•The discharge pattern with distributed flue gas vents is proposed.•The effect of discharge site and direction on the efficiency of tower is discussed.•The influence of the flue gas flow rate on the ...NDWCT performance is studied.•The optimal vents quantity and discharge direction are given.•The optimization model that can be generalize the result to other NDWCTs is proposed.
This paper introduces a distributed arrangement of flue gas emissions and presents conclusions on the optimal placement and quantity of flue gas vents in a certain horizontal plane of a natural draft wet cooling tower (NDWCT). An NDWCT set up based on the arrangement of flue gas vents established herein will raise efficiency with the increase of radial distance and flue gas vents. The authors found a way to inject flue gas at a certain angle, which can make the flue gas and humid air in the tower swirl upward, thereby increasing the pumping force of the cooling tower and further improving the cooling tower efficiency. When the incident angle is parallel to the generatrix of the hyperboloid cooling tower, the cooling tower efficiency is maximized. The flue gas flowrate effect on the cold-water temperature was also investigated based on determining the optimal value of the radial distance, quantity, and angle of the flue gas vent reach. Moreover, the formula that can be generalize the result to other NDWCTs is obtained to reach the optimal emission mode of flue gas. Comparing with the case before improved, the flow rate of NDWCT increases by 822.05 kg/s (18.9%), and the cold-water temperature decreases by 1.12 k, under a 200% flue gas flowrate.
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•The post-harvest ripening affected the drying behavior.•The changes of cell wall components affected the release of flavor substances.•Depolymerization of pectin lead to changes in ...the nanostructure of the cell wall and cellulose network.•The pectin molecular weight of peach and antioxidant activity were used to explore the quality change.•TD- NMR revealed the mechanism of water migration in peaches during post-harvest ripening.
Effect of post-harvest ripening on cell wall polysaccharides nanostructures, water status, physiochemical properties of peaches and drying behavior under hot air-infrared drying was evaluated. Results showed that the content of water soluble pectins (WSP) increased by 94 %, while the contents of chelate-soluble pectins (CSP), Na2CO3-soluble pectins (NSP) and hemicelluloses (HE) decreased during post-harvest ripening by 60 %, 43 %, and 61 %, respectively. The drying time increased from 3.5 to 5.5 h when the post-harvest time increased from 0 to 6 days. Atomic force microscope analysis showed that depolymerization of hemicelluloses and pectin occurred during post-harvest ripening. Time Domain -NMR observations indicated that reorganization of cell wall polysaccharides nanostructure changed water spatial distribution and cell internal structure, facilitated moisture migration, and affected antioxidant capacity of peaches during drying. This leads to the redistribution of flavor substances (heptanal, n-nonanal dimer and n-nonanal monomer). The current work elucidates the effect of post-harvest ripening on the physiochemical properties and drying behavior of peaches.
•Three-area water distribution structure of the cooling tower is proposed.•The effect of spray rate vary with location on the outlet temperature is discussed.•A basic experiment is carried out in the ...field test.•The spray rate with the maximum decrease of the outlet water temperature is given.
A coal-burning power plant’s cooling tower can take away about 55% of the heat that the steam absorbs in the boiler, which represents a big energy saving potential. This paper presents a three-dimensional numerical model to analyze the influence of non-uniform water distribution on the cooling performance of a counter-flow wet cooling tower with different spray rates, while providing thermal calculation of a large cooling tower. In addition, the user-defined function in the fill zone is compiled. The heat and mass transfer in the fill zone is solved by UDF. This study covers a three-area water distribution structure in the water distribution system. Cooling tower data verified the accuracy of the model. The influence of the inner, middle and outer areas in relation to their location on the cooling tower and effect on spray rate on the outlet water temperature was investigated in detail. The effect of the three-area water distribution structure on the velocity field, temperature field and the mass fraction of H2O in the tower are analyzed. The water flow rate that makes the temperature drop to its maximum low point has been given. The results show that the outlet water temperature of the tower can be effectively reduced by adopting the three-area water distribution structure and proper water distribution flow. Consequently, it can improve the efficiency of the cooling tower and generate enormous economic benefits.
Failure mode and effects analysis (FMEA) is a widely used, powerful tool to identify and assess potential failure modes in products and to make products more reliable. Due to the complexity of ...products and lack of knowledge, FMEA involves many uncertainties in practice. In previous studies, numerous modified FMEA methods based on fuzzy logic and Dempster-Shafer (D-S) evidence theory have been employed to address these uncertainties. These studies focus on how to handle uncertainties and to identify a more reliable prioritization of risk priority numbers (RPNs). However, studies have not sufficiently examined how many uncertainties are present in resulting RPNs. To better model and process various types of uncertainties in FMEA, two new area-based metrics are constructed in this paper. One is the interval area metric (IAM), which is used in RPN representation. The other is the dimensionless uncertainty metric (DUM), which is used to measure how many uncertainties there are in RPN. IAM is used to rank the risks in failure modes, and DUM is used to rank the uncertainties in failure modes. Then, an expert system is presented to qualitatively evaluate the DUM, which can help FMEA users intuitively judge whether further investigation should be performed to alleviate the epistemic uncertainties in each failure mode. Finally, a practical risk evaluation case regarding the grinding wheel system of a numerically controlled (NC) machine is provided to demonstrate the application and effectiveness of the proposed FMEA. The case study shows that the calculation programs of IAM and DUM do not require any assumptions or need to address conflict among experts. In addition, proposed method can not only give a more accurate rating of each failure mode, but also help designers intuitively see the uncertainty grade of each RPN, which is useful to help them understand FMEA results.
Molecular tools for double or multimeric G-quadruplexes have recently received high attention due to the possibility to increase detection sensitivity, thermal stabilization and cell imaging ...opportunities, in oder to determine roles and functions of G-quadruplex aggregation in medical context. In this study, two smart berberine-bisquinolinium conjugates (Ber-360A and Ber-PDS), obtained by linking the berberine fluorophore to established G-quadruplex binders (with bisquinolinium scaffold), have been synthesized and evaluated for their G-quadrulex affinity, as well as to establish mechanisms of aggregation. The conjugates are two highly selective, sensitive and fluorescent sensors able to distinguish human telomere double G-quadruplexes from other type of G-quadruplexes and ds DNA. These ligands are the first example of fluorescent tools that bind to two adjacent G-quadruplex units and optically recognize double structures. Furthermore, microscopy experiments demonstrate that the conjugate Ber-PDS enters the nucleoli and targets G-quadruplex DNA in these organelles, by simultaneously displaying a strong telomerase inhibition and antitumor activity.
Two smart berberine-bisquinolinium conjugates are highly selective, sensitive and fluorescent sensors which can distinguish human telomere double G-quadruplexes from other type of G-quadruplexes and ds DNA. Conjugate Ber-PDS accumulates into the nucleoli and targets G-quadruplex DNA, by display also strong telomerase inhibition and antitumor activity. Display omitted
•Two highly selective optical probes for double G-quadruplexes (G2T1) were developed.•The probes specifically target two adjacent G-quadruplex units in one G2T1.•Probe Ber-PDS allows efficient G-quadruplexes visualization by cellular microscopy experiments.•The two probes display strong telomerase inhibition and anticancer activities.
Vacuum-steam pulsed blanching (VSPB) is an emerging blanching method resulting in high efficiency and product quality. However, inconvenient loading, small loading capacity, uneven rinsing and ...imprecise control hinder its application in food industry. Therefore, the current work aimed to design a VSPB machine, including selection of components, building a control system and designing a steam nozzle in order to increase the load capacity and improve device control. For this purpose, a horizontal blanching chamber with internal nozzle was designed and optimized using CFD method. The vacuum chamber design required a more evenly distributed steam inlet. A water-sealing vacuum pump, a cooling device and a hardware system were developed. The distribution of steam released from the nozzle in the chamber was numerically investigated by solving the three-dimensional Reynolds-averaged Navier-Stokes equations, with a velocity uniformity index value of 0.448. The validation blanching test was conducted using garlic scape as the test material. The steam holding time and the number of cycles significantly affected (p < 0.05) the color of the garlic scapes. Peroxidase (POD) activity decreased with the increase of blanching cycles until the enzymes were completely inactivated. VSPB significantly decreased (p < 0.05) the lignin content of the garlic scapes. The findings indicate that the best results were obtained after 2 cycles of VSPB and steam holding time of 30 s.
Hot water and steam thermal blanching are the two most frequently used blanching methods in food processing. Generally, they are used as a pretreatment before drying, freezing or canning of different fruits and vegetables. In current work, an improved vacuum-steam pulsed blanching machine was designed and the validation blanching test with garlic scape as the material indicated that VSPB operation was effective in preventing the synthesis of lignification in garlic scapes. By considering enzyme inactivation, lignification, color, and other quality attributes, 2 cycles of VSPB and steam holding for 30 s were proposed as the optimal VSPB conditions.
•A new type of blanching machine, the horizontal vacuum-steam pulsed blanching machine was developed.•The core components vacuum pump and nozzle are selected and designed respectively.•The control system of the horizontal vacuum-steam pulsed blanching machine is designed and its function realized.•Suitable operating parameters for the blanching machine were obtained through the blanching experiment of garlic scape.
As Lithium-ion batteries become the main power source in various electronics, it is important to predict the remaining useful life (RUL) of these batteries, in order to make the maintenance strategy ...and avoid serious consequences caused by the failure of power supply. With the convenience in fitting field measurements, the model based methods are widely used in RUL prediction for lithium-ion batteries. However, these predictions are usually unreliable because of incomplete uncertainty quantification. This paper proposes a model update method for the RUL prediction of lithium-ion battery based on the Bayesian simulator assessment theory. With an empirical degradation model, the method quantifies the uncertainties in model parameters, model form and measurements error. It infers the reality prediction to battery failure threshold with a combination of multiple uncertainties. The main innovation of the proposed method is that it doesn't only adjust the model parameters, but also the bias function which accounts for the model form uncertainty. And a modular Markov chain Monte Carlo method is employed to implement the model update with multiple uncertain parameters. As uncertainties are considered systematically in the inference process, it can provide a reliable RUL prediction. We demonstrate the predictive capability of the method by the real life cycle dataset of lithium-ion batteries from NASA.
In order to explore an alternative drying method to enhance the drying process and quality of persimmon slices, pulsed vacuum drying (PVD) was employed and the effects of different drying ...temperatures (60, 65, 70, and 75 °C) on drying kinetics, color, rehydration ratio (RR), microstructure, bioactive compounds, and the antioxidant capacity of sliced persimmons were investigated in the current work. Results showed that the rehydration ratio (RR) of the samples under PVD was significantly higher than that of the traditional hot air-dried ones. Compared to the fresh samples, the dried persimmon slices indicated a decrease in the bioactive compounds and antioxidant capacity. The total phenolic content (TPC) of PVD samples at 70 °C was 87.96% higher than that of the hot air-dried persimmon slices at 65 °C. Interestingly, at 70 °C, the soluble tannin content and TPC of the PVD samples reached the maximum values of 6.09 and 6.97 mg GAE/g, respectively. The findings in the current work indicate that PVD is a promising drying method for persimmon slices as it not only enhances the drying process but also the quality attributes.
The aim of this study was to prepare a liposomal delivery system for rapamycin and study its in vitro release characteristics. The results may provide a foundation for the further development of a ...liposomal delivery system for rapamycin and the establishment of a new active treatment method targeted towards the cellular components of atherosclerotic plaques. The ethanol injection method was used to prepare rapamycin-containing liposomes. The formulation was optimized by orthogonal design, and the degree of rapamycin release by the liposomes was measured by the reverse dialysis method. Orthogonal testing showed that the optimum formulation had a phospholipid concentration of 4%, a phospholipid-cholesterol mass ratio of 8:1, a drug-lipid mass ratio of 1:20 and an aqueous phase pH of 7.4. Rapamycin-containing liposomes with an encapsulation efficiency of 82.11±2.13% were prepared, and the in vitro release of rapamycin from the liposomes complied with a first-order kinetic equation. In conclusion, the formulation was optimized, the prepared liposomes had a high rapamycin encapsulation rate and good reproducibility, and their in vitro release had a certain delayed-release effect.
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