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The efficiency and working performance of the motor and controller system in micro-electric vehicles depends mainly on its thermal performance, which is contingent upon effective and active cooling. The working temperature of the motor and controller may be too high during operation, which properly causes motor power reduction or motor breakdowns. Therefore, it is crucial to design a good cooling channel for better cooling the integrated motor and controller system. This work proposes an integrated cooling channel of motor and controller, and the fluid-solid coupling analysis is applied for analyzing the velocity, pressure distributions of the cooling channel, and temperature distributions of motor solid components. Meanwhile, the collaborative optimization method based on the multi-island genetic algorithm (MIGA) is used to attain optimal design parameters of the integrated cooling channel of the motor and controller for obtaining a better cooling channel design with lower flow resistance and lower winding temperatures. Results show that the original cooling channel's flow resistance and maximum winding temperature are 31.87 kPa and 120.04°C, respectively. The flow resistance and winding temperature are pretty significant. After optimization, the local vortex flow and zero velocity area in optimal cooling channel design are improved, the coolant flow velocity becomes more uniform, and the flow resistance is significantly reduced. The flow resistance and maximum winding temperature of the optimal cooling channel design are 12.5 kPa and 116.76°C, respectively, which are decreased compared with the original cooling channel structure, with a decrease of 39.4% and 2.7%, respectively. The research findings in this work can provide theoretical reference for solid components temperature evaluation of motor and give valuable data to cooling performance evaluation and optimization of integrated cooling channel for motor and controller system. [ABSTRACT FROM AUTHOR]

High-quality baijiu yeast – modified Sporidiobolus johnsonii A (MSJA) suffers from the problem of weak vitality, thus failing to combine high efficiency and high survival rate drying. Therefore, in this study, we firstly designed a real-time sampling experiment of MSJA spray drying process, and based on this, we established a New CFD model (N-CFD model) that can accurately simulate the variation of the spray drying process of microorganisms such as MSJA. Then, a new spray drying air inlet mechanism of "high-temperature cyclone in the center L-type guide plate + medium-temperature laminar flow in the peripheral holes and slots" was invented. Finally, the parametric scanning simulation was carried out to optimize the flow angle θ of the L-type guide plate using the N-CFD model. The results show that, firstly, the N-CFD model can accurately simulate the temperature distribution (P1 = 0.05) and the motion of drying particles in the drying tower. Secondly, the optimized new air inlet mechanism with the L-type guide plate flow angle θ = 47° can even out the temperature and particle distribution in the drying tower, which meets the "two-stage theory of spray drying." Finally, under the premise of ensuring the drying efficiency, the survival rate of MSJA spray drying was increased from 42.6% to 82.24%, which achieved the objectives of low sticking wall, high efficiency and high survival rate of spray drying MSJA. [ABSTRACT FROM AUTHOR]

In order to obtain the optimal technological parameters of lettuce vacuum osmotic dehydration, the effects of osmotic temperature, slice thickness, sucrose concentration, and vacuum degree on the vacuum osmotic dehydration were explored. The lettuce water loss rate and solid gain rate decreased with the increase of slice thickness and vacuum degree, and increased with the increase of sucrose concentration and osmotic temperature. Response surface methodology was applied to analyze the influence of the four influential factors on the evaluated parameters and the optimization of lettuce vacuum osmotic dehydration was studied. The results indicated that, within the experimental scope, the optimized technological parameters of lettuce vacuum osmotic dehydration are the temperature of 28°C, the slice thickness of 2 mm, sucrose concentration of 47%, the vacuum degree of 22 kPa, and the water loss rate and solid gain rate are 72.16% and 11.82%, respectively.

Carbon monoxide (CO) is a vital endogenous gaseous transmitter molecule involved in the regulation of various physiological and pathological processes in living biosystems. In order to investigate the biological function of CO, many technologies have been developed to monitor the level of endogenous CO in biosystems. Among them, the fluorescence detection technology based on the fluorescent probe has the advantages of high sensitivity, excellent selectivity, simple operation, especially non-invasive damage to biological samples, and the possibility of real-time in situ detection, etc., which is considered to be one of the most effective and applicable detection techniques. Therefore, in the last few years, a lot of work has been carried out on the design, synthesis and in vivo fluorescence imaging studies of CO fluorescent probes. Furthermore, using fluorescent probes to detect the changes in CO concentrations in living cells and tissues as well as in organisms has been one of the hot research topics in recent years. However, it is still a challenge to rationally design CO fluorescent probe with excellent optical performance, structural stability, low background interference, good biocompatibility, and excellent water solubility. Therefore, this review focuses on the research progress of CO fluorescent probes in the detection mechanism and biological applications in recent years. However, this popular and leading topic has rarely been summarized comprehensively to date. Thus, the research progress of CO fluorescent probes in recent years is reviewed in terms of their design concept, detection mechanism, and their biological applications. In addition, the relationship between the structure and performance of the probes was also discussed. More significantly, we hope that more excellent optical properties fluorescent probes for gaseous transmitter molecule CO detection and imaging will overcome the current problems of high biotoxicity and limited water solubility in future. [ABSTRACT FROM AUTHOR]

To evaluate the rationality of the cooling system design for a four cylinder engine, computational fluid dynamics method was used to analyze the engine cooling system from layout design, system flowrate determination, flow field of the cooling system and engine temperature field. The optimization design of adding a throttling notch to the cylinder block water jacket was proposed to solve the problem of significant differences in coolant flow velocity in the cylinder block water jacket. The results show that the coolant flow velocity uniformity in cylinder block water jacket is significantly improved, and the wall temperature of each cylinder liner can be reduced by 1~3 °C. The thermal balance test results at an engine speed of 12 000 r/min show that the maximum difference in cylinder temperature is about 4 °C. The oil temperature is about 129 °C, which is controllable (less than 140 °C), indicating that the cooling system of the four cylinder engine is designed reasonably to ensure uniform cooling of each cylinder and oil cooling. [ABSTRACT FROM AUTHOR]

Achieving an optimal cooling of the generator unit is indispensable for high working performance. In this work, computational fluid dynamics analysis on the flow field of the conventional type and silent type of the S688CCS series generator unit is conducted, and design optimization of the generator unit with poor cooling is studied based on flow field analysis results. Flow field simulation results indicate that the total cooling air quantity of the silent type generator unit is lower than that of the conventional type generator unit, and the cooling air quantity of the radiator is also lower than that of the conventional type generator unit, which is not conductive for the cooling of the silent type generator unit. The flow field optimization is achieved by adopting the single variable control method to improve the structure of the fan cover, silent components for silence, adjacent structure, and air inlet grille. The corresponding structure optimization scheme is put forward. After optimization, the air quantity for the cooling radiator of the silent type generator unit is 44.33% higher than that of its original structure, and the total cooling air quantity is higher than that of the conventional type generator unit. The research results in this work can provide a theoretical basis for the design of the cooling air flow path of generator units for achieving an optimal cooling performance. [ABSTRACT FROM AUTHOR]

In current research, the hydraulic performance prediction and optimization of an engine cooling water pump was conducted by computational fluid dynamic (CFD) analysis. Through CFD simulation, the pump head, shaft power and efficiency for the original pump at volume flow rate 25 L/min and impeller rotating speed 4231 r/min were 3.87 m, 66.7 W and 23.09% respectively. For improving hydraulic performance, an optimization study was carried out. After optimization, four potential optimized designs were put forward. The efficiency of the optimized design No.1 for engine cooling water pump was nearly 6% higher than that of the original pump model; and the head of the optimized design No.2 for engine cooling water pump was 9% higher than that of the original pump model. Under the condition of maintaining the pump head and considering comprehensive improvement effect, the optimized design No.3 was considered as the best design and selected as the test case for validating the optimum design. The hydraulic performance predictions for this optimum engine cooling water pump agreed well with experimental data at design condition with relative discrepancies of 2.9% and 5.5% for the pump head and pump efficiency, respectively. It proved that performance prediction calculation model and the automatic optimization model were effective. This research work can provide theoretical basis for the design, development and optimization of engine cooling water pump. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) is one of the important gaseous signalling molecules, which plays key roles in various critical biological processes. In this work, we report a novel two-photon near-infrared (TP-NIR) fluorescent probe (MNIR-H2S) for the sensing of mitochondrial H2S in living cells, tissues, zebrafish and nude mice. Using a xanthene dye as a TP-excitation (810 nm) NIR-emission (668 nm) fluorophore, a well-known H2S response moiety with a robust intramolecular charger transfer (ICT) effect can quickly respond to H2S and effectively quench the fluorescence intensity, and an oxonium cation structure serves as a mitochondria-targeting site. Notably, MNIR-H2S displays high sensitivity, high selectivity, low cytotoxicity, powerful mitochondrial localization ability, deep tissue penetration, and a very minimal imaging background. Biological imaging results show the biological application of MNIR-H2S as a robust new tool for use in H2S imaging in biological systems. [ABSTRACT FROM AUTHOR]

Theoretical analysis and performance evaluation is of great significance to give guidance for engineers designing a better muffler cover of general purpose engine with higher success rate and less experiment trails. Therefore, in order to construct a accurate numerical prediction of muffler temperature analysis accounting for the effects of boundary conditions on temperature results calculation, CFD technology was adopted and the muffler cover of general purpose engines at three different starter states were chosen to carry out this research. Simulation results showed that the simulation results of muffler cover temperature increased with the increase of radiation emissivity and thermal status, and became more consistent with experimental values with the increase of prism layers. The temperature distributions and boundary radiosity distributions of muffler cover for different starter were basically the same. Average temperature of muffler cover was between 60 and70°C under three kinds of starter conditions, and the temperature distribution was reasonable, proving that the design of muffler cover was feasible.The temperature numerical results were basically consistent with the experimental results, and the relative error was within 10%, which indicated that prediction value can be reliable when all boundary conditions were set reasonably and physical-mathematical models was solved with right calculation methods. The research results in this paper can provide a theoretical basis for the early-design and developing of muffler cover for general purpose engine. [ABSTRACT FROM AUTHOR]

In order to meet the needs of customers and take advantage of the customer's innovative resources, companies open up their design activities of products to customers. In contrast to the traditional product innovation, the primary characteristic of open innovation is the participation of a large number of autonomous individuals across organisational boundaries, and there is not a central authority. Hence, it is necessary to study the dynamic mechanism for obtaining a good decision. This paper first studies the evolution of individual interaction based on game theory and then studies the dynamic characteristics of large-scale interaction. According to the results of simulation, it is concluded that the opinions are convergent under various communication conditions, and he convergent velocity distribution of the product solution with payoffs as the independent variable is obtained. A case study is used to deeply understand the participant behaviour based on the game theory and verify the conclusion of dynamic analysis in this paper. [ABSTRACT FROM AUTHOR]

In order to obtain the optimized technological parameters of hot air-vacuum combined drying of lettuce, the effects of hot air temperature, intermediate conversion moisture content, slice thickness and vacuum degree (four influence factors) on lettuce drying were explored. The drying time and rehydration ratio of lettuce were the experimental indices, and the relationships between the experimental indices and the influence factors were analyzed by using the response surface methodology. The regression mathematical models were established. The optimized technological parameters of hot air and vacuum combined drying are 50C hot air temperature, 40% intermediate conversion moisture content (w.b.), 20 kPa vacuum degree and 5 mm slice thickness. Practical Applications Combined drying is widely used in food, which is considered as an effective method to achieve energy conservation and shelf life. The objective of this paper was using response surface methodology to obtain optimized hot air vacuum drying parameters for lettuce. The significance of this research can improve the drying efficiency, provide a reference for other fruits and vegetables' drying process optimization and provide a technical basis for the drying of lettuce and the designing of related equipment. [ABSTRACT FROM AUTHOR]

Aiming at the problem of multilayer physical structure for the skeleton of porous media, a multiscale and multilayer structural model of heat and mass transfer processes for drying of grain packing porous media was established by applying the pore network method and multiscale theory. An experimental study on rice drying was conducted in order to validate this model. The simulation and experimental results indicated that the established model could explain the mechanical properties of rice drying well. The rate of heat transfer was faster than the rate of mass transfer and there was a higher moisture gradient inside the rice grain. The diffusion coefficient of rice embryo played an important role in the drying process, and whose effect on drying was larger than the diffusion coefficient of rice hull and chaff. The moisture was imprisoned effectively inside the rice when the diffusion coefficient of rice embryo was very small. [ABSTRACT FROM AUTHOR]

Cyclone separator, used as the biogas pretreatment equipment, was taken as the research object in this study. In order to improve the separation rate of biogas impurity particles, the influence of six different structural parameters of the cyclone separator on the particle separation rate was analyzed by a single factor control method. It was found that the gas inlet rectangular section size had significant influence on the particle separation rate, followed by the diameter of the gas outlet duct. However, the height of the cylinder and cone, the insertion depth of gas outlet duct, and the diameter of the down-comer tube had limited effects on the particle separation rate. The best improvement scheme was that the diameter of the gas outlet duct was 138 mm, and the gas inlet rectangular section was 130 × 56 mm2. The particle separation rate of 10 μm and above was greater than 98%, and the pressure drop at this time was 2.213 kPa. [ABSTRACT FROM AUTHOR]

Liver injury poses a serious threat to human health and growing evidence suggests that it is closely associated with a biomarker (peroxynitrite, ONOO - ). Therefore, considering that the relationship of ONOO - levels with the occurrence and development of liver injury disease remains a challenge, an urgent need exists to develop a reliable and robust tool for its visual rapid diagnosis and assessment. Herein, a two-photon near-infrared (TP-NIR) ratiometric fluorescent nanoprobe ( NTC ) based on a fluorescence resonance energy transfer (FRET) strategy was designed, synthesized, and characterized, which had the advantages of good water solubility, low background interference, deep tissue penetration, and high imaging resolution. Specially, NTC was constructed by self-assembly of an alkynyl group of a small-molecule fluorescent probe (NR) via click chemistry grafting onto azide chitosan (natural polymeric nanomaterial). NR contained acceptor 1 (NIR fluorophore) and donor 3 ( D -π- A structure of naphthalimide derivative fluorophore) with outstanding TP properties that could be activated by ONOO - for the ratiometric detection of ONOO - . Furthermore, in the presence of ONOO - , NTC exhibited a short response time (∼10 s) and high selectivity and sensitivity toward ONOO - with an excellent detection limit as low as 15.3 nM over other reactive oxygen/nitrogen species. Notably, NTC has been successfully employed for ONOO - detection and imaging in living HepG2 cells, liver injury mice tissues, and mice models with satisfactory results. Thus, the construction of this NTC nanoprobe can provide a robust molecule tool for enabling early diagnosis and assessment of liver injury in the future.

Bisulfite (HSO 3 - ) is usually widely added to tap water and food because it has antibacterial, bleaching, and antioxidant effects. However, its abnormal addition would cause a series of serious diseases related to it. Therefore, development of an effective method for HSO 3 - detection was of great significance to human health. In this work, a new reaction-based ratiometric fluorescent probe KQ-SO 2 was rationally designed, which could be used for the highly selective detection of HSO3 - in tap water, real food samples, onion tissues, and zebrafish. Specifically, a positively charged benzo[ e ]indolium moiety and a carbazole group through a condensation reaction resulted in KQ-SO 2 , which displayed two well-resolved emission bands separated by 225 nm, fast response (1 min), and high selectivity and sensitivity toward HSO3 - upon undergoing the Michael addition reaction, as well as low cytotoxicity in vitro. In addition, KQ-SO 2 has been successfully applied for the detection of HSO 3 - in tap water, real food samples, onion tissues, and zebrafish with satisfactory results. We predict that KQ-SO 2 could be used as a powerful tool to reveal the relationship between HSO3 - and the human health.