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961.
A simple and accurate high-performance liquid chromatography (HPLC) coupled with diode array detector (DAD) and evaporative light scattering detector (ELSD) was established for the determination of six... 相似文献
962.
In this investigation, biogas (BG) was used as an alternative fuel in a single-cylinder, four-stroke, air-cooled, direct injection (DI) diesel engine that was operated on a dual fuel mode. Biogas was produced from a non-edible seed de-oiled cake-pongamia pinnata (Karanja), which was collected from the biodiesel industries. The BG was inducted along with the air in suction of the engine at four different flow rates varying from 0.3?kg/h to 1.2?kg/h in steps of 0.3?kg/h. The investigation results revealed that BG inducted at a flow rate of 0.9?kg/h gives better combustion characteristics of engine behaviour than those of other flows throughout the engine operation. The ignition delay (ID) and combustion duration of the engine run by dual fuel operation at a BG flow rate of 0.9?kg/h were found to be longer by about 2 °CA and 2.9 °CA, respectively, in comparison with diesel at full load. The cylinder peak pressure was found to be overall higher by about 11?bar than that of diesel at full load. 相似文献
963.
《Food Control》2014
The interaction between food and metal packaging can be a potential source of trace elements release, which if ingested by humans can cause harmful effects. The present study is undertaken to investigate the leaching of elements from packaging materials into canned foods under different conditions of temperature, pH and storage period. Elemental analysis was done using Energy Dispersive-X-Ray Fluorescence (ED-XRF) for packaging materials and Inductively Coupled Plasma-Atomic Emission Spectrophotometry (ICP-AES) for canned foods. The concentration of Aluminum, Iron, Manganese, Silicon and Tin in the canned food products selected for analysis were found to be in range of 4.40–21.59 mg/kg, 2.38–19.70 mg/kg, 0.19–5.97 mg/kg, 16.46–359.63 mg/kg and 1.99–138.48 mg/kg respectively, when stored at room temperature within their shelf life storage period. The data revealed that the concentrations of elements under study were above the recommended limits of FAO/WHO Codex Alimentarius Commission. 相似文献
964.
965.
《Measurement》2014
Display pixels of liquid-crystal-display televisions (LCD TVs) on thin-film-transistor (TFT) array are getting smaller. This paper introduced the method of voltage imaging technique, which developed and provides initial insight into the thin-film-transistor array flaw detection and measurement for ultra-high-definition (Ultra HD, UHD) LCD TV application. We proposed the measurement of flaw detection, based on TFT array testing and characterization with respect to opto-electric transformation measurement. 相似文献
966.
A new approach to obtain a volumetric discretization from a T-spline surface representation is presented. A T-spline boundary zone is created beneath the surface, while the core of the model is discretized with Lagrangian elements. T-spline enriched elements are used as an interface between isogeometric and Lagrangian finite elements. The thickness of the T-spline zone and thereby the isogeometric volume fraction can be chosen arbitrarily large such that pure Lagrangian and pure isogeometric discretizations are included. The presented approach combines the advantages of isogeometric elements (accuracy and smoothness) and classical finite elements (simplicity and efficiency).Different heat transfer problems are solved with the finite element method using the presented discretization approach with different isogeometric volume fractions. For suitable applications, the approach leads to a substantial accuracy gain. 相似文献
967.
Dual phosphorylation of proteins is a principal component of intracellular signalling. Bistability is considered an important property of such systems and its origin is not yet completely understood. Theoretical studies have established parameter values for multistationarity and bistability for many types of proteins. However, up to now no formal criterion linking multistationarity and bistability to the parameter values characterizing dual phosphorylation has been established. Deciding whether an unclassified protein has the capacity for bistability, therefore requires careful numerical studies. Here, we present two general algebraic conditions in the form of inequalities. The first employs the catalytic constants, and if satisfied guarantees multistationarity (and hence the potential for bistability). The second involves the catalytic and Michaelis constants, and if satisfied guarantees uniqueness of steady states (and hence absence of bistability). Our method also allows for the direct computation of the total concentration values such that multistationarity occurs. Applying our results yields insights into the emergence of bistability in the ERK–MEK–MKP system that previously required a delicate numerical effort. Our algebraic conditions present a practical way to determine the capacity for bistability and hence will be a useful tool for examining the origin of bistability in many models containing dual phosphorylation. 相似文献
968.
《Mauerwerk》2017,21(4):253-266
For the design of unreinforced masonry walls under lateral earth pressure according to DIN EN 1996‐3 [1], the active earth pressure is used, which is less than the earth pressure at rest. For the consideration of active earth pressure, a sufficient deflection of the wall is needed. It is unknown whether the deflections in reality are large enough to justify a reduction of the active earth pressure. Therefore a numerical model has been developed which considers the load‐bearing behaviour of masonry walls, with several boundary conditions being considered to estimate the effective earth pressure. 相似文献
969.
970.
改革开放后30年,我国经济逐渐由计划经济转变为市场经济模式,随之而来的是规划编制工作的变革。针对文化迷失的现象,本文基于供求关系模型,以本溪市青云山公园规划策划为研究对象,采用定性分析与量化规划分析相结合的研究方法,对市场需求背景下城市文化规划内容和框架进行初步探讨。对应市场—空间规划策划的四步骤:文化需求、文化供给、市场落实和空间落实。以市场供求模型为基础,总结出以品质要求为导向满足消费者预期、以可持续供给为导向整合提升地域文化资源、以统筹区域文化资源为导向差异化市场落实、以提升空间品质为导向布局功能结构的规划策划研究。 相似文献