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861.
张登坪 《锻压装备与制造技术》2014,49(4):52-53
介绍一种数控分度冲槽卷绕机的钢带送进及控速装置,该装置可主动送进钢带,实时控制钢带的送进速度。解决了现有钢带送进速度无法精确控制而造成冲制槽型不齐的缺陷。 相似文献
862.
Cardoon (Cynara cardunculus L.) is an important perennial energy plant, which may produce sufficient biomass under reduced inputs. A 4-years field study was conducted in northern Greece and was repeated for three years in central Greece to determine the productivity of two cardoon varieties (‘Bianco Avorio’ and ‘C12’) under different water (irrigated or non-irrigated) and weed control (weedy or weed-free) conditions. In northern Greece, the density of weeds grown with cardoon increased as years went by, but in central Greece decreased. The absence of irrigation and the presence of weeds significantly reduced cardoon dry biomass, seed and oil yields, especially in the first two years of cultivation. In both environments, irrigated with 90 mm cardoon achieved 22–42% and 35–42% greater dry biomass and seed yield, respectively, than achieved the non-irrigated crop. In weedy cardoon, the dry biomass or seed yields reductions were 33–66% or 41–64%, respectively, in central Greece and 21–95% or 8–99%, respectively, in northern Greece. In central Greece cardoon productivity increased as years went by, but in northern Greece decreased. Generally, the cv. C12 was more productive than the cv. Bianco Avorio. Conclusively, the cardoon cv. C12 could provide satisfactory dry biomass, seed and oil yields for energy use in semi-arid Mediterranean fields, without irrigation or weed control inputs, on condition that they have been successfully established the first year. However, cardoon should be irrigated and weeded in order to provide sufficient yields. 相似文献
863.
TIAN Ya- qiang LI Wang WANG An- dong WEI Ying- li DONG Fu- tao CHEN Lian- sheng 《钢铁研究学报》2018,30(6):469-475
The multiphase microstructure and properties of low carbon steel by IQ&PB process under different partitioning temperatures and time were studied by means of SEM, EPMA, XRD and tensile testing. Results show that the microstructures of experimental steel consist of ferrite, bainite and retained austenite. With the increase of the holding time in two- phase region, the C and Mn contents apparently increase in martensite which transformed from austenite, and C and Mn content are 1. 47 times and 1. 16 times than average value of the base. With the decrease of the quenching and partitioning temperature, the volume fraction of the bainite increases, the microstructure is refined, and the content of M/A islands increases. With the temperature and time increased, the volume fraction of retained austenite at room temperature increases, the tensile strength decreases, the total elongation increases, and work hardening behavior occurrs continuously. When the partitioning time is 30min and the partitioning temperature is 400??, the tensile strength of the steel is 1107MPa, the elongation is 24%, the product of strength and elongation reaches above 26568MPa??%. 相似文献
864.
Performance evaluation is an important issue for optimal robot positioning within workcells. Performance indexes can provide essential contributions to such an evaluation, in particular if they can account for the specific task with respect to which the optimization is carried out. 相似文献
865.
《Measurement》2016
Thermal comfort is an important factor in human body. It can seriously impact on the livelihood factors of human such as lifestyle, productivity, societal activity, and health of an individual. It holds tremendous adverse affect toward diminishing of tolerance to other environmental hazards too. In this paper, an Internet of Things based cloud enabled measurement of MISSENARD index is proposed. A prototype system is implemented based on the proposed novel architecture for measuring thermal comfort of the indoor occupants. The system is developed to apprehend the Internet of Things based multiple cloud services as an important enabler for conferring to MISSENARD index monitoring in real time. The developed system holds a novel way of smarter integration of sensor fueled data analytics with cloud supported visualization at the same time. It further validates the usability of several plug-ins, different Application Programming Interfaces (API), heterogeneous network communications, and low power, memory constrained yet cost effective processor altogether to testify the underlying theory of Internet of Things to become prevalent into a reality. 相似文献
866.
《分离科学与技术》2012,47(17):2697-2707
Based on our earlier diagnosis that hydrophobic and hydrophilic (HPO/HPI) acids are the primary cause of short-term fouling in the ultrafiltration of secondary effluent, the HPO/HPI acids were extracted and subsequently characterized in comparison with commercial organic materials. HPO/HPI acids isolated from secondary effluent contained significantly fewer complex mixtures than humic substances that have been implicated as the dominant foulants in the filtration of surface water using porous membranes. The physicochemical and spectroscopic characterization demonstrated that the aromaticity and apparent molecular weight of HPO/HPI acids were lower than that observed for other humic materials, while the oxygenated functional groups were relatively higher. 相似文献
867.
Resilience is the capacity of complex system to be recovered after a sudden change of the indicator. Energy resilience is the ability of energy system to provide and maintain an acceptable level of service in the face of various challenges to normal operation. Loss of resilience can cause loss of valuable energy system services, and may even lead to rapid transitions or shifts into qualitatively different situations and configurations, 相似文献
868.
Phosphorescent OLEDs: Sky‐Blue Phosphorescent OLEDs with 34.1% External Quantum Efficiency Using a Low Refractive Index Electron Transporting Layer (Adv. Mater. 24/2016)
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869.
Zuo‐Yu Sun 《国际能源研究杂志》2018,42(3):1225-1236
In the present article, series of experiments were conducted to investigate turbulent explosion characteristics of stoichiometric syngas (with different hydrogen concentrations, 10%‐90% in volume fraction) in a 28.73‐L spherical turbulent premixed explosion system. The evolution of explosion pressure was recorded in different turbulent environment (with different turbulent intensity, 0.100‐1.309 m/s in root mean square value of velocity fluctuation). From the explosion pressure historic curves, the maximum pressure, lag duration, and explosion duration were obtained; the pressure rise rate and fast burn duration were derived; and deflagration index could be further calculated. The interaction effects of turbulent intensity and hydrogen addition on those explosion parameters were systematically analysed and discussed. Based on the results, an empirical formula about deflagration index of stoichiometric syngas was established. 相似文献
870.
This paper presents a new method based on wide area voltage stability index for optimal load shedding to prevent voltage instability phenomena. Phasor Measurement Units (PMUs) have widely been used in recent years due to their great advantages in power systems wide area monitoring, protection and control. The purpose of this paper is to provide a new optimal load shedding method, which disconnects the least possible amount of load from optimum buses. Not only the system stability is considered as main goal in this research, but also minimum load shedding is taken into account. Moreover, the problem of optimal load shedding is applied using modified Discrete Imperialistic Competition Algorithm (DICA) in mid-term and long-term voltage instability scenarios. In all investigations, certain limitations are considered to obtain practical answers. In addition, some modifications are applied to the conventional ICA, which make it proper for solving the optimal load shedding problem. New modifications result in fast convergence characteristic and less run time, which are crucial in dealing with power system instability problems. 相似文献