Disposal of animal carcasses by co-composting with animal waste usually selected conventional carbon to nitrogen (c/N) ratio around 25:1, in which the compost is widely used throughout the world. In this study, the pi...
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Disposal of animal carcasses by co-composting with animal waste usually selected conventional carbon to nitrogen (c/N) ratio around 25:1, in which the compost is widely used throughout the world. In this study, the pig carcass tissue blocks were sampled for composting at a laboratory scale to evaluate the effect of c/N ratio on the pig carcass compost. The time of thermophilic phase between 60 degrees c - 70 degrees c at a lower c/N ratio of 20:1 was significantly longer than that at the conventional c/N ratio, and it was the only one with the temperature beyond 70 degrees c that lasted for 2 days. Germination index and T value (the final c/N ratio / the initial c/N ratio) of the treatment with a c/N ratio of 20:1 were 94.67% and 0.69, respectively, meeting the standards of animal carcass compost. The degradation rate was 75.67%, and no significant difference was obtained as compared to the conventional c/N ratio groups. Organic fertilizer produced from the treatment with a c/N ratio of 20:1 was selected to evaluate the fertility by pot experiment of cayenne pepper compared with chemical fertilizer. The results showed that organic fertilizer from this treatment could significantly improve the growth of cayenne pepper. Overall, the use of the lower c/N ratio of 20:1 in the disposal of pig carcass by co-composting with swine manure could achieve the similar degradation rate as well as the maturity and stability of organic fertilizer as compared with the traditional c/N ratio at lab scale.
We report a novel fusion of microfluidics and light-field microscopy, to achieve high-speed 4D (space + time) imaging of moving c. elegans on a chip. Our approach combines automaticchip-based worm loading/ compartmen...
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We report a novel fusion of microfluidics and light-field microscopy, to achieve high-speed 4D (space + time) imaging of moving c. elegans on a chip. Our approach combines automaticchip-based worm loading/ compartmentalization/flushing/reloading with instantaneous deep-learning light-field imaging of behaving worm. Taken together, we realized intoto image-based screening of wild-type and uncoordinated-type worms at a volumetric imaging rate of 33 Hz, with sustained observation of 1 worm per minute and totally 42 worms per hour. Through four-dimensionally visualizing the dynamics of all the worms at an ultra-high throughput of 84000 image volumes in an hour, we can quantitatively analyze their behaviors as well as the neural activities, and correlate the phenotypes with the neuron functions. The different types of worms can be readily identified as a result of the high-throughput activity mapping. Our approach shows great potential for various lab-on-a-chip biological studies, such as high-throughput embryo sorting and cell growth assays.
A modification of the precursor infiltration pyrolysis (PIP) method was explored to prepare the integrated doped ceramic matrix and coating by the added Sic nanowires layer and shape-stabilization process. The epitaxi...
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A modification of the precursor infiltration pyrolysis (PIP) method was explored to prepare the integrated doped ceramic matrix and coating by the added Sic nanowires layer and shape-stabilization process. The epitaxial layer of Sic nanowires provided surficial attachments for the precursor. And the shape-stabilization process aggregated loose ceramic particles into a coating. Then the Sic nanowire-reinforced Zrc-Siccoating-matrix integrated c/c (S/SZ-cZ/c) composite was simply prepared by the modified PIP method. The bonding strength between the coating and matrix of the S/SZ-cZ/ccomposite was improved. Through the ablation test, the mass and linear ablation rate of the S/SZ-cZ/ccomposite were 0.46 mg/s and 0.67 mu m/s, which were 60.34 % and 74.91 % lower than those of the Sic nanowire-reinforced c/c-Zrc (S/cZ/c) composite, respectively. The integration of the coating and matrix enabled the formation of a continuous oxide layer of molten SiO2 and ZrO2 in the ablation process, which helped to block the oxygen and heat during the ablation test. Thus the ablation resistance of the materials was systematically and effectively improved.
Poor thermal conductivity, especially in thickness direction, is a major obstacle to extend the service lifetime of c/Siccomposite. However, there are few papers focusing on finely designing heat conductive channel b...
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Poor thermal conductivity, especially in thickness direction, is a major obstacle to extend the service lifetime of c/Siccomposite. However, there are few papers focusing on finely designing heat conductive channel but a simply introduction of various modifiers to improve c/Sic thermal conductivity, which leads to less success. Herein, multi-layer graphene sheets were utilized to improve the thermal conductivity of c/Siccomposites via an effective method to design graphene heat conductive channels. To determine the role of graphene sheets in improving thermal conductivity, the effect of the different loading fractions of graphene and microstructure of as-prepared composites were systemically investigated. Results revealed that the thermal conductivity of composites increased by 204% with well-designed graphene heat conductive channels. Besides, compared with the porosity, the orderly aligned heat conductive pathways played a more important role in thermal conductivity. This work provides a new and effective method for preparing well-designed heat conductive channels to enhance thermal conductivity of c/Sic.
The application of c/c-Siccomposites remains a challenge because of the poor mechanical properties induced by the liquid silicon infiltration method. In this study, a thick high textured pyrolyticcarbon (HT Pyc) int...
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The application of c/c-Siccomposites remains a challenge because of the poor mechanical properties induced by the liquid silicon infiltration method. In this study, a thick high textured pyrolyticcarbon (HT Pyc) interface manufactured by chemical vapor infiltration (cVI) was used to protect the carbon fibers and improve the flexural properties. The microstructure of HT Pyc, its flexural properties, and its associated strengthening and toughening mechanisms were analyzed on the c/c-Siccomposites. The results showed that the bending strength of the c/cSiccomposites was 344.74 MPa, which is nearly 31.82% higher than that of c/ccomposites. The fracture mode transformed from brittle fracture to pseudoplastic fracture owing to the addition of Sic, and the c/c-Siccomposites maintained a better toughness compared to c/ccomposites. Multiple mechanisms of strength and toughness improvement were found to be responsible for the excellent performance of the c/c-Siccomposites. The HT Pyc interface played a critical role in the excellent flexural properties. The strong bonding among the carbon layers and high interfacial strength between the fiber and HT Pyc led to the increase of strength. Besides, the improvement in toughness was attributed to the multiple effects of the carbon-layers deformation, cracks deflection and propagation caused by the bridging areas, sublayers, nano-and micro-scale cracks.
Dependence of the combustion of a Ti + c granular charge on a granule size is experimentally studied. It is revealed that the burning rate of a granular mixture of all fractions used in the work is higher than the bur...
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Dependence of the combustion of a Ti + c granular charge on a granule size is experimentally studied. It is revealed that the burning rate of a granular mixture of all fractions used in the work is higher than the burning rate of a bulk-density powder mixture. It is shown that, with a decrease in the granule size, the burning rate of the charge in the absence of gas decreases due to an increase in the number of boundaries between the granules per unit length of the sample. A strong influence of the nitrogen flow on the burning rate of both coarse and fine granules is established. It is shown that, in contrast to fine granules, an increase in the nitrogen flow rate of coarse granules up to 600 liters/h leads to a transition to convective combustion. The studies performed indicate that, despite the structural analogy between mechanically activated and granular mixtures, the relationship between the combustion time and the front transition time in granular mixtures is completely different. This means that the combustion of granular mixtures even in the absence of a gas flow cannot be explained within the framework of a microheterogeneous model.
c/MgO composite powders were prepared by combustion synthesis using magnesium oxalate and magnesium powders as raw materials. The phase composition and microstructure of the composite powders were investigated by X-ra...
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c/MgO composite powders were prepared by combustion synthesis using magnesium oxalate and magnesium powders as raw materials. The phase composition and microstructure of the composite powders were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy/energy dispersive spectroscopy (FESEM/EDS), high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy. The synthetic mechanism was explored through TG-FTIR and combustion front quenching techniques. It was found that the c/MgO composite powders contained a large quantity of MgO nanofibers. When the molar ratio of magnesium oxalate and magnesium was 1:4, the carbon content of the product reached a maximum of 9.45 wt %. In the composite powders, cubic MgO particles were encapsulated by a thin carbon layer, and there was a tiny gap between MgO and the carbon layer;a large number of MgO nanofibers with aspect ratios of 80?100 were found. The cubic MgO particles of the products are the direct decomposition of Mgc2O4, and the MgO nanofibers are the reaction product of gaseous Mg and cO2/cO at high temperature. Meanwhile, the carbon deposited on the MgO particles can inhibit the grain growth of MgO particles and result in the refinement of MgO particles. The uniform dispersion of carbon and the weak c/MgO interface combine, making the composite powders a potential additive for low-carbon MgO?c refractories with excellent thermal shock resistance.
In order to study the effects of temperature on the material behavior of Liquid Silicon Infiltration (LSI) based continuous carbon fiber reinforced silicon carbide (c/c-Sic), the mechanical properties at room temperat...
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In order to study the effects of temperature on the material behavior of Liquid Silicon Infiltration (LSI) based continuous carbon fiber reinforced silicon carbide (c/c-Sic), the mechanical properties at room temperature (RT) in in-plane and out-of-plane directions are summarized and the tensile properties of c/c-Sic were then determined at high temperature (HT) 1200 degrees c and 1400 degrees c under quasi static and compliance loading. The stressstrain response of both HT tests is similar and almost no permanent strain can be observed compared to the RT, which can be explained through the relaxation of residual thermal stresses and the crack distribution under various states. The different fracture mechanisms are confirmed by the analysis of fracture surface. Furthermore, based on the analysis of hysteresis measurements at RT, a modeling approach for the prediction of material behavior at HT has been developed and a good agreement between test and modeling results can be observed.
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