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Featured Application: This work can be applied to perishable goods supply chains and emergency logistics. Traditional inventory routing problems ignore the time consumption in transportation. In this paper, an inventory routing problem with air–land transportation and route-dependent lead times is studied. The model is based on the rolling horizon framework which can serve as a "here-and-now" approximation for multi-period inventory routing problems. A planning horizon crossing strategy is proposed to consider the effect of the single-period decision on long-term planning. The box uncertainty set is used to depict demands. A tractable closed-form robust solution for optimal replenishment quantity is derived. An adaptive variable neighborhood search algorithm is developed for this problem. A novel shaking phase is proposed, and the performance of shaking operators is evaluated in numerical experiments. Results also validate the effectiveness of the robust solution and the planning horizon crossing strategy. [ABSTRACT FROM AUTHOR]

The drying process is a significant step in catalyst layer (CL) fabrication, and an in-depth understanding is essential to achieve optimal CL structure and cell performance. This study investigates the impact of the solvent evaporation process on CL structure formation as solvent evaporation dominates the CL structure evolution. To decouple the water-alcohol solvent evaporation behavior during slurry drying, a simultaneous mass-loss and heat-flux measurement method is proposed to determine the evaporation rates of components with different vaporization latent heat. The component mass variation and composition evolution are obtained and utilized for drying kinetics and solvent evaporation law analysis. Results indicate that the ethanol evaporates priority over the water, causing the enrichment of the water phase in the coating at the late drying stages, especially at high drying temperatures. The drying temperature is essential for regulating the drying path, which is directly related to the drying rate and affects the CL structure and performance. The CL structural characterizations reveal that low-temperature drying helps form the homogeneous and crack-free CL, while high-temperature drying promotes porosity and large pore proportion. The proposed novel in-situ monitoring method provides an effective approach for revealing the CL drying process. [Display omitted] • A novel in-situ monitoring method is developed to decouple solvents evaporation behavior. • Insights into drying kinetics and compositional evolution of catalyst layer coatings are provided. • The drying path is proved affecting the catalyst layer structure formation. • The impact of drying temperature on CL physical and electrochemical properties is revealed. • Water-phase solvent enrichment is detrimental to catalyst layer formation. [ABSTRACT FROM AUTHOR]

In order to improve the proppant displacement in the fracture and enhance the fracturing stimulation effect, the experiment on proppant carrying capacity of fracturing fluid was conducted with experimental simulation method and visual-panel fracture device, the formation of in-fracture sand bank was characterized in combination with the microscopic movement trajectory of the proppant particles and the macroscopic shape of sand bank, the difference in sand carrying modes was analyzed between of viscous and non - viscous fracturing fluids, and the effects on the displacement pattern of sand dike was studies in terms of fracture inter-perforation disturbance, fracturing fluid displacement, fracturing fluid viscosity and construction sand ratio. The results indicated that the prop-pant in fractures migrated under the joint action of fluidization and sedimentation, mainly dragged and transported under the action of fluidization; an immobile thin layer of fluid was formed between the fluidized layer and sand bank in viscous fracturing fluid to support the particles, reducing the friction and collision between the fluid and the particles; the formation of the sand bank includes four stages, that is, sand bank formation, development, balancing and piston-like forwarding, the formed sand bank could be characterized by accumulating angle, balancing height and advancing angle under the joint effect of perforation disturbance and fluid erosion, and there were no sand zones in the fractures near the wellbore and in the direction of fracture height; the balancing height of the sand bank mainly depended on the movement speed of proppant particles, inversely proportional to the construction displacement and the fracturing fluid viscosity and directly proportional to the sand ratio. This study provides a reference for the optimization of fracturing operation parameters. [ABSTRACT FROM AUTHOR]

Fluorescence imaging is very useful for skin cancer lesions detection because of its properties of noninvasion and fast imaging. However, conventional fluorescence imaging devices' excitation light source and camera are usually separated, which will cause problems such as complicated structure, large volume, and poor illumination homogeneity. In this paper, we introduce a miniature portable fluorescence imaging device to diagnose skin cancer. A coaxial design has been introduced to combine the exciting light source and fluorescence receiver as an integral part, which significantly reduces the size of the device and ensures illumination homogeneity. The volume of the device is less than 3. 5 × 3. 5 × 9. 5 cm3 with weight of 150 g, and the total power (including the excitation lamp) is only 1.5 W. It is used to detect the squamous cell carcinoma mice for demonstration. The results show that the location of the cancer lesions can be easily distinguished from the images captured by the device. It can be efficiently used to detect early skin tumors with noninvasion. It also has prospects to be integrated with other diagnostic methods such as ultrasound probe, for multiple diagnose of skin tumors thanks to its miniature size. [ABSTRACT FROM AUTHOR]

The fiction and wear and longlife lubrication performances of space lubricants in space environments were investigated. The hydrocarbon lubricant RP4752 was used as the research object, and the vacuum spiral orbit tribometer (SOT) and siding friction test system were used to test the lubricating oils. Nominal lubrication life, wear spot diameter and siding friction coefficient were combined with scanning electron microscopy and X-ray energy dispersive spectrometer for microscopic analysis. The results show that RP4752 has a small siding fiction factor and a long wear life in a vacuum environments, and has good vacuum boundary lubrication performance. The lubricating infrared transmittance has no significant change in 14~16.25µm band. In the vacuum life verification tests, the numbers of rotations of two scanning motors lubricated with RP4752 reach 3.02 X 108, which meets the 8-year on-orbit operating life requirements of the moving mechanisms. The results form a compassion relationship with a nominal life of 1 615 rotations by SOT tests, which provides a test basis for the selection of lubricants for other space motion mechanisms and longlife lubrication design. [ABSTRACT FROM AUTHOR]