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91.
对在不同浓度的盐胁迫条件下,叶面喷施液态腐植酸和土壤施用腐植酸类物质对小麦作物生长和矿物营养吸收的影响进行了研究。通过添加不同量的NaCl得到不同的盐浓度环境。腐植酸类物质在作物种植前一个月施用,液态腐植酸在种苗发芽后20d和35d喷施于小麦叶面。腐植酸类物质的施用量为0、1g/kg、2g/kg,液态腐植酸的浓度为0、0.1%、0.2%。盐度对小麦生长具有负面影响,它会降低小麦对除Na、Mn以外的矿物营养的吸收,影响小麦干重。通过在土壤施用腐植酸类物质可以增加小麦对N的吸收,叶面施用腐植酸可增加其对P、K、Mg、Na、Cu和Zn的吸收。研究结果显示:在土壤中施用腐植酸类物质,不同盐浓度与施用量之间存在较好的相关性,但叶面喷施时盐度和喷施量之间相关性并不明显。在盐胁迫环境的影响下,叶面喷施腐植酸的初始浓度和土壤中施用的腐植酸类物质的初施量都增加了作物对营养元素的吸收。 相似文献
92.
In Rhizopus oryzae cultivations, lactate production decreased and ethanol and biomass productions increased as inoculated spore concentration increased. Spore concentrations of 1 x 10(3) and 1 x 10(4) spores ml(-1) induced tightly packed clumps, whereas 1 x 10(5) and 1 x 10(6) spores ml(-1) induced filamentous growth. 相似文献
93.
In supply chain management process, the firm select best supplier takes the competitive advantage to other companies. Thus, supplier selection is an important issue and with the multiple criteria decision-making approach, the supplier selection problem includes both tangible and intangible factors. This paper is aimed to present an integrated fuzzy and linear programming approach to the problem. Firstly, linguistic values expressed in trapezoidal fuzzy numbers are applied to assess weights and ratings of supplier selection criteria. Then a hierarchy multiple model based on fuzzy set theory is expressed and fuzzy positive and negative ideal solutions are used to find each supplier’s closeness coefficient. Finally, a linear programming model based on the coefficients of suppliers, buyer’s budgeting, suppliers’ quality and capacity constraints is developed and order quantities assigned to each supplier according to the linear programming model. The integrated model is illustrated by an example in a textile firm. 相似文献
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Sumengen B Manjunath BS 《IEEE transactions on pattern analysis and machine intelligence》2006,28(4):509-521
In this paper, we introduce new types of variational segmentation cost functions and associated active contour methods that are based on pairwise similarities or dissimilarities of the pixels. As a solution to a minimization problem, we introduce a new curve evolution framework, the graph partitioning active contours (GPAC). Using global features, our curve evolution is able to produce results close to the ideal minimization of such cost functions. New and efficient implementation techniques are also introduced in this paper. Our experiments show that GPAC solution is effective on natural images and computationally efficient. Experiments on gray-scale, color, and texture images show promising segmentation results. 相似文献
97.
Baris Sergi Ipek Bulut Ying Xia Dr. Zoë A. E. Waller Yasemin Yildizhan Dr. Ceyda Acilan Dr. Rianne M. Lord 《ChemMedChem》2021,16(15):2402-2410
To understand the potential in vitro modes of action of bis(β-diketonato) oxovanadium(IV) complexes, nine compounds of varying functionality have been screened using a range of biological techniques. The antiproliferative activity against a range of cancerous and normal cell lines has been determined, and show these complexes are particularly sensitive against the lung carcinoma cell line, A549. Annexin V (apoptosis) and Caspase-3/7 assays were studied to confirm these complexes induce programmed cell death. While gel electrophoresis was used to determine DNA cleavage activity and production of reactive oxygen species (ROS), the Comet assay was used to determine induced genomic DNA damage. Additionally, Förster resonance energy transfer (FRET)-based DNA melting and fluorescent intercalation displacement assays have been used to determine the interaction of the complexes with double strand (DS) DNA and to establish preferential DNA base-pair binding (AT versus GC). 相似文献
98.
Muhammad Waseem Ahmad Monjur Mourshed Baris Yuce Yacine Rezgui 《Building Simulation》2016,9(4):359-398
Buildings are responsible for 40% of global energy use and contribute towards 30% of the total CO2 emissions. The drive to reduce energy use and associated greenhouse gas emissions from buildings has acted as a catalyst in the development of advanced computational methods for energy efficient design, management and control of buildings and systems. Heating, ventilation and air-conditioning (HVAC) systems are the major source of energy consumption in buildings and ideal candidates for substantial reductions in energy demand. Significant advances have been made in the past decades on the application of computational intelligence (CI) techniques for HVAC design, control, management, optimization, and fault detection and diagnosis. This article presents a comprehensive and critical review on the theory and applications of CI techniques for prediction, optimization, control and diagnosis of HVAC systems. The analysis of trends reveals that the minimisation of energy consumption was the key optimization objective in the reviewed research, closely followed by the optimization of thermal comfort, indoor air quality and occupant preferences. Hardcoded Matlab program was the most widely used simulation tool, followed by TRNSYS, EnergyPlus, DOE-2, HVACSim+ and ESP-r. Metaheuristic algorithms were the preferred CI method for solving HVAC related problems and in particular genetic algorithms were applied in most of the studies. Despite the low number of studies focussing on multi-agent systems (MAS), as compared to the other CI techniques, interest in the technique is increasing due to their ability of dividing and conquering an HVAC optimization problem with enhanced overall performance. The paper also identifies prospective future advancements and research directions. 相似文献
99.
In the present paper, the performance and emission characteristics of a conventional four cylinder spark ignition (SI) engine operated on hydrogen and gasoline are investigated experimentally. The compressed hydrogen at 20 MPa has been introduced to the engine adopted to operate on gaseous hydrogen by external mixing. Two regulators have been used to drop the pressure first to 300 kPa, then to atmospheric pressure. The variations of torque, power, brake thermal efficiency, brake mean effective pressure, exhaust gas temperature, and emissions of NOx, CO, CO2, HC, and O2 versus engine speed are compared for a carbureted SI engine operating on gasoline and hydrogen. Energy analysis also has studied for comparison purpose. The test results have been demonstrated that power loss occurs at low speed hydrogen operation whereas high speed characteristics compete well with gasoline operation. Fast burning characteristics of hydrogen have permitted high speed engine operation. Less heat loss has occurred for hydrogen than gasoline. NOx emission of hydrogen fuelled engine is about 10 times lower than gasoline fuelled engine. Finally, both first and second law efficiencies have improved with hydrogen fuelled engine compared to gasoline engine. It has been proved that hydrogen is a very good candidate as an engine fuel. The obtained data are also very useful for operational changes needed to optimize the hydrogen fueled SI engine design. 相似文献
100.