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1.
Yanlong Shi Xiaojuan Feng Haiyu Guan Jiahua Zhang Zhongai Hu 《International Journal of Hydrogen Energy》2021,46(12):8557-8566
Constructing high-efficient and nonprecious electrocatalysts is of primary importance for improving the efficiency of water splitting. Herein, a novel sunflower plate-like NiFe2O4/CoNi–S nanosheet heterostructure was fabricated via facile hydrothermal and electrodeposition methods. The as-fabricated NiFe2O4/CoNi–S heterostructure array exhibits remarkable bifunctional catalytic activity and stability toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline media. It presents a small overpotential of 219 mV and 149 mV for OER and HER, respectively, to produce a current density of 10 mA cm?2. More significantly, when the obtained electrodes are used as both the cathode and anode in an electrolyzer, a voltage of 1.57 V is gained at 10 mA cm?2, with superior stability for 72 h. Such outstanding properties are ascribed to: the 3D porous network structure, which exposes more active sites and accelerates mass transfer and gas bubble emission; the high conductivity of CoNi–S, which provides faster charge transport and thus promotes the electrocatalytic reaction of the composites; and the effective interface engineering between NiFe2O4 (excellent performance for OER) and CoNi–S (high activity for HER), which leads to a shorter transport pathway and thus expedites electron transfer. This work provides a new strategy for designing efficient and inexpensive electrocatalysts for water splitting. 相似文献
2.
生态林业建设是通过融入现代科技大大提升林业科技贡献率的新兴产业。文章针对生态林业建设技术推广工作存在的问题进行了分析,研究提出林业技术推广工作的作用和重要性,特别是通过提高我国林业产品质量、增强国际竞争力等,从而进一步提升林业技术推广水平的对策。 相似文献
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通过单因素实验和响应面法对啤酒酵母和乳酸菌发酵棕榈粕渣饲料制备工艺进行研究。结果表明:基料制备最佳发酵条件为发酵时间5 d、棕榈仁渣目数70目、菌料比1∶103、发酵温度30℃、含水量36%,该条件下基料中总菌落数为7.20×10~(10)个/g;发酵产物最佳发酵条件为发酵温度30℃、棕榈果渣与空果串配比1∶2、棕榈果渣及空果粉碎长度4 cm、配料比1∶10(基料与棕榈果渣和空果串质量比)、含水量35%、发酵时间36 d,该条件下发酵产物营养成分OD值为0.966。对发酵饲料主要成分进行分析,其粗蛋白、粗脂肪、粗纤维、粗灰分、钙、磷、含水量分别为7.20%、7.61%、26.20%、5.20%、0.38%、0.26%、16.20%,总菌落数为9.0×10~7个/g。该发酵方法工艺简单,具有良好的工业化生产前景。 相似文献
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Shou-Yi Li Zhen-Lai Liu Gen-Xiang Xiang Bao-Hong Ma Xiao-Ding Meng Yong-Lin He 《Ceramics International》2019,45(1):767-776
Herein, a novel hierarchical TiO2 pinecone-like structure (TPS) has been successfully fabricated for the first time by self-assembling anodic oxidation methods on the Ti plate. Then it was constructed that a series of CdS-TPS nanocomposites with different cycles CdS modifying by a successive ionic layer adsorption and reaction (SILAR) after different temperature annealing in air. The structures and properties of the CdS-TPS were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Current-voltage (I-V), ultraviolet-visible (UV–vis/DRS). The results shown that the optical properties of the CdS-TPS could be rationally tailored by adjusting the CdS-modified cycles and annealing temperature, which significantly enhanced photocatalytic activity. To be used in photocatalytic organic pollutant removal after optimizing both the CdS modification cycles and annealing temperature. The 15-CdS-TPS-500?°C exhibited significantly improved photocatalytic activities of methyl orange (MO) degradation under simulated sunlight irradiation. With 180?min, 85% of the MO (0.05?mM/L, 5?mL) was photodegraded and its kinetic constant reached to 0.0104?min?1, which is the 3.0 times and 3.6 times quicker than that of 5-CdS-TPS-500?°C and 15-CdS-TPS-0?°C, respectively. This could be ascribed to the result of the synergy effects of the suitable quantity of CdS nanoparticles modifier, the special surface structure, excellent crystallinity, higher electrical conductivity, and band structure matching. The possible photocatalytic mechanism of the CdS-TPS sample is investigated as well. 相似文献
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李海军 《数字社区&智能家居》2013,(22):5018-5020
文章叙述了服务器集群技术的概念,集群技术在电子商务、网络信息系统应用领域中的重要地位,集群技术的分类,几种不同集群技术的优缺点。 相似文献
9.
伴随着我国社会经济的稳固发展,人们的生活质量逐渐有了明显改善,而在生态问题趋于严重使人们的环境保护意识显著提高的过程中,森林抚育对于森林生态系统的作用和价值愈发凸显。对此,文章针对森林抚育,从提高森林利用率、维持森林动植物生态平衡、增加可利用水资源等多个方面就其对森林生态系统的影响进行了分析,旨在给予相关森林保护工作者可行的帮助,并以此促进我国森林开发工作的可持续发展。 相似文献
10.
曾贤兆 《兰州工业高等专科学校学报》2012,(1):68-71
黄仲则一生困顿,英才早逝,他的《竹眠词》创作成就虽不及诗歌,但依然具有绮丽缠绵、气象阔大、蕴藉深沉、流畅自然的美学风格。 相似文献