and environmental economics. The authors discuss the necessity to broaden meaning of several terms often used in mainstream economics, to encourage students not only to study sustainable development, but also implement the main ideas in everyday life as well as apply new technologies in the study process
Research on Corrosion Resistance of Decorative and Protective Ion Plasma Coatings on Ti-Al-N Base
No full textIn the vacuum deposition technology of ion-plasma coatings in advance is difficult to predict the outcome: whether a result is coating with desired decorative properties, whether it has necessary structure, chemical composition, high adhesion etc.
For the complex development process sequence of technological operations and experimental experience choosing the correct mode of the equipment is required. In addition to the decorative properties of coatings, some protective mechanisms should be added, such as corrosion resistance to changes in temperature, corrosive environments etc. The main knowledge of these problems is based on the chemical and physical properties of the deposited materials
ZnO nanodaļiņu iegūšana, īpašības un izmantošana
No full textMūsdienās liela uzmanība tiek pievērsta nanodaļiņu sintēzes pētījumiem. Tas ir saistīts ar to, ka, pārejot uz nanometru izmēriem, daļiņām parādās unikālas īpašības, kuras izmanto jauno, neparasto materiālu ražošanai
Time Depending Service Load Influence on Steel Tower Vibrations
No full textThis paper analyses the response of the tower structure to excitation caused by a human movement to assure safe exploitation and acceptable human comfort levels during the exploitation. There are adopted different levels of the structure and human behavior synchronization and its effect on the structure. This phenomenon (synchronization) should be taken into account because people respond naturally to a structure oscillation when structure has a frequency close to people natural movement frequency
Daudzstāvu ēku karkasu projektēšanas pamatprincipi saskaņā ar EC3 1.daļa. Ievads
No full textBrošūrā doti tērauda daudzstāvu ēku karkasu projektēšanas pamatprincipi saskaņā ar Eirokodeku 3
Synthesis of Malonic Acid Monoanilides
No full textCleavage of Meldrum`s acid with anilides was studie
Modelling and Simulation of Cloud Computing Solutions
No full textNowadays, the designing of cloud computing systems is actual approach which is developing very quickly. The cloud computing platform can be useful in any economy domain. Using of cloud computing can increase effectiveness of rural sector through cost savings of monitoring, practically unlimited data capacity for calculating of statistic values and industry values used by domain managers and decision makers. Usually cloud computing requires reengineering of legacy software systems. It means reengineering of currently operated information systems and applications used by domain enterprises and adapting these systems for cloud platform. Solving this problem causes necessity for architecture and functionality modelling of current systems or modelling newly designed systems. Domain owners expect clearly defined vision of system deployment and operation in cloud. An architectural solution of Cloud Computing systems has its own technical peculiarities and it is necessary to precisely describe and gauge them. Behaviour of Cloud systems depends on large number of stochastic factors. For estimation of operational behaviour of such systems determined mathematical expressions usually are insufficient. This kind of systems research tasks could be effectively implemented by stochastic simulation. This paper focuses on design of UML based Domain specific language for modelling and simulation of Cloud Computing systems. Initial Design of Unified Modelling Language (UML) based Domain Specific language (DSL) described in this paper achieves synergy from in IT industry widely used UML modelling technique and the domain specific Cloud Computing extensions. As a novelty for UML modelling, especially for simulation purposes, the presented DSL is enriched by a set of stochastic attributes of modelled activities. Such stochastic attributes are usable for further implementation of discrete-event system simulators
Factors Affecting the Dwelling Space Market Prices in Latvia
No full textThis paper describes the factors that influence the length and deepness of real estate market cycles in the dwelling space market in Latvia. Real estate market cycle length and deepness is influenced by factors like crediting, income level, demographic situation in the region and other factors. Authors in this paper describe how these factors affect the dwelling space market in Latvia. Understanding the factors that influence the real estate market and knowing the interconnections between them give an opportunity to develop an economically sustainable real estate market from which all participants of the sector would benefit