Research suggests that the risk and uncertainty associated with entrepreneurial activity deters entry and contributes to the high rates of new business failure. In this study, we examine how the ability to reduce these factors by means of hybrid entrepreneurship-the process of starting a business while retaining a "day job" in an existing organization-influences entrepreneurial entry and survival. Integrating insights from real options theory with logic from the individual differences literature, we hypothesize and find that individuals who are risk averse and have low core self-evaluation are more likely to enter hybrid entrepreneurship relative to full-time self-employment. In turn, we argue and find that hybrid entrepreneurs who subsequently enter full-time self-employment (i.e., quit their day job) have much higher rates of survival relative to individuals who enter full-time self-employment directly from paid employment. Adding support to our theory that the survival advantage is driven by a learning effect that takes place during hybrid entrepreneurship, we find that the decrease in exit hazard is stronger for individuals with prior entrepreneurial experience. Taken together, our findings suggest that individual characteristics may play a greater role in determining the process of how (rather than if) entrepreneurial entry occurs, and that the process of how entrepreneurial entry transpires has important implications for new business survival.

In this paper, we discovered that ZnFe(2)O(4) magnetic nanoparticles (MNPs) possess intrinsic peroxidase-like activity. ZnFe(2)O(4) MNPs exhibit several advantages such as high catalytic efficiency, good stability, monodispersion, and rapid separation over other peroxidase nanomimetics and horseradish peroxidase (HRP). ZnFe(2)O(4) MNPs were used as a colorimetric biosensor for the detection of urine glucose. This method is simple, inexpensive, highly sensitive, and selective for glucose detection using glucose oxidase (GOx) and ZnFe(2)O(4) MNPs with a linear range from 1.25 × 10(-6) to 1.875 × 10(-5) mol L(-1) with a detection limit of 3.0 × 10(-7) mol L(-1). The color change observable by the naked eyes based on the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) is the principle for the sensing of urine glucose level.

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Intriguing ZnO dendritic nanostructures have been synthesized by a two-step chemical vapor deposition process. Regular nanorods grow uniformly to the presynthesized ZnO nanowires on silicon substrate, the secondary nanorods are single-crystal hexagonal ZnO, and each nanorod grows along the [0001] direction. The relationship between the secondary-grown nanorods and the primary ZnO nanowire is not epitaxial due to the high temperature-increasing rate during the rapid grown process. The size and morphology of branches can be controlled by adjusting the temperature and duration of growth. Room temperature photoluminescence (PL) and mircrowave absorption properties of the ZnO dendritic nanostructures have been investigated in detail. The value of minimum reflection loss for the composite with 50 vol % ZnO dendritic nanostructures is -42 dB at 3.6 GHz with a thickness of 5.0 mm. Hierarchical nanostructures of this type are ideal objects for the fabrication of nanoscale functional devices.

Because 2,4,6-trinitrophenol (TNP) and its analogues such as 2,4,6-trinitrotoluene (TNT) possess similar chemical structures and properties, the reliable and accurate detection of TNP from its analogues still remains a challenging task. In the present work, a selective and sensitive method based on the water-soluble silicon nanoparticles (SiNPs) for the determination of TNP was established. The SiNPs with good thermostability and excellent antiphotobleaching capability were prepared via a simple one-pot method. Compared with the synthesized time of other nanomaterials with respect to the detection of TNP, this method avoided a multistep and time-consuming synthesis procedure. Significantly, the fluorescence of the SiNPs could be remarkably quenched by TNP via an inner filter effect. A wide linear range was obtained from 0.02 to 120 μg/mL with a limit of detection of 6.7 ng/mL. The method displayed excellent selectivity toward TNP over other nitroaromatic explosives. The proposed fluorescent method was successfully applied to the analysis of TNP. Moreover, a straightforward and convenient fluorescent filter paper sensor was developed for the detection of TNP, providing a valuable platform for TNP sensing in public safety and security.

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Two-dimensional covalent organic frameworks (2D COFs) are emerging crystalline 2D organic material comprising planar and covalent networks with long-ranging structural order. Benefiting from their intrinsic porosity, crystallinity, and electrical properties, 2D COFs have displayed great potential for separation, energy conversion, and electronic fields. For the most of these applications, large-area and highly-ordered 2D COFs thin films are required. As such, considerable efforts have been devoted to exploring the fabrication of 2D COF thin films with controllable architectures and properties. In this chapter, we aim to provide the recent advances in the fabrication of 2D COF thin films and highlight the advantages and limitations of different methods focusing on chemical bonding, morphology, and crystal structure.

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