45 research outputs found
Рациональный способ формирования стерневых кулис в Северном Казахстане
The main limiting factor for increasing yields in the arid steppe conditions of Northern Kazakhstan is moisture. Shoots are usually uneven due to the lack of moisture at the initial stage of their growing. The main source of moisture in this period is winter precipitation. Currently, the following methods of winter precipitation moisture accumulation are used in North Kazakhstan: leaving high standing stubble, seeding coulisses on pure fallow fields, herbicide (chemical) fallow field, snow ridging, harvesting of crops with continuous combining; and forming stubble coulisses. The most preferable way of increasing snow moisture accumulation is the formation of stubble coulisses that can be done in two ways.Research purpose Efficiency evaluation of the ways of forming stubble coulisses.Materials and methods Agroengineering and technological evaluation is used as a main research method of different ways of forming stubble coulisses, which is followed by the selection of a more preferable way.Results and discussion It has been found that in snowy winter both ways of forming stubble coulisses – with alternative passes of a direct combining reaper and a stripping reaper and using a direct combining reaper with a stripper adapter – have shown the same results. However, when there is a little snow in winter, the second way provides more intensive snow accumulation.Conclusions It has been experimentally found that using the direct combining reaper with the stripper adapter decreases labour inputs by 17.8% and total costs by 23.8% as compared to the formation of coulisses by using sequential passes of the direct combining and the stripping reapers. It has been found that the formation of stubble coulisses every 5-9 meters along with in-line para-plowing at a depth of up to 35 cm provides the highest yield increase of in snowy winter as compared to the conventional ways of moisture accumulation.Повышению урожайности в условиях засушливой степи Северного Казахстана препятствует отсутствие влаги. Из-за ее недостатка в почве в начальный период вегетации зачастую получают недружные и изреженные всходы. Основной источник влаги в почве в этот период – зимние осадки. Для их накопления хозяйства Северного Казахстана применяют различные способы: оставление высокой стерни; посев кулис на чистых парах; гербицидный пар; механическое снегозадержание; очес сельскохозяйственных культур в уборочный период, формирование стерневых кулис. Предпочтение отдают формированию стерневых кулис двумя способами.Цель исследования Оценить эффективность способов формирования стерневых кулис.Материалы и методы Применяли агротехническую и эксплуатационнотехнологическую оценку разных способов формирования стерневых кулис с последующим выбором наиболее предпочтительного варианта.Результаты и обсуждение Установили, что в снежные зимы способы формирования стерневых кулис чередующими проходами хедера и очесывающей жатки, и применением хедера с очесывающим адаптером показали равнозначные результаты. В малоснежные зимы второй вариант обеспечил наибольшее накопление снега.Выводы Подтвердили экспериментально, что применение хедера с очесывающим адаптером снижает затраты труда на 17,8 процента, а совокупные затраты – на 23,8 процента по сравнению со способом формирования стерневых кулис сочетанием проходов хедера и очесывающей жатки. Установили, что формирование стерневых кулис с межкулисным расстоянием 59 метров в сочетании со щелеванием на глубину до 35 сантиметров обеспечивает наибольшую прибавку урожая в снежные зимы по сравнению с известными способами накопления влаги
Structure of diffusion layers formed at liquid aluminum alloy-steel contact boundary
The microstructure and composition of diffusion layers that arise upon the spread of the liquid aluminum alloys AL5, AL9, AL852, and A7075 over the St3 steel has been investigated using optical and electron microscopy. The thermophysical conditions of the interaction of the melt with the substrate under which at the boundary of the substrate the plastic transition layer of iron-based solid solution improving quality of the coating is formed have been determined. © 2013 Pleiades Publishing, Ltd
Внебольничные пневмонии у взрослых больных ВИЧ-инфекцией: особенности течения и лечения, профилактика
This is a review of published data on community-acquired pneumonia (CAP) in adult HIV-infected patients. Morbidity of bacterial pneumonia in HIV-infected patients is 5- to 10-fold higher than that in general population. Wide use of antiretroviral therapy (ARVT) is associated with a reduction in morbidity of CAP in HIV-infected patients, but this reduction is not as significant as for other opportunistic infections. The most important risk factors for CAP are drug abuse, tobacco smoking, HIV-associated immunosuppression, hepatic cirrhosis, not to be treated with ARVT or ARVT withdrawal. Severe, complicated and invasive course of CAP and poor outcomes are seen more often in HIV-infected patients compared to general population. Bacterial pneumonia should be differed from pneumonia caused by Pneumocystis and from tuberculosis, especially in endemic countries and in patients with insidious onset of the disease. The standard therapy of CAP is applied in all patients independently of HIV status. However, administration of fluoroquinolones is restricted in regions with high prevalence of multi-drug resistant tuberculosis in HIV-infected patients before tuberculosis is excluded. Several studies have demonstrated that, in case of false initial diagnosis, 10-day monotherapy with a fluoroquinolone could form the resistance of Mycobacteria tuberculosis against this drug; this significantly complicates further treatment of tuberculosis and increases the treatment cost. Beta-lactams are not effective against tuberculosis; in 2016, WHO excluded macrolides from the list of medications for therapy of tuberculosis due to their low activity against M. tuberculosis. Therefore, empirical therapy of CAP in HIV-infected patients should be started with combination of beta-lactam antibiotic and newer macrolide. A strong protective effect of PPV23 vaccine against CAP was confirmed in HIV-infected patients, but the highest protective efficacy was seen in patients with relatively preserved immunity compared to patients with CD4 < 200 cells × µL-1.По результатам анализа публикаций показано, что заболеваемость бактериальной пневмонией у инфицированных вирусом иммунодефицита человека (ВИЧ) в 5–10 раз превышает показатель в популяции. При широкомасштабном применении антиретровирусной терапии (АРВТ) заболеваемость внегоспитальной пневмонией (ВП) снижается, но не так значительно, как в случае других оппортунистических инфекций. Наиболее значимыми факторами риска развития ВП признаны потребление наркотиков, табакокурение, ВИЧ-ассоциированная иммуносупрессия, цирроз печени и отсутствие АРВТ или перерывы в лечении. Развитие тяжелых, осложненных и инвазивных форм ВП и, как следствие, риск неблагоприятного исхода у больных ВИЧ-инфекцией встречается значительно чаще, чем среди населения в целом. В эндемичных по туберкулезу странах у больных ВИЧ-инфекцией бактериальную пневмонию наиболее часто приходится дифференцировать с пневмоцистной пневмонией и туберкулезом, особенно у лиц с подострым началом заболевания. Базовые принципы лечения ВП одинаковы для всех пациентов вне зависимости от ВИЧ-статуса. Однако в регионах с высоким бременем туберкулеза с множественной лекарственной устойчивостью микобактерий туберкулеза (МБТ) назначение фторхинолона ВИЧ-инфицированному пациенту с неисключенным туберкулезом имеет серьезные ограничения. Показано, что в случае ошибочного первоначального диагноза за 10 дней монотерапии фторхинолоном МБТ формируют устойчивость к препарату, что значительно усложняет и значительно повышает стоимость лечения туберкулеза. β-Лактамные антибактериальные препараты (АБП) не обладают противотуберкулезной активностью, а макролиды по причине чрезвычайно слабой активности в отношении МБТ Всемирной организацией здравоохранения в 2016 г. исключены из списка препаратов для лечения туберкулеза. Поэтому у ВИЧ-инфицированных наиболее оправданным началом стартовой эмпирической терапии ВП является именно комбинация β-лактамного АБП и современного макролида. Доказано, что вакцинация 23-валентной полисахаридной пневмококковой вакциной имеет серьезное проективное действие в отношении развития ВП у пациентов с ВИЧ-инфекцией, однако наиболее высокий индекс профилактической эффективности отмечен у лиц с относительно сохранным иммунитетом, нежели у больных с количеством CD4 < 200 клеток / мкл
Обоснование параметров хедеров и жаток-хедеров к зерноуборочным комбайнам различных классов в режиме неполной загрузки молотилки
The authors showed that in Kazakhstan northern region grain harvesters of 4, 5 and 6 classes did not provide the required level of productivity due to low yields. Longer harvesting period increased product losses. It was found that the harvesting machines were working in the incomplete loading mode of the thresher. The authors revealed the discrepancy between the standard sizes of the used reaping machines and regional zonal features.(Research purpose) To substantiate the parameters of headers and reaper-headers for combine harvesters in the incomplete loading mode of the thresher.(Materials and methods) The authors performed technical and economic calculations according to the criterion of operating costs for direct combining with a yield of 0.5 to 2.5 tons per hectare. The calculation was carried out for combine harvesters Vector-410 (class 4), Acros-550 (class 5), Essil-760 (class 6), aggregated with headers of different working widths.(Results and discussion) The authors determined that for the combine Vector-410 the rational width of the header was 9 meters in the yield range of 0.5-1.5 tons per hectare, and with a yield of 2.0-2.5 tons per hectare – 7-9 meters. For the combine Acros-550 the rational width of the reaper-header was 16 meters with a yield of 0.5-1.0 tons per hectare, with 1.5 tons per hectare - 9-12 meters, and with 2.0-2.5 tons per hectare – 7-9 meters. For the combine Essil-760 these values were 16; 12 and 9 meters respectively.(Conclusions) It was found that when comparing grain harvesters of 4, 5 and 6 classes with a yield of 0.5-2.0 tons per hectare, the lowest operating costs were provided by Acros-550 and Essil-760; with a yield of 2.0 tons per hectare - Vector-410; with a yield of 2.5 tons per hectare the Acros-550 was more effective.Показали, что на севере Казахстана зерноуборочные комбайны 4, 5 и 6 классов не обеспечивают требуемого уровня производительности из-за низкой урожайности. Растягивание периода уборки повышает потери продукции. Установили, что уборочные машины работают в режиме неполной загрузки молотилки. Выявили несоответствие типоразмеров применяемых жатвенных машин зональным особенностям региона.(Цель исследования) Обосновать параметры хедеров и жаток-хедеров к зерноуборочным комбайнам в режиме неполной загрузки молотилки.(Материалы и методы) Выполнили технико-экономические расчеты по критерию эксплуатационных затрат на прямом комбайнировании при урожайности от 0,5 до 2,5 тонны на гектар. Расчет проводили по зерноуборочным комбайнам Vector-410 (4 класс), Acros-550 (5 класс), Essil-760 (6 класс), агрегатируемым с жатками различной ширины захвата.(Результаты и обсуждение) Определили, что для комбайна Vector-410 в диапазоне урожайности 0,5-1,5 тонны на гектар рациональная ширина захвата хедера составляет 9 метров, а при урожайности 2,0-2,5 тонны на гектар – 7-9 метров. Для комбайна Acros-550 при урожайности 0,5-1,0 тонны на гектар рациональная ширина захвата жатки-хедера равна 16 метров, при 1,5 тонны на гектар – 9-12 метров, а при 2,0-2,5 тонны на гектар – 7-9 метров. Для комбайна Essil-760 этот показатель составляет 16; 12 и 9 метров соответственно.(Выводы) Установили, что при урожайности 0,5-2,0 тонны на гектар из сравниваемых зерноуборочных комбайнов 4, 5 и 6 классов наиболее низкие эксплуатационные затраты обеспечивают Acros-550 и Essil-760; при урожайности 2,0 тонны на гектар – Vector-410; при урожайности 2,5 тонны на гектар эффективнее Acros-550
Geogenic and atmospheric sources for volatile organic compounds in fumarolic emissions from Mt. Etna and Vulcano Island (Sicily, Italy)
In this paper, fluid source(s) and processes controlling the chemical composition of volatile organic compounds (VOCs) in gas discharges from Mt. Etna and Vulcano Island(Sicily, Italy) were investigated. The main composition of the Etnean and Volcano gas emissions is produced by mixing, to various degrees, of magmatic and hydrothermal components. VOCs are dominated by alkanes, alkenes and aromatics, with minor, though significant, concentrations of O-, S- and Cl(F)-substituted compounds. The main mechanism for the production of alkanes is likely related to pyrolysis of organic-matterbearing sediments that interact with the ascending magmatic fluids. Alkanes are then converted to alkene and aromatic compounds via catalytic reactions (dehydrogenation and dehydroaromatization, respectively). Nevertheless, an abiogenic origin for the light hydrocarbons cannot be ruled out. Oxidative processes of hydrocarbons at relatively high temperatures and oxidizing conditions, typical of these volcanic-hydrothermal fluids, may explain the production of alcohols, esters, aldehydes, as well as O- and S-bearing heterocycles. By comparing the concentrations of hydrochlorofluorocarbons (HCFCs) in the fumarolic discharges with respect to those of background air, it is possible to highlight that they have a geogenic origin likely due to halogenation of both methane and alkenes. Finally, chlorofluorocarbon (CFC) abundances appear to be consistent with background air, although the strong air contamination that affects the Mt. Etna fumaroles may mask a possible geogenic contribution for these compounds. On the other hand, no CFCs were detected in the Vulcano gases, which are characterized by low air contribution. Nevertheless, a geogenic source for these compounds cannot be excluded on the basis of the present data
Rational Way of Forming Stubble Coulisses under North Kazakhstan Conditions
The main limiting factor for increasing yields in the arid steppe conditions of Northern Kazakhstan is moisture. Shoots are usually uneven due to the lack of moisture at the initial stage of their growing. The main source of moisture in this period is winter precipitation. Currently, the following methods of winter precipitation moisture accumulation are used in North Kazakhstan: leaving high standing stubble, seeding coulisses on pure fallow fields, herbicide (chemical) fallow field, snow ridging, harvesting of crops with continuous combining; and forming stubble coulisses. The most preferable way of increasing snow moisture accumulation is the formation of stubble coulisses that can be done in two ways.Research purpose Efficiency evaluation of the ways of forming stubble coulisses.Materials and methods Agroengineering and technological evaluation is used as a main research method of different ways of forming stubble coulisses, which is followed by the selection of a more preferable way.Results and discussion It has been found that in snowy winter both ways of forming stubble coulisses – with alternative passes of a direct combining reaper and a stripping reaper and using a direct combining reaper with a stripper adapter – have shown the same results. However, when there is a little snow in winter, the second way provides more intensive snow accumulation.Conclusions It has been experimentally found that using the direct combining reaper with the stripper adapter decreases labour inputs by 17.8% and total costs by 23.8% as compared to the formation of coulisses by using sequential passes of the direct combining and the stripping reapers. It has been found that the formation of stubble coulisses every 5-9 meters along with in-line para-plowing at a depth of up to 35 cm provides the highest yield increase of in snowy winter as compared to the conventional ways of moisture accumulation
FORMATION OF THE METHODOLOGICAL APPROACH TO DEVELOPMENT OF STRATEGY OF MANAGEMENT OF TOWN-PLANNING ACTIVITY FOR SMALL TOWNS OF TRANS-BAIKAL TERRITORY
Subject: mechanism for forming a strategy of management of the urban development of a small town. The problem of managing the urban development in the Russian Federation, taking into account ongoing social and economic reforms, is relevant and important. The main attention in solving the problem is given to the normative and legal regulation and maintenance of the state real estate cadastre. At present, there is a need to formulate a strategy for managing the town-planning activity of territorial entities, oriented on the rational use of the land resources. The small cities of Russia, in the majority of cases, are in a critical condition, but have a huge land potential, which is the economic basis for development of the small town and a source for financing the local budget. Research objectives: theoretical and methodological approaches to the formation of a strategy for urban planning in small towns. Materials and methods: method of aggregation of indicators, correlation analysis. Results: the article examines theoretical approaches to the concept and classification of the category “small town” and specifics of the formation of a strategy for development of territorial entities in Russia and abroad, identifies their advantages and disadvantages. An algorithm for the formation of a strategy for managing the urban development of a small town is proposed. The technique of determining the strategic type of a small town has been created and based on this technique the ranking of small towns by strategic types was carried out. On the example of one of the depressed cities of Trans-Baikal territory, recipes for getting it out of this state, for example, with the help of the regional construction complex, are suggested. Conclusions: the practical application of the new methodological approach to the formation of a strategy for managing town-planning activity will improve the efficiency of the use of land resources of a particular small town
Intensity and width of bragg reflections from imperfect icosahedral quasicrystals obtained by simulating atomic growth.
International audienceThe Bragg reflections from icosahedral quasicrystals obtained in the course of a computer experiment on the simulation of crystal growth have been studied. The computer experiments based on the theory developed earlier allow one to “grow” in a computer the imperfect quasicrystals of nanometer dimensions. It is shown that the absolute value of the structure factor can be close to the maximum possible one for crystals, i.e., to the structure factor in the case where all the atoms scatter in phase. The spectral width of Bragg reflections is studied, and it is shown that the reflection width depends not only on the quasicrystal dimensions in the physical space but, also, on the perpendicular component of the reciprocal-lattice vectors. The data obtained are compared with the known experimental data