Research Summary
Literature suggests that firms may approximate ambidexterity over time by alternating between periods of exploration and exploitation. We theorize and empirically test performance ...implications of two types of temporal transition between exploration and exploitation and their boundary conditions. We find that a discontinuous jump has a negative effect on firm performance while an incremental transition has a positive effect. We also find that the role of firm resources and particularly that of non‐scale‐free resources is critical in shaping the performance effects of the two types of temporal transition. Our findings indicate that the two types of temporal transition have distinct advantages and disadvantages.
Managerial Summary
Firms need to make use of old ideas and search for new ideas to remain competitive. We argue that firms take different approaches to achieve this goal. We find that firms that alternate between old and new ideas in an incremental and continuous manner perform better than firms that switch abruptly between old and new ideas. We also find that the performance effects of the two approaches are more pronounced for firms with limited resources. This finding warns managers of the danger of an abrupt and discontinuous jump between old and new ideas, especially for firms with limited resources.
Humidity sensors are essential components in wearable electronics for monitoring of environmental condition and physical state. In this work, a unique humidity sensing layer composed of ...nitrogen‐doped reduced graphene oxide (nRGO) fiber on colorless polyimide film is proposed. Ultralong graphene oxide (GO) fibers are synthesized by solution assembly of large GO sheets assisted by lyotropic liquid crystal behavior. Chemical modification by nitrogen‐doping is carried out under thermal annealing in H2(4%)/N2(96%) ambient to obtain highly conductive nRGO fiber. Very small (≈2 nm) Pt nanoparticles are tightly anchored on the surface of the nRGO fiber as water dissociation catalysts by an optical sintering process. As a result, nRGO fiber can effectively detect wide humidity levels in the range of 6.1–66.4% relative humidity (RH). Furthermore, a 1.36‐fold higher sensitivity (4.51%) at 66.4% RH is achieved using a Pt functionalized nRGO fiber (i.e., Pt‐nRGO fiber) compared with the sensitivity (3.53% at 66.4% RH) of pure nRGO fiber. Real‐time and portable humidity sensing characteristics are successfully demonstrated toward exhaled breath using Pt‐nRGO fiber integrated on a portable sensing module. The Pt‐nRGO fiber with high sensitivity and wide range of humidity detection levels offers a new sensing platform for wearable humidity sensors.
Nitrogen‐doped graphene fiber functionalized by Pt nanoparticles (Pt‐nRGO fiber) is integrated on a flexible and transparent polyimide substrate for application in real‐time and on‐site monitoring of humidity. This work demonstrates the humidity sensing characteristic of Pt‐nRGO fiber, which further expands versatility of graphene‐based fiber in wearable sensing electronics.
Achieving an improved understanding of catalyst properties, with ability to predict new catalytic materials, is key to overcoming the inherent limitations of metal oxide based gas sensors associated ...with rather low sensitivity and selectivity, particularly under highly humid conditions. This study introduces newly designed bimetallic nanoparticles (NPs) employing bimetallic Pt‐based NPs (PtM, where M = Pd, Rh, and Ni) via a protein encapsulating route supported on mesoporous WO3 nanofibers. These structures demonstrate unprecedented sensing performance for detecting target biomarkers (even at p.p.b. levels) in highly humid exhaled breath. Sensor arrays are further employed to enable pattern recognition capable of discriminating between simulated biomarkers and controlled breath. The results provide a new class of multicomponent catalytic materials, demonstrating potential for achieving reliable breath analysis sensing.
Effective strategy to readily synthesize highly dispersed Pt‐based bimetallic (PtM, where M = Pd, Rh, and Ni) NPs as a new class of active catalysts is successfully developed on the highly porous architecture of 1D WO3 nanofibers via a protein template, i.e., apoferritin, in combination with the electrospinning method for superior exhaled‐breath sensors.
We report on the heterogeneous sensitization of metal–organic framework (MOF)-driven metal-embedded metal oxide (M@MO) complex catalysts onto semiconductor metal oxide (SMO) nanofibers (NFs) via ...electrospinning for markedly enhanced chemical gas sensing. ZIF-8-derived Pd-loaded ZnO nanocubes (Pd@ZnO) were sensitized on both the interior and the exterior of WO3 NFs, resulting in the formation of multiheterojunction Pd–ZnO and ZnO–WO3 interfaces. The Pd@ZnO loaded WO3 NFs were found to exhibit unparalleled toluene sensitivity (R air /R gas = 4.37 to 100 ppb), fast gas response speed (∼20 s) and superior cross-selectivity against other interfering gases. These results demonstrate that MOF-derived M@MO complex catalysts can be functionalized within an electrospun nanofiber scaffold, thereby creating multiheterojunctions, essential for improving catalytic sensor sensitization.
Research summary: Since Nickerson and Zenger (2002) proposed how vacillation may lead to organizational ambidexterity, large-sample empirical tests of their theory have been missing. In this paper, ...we empirically examine the performance implications of vacillation. Building upon vacillation theory, we predict that the frequency and scale of vacillation will have inverted U-shaped relationships with firm performance. We test our hypotheses using patent-based measures of exploration and exploitation in the context of technological innovation and knowledge search. Managerial summary: Firms often shift their focus on technological innovation and knowledge search from seeking new and novel knowledge (i.e., exploration) to extending and refining existing knowledge (i.e., exploitation) or vice versa. We examine how the frequency and scale of firms vacillating between exploration and exploitation may affect their performance. We find that both too infrequent or too frequent changes and a too small or too large scale of changes are not desirable.
1D metal‐oxide nanotube (NT) structures have attracted considerable attention for applications in chemical sensors due to their high surface area and unique chemical and physical properties. ...Moreover, bimodal pores, i.e., meso‐ and macro‐sized pores, which are formed on the shell of NTs, can further facilitate gas penetration into the sensing layers, leading to much improved sensing properties. However, thin‐walled NTs with bimodal pore distribution have been rarely fabricated due to the limitations of synthetic methods. Here, Ostwald ripening‐driven electrospinning combined with sacrificial templating route using polystyrene (PS) colloid and bioinspired protein is firstly proposed for producing both bi‐modal pores and catalyst‐loaded thin‐walled SnO2 NTs. Homogeneous catalyst loading on porous SnO2 NTs is achieved by the protein cage that contains catalysts and PS colloids and protein shells are thermally decomposed during calcination of electrospun fibers, resulting in the creation of dual‐sized pores on NTs. Pt catalyst decorated porous SnO2 NTs (Pt‐PS_SnO2 NTs) show exceptionally high acetone gas response, superior selectivity against other interfering gases, and very low limit of detection (10 ppb) to simulated diabetic acetone molecules. More importantly, sensor arrays assembled with developed porous SnO2 NTs enable the direct distinction between the simulated diabetic breath and normal breath from healthy people.
Highly mesoporous SnO2 nanotubes (NTs) functionalized with large pores and bioinspired catalysts (Pt‐PS_SnO2 NTs) are simply synthesized as an ideal nanostructure of sensing layers by using biotemplating route and diffusion of SnO2 effect. Pt‐PS_SnO2 NTs exhibit dramatically enhanced acetone sensing performance; especially, they can clearly distinguish the exhaled breath of healthy people and diabetics.
Practical sensing applications such as real‐time safety alerts and clinical diagnoses require sensor devices to differentiate between various target molecules with high sensitivity and selectivity, ...yet conventional devices such as oxide‐based chemo‐resistive sensors and metal‐based surface‐enhanced Raman spectroscopy (SERS) sensors usually do not satisfy such requirements. Here, a label‐free, chemo‐resistive/SERS multimodal sensor based on a systematically assembled 3D cross‐point multifunctional nanoarchitecture (3D‐CMA), which has unusually strong enhancements in both “chemo‐resistive” and “SERS” sensing characteristics is introduced. 3D‐CMA combines several sensing mechanisms and sensing elements via 3D integration of semiconducting SnO2 nanowire frameworks and dual‐functioning Au metallic nanoparticles. It is shown that the multimodal sensor can successfully estimate mixed‐gas compositions selectively and quantitatively at the sub‐100 ppm level, even for mixtures of gaseous aromatic compounds (nitrobenzene and toluene) with very similar molecular structures. This is enabled by combined chemo‐resistive and SERS multimodal sensing providing complementary information.
Synergistic electrical and optical multimodal sensing by 3D nanoarchitectures for label‐free gas detection is reported.
This study examines how family values in a firm can impact non‐market strategies. Given that family members on the board tend to pursue non‐economic, especially family related, values, we attempt to ...specify how the perspectives, values, and tastes of family members serving on the board can be infused into the firm's environmental performance. Since actions addressing environmental issues are less directly related to family values than other types of CSR actions, such as donations and services to the local community, the family‐value‐infused characteristics of boards that represent family firms' pursuit of socio‐emotional wealth, can make firms less committed to environmental issues. Using our comprehensive sample of large U.S. firms consisting of 15,086 firm‐year observations between 1998 and 2016, we find that when family values are treated as a critical factor for non‐market strategies, family dominated firms are less likely to pursue corporate environmental responsibility. We also find that both external and internal factors can positively moderate the family firm's environmental underperformance by diluting the family values.
Optically reduced graphene oxide (ORGO) sheets are successfully integrated on silver nanowire (Ag NW)‐embedded transparent and flexible substrate. As a heating element, Ag NWs are embedded in a ...colorless polyimide (CPI) film by covering Ag NW networks using polyamic acid and subsequent imidization. Graphene oxide dispersed aqueous solution is drop‐coated on the Ag NW‐embedded CPI (Ag NW‐CPI) film and directly irradiated by intense pulsed light to obtain ORGO sheets. The heat generation property of Ag NW‐CPI film is investigated by applying DC voltage, which demonstrates unprecedentedly reliable and stable characteristics even in dynamic bending condition. To demonstrate the potential application in wearable chemical sensors, NO2 sensing characteristic of ORGO is investigated with respect to the different heating temperature (22.7–71.7 °C) of Ag NW‐CPI film. The result reveals that the ORGO sheets exhibit high sensitivity of 2.69% with reversible response/recovery sensing properties and minimal deviation of baseline resistance of around 1% toward NO2 molecules when the temperature of Ag NW‐CPI film is 71.7 °C. This work first demonstrates the improved reversible NO2 sensing properties of ORGO sheets on flexible and transparent Ag NW‐CPI film assisted by Ag NW heating networks.
Optically reduced graphene oxide (ORGO) is achieved on a silver nanowire (Ag NW)‐embedded colorless polyimide (CPI) heater substrate for application in wearable chemical sensors. The ORGO sheets exhibit improved reversible reaction and recovery kinetics by the controlled operating temperatures using Ag NW‐embedded CPI heater.
Conductive porous materials having a high surface reactivity offer great promise for a broad range of applications. However, a general and scalable synthesis of such materials remains challenging. In ...this work, the facile synthesis of catalytic metal nanoparticles (NPs) embedded in 2D metal–organic frameworks (MOFs) is reported as highly active and conductive porous materials. After the assembly of 2D conductive MOFs (C‐MOFs), i.e., Cu3(hexahydroxytriphenylene)2 Cu3(HHTP)2, Pd or Pt NPs are functionalized within the cavities of C‐MOFs by infiltration of metal ions and subsequent reduction. The unique structure of Cu3(HHTP)2 with a cavity size of 2 nm confines the bulk growth of metal NPs, resulting in ultra‐small (≈2 nm) and well‐dispersed metal NPs loaded in 2D C‐MOFs. The Pd or Pt NPs‐loaded Cu3(HHTP)2 exhibits remarkably improved NO2 sensing performance at room temperature due to the high reactivity of catalytic metal NPs and the high porosity of C‐MOFs. The catalytic effect of Pd and Pt NPs on NO2 sensing of Cu3(HHTP)2, in terms of reaction rate kinetics and activation energy, is demonstrated.
Ultra‐small and well‐dispersed metal nanoparticles (NPs) are embedded in the cavities of 2D conductive metal–organic frameworks (C‐MOFs), for the synthesis of highly active and porous conductive materials. The catalytic metal NPs‐loaded C‐MOFs exhibit dramatically improved NO2 sensing performance at room temperature, due to the high reactivity of catalytic metal NPs and the high porosity of the electrically conductive MOFs.
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