The newsvendor problem with an in-season price adjustment

Consider a retailer stocking a seasonal item facing a stochastic demand where information about the demand becomes more accurate as the selling season progresses. The retailer places orders before the start of the season and in-season reorders are not possible. This article extends the classical newsvendor model by allowing the retailer to make an in-season price adjustment after conducting a review and using the realized demand to obtain an accurate estimate of the remaining demand. Our results include answers to the following questions. What price should the retailer choose? How much should the retailer have ordered at the start of the season given the option of adjusting prices in-season? This model was motivated by a problem in car rental revenue management and has applications in perishable assets revenue management (PARM), where price adjustments are needed towards the end of the selling season.     

Dearomatization Approach Toward a Superbenzoquinone‐Based Diradicaloid,Tetraradicaloid, and Hexaradicaloid

Reported here is the step‐by‐step dearomatization of a highly aromatic polycyclic aromatic hydrocarbon (PAH), the hexa‐peri‐hexabenzocoronene (also called as “superbenzene”), to give a series of superbenzoquinones containing two, four, and six ketone groups. Different from traditional PAH‐based quinones, these superbenzoquinones show open‐shell multiradical character by rearomatization in the open‐shell forms as experimentally validated by X‐ray crystallographic analysis, NMR and ESR spectroscopy, and FT‐IR measurements, as well as theoretically supported by restricted active space spin‐flip calculations. These compounds exhibit structure‐ and molecular‐symmetry‐dependent optical, electrochemical, and magnetic properties.     

The Mirror Systems of Integrable Equations

We provide an algorithm to convert integrable equations to regular systems near noncharacteristic, movable singularity manifolds of solutions. We illustrate how the algorithm is equivalent to the Painlevé test. We also use thealgorithm to prove the convergence of the Laurent series obtained from the Painlevé test.     

基于酶催化沉积放大的电化学阻抗法用于人免疫球蛋白M的检测

提出了一种基于酶催化沉积放大的电化学免疫分析方法。先通过免疫夹心反应,将酶标抗体(羊抗人IgM-HRP)固定到电极表面。通过HRP催化双氧水氧化3,3′-二氨基联苯胺在电极表面形成不溶性沉积物,从而放大电化学检测信号。实验通过蛋白A实现抗体的定向固定。考察了包被抗体的浓度和包被溶液的pH对抗体固定的影响,以及酶标抗体的用量和沉积时间对免疫分析的影响。传感器信号响应与人免疫球蛋白M(IgM)浓度在2.1~670μg/L范围内具有良好的线性关系;检出限达0.08μg/L。     

Piezoelectric immunosensor based on magnetic nanoparticles with simple immobilization procedures

A novel method for immobilizing antibodies (antigens) based on magnetic nanoparticles has been proposed for piezoelectric immunoassay. The goat-anti-IgG antibody (IgGAb) as the model analyte was first covalently immobilized to magnetic nanoparticles, which were surface modified with amino-groups. The magnetic bio-nanoparticles (MBN-s) formed were attached to the surfaces of quartz crystal with the help of a permanent magnet. The detection of immunoglobulin G (IgG) was performed with the sensor prepared. The process of immobilization and immunoreaction was monitored by frequency recording. From the SEM images of the sensor surface before and after immobilization of MBN, one can see that the MBN was homogeneously adsorbed on sensor surface. The piezoelectric immunosensor can determine IgG in the range of 0.6-34.9 μg ml⁻¹ with a detection limit of 0.36 μg ml⁻¹. The MBN and immunocomplex layer can easily be removed simply by taking away the magnetic field, making the piezoelectric sensor easy to be regenerated.     

New carbon-rich materials for electronics, lithium battery, and hydrogen storage applications

Methods for the preparation of novel carbon-rich materials for use in electronic devices, lithium batteries or possible hydrogen storage applications are presented.     

Super‐heptazethrene

The challenging synthesis of a laterally extended heptazethrene molecule, the super‐heptazethrene derivative SHZ‐CF3 , is reported. This molecule was prepared using a strategy involving a multiple selective intramolecular Friedel–Crafts alkylation followed by oxidative dehydrogenation. Compound SHZ‐CF3 exhibits an open‐shell singlet diradical ground state with a much larger diradical character compared with the heptazethrene derivatives. An intermediate dibenzo‐terrylene SHZ‐2H was also obtained during the synthesis. This study provides a new synthetic method to access large‐size quinoidal polycyclic hydrocarbons with unique physical properties.     

Uniform local well-posedness for the density-dependent magnetohydrodynamic equations

We prove uniform local-in-time existence and uniqueness of solutions to the density-dependent magnetohydrodynamic equations.