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排序方式: 共有1488条查询结果,搜索用时 250 毫秒
1.
Fluorescence‐Activated Cell Sorters: Standing Surface Acoustic Wave (SSAW)‐Based Fluorescence‐Activated Cell Sorter (Small 40/2018)
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Journal of Mechanical Science and Technology - The idea of integral calculus is used in traditional milling force prediction methods. In the traditional method, the milling cutter is divided into... 相似文献
3.
Changwei Dun Guoxi Xi Ye Zhang Tingting Zhao Yumin Liu Xiaoying Heng Lu Yao 《Ceramics International》2018,44(17):20984-20991
In this study, we investigated the effects of substituting Li+ for Co2+ at the B sites of the spinel lattice on the structural, magnetic and magnetostrictive properties of cobalt ferrites. The Li+ substituted cobalt ferrites, Co1-xLixFe2O4, with x varying from 0 to 0.7 in 0.1 increments, were synthesized with a sol-gel auto-combustion method using the cathode materials of spent Li-ion batteries. X-ray diffraction analysis revealed that all the Co1-xLixFe2O4 nanopowders had a single-phase spinel structure and the lattice parameters decreased with increasing Li+ content, which can be proved by slight shifts towards higher diffraction angle values of the (311) peak. Field emission scanning electron microscopy was used to observe the fractured inner surface of the sintered cylindrical rods and the increased porosity resulted in a decreased magnetostriction. The oxidation states of Co and Fe in the cobalt ferrite samples were examined by X-ray photoelectron spectroscopy. High resolution transmission electron microscopy micrographs showed that most particles were roughly spherical and with sizes of 25–35?nm. Li+ substitution had a strong effect on the saturation magnetization and coercivity, which were characterized with a vibrating sample magnetometer. The Curie temperature was reduced due to the decrease in magnetic cations and the weakening of the exchange interactions. The magnetostrictive properties were influenced by the incorporation of Li+ at the B sites of the spinel structure and correlated with the changes in porosity, magnetocrystalline anisotropy and the cation distribution. 相似文献
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概括介绍了现代公共建筑中餐饮废水的水质特点及处理要求,并结合公共建筑餐饮废水处理工艺的特殊性,对混凝法、生物法、电化学法等一些处理工艺及工程应用实例进行了综述.认为具备一体化、体积小、占地少、噪音低、处理效果好、运行管理方便等特点的新型餐饮废水处理技术将得到广泛的应用. 相似文献
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制备环丙沙星的哌嗪化工艺 总被引:2,自引:1,他引:1
采用乙氧羰基哌嗪与环丙羧酸缩合的方法,制备了环丙沙星。同时应用正交设计实验,研究了原料配比、温度、时间及溶剂用量对反应收率的影响,在优化条件下收率可达88.0%。 相似文献
7.
Bacterial communities associated with roots influence the health and nutrition of the host plant. However, the microbiome discrepancy are not well understood under different healthy conditions. Here, we tested the hypothesis that rhizosphere soil microbial diversity and function varies along a degeneration gradient of poplar, with a focus on plant growth promoting bacteria (PGPB) and antibiotic resistance genes. Comprehensive metagenomic analysis including taxonomic investigation, functional detection, and ARG (antibiotics resistance genes) annotation revealed that available potassium (AK) was correlated with microbial diversity and function. We proposed several microbes, Bradyrhizobium, Sphingomonas, Mesorhizobium, Nocardioides, Variovorax, Gemmatimonadetes, Rhizobacter, Pedosphaera, Candidatus Solibacter, Acidobacterium, and Phenylobacterium, as candidates to reflect the soil fertility and the plant health. The highest abundance of multidrug resistance genes and the four mainly microbial resistance mechanisms (antibiotic efflux, antibiotic target protection, antibiotic target alteration, and antibiotic target replacement) in healthy poplar rhizosphere, corroborated the relationship between soil fertility and microbial activity. This result suggested that healthy rhizosphere soil harbored microbes with a higher capacity and had more complex microbial interaction network to promote plant growing and reduce intracellular levels of antibiotics. Our findings suggested a correlation between the plant degeneration gradient and bacterial communities, and provided insight into the role of high-turnover microbial communities as well as potential PGPB as real-time indicators of forestry soil quality, and demonstrated the inner interaction contributed by the bacterial communities. 相似文献
8.
The influences of the growing process of sulfate-reducing bacteria (SRB) in seawater system on the medium state and corrosion behavior of carbon steel were studied by detecting solution state parameters and using corrosion electrochemical methods. The growing process of SRB in the seawater shows the three stages of growing, death and residual phases. The solution state parameters of the concentration of sulfide, the pH value and the redox potential changed during the three stages of the SRB growing process. And the corrosion rate of D36 carbon steel was accelerated during the growing phase and stable during the death and residual phases. The results indicate that the medium state and the corrosion rate of the steel do not depend on the number of active SRB, but depend on the accumulation of the metabolism products of SRB. 相似文献
9.
研制了一种微型橡胶同步带。强力层材料选用进口玻璃纤维线绳;包布层材料选用无锡产尼龙变形纱织物。带背和带齿胶料配合为:CR100;氧化锌4;硬脂酸1;软化剂5;氧化镁5;防老剂3.5;炭黑50;促进剂NA-22,TT,DM适量。经检测和实际应用证明,成品带各项性能指标均超过本所企业标准和日本JISK6379—89标准,并达到国内同类产品的先进水平. 相似文献
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