439 research outputs found
Influence of Fires, Fungi and Mountain Pine Beetles on Development of a Lodgepole Pine Forest in South-Central Oregon
Virtually pure lodgepole pine stands form an edaphic climax community over large areas of the infertile pumice plateau of south-central Oregon. During our ongoing studies on the dynamics of these forest we developed the scenario that periodic fires create fungal infection courts in damaged roots; in time, advanced decay develops in the butts and stems of these trees. The mountain pine beetle preferentially selects and kills these trees during the flight season. As these outbreaks develop, additional uninfected trees are attacked. In time, the stage is set for subsequent fires as needles drop, snags fall, and logs decay
Регулируемый электропривод погружного насоса ЭЦВ 6-6,5-125
Исследование технологического процесса автоматического поддержания уровня воды в резервуаре. Выбор оборудования. Расчет параметров и характеристик АД. Система автоматического управления электроприводом. Разработка модели системы автоматического поддержания воды в резервуаре в MexBIOS Development StudioResearch of technological process of automatic maintenance of a water level in the tank. Choice of equipment. Calculation of parameters and characteristics of induction motor. The system of automatic control of the electric drive. Development of a model of automatic water storage system in a tank using MexBIOS Development Studi
Нефтегазоносные карбонатные породы палеозоя арктической части Западной Сибири (на примере Новопортовского и Бованенковского структурно-фациальных районов)
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Growing healthy seedlings : identification and management of pests in Northwest forest nurseries
This book provides an illustrated guide to the identification and management of fungi, insects, and abiotic conditions that cause problems in Northwest bareroot conifer nurseries. A key to nursery pests offers initial guidance in identification. Separate chapters address individual pests with details on recognition, damage cycle, and management practices to reduce losses. A final chapter discusses the integration of pest-management practices into the entire nursery operation. Tables of pesticides and pests controlled, a checklist of control activities keyed to the seedling growth cycle, and a glossary of terms conclude the book
Peroxyoxalate chemiluminescence detection for the highly sensitive determination of fluorescence-labeled chlorpheniramine with Suzuki coupling reaction.
A sensitive and selective high performance liquid chromatography-peroxyoxalate chemiluminescence (PO-CL) method has been developed for the simultaneous determination of chlorpheniramine (CPA) and monodesmethyl chlorpheniramine (MDCPA) in human serum. The method combines fluorescent labeling with 4-(4,5-diphenyl-1H-imidazole-2-yl)phenyl boronic acid using Suzuki coupling reaction with PO-CL detection. CPA and MDCPA were extracted from human serum by liquid-liquid extraction with n-hexane. Excess labeling reagent, which interfered with trace level determination of analytes, was removed by solid-phase extraction using a C18 cartridge. Separation of derivatives of both analytes was achieved isocratically on a silica column with a mixture of acetonitrile and 60 mM imidazole-HNO(3) buffer (pH 7.2; 85:15, v/v) containing 0.015% triethylamine. The proposed method exhibited a good linearity with a correlation coefficient of 0.999 for CPA and MDCPA within the concentration range of 0.5-100 ng/mL. The limits of detection (S/N = 3) were 0.14 and 0.16 ng/mL for CPA and MDCPA, respectively. Using the proposed method, CPA could be selectively determined in human serum after oral administration
High-Pressure Methane Adsorption and Characterization of Pores in Posidonia Shales and Isolated Kerogens
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