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621.
The corrosion resistances of widely used X33CrNiMnN23-8, X50CrMnNiNbN21-9, X53CrMnNiN20-8 and X55CrMnNiN20-8 high-alloyed austenite valves steels in combustion engines have been compared. The comparison was performed on the basis of results of kinetic corrosion of the test steels in combustion gases from gasoline with 5% ethanol additive (v/v) and the combustion gases from propane-butane. The corrosion test was performed gravimetrically under thermal shock conditions by heating samples of the test steels from room temperature up to 1,173 K in exhaust gases from a combustion engine, and holding them at this temperature for 2 h and then cooling at room temperature for about 25 min. Then the same thermal shock was repeated and after every 10 to 20 such cycles the mass of the specimens was measured. This experiment simulated the working conditions of a highly thermal loaded exhaust valve in a spark ignited engine. The analysis performed shows that the corrosion resistances of X33CrNiMnN23-8 and X50CrMnNiNbN21-9 valve steels in an environment of combustion gases from propane-butane and in gases from gasoline with 5% ethanol additive (v/v) are comparable, whereas the corrosion resistance of X53CrMnNiN20-8 and X55CrMnNiN20-8 valve steels in an environment of combustion gases from propane-butane is slightly worse than in gases from gasoline with 5% ethanol additive (v/v).  相似文献   
622.
In profile monitoring, a relationship between a response variable and one or more explanatory variables is monitored. Different methods were developed for phase II monitoring of simple linear profiles. While some of the methods can be used to detect both increasing and decreasing shifts in the regression parameters, others need to be modified to enable detection of decreasing shifts in a process. In this paper, necessary modifications of the phase II methods for simple linear profile monitoring are proposed to improve their performance in detecting decreasing shifts. The paper also presents a performance comparison of several phase II methods.  相似文献   
623.
Streaming applications are built of data-driven, computational components, consuming and producing unbounded data streams. Streaming oriented systems have become dominant in a wide range of domains, including embedded applications and DSPs. However, programming efficiently for streaming architectures is a challenging task, having to carefully partition the computation and map it to processes in a way that best matches the underlying streaming architecture, taking into account the distributed resources (memory, processing, real-time requirements) and communication overheads (processing and delay). These challenges have led to a number of suggested solutions, whose goal is to improve the programmer??s productivity in developing applications that process massive streams of data on programmable, parallel embedded architectures. StreamIt is one such example. Another more recent approach is that developed by the ACOTES project (Advanced Compiler Technologies for Embedded Streaming). The ACOTES approach for streaming applications consists of compiler-assisted mapping of streaming tasks to highly parallel systems in order to maximize cost-effectiveness, both in terms of energy and in terms of design effort. The analysis and transformation techniques automate large parts of the partitioning and mapping process, based on the properties of the application domain, on the quantitative information about the target systems, and on programmer directives. This paper presents the outcomes of the ACOTES project, a 3-year collaborative work of industrial (NXP, ST, IBM, Silicon Hive, NOKIA) and academic (UPC, INRIA, MINES ParisTech) partners, and advocates the use of Advanced Compiler Technologies that we developed to support Embedded Streaming.  相似文献   
624.
The effect of dietary mixture of gallic acid and linoleic acid (MGL) on the antioxidative potential and quality of breast meat from broilers was investigated. Broilers during the 22–36 days on trial received 3 dietary treatments: 1) control (commercial finisher diet), 2) 0.5% MGL (gallic acid:linoleic acid = 1 M:1 M), and 3) 1.0% MGL. The feed efficiency, DPPH radical scavenging activity, ABTS+ reducing activity, reducing power, TBARS, and total phenolic content in the breast from the broilers improved significantly by 1.0% MGL dietary treatment. Arachidonic and docosahexaenoic acids were higher in the broilers fed both levels of MGL diets. In addition, water holding capacity of the breast was enhanced by the 1.0% dietary MGL treatment and was accompanied by a slight antimicrobial activity (1 decimal reduction) during storage. In conclusion, 1.0% dietary supplementation with MGL can improve the antioxidative potential, and nutritional and functional qualities of broiler breast meat.  相似文献   
625.
626.
The batch method was applied in order to determine the influence of phase contact time, solution pH and temperature as well as HCl concentration on nitroso-R-salt (NRS) deposition on the strongly basic anion-exchangers Amberlite IRA-402 and Amberlite IRA-958. The equilibrium sorption of NRS from 1 × 10− 4 mol/dm3 solution was achieved after 60 min. The amount of NRS adsorbed decreased with increasing hydrochloric acid concentration. A significant increase of NRS uptake is observed with the increase of initial solution pH up to 3 for Amberlite IRA-402. Amberlite IRA-402 and Amberlite IRA-958 in chloride form as well as modified by means of NRS were used for recovery of Pd(II) ions from 0.1, 0.5 and 1.0 mol/dm3 HCl solutions.The studied anion-exchangers in NRS form as far as their application in removal of Pd(II) chlorocomplexes is concerned can be presented in the order: Amberlite IRA-402 > Amberlite IRA-958.  相似文献   
627.
Precipitation of calcium carbonate was carried out in a draft-tube reactor by mechanical agitation of calcium hydroxide solution with carbon dioxide. The circulation of a reactive mixture was created by gas flow and a stirrer. It was observed that a higher circulation decreased the precipitation time and improved CO2 consumption. A higher circulation velocity of liquid contributed to smaller calcium carbonate particles at the end of precipitation.  相似文献   
628.
The multi-wedge cross rolling process of forming balls is described. The process tool for rolling 8 balls with a diameter of 35 mm is presented. The course of the rolling process, distributions of forming forces as well as maps of effective strain and temperature in the obtained balls are presented by finite element modeling (FEM). Experimental tests of simultaneous forming of 4 balls with a diameter of 22 mm conducted in laboratory conditions at Lublin University of Technology have proved that the balls obtained in multi-wedge cross rolling are of good quality and can therefore be used in both ball mills and rolling bearings.  相似文献   
629.
River Floods in the Changing Climate—Observations and Projections   总被引:2,自引:2,他引:0  
River flood damages, worldwide, have increased dynamically in the last few decades, so that it is necessary to interpret this change. River flooding is a complex phenomenon which can be affected by changes coupled to terrestrial, socio-economic and climate systems. The climate track in the observed changes is likely, even if human encroaching into the harm’s way and increase in the damage potential in floodplains can be the dominating factors in many river basins. Increase in intense precipitation has already been observed, with consequences to increasing risk of rain-induced flooding. Projections for the future, based on climate model simulations, indicate increase of flood risks in many areas, globally. Over large areas, a 100-year flood in the control period is projected to become much more frequent in the future time horizon. Despite the fact that the degree of uncertainty in model-based projections is considerable and difficult to quantify, the change in design flood frequency has obvious relevance to flood risk management practice. The number of flood-affected people is projected to increase with the amount of warming. For a 4°C warming the number of flood-affected people is over 2.5 times higher than for a 2°C warming. The present contribution addresses the climate track in an integrated way, tackling issues related to multiple factors, change detection, projections, and adaptation to floods.  相似文献   
630.
The hydrodynamics studies of the pulsed fluid bed (PFB) with lengthwise pulsation are reported in the article. The pulsed fluid bed with lengthwise pulsation is a modification of the classical PFB. In the PFB dryer with lengthwise pulsation, the disk gas distributor cyclically relocates the gas stream to each pressure chamber situated under the grid, parallel to the lengthwise axis of the main chamber. Such structure of a dryer is more compact than the previous ones. The operation range, pressure drops, and bed structure of a new system with lengthwise pulsation have been shown.  相似文献   
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