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排序方式: 共有431条查询结果,搜索用时 437 毫秒
251.
枸杞木虱天敌的保护与利用 总被引:7,自引:1,他引:7
记录了12种枸杞木虱天敌,描述了3种主要天敌的生物学特性,提出了保护利用天敌的有效措施。 相似文献
252.
Baoping Xin Di Zhang Xian Zhang Yunting Xia Feng Wu Shi Chen Li Li 《Bioresource technology》2009,100(24):6163-6169
The bioleaching mechanism of Co and Li from spent lithium-ion batteries by mixed culture of sulfur-oxidizing and iron-oxidizing bacteria was investigated. It was found that the highest release of Li occurred at the lowest pH of 1.54 with elemental sulfur as an energy source, the lowest occurred at the highest pH of 1.69 with FeS2. In contrast, the highest release of Co occurred at higher pH and varied ORP with S + FeS2, the lowest occurred at almost unchanged ORP with S. It is suggested that acid dissolution is the main mechanism for Li bioleaching independent of energy matters types, however, apart from acid dissolution, Fe2+ catalyzed reduction takes part in the bioleaching process as well. Co2+ was released by acid dissolution after insoluble Co3+ was reduced into soluble Co2+ by Fe2+ in both FeS2 and FeS2 + S systems. The proposed bioleaching mechanism mentioned above was confirmed by the further results obtained from the experiments of bioprocess-stimulated chemical leaching and from the changes in structure and component of bioleaching residues characterized by XPS, SEM and EDX. 相似文献
253.
Qingxi Li 《Insect Science》1994,1(2):146-149
Abstract In this paper, a new genus, Pseudomeromacrus and new species, Pseudamermacrus seti fenitus Li, is described. All type specimens are deposited in South China Agricultural University. 相似文献
254.
255.
Electrodes: A Combination of X‐Ray Tomography and Carbon Binder Modeling: Reconstructing the Three Phases of LiCoO2 Li‐Ion Battery Cathodes (Adv. Energy Mater. 8/2014)
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256.
Yanchen Liu Jing Wang Junwei Wu Zhiyu Ding Penghui Yao Sanli Zhang Yanan Chen 《Liver Transplantation》2020,10(5)
Li‐rich oxide is a promising candidate for the cathodes of next‐generation lithium‐ion batteries. However, its utilization is restricted by cycling instability and inferior rate capability. To tackle these issues, three‐dimensional (3D), hierarchical, cube‐maze‐like Li‐rich cathodes assembled from two‐dimensional (2D), thin nanosheets with exposed {010} active planes, are developed by a facile hydrothermal approach. Benefiting from their unique architecture, 3D cube‐maze‐like cathodes demonstrate a superior reversible capacity (285.3 mAh g?1 at 0.1 C, 133.4 mAh g?1 at 20.0 C) and a great cycle stability (capacity retention of 87.4% after 400 cycles at 2.0 C, 85.2% after 600 cycles and 75.0% after 1200 cycles at 20.0 C). When this material is matched with a graphite anode, the full cell achieves a remarkable discharge capacity (275.2 mAh g?1 at 0.1 C) and stable cycling behavior (capacity retention of 88.7% after 100 cycles at 5.0 C, capacity retention of 84.8% after 100 cycles at 20.0 C). The present work proposes an accessible way to construct 3D hierarchical architecture assembled from 2D nanosheets with exposed high‐energy active {010} planes and verifies its validity for advanced Li‐rich cathodes. 相似文献
257.
Critical tissue concentrations of potentially toxic elements 总被引:9,自引:0,他引:9
Summary Tissue concentrations of young plants, or of young leaves, of crop plants or species used as test plants offer some promise as simple and approximate indicators of toxic levels of elemental pollution of the soil environment.Theupper critical level of an element is the lowest tissue concentration at which it has toxic effects. The results of an extensive survey to extract critical levels from published work are presented for 29 elements. 相似文献
258.
259.
Jang‐Soo Lee Sun Tai Kim Ruiguo Cao Nam‐Soon Choi Meilin Liu Kyu Tae Lee Jaephil Cho 《Liver Transplantation》2011,1(1):2-2
In the past decade, there have been exciting developments in the field of lithium ion batteries as energy storage devices, resulting in the application of lithium ion batteries in areas ranging from small portable electric devices to large power systems such as hybrid electric vehicles. However, the maximum energy density of current lithium ion batteries having topatactic chemistry is not sufficient to meet the demands of new markets in such areas as electric vehicles. Therefore, new electrochemical systems with higher energy densities are being sought, and metal‐air batteries with conversion chemistry are considered a promising candidate. More recently, promising electrochemical performance has driven much research interest in Li‐air and Zn‐air batteries. This review provides an overview of the fundamentals and recent progress in the area of Li‐air and Zn‐air batteries, with the aim of providing a better understanding of the new electrochemical systems. 相似文献
260.
Jang‐Soo Lee Sun Tai Kim Ruiguo Cao Nam‐Soon Choi Meilin Liu Kyu Tae Lee Jaephil Cho 《Liver Transplantation》2011,1(1):34-50
In the past decade, there have been exciting developments in the field of lithium ion batteries as energy storage devices, resulting in the application of lithium ion batteries in areas ranging from small portable electric devices to large power systems such as hybrid electric vehicles. However, the maximum energy density of current lithium ion batteries having topatactic chemistry is not sufficient to meet the demands of new markets in such areas as electric vehicles. Therefore, new electrochemical systems with higher energy densities are being sought, and metal‐air batteries with conversion chemistry are considered a promising candidate. More recently, promising electrochemical performance has driven much research interest in Li‐air and Zn‐air batteries. This review provides an overview of the fundamentals and recent progress in the area of Li‐air and Zn‐air batteries, with the aim of providing a better understanding of the new electrochemical systems. 相似文献