Microorganisms such as bacteria and fungi play essential roles in many application fields, like biotechnique, medical technique and industrial domain. Microorganism counting techniques are crucial in microorganism analysis, helping biologists and related researchers quantitatively analyze the microorganisms and calculate their characteristics, such as biomass concentration and biological activity. However, traditional microorganism manual counting methods, such as plate counting method, hemocytometry and turbidimetry, are time-consuming, subjective and need complex operations, which are difficult to be applied in large-scale applications. In order to improve this situation, image analysis is applied for microorganism counting since the 1980s, which consists of digital image processing, image segmentation, image classification and suchlike. Image analysis-based microorganism counting methods are efficient comparing with traditional plate counting methods. In this article, we have studied the development of microorganism counting methods using digital image analysis. Firstly, the microorganisms are grouped as bacteria and other microorganisms. Then, the related articles are summarized based on image segmentation methods. Each part of the article is reviewed by methodologies. Moreover, commonly used image processing methods for microorganism counting are summarized and analyzed to find common technological points. More than 144 papers are outlined in this article. In conclusion, this paper provides new ideas for the future development trend of microorganism counting, and provides systematic suggestions for implementing integrated microorganism counting systems in the future. Researchers in other fields can refer to the techniques analyzed in this paper.
MoSe2 ultrathin nanospheres with three-dimensional network structure (MSS) were prepared by improved solvothermal method. These MoSe2 nanospheres are only 10 nm in size and actually composed of ultra-thin MoSe2 nanosheets with a thickness of only 2–3 molecular layers. Compared with the MoSe2 nanosheets (6–8 molecular layer thicknesses) of the three-dimensional flower structure (MSF) prepared by ordinary hydrothermal method, the MSS are thinner resulting in higher specific surface area of 5 times than that of MSF, and the light absorption ability at all UV–vis spectrum is stronger. The photocatalytic and photoelectrochemistry results show that the photocatalytic activity of MSS is 17 times that of the MSF, and the photoelectrochemical performance is twice. The results of electrochemical impedance spectroscopy and fluorescence spectroscopy confirmed that the MoSe2 ultra-thin nanospheres with three-dimensional network structure have lower internal resistance and higher carrier transport and separation efficiency. In the most important three aspects that determine the photoelectrochemical performance of photocatalyst: specific surface area, light absorption capacity, carrier transport and separation efficiency, MSS exceed MSF. This three-dimensional network nanospheres structure can improve the performance of MoSe2. This research successfully demonstrates the enhancement of the properties of MoSe2 two-dimensional materials through structural regulation. 相似文献
The ceramic nanocomposites (CNCs) like zirconia toughened alumina (ZTA) ceramics are important futuristic materials for structural and functional applications in advanced strategic systems, structural components, biomedical prostheses and devices. In all structural materials including the ZTA CNCs, the very early stages of plastic deformation i.e., the incipient plasticity events (IPE) are most important to be understood so that the microstructure and mechanical properties can be tuned to suit a given end application. Here we report for the first time the mechanisms of IPE in the nanoindentation experiments conducted at 10–1000 mN loads in the 40 ZTA CNCs. Here 40 ZTA CNC stands for 40 vol% of 3 mol% Yttria partially stabilized zirconia toughened alumina (40ZTA) CNC. The role of load ranges in variations of the IPE related parameters in the 40 ZTA CNCs is also studied. Further, an attempt is made to assess how the amount of zirconia content in ZTA CNCs affects the variations of the IPE related parameters. Through the extensive usage of field emission scanning electron microscopy (FESEM) and theoretical estimations, efforts are also directed to check out the linkage, if any, between the localized shear deformation and/or microcracking with the IPE events that occur in the present CNCs. In addition, a new concept of damage resistance is introduced for the first time in the present work to explain the presence of a strong indentation size effect (ISE) in the 40 ZTA CNCs. Finally, an attempt is also directed to understand how the indentation load (P) controls the relative size of interaction zones of dislocation loops as well as the damage resistance and thereby, engineer the acuteness of the ISE in ZTA CNCs. The implication of these findings in futuristic design of especially the ZTA CNCs for various applications is also discussed. 相似文献
Spinel Mg ferrites Mg1-xCdxCo0.05Fe1.95O4 (x=0.0, 0.2, 0.3 and 0.4) as potential agents for the miniaturization of high frequency antennas are presented. All the synthesized compositions were experimentally revealed to possess pure spinel phase. Dual-equivalent permeability and permittivity (μ'≈26, ε'≈25, x=0.3 and μ'≈29, ε'≈28, x=0.4) from 5 to 100 MHz can be achieved by introducing Cd2+ ions, yielding large miniaturization factors of up to 25 and 28. To figure out the effects of Cd2+ ions substitution on magnetic and dielectric properties, the change in microstructure is mainly investigated. Meanwhile, enhanced magnetic properties including upward saturation magnetization (Ms) (approximately 47.60 emu/g) and reduced coercivity (approximately 54.22 Oe) are obtained due to increased grain size and denser microstructure arrangements reflected from scanning electron microscopy images. With low magnitude order of magnetic and dielectric losses factors (tanδε reaches 10-4, tanδμ reaches 10-2), the composites can potentially exhibit high operating efficiencies at high frequencies. 相似文献
In this article, a theoretical model for predicting the equilibrium morphology of gas–liquid Janus droplets was built. Based on this model, the effects of bubble radius and volume ratio on morphology change was systematically studied. The increase of bubble radius causes the two parts (bubble and oil drop) in Janus droplets tend to merge while the impact of volume ratio is complicated. When volume ratio increases, these two parts firstly tend to merge, then gradually separate. The accuracy of this model was verified by experimental results. 相似文献
In this work, a cascade structure among ZnSe, carbon membrane and TiO2 NTAs was constructed precisely. This carbon membrane bridged ZnSe and TiO2 composite exhibits excellent H2 evolution activity, the H2 evolution rate of ZnSe/C/TiO2 NTAs (866.76 μmol/cm2) is about 6.95 times higher than that of pure TiO2 NTAs (124.64 μmol/cm2) after 200 min irradiation. The introduction of carbon membrane can greatly facilitate the electron transfer from ZnSe to TiO2, ZnSe/C/TiO2 ternary composite exhibits the highest transient photocurrent density (1.05 mA/cm2) and the lowest impedance (677.6 Ω) among all the samples. Besides, the contact between TiO2 and electrolyte is improved after introducing carbon membrane, therefore C/TiO2 NTAs shows more positive flat band potential of (1.86 V) compared with TiO2 NTAs (0.50 V). It is also found that pure carbon powder can achieve H2 production under visible light irradiation, its sensitization effect can further improve photocurrent density of the composite under 500 nm light radiation, the electrons produced in carbon film can inject into TiO2, and holes from TiO2 can quickly transfer to carbon film, leading to excellent H2 evolution efficiency. 相似文献
The stake of distributed generation resources like fuel cell in daily market is proved to be a major uncertain problem. The volatile character of market price together with the unbalanced nature of power can take hold of economic advancement of distributed generation resources which in turn can culminate in diversion retribution while the market is being struck. This study introduces a market participation model in share conditions to improve the profit for Fuel Cell/wind turbine/storage/photovoltaic and demand response. To solve the mentioned problem, an accurate prediction model is presented in this paper. This model is based on complete ensemble empirical mode decomposition, and multiple artificial neural network which is coupled with Broyden water cycle algorithm. By this algorithm, the prediction accuracy of proposed forecast engine is enhanced and could get the better results. A sure-footed stochastic optimization approach was deployed in order to take prices of markets and distributed generation resources into account. In the generation of distributed generation resources, forecasting error database in everyday, modified, and depressed market was drawn on to induce probabilistic scenario. Improbable variables were discarded by a neuro-fuzzy model. Eventually, to illustrate the joint model strategy suggested in the study, a testing system contains fuel cell/wind turbine/storage unit/photovoltaic and demand response was utilized and the attained results were calculated in two different periods. 相似文献
The ceramic coatings on the surface of aluminum alloy substrates with micro-grooves have been successfully fabricated in the silicate solution via micro-arc oxidation (MAO) approach. Microstructure characterization showed that the larger main discharge channels were located in the center of micro-groove, the smaller secondary discharge channels were located on both sides of main discharge channel; and a few irregular micro-pores existed in the vicinity of all discharge channels, which were mainly cause by the rapid cooling and solidification of discharge channels hindering the removal of gases produced via reaction. Moreover, the growing direction of coating in the initial stage was mainly outward-growth and resulted in the formation of inverted triangle coating structure, which was due to the sharp-angled effect. But in the final growing stage, the inward-growth behavior played a key role owing to the spark transfer. According to above results and discussion, the formation of smooth, uniform and homogeneous ceramic coating on the surface of whole trapezoidal micro-groove substrate contained four stages: anodic oxidation growth, sharp corner rapid growth, coating homogenization and groove self-filling. 相似文献