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As promising building blocks for molecular electronics, organic molecules have attracted intense research interest. Metal-molecule-metal junctions are often used as testbeds for studying organic molecules' charge transport properties. In this article, fabrication methods, nanoscalability and addressability of these junctions are reviewed. Fabrication approaches are classified into soft contact, scanning probe microscopy, against-nanowire, crossed-wire, shadow angle evaporation and nanopore junctions. The effects of preparation method on the junction charge transport properties are systematically discussed. In general, the scanning tunneling microscopy technique is suitable for fast screening of molecular conductance, but cannot address junction that limits their in-situ temperature-dependent characterizations. The nanopore junction guarantees good control over the device size and the intrinsic contact stability, however, the nature of the electrode-molecule interface is not well understood. Shadow angle evaporation and soft contact techniques can effectively reduce the possibility of device short circuiting; however, the electrode dimensions limit potential applications. The against-nanowire method provides an easy way to fabricate addressable junctions, and if combined with the crossed-wire procedure may have potential for fabrication and three-dimensional integration of molecular junctions.

Due to the serious distribution loss of fresh agriculture products, it attracts more and more attention that how to determine the optimal inventory control strategy, which is one of the research hotspots and difficulties. This study is concerned with an improved Economic Order Quantity (EOQ) model considering fresh-degree sensitive demand and carbon emission, which is proposed to determine the optimum replenishment cycle time and order quantity. In addition, a simulation experiment and sensitivity analysis of parameters (such as carbon emission price, deterioration rate and fresh-degree) are to illustrate the proposed inventory control model, which can provide decision support for the balance of carbon emission cost and inventory cost by adjusting the inventory control strategy. Simulation results show that carbon emission price, deterioration rate and fresh-degree affect the optimal replenishment cycle time and order quantity to some extent. Moreover, suitable carbon emission price can guide fresh retailers to make low-carbon decision through balancing operation cost, carbon emission, deterioration cost and fresh loss cost.