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11.
分析了注射模生产的现状,针对其生产中智能化调控应用方面的不足,提出模内参数的自适应调节方案,还介绍了自适应工作的原理、可调参数种类、逻辑推理等,并实际验证了基于注塑设备联网集成工艺数据下注射模成型工艺自适应调节的可行性。  相似文献   
12.
The Markov model and the PEM electrolyzer system model for directly coupled photovoltaic are combined to construct an efficient and reliable working condition that fits the fluctuation characteristics of solar energy. The working condition is designed through genetic algorithm so that the average coupling efficiency of the system can reach 98.8%. Then, the durability and recovery test are conducted on the basis of the constructed conditions. It is found that the attenuation rate at the current density of 1A/cm2 under the photovoltaic fluctuating condition reached 7.8mV/h, which is twice that under the constant current condition. The charge transfer impedance (Rct) is the main factor leading to the degradation. It is proved by the recovery experiment that the increase of Rct is related to the pollution of metal ions. After pickling to remove some metal ions, Rct can be significantly reduced by 46.8% and 65.2%, respectively. After the durability test, the voltammetric charges under the photovoltaic fluctuating condition and the constant current condition are reduced by 48.3% and 19.1% It indicates that the photovoltaic fluctuation condition will accelerate the attenuation of the effective reaction area of MEA, which is irreversible even after pickling. It can be observed from the SEM images that the catalyst layer of MEA has more obvious peeling under the photovoltaic fluctuation condition, which is not conducive to material transmission and destroys the transmission channel of ions and electrons. This result can provide a reliable reference for the coupling design of PEM electrolyzer and renewable energy in the future.  相似文献   
13.
This paper presents a physics-based compact gate delay model that includes all short-channel phenomena prevalent at the ultra-deep submicron technology node of 32 nm. To simplify calculations, the proposed model is connected to a compact α-power law-based (Sakurai-Newton) model. The model has been tested on a wide range of supply voltages. The model accurately predicts nominal delays and the delays under process variations. It has been shown that at lower technology nodes, the delay is more sensitive to threshold voltage variations, specifically at the sub-threshold operating region as compared with effective channel length variations above the threshold region.  相似文献   
14.
Lake Peipsi, one of the world’s largest lakes, is shared between Estonia and Russia. The water quality in different parts of the lake has so far been assessed independently. Here we explore opportunities for combining data of Estonian and Russian monitoring. For that, we 1) analysed the compatibility of data for some water quality variables; 2) estimated the potential effects of the differences in sampling frequency; 3) provided a few regression models to calculate the missing data for months not sampled by the Russian side. Data of the concurrent Estonian and Russian sampling indicated a good compatibility. Estonian data analysis suggested that water quality assessment results are sensitive to sampling frequency. For example, total phosphorus (TP) in the largest basin showed a long-term decreasing trend in three month data that disappeared when data for other months were added. Disregarding some months may lead to under- or overestimation of certain factors with no consistency in the response of different basins. Hence, data of the whole ice-free period are recommended for an adequate water quality assessment. Furthermore, we demonstrated that monthly values of the water quality variables of the same year are autocorrelated. Based on this, we filled the gaps in the long-term data and compiled a dataset for the whole lake that enables its most comprehensive use in water quality assessment and management. Long-term data revealed no water quality improvement of Lake Peipsi. Further reduction of the external nutrient load is needed. Eutrophication is sustained by high internal phosphorus load.  相似文献   
15.
Dense (1-x)wt%CaSnSiO5-xwt%K2MoO4 (CSSO-KMO) composite ceramics were fabricated by the cold sintering process at 180 °C under 400 MPa for 60 min. X-ray diffraction, Energy dispersive X-ray and Raman spectroscopy confirmed that CSSO and KMO coexisted without intermediate phases. As KMO weight fraction increased, relative permittivity (εr) and temperature coefficient of resonant frequency (τf) decreased and the microwave quality factor (Q×f, where f is resonant frequency) increased. Near-zero τf (-0.5 ppm/°C) was obtained for 65 wt%CSSO-35 wt%KMO with εr ~ 9.2 and Q×f ~ 6240 GHz. No chemical reaction between ceramic composites and silver was observed, demonstrating potential for cofiring with Ag-paste. A prototype antenna was fabricated from 65 wt%CSSO-35 wt%KMO composite ceramic with a bandwidth of 144 MHz @ -10 dB, a gain of 5.7 dBi and a total efficiency of 88.4 % at 5.2 GHz, suitable for 5 G mobile communication systems.  相似文献   
16.
生物质基喷气燃料是指全部或大部分来源于生物资源的喷气燃料,符合清洁低碳、安全高效的现代能源体系的要求。以生物质基喷气燃料替代传统石油基喷气燃料有助于我国早日实现“碳达峰、碳中和”的远大目标。在阐述生物质基喷气燃料生产工艺的发展历程及生物质基喷气燃料应用现状的基础上,提出高密度的生物质基喷气燃料是未来喷气燃料的发展方向,具有多环结构的生物质是合成高密度生物质基喷气燃料组分的优质原料;同时,总结了高密度生物质基喷气燃料组分生产工艺的研究进展,展望了生物质基喷气燃料未来的发展及挑战。  相似文献   
17.
Understanding the spheroidization process of micron-scaled α-Al2O3 powder in hydrothermal method is of great importance but still not completely revealed. The results demonstrated that SO42? played a significant role in the formation of spherical powder, while the bubble generated from the reaction of urea didn't work in the spheroidization process. The spheroidization process was summed up as two steps. The first was that SO42? limited the hydrolysis of Al3+ and reacted with Al3+ and OH- to form Al4(OH)10SO4, which nucleated and agglomerated into granular precipitates. The second was Ostwald ripening, which gave the spherical precursors a double-layered structure. When the spherical precursors obtained 120 °C were sintered at 1200 °C, α-Al2O3 were got and the spherical morphology still maintained with a large number of nano-sized pores. We anticipate the spherical α-Al2O3 with nano-sized pores can be applied in adsorption and filtration industries.  相似文献   
18.
In this paper, Zn-doped VO2 nanoparticles have been successfully fabricated by a two-step hydrothermal-annealing process, and the thermally induced visible light transmittance enhancement of Zn-doped VO2 has been studied for the first time. It is found that Zn-doped VO2 not only exhibits excellent solar modulation ability (ΔTsol = 15.27%) but also can reduce the phase transition temperature and increase the visible light transmittance after the heat-induced phase transition (ΔTlum=+5.78%). Moreover, with the increase of Zn doping concentration, the phase transition temperature (Tc) and phase transition hysteresis (ΔT) both decrease. It is shown that the Zn-doped VO2-PU films not only have good solar light modulation ability and properties of improving visible light transmission after phase transition, but also have good durability. The research result is of great significance for improving the visible light transmittance after phase transition and realizing the practical application of VO2 in the field of smart windows.  相似文献   
19.
20.
以具有降解亚硝酸盐功能的植物乳杆菌(Lactobacillus plantarum)SD-7和具有优良抗氧化能力的植物乳杆菌(Lactobacillus plantarum)FM-LP-9为复合发酵剂(1∶1),采用浅渍法发酵豇豆。以硬度和感官评分为考察指标,通过单因素试验及响应面试验研究复合发酵剂接种量、发酵温度和发酵时间对浅渍法发酵豇豆品质的影响。结果表明,最佳发酵工艺条件为发酵温度25 ℃,接种量5%,发酵时间125 h,在此优化条件下,得到的浅渍法发酵豇豆硬度为47.31 N,感官评分为90.98分,香气浓郁、口感脆嫩。  相似文献   
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