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排序方式: 共有10000条查询结果,搜索用时 242 毫秒
91.
许揭平 《皮革制作与环保科技》2021,(2):72-73
磷酸盐是造成水体水质富营养化的重要污染因素,水体中能被藻类、植物直接利用的磷元素不只是能溶于水的正磷酸盐,其它状态的磷在一定条件下也能以"有效磷"的状态被植物吸收。对于生产单位排放的废水,需要监管的污染因子应该是总磷而不单是磷酸盐。采用钼酸铵分光光度法的实际测定结果其实是总磷,《广东省水污染物排放限值》中对该分析方法的名称应该由"磷酸盐"更正为"总磷"。 相似文献
92.
Min Mao Jing Xu Lingjiao Li Sheng Zhao Xuanhao Li 《International Journal of Hydrogen Energy》2021,46(45):23190-23204
Using sunlight to catalyze water to produce H2 is a key technology to solve the problem of energy shortage. In this research, perovskite-type NiMnO3 and Ni3S4 was recombined through secondary hydrothermal treatment. The optimal hydrogen evolution for composite materials NiMnO3/Ni3S4is 3.76 μmol mg?1 h?1, that 3.7 and 4 times more than that of two monomer materials, respectively. After four cycles of catalytic experiments, proving the high efficiency and stability of the composite catalyst. The characteristics of fluorescence spectroscopy and electrochemistry have confirmed the existence of p-n heterostructures, the excellent catalytic performance is related to the built-in electric field (accelerating the separation and utilization of photocharges) generated by the combination of NiMnO3 and Ni3S4. Strengthening the performance of the catalyst by constructing a heterostructure is an effective modification strategy and has positive application value in the fields of sensors and optoelectronics. 相似文献
93.
Cui Yang Xu Jin Xu Yuhui Shui Hengqi 《Electrical Engineering (Archiv fur Elektrotechnik)》2019,101(3):911-919
Electrical Engineering - The issue of magnetic flux leakage has received considerable critical attention, which severely reduces the transmission efficiency and loses a lot of energy in wireless... 相似文献
94.
Jiming Xu Howard M. Heys 《International Journal of Circuit Theory and Applications》2019,47(6):971-990
Side-channel attacks have shown to be efficient tools in breaking cryptographic hardware. Many conventional algorithms have been proposed to perform side-channel attacks exploiting the dynamic power leakage. In recent years, with the development of processing technology, static power has emerged as a new potential source for side-channel leakage. Both types of power leakage have their advantages and disadvantages. In this work, we propose to use the deep neural network technique to combine the benefits of both static and dynamic power. This approach replaces the classifier in template attacks with our proposed long short-term memory network schemes. Hence, instead of deriving a specific probability density model for one particular type of power leakage, we gain the ability of combining different leakage sources using a structural algorithm. In this paper, we propose three schemes to combine the static and dynamic power leakage. The performance of these schemes is compared using simulated test circuits designed with a 45-nm library. 相似文献
95.
Jiang Peng Liu Xu Cao Lixuan Wang Qian He Zhixia 《Journal of Mechanical Science and Technology》2021,35(9):4247-4259
Journal of Mechanical Science and Technology - A numerical study was performed to investigate the combustion characteristics of hydrogenated catalytic biodiesel (HCB)/gasoline reactivity controlled... 相似文献
96.
Wenwen Zhao Kuibao Zhang Weiwei Li Baozhu Luo Haibin Zhang Kai Xu 《Ceramics International》2019,45(9):11717-11722
In this study, transparent LaErZr2O7 ceramic with high excess La and Er contents (nominally La1.28Er1.28Zr2O7.84) was successfully prepared by vacuum sintering at 1850?°C for 6?h using nanosized powder. The XRD, SEM, EDX and TEM results reveal that the single pyrochlore phase in the powder sample transforms to the coexistence of La-rich pyrochlore phase and Er-rich defect fluorite phase after high temperature sintering. The high excess amounts of La and Er favor the formation of pyrochlore structure. Despite the coexistence of two phases, the sample with 1?mm thickness shows excellent in-line transmittance in the visible to mid-infrared region (as high as 81% at 1100?nm). The upconversion and infrared emission under 980?nm exciting were measured and discussed as well. 相似文献
97.
Xiaohong Hao Hang Suo Hui Peng Peixing Xu Xin Gao Su Du 《International Journal of Hydrogen Energy》2021,46(3):2890-2898
Microalgae is promising to be used as feedstock resources for hydrogen production due to its high oil and grease contents. This promotes the development of extraction technology of microalgae oil. In this study, based on the Rayleigh-Plesset equation, the effects of temperature, pressure, ultrasonic power and frequency on the bubble motion of ethanol ultrasound cavitation are investigated. Subsequently, the effects of different process parameters on the extraction rate are studied using Schizochytrium sp. as raw material by stirring or ultrasonic-assisted extraction. And the composition of algae extraction oil is analyzed. The results show that the amplitude of cavitation bubbles increases with the increase of ultrasonic power and decrease of ultrasonic frequency. The extraction rate of algae oil reaches 93.76 ± 0.48% when the ultrasonic power is 150 W, the reaction time is 30 min, the temperature is 50 °C and the liquid-solid ratio is 10:1. 相似文献
98.
Catalysis Letters - It is crucial to explore a facile synthesis of rutile TiO2 nanorods anchored at carbon cloth at low temperature for applicable air purifier. Herein, antler-like TiO2 rectangular... 相似文献
100.
徐炯 《酒.饮料技术装备》2022,(1)
随着中国饮料市场的升温,南京轻工业机械厂于2004年设计开发了YXP双端式饮料洗瓶机,该设备最初是针对百事可乐玻璃瓶进行清洗,后来为了提高洗净率演变成为附加超声波装置的,并且还研发出酸梅汤玻璃瓶清洗,瓶盒间距有83、78、105 mm。由于饮料瓶大部分不带标纸,所以该设备不带除标,我厂也根据带标饮料瓶又推出过带除标机构的饮料洗瓶机。箱体多种组合方式,一般为两碱槽,三个圆弧头,根据用户浸泡时间需要,对箱体进行了多种组合方式。 相似文献